eduagarcia/scielo_abstracts · Datasets at Hugging Face

scl/1516-1439/S1516-14392021000100223.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100223

10.1590/1980-5373-mr-2020-0135

ENGINEERING, CHEMICAL

China Electric Power Research Institute

null

Study of the M-doped Effect (M=Al, Ag, W) on the Dissociation of O2 on Cu Surface Using a First Principles Method

Qiao, Yaxia

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

The O2 adsorption and dissociation on M-doped (M=Al, Ag, W) Cu (111) surface were studied by density functional theory. The adsorption energy of adsorbate, the average binding energy and surface energy of Cu surface, and the doping energy of doping atom were calculated. All the doped atoms can be stably combined with Cu atoms and improve the surface activity of Cu surface, while the Al and W atoms would strengthen the bonding effect between the atoms on the Cu (111) slab except Ag doping atom. Due to the different electronegativity of three metals of Al, Ag, W, these doping atoms can resist the dissociation of O2 by DOS analysis. The potential energy surface was computed, and the result showed that the dissociation reaction of O2 on the surfaces not only reflected in the barrier energy, but also the reaction energy. Ag atoms had the best resistance effect on the O2 dissociation comparing with Al and W atoms because of the large barrier energy and reaction energy.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100223&lng=en&tlng=en

25

scielo_articles/scl/1516-1439/S1516-14392021000100223.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Qiao, Yaxia", "Xu, Lingling", "Zhang, Hao", "Luo, Hongjian" ]

null

[ "O2 adsorption", "Metal doped", "Cu (111)", "Dissociation" ]

null

[ "China Electric Power Research Institute", "Equipment Management Department of State Grid Co.", "State Grid Zhejiang Electric Power Research Institute" ]

scl/1516-1439/S1516-14392021000100221.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100221

10.1590/1980-5373-mr-2020-0383

ENGINEERING, CHEMICAL

Universidade Federal de São Carlos

null

Surfaces, Interfaces and Crystal Growth of Marcasite FeS2

Arrouvel, Corinne

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Marcasite mineral is a metastable iron sulphide, α-FeS2, less known and less abundant than pyrite β-FeS2. Their chemical compositions are similar, formed by S22- dimers and Fe2+ species, but the marcasite crystal structure is orthorhombic while pyrite is cubic. The thermodynamic stability of a range of selected surfaces and their kinetic growth are analysed with molecular mechanics simulations implemented in METADISE code. The most stable surface of marcasite corresponds to the (101) surface having the lowest surface energy (marcasite γ 101 = 1.06 Jm-2) and the most favoured kinetic growth rate is expected for the [010] direction (the attachment energy of (010) surface is 0.20 |eV|/at). Mirror twinning is another characteristic of the mineral contributing to a distinctive crystal growth forming different shapes such as striated needles or pseudo-pentagonal flowers. Similarities, differences and overgrowth between the two dimorphs are highlighted.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100221&lng=en&tlng=en

43

scielo_articles/scl/1516-1439/S1516-14392021000100221.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Arrouvel, Corinne" ]

null

[ "FeS2", "force field", "morphology", "grain boundary", "striations" ]

null

[ "Universidade Federal de São Carlos" ]

scl/1516-1439/S1516-14392021000100214.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100214

10.1590/1980-5373-mr-2020-0403

ENGINEERING, CHEMICAL

Universidade Federal de São Paulo

null

45S5 Bioglass-Derived Glass-Ceramic Scaffolds Containing Niobium Obtained by Gelcasting Method

Siqueira, Lilian de

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Scaffolds of bioglass derived from BG45S5 (45 wt% SiO2, 24.5 wt% CaO, 24.5 wt% Na2O and 6 wt% P2O5) containing 10 wt% niobium were prepared by gelcasting method. The scaffolds presented a 3D porous structure with interconnected and spherical pores (pore size range 100 μm to 500 μm) and high porosity (89%), similar to trabecular architecture of spongy bone. The compressive strength was 0.18 ± 0.03 MPa which is acceptable for bone repair applications. The in vitro biological studies showed cytocompatibility for human osteoblastic cells as well tendency for higher alkaline phosphatase activity. Therefore, the findings here suggest the great potential of the scaffolds for using in bone tissue engineering.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100214&lng=en&tlng=en

21

scielo_articles/scl/1516-1439/S1516-14392021000100214.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Siqueira, Lilian de", "Grenho, Liliana", "Fernandes, Maria H.", "Monteiro, Fernando J.", "Trichês, Eliandra S." ]

null

[ "Bioglass, Niobium oxide, Scaffold", "Gelcasting method, Porous materials, Bone tissue engineering" ]

null

[ "Universidade Federal de São Paulo", "Universidade do Porto", "Universidade do Porto", "Universidade do Porto", "Universidade do Porto", "Universidade do Porto" ]

scl/1516-1439/S1516-14392021000100220.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100220

10.1590/1980-5373-mr-2020-0341

ENGINEERING, CHEMICAL

Jilin Jianzhu University

null

Experimental Study on Mechanics and Pressure Sensitivity of Carbon Fiber RPC

Ge, Lincai

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

To study the mechanical properties and conductivity enhancement effect of carbon fiber (CF) on reactive powder concrete (RPC), this work systematically investigated the changes in the compressive strength, elastic modulus, Poisson’s ratio, and pressure sensitivity of RPC under standard curing system. With age, CF content, and pressure sensitivity as parameters, the micro-method for scanning mechanism was used to study the effect mechanism of CF content on RPC. The experimental results showed that with the increase of carbon fiber content, poisson's ratio and compressive strength of carbon fiber RPC tended to increase first and then decrease. The elastic modulus decreased first and then increased, and 0.75% was the turning point of fiber content. With the increase of carbon fiber content, the resistivity decreases gradually, while the resistivity change rate (FCR) shows a trend of increasing and decreasing first, and there is a strong corresponding relationship between strain and FCR.When the CF content is 0.75%, the maximum FCR is 38.8%, which is increased by 33%. the CF RPC with a CF content of 0.75% is the highest stress and strain sensitivity group, reaching 2.05%/Mpa and 513.7, respectively.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100220&lng=en&tlng=en

29

scielo_articles/scl/1516-1439/S1516-14392021000100220.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Ge, Lincai", "Zhang, Xuejian", "Jin, Xiaofei", "Zhang, Yunlong", "Wang, Jing" ]

null

[ "Reactive powder concrete", "Smart concrete", "Carbon fiber", "Pressure sensitivity", "Mechanical properties" ]

null

[ "Jilin Jianzhu University", "Jilin Jianzhu University", "China Construction First Group Corporation Limited" ]

scl/1516-1439/S1516-14392021000100219.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100219

10.1590/1980-5373-mr-2020-0319

ENGINEERING, CHEMICAL

Pontifícia Universidade Católica do Rio de Janeiro

null

On the Influence of Mean Shear Stress on Multiaxial High Cycle Fatigue of Metallic Materials

Castro, Tiago Lima

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

A study has been made of the influence of a superimposed mean shear stress on the capability of some multiaxial high cycle fatigue criteria to predicting fatigue behavior of 42CrMo4 and 34Cr4 alloy steels. Five selected critical plane-based criteria, namely Matake (M), Susmel & Lazzarin (S&L), Findley (F), Carpinteri & Spagnoli (C&S) and Liu & Mahadevan (L&M), were applied to a number of published experimental fatigue resistance limit tests, involving synchronous sinusoidal in-phase and out-of-phase bending and torsion. Applying to the same loading conditions a mesoscopic scale-based criterion proposed by Papadopoulos (P), one could verify that predictive capability of such an approach is almost invariably superior to those associated with the M, S&L, F, C&S and L&M models. As the Papadopoulos criterion is independent of mean shear stress, it seems appropriate to conclude that the inclusion of such a stress as loading parameter in the critical plane-based models does, in fact, exert a negative influence on their predictive capability. Finally, it is worth mentioning that, except for the Matake, S&L and L&M criteria, the other critical plane-based criteria exhibit a dependence of the fatigue resistance in pure torsion with respect to a superimposed mean shear stress, in disagreement with well-established experimental observations.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100219&lng=en&tlng=en

19

scielo_articles/scl/1516-1439/S1516-14392021000100219.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Castro, Tiago Lima", "Pereira, Marcos Venicius S.", "Darwish, Fathi Aref" ]

null

[ "sinusoidal bending and torsion", "critical plane", "mesoscopic scale" ]

null

[ "Pontifícia Universidade Católica do Rio de Janeiro", "Universidade Federal Fluminense" ]

scl/1516-1439/S1516-14392021000100218.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100218

10.1590/1980-5373-mr-2020-0142

ENGINEERING, CHEMICAL

Universidad Nacional de Colombia

null

The Chalcogenide Compound Fe2SnSe4: Synthesis and Crystal Structure Analysis by Powder X-ray Diffraction

Delgado-Niño, Pilar

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Fe2SnSe4 belongs to the adamantine family of quaternary chalcogenides crystallizing in the olivine type structure, which can be described from a hexagonal close-packing of selenium anions with the octahedral and tetrahedral sites occupied by the iron and tin cations, respectively. The structural characterization of the sample, synthesized by the melt and annealing technique, was carried out by powder X-ray diffraction at room temperature. The XRD data analysis shows, that Fe2SnSe4 adopt the orthorhombic olivine type structure, space group Pnma, and unit cell parameters a = 13.2019(3) Å, b = 7.6746(1) Å, c = 6.3572(1) Å, V = 644.11(2) Å3 were derived.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100218&lng=en&tlng=en

47

scielo_articles/scl/1516-1439/S1516-14392021000100218.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Delgado-Niño, Pilar", "Chacón, Cecilia", "Marroquin, Gustavo", "Delgado, Gerzon E." ]

null

[ "Chacogenides", "Olivines", "Chemical synthesis", "Crystal structure", "Powder X-ray diffraction", "Rietveld refinement" ]

null

[ "Universidad Nacional de Colombia", "Centro de Tecnología para Aguas Profundas", "Instituto Politécnico Nacional", "Universidad de Los Andes" ]

scl/1516-1439/S1516-14392021000100217.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100217

10.1590/1980-5373-mr-2020-0144

ENGINEERING, CHEMICAL

Centro Federal de Educação Tecnológica de Minas Gerais

null

Electrolytic Deposition of Ni/NiO on Stainless Steel for Production of Selective Surfaces

Peixoto, Caio Santiago

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The solar energy is one of the most promising energy sources today. In this context, the goal of this work is to produce selective surfaces for receiver tubes of parabolic trough collectors (PTCs). Ideally, solar collectors should have an absorbing surface that has high absorptance for radiation in the solar energy spectrum and, at the same time, low emittance. Therefore, Ni/NiO selective surfaces were produced with Ni in the first film and NiO in the second film. The method used was by electrolytic deposition of nickel on stainless steel AISI 304, followed by oxidation in a muffle furnace. The thicknesses of the coatings were measured with the photometer Digimess, making it possible to verify their variations and the surface irregularities typical of the electrodeposition procedure. The NiO film was observed in scanning electron microscope (SEM). The film hardness was evaluated by the pencil hardness test and the adhesion by the tape test.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100217&lng=en&tlng=en

23

scielo_articles/scl/1516-1439/S1516-14392021000100217.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Peixoto, Caio Santiago", "Teles Neto, Milton", "Shigaki, Yukio", "Silva, Nilo Nogueira da", "Sade, Wagner" ]

null

[ "Selective Surfaces", "Concentrating Collectors", "Energy", "Electrolytic Deposition" ]

null

[ "Centro Federal de Educação Tecnológica de Minas Gerais", "Universidade de São Paulo" ]

scl/1516-1439/S1516-14392021000100216.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100216

10.1590/1980-5373-mr-2020-0276

ENGINEERING, CHEMICAL

Universidade de São Paulo

null

Analysis of Processing Parameters to Avoid Additional Oxygen Contamination During Production of Zr-based Bulk Metallic Glasses by Suction Casting in an Arc-melting Furnace

Campos Neto, Nelson Delfino de

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

This study first reports details of a successful arc-melting furnace in the production of bulk metallic glasses (BMGs). Also, the study presents the results of a statistical experiment evaluating critical processing parameters that can increase oxygen concentration and its effects on the glass forming ability (GFA) of two Zr-based BMGs. The experiments on Zr48Cu46.5Al4Nb1.5 BMG composite found that using low arc-current (200 A), short melting time (11 s), positive pressure of argon inert gas trapped in the synthesis chamber, and the absence of prior melting of a Ti-getter results in a lower oxygen contamination in the produced alloy. The second experiment using the Vitreloy 105 BMG alloy proved the previous findings.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100216&lng=en&tlng=en

16

scielo_articles/scl/1516-1439/S1516-14392021000100216.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Campos Neto, Nelson Delfino de", "Pereira, Flavio Soares", "Oliveira, Marcelo Falcão de" ]

null

[ "Bulk metallic glasses, Glass forming ability, Arc-melting", "Suction casting, Ti-getter" ]

null

[ "Universidade de São Paulo", "Colorado School of Mines" ]

scl/1516-1439/S1516-14392021000100215.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100215

10.1590/1980-5373-mr-2020-0408

ENGINEERING, CHEMICAL

Universidade Federal de Itajubá

null

Comparative Study Between Sensitization Degree of the 0.4% Mo Austenitic Stainless Steel and UNS S31803 Duplex Stainless Steel

Lacerda, José C. de

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

This study aims at assessing the degree of susceptibility to intergranular corrosion of the UNS S31803 duplex stainless steel and the 0.4% Mo austenitic stainless steel through the double-loop electrochemical potentiodynamic reactivation (DL-EPR) test. Both steels were subjected to isothermal treatments at 650ºC and 900ºC in order to compare the effect of temperature on the respective degrees of sensitization. It was observed that the 0.4% Mo austenitic stainless steel presented a higher degree of sensitization and, consequently, a greater susceptibility to the intergranular corrosion process when compared to the UNS S31803 duplex stainless steel in the two temperatures studied. It was also observed that, for both steels, the heat treatment at 900ºC resulted in a higher degree of sensitization when compared to the heat treatment at 650ºC.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100215&lng=en&tlng=en

20

scielo_articles/scl/1516-1439/S1516-14392021000100215.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Lacerda, José C. de", "Freitas, Lucas L. de", "Brito, Rogério F.", "Moura Filho, Francisco", "Teixeira, Ricardo L.P." ]

null

[ "intergranular corrosion", "degree of sensitization", "DL-EPR" ]

null

[ "Universidade Federal de Itajubá" ]

scl/1516-1439/S1516-14392021000800214.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000800214

10.1590/1980-5373-mr-2021-0328

ENGINEERING, CHEMICAL

Universidade Federal de Ouro Preto

null

Moringa Oleifera Seed Peel Structure and Its Performance in Cementitious Composite

Ishihara, Marina Keiko

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract This article seeks to characterize the seed husk fiber of Moringa oleifera and understand its influence when added to a cementitious composite, in terms of mechanical performance. Moringa fibers were chemically and physically tested and were added to a cementitious composite. Specimens were molded for Ultrasonic Speed Pulse test and Uniaxial Compression Strength test, and subsequent observation in SEM. The results show a fiber with high lignin content and high absorption of water. Adding fiber to the composite, the water in the mixture is absorbed, which reduces the formation of hydrated cement compounds over time. Consequently, it results in a composite with low mechanical strength. The fiber/matrix interface analyzed in the micrographs is porous, has microcracks and a high concentration of calcium hydroxide. Despite this, the same lignin content that impairs mechanical strength in this composite is what makes the fiber resistant to weathering. More studies regarding the effectiveness of this quality should be carried out.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000800214&lng=en&tlng=en

34

scielo_articles/scl/1516-1439/S1516-14392021000800214.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Ishihara, Marina Keiko", "Silva, Guilherme Jorge Brigolini", "Finzi-Quintão, Cristiane M.", "Novack, Kátia Monteiro" ]

null

[ "Natural fiber composites", "Moringa oleifera", "fiber structure", "mortar", "cement composites" ]

null

[ "Universidade Federal de Ouro Preto", "Universidade Federal de Ouro Preto", "Universidade Federal de São João del-Rei", "Universidade Federal de Ouro Preto" ]

scl/1516-1439/S1516-14392021000800215.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000800215

10.1590/1980-5373-mr-2022-0049

ENGINEERING, CHEMICAL

Universidad Industrial de Santander

null

Evaluation Through SEM Image Processing of the Volumetric Fiber Content in Continuos Fiber-Reinforced Additive Manufacturing Composites

Díaz, J. G.

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

This work shows the estimation of the volumetric fiber content (Vf) using image processing techniques. The Vf is needed to establish mechanical properties of composites using the rule of mixtures or other more advanced prediction models for the mechanical properties. The proposed method is tested with images acquired for carbon, Kevlar, and fiberglass fiber bundles used in the fiber deposition modeling (FDM) in the additive manufacturing process. The fiber bundles are provided by Markforged ® and are used in the Markforged Two ® printer. Then, different gray threshold and segregation algorithms are convolved with the digitized images to to isolate matrix from fibers such that a separate fiber and matrix area counting can be done and an appropriate Vf can be established. Results obtained with image analysis are close to values reported using technical standards, hence validating the proposed method.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000800215&lng=en&tlng=en

28

scielo_articles/scl/1516-1439/S1516-14392021000800215.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Díaz, J. G.", "León-Becerra, J.", "Pertuz, A. D.", "González-Estrada, O. A.", "Jaramillo-Gutiérrez, M. I." ]

null

[ "Fiber content", "image treatment", "composites", "additive manufacturing", "Markforged" ]

null

[ "Universidad Industrial de Santander", "Universidad Industrial de Santander", "Servicio Nacional de Aprendizaje (SENA)" ]

scl/1516-1439/S1516-14392021000800216.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000800216

10.1590/1980-5373-mr-2022-0231

ENGINEERING, CHEMICAL

Universidade Federal do Rio Grande do Sul

null

Optimization of Cutting Parameters for Finish end Milling CFRP Under Vortex-Cooled Compressed Air

Klein, Rodrigo F.

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Carbon fiber reinforced plastics (CFRP) offer several advantages in the aeronautical and automotive industry due to their combination of lightweight, high strength, and corrosion resistance. CFRP parts are usually produced in near-net-shape; however, additional machining processes are often required for achieving desired dimensional accuracy and surface finish. Thus, this work evaluates the influence of the cutting parameters in CFRP end milling to generate a better surface finish. The experiment was designed using a three-factor, three-level Box-Behnken considering feed rate (f), axial depth of cut (ap), and cooling conditions (cc) as controllable factors, and roughness parameters (Ra, Rq, Rz, Rt) as response variables (the occurrence of defects was evaluated qualitatively). Results indicated a strong influence of the quadratic effect of axial depth of cut and its interactions with feed rate and cooling condition on the roughness values and a milder but significant influence of the feed rate and cooling conditions. Multivariate analysis returned the optimum level of input parameters (f= 0.21 mm/rev and ap= 0.8 mm with cooled compressed air), resulting in Ra= 1.58 µm, Rq= 1.98 µm, Rz= 9.39 µm, Rt= 13.63 µm. Also, no defects were observed after machining under the optimum conditions.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000800216&lng=en&tlng=en

58

scielo_articles/scl/1516-1439/S1516-14392021000800216.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Klein, Rodrigo F.", "Hoffmann, Nícholas", "Souza, André J.", "Rebelo, Franciele J.", "Amorim, Heraldo J." ]

null

[ "Carbon fiber reinforced plastic", "end milling", "surface roughness", "vortex-cooled compressed air" ]

null

[ "Universidade Federal do Rio Grande do Sul" ]

scl/1516-1439/S1516-14392022000100201.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100201

10.1590/1980-5373-mr-2020-0440

ENGINEERING, CHEMICAL

Universidade Federal de Pernambuco

null

Application of a Mix of Vegetables Residues as Inhibitor for Carbon Steel

Barreto, L.S.

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

This work investigates the synergistic use of Theobroma cacao (Cocoa), and Elaeis guineensis (Palm oil) as corrosion inhibitors for carbon steel in 0.5 mol.L-1 hydrochloric acid solution, in the absence and presence of different mixture concentrations of the studied compounds. The efficiency of corrosion inhibitors was studied by gravimetric tests and the corrosion resistance by electrochemical tests, such as electrochemical impedance spectroscopy (EIS) and polarization curves. The chemical composition of the cocoa bark powder and palm kernel cake powder was evaluated by Fourier transform infrared spectroscopy (FTIR). The results of the gravimetric tests showed an inhibition efficiency of 79% for the cocoa bark powder and 76% for palm kernel cake powder, however, the mixture of the compounds presented an inhibition superior to 94%, showing the great synergism between the studied species. These results corroborate the values obtained from EIS.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100201&lng=en&tlng=en

65

scielo_articles/scl/1516-1439/S1516-14392022000100201.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Barreto, L.S.", "Santos, A.M.", "de Almeida, T.F.", "Silva, D. R.", "Cotting, F.", "Capelossi, V.R." ]

null

[ "Corrosion", "inhibitors", "EIS", "FTIR", "Gravimetric tests", "Cocoa and palm oil" ]

null

[ "Universidade Federal de Pernambuco", "Universidade Estadual de Santa Cruz", "Universidade Federal do Recôncavo Baiano", "Universidade de São Paulo", "Universidade Federal de Minas Gerais" ]

scl/1516-1439/S1516-14392022000200101.xml

en

editorial

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000200101

10.1590/1980-5373-mr-2023-e002

ENGINEERING, CHEMICAL

Instituto de Pesquisas Energéticas e Nucleares

null

ICC INTERCORR WCO 2021: A Virtual Edition

Panossian, Zehbour

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000200101&lng=en&tlng=en

null

scielo_articles/scl/1516-1439/S1516-14392022000200101.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Panossian, Zehbour", "Costa, Isolda", "Rossi, Jesualdo Luiz" ]

null

[ "Instituto de Pesquisas Energéticas e Nucleares", "Instituto de Pesquisas Tecnológicas do Estado de São Paulo" ]

scl/1516-1439/S1516-14392022000100802.xml

en

correction

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100802

10.1590/1980-5373-mr-2021-0552er

ENGINEERING, CHEMICAL

null

Erratum: Electrodeposition of Chitosan on Ti-6Al-4V Surfaces: A Study of Process Parameters

null

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100802&lng=en&tlng=en

null

scielo_articles/scl/1516-1439/S1516-14392022000100802.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

null

scl/1516-1439/S1516-14392022000100801.xml

en

correction

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100801

10.1590/1980-5373-mr-2021-0016er

ENGINEERING, CHEMICAL

null

Erratum: Characterization of Plasma-deposited a-C:H:Si:F:N Films

null

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100801&lng=en&tlng=en

null

scielo_articles/scl/1516-1439/S1516-14392022000100801.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

null

scl/1516-1439/S1516-14392022000100394.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100394

10.1590/1980-5373-mr-2022-0238

ENGINEERING, CHEMICAL

Ataturk University

null

Microstructural Characterization and Wear Behavior of Porous Equimolar TiNbZr Medium-Entropy Alloys Scaffolds Produced by Mechanical Alloying

Karadeniz, Şükran

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Recently, there has been increasing importance on scaffold materials that could be used in biomaterials. In the present study, equimolar TiNbZr medium entropy alloys (MEAs) and porous TiNbZr alloy scaffolds were produced by mechanical alloying (MA) that is a powder metallurgy processing technique. The MA process was carried out using high energy planetary ball mill. Ammonium bicarbonate (NH4HCO3) at different percentage ratio was used as space holder to fabricate the porous TiNbZr scaffolds with using space-holder sintering method. Cold Isostatic Pressing (CIP) was performed for consolidation of mechanically alloyed powders. Finally, the green compact samples were sintered in tube furnace under vacuum atmosphere. The microstructural analyses, phase composition, porosity and density measurement, compression and microhardness tests and wear resistance of bulk alloys were examined. The X-Ray Diffraction (XRD) patterns of all samples indicated the dominant β-Ti phases and small amount of α-Ti phase. SEM (scanning electron microscope) images for porous TiNbZr alloy scaffolds demonstrated that porosity increased with increase of space holders amount. With the increasing porosity content, density, hardness, compressive strength and the elastic modulus of samples decreased while wear rate increased.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100394&lng=en&tlng=en

34

scielo_articles/scl/1516-1439/S1516-14392022000100394.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Karadeniz, Şükran", "Arslan, Ersin" ]

null

[ "Equimolar TiNbZr alloy", "Medium-entropy alloys", "Porous scaffolds", "Powder metallurgy", "Mechanical property", "Wear behavior", "Cold isostatic press", "Space-holder method", "Ammoniumhydrogen carbonate (NH4HCO3)" ]

null

[ "Ataturk University", "Istanbul Aydin University" ]

scl/1516-1439/S1516-14392022000100393.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100393

10.1590/1980-5373-mr-2022-0047

ENGINEERING, CHEMICAL

Manipal Academy of Higher Education

null

Alternate Thermomechanical Heat Treatment Cycles for the Enhancement in Hardness and Tensile Properties of Commercial Grade AA6061

Sadanand, Ramakrishna Vikas

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Numerous research incorporating precipitation hardening and/or strain hardening on Al-Mg-Si alloys has demonstrated improved mechanical properties in the alloys. However, there is a lack of research on how these processes can be combined efficiently to provide better strength and hardness for the alloys. The present study describes the effects of low temperature thermomechanical treatment (LTMT - combination of conventional age hardening and strain/work hardening) carried at two isothermal aging temperatures on the hardness and strength of the aluminium alloy 6061 (AA6061). Further, an innovative LTMT process is also proposed, which aims at further enhancing the mechanical properties of the alloy. The study revealed the increase in degree of deformation improved the strength and hardness of the alloy with reduced aging time. The effect of the degree of deformation, pre-deformation, and alternate deformation and aging cycles on the hardness and strength of the alloy was studied with the help of fracture surface analysis.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100393&lng=en&tlng=en

37

scielo_articles/scl/1516-1439/S1516-14392022000100393.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Sadanand, Ramakrishna Vikas", "Sharma, Sathyashankara", "Prabhu, P. R." ]

null

[ "AA6061", "Al-Mg-Si alloy", "Low Temperature Thermomechanical Treatment", "Hardness", "Cold Rolling", "Fractography" ]

null

[ "Manipal Academy of Higher Education", "Manipal Academy of Higher Education" ]

scl/1516-1439/S1516-14392022000100392.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100392

10.1590/1980-5373-mr-2022-0078

ENGINEERING, CHEMICAL

Corporación Universitaria Comfacauca

null

Tribological Evaluation of Ferritic-Austenitic Stainless Steel Coatings with Different Percentages of Silver

Peña, Claudia Liliana España

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Stainless steels have been evaluated in the form of coatings or thin films deposited using magnetron sputtering in various investigations. In most of these investigations, mainly the microstructural evaluation of this type of coating has been reported, while the evaluation of wear resistance has not been widely studied. In the present investigation, ferritic-austenitic stainless steel coatings with different percentages of silver were deposited by means of unbalanced DC magnetron sputtering. A stainless steel target doped with different numbers of silver inserts (0, 1, 2, 3, and 4 inserts) was used, obtaining coatings with silver percentages of up to 7.7 at. %, in order to evaluate their tribological properties. During the synthesis, the first layer of the bilayer was deposited with argon and the other in an atmosphere of argon and nitrogen. The structure of the coatings was evaluated by use of X-ray diffraction (XRD), and the morphology and the chemical composition were studied by means of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively. The hardness was tested through nanoindentation, and the wear test was carried out using the pin-on-disc technique. The wear tracks were evaluated via profilometry, SEM, and EDS. In general, the deposited films exhibited BCC and FCC phases and a compact morphology, as well as good adherence to the substrate. The results of the evaluation of the mechanical properties revealed an increase in the hardness of the coatings when the silver content was augmented, obtaining values of 9.8 GPa and 12.1 GPa for coatings with 0 and 4 silver inserts, respectively. Likewise, it was found that the wear resistance of coatings was higher, up to two orders of magnitude compared to the 316L stainless steel substrate. Finally, the wear rate of the multilayers decreased slightly with an increase in the percentage of silver in the films produced, up to an order of magnitude for the coating with 4 silver inserts relative to the coating with 0 silver inserts.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100392&lng=en&tlng=en

48

scielo_articles/scl/1516-1439/S1516-14392022000100392.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Peña, Claudia Liliana España", "Flórez, Jhon Jairo Olaya", "Recco, Abel André Cândido" ]

null

[ "Multilayer", "stainless Steel", "wear", "sputtering" ]

null

[ "Corporación Universitaria Comfacauca", "Universidad Nacional de Colombia", "Universidade do Estado de Santa Catarina" ]

scl/1516-1439/S1516-14392022000100391.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100391

10.1590/1980-5373-mr-2022-0336

ENGINEERING, CHEMICAL

Universidade Federal do Rio Grande do Sul

null

Artificial Neural Networks for Producing a Low-Cost Austempered Ductile Iron

Hofmam, Diogo

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Two artificial neural networks (ANNs) were developed for producing an austempered ductile iron (ADI) with low-cost chemical composition and mechanical properties as per ASTMA897/897M-16-grade-1050/750/07 standard. Thus, the first ANN predicted the chemical composition range within the lowest cost and required mechanical properties. Next, in the second ANN, the resulting values from the first ANN were refined considering the target chemical composition suggested in the standard. Moreover, mechanical properties and microstructural analyses were undertaken in the ADI produced to support the ANNs’ findings. Hence, ANNs can be used to make a standard-compliant ADI and achieve cost savings.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100391&lng=en&tlng=en

55

scielo_articles/scl/1516-1439/S1516-14392022000100391.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Hofmam, Diogo", "Ramos, Fabiano Dornelles", "Lemos, Guilherme Vieira Braga", "Lessa, Cleber Rodrigo de Lima" ]

null

[ "Austempered ductile iron", "Artificial neural network", "Mechanical properties", "Cost-savings" ]

null

[ "Universidade Federal do Rio Grande do Sul", "Universidade Federal de Santa Maria", "Instituto Federal do Rio Grande do Sul", "Instituto Federal do Rio Grande do Sul" ]

scl/1516-1439/S1516-14392022000100390.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100390

10.1590/1980-5373-mr-2022-0259

ENGINEERING, CHEMICAL

Universidade Estadual de Ponta Grossa

null

Influence of the Number of Dimensions in the Impedance Spectroscopy Simulation of a YSZ Electrolyte

Ouba, Ana Kaori de Oliveira

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

The use of computer simulation to predict the behavior of devices and materials allows for the acceleration of system operation and reduces costs, as it eliminates the need to build prototypes for testing. This work proposes the construction of 3 models with different complexities to simulate the electrical behavior of a solid electrolyte fuel cell. Experimental data were compared with simulation data. The experimental data were obtained from the production of a solid YSZ by tape casting, sintered at 1550 °C. The material was characterized using impedance spectroscopy in atmospheric air. From the experimental data, a computer simulation was conducted by using commercial code (COMSOL Multiphysics v.5.4). The construction of the model was developed to 1D, 2D axisymmetric and 3D dimensions to simulate an electrolyte to use in cylindrical planar SOFC. Nyquist Impedance graphics were plotted for the three geometries in comparison with the experimental value. No variation was observed between the curves obtained by the different geometries for the same interface. In other words, the interface complexity did not interfere in the result obtained for the same experimental data. We concluded that the 1D model is ideal to predict the influence of operational parameters because it is simpler and saves analysis time, maintaining the reliability and accuracy of the results.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100390&lng=en&tlng=en

39

scielo_articles/scl/1516-1439/S1516-14392022000100390.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Ouba, Ana Kaori de Oliveira", "Chinelatto, Adilson Luiz", "Borcezi, Janaina Semanech", "Neitzel, Ivo", "Chinelatto, Adriana Scoton Antonio" ]

null

[ "Impedance spectroscopy", "solid oxide fuel cell", "electrolyte", "simulation model" ]

null

[ "Universidade Estadual de Ponta Grossa", "Faculdade de Telêmaco Borba" ]

scl/1516-1439/S1516-14392022000100389.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100389

10.1590/1980-5373-mr-2022-0227

ENGINEERING, CHEMICAL

Universiti Teknologi MARA

null

Structural and Optical Properties of TIPS Pentacene Thin Film Exposed to Gamma Radiation

Rasmidi, Rosfayanti

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

This study investigates the effects of Gamma-irradiation on the structural, morphological and optical properties of 3,16-bis(tri isopropyl silylethynyl)pentacene (TIPS Pentacene) organic semiconductor films. The TIPS Pentacene thin films were irradiated at 10 to 300 kGy at a dose rate of 1.58 kGy/hr. The films were characterized using X-Ray Diffractometer (XRD), Atomic Force Microscopy (AFM) and Ultraviolet-Visible Spectroscopy (UV-Vis). The XRD analysis showed that the pre-irradiated thin films were of crystalline structure, indicating a broad wave diagram. The XRD and AFM results show that these variations can be attributed to the radiation-induced local heating and microscopic atomic mobility. Based on the UV-Vis results, the thin films exhibit approximately 70% optical transmittance in the visible region at pre-irradiation. At post-irradiation, optical transmittance decreased to 55% at the maximum absorbed dose. The corresponding optical bandgap decreased from 1.87 to 1.50 eV after a total ionizing dose of 300 kGy. The findings showed that TIPS Pentacene thin film has good mitigation towards gamma irradiation and can withstand harsh radiation while retaining its semiconductor properties. It is a potential candidate for flexible electronics for space applications.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100389&lng=en&tlng=en

47

scielo_articles/scl/1516-1439/S1516-14392022000100389.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Rasmidi, Rosfayanti", "D. S., Mivolil", "Chee, Fuei Pien", "Juhim, Floressy", "Rumaling, Muhammad Izzuddin", "Salleh, Saafie", "Eswar, K.A.", "Salleh, Khairul Anuar Mohd", "Ibrahim, Sofian" ]

null

[ "TIPS Pentacene", "gamma radiation", "radiation effects", "organic semiconductor" ]

null

[ "Universiti Teknologi MARA", "Universiti Malaysia Sabah", "Universiti Teknologi MARA Sabah Branch", "Malaysia Nuclear Agency for Non-destructive Testing", "Malaysia Nuclear Agency" ]

scl/1516-1439/S1516-14392022000100388.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100388

10.1590/1980-5373-mr-2022-0391

ENGINEERING, CHEMICAL

Universidade Tecnológica Federal do Paraná

null

Heterogeneous Photocatalysis with Niobium Doped-Titanium Substrates Treated by Plasma Electrolytic Oxidation

Orsetti, Fábio R.

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Plasma Electrolytic Oxidation (PEO) was employed for the generation of porous niobium-containing surfaces with enhanced photocatalytic activity. Pulses of 500 and 600 V, with a repetition rate of 60 Hz, were applied to titanium disks immersed in niobium-containing electrolytic solutions. The treatment time ranged from 180 to 600 s, and the surface morphology was analyzed by scanning electron microscopy, while X-ray diffraction was employed in the evaluation of crystallographic structure. The optical gap of the samples was determined from UV-Vis reflection spectra, and an automated goniometer was used for contact angle and surface energy measurements. More than 35% of Nb has been incorporated into the samples. Under certain conditions, the treatments resulted in a reduction of the optical gap from 3.18 to 2.63 eV as compared to as-received samples. Photocatalytic degradation rates of methylene blue as high as 70% have been reached after 120 minutes under irradiation with UV-Vis light.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100388&lng=en&tlng=en

31

scielo_articles/scl/1516-1439/S1516-14392022000100388.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Orsetti, Fábio R.", "Gonçalves, Thaís M.", "Sottovia, Lívia", "Figueiredo, Elaine B.", "Ferrari, Ana M.", "Rangel, Elidiane C.", "Cruz, Nilson C." ]

null

[ "Photocatalytic activity", "titanium", "niobium oxide", "plasma electrolytic oxidation", "PEO" ]

null

[ "Universidade Tecnológica Federal do Paraná", "Universidade Estadual Paulista" ]

scl/1516-1439/S1516-14392021000200206.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000200206

10.1590/1980-5373-mr-2020-0238

ENGINEERING, CHEMICAL

Universidade Federal de Pernambuco

null

Characterization of Poly(Ethylene Terephthalate) by Torque Rheometry

Andrade, Daniella Stepheny Carvalho

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Polymer processing parameters may considerably affect final product characteristic as, if properly chosen, these parameters may lead to products with optimal properties. The aim of this work is to evaluate the rheological characteristics of poly(ethylene terephthalate) (PET) by torque rheometry, as well as to estimate its incipient degradation rate during processing in an internal laboratory mixer. In order to estimate the temperature coefficient of the viscosity (β), and the pseudoplasticity index (n) of PET, two sets of experiments need to be performed. In the first one, the polymer is processed at three different temperatures at a single rotor speed for 10 min, getting temperature coefficient of the viscosity equal to β = 0.053 °C-1. In the second set of experiments, the resin (PET) is processed at a single temperature at six different rotor speeds for the same time interval and the pseudoplasticity index was determined, n = 0.78. From the results obtained, it is possible to indicate the internal mixer as an equipment not only for mixing polymers or composites, but as a tool for determining important rheological variables for predicting degradative processes.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000200206&lng=en&tlng=en

23

scielo_articles/scl/1516-1439/S1516-14392021000200206.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Andrade, Daniella Stepheny Carvalho", "Canedo, Eduardo Luís", "Carvalho, Laura Hecker de", "Barbosa, Renata", "Alves, Tatianny Soares" ]

null

[ "Poly(ethylene terephthalate)", "Rheology", "Viscosity", "Degradation" ]

null

[ "Universidade Federal de Pernambuco", "Universidade Federal de Campina Grande", "Universidade Federal do Piauí" ]

scl/1516-1439/S1516-14392021000300206.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300206

10.1590/1980-5373-mr-2020-0477

ENGINEERING, CHEMICAL

Unigal Usiminas

null

Numerical Simulation of Zinc Flow in Different Layouts of Galvanization Pot

Vieira, Ronaldo Rodrigues

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

The production of galvanized steel with zinc (GI) presents great challenges due to the high demand for surface quality required for its applications. The automotive segment is one of the largest consumers of this type of product. In hot dip galvanizing lines, the main defect that affects the surface quality of the coatings is the dragging of dross particles. Some studies have already been carried out to understand the formation of these particles inside the zinc bath, however little is known about the trajectory of these particles in relation to the pot layout. In this study, two types of layout were simulated to assess how this interferes with the flow of zinc. In the results it was verified that, the position of the heating inductor significantly modifies the trajectory of the dross particles.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300206&lng=en&tlng=en

18

scielo_articles/scl/1516-1439/S1516-14392021000300206.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Vieira, Ronaldo Rodrigues", "Eleutério, Henrique Lacerda", "Oliveira, Thalisson Gustavo de", "Bagatini, Maurício Covcevich", "Tavares, Roberto Parreiras" ]

null

[ "Numerical Simulation", "Mathematical Model", "Hot Dip Galvanizing", "Dross" ]

null

[ "Unigal Usiminas", "Centro de Pesquisa e Desenvolvimento da Usiminas", "Instituto ESSS", "Universidade Federal de Minas Gerais" ]

scl/1516-1439/S1516-14392021000100213.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100213

10.1590/1980-5373-mr-2020-0359

ENGINEERING, CHEMICAL

Universidade Federal da Paraíba

null

Selective Surfaces of Ilmenite for Use in Solar Absorbers

Sousa, Gustavo César Pamplona de

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The world is moving at a fast pace in the consumption of non-renewable natural resources, causing several ecological problems. The search for the cost reduction by implementing renewable energies implies in the optimization of the manufacturing processes parameters of consolidated technologies, such as solar thermal energy collectors. One of the applications of selective surfaces is to improve performance of solar absorbers. The purpose of this work is to produce selective coatings with high absorption in range of UV/Vis and low emittance in the IR range. It was prepared a selective surface composed of ilmenite deposited on substrates of AISI 304 stainless steel using technique of cathodic cage plasma nitriding/deposition for application in solar thermal absorbers. Ilmenite was initially characterized by X-Ray Diffractometry (XRD), X-Ray Fluorescence (FRX) and Thermal Analysis (TGA). The coatings produced were optically characterized in range UV/Vis/IR and emittance and data on the roughness parameters of the films were obtained by Optical Profilometry. Selective surfaces with high solar absorbance (87%) compared with state-of-the-art commercial ones (70-80%) and low thermal emission (14%) compared with state-of-the-art commercial ones (20-30%) were obtained by validating the potential of ilmenite to produce selective surfaces for thermal solar collectors.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100213&lng=en&tlng=en

15

scielo_articles/scl/1516-1439/S1516-14392021000100213.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Sousa, Gustavo César Pamplona de", "Gomes, Kelly Cristiane", "Amorim Júnior, Wanderley Ferreira de", "Duarte, Raimundo Nonato Calazans" ]

null

[ "selective surfaces", "solar absorbers", "ilmenite", "hollow cathode deposition" ]

null

[ "Universidade Federal da Paraíba", "Universidade Federal da Paraíba", "Universidade Federal de Campina Grande" ]

scl/1516-1439/S1516-14392020000600224.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392020000600224

10.1590/1980-5373-mr-2020-0316

ENGINEERING, CHEMICAL

Lanzhou University of Technology

null

Application of Nanometer Antimony Trioxide Modified by Dioctyl Phthalate in Polyvinyl Chloride Flame Retardant Materials

Xu, Jian-lin

2,020

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

In order to improve the compatibility and dispersion of antimony trioxide nanoparticles (nano-Sb2O3) in polyvinyl chloride (PVC) and improve the comprehensive properties of PVC, a novel type of nano-Sb2O3/DOP/PVC composites was prepared by using nano-Sb2O3 modified by dioctyl phthalate (DOP) as flame retardant and the mechanical properties and flame-retardant properties of the composites were studied. The results indicated that nano-Sb2O3 particles modified by appropriate DOP could improve the flame retardancy and tensile strength of PVC matrix composites due to good dispersibility and interface compatibility of nano-Sb2O3 in PVC matrix. The PVC matrix composites containing 2 wt% nano-Sb2O3 particles modified by DOP with 5 wt% of usage had excellent flame retardancy, which LOI was 29.8% and its UL94 grade was V-0 level. And the heat release rate,smoke production rate, CO content and CO2 content of the composites was significantly reduced. Meanwhile, the tensile strength and Young's modulus of the composites were 15.9 MPa and 2.1 GPa, respectively.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392020000600224&lng=en&tlng=en

21

scielo_articles/scl/1516-1439/S1516-14392020000600224.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Xu, Jian-lin", "Lin, Yong-gang", "Yang, Wen-long", "Kang, Cheng-hu", "Niu, Lei" ]

null

[ "polyvinyl chloride", "antimony trioxide nanoparticles", "dioctyl phthalate", "composites", "flame retardancy", "mechanical properties" ]

null

[ "Lanzhou University of Technology", "Lanzhou University of Technology", "Hexi University" ]

scl/1516-1439/S1516-14392021000300211.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300211

10.1590/1980-5373-mr-2020-0431

ENGINEERING, CHEMICAL

Universidade Federal Fluminense

null

Modeling and Numerical Validation of Stress-Strain Curves of Maraging Steels, Grades 300 and 350 Under Hydrogen Embrittlement

Chales, R.

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Maraging steels are ferrous alloys with Ni, Co, Mo, and Ti additions. These materials are a special class of ultra high mechanical strength steels with wide and special applications in strategic areas, which makes their knowledge very valuable. Computational advances allowed to analyze the behavior of these materials numerically, using the finite element method and developing mathematical models that can represent numerically its mechanical behavior. The present work has the objective of surveying the mechanical properties of maraging steels 300 and 350 by slow strain rate tensile (SSRT) tests, after the solution treatment at 1183K for 1h. Additionally, it was evaluated the hydrogen embrittlement in samples tested by SSRT under cathodic protection with a potential -1.2 VSCE in 3.5% NaCl solution. The study was complemented with detailed fractographic analysis. This work also presents the analysis of representative models by use of Hollomon, Swift, Voce and coupled Swift-Voce equations to describe the strain-hardening behavior. Compared to the others, the Voce’s model was the one which best fitted the experimental results, with values of R2 higher than 0.992. Through the variation of the chemical composition found in the different grades of maraging steels, this work contemplates the creation of a generalized Voce model based on the variation of the Ti content. The work concludes presenting the generalized Voce model proposed and a numerical analysis of the SSRT results with a good accuracy of the strain-hardening response.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300211&lng=en&tlng=en

39

scielo_articles/scl/1516-1439/S1516-14392021000300211.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Chales, R.", "Cardoso, A.S.M.", "Pardal, J.M.", "Tavares, S.S.M.", "Silva, M.M.", "Reis, D.A.P." ]

null

[ "Maraging steel", "slow strain rate test", "embrittlement effect", "modelling", "finite element analysis" ]

null

[ "Universidade Federal Fluminense", "Centro Federal de Educação Celso Suckow", "Instituto Tecnológico de Aeronáutica", "Universidade Federal de São Paulo" ]

scl/1516-1439/S1516-14392021000300210.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300210

10.1590/1980-5373-mr-2020-0387

ENGINEERING, CHEMICAL

Universidad Autónoma de Ciudad Juárez

null

Synthesis and Characterization of Carbon Aerogels Electrodes Modified by Ag2S Nanoparticles

Martínez, Ramsés R. García

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

In this work, electrodes based on carbon aerogels (CA) modified by Ag2S nanoparticles (NPs) were synthesized by sputtering and solid-vapor reactions. Nanoparticles were identified as silver sulfide (acanthite phase) and their size was controlled by the sputtering time (5s deposition- 8.65 nm ± 1.74 nm, 7s deposition- 12.78 nm ± 8.53 nm and 45 s deposition- 21.35 nm ± 10.07 nm). It was found that the electrodes properties vary according to the Ag2S NPs sizes. All modified electrodes exhibited an improved REDOX reactions reversibility, enhanced optical properties (0.97 to 1.22 eV optical bandgap) and electrical conductivity (8.60-9.40 S/cm) when compared with pure carbon aerogel electrodes (1.4 eV, 8.20 S/cm).

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300210&lng=en&tlng=en

45

scielo_articles/scl/1516-1439/S1516-14392021000300210.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Martínez, Ramsés R. García", "González, Claudia Alejandra Rodríguez", "Hernández-Paz, Juan Francisco", "Vega, Florinda Jiménez", "Montes, Héctor Camacho", "Armendáriz, Imelda Olivas" ]

null

[ "Carbon aerogel", "Ag2S nanoparticles", "electrodes" ]

null

[ "Universidad Autónoma de Ciudad Juárez", "Universidad Autónoma de Ciudad Juárez" ]

scl/1516-1439/S1516-14392021000300209.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300209

10.1590/1980-5373-mr-2021-0078

ENGINEERING, CHEMICAL

Al-Balqa Applied University

null

Processing and Characterization of Surface Treated Chicken Eggshell and Calcium Carbonate Particles Filled High-Density Polyethylene Composites

Dweiri, Radwan

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The use of the biowaste chicken eggshell (ES) particles as an alternative filler for the inorganic calcium carbonate (CC) in polymeric materials was investigated in this study. ES and CC were chemically surface treated with stearic acid by dry and wet methods. Composites of ES and CC filled high-density polyethylene (HDPE) was prepared via melt mixing and their thermal-mechanical- and flow behavior was characterized. FTIR results showed some changes in the chemical structure of SA treated ES and CC. The mechanical properties of the composites fluctuated in their values based on the SA treatment method. The wet-treated HDPE/ES composites showed higher tensile and flexural strengths compared to that of the untreated ones which were also higher than their counterparts of HDPE/CC composites. The treated-ES particles motivated the crystallization process of HDPE compared to the untreated-ES and better flow properties was reported for composites with higher crystallinity and for HDPE/CC composites. Morphological observations showed particles agglomeration and void existence which led to deterioration of the mechanical properties.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300209&lng=en&tlng=en

56

scielo_articles/scl/1516-1439/S1516-14392021000300209.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Dweiri, Radwan" ]

null

[ "polymer composites", "surface modification", "chemical analysis", "thermal analysis", "mechanical testing", "microscopy" ]

null

[ "Al-Balqa Applied University" ]

scl/1516-1439/S1516-14392021000300207.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300207

10.1590/1980-5373-mr-2020-0434

ENGINEERING, CHEMICAL

Dalian Maritime University

null

Synthesis of WO3 Nanorods and Their Excellent Ethanol Gas-Sensing Performance

Xiao, Jingkun

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract WO3 nanorods were synthesized via a simple hydrothermal approach. Their microstructure and morphology were analyzed with x-ray diffraction, scanning electron microscope and x-ray photoelectron spectroscopy. The effects of reaction temperature, reaction time, and citric acid concentration, on the gas-sensing performance of WO3 nanorods were investigated. The optimized response value of WO3 sensor to ethanol gas (100 ppm) was 26.48, with a response time of 1 s under a low operating temperature (160 °C). The recovery capability and stability of the gas sensor were tested and discussed. Additionally, the working principle of WO3 sensor was proposed. In comparison to the sensors published by previous researchers, the WO3 sensor has shown great potential.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300207&lng=en&tlng=en

31

scielo_articles/scl/1516-1439/S1516-14392021000300207.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Xiao, Jingkun", "Che, Yanhan", "Lv, Bowen", "Benedicte, Massamba-Courtoisjoanes", "Feng, Guoqing", "Sun, Tianjun", "Song, Chengwen" ]

null

[ "WO3", "gas sensor", "response", "nanorods", "ethanol" ]

null

[ "Dalian Maritime University", "Dalian Maritime University" ]

scl/1516-1439/S1516-14392021000300205.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300205

10.1590/1980-5373-mr-2020-0454

ENGINEERING, CHEMICAL

Universidade Federal de Pernambuco

null

Kinetic Study of a Bacterial Cellulose Production by Komagataeibacter Rhaeticus Using Coffee Grounds and Sugarcane Molasses

Souza, Karina Carvalho de

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Biotechnology can be used to convert waste into valuable products. In this context, there is bacterial cellulose (BC), a natural biopolymer that can be transformed into several useful materials, but its production is limited due to the high cost of the culture media used for its industrialization. In this work, BC was produced from the bacteria Komagataeibacter rhaeticus, using coffee grounds, sugarcane molasses and ethanol. The experiments were carried out under static conditions. The products were collected every 48 h, with a total period of 240 h. The maximum BC production (11.08 g.L-1) was obtained in a culture medium supplemented with coffee powder, hydrolyzed cane molasses and the addition of 1% (v/v) ethanol. The results show that the use of different carbon sources of the evaluated by-products are viable alternatives in reducing costs in BC production.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300205&lng=en&tlng=en

39

scielo_articles/scl/1516-1439/S1516-14392021000300205.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Souza, Karina Carvalho de", "Trindade, Nicolas Mattos", "Amorim, Júlia Didier Pedrosa de", "Nascimento, Helenise Almeida do", "Costa, Andréa Fernanda Santana", "Henrique, Mariana Alves", "Caetano, Viviane Fonseca", "Sarubbo, Leonie Asfora", "Vinhas, Glória Maria" ]

null

[ "Bacterial cellulose", "Biopolymer", "Coffee grounds", "Komagataeibacter rhaeticus", "Sugarcane molasses" ]

null

[ "Universidade Federal de Pernambuco", "Universidade Federal de Pernambuco", "Universidade Federal de Pernambuco", "Universidade Católica de Pernambuco" ]

scl/1516-1439/S1516-14392021000200227.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000200227

10.1590/1980-5373-mr-2020-0409

ENGINEERING, CHEMICAL

Aristotle University of Thessaloniki

null

Microstructural and Finite Element Analysis - Assisted Nanomechanical Characterization of Maize Starch Nanocomposite Films

Mansour, G.

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Biocomposite films were prepared using normal maize starch plasticized with glycerol and water and sodium montmorillonite clay particles employing the solution mixing procedure. Scanning electron microscopy (SEM), X-ray diffraction (XRD), three-dimensional profilometry and tensile along with nanoindentation tests assisted with a Finite Element Analysis (FEA) were used for the assessment of starch-based films with various percentages of nanoclay particles. XRD analysis revealed intercalation of the test specimens while their morphology was ascertained using SEM/EDX. The FEA results were compared with the experimental measurements from nanoindentation and tensile tests. A satisfactory correlation was obtained between the experimental measurements and the computational models, demonstrating FEA-assisted nanoindentation as a useful technique for assessment, showing the effect of the different nanoclay concentrations on the mechanical properties.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000200227&lng=en&tlng=en

37

scielo_articles/scl/1516-1439/S1516-14392021000200227.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Mansour, G.", "Zoumaki, M.", "Tsongas, K.", "Tzetzis, D." ]

null

[ "Biodegradable Nanocomposites", "Nanoindentation", "Finite Element Analysis", "Mechanical Properties", "Starch", "Nanoclays" ]

null

[ "Aristotle University of Thessaloniki", "International Hellenic University" ]

scl/1516-1439/S1516-14392021000300204.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300204

10.1590/1980-5373-mr-2020-0447

ENGINEERING, CHEMICAL

Universidade Federal do Paraná

null

Microstructure and Wear Behavior of NbC-Reinforced Ni-Based Alloy Composite Coatings by Laser Cladding

Pizzatto, Alex

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract This work aims to evaluate the influence of laser power and reinforcement feeding rate on the microstructure, hardness, and wear behavior of NbC-reinforced Hastelloy C276TM alloy composite coatings. From a dual feeding system, one-step metal-matrix composite coatings were deposited with 10, 30, and 50% mass feeding of NbC powder with laser powers of 1.5 and 3.0 kW. Coatings deposited with 1.5 kW and 30% NbC showed some degree of porosity due to a combination of NbC feeding rate and melting pool temperature. Laser power and NbC feeding rate altered the melting efficiency and substrate burn-in shape, remarkably influencing the dilution. The composite microstructure was comprised of Ni-γ (FCC) dendrites with interdendritic network carbide which, in turn, ranged from lamellar-like M6C to blocky-like conjugated MC-M23C6 carbide. Primary petaloid-like MC [Nb] carbide was formed from a 30% reinforcement rate on, whilst a considerable number of unmelted particles was observed for 50%. The higher the reinforcement feeding rate, the higher the carbide fraction and better wear performance of low heat-input specimens. Synthesis with high heat-input sheds a light on the deleterious effect of the dilution and is not an option to enhance the wear performance.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300204&lng=en&tlng=en

36

scielo_articles/scl/1516-1439/S1516-14392021000300204.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Pizzatto, Alex", "Teixeira, Moises Felipe", "Rabelo, Alexsandro", "Falcade, Tiago", "Scheid, Adriano" ]

null

[ "Metal-Matrix Composite", "Nickel-based Superalloy", "NbC Reinforcement", "Microstructure", "Wear" ]

null

[ "Universidade Federal do Paraná", "Instituto SENAI de Inovação", "Universidade Federal do Rio Grande do Sul" ]

scl/1516-1439/S1516-14392021000300203.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300203

10.1590/1980-5373-mr-2020-0417

ENGINEERING, CHEMICAL

Instituto Federal de Alagoas

null

Role of Silicon in the Microstructural Development and Properties of Ti-15Nb-xSi Alloys for Biomedical Applications

Tavares, Andrea Macleybiane Gois

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Ti-Nb alloys are attractive for biomedical implants and the addition of Si can lead to an improved set of properties. This study investigates the effect on the microstructures and properties of solution-treated Ti-15Nb-xSi alloys followed by furnace cooling (FC), and water quenching (WQ). Based on the results, Si acts as a β-stabilizing element by increasing the β volume fraction from 13%–36% in FC samples to a range from 0%–0.55% Si. The elastic modulus decreased under both conditions and reached approximately 63 GPa in WQ samples with 0.35% Si due to an increased α” unit cell volume. On the other hand, hardness increased with increased Si content under FC and WQ conditions to a maximum of 313 HV in the WQ sample containing 0.55% Si.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300203&lng=en&tlng=en

50

scielo_articles/scl/1516-1439/S1516-14392021000300203.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Tavares, Andrea Macleybiane Gois", "Souza, Edvaldo Alves de", "Silva, Marcio Sangali Cristino da", "Matos, Gusttavo Reis Leite", "Batista, Wilton Walter", "Souza, Sandra Andreia Stwart de Araujo" ]

null

[ "Ti alloys", "biomaterial", "Vickers hardness", "elastic modulus" ]

null

[ "Instituto Federal de Alagoas", "Universidade Federal de Sergipe", "Universidade Estadual de Campinas", "Universidade Federal de Sergipe" ]

scl/1516-1439/S1516-14392021000300202.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300202

10.1590/1980-5373-mr-2021-0055

ENGINEERING, CHEMICAL

Anhui University of Technology

null

Investigation on Internal Crack Defects in Medium Carbon Steel by Soft Reduction

Ali, Naqash

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract This paper investigated the effect of soft reduction amount increasing from 1-4mm with a cooling time of 120s and 180s to reduce the internal crack defects by analyzing the microstructure, crack morphology, extent and nature of grain boundary ferrite, centre macrosegregation, and fracture surfaces in medium carbon steel. It was found that the large extent of grain boundary ferrite with coarse morphology weakens the bonding force of the PAGB and makes it brittle with the initiation of micro-cracks. The sever centre carbon macrosegregation of 1.3 takes place at cooling time of 180s with different reduction amounts, which becomes homogeneous at cooling time of 120s. The results show that the length of inter-granular and trans-granular cracks reaches 20mm with the carbon macrosegregation index of 1.3. The carbon macrosegregation index of 1.3 with a small fraction of 15% is enough to deteriorate the centre macrostructure of the ingot. The cleavage facet size of fracture surfaces is remarkably decreased below 100um at soft reduction parameters of 2mm/120s, 3mm/120s, and 4mm/120s with micro-cracks less than 100um, which reveals that the microstructure of specimens with these soft reduction parameters is more resistant to the cracks propagation.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300202&lng=en&tlng=en

25

scielo_articles/scl/1516-1439/S1516-14392021000300202.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Ali, Naqash", "Zhang, Liqiang", "Zhou, Hongwei", "Zhao, Aonan", "Zhang, Chaojie", "Fu, Kaixuan", "Cheng, Jinqi" ]

null

[ "Medium carbon steel", "soft reduction", "internal crack defects", "grain boundary ferrite", "carbon macrosegregation" ]

null

[ "Anhui University of Technology", "Anhui University of Technology," ]

scl/1516-1439/S1516-14392021000300201.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000300201

10.1590/1980-5373-mr-2020-0062

ENGINEERING, CHEMICAL

Instituto Federal de Santa Catarina

null

The Influence of Surface Condition on the Electrochemical Properties of ASTM F138 Steel for Biomedical Applications

Marques, Fernando Michelon

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

The aim of this paper was to determine the influence of machining parameters on the surface layer, and consequently on the electrochemical properties, of ASTM F138 austenitic stainless steels. Eight different surface conditions were generated in cylindrical samples by turning and polishing. The surface was characterized by surface roughness Ra and Rt, Vickers microhardness and microstructural characteristics. Cyclic voltammetric tests were performed to evaluate the potential of repassivation and pitting. The surfaces were analyzed by Scanning Electron Microscopy after the electrochemical tests were performed. The cutting parameters were identified to have a significant influence, and the feed rate was as influential as the depth of cut. The use of polishing alone is not sufficient to ensure that a surface has good surface integrity. Even with the polishing application, usually used to produce prostheses, a significant reduction in corrosion resistance occurs if care is not taken to minimize surface machining damage. Corrosion resistance is lower and pitting nucleation is higher in the samples with no polishing and with more severe machining parameters. The tests indicated that softer machining parameters can contribute to an increase in the life of implantable components, reducing the probability of localized corrosion, as well as improving the mechanical properties of prostheses.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000300201&lng=en&tlng=en

18

scielo_articles/scl/1516-1439/S1516-14392021000300201.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Marques, Fernando Michelon", "Rocha, Alexandre da Silva", "Santos, Giovanni Rocha", "Wolfart Junior, Mario", "Costa, Rodrigo Cardoso", "Ferreira, Jane Zoppas" ]

null

[ "Stainless steel", "corrosion", "machining parameters", "surface integrity" ]

null

[ "Instituto Federal de Santa Catarina", "Universidade Federal do Rio Grande do Sul", "Instituto Federal Catarinense" ]

scl/1516-1439/S1516-14392021000200229.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000200229

10.1590/1980-5373-mr-2020-0457

ENGINEERING, CHEMICAL

Universidade de São Paulo

null

3Y-TZP DLP Additive Manufacturing: Solvent-free Slurry Development and Characterization

Camargo, Italo Leite de

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Vat photopolymerization (VP) stands out among ceramic additive manufacturing processes for its ability to print sub-100 micrometer complex features. One of the main challenges of this process is the preparation of a homogeneous and stable ceramic slurry with a high solid load and low viscosity. In this work, different dispersants and resins were tested, aiming to provide a solvent-free slurry suitable for DLP additive manufacturing. Disperbyk-111 and PEGDA 250 stood out in the tests, providing a 40 vol% ceramic slurry with no noticeable sedimentation and viscosity of 2.3 Pa.s at 30 s-1 despite the relatively high specific surface area (15 m2/g) of the 3Y-TZP powder used compared to powders usually used for VP slurries. The adsorption of Disperbyk-111 on ceramic particles surface was investigated by FTIR. Finally, ceramic bodies were 3D printed, debound and sintered at 1500 ºC for 2 h, confirming the ability to manufacture detailed dense ceramic parts.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000200229&lng=en&tlng=en

56

scielo_articles/scl/1516-1439/S1516-14392021000200229.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Camargo, Italo Leite de", "Erbereli, Rogério", "Taylor, Hayden", "Fortulan, Carlos Alberto" ]

null

[ "Rheological behavior", "Stereolithography", "3d printing", "Digital light processing", "Zirconia" ]

null

[ "Universidade de São Paulo", "Instituto Federal de Educação", "University of California" ]

scl/1516-1439/S1516-14392021000200228.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000200228

10.1590/1980-5373-mr-2020-0415

ENGINEERING, CHEMICAL

Universidade de Caxias do Sul

null

Natural Rubber Films Incorporated with Red Propolis and Silver Nanoparticles Aimed for Occlusive Dressing Application

Garcia, Charlene Silvestrin Celi

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract In this work, NRL films were enriched with red propolis and silver nanoparticles with the aim of obtaining dressings with bactericide properties. To improve the properties of these materials, plasma treatment was also applied to the films. Cytotoxic effects were evaluated by MTT and agar diffusion assays on secondary and stem cells. Determination of cell behavior on the films were assessed by EDS and FEG-SEM. In general, the plasma modified NRL films presented hydrophilic character, favorable condition for biomedical applications. RBS results showed that silver is probably in nanoparticulate form. MTT assays revealed that non-cytotoxic effects were observed for all the samples extracts. Either the plasma treatment or silver deposition were effective in sterilizing the samples and modifying their surfaces. It was demonstrated in this in vitro study that ADSCs associated with NRL films enriched with propolis should be considered promising for application in the healing of occlusive wounds.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000200228&lng=en&tlng=en

91

scielo_articles/scl/1516-1439/S1516-14392021000200228.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Garcia, Charlene Silvestrin Celi", "Maddalozzo, Ana Elisa Dotta", "Garcia, Paulo Miguel Celi", "Fontoura, Cristian Padilha", "Rodrigues, Melissa Machado", "Giovanela, Marcelo", "Henriques, João Antonio Pêgas", "Aguzzoli, Cesar", "Silva Crespo, Janaina da", "Roesch-Ely, Mariana" ]

null

[ "natural rubber latex films", "plasma treatment", "wound dressing", "red propolis", "silver nanoparticles" ]

null

[ "Universidade de Caxias do Sul", "Universidade de Caxias do Sul", "Sociedade Brasileira de Cirurgia Plástica" ]

scl/1516-1439/S1516-14392021000200209.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000200209

10.1590/1980-5373-mr-2020-0329

ENGINEERING, CHEMICAL

Universidade Federal do ABC

null

Investigation and Nanomechanical Behavior of the Microconstituents of Al-Si-Cu alloy After Solution and Ageing Heat Treatments

Santos, Silvano Leal dos

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The effects of heat treatment on the microstructural evolution and mechanical behavior of Al-Si-Cu alloy were investigated. Solution heat treatment was performed at 500oC/6h and 540oC/6h, followed by quenching in warm water at 60ºC. Lastly, artificial ageing treatment was performed at 160ºC/6h, 190ºC/4h and 210ºC/2h. The microstructural evolution of the samples before and after heat treatments was analyzed by optical microscopy, scanning electronic microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). Analyses revealed the presence Al5FeSi, Al15(FeMn)3Si2, Al2Cu and Si particles. The morphologies of the present phases were dependent on the heat treatment. Solution treatment at 540ºC/6h resulted in significant softening of the alloy compared with the treated samples at 500ºC/6h. Vickers hardness analysis indicated that the hardness peak of the alloy after heat treatment was about 125 HV. Mechanical properties of different phases have been investigated by nanoindentation technique, which indicated that the highest hardness and modulus of elasticity were found for the Si particle, especially those distributed in the microstructures of the samples submitted to higher solution and ageing temperatures.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000200209&lng=en&tlng=en

52

scielo_articles/scl/1516-1439/S1516-14392021000200209.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Santos, Silvano Leal dos", "Toloczko, Felipe Ribeiro", "Merij, Abrão Chiaranda", "Saito, Newton Haruo", "Silva, Davinson Mariano da" ]

null

[ "Aluminum alloys", "Intermetallic compounds", "Heat treatments", "Nanoindentation" ]

null

[ "Universidade Federal do ABC", "Faculdade de Tecnologia de São Paulo", "Faculdade de Tecnologia de São Paulo" ]

scl/1516-1439/S1516-14392021000200207.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000200207

10.1590/1980-5373-mr-2020-0323

ENGINEERING, CHEMICAL

Manipal Academy of Higher Education

null

Two Body Wear Characteristics of Polyalthia Longifolia/Mangifera Indica/Jute Fiber Reinforced Epoxy Composites using Taguchi Technique

Heckadka, Srinivas Shenoy

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract This research work investigates the two body wear behavior of natural fiber reinforced composites using a pin on disc test set-up. Natural fibers such as Polyalthia Longifolia, Mangifera Indica and Jute were used as reinforcements with epoxy matrix. Four types of composites with 30% fiber weight fraction were fabricated using hand layup and compression molding technique. Taguchi experimental design with L16 orthogonal array was considered. Four factors viz. fiber type, normal load, sliding speed and sliding distance at four levels were analyzed for obtaining minimum specific wear rate. Normal load was the most significant factor influencing the response with percentage contribution of 56.21% while the least contribution was the factor sliding speed (2.30%). Based on the optimum combination, confirmation experiments were conducted, the results of which were obtained with a minimal error of 4.64%. Micrographs revealed different wear mechanisms like fiber-matrix de-bonding, fiber pull-out, matrix cracking, furrows and crater formation.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000200207&lng=en&tlng=en

49

scielo_articles/scl/1516-1439/S1516-14392021000200207.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Heckadka, Srinivas Shenoy", "Nayak, Suhas Yeshwant", "Rao, Sathish", "Samant, Rashmi", "L. K, Shrinidhi", "Salunkhe, Krishna Manoj" ]

null

[ "Polyalthia Longifolia", "Mangifera Indica", "Jute", "Epoxy", "Taguchi", "Sliding wear", "Scanning Electron Microscopy" ]

null

[ "Manipal Academy of Higher Education" ]

scl/1516-1439/S1516-14392020000600223.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392020000600223

10.1590/1980-5373-mr-2020-0268

ENGINEERING, CHEMICAL

University College of Engineering Dindigul

null

Determination of Wear, Friction Behavior and Characterization of Carbon Fiber Reinforced Epoxy Composites for Transport Applications

Sudhagar, S.

2,020

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Thermoplastics are finding the place in the current industrial sector due to its load bearing capacities. In this research, With the aid of pin on disc test set up, adhesive and abrasive wear behavior of leaf spring materials 30% short carbon fiber reinforced epoxy (SF), 30% long carbon fiber reinforced epoxy (LF) as well as Unreinforced epoxy (UF) are evaluated for automobile applications. Under multi pass abrasive wear condition, the effect of fiber reinforcement on plastic energy of deformation, matrix crystallinity and clogging behavior were investigated. The transient friction of Leaf spring materials was carried out under the load condition of 19.62N and 28.43N. During the friction test, the effect of fiber length, fiber loading condition on the co-efficient of friction and its specific wear rate of the composite materials are also investigated. The increase in load during adhesive mode for all the materials, specific wear rate and wear volume of the test materials also increased. Furthermore, the fiber- matrix interface, fractured surfaces were observed thoroughly through Scanning Electron microscopic (SEM) morphology.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392020000600223&lng=en&tlng=en

24

scielo_articles/scl/1516-1439/S1516-14392020000600223.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Sudhagar, S.", "Kumar, S. Sathees" ]

null

[ "Carbon fiber", "Short carbon fiber", "Long carbon fiber", "Transient friction", "Wear", "SEM" ]

null

[ "University College of Engineering Dindigul", "CMR Institute of Technology" ]

scl/1516-1439/S1516-14392021000100204.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100204

10.1590/1980-5373-mr-2020-0233

ENGINEERING, CHEMICAL

Lanzhou City University

null

The role of ERNi-1 wire on Microstructure and Properties of Pure Nickel N6 Plasma Arc Welding joint

Chai, Ting Xing

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The butt welding tests of 5.5mm thick pure nickel N6 plate were carried out by plasma arc welding (PAW) and ERNi-1wire-filled PAW. And the differences in microstructure and properties between two kinds of joints were studied. The results show that the wire-filled pure nickel N6 joint has good appearance without defects such as pores, cracks, and undercuts. Pure nickel N6 weld is single-phase austenite structure, and no phase transformation occurs during heating or cooling. The weld zone of PAW joint is characterized by coarse columnar grain with average grain size of 125.8 μm, while the weld zone of wire-filled joint is equiaxed grain with average grain size of 54.8 μm. The tensile strength of the wire-filled PAW joint is 337MPa and the elongation after fracture is 44%, which is 11.6% and 85.5% higher than that of the PAW joint. The corrosion rate of wire-filled PAW joint is 2.6908g/m2h, which is lower than that of PAW joint of2.8820g/m2h, and the corrosion rates of both joint are higher than the base metal. The alloy elements in the welding wire can supplement the alloy elements burned in the welding process. As the filler metal, the melted wire forms the joint with the melted base metal, avoiding the defects such as undercut and depression. Al and Ti elements in ERNi-1 wire have deoxidation and nitrogen fixation effect during welding thermal cycle process, which improves the resistance of weld to carbon monoxide and nitrogen porosity. In the process of nitrogen fixation, TiN particles are formed in the crystal or grain boundary. TiN particles at the grain becomes heterogeneous nucleation particles in the grain, which makes a large number of nucleation and increases the nucleation rate. TiN particles at grain boundaries act as "nails" to hinder the migration of austenite grain boundaries. In the deoxidization process, the deoxidized products Al2O3 and TiO2 are formed. However, large-size inclusions are formed owing to the high content of Al and Ti in the molten pool, which affects the performance of the joint. Therefore, the structure and performance of filler wire-filled PAW joint are better than those of PAW joint.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100204&lng=en&tlng=en

48

scielo_articles/scl/1516-1439/S1516-14392021000100204.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Chai, Ting Xing", "Zhang, Liang Liang", "Wang, Xi Jing", "Xu, Hong Tong" ]

null

[ ": Pure nickel N6", "Plasma arc welding", "Corrosion Resistance" ]

null

[ "Lanzhou City University", "Lanzhou University of Technology" ]

scl/1516-1439/S1516-14392021000100210.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100210

10.1590/19020-080-5373-mr-2020-0267

ENGINEERING, CHEMICAL

Universidade Federal do Piauí

null

Influence of Hastelloy’s Cathodic Cage Plasma Deposition on Corrosion Resistance of AISI 304 Stainless Steel and of AISI D6 Tool Steel

Costa, Pablo Matheus Oliveira

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract AISI D6 tool steel and AISI 304 stainless steel are among the most widely used material in the industry. However, this application field can still be expanded through the coatings deposition. In this regard, the objective of this work was to evaluate the impact of coatings application by cathodic cage technique using Hastelloy’s cathodic cage, on corrosion resistance of these steels. Two treatment temperatures were compared. The samples were characterized by Optical Microscopy, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, X-Ray Diffraction with the application of the Rietveld routine and corrosion test. The results showed the formation of multiphase layers that contributed to corrosion potentials reduction for treatments at 400 °C, being more effective when applied on AISI D6. It was observed that the corrosion resistance is influenced by the temperature, which was attributed to the precipitation of chromium nitride and iron oxide at 450 ºC.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100210&lng=en&tlng=en

60

scielo_articles/scl/1516-1439/S1516-14392021000100210.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Costa, Pablo Matheus Oliveira", "Serra, Petteson Linniker Carvalho", "Monção, Renan Matos", "Menezes, Alan Silva de", "Borges, Ferdinando Marco Rodrigues", "Costa, Thercio Henrique de Carvalho", "Sousa, Rômulo Ribeiro Magalhães de" ]

null

[ "Cathodic cage", "Hastelloy", "corrosion resistance", "AISI D6", "AISI 304" ]

null

[ "Universidade Federal do Piauí", "Universidade Federal do Piauí", "Universidade Federal do Maranhão", "Instituto Federal do Maranhão", "Universidade Federal do Rio Grande do Norte" ]

scl/1516-1439/S1516-14392021000100209.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100209

10.1590/1980-5373-mr-2020-0250

ENGINEERING, CHEMICAL

Udon Thani Rajabhat University

null

Structures and Properties of KxCryNi1-x-yO Dielectric Materials Prepared by an Ultrasonic-Assisted Sol-Gel Method

Khumpaitool, Bualan

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract KxCryNi1-x-yO (x = 0.05-0.20, y = 0.02) dielectric materials were prepared using a facile simple green ultrasonic-assisted sol-gel method. All samples have a main phase consisting of a cubic NiO structure and with nanoscale crystallite sizes (28.58-37.51 nm). However, secondary phases were also observed for the samples with x values exceeding 0.10. The fractured surface microstructures of the samples with x values less than 0.15 exhibited uniformly distributed spherical grains. Other samples showed irregularly shaped grains. The grain sizes were larger when x was increased to 0.15 and exhibited increased grain growth probably due to substitution of K ions into the NiO lattice. However, a reduction of grain sizes was observed in the sample with x = 0.20, possibly due to inhibition of the grain growth by the secondary phase. At room temperature and a frequency of 1013 Hz, the highest dielectric constant of 2.25 × 104 was obtained for the samples with x = 0.15.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100209&lng=en&tlng=en

50

scielo_articles/scl/1516-1439/S1516-14392021000100209.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Khumpaitool, Bualan", "Utara, Songkot", "Khemprasit, Jinda", "Youngme, Sujittra" ]

null

[ "Ceramics", "NiO", "Sol-gel process", "Dielectric property", "Ultrasonic" ]

null

[ "Udon Thani Rajabhat University", "Udon Thani Rajabhat University", "Khon Kaen University" ]

scl/1516-1439/S1516-14392021000100208.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100208

10.1590/1980-5373-mr-2020-04047

ENGINEERING, CHEMICAL

Instituto Federal de Educação Ciência e Tecnologia do Rio Grande do Sul

null

New ASPN High Efficiency Treatment of ASTM M2 Steel

Lima, Edison Silva

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Plasma nitriding treatments are applied to achieve excellent surface properties on steel parts and tools. Active screen plasma nitriding (ASPN) does not have the defects presents in direct nitriding plasma treatments (DCPN). However, ASPN require much longer processing times to develop surface layers as deep as those of DCPN. This work presents the development of a biased ASPN treatment system, to investigate the possibility of achieving greater efficiency. The treatments were performed on ASTM M2 steel samples using the same processing parameters in 4 different configurations: DCPN, ASPN and 2 active screen plasma nitriding with biased specimens voltage: one was called "bright bias", because biased voltage is high enough to develop a plasma glow on the samples, and the other "dark bias", where no plasma glow sheath is seen on the samples. The active screen dark biased treatment presented the best results. These results could be understood by the electromagnetic field generated by the bias source promoting the deposition of nitrogen ions on the surface of the part being treated. Therefore, it was demonstrated that the use of dark bias voltage in the active screen treatment in larger reactors is fundamental to achieve good nitriding results in smaller times.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100208&lng=en&tlng=en

12

scielo_articles/scl/1516-1439/S1516-14392021000100208.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Lima, Edison Silva", "Oliveira, Leonardo Fonseca", "Rocha, Alexandre da Silva" ]

null

[ "Plasma nitriding", "active screen", "ASTM M2", "surface treatment", "bias voltage" ]

null

[ "Instituto Federal de Educação Ciência e Tecnologia do Rio Grande do Sul", "Universidade Federal do Rio Grande do Sul", "Universidade Federal do Rio Grande do Sul" ]

scl/1516-1439/S1516-14392021000100207.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100207

10.1590/1980-5373-mr-2020-0346

ENGINEERING, CHEMICAL

Universidade Federal do Rio Grande do Sul

null

Effect of Compressive Deformations on the Final Microstructure of a Low Carbon High Silicon Bainitic Steel Thermomechanically Processed

Hatwig, Rodrigo Afonso

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Due to a combination of advantages, high-performance steel components, especially for automotive manufacturing applications, are generally forged parts. In the forging industry, bainitic steels are being increasingly used, because they can reduce the processing chain and energy consumption. In this case, the bainitic microstructure can be obtained immediately after forging, with controlled cooling, and without any subsequent heat treatment. In the present work, the effect of thermomechanical routes performed in the austenitic and bainitic fields on the final microstructure and final hardness of 18MnCrSiMo6-4 bainitic steel has been discussed. Thermomechanical processing routes were tested and evaluated in a Gleeble® 3800 testing machine with one and two-step deformation. In both cases, the sample had its height reduced by 40% and the strain rate used was 0.1s-1. It could be shown that the plastic deformation promoted in the bainite field induces the bainite transformation. The results also show a strong dependence of bainite morphology concerning the deformation temperature of the steel. Moreover, the knowledge of the hot and warm stress-strain curves is an important result because it allows estimating the necessary stress and the energy consumption per volume unit to deform the material.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100207&lng=en&tlng=en

23

scielo_articles/scl/1516-1439/S1516-14392021000100207.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Hatwig, Rodrigo Afonso", "Dong, Juan", "Epp, Jérémy", "Rocha, Alexandre da Silva" ]

null

[ "thermomechanical treatment", "energy saving", "bainitic steel" ]

null

[ "Universidade Federal do Rio Grande do Sul", "Universität Bremen" ]

scl/1516-1439/S1516-14392021000100206.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100206

10.1590/1980-5373-mr-2020-0315

ENGINEERING, CHEMICAL

Universidade Federal de Sergipe

null

Structure, mechanical properties and oxidation resistance of iso and non-iso architected TiN/Cr multilayers coatings deposited by magnetron sputtering

Soares, Vagner F. G.

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Iso and non-iso architected TiN/Cr multilayers with constant composition were deposited by balanced magnetron sputtering aiming to investigate the influence of different architectures over coatings structures and properties. Glow discharge optical emission spectroscopy analyses were used to determine in-depth constituents and suggested that no diffusion of elements occurred between layers in room temperature. Field emission gun scanning electron microscopy analyses showed that all multilayers presented sharp interfaces and low porosity microstructures, with column-like grain growth influenced by layer sizes. Glancing angle X-ray diffraction analyses showed that multilayers consist of polycrystalline α-Cr and δ-TiN phases with a main peak in Cr(110) plane. The overlapping of TiN onto metallic layers led to the suppression of growth in the TiN(111) plane, although TiN layers thicker than 50 nm demonstrated a growth in plane TiN(200). Nanoindentation tests registered equal hardness values for all multilayers of around 16.2 GPa, on the other hand, a tendency to improve hardness has been identified for hierarchical multilayer. Oxidation tests revealed that architectures with thicker TiN top layers presented an improved oxidation resistance up to 600 ºC, probably due to growth in more compact TiN(200) plane. However, TiN/Cr coatings did not resist integrally to oxidation tests at 750 ºC.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100206&lng=en&tlng=en

32

scielo_articles/scl/1516-1439/S1516-14392021000100206.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Soares, Vagner F. G.", "Ramirez, Daniel A.", "Damasceno, Igor Z.", "Echevirrigaray, Fernando G.", "Figueroa, Carlos A.", "Perotti, Bruna L.", "Serafini, Francisco L.", "Oliveira, Givanilson B.", "Terto, André R.", "Tentardini, Eduardo K." ]

null

[ "Coatings", "magnetron sputtering", "TiN/Cr multilayers", "non-iso architectures", "high temperature oxidation" ]

null

[ "Universidade Federal de Sergipe", "Universidade Federal do Rio Grande do Norte", "Universidade Estadual de Campinas", "Universidade de Caxias do Sul" ]

scl/1516-1439/S1516-14392021000100205.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100205

10.1590/1980-5373-mr-2020-0300

ENGINEERING, CHEMICAL

State University of Malang

null

Effects of Various Sintering Conditions on the Structural and Magnetic Properties of Zinc Ferrite (ZnFe2O4)

Puspitasari, Poppy

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Zinc ferrite (ZnFe2O4) nanoparticles have attracted the attention of researchers because of their unique chemical properties and particle-size-dependent magnetic properties. High-surface-area spinel ferrites have numerous technical applications in areas such as high-density information storage, ferrofluids, and catalysis. The coprecipitation technique is the preferred method for preparing nanoscale ZnFe2O4 because it results in a small crystals with a uniform size distribution. In this study, the synthesis was conducted in solution for 48 h, followed by sintering at 1000°C for 1.5–3.5 h. The smallest crystals (70.58 nm) were found in the sample sintered for 2.5 h. Fourier transform infrared spectroscopy (FTIR) functional-group analysis confirmed the presence of Fe–O and Zn–O bonds of cations in octahedral and tetrahedral sites. The ZnFe2O4 sintered for 3.5 h was superparamagnetic. The characterization results suggest that the obtained ZnFe2O4 could be used as a nanofluid in heat exchangers.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100205&lng=en&tlng=en

31

scielo_articles/scl/1516-1439/S1516-14392021000100205.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Puspitasari, Poppy", "Rizkia, Ufsarah Anugrah", "Sukarni, Sukarni", "Permanasari, Avita Ayu", "Taufiq, Ahmad", "Putra, Andika Bagus Nur Rahma" ]

null

[ "Ferrite", "Coprecipitation", "Hysteresis", "Sintering" ]

null

[ "State University of Malang", "State University of Malang", "State University of Malang" ]

scl/1516-1439/S1516-14392021000100203.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100203

10.1590/1980-5373-mr-2020-0350

ENGINEERING, CHEMICAL

Dalian Maritime University

null

Preparation of Metal-Incorporated SAPO-34 catalysts and their Catalytic Performance in Selective Catalytic Reduction of Nitric Oxide

Wang, Dapeng

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Metal-incorporated SAPO-34 catalysts were prepared by one-step hydrothermal method. Effects of various parameters including the types of metal ions, Cu2+ sources, structure directing agents (SDAs), hydrothermal temperature and time on catalyst activity of the metal-incorporated SAPO-34 catalysts were investigated. Three types of metal-incorporated SAPO-34 catalysts (Cu/SAPO-34, Fe/SAPO-34 and Mn/SAPO-34) were successfully obtained. Compared with Fe/SAPO-34 and Mn/SAPO-34 catalysts, Cu/SAPO-34 catalyst revealed complete cubic-like microstructure, wide active temperature window and high conversion rate in selective catalytic reduction (SCR) of nitric oxide. After defined Cu2+ was the favorable active site of SAPO-34 catalyst, the effects of four Cu2+ sources on SCR performance were further investigated, and found Cu2+ sources did not produce significant influence on nitric oxide conversion rates. SDAs determined the formation of Cu/SAPO-34 catalyst, and the Cu/SAPO-34 catalyst adopting tetraethylenepentamine (TEPA) as SDA could maintain higher crystal integrity and active sites, which were in favor of the SCR reaction. Moreover, hydrothermal temperature and time had great influences on the formation of Cu/SAPO-34 catalyst. When the hydrothermal temperature was higher than 150 oC and the hydrothermal time was longer than 3 days, the Cu/SAPO-34 catalyst with a cubic-like structure and high catalyst activity could be obtained.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100203&lng=en&tlng=en

41

scielo_articles/scl/1516-1439/S1516-14392021000100203.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Wang, Dapeng", "Yang, Yi", "Song, Chengwen" ]

null

[ "Selective catalytic reduction", "Cu/SAPO-34", "catalyst activity", "nitric oxide" ]

null

[ "Dalian Maritime University", "Dalian Maritime University" ]

scl/1516-1439/S1516-14392021000100212.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100212

10.1590/1980-5373-mr-2020-0243

ENGINEERING, CHEMICAL

Universidade Estadual Paulista

null

Calcium Silicate-Based Experimental Sealers: Physicochemical Properties Evaluation

Zordan-Bronzel, Cristiane Lopes

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The aim of this study was to evaluate physicochemical properties of calcium silicate-based experimental (CS) endodontic sealers, developed using two different vehicles: polyethylene glycol (PG) (CS-PG) or polyethylene glycol associated to chitosan hydrogel (CS-PGCH). TotalFill BC Sealer (TF) and AH Plus (AHP) were evaluated for comparison. Setting time, flow, radiopacity, pH, solubility and volumetric change were analyzed. Data were submitted to ANOVA and Tukey tests with 5% significance level. The CS-PGCH had significantly greater setting time. CS-PG flow was similar to AHP. CS-PG had higher radiopacity than CS-PGCH. Calcium silicate-based sealers presented alkaline pH in all periods. CS-PGCH presented higher solubility in comparison with CS-PG. The volumetric change of CS-PG was similar to TF after 7 days, and to AHP after 30 days. CS-PG presented proper setting time, radiopacity, flow and pH, besides low volumetric change, showing better results than CS-PGCH, and potential for clinical application.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100212&lng=en&tlng=en

44

scielo_articles/scl/1516-1439/S1516-14392021000100212.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Zordan-Bronzel, Cristiane Lopes", "Tanomaru-Filho, Mario", "Chávez-Andrade, Gisselle Moraima", "Torres, Fernanda Ferrari Esteves", "Abi-Rached, Giselle Priscilla Cruz", "Guerreiro-Tanomaru, Juliane Maria" ]

null

[ ": Biocompatible Materials", "Calcium Silicate", "X-Ray Microtomography", "Dental Materials", "Physical Properties" ]

null

[ "Universidade Estadual Paulista" ]

scl/1516-1439/S1516-14392021000100202.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100202

10.1590/1980-5373-mr-2020-0321

ENGINEERING, CHEMICAL

Vietnam National University–Ho Chi Minh City

null

Poly(L-glutamic acid) via catalytical hydrogenation for the fabrication of carbon nanotube nanocomposites

Nguyen, Luan Thanh

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The synthesis of poly(L-glutamic acid) (PG) was investigated. Reduction of poly(benzyl-L-glutamate) by the palladium/charcoal catalyst proved to be an effective method for obtaining polyglutamic acid pure and particularly exhibiting in the α-helix secondary structure. The structure of this synthetic polypeptide was assessed by infrared spectroscopy, gel permeation chromatography, proton nuclear magnetic resonance spectroscopy, temperature-modulated differential scanning calorimetry and wide-angle powder X-ray diffraction methods. The α-helical PG was, for the first time, combined with multi-walled carbon nanotubes (MWCNTs). The obtained PG was demonstrated to be a promising matrix to disperse MWCNTs, forming MWCNT/PG biocomposites.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100202&lng=en&tlng=en

48

scielo_articles/scl/1516-1439/S1516-14392021000100202.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Nguyen, Luan Thanh", "Le Tran, Hai", "Mai, Phong Thanh", "Duong, Vu Ba", "Nguyen, Le-Thu T.", "Nguyen, Ha Tran" ]

null

[ "Poly(L-glutamic acid)", "nanocomposites", "multi-walled carbon nanotubes" ]

null

[ "Vietnam National University–Ho Chi Minh City", "Vietnam National University–Ho Chi Minh City", "Ho Chi Minh City University of Education", "Vietnam National University–Ho Chi Minh City" ]

scl/1516-1439/S1516-14392021000100201.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100201

10.1590/1980-5373-mr-2020-0235

ENGINEERING, CHEMICAL

Universidade Federal do Rio de Janeiro

null

Application of an Aqueous Extract of Cotton Seed as a Corrosion Inhibitor for Mild Steel in HCl Media

Hernandes, Isabel da Silva

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The present work aims to study the aqueous cotton seeds extract as a natural inhibitor of the corrosion of mild steel in 1 mol L−1 HCl using gravimetric tests, potentiodynamic polarization curves, electrochemical impedance measurements and surface morphological analysis by scanning electron microscopy (SEM). The aqueous cotton seed extract acted as a good corrosion inhibitor reaching an inhibition efficiency of 95.7% after 24 h of immersion for 800 mg L−1 inhibitor concentration. For the gravimetric tests varying the temperature, a decrease of the activation energy (Ea) was observed, suggesting a chemical adsorption on the surface of the metal. 400 mg L−1 of the high molecular weight fraction isolated from the total extract showed inhibition efficiency equal to 800 mg L−1 of the total extract, 97.3% and 94.2% from electrochemical impedance and polarization curves data, respectively, suggesting that the macromolecules present a fundamental participation in the inhibitive process.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100201&lng=en&tlng=en

41

scielo_articles/scl/1516-1439/S1516-14392021000100201.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Hernandes, Isabel da Silva", "Cunha, Jéssica Nogueira da", "Santana, Carolina Araujo", "Aquino Rodrigues, José Guilherme", "D’Elia, Eliane" ]

null

[ "Mild steel", "corrosion inhibitor", "cotton seed", "natural products" ]

null

[ "Universidade Federal do Rio de Janeiro" ]

scl/1516-1439/S1516-14392020000600227.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392020000600227

10.1590/1980-5373-mr-2020-0309

ENGINEERING, CHEMICAL

Universidade Federal de São Carlos

null

Microstructure Features and Mechanical Properties of Double-Sided Friction Stir Welded Joints of AA2050-T84 Thick Plates

Santini, F. F.

2,020

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract As part of an ongoing process to fully assess the potential for friction stir welding (FSW) to be used in the aerospace industry, an attempt was made to produce double sided FSW joints at traverse speeds equal or higher than 5 mm/s of AA2050-T84 12.7 mm thick plates for high-volume production applications. With an emphasis on weld quality, the local and global mechanical properties were evaluated and correlated with microstructure of the welding area. Sound welds with no volumetric defects were obtained for tool traverse speeds up to 12 mm/s, resulting in yield and ultimate tensile strengths corresponding to 65% and 77% of base material, respectively. The metallurgical and mechanical characterization demonstrate that density of Cu-rich precipitates has a first order effect on micro-hardness variation. In the stir zone the dissolution temperature of this precipitate is achieved and its volume fraction is greatly reduced. The remaining precipitates seems to be partially dissolved and undergone a significant thickening at the welding zones in which the process temperature has not reached the dissolution temperature. Weld fractures after tensile tests were observed to start in the region of hardness minima.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392020000600227&lng=en&tlng=en

16

scielo_articles/scl/1516-1439/S1516-14392020000600227.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Santini, F. F.", "Plaine, A. H.", "Afonso, C. R. M.", "Bergmann, L.", "de Alcântara, N. G.", "dos Santos, J. F.", "Miyazaki, M. H." ]

null

[ "DS-FSW", "Friction Stir Welding", "high-speed welding", "aluminum-cooper-lithium alloys", "mechanical performance" ]

null

[ "Universidade Federal de São Carlos", "Universidade do Estado de Santa Catarina", "elmholtz-Zentrum Geesthacht", "Embraer S.A" ]

scl/1516-1439/S1516-14392020000600226.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392020000600226

10.1590/1980-5373-mr-2020-0494

ENGINEERING, CHEMICAL

Universidade Estadual do Norte Fluminense

null

Failure Prediction of AISI 420 Martensitic Stainless Steel Using the Theory of Critical Distances

Siqueira, Marcelo de Oliveira

2,020

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

This work aims to evaluate the capability of the theory of critical distances (TCD) to predict the static failure of U-notched AISI 420 martensitic stainless steel specimens with different geometric features under pure bending loading. Theoretical estimates of the stress intensity factor during fracture onset were calculated according to the line (LM) and point methods (PM), which consider the characteristic length L, inherent strength σ0, and notch tip radius ρ. Initially, L and σ0 were determined on the basis of the material’s properties (i.e., fracture toughness KIc and ultimate tensile strength σu,t), resulting in imprecise estimates. Conversely, L and σ0 determined using the appropriate analysis of linear–elastic stress fields ahead of notches with different sharpness provided highly accurate predictions. The microscopic study of fractured specimens ensured better comprehension of the results. Moreover, the accurate values of L and σ0 were used to predict the failure of V-notched specimens.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392020000600226&lng=en&tlng=en

32

scielo_articles/scl/1516-1439/S1516-14392020000600226.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Siqueira, Marcelo de Oliveira", "Carvalho, Eduardo Atem de" ]

null

[ "Theory of critical distances", "AISI 420", "U-notch", "V-notch", "Small-scale yielding" ]

null

[ "Universidade Estadual do Norte Fluminense" ]

scl/1516-1439/S1516-14392020000600225.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392020000600225

10.1590/1980-5373-mr-2019-0631

ENGINEERING, CHEMICAL

Nanjing Institute of Technology

null

Microstructure and Corrosion Behavior of Ni-Cr-Mo Nickel-based Alloy Weld

Chu, Yajie

2,020

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract The mechanical properties and corrosion performance of the N10276 alloy welded joint were investigated with nano-hardness testing and electrochemical measurement. The results showed that solidification mode changes from equiaxed crystal to columnar crystal from the center of the weldment to the fusion zone. With the increase of immersion times, the diameter of capacitance arc and the impedance modulus increase, and the corrosion resistance of HAZ decreases. The strengthening effect of welded metal was more obvious than that of heat affected zone for the nickel-based welded joint and especially in coarse grained heat affected zone, the hardening resulted from overheating was not apparent. Nickel-based weld metal with high content of alloying elements were often segregated at interdendritic regions or precipitated in grain interior under nonequilibrium solidification, which differ from conventional low alloy steel welded joint.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392020000600225&lng=en&tlng=en

31

scielo_articles/scl/1516-1439/S1516-14392020000600225.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Chu, Yajie", "Chen, Yuan", "Chen, Yixin", "Liu, Peng", "Li, Xiaoquan" ]

null

[ "Nickel-base alloy", "Nanoindentation", "Corrosion behavior", "Electrochemical properties" ]

null

[ "Nanjing Institute of Technology", "Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology", "Shandong Jianzhu University" ]

scl/1516-1439/S1516-14392021000100211.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392021000100211

10.1590/1980-5373-mr-2020-0366

ENGINEERING, CHEMICAL

Universidad Pedagógica y Tecnológica de Colombia

null

Synthesis of the La3Ba5Cu8O18-δ and Sm3Ba5Cu8O18-δ superconductors by the combustion and solid-state reaction methods

Guerrero, U. Fuentes

2,021

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract In this paper, the synthesis of the La3Ba5Cu8O18-δ and Sm3Ba5Cu8O18-δ superconductors using the combustion method is reported for the first time. Besides, a comparison with the solid-state reaction method was performed. The materials were synthesized at 870 °C for 24 h under oxygen flow. Rietveld refinement showed materials with the main crystal phase corresponding to the orthorhombic structure of space-group Pmm2 (25), with purity in the range 51-85%, which had not reported for the RE358 systems. On the other hand, the magnetic measurements under external fields (30 and 100 Oe) confirmed the diamagnetic response associated with the Meissner effect, and Tc values between 24 and 58 K.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392021000100211&lng=en&tlng=en

28

scielo_articles/scl/1516-1439/S1516-14392021000100211.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Guerrero, U. Fuentes", "Rivera, A.M. Morales", "Cuaspud, J.A. Gómez", "Munevar, J.", "Vargas, C.A. Parra" ]

null

[ "Superconductor", "combustion", "solid-state reaction" ]

null

[ "Universidad Pedagógica y Tecnológica de Colombia", "Universidade Federal do ABC (UFABC)" ]

scl/1516-1439/S1516-14392023000100219.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392023000100219

10.1590/1980-5373-mr-2022-0330

ENGINEERING, CHEMICAL

University of Latvia

null

Directional Solidification of Aluminum A360 under Moderate DC Magnetic Field and Electric Current

Kaldre, Imants

2,023

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Metal additive manufacturing is rapidly developing technology, but its application in wider scale is limited by several factors. One of these is expensive raw material, because it requires certain physical properties. Two most popular metal additive manufacturing methods are printing from powder and printing from wire. Wire is usually produced by drawing it from rod. Rod can be produced by directional solidification, which is well known method to study the microstructure formation depending on various parameters during solidification. In this study directional solidification of A360 aluminum alloy with electromagnetic interaction is investigated. Aluminum alloy is induction melted and then directionally solidified into the rod 12-20 mm in diameter. Aim of this work is to investigate the role of axial DC magnetic field and electric current interaction on the grain refinement and mechanical properties of A360 aluminum alloy. It is found that electromagnetic interaction can be the approach to refine the grains, regulate the growth of oriented columnar grains and to improve mechanical properties of the material.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392023000100219&lng=en&tlng=en

23

scielo_articles/scl/1516-1439/S1516-14392023000100219.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Kaldre, Imants", "Bojarevičs, Andris", "Milgrāvis, Mikus", "Beinerts, Toms", "Kalvāns, Matīss" ]

null

[ "Aluminum alloys", "direct chill casting", "directional solidification", "electromagnetic processing of materials", "mechanical properties" ]

null

[ "University of Latvia" ]

scl/1516-1439/S1516-14392022000100288.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100288

10.1590/1980-5373-mr-2021-0214

ENGINEERING, CHEMICAL

Universidade Federal de São Carlos

null

Magnesium Alloys for Hydrogen Storage Processed by ECAP Followed by Low Temperature Rolling

Silva, W.B.

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

The hydrogen storage properties of pure magnesium and magnesium ZK60 alloy containing 2.5 wt% of mischmetal (Mm) processed by Cold Rolling (CR) and Low Temperature Rolling (LTR) were investigated. Before CR and LTR processing, Equal Channel Angular Pressing (ECAP) was employed in the alloys as an initial processing step to refine their microstructures. Microstructure findings showed that the ECAP+LTR route is more effective than the others to generate grain refinement - a desirable aspect in hydrogen storage materials. SEM and TEM results in combination with XPS analysis revealed that the ZK60 + 2.5 wt. % Mm alloy after being processed by ECAP + LTR had more refined grains (with sizes < 1μm) and exhibited superior resistance to the formation of oxides and/or hydroxides when compared with the pure magnesium alloy. The refined microstructures of the ECAP+LTR samples combined with the presence of highly oriented grains along to the (002) plane and large amount of defects – which are features associated to the LTR route - such as cracks and voids, resulted in a fast activation kinetics than for the samples processed by ECAP + CR route.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100288&lng=en&tlng=en

53

scielo_articles/scl/1516-1439/S1516-14392022000100288.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Silva, W.B.", "Leiva, D.R.", "Floriano, R.", "Vega, L.E.R.", "Oliveira, V.B.", "Gallego, J.", "Figueroa, S.J.A.", "Miqueles, E.X.", "Silva, E.P.", "Ishikawa, T.T.", "Botta, W.J." ]

null

[ "Mg-Alloys", "Low-Temperature rolling", "ECAP", "Hydrogen storage", "Metal hydrides" ]

null

[ "Universidade Federal de São Carlos", "Universidade Federal de São Carlos", "Universidade Estadual de Campinas", "Universidade do Estado do Rio de Janeiro", "Universidade Estadual Paulista", "Laboratório Nacional de Luz Síncrotron", "Universidade Federal dos Vales do Jequitinhonha e Mucuri" ]

scl/1516-1439/S1516-14392023000100217.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392023000100217

10.1590/1980-5373-mr-2022-0384

ENGINEERING, CHEMICAL

Universidade Federal do Paraná

null

The Influence of Pd on the Structure and Oxidation Performance of β-NiAl Diffusion Coatings

Pauletti, E.

2,023

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Aluminized coatings on Ni based alloys greatly contribute to achieve process efficiency at higher operating temperatures. The present study characterized Pd-modified and unmodified aluminized coatings and compared with those of Pt-modified coatings regarding the mechanisms of formation and oxidation performance. The results show that Pd reduces the driving force for diffusion of Al during coating formation, increases outward diffusion of Ni and reduces diffusion of alloying elements (Cr and Ti) into the intermetallic layer. In contrast, Pt increases the driving force for diffusion of Al and the mobility of Al in the intermetallic layer of the aluminized coating. These characteristics have a direct impact on oxidation at 1000 °C that showed that Pd reduced the rate of θ-Al2O3 → α-Al2O3 transformation, accounting for higher density of voids at the interface β-(NiAl)/θ-Al2O3, diffusion of oxygen into the coating, spalling and faster degradation of coatings.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392023000100217&lng=en&tlng=en

38

scielo_articles/scl/1516-1439/S1516-14392023000100217.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Pauletti, E.", "d’ Oliveira, A.S.C.M" ]

null

[ "Ni-based superalloy", "Diffusion coatings", "Aluminides", "Palladium", "Oxidation", "Al2O3" ]

null

[ "Universidade Federal do Paraná", "Universidade Federal do Paraná" ]

scl/1516-1846/S1516-18462010000100020.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100020

10.1590/S1516-18462009005000066

REHABILITATION

Universidade Federal de Santa Maria

Processamento auditivo em idosos: implicações e soluções

null

Auditory processing in elderly: implications and solutions

Buss, Leonardo Henrique

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

TEMA: processamento auditivo em idosos. OBJETIVO: estudar, através de uma revisão teórica, o processamento auditivo em idosos, as desordens que o envelhecimento auditivo causam, bem como os recursos para reduzir as defasagens nas habilidades auditivas envolvidas no processamento auditivo. CONCLUSÃO: vários são os desajustes ocasionados pela desordem do processamento auditivo em idosos. É necessária a continuidade de estudos científicos nessa área para aplicar adequadas medidas intervencionistas, a fim de garantir a reabilitação do indivíduo a tempo de minimizar os efeitos da desordem auditiva sobre o mesmo.

null

BACKGROUND: auditory processing in elderly. PURPOSE: to promote a theoretical approach on auditory processing in elderly people, the disorders caused by hearing aging, as well as the resources to minimize the auditory aging impairment of the hearing abilities involved in the auditory processing. CONCLUSION: the alterations caused by auditory processing disorder in elderly people are many. It is necessary to continue researching in this field in order to apply adequate interventionist measures, in order to assure the rehabilitation of the individual in time to minimize the effects of the hearing disorder.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100020&lng=en&tlng=en

22

scielo_articles/scl/1516-1846/S1516-18462010000100020.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Buss, Leonardo Henrique", "Graciolli, Lílian Seligman", "Rossi, Angela Garcia" ]

null

[ "Audição", "Idoso", "Percepção Auditiva", "Estimulação Acústica" ]

null

[ "Hearing", "Aged", "Auditory Perception", "Acoustic Stimulation" ]

null

[ "Universidade Federal de Santa Maria", "Universidade Federal de Santa Maria" ]

scl/1516-1846/S1516-18462010000200004.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000200004

10.1590/S1516-18462010005000029

REHABILITATION

Universidade Estadual de Campinas

O articulatório e o fonológico na clínica da linguagem: da teoria á prática

null

The articulatory and the phonological at language clinic: from theory to practice

Santana, Ana Paula

2,010

4

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: investigar como os fonoaudiólogos, na prática clínica, têm utilizado as terminologias referentes às alterações fonéticas e/ou fonológicas, assim como discutir as bases teóricas que têm fundamentado as mudanças de nomenclatura. MÉTODOS: foi realizada uma pesquisa exploratória com 60 fonoaudiólogos a fim de coletar dados por meio de respostas às perguntas: Você faz diferença entre Dislalia, Distúrbio Articulatório e Desvio Fonológico? Se sim, qual a diferença? Os dados foram analisados descritivamente através de distribuições percentuais. Foram aplicados testes de significância para a diferença de proporções, utilizando-se o nível de significância de 5%. A análise qualitativa, feita a partir de uma perspectiva discursiva, promoveu a discussão das relações entre Fonética e Fonologia e suas implicações para as alterações fonético-fonológicas. RESULTADOS: quase metade dos fonoaudiólogos entrevistados (45%) assegurou não diferenciar as terminologias utilizadas para designar as alterações fonético-fonológicas ou não saber explicá-las. Os sujeitos que afirmaram diferenciar os três termos, de forma geral, forneceram explicações evasivas ou pouco coerentes para as terminologias. Tais resultados denunciam que a maioria dos sujeitos dessa pesquisa, em suas práticas fonoaudiológicas, apenas reproduz terminologias comumente utilizadas sem um saber mais aprofundado sobre o tema, refletindo o fosso ainda existente entre a teorização linguística e a prática clínica. Esta geralmente tem sido realizada à margem daquela. CONCLUSÃO: evidencia-se, com isso, que, embora muito já se tenha construído em termos de conhecimento científico, na prática, parte dos fonoaudiólogos ainda mantém o caráter tecnicista que fez parte da história da Fonoaudiologia.

null

PURPOSE: to investigate how speech therapists have been using the terminologies that refer to phonetic/phonological disturbance in the clinical experience, as well as to discuss the theoretical basis that has supported their terminological choices. METHODS: an exploiting research was done involving sixty speech therapists in order to get data through their answers to the following questions: Do you make any difference between Dyslalia, Articulatory Impairment and Phonological Deviation? If so, what is the difference? The data were descriptively analyzed through percentage distribution. Significance tests were applied, using significance level of 5%. Data analysis that was carried through in a discursive perspective promoted the discussion on the relationship between Phonetics and Phonology and their implications on phonetic/phonological alterations. RESULTS: almost half of the interviewed speech therapists (45%) said they were not differentiating the terminologies used to name the phonetic/phonological alterations or not knowing how to explain them. The subjects that stated to differentiate the three terms, as a general rule, provided evasive or little clear explanations as for the terminologies. Such results reveal that most subjects in the said research, in their speech therapy experience, just reproduce largely used terminologies without having an appropriate know-how about the theme, reflecting the existence of a gap between the linguistic theorization and the clinical practice. The latter usually has been developed on the fringes of the former one. CONCLUSION: it was shown that, despite the great improvements in linguistic knowledge, in practice, some speech therapists still keep the thecnicist character that took part in the history of Speech Therapy.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000200004&lng=en&tlng=en

26

scielo_articles/scl/1516-1846/S1516-18462010000200004.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Santana, Ana Paula", "Machado, Maria Letícia Cautela de Almeida", "Bianchi, Kátia Simone da Rosa", "Freitas, Margareth de Souza", "Marques, Jair Mendes" ]

null

[ "Fonética", "Transtornos da Linguagem", "Diagnóstico", "Fonoterapia" ]

null

[ "Phonetics", "Language Disorders", "Diagnosis", "Speech Therapy" ]

null

[ "Universidade Estadual de Campinas", "Universidade Estadual de Campinas", "Universidade Federal do Paraná", "Universidade Federal de Mato Grosso", "Universidade do Estado do Rio de Janeiro" ]

scl/1516-1846/S1516-18462010000200003.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000200003

10.1590/S1516-18462009005000056

REHABILITATION

Prefeitura Municipal de Araraquara

Perfil das habilidades cognitivas no envelhecimento normal

null

Profile of cognitive abilities in normal aging

Souza, Valéria Lopes de

2,010

4

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: analisar as funções cognitivas em idosos no envelhecimento normal e verificar se variáveis como sexo, idade e escolaridade interferem no perfil dessas habilidades. MÉTODOS: foi realizado um estudo prospectivo, observacional transversal, com uma amostra constituída por 50 idosos institucionalizados, sem comprometimento neurológico e queixa de memória, com idade variando de 65 a 89 anos que possuíam grau de escolaridade variando de 0 a 15 anos. O teste utilizado neste estudo foi o Consortium to Establish a Registry for Alzheimer's Disease (CERAD). RESULTADOS: o sexo feminino obteve diferença significante nos subtestes de Memória, Evocação e Reconhecimento. A faixa etária de 65 - 75 anos obteve diferença significante no subteste de Evocação. A faixa de escolaridade de 8 - 15 anos obteve diferença significante nos subtestes de Boston e no de Fluência. CONCLUSÃO: as mulheres tiveram um melhor desempenho nos subtestes que envolviam memória. Os idosos considerados jovens foram melhores na prova de memória relacionada à evocação. Os indivíduos que tiveram um maior grau de instrução obtiveram um melhor desempenho nas habilidades que envolviam linguagem.

null

PURPOSE: to analyze the cognitive functions in elderly during normal aging and check if variables such as sex, age and education interfere in the profile of those abilities. METHODS: a prospective, traverse and observational study was accomplished with a sample constituted by 50 institutionalized elderly without neurological compromising and memory-related complaint, with age varying from 65 to 89 years and having an education grade varying from 0 to 15 years. The test used in this study was the Consortium to Establish a Registry for Alzheimer's Disease (CERAD). RESULTS: the feminine gender obtained significant difference in the Memory, Recall and Recognition tests. The age group: 65 - 75 years, obtained significant difference in the Recall tests. The range of education from 8 to 15 years obtained significant difference in the Boston tests and in the Fluency test. CONCLUSION: women had a better performance in the tests that involved memory. The elderly considered youths were better in the proof of memory related to recall. The individuals that had a better instruction grade obtained a better performance in the abilities that involved language.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000200003&lng=en&tlng=en

22

scielo_articles/scl/1516-1846/S1516-18462010000200003.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Souza, Valéria Lopes de", "Borges, Mirian Fernanda", "Vitória, Cássia Maria da Silva", "Chiappetta, Ana Lúcia de Magalhães Leal" ]

null

[ "Idoso", "Neuropsicologia", "Cognição" ]

null

[ "Aged", "Neuropsychology", "Cognition" ]

null

[ "Prefeitura Municipal de Araraquara", "Centro de Especialização em Fonoaudiologia Clínica", "Universidade Federal de São Paulo", "Clínica Silva Vitória", "Prefeitura Municipal de Ibaté" ]

scl/1516-1846/S1516-18462010000200002.xml

pt

editorial

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000200002

10.1590/S1516-18462010000200002

REHABILITATION

null

Fonoaudiologia, aprendizagem e educação

null

Zorzi, Jaime Luiz

2,010

4

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

null

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000200002&lng=en&tlng=en

null

scielo_articles/scl/1516-1846/S1516-18462010000200002.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Zorzi, Jaime Luiz" ]

null

scl/1516-1846/S1516-18462010000200001.xml

pt

editorial

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000200001

10.1590/S1516-18462010000200001

REHABILITATION

null

Editorial I

null

Bianchini, Esther Mandelbaum Gonçalves

2,010

4

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

null

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000200001&lng=en&tlng=en

null

scielo_articles/scl/1516-1846/S1516-18462010000200001.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Bianchini, Esther Mandelbaum Gonçalves" ]

null

scl/1516-1846/S1516-18462010000100022.xml

pt

case-report

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100022

10.1590/S1516-18462010000100022

REHABILITATION

Centro Universitário Jorge Amado

Síndrome de Sturge-Weber: relato de caso dos achados da avaliação fonoaudiológica

null

Sturge-Weber syndrome: a case report on the results of the phonoaudiological evaluation

Santos, Sara Virgínia Paiva

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

TEMA: avaliação fonoaudiológica em síndrome de rara ocorrência. PROCEDIMENTOS: descrever o desempenho apresentado na avaliação fonoaudiológica clínica de uma paciente com diagnóstico genético de Síndrome de Sturge-Weber. Para isso, utilizou-se de avaliação da motricidade e funções orofaciais, das habilidades pragmática e semântica da linguagem oral, processos perceptuais visual e auditivo, funções cognitivas e aplicação do Denver II. RESULTADOS: na avaliação da motricidade orofacial a paciente apresentou anomalias de estruturas ósseas da face, inadequação quanto à morfologia, mobilidade e tônus de todos os órgãos fonoarticulatórios, presença de reflexos de procura e sucção primitivos. Na avaliação das habilidades pragmática e semântica da linguagem oral, processos perceptuais visual e auditivo, funções cognitivas, a paciente apresentou exploração sensoriomotora, com pouca interação e atenção compartilhada e dificuldade de contato de olhos; comunicação predominantemente gestual, não havendo registros de atos comunicativos verbais. Apresentou funções comunicativas de pedido de ação, exclamativa, exploratória e protesto, e grande uso de função não focalizada. A compreensão oral mostrou-se alterada, gestos representativos esporádicos, processos perceptuais funcionais e lateralidade indefinida. No Denver II, falhou nas áreas pessoal-social, linguagem, motor fino e grosseiro. CONCLUSÃO: a paciente apresentou diagnóstico fonoaudiológico de Distúrbio de Linguagem e Disfagia Neurogênica Orofaríngea moderada sendo necessária intervenção fonoaudiológica a fim de maximizar a comunicação, bem como adequar as estruturas e funções motoras orofaciais.

null

BACKGROUND: phonoaudiological evaluation of rare occurrence syndrome. PROCEDURES: describe the performance shown in phonoaudiological clinical evaluation of a patient with genetic diagnosis of Sturge-Weber Syndrome. Evaluation of the drive and orofacial functions, semantic and pragmatic skills of oral language, perceptual visual and auditory processes, cognitive functions and test development of Denver II. RESULTS: in the assessment of orofacial drive the patient had abnormalities concerning bone structures of the face, inadequate as for the morphology, mobility and tone of all speech organs, presence of reflections of demand and sucking primitive. In the assessment of skills and Semantic Pragmatic of oral language and Speech, perceptual processes visual and auditory, cognitive functions the patient had sensoriomotor exploitation, with little interaction and shared attention of the patient and difficulty of eye contact; predominantly gestural communication, with no records of verbal communicative acts. The communicative functions of a request for action, exclamatory, exploratory and protest, and great use of non-focused light. Listening proved to be altered, representative gestures were sporadic, processes and perceptual functional laterality undefined. In the test development of Denver II, the patient failed in the areas: personal, social, language, motor fine and coarse. CONCLUSION: the patient showed speech diagnosis of phonoaudiological language and speech disturbance and moderate Oropharyngeal Neurogenic Dysphagia, being required to maximize communication, and adapt the structures and orofacial motor functions.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100022&lng=en&tlng=en

39

scielo_articles/scl/1516-1846/S1516-18462010000100022.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Santos, Sara Virgínia Paiva", "Cavalheiro, Laura Giotto" ]

null

[ "Síndrome de Sturge-Weber", "Hemangioma", "Angiomatose" ]

null

[ "Sturge-Weber Syndrome", "Hemangioma", "Angiomatosis" ]

null

[ "Centro Universitário Jorge Amado", "Centro Universitário Jorge Amado" ]

scl/1516-1846/S1516-18462010000100021.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100021

10.1590/S1516-18462009005000057

REHABILITATION

Universidade de São Paulo

Intervenção fonológica em crianças com distúrbio específico de linguagem com base em um modelo psicolinguístico

null

Phonological intervention for children with specific language impairment within a psycholinguistic model

Gahyva, Dáphine Luciana Costa

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

TEMA: intervenção fonológica em crianças com Distúrbio Específico de Linguagem, com base em um Modelo Psicolinguístico. PROCEDIMENTOS: participaram do processo de intervenção 4 pré-escolares, de ambos os gêneros, com idade entre 48 e 83 meses. O desempenho psicolinguístico dos sujeitos foi obtido em duas etapas (pré e pós-intervenção), mediante a utilização de instrumentos que avaliam diferentes níveis do processamento da informação: reconhecimento auditivo-fonético, consciência fonológica, codificação/ produção fonológica, memória de trabalho e acesso lexical. O Programa de intervenção teve duração de 4 meses. RESULTADOS: os pré-escolares apresentaram comprometimento em todos os níveis do processamento da informação avaliados (pré-intervenção), revelando que as dificuldades de organização fonológica estavam relacionadas a problemas no processamento receptivo e expressivo. Ao fim do Programa, todos apresentaram melhora no desempenho fonológico. CONCLUSÃO: o uso de procedimentos de avaliação que abordam os diferentes níveis de processamento possibilita a compreensão da natureza dos distúrbios de linguagem e permitem a programação de estratégias mais efetivas para as dificuldades de linguagem.

null

BACKGROUND: phonologic intervention for children with Specific Language Impairment, within a Psycholinguistic Model. PROCEDURES: this study involved four pre-school children, aging between 48 to 83 months, that had not been previously submitted to intervention. The psycholinguistic assessment was carried pre and post-intervention, through several instruments that evaluate diverse levels of information processing: auditory-phonetic recognition, lexical access, phonological working memory, phonological awareness, articulation, phonological production. The intervention took 4 months. RESULTS: preschool children showed difficulties in diverse evaluated processing information levels(pre-intervention), showing that the difficulties on phonological organization were related to problems in the receptive and expressive processing. To the end of the Program, all had presented improvement in the phonological performance. CONCLUSION: the use of evaluation instruments being suitable to diverse phonological processing levels propitiates the understanding on the nature of language impairments and the programming of more effective intervention strategies.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100021&lng=en&tlng=en

20

scielo_articles/scl/1516-1846/S1516-18462010000100021.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Gahyva, Dáphine Luciana Costa", "Hage, Simone Rocha de Vasconcellos" ]

null

[ "Transtornos do Desenvolvimento da Linguagem", "Testes de Linguagem", "Terapia da Linguagem" ]

null

[ "Language Development Disorders", "Language Tests", "Language Therapy" ]

null

[ "Universidade de São Paulo", "Prefeitura Municipal de Uberaba", "Universidade Estadual de Campinas", "Universidade de São Paulo" ]

scl/1516-1846/S1516-18462010000100019.xml

pt

review-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100019

10.1590/S1516-18462010000100019

REHABILITATION

Universidade Federal de Minas Gerais

Alterações auditivas e fenilcetonúria: uma revisão sistemática

null

Hearing disorders and phenylketonuria: a systematic review

Mancini, Patrícia Cotta

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

TEMA: a fenilcetonúria é uma doença genética que provoca alterações bioquímicas conduzindo a uma deficiência na síntese de proteínas e de neurotransmissores, e prejudicando o processo de mielinização. Mudanças estruturais e funcionais da mielina podem alterar os padrões de condutividade neuronal e ou diminuir a conexão sináptica em indivíduos com fenilcetonúria. Essencialmente, um tratamento dietético deve ser realizado dentro das primeiras semanas de vida para evitar as manifestações clínicas e bioquímicas da doença. Quando a dieta é mantida ininterruptamente, as crianças com fenilcetonúria apresentam desenvolvimento normal. Porém, foram observados déficits em funções executivas, na interação inter-hemisférica, na linguagem e memória mesmo em crianças com tratamento precoce e dieta adequada. Algumas pesquisas foram realizadas para investigação da relação entre fenilcetonúria e alterações auditivas. OBJETIVO: rever de forma sistemática os artigos científicos dedicados à pesquisa da relação entre alterações auditivas e hiperfenilalaninemias, destacando a fenilcetonúria clássica. As referências bibliográficas foram obtidas por meio de pesquisa nas bases de dados Lilacs, Medline, Biblioteca Cochrane e Scielo e por busca na lista de referência dos artigos identificados e selecionados. CONCLUSÃO: conclui-se que a relação entre hiperfenilalaninemias, incluindo a fenilcetonúria, e alterações auditivas ainda é controversa na literatura. Sugere-se a realização de mais investigações sobre a função auditiva nesses indivíduos a fim de elucidar essa possível relação.

null

BACKGROUND: phenylketonuria is a genetic disorder that causes biochemical alterations, leading to a deficiency in the synthesis of proteins and neurotransmitters and thereby hindering the myelination process. Structural and functional changes in myelin can alter neural conductivity patterns and or reduce synaptic connection in individuals with phenylketonuria. Essentially, a dietary treatment should be implemented in the first weeks of life in order to avoid clinical and biochemical manifestations of the disease. When diet is continually maintained, children with phenylketonuria show normal development. However, deficits in executive functions, interhemispherical interaction, language and memory have been observed even in children with early treatment and appropriate diet. Some researches were carried out for investigating the relationship between phenylketonuria and alterations in the hearing function. PURPOSE: to systematically review articles dedicated to the research of relationship between hearing disorders and hyperphenylalaninaemias, highlighting the classic phenylketonuria. The bibliographical references were obtained through research in the databases: Lilacs, Medline, Cochrane Library and Scielo and through search in the reference list of the identified and selected articles. CONCLUSION: the relationship among hyperphenylalaninaemias, including phenylketonuria, and hearing alterations is still controversial in the literature. It is suggested that more investigations as for the hearing function are necessary on those individuals in order to elucidate this possible relationship.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100019&lng=en&tlng=en

21

scielo_articles/scl/1516-1846/S1516-18462010000100019.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Mancini, Patrícia Cotta", "Starling, Ana Lúcia Pimenta", "Alves, Cláudia Fernanda Tolentino", "Martins, Thaís Maria da Mata", "Iório, Maria Cecília Martinelli" ]

null

[ "Fenilcetonúrias", "Transtornos da Audição", "Potenciais Evocados Auditivos", "Potenciais Evocados Auditivos do Tronco Encefálico" ]

null

[ "Phenylketonurias", "Hearing Disorders", "Evoked Potentials, Auditory", "Evoked Potentials, Auditory, Brain Stem" ]

null

[ "Universidade Federal de Minas Gerais", "Universidade Federal de Minas Gerais", "Universidade Federal de Minas Gerais", "Universidade Federal de São Paulo", "Universidade Federal de Minas Gerais" ]

scl/1516-1846/S1516-18462010000100012.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100012

10.1590/S1516-18462009005000052

REHABILITATION

Clínica Daniele Bernardes

Eletromiografia de superfície em pacientes portadores de paralisia facial periférica

null

Surface electromyography in peripheral facial paralysis patients

Bernardes, Daniele Fontes Ferreira

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: estudar a atividade eletromiográfica dos músculos frontal, orbicular dos olhos, zigomáticos, orbicular da boca em indivíduos normais e pacientes portadores de paralisia facial e o índice de simetria entre os dois lados da face. MÉTODOS: foram avaliados por meio da eletromiografia de superfície, seis indivíduos sem histórico de alteração na musculatura facial e seis pacientes com paralisia facial periférica. Para a avaliação eletromiográfica foram solicitados os seguintes movimentos (ao esforço máximo): elevação da testa, fechamento de olhos, protrusão labial e retração labial. RESULTADOS: encontrou-se que em indivíduos normais a média dos potenciais eletromiográficos para ambos os lados da face é semelhante, demonstrando que a integridade do nervo facial é fundamental para o equilíbrio da mímica facial. Nos pacientes com paralisia facial a média dos potenciais eletromiográficos para ambos os lados da face é significativamente diferente (evidenciando a falta de inervação neural). CONCLUSÃO: os resultados eletromiográficos mostraram diferença estatisticamente significante entres os dois lados da face nos indivíduos normais e nos pacientes com paralisia facial.

null

PURPOSE: to study the surface electromyographic activity of frontal, orbicular occuli, orbicular oris and zigomatycs muscles in normal subjects and in peripheral facial paralysis patients. METHODS: six volunteers with no facial paralysis history as well as six peripheral facial paralysis patients were evaluated with electromyography using superficial electrodes. Maximum effort muscle activity and symmetry index were measured for the voluntary movements such as: raising eyebrows, eyes closing, smiling, puckering lips. RESULTS: it was found out that in normal subjects the muscle activity values were similar between the two sides of the face, showing that the facial nerve integrity is fundamental to the balance of facial mimics. In facial paralysis patients, the mean electromyographic values for both sides of the face were significantly different (evidencing the lack of facial nerve information to the muscles). CONCLUSION: the electromyographic results showed a statistically significant difference between the two sides of the face in the normal subjects and in facial paralysis patients.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100012&lng=en&tlng=en

33

scielo_articles/scl/1516-1846/S1516-18462010000100012.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Bernardes, Daniele Fontes Ferreira", "Gomez, Maria Valéria Schmidt Goffi", "Bento, Ricardo Ferreira" ]

null

[ "Paralisia Facial", "Eletromiografia", "Nervo Facial" ]

null

[ "Facial Paralysis", "Electromyography", "Facial Nerve" ]

null

[ "Clínica Daniele Bernardes", "Universidade de São Paulo", "Universidade de São Paulo" ]

scl/1516-1846/S1516-18462010000100018.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100018

10.1590/S1516-18462010000100018

REHABILITATION

Centro de Especialização em Fonoaudiologia Clínica

Os distúrbios fonoarticulatórios na síndrome de Down e a intervenção precoce

null

The inarticulateness distress in Down syndrome and early intervention

Barata, Lívia Fernandes

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

TEMA: a criança com Síndrome de Down apresenta um atraso na aquisição e desenvolvimento dos aspectos fonoarticulatórios, atraso este, que tem sido atribuído a características físicas e ambientais que influenciam negativamente no processo de desenvolvimento. Caracterizar os aspectos fonoarticulatórios dos sujeitos com Síndrome de Down pode proporcionar uma melhor compreensão das alterações abordadas na reabilitação em suas diversas modalidades e contribuir na evolução terapêutica. Por esta razão decidiu-se focar com maior profundidade em um dos aspectos mais importantes da comunicação, a fonoarticulação. OBJETIVO: caracterizar as alterações fonoarticulatórias encontradas em indivíduos portadores da Síndrome de Down, por meio de uma revisão bibliográfica, enfocando a importância da intervenção precoce frente a tais circunstâncias. CONCLUSÃO: a falta de estimulação e o encaminhamento tardio irão interferir no desenvolvimento fonoarticulatório, assim, por meio da intervenção precoce, será possível a obtenção de melhores resultados, fazendo com que grandes problemas tornem-se alterações mínimas.

null

BACKGROUND: children with Down's Syndrome show a retard in language acquisition and develop inarticulateness distress. This delay has been attributed to the physical and environmental characteristics that have a negative impact on the development process. Characterizing articulation aspects of subjects with Down Syndrome may provide a better understanding of the changes addressed in rehabilitation in their different ways and contribute to the development therapy. For this reason, we decided to focus in greater depth in one of the most important communication aspects, the articulation. PURPOSE: characterize the inarticulateness distress found in subjects with Down Syndrome by means of a literature review, focusing on the importance of early intervention before such circumstances. CONCLUSION: lack of stimulation or late treatment will affect the development phonoarticulatory, thus, through early intervention it will be possible to obtain better results, causing major problems to become minimal disturbances.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100018&lng=en&tlng=en

24

scielo_articles/scl/1516-1846/S1516-18462010000100018.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Barata, Lívia Fernandes", "Branco, Anete" ]

null

[ "Síndrome de Down", "Distúrbios da Fala", "Diagnóstico" ]

null

[ "Down Syndrome", "Speech Disorders", "Diagnosis" ]

null

[ "Centro de Especialização em Fonoaudiologia Clínica", "Instituto de Gerenciamento em Deglutição" ]

scl/1516-1846/S1516-18462010000100017.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100017

10.1590/S1516-18462009005000063

REHABILITATION

Instituto de Reabilitação Infantil

Perfil dos pacientes atendidos no setor de fonoaudiologia de um serviço público de Recife - PE

null

Profile of patients receiving speech therapy care at a public service at Recife-PE

Barros, Percy Maria de Lima

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: traçar o perfil dos pacientes cadastrados e atendidos pelo setor de Fonoaudiologia de um serviço público de Recife. MÉTODOS: o estudo foi realizado a partir da coleta e análise dos dados referentes à origem do encaminhamento, faixa etária, gênero, queixas fonoaudiológicas de crianças, adolescentes, adultos e idosos, colhidos das fichas das entrevistas iniciais. A amostra foi constituída por todos os indivíduos cadastrados no setor de Fonoaudiologia de um serviço público da cidade de Recife, no período de julho de 2007 a maio de 2008. RESULTADOS: dos 251 pacientes atendidos, 12 foram excluídos da pesquisa, três destes obtiveram alta fonoaudiológica e nove não apresentavam os dados completos. Das fichas analisadas, houve um maior número de encaminhamento realizado por Pediatras (25%), em seguida Otorrinolaringologista (16%) e Clínico Geral (10%), sendo a maioria do sexo masculino (61%), com idade entre 0 a 11 anos de idade. De acordo com as queixas, as mais freqüentes foram de desvio fonológico (14%), seguidos de atraso de linguagem (11%), disfluência (10%) e respirador oral (8%). Em relação ao número de queixas apresentadas, 72% apresentaram uma queixa, 25% duas queixas e 2 % três queixas associadas. CONCLUSÕES: o perfil atendido no setor de fonoaudiologia de um serviço público da cidade de Recife, apesar de ser variado, é em sua maioria do sexo masculino, encaminhado por pediatras, com alteração de voz e idade entre 0 a 11 anos, apresentando frequentemente uma única queixa fonoaudiológica.

null

PURPOSE: to delineate the profile of patients registered and attended by a Speech Therapy sector in a public service at Recife. METHODS: the study was conducted from the collection and analysis of data concerning the origin of referral, age, gender, speech complaints of children, adolescents, adults and elderly, collected from the records of initial interviews. The sample consisted of all individuals registered in the sector of Speech Therapy in a public service at the city of Recife, from July 2007 to May 2008. RESULTS: from 251 patients attending the sector of Speech Therapy in a public service at Recife, 12 were excluded from the search because three were discharged and nine have not had full data. In the tested records, there was a greater number of referral performed by Pediatricians (25%), then Otorhinolaryngologist (16%) and General Clinical (10%), with the majority of males (61%), aged from 0 to 11-year old. According to the complaints, the most frequent was phonological diversion (14%), followed by language delay (11%), disfluency (10%) and oral respirator (8%). Regarding the number of complaints, 72% had one complaint, 25% had two complaints and 2% had three associated complaints. CONCLUSIONS: this research showed that the profile seen in the sector of spech therapy of a public service in the city of Recife, although varied, is mostly male, guided by pediatricians, with change of voice, age from 0 to 11-year old, often featuring a single speech therapy complaint.

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25

scielo_articles/scl/1516-1846/S1516-18462010000100017.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Barros, Percy Maria de Lima", "Oliveira, Priscila Nogueira de" ]

null

[ "Atenção Primária à Saúde", "Saúde Pública", "Setor Público", "Serviços de Saúde", "Reabilitação" ]

null

[ "Primary Health Care", "Public Health", "Public Sector", "Health Services", "Rehabilitation" ]

null

[ "Instituto de Reabilitação Infantil", "Instituto Materno Infantil de Pernambuco" ]

scl/1516-1846/S1516-18462010000100016.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100016

10.1590/S1516-18462009005000034

REHABILITATION

Universidade de Taubaté

Triagem auditiva neonatal universal: índice de efetividade no reteste de neonatos de um hospital da rede pública de Campinas

null

Universal neonatal screening: index of retest effectiveness among newborns of a public hospital in Campinas - Brazil

Berni, Paloma Savioli

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVOS: conhecer o índice de bebês avaliados na Triagem Auditiva Neonatal Universal de um hospital da rede pública de Campinas - São Paulo que concluíram o processo diagnóstico tendo falhado no teste de Emissões Otoacústicas Evocadas Transientes. MÉTODOS: a amostra é composta por 1146 protocolos de bebês avaliados no Programa de Triagem Auditiva Neonatal Universal desse hospital, no período de julho de 2007 a abril de 2008. RESULTADOS: a Triagem Auditiva Neonatal Universal mostrou efetividade de 69,4%, porém, a partir do reteste dos bebês que falharam, o índice de sucesso no seguimento cai acentuadamente. Do total da amostra, 11 bebês apresentaram suspeita de perda auditiva, dos quais quatro apresentaram alteração. CONCLUSÃO: os dados sugerem a necessidade de aperfeiçoamento do programa.

null

PURPOSE: to know the index of babies who failed in the EOAET diagnosis process in the Universal Neonatal Auditory Scan Program of an public hospital in Campinas, São Paulo, Brazil. METHODS: the sample is composed of 1146 protocols of babies evaluated in the Universal Neonatal Auditory Scan Program in this hospital, in the period of July 2007 to April 2008. RESULTS: Universal Neonatal Auditory Scan presented effectiveness of 69.4%, although the retest of the babies that failed in the EOAET diagnosis have shown that the success in the follow up process goes down significantly. From the total of the sample, 11 babies were suspected to have auditory loss and four had some alteration. CONCLUSION: data suggesting that the program needs to be improved.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100016&lng=en&tlng=en

23

scielo_articles/scl/1516-1846/S1516-18462010000100016.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Berni, Paloma Savioli", "Almeida, Elizabeth Oliveira Crepaldi de", "Amado, Bárbara Carolina Teixeira", "Almeida Filho, Nelson de" ]

null

[ "Audiologia", "Triagem Neonatal", "Recém-Nascido", "Diagnóstico Precoce", "Otolaringologia" ]

null

[ "Audiology", "Neonatal Screening", "Infant, Newborn", "Early Diagnosis", "Otolaryngology" ]

null

[ "Universidade de Taubaté", "Pontifícia Universidade Católica de Campinas", "Pontifícia Universidade Católica de Campinas" ]

scl/1516-1846/S1516-18462010000100015.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100015

10.1590/S1516-18462010000100015

REHABILITATION

Universidade de São Paulo

Emissões otoacústicas evocadas transientes em recém-nascidos a termo e pré-termo

null

Transient evoked otoacoustic emissions in full-term and preterm newborns

Melo, Ana Dolores Passarelli de

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: analisar a amplitude absoluta e nível de Response das emissões otoacústicas evocadas transientes em recém-nascidos pré-termo e a termo. MÉTODOS: participaram deste estudo 50 recém-nascidos a termo e 50 pré-termo, os quais foram submetidos à triagem auditiva neonatal por meio da pesquisa das emissões otoacústicas evocadas transientes, realizada entre 24 horas e 11 semanas de vida. Todos os recém-nascidos apresentaram presença de emissões otoacústicas evocadas por clique no teste da triagem auditiva neonatal. RESULTADOS: não houve diferença estatisticamente significante da amplitude e nível de Response entre os recém-nascidos a termo e pré-termos. Não houve correlação significante entre os fatores prematuridade, idade do recém-nascido no teste e tempo de estimulação auditiva com os resultados obtidos. CONCLUSÃO: as emissões otoacústicas evocadas transientes registradas em recém-nascidos a termos e pré-termos apresentam semelhante amplitude absoluta e nível de Response.

null

PURPOSE: to analyze the absolute amplitude and response level of transient evoked otoacoustic emissions in preterm and full-term newborns. METHODS: 50 full-term and 50 preterm newborns took part in the study. They underwent newborn hearing screening, through research of transient evoked otoacoustic emissions, performed between 24 hours and 11 weeks of life. All newborns showed transient evoked otoacoustic emissions in the newborn hearing screening test. RESULTS: no statistically significant difference of amplitude and response level was found between the full-term and preterm newborns. There was no significant correlation among factors such as prematurity, age of newborn at test and time of hearing stimulation with the results obtained. CONCLUSION: transient evoked otoacoustic emissions recorded in full-term and preterm newborns showed similar absolute amplitude and Response level.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100015&lng=en&tlng=en

27

scielo_articles/scl/1516-1846/S1516-18462010000100015.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Melo, Ana Dolores Passarelli de", "Alvarenga, Kátia de Freitas", "Modolo, Daniela Jovel", "Bevilacqua, Maria Cecília", "Lopes, Andréa Cintra", "Agostinho-Pesse, Raquel Sampaio" ]

null

[ "Audiologia", "Triagem Neonatal", "Prematuro" ]

null

[ "Audiology", "Neonatal Screening", "Infant, Premature" ]

null

[ "Universidade de São Paulo", "Universidade de São Paulo", "Universidade de São Paulo", "Universidade de São Paulo", "Universidade de São Paulo", "Universidade de São Paulo" ]

scl/1516-1846/S1516-18462010000100011.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100011

10.1590/S1516-18462010000100011

REHABILITATION

Universidade Estadual de Campinas

Comportamento dos músculos cervicais em indivíduos com fala esofágica e laringe artificial

null

Behavior of cervical muscles in individuals with esophageal speech and artificial larynx

Santos, Cristina Bellini dos

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: avaliar através da eletromiografia de superfície o comportamento dos músculos esternocleidomastóideo e paraespinhais cervicais bilateralmente em pacientes que se comunicam por meio da fala esofágica e laringe artificial, para determinar se o tipo de voz utilizada altera o comportamento dos músculos cervicais. MÉTODOS: foram avaliados dez voluntários (duas mulheres e oito homens), idade média de 49,7 anos, com laringectomia total, tempo de pós-operatório médio de 2,6 anos, com limitação dos movimentos do pescoço, divididos em dois grupos: grupo 1: cinco voluntários (laringe artificial); grupo 2: cinco voluntários (voz esofágica); grupo 3 controle (sete voluntários). RESULTADOS: na fonação não houve alteração no padrão de ativação muscular dos indivíduos que utilizam a voz esofágica e a laringe artificial, com relação ao grupo controle. No entanto, na condição de repouso houve diferença significativa, comparando-se os valores médios de Root Mean Square dos grupos 1 e 2 com o grupo 3, para o músculo esternocleidomastóideo direito e para os músculos paraespinhais cervicais direito. CONCLUSÃO: o tipo de opção vocal não interferiu no padrão de ativação muscular durante a fonação, bem como não existiu diferença no padrão de ativação muscular na fonação dos voluntários quando comparados a indivíduos sem intercorrências no aparelho fonador.

null

PURPOSE: to evaluate by the surface electromyography the behavior of the sternocleidomastoid and cervical paraspinalis muscles, bilaterally in patients who use esofagic and artificial larynx as alternative to talk and to determine if these conditions modify the cervical muscles behavior. METHODS: ten volunteers were evaluated (two women, eight men), with average age: 49. 7 years, with total laryngectomy, average time of postoperative: 2.6 years, with neck movements limitation, divided in two groups: group 1 with five volunteers (artificial larynx); group 2 with five volunteers (esofagic voice); and group 3 control (seven volunteers). RESULTS: there was no significant difference in the muscular activation pattern during phonation in individuals with esofagic voice and the artificial larynx compared to the control group, however, in the rest condition, there was a significant difference comparing the average values of Root Mean Square (RMS) of groups 1 and 2 with group 3, for the right sternocleidomastoid muscle and the right cervical paraspinalis muscles. CONCLUSION: the vocal option did not interfere on the muscular activation pattern during the phonation, as well as there was no difference in the muscular activation pattern comparing the experimental groups with the control group.

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31

scielo_articles/scl/1516-1846/S1516-18462010000100011.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Santos, Cristina Bellini dos", "Caria, Paulo Henrique Ferreira", "Tosello, Darcy de Oliveira", "Bérzin, Fausto" ]

null

[ "Eletromiografia", "Laringectomia", "Voz Esofágica", "Laringe Artificial" ]

null

[ "Electromyography", "Laringectomy", "Speech, Esophageal", "Larynx, Artificial" ]

null

[ "Universidade Estadual de Campinas", "Universidade Estadual de Campinas", "Universidade Estadual de Campinas", "Universidade Estadual de Campinas" ]

scl/1516-1846/S1516-18462010000100014.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100014

10.1590/S1516-18462009005000061

REHABILITATION

Pontifícia Universidade Católica de Campinas

Riscos ocupacionais à saúde e voz de professores: especificidades das unidades de rede municipal de ensino

null

Occupational risks to the health and voice of teachers: specificities of municipal education units

Servilha, Emilse Aparecida Merlin

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: comparar as condições de trabalho, saúde e voz em professores de diferentes escolas municipais. MÉTODOS: participaram 165 professores, média de 37 anos, casados, predomínio de mulheres e escolaridade superior da rede municipal de ensino de uma cidade do estado de São Paulo, que responderam ao questionário proposto por Ferreira et al (2003), abrangendo questões sócio-demográficas, situação funcional, aspectos vocais e de saúde. As respostas dos docentes foram separadas por unidade escolar e submetidas à análise estatística. RESULTADOS: constatou-se diferença significante entre as escolas quanto à presença de local para descanso, fiscalização constante e facilidade para se ausentar da sala de aula, número de alunos por classe (<0,001), ruído (0,002), iluminação (<0,001), limpeza (0,001), higiene nos sanitários (0,002), poeira (0,001), tamanho da sala (0,020), suficiência de espaço em classe (0,005), comprometimento dos funcionários com a manutenção da escola (0,033) e temperatura (<0,001). As menções de alteração vocal variaram de 76,47% a 40%, sem significância nos professores das diferentes escolas. Os problemas de saúde foram diversificados com diferença significante apenas para incômodo a sons (0,036). CONCLUSÃO: há riscos ocupacionais específicos relacionados à organização e ambiente de trabalho, nas distintas unidades escolares, que interferem na voz e saúde dos docentes, cujo desvelamento subsidia o gestor na implantação de ações contextualizadas, visando promover ambiente saudável para toda comunidade escolar.

null

PURPOSE: to compare the work, health and voice conditions of teachers from different city schools. METHODS: 165 teachers took part, mean age 37, married, predominance of women and university degree, from the city school system of a city from the state of São Paulo, who answered to the questionnaire proposed by Ferreira et al (2003), covering socio-demographic topics, functional situation, vocal and health aspects. The teachers' answers were separated by scholar unit and submitted to a statistical analysis. RESULTS: there was a significant difference among schools as for the presence of restrooms, constant surveillance and the ease of leaving the classroom, number of students per classroom (<0.001), noise (0.002), lightning (<0.001), cleaning (0.001), toilets' hygiene (0.002), dust (0.001), classroom size (0.020), space sufficiency in classrooms (0.033) and temperature (<0.001). The mentioning of vocal alteration varied from 76.47% to 40%, with no significance for teachers from different schools. The health problems were diversified with significant difference only to sound nuisance (0.036). CONCLUSION: there are specific occupational risks related to organizational and work environment in distinct scholar units that interfere in the docents' voice and health. By having this information the manager can implement contextualized initiatives in order to promote a healthy environment for all the scholar community.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100014&lng=en&tlng=en

24

scielo_articles/scl/1516-1846/S1516-18462010000100014.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Servilha, Emilse Aparecida Merlin", "Ruela, Isabela de Sousa" ]

null

[ "Distúrbios da Voz", "Docentes", "Riscos Ocupacionais" ]

null

[ "Voice Disorders", "Faculty", "Occupational Risks" ]

null

[ "Pontifícia Universidade Católica de Campinas", "Pontifícia Universidade Católica de Campinas" ]

scl/1516-1846/S1516-18462009000800015.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000800015

10.1590/S1516-18462009000800015

REHABILITATION

Universidade Federal de São Carlos

Análise comparativa da linguagem oral de crianças ouvintes e surdas usuárias de implante coclear

null

Comparative of verbal language analysis of listeners children and deaf children with cochlear implant

Fortunato, Carla Aparecida de Urzedo

2,009

12

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: analisar e comparar a expressão verbal de crianças ouvintes e crianças usuárias de implante coclear. MÉTODOS: os participantes foram 12 crianças ouvintes, entre 4 anos e 2 mês e 4 anos e 11 meses, e 10 crianças portadoras de perda auditiva neurossensorial profunda, usuárias de implante coclear, de 4 anos e 3 meses a 5 anos e 0 meses. As crianças foram avaliadas por meio da Escala de Expressão Verbal da Reynell Developmental Language Scales (RDLS), versão americana, adaptada por Fortunato-Queiroz (2007). Os dados dos dois grupos de crianças foram analisados e comparados entre si. RESULTADOS: as crianças surdas obtiveram um desempenho inferior ao das crianças ouvintes quanto à expressão verbal. Três crianças implantadas obtiveram resultados próximos ao considerado como padrão pela pesquisa, ou seja, aos resultados das crianças ouvintes. CONCLUSÃO: os resultados obtidos pelas crianças deficientes auditivas, usuárias de IC, foram inferiores aos seus pares ouvintes. As crianças surdas que apresentaram as maiores pontuações foram as que possuíam maior tempo de uso do IC e menor tempo de privação sensorial.

null

PURPOSE: to analyze and compare the verbal expression of children without hearing impairment and deaf children using cochlear implants. METHODS: the participants were twelve children without hearing impairment, with ages between four years two months and four years eleven months and ten deaf children using cochlear implants with age between four years and three months and five years and zero months. The children were evaluated using the Verbal Expression Scale of Reynell Developmental Language Scales (RDLS), American version, adapted by Fortunato-Queiroz (2007). The data of the two groups of children were analyzed and compared. RESULTS: the deaf children had a worse performance when compared to the children without hearing impairment. Three deaf children had results that approximate the results of the children without hearing impairment, accepted as normal standard in this work. CONCLUSION: the results of the deaf children using cochlear implants were inferiors yours pairs listeners. The deaf children who showed the biggest punctuations were the ones with shorter time of hearing sense deprivation and longer time using the cochlear implant.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462009000800015&lng=en&tlng=en

24

scielo_articles/scl/1516-1846/S1516-18462009000800015.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Fortunato, Carla Aparecida de Urzedo", "Bevilacqua, Maria Cecília", "Costa, Maria da Piedade Resende da" ]

null

[ "Implante Coclear", "Desenvolvimento da Linguagem", "Surdez" ]

null

[ "Cochlear Implantation", "Language Development", "Deafness" ]

null

[ "Universidade Federal de São Carlos", "Universidade de São Paulo", "Universidade de São Paulo" ]

scl/1516-1846/S1516-18462009000800014.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000800014

10.1590/S1516-18462009000800014

REHABILITATION

Pontifícia Universidade Católica de São Paulo

Estudo das emissões otoacústicas - produto de distorção durante a prática esportiva associada à exposição à música

null

Distortion product evoked otoacoustic emissions study with individuals of a fitness gym

Côrtes-Andrade, Isabela Freixo

2,009

12

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: estudar a audição dos alunos de uma academia de ginástica durante o exercício físico, analisando os resultados das emissões otoacústicas - produto de distorção (EOAPD), antes e após a exposição à música eletronicamente amplificada. MÉTODOS: foi aplicado um questionário em 20 indivíduos, sendo os mesmos avaliados por meio das EOAPD, antes e após a execução do exercício físico e exposição à música. RESULTADOS: uma elevada porcentagem de exposições extra-ocupacionais e de lazer (65%) foi encontrada ao analisar as queixas. Observou-se que 40% dos alunos de academia de ginástica apresentaram dores de cabeça e insônia; sete, intolerância para sons intensos; cinco, plenitude auricular e irritabilidade; cinco, nervosismo; quatro, tontura; e três relataram apresentar zumbidos após as aulas. No teste de EOPD, houve presença de respostas em 100% das orelhas testadas no momento 1 (M1), porém, no momento 2 (M2), houve presença de resposta em 75%. As frequências que apresentaram maior percentual de falhas no momento 2 (M2) foram 3KHz, 4KHz e 5 KHz. CONCLUSÃO: exercício físico associado a elevados níveis de pressão sonora de música provocam alterações nas EOA-PD, principalmente nas frequências de 3000Hz, 4000Hz e 5000Hz. Desse modo, alunos de academia de ginástica que ficam expostos à música eletronicamente amplificada podem estar prejudicando a audição. Há necessidade, portanto, das academias avaliarem as condições acústicas de suas salas de aulas, a partir da análise de profissionais especializados no intuito de verificarem os níveis sonoros, desse modo, observando se estes (NPS) estão compatíveis com os valores recomendados pela lei.

null

PURPOSE: to study the hearing of individuals in a fitness gym while exercising, analyzing their distortion product evoked otoacustic emissions (DPOAE) test after and before exposure to electronically amplified music. METHODS: a questionnaire was applied to 20 individuals and evaluated through DPOAE test after and before physical exercises with electronically amplified music exposure. RESULTS: most of the individuals (65%) had extra-occupational exposure. The most frequent complaints were headache and insomnia (40%); hearing difficulty (35%); aural fullness (25%); irritability and nervousness (25%); dizziness (20%); and tinnitus (15%) after exercises. Although DPOAE occurred in 100% of the ears before the exposure (moment 1 - M1), 25% failed on the second test, after the exercises (moment 2 - M2). The frequencies that most failed in the DPOAE test were 3 KHz, 4KHz and 5KHz. CONCLUSION: this study shows that individuals exposed to electronic amplified music, may have hearing loss complaints and have signs of such loss.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462009000800014&lng=en&tlng=en

29

scielo_articles/scl/1516-1846/S1516-18462009000800014.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Côrtes-Andrade, Isabela Freixo", "Souza, Aline da Silva de", "Frota, Silvana Maria Monte Coelho" ]

null

[ "Música", "Perda Auditiva", "Ruído", "Audição", "Ginástica" ]

null

[ "Music", "Hearing Loss", "Noise", "Hearing", "Gymnastics" ]

null

[ "Pontifícia Universidade Católica de São Paulo", "Universidade Veiga de Almeida", "Prefeitura Municipal de Armação de Búzios", "Universidade Federal do Rio de Janeiro", "Clínica de Fonoaudiologia e Audiologia" ]

scl/1516-1846/S1516-18462009000800013.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000800013

10.1590/S1516-18462009000800013

REHABILITATION

Universidade Estadual de Campinas

Triagem auditiva em escolares de 5 a 10 anos

null

Auditory assessment in the school-age children

Colella-Santos, Maria Francisca

2,009

12

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: analisar o desempenho de escolares na triagem auditiva, considerando-se o sexo masculino e feminino e a faixa etária-grupos I, II e III. MÉTODOS: foram avaliados 287 escolares de cinco a dez anos, do sexo feminino e masculino, que frequentavam o PRODECAD (Programa de Desenvolvimento e Integração da Criança e do Adolescente) da UNICAMP. A triagem auditiva foi constituída pela meatoscopia, imitanciometria - timpanometria e pesquisa do reflexo acústico, além dos testes que compõem a avaliação simplificada do processamento auditivo. RESULTADOS: na imitanciometria, 60,6% (N=174/287) dos escolares passaram. Constatou-se que houve diferença estatisticamente significante entre a curva timpanométrica e os grupos estudados. A curva do tipo A foi mais frequente nas crianças maiores, do grupo III. Além disso, o Grupo III apresentou maior número de resposta presente para o reflexo acústico, sendo a diferença entre os grupos estudados estatisticamente significantes. Observa-se que os escolares desse estudo apresentaram mais dificuldade em memorizar sequência de sons ou ordenação temporal do que localizar a fonte sonora. CONCLUSÃO: com base na análise dos resultados obtidos neste estudo foi possível concluir que na imitanciometria, 60,6% dos escolares passaram, ou seja, apresentaram condições de orelha média normais, além de integridade de vias auditivas até o tronco encefálico. Passaram na triagem do processamento auditivo, 56% dos escolares. Com relação aos grupos estudados, os grupos I e II apresentaram um número maior de crianças que falharam na triagem auditiva, considerando-se tanto a imitanciometria, como os testes de processamento auditivo.

null

PURPOSE: to analyze schoolchildren's performance in hearing screening, considering male and female genders and ages in groups I, II and III. METHODS: two-hundred and eighty-seven male and female schoolchildren, 5 to 10-year old, who attended the Child and Adolescent Program - University of Campinas (Prodecad/Unicamp), were evaluated. Hearing screening was constituted by meatoscopy, imitanciometry - tympanometry, and acoustic reflex research, in addition to tests which comprise the simplified evaluation of hearing process. RESULTS: considering imitanciometry, 60.6% of schoolchildren presented normal median ear conditions, in addition to integrity of hearing tracts up to encephalic trunk. Fifty-six percent of schoolchildren presented good results in the hearing screening process. Groups I and II presented a larger number of children who failed in hearing screening, considering either imitanciometry or hearing processing tests. CONCLUSION: hearing screening is an effective way to determine the adequate conduct to be adopted with schoolchildren regarding peripheral hearing loss and/or hearing abilities.

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27

scielo_articles/scl/1516-1846/S1516-18462009000800013.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Colella-Santos, Maria Francisca", "Bragato, Gisele Rasera", "Martins, Paula Maria Faria", "Dias, Amanda Ballarin" ]

null

[ "Audição", "Criança", "Percepção Auditiva", "Testes Auditivos", "Triagem" ]

null

[ "Hearing", "Child", "Auditory Perception", "Hearing Tests", "Triage" ]

null

[ "Universidade Estadual de Campinas" ]

scl/1516-1846/S1516-18462009000700009.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700009

10.1590/S1516-18462009000700009

REHABILITATION

Faculdade Integrada do Recife

Antropometria e mastigação em crianças asmáticas

null

Anthropometry and chewing in asthmatic children

Cunha, Daniele Andrade da

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVOS: caracterizar os padrões da antropometria facial em crianças asmáticas; identificar a presença de assimetrias faciais em crianças asmáticas e não asmáticas; e relacionar o lado de predomínio mastigatório com a presença de assimetria facial em crianças asmáticas e não asmáticas. MÉTODOS: participaram da pesquisa 60 crianças com idade entre 6 e 10 anos. Destas, 30 possuíam diagnóstico em prontuário de asma moderada ou grave e 30 crianças não apresentavam asma, fazendo parte do grupo controle. Foram realizadas avaliações antropométrica facial e da mastigação dessas crianças. RESULTADOS: em relação às mensurações antropométricas faciais nas crianças asmáticas e não-asmáticas não foram reveladas diferenças significativas entre os grupos. No que diz respeito à presença de assimetrias faciais, observou-se que estas ocorreram no grupo controle, assim como, no grupo asmático. O padrão mastigatório predominante em ambos os grupos foi o bilateral simultâneo e quando relacionados à assimetria facial e o predomínio mastigatório, não foram encontradas associações significantes. CONCLUSÃO: não foram encontradas diferenças significativas entre o grupo controle e o grupo asmático em relação às mensurações antropométricas. A assimetria facial foi observada nos dois grupos avaliados. Em ambos o padrão mastigatório bilateral simultâneo foi predominante, porém quando realizada a relação entre assimetria facial e o lado de predomínio mastigatório, não se observou relações significativas.

null

PURPOSES: to characterize the facial anthropometry patterns in asthmatic children; to identify the presence of facial asymmetry and to relate the prevalence of masticatory side with the presence of facial asymmetry in asthmatic and non-asthmatic children. METHODS: 60 children aged 6 to 10 years were evaluated. Thirty among them had a diagnosis of moderate or severe asthma and 30 children with no symptoms were the control group based on hospital's records. Facial anthropometric and chewing evaluations were carried through in these children. RESULTS: for facial anthropometric measurements in asthmatic and non-asthmatics children there were no significant differences between the groups but the finding of facial asymmetry was observed in both groups. The predominant masticatory pattern in both groups was the simultaneous bilateral and when it was related to facial asymmetry and masticatory predominance, there were no significant associations. CONCLUSION: no significant differences were found between the control and asthmatic group as for anthropometric measurements, however, the facial asymmetry was observed in the two groups. The simultaneous bilateral masticatory pattern was predominant in both groups, but the relation between facial asymmetry and the predominance of masticatory side were not significant.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462009000700009&lng=en&tlng=en

18

scielo_articles/scl/1516-1846/S1516-18462009000700009.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Cunha, Daniele Andrade da", "Lima, Renata Milena Freire", "Nascimento, Gerlane Karla Bezerra Oliveira", "Cunha, Renata Andrade da", "Silva, Elthon Gomes Fernandes da", "Silva, Hilton Justino da", "Prado, Isabella Jerônimo do", "Oliveira, Jabson Herber Profiro de", "Ferreira, Sheyla de Fátima Santos", "Moraes, Silvia Regina Arruda de", "Castro, Célia Maria Machado Barbosa de" ]

null

[ "Antropometria", "Mastigação", "Asma" ]

null

[ "Anthropometry", "Mastication", "Asthma" ]

null

[ "Faculdade Integrada do Recife", "Universidade Federal de Pernambuco", "Centro Especializado em Fonoaudiologia", "Faculdade Integrada do Recife", "Faculdade Integrada do Recife", "Universidade Federal de Pernambuco", "Universidade Federal de Pernambuco", "Universidade Federal de Pernambuco", "Universidade Federal de Pernambuco", "Universidade Federal de Pernambuco", "Universidade Federal de Pernambuco", "Universidade Federal de Pernambuco" ]

scl/1516-1846/S1516-18462009000700015.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700015

10.1590/S1516-18462009000700015

REHABILITATION

Secretaria Municipal de Saúde de Bauru

Relação entre perdas dentárias e queixas de mastigação, deglutição e fala em indivíduos adultos

null

Relation between tooth loss and chewing, swallowing and speech complaints in adults

Jorge, Tatiane Martins

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: investigar se as perdas dentárias em indivíduos adultos apresentam relação com as queixas de fala, mastigação e deglutição. MÉTODOS: participaram deste estudo 50 indivíduos adultos, trabalhadores de uma Avícola, do município de Bariri (SP), com faixa etária entre 18 e 52 anos. Os participantes selecionados foram submetidos à avaliação odontológica por um cirurgião-dentista e à entrevista fonoaudiológica, por duas fonoaudiólogas, em um consultório do município que mantém contrato de prestação de serviço com a Avícola. Para análise dos resultados, foram comparados os indivíduos com e sem perda dos elementos dentários, denominados de grupo experimental (GE) e grupo controle (GC), respectivamente, a partir da aplicação do teste Qui-Quadrado. RESULTADOS: os resultados revelaram maior ocorrência de mastigação unilateral no GE. Queixas quanto à dificuldade e dor na mastigação estiveram presentes apenas no GE, com diferença estatisticamente significante entre os grupos (p<0,05). O tempo de deglutição mostrou-se inadequado para a maioria dos indivíduos em ambos os grupos. A maioria dos indivíduos do GC mencionou utilizar algum tipo de líquido para facilitar a deglutição. Nenhum indivíduo mencionou queixas de fala. CONCLUSÃO: os achados revelaram que a ausência de elementos dentários em indivíduos adultos apresentou relação apenas entre dificuldade e dor durante a mastigação.

null

PURPOSE: to investigate if tooth absence in adults shows any relationship with chewing, swallowing and speech complaints. METHODS: 50 adults, who were poultry farm workers from Bariri municipality, in the State of São Paulo, Brazil, between the ages of 18 and 52, took part in this study. The selected participants were evaluated by a dentist and interview were carried out by two speech and language pathologist, in one of the municipality's office which has a contract of service rendering with the poultry farm. For analyzing the results, individuals with and without tooth loss, referred to as, respectively, the experimental group (EG) and the control group (CG), and were compared based on the performance of the Chi-Square test. RESULTS: the results revealed a higher occurrence of unilateral chewing in the EG (61.54%) and the chewing time showed itself inadequate for the most of the individuals in both groups. Claims of difficulties and pain in chewing were present only in the EG, which showed a statistically significant difference (p<0.05). Most of the individuals of the CG also mentioned the use of some drinking liquids to facilitate swallowing, without a statistically significant difference. There was no report of complaints related to speech in both groups. CONCLUSION: the findings revealed that the absence of teeth in adults showed relation only with the complaints with difficulty and pain during chewing.

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24

scielo_articles/scl/1516-1846/S1516-18462009000700015.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Jorge, Tatiane Martins", "Bassi, Ana Karolina Zampronio", "Yarid, Sérgio Donha", "Silva, Henrique Mendes", "Silva, Ricardo Pianta Rodrigues da", "Caldana, Magali de Lourdes", "Bastos, José Roberto de Magalhães" ]

null

[ "Perda de Dente", "Mastigação", "Deglutição" ]

null

[ "Tooth Loss", "Mastication", "Deglutition" ]

null

[ "Secretaria Municipal de Saúde de Bauru", "Universidade de São Paulo", "Universidade Estadual Paulista", "Universidade de São Paulo", "Secretaria Municipal de Saúde de Bariri", "Universidade de São Paulo", "Universidade de São Paulo" ]

scl/1516-1846/S1516-18462009000700014.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700014

10.1590/S1516-18462009000700014

REHABILITATION

CEFAC

Prevalência de alteração no frênulo lingual e suas implicações na fala de escolares

null

Prevalence of change in frenulun lingual and its implications in speech of school children

Braga, Lívia Augusta dos Santos

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVOS: verificar a prevalência do frênulo lingual alterado e suas implicações na fala de escolares. MÉTODOS: foram avaliados por três fonoaudiólogas os frênulos de língua de 260 crianças com idades variando entre 6 e 12 anos. Os frênulos foram classificados por meio de inspeção visual, medidas empregando-se paquímetro e avaliação da tensão, mobilidade e posicionamento da língua. Foram consideradas crianças com alteração de frênulo aquelas que apresentaram alteração em todas etapas da avaliação. Nos casos de classificação de frênulo alterado, a fala foi avaliada. RESULTADOS: os dados encontrados revelaram que das 260 crianças avaliadas 47 (18%), apresentaram alteração de frênulo, sendo 28 (60%), classificados como curtos; 12 (25%) como anteriorizados e 7 (15%) como curtos e anteriorizados. Não houve diferença entre os sexos. Dos indivíduos com frênulo alterado, 34 (72 %) apresentaram alteração de fala. A prevalência de alteração na fala foi maior no frênulo curto e anteriorizado (85%), seguido pelo curto (75%) e pelo anteriorizado (58%). As implicações de fala mais encontradas foram distorção e articulação trancada. CONCLUSÃO: foi verificada uma prevalência de 18% de alteração no frênulo lingual dentre os escolares avaliados, sem diferença entre os sexos. O frênulo curto predomina sobre os demais tipos, porém o curto e anteriorizado apresenta maiores implicações na fala. As características de fala mais comuns nestes casos são distorção e articulação trancada.

null

PURPOSE: to check the prevalence of altered tongue frenum and its implications on the scholar's speech. METHODS: tongue frenum of 260 children between 6 and 12 years old was evaluated by three speech therapists using visual inspection and caliper measurements. The children that showed changes in all stages of the evaluation were those considered to be with frenum alteration. The speech was evaluated in those children with altered tongue frenum. RESULTS: the found data revealed that from the 260 children, 47 (18%) had altered tongue frenum, being 28 (60%) classified as short, 12 (25%) as anterior and 7 (15%) as short and anterior. There weren't differences between sexes. Modifications on speech were seen in 34 children (72%) of those that had altered tongue frenum. The prevalence of speech alteration was higher in short and anterior frenum (85%) followed by short (75%) and anterior (58%). The most founded common speech implications were distortion and locked articulation. CONCLUSION: a prevalence of 18% in altered tongue frenum was verified among the evaluated scholars, with no differences between genders. The short frenum is the predominant type, although the short and anterior ones are more related to altered speech. The most common speech characteristics in these cases are distortion and locked articulation.

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32

scielo_articles/scl/1516-1846/S1516-18462009000700014.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Braga, Lívia Augusta dos Santos", "Silva, Jozi da", "Pantuzzo, Camila Leal", "Motta, Andréa Rodrigues" ]

null

[ "Prevalência", "Língua", "Freio Lingual", "Doenças da Língua", "Distúrbios da Fala", "Fonoterapia" ]

null

[ "Prevalence", "Tongue", "Tongue Frenum", "Tongue Diseases", "Speech Disorders", "Speech Therapy" ]

null

[ "CEFAC", "Universidade Federal de São Paulo", "Universidade Federal de Minas Gerais", "Clínica Psicopedagógica Barreiro", "Clínica Jozi da Silva", "Asilo Nossa Senhora da Piedade", "CEFAC", "CEFAC" ]

scl/1516-1846/S1516-18462009000700013.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700013

10.1590/S1516-18462009000700013

REHABILITATION

CERTO Odontologia

Estudo do posicionamento de língua e lábios em sujeitos com disfunção temporomandibular e dor orofacial

null

Study of tongue and lip positions in patients with temporomandibular disorder and orofacial pain

Matos, Vivian Ferreira

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: verificar a posição de repouso de língua e lábios em sujeitos com Disfunção Temporomandibular (DTM) e analisar a intensidade da dor em músculos mastigatórios. MÉTODOS: foram avaliados 44 sujeitos de ambos os sexos com média de idade de 42,52 anos. Foram realizadas três avaliações: exame clínico visual, averiguando a posição de repouso da língua, seguido de avaliação subjetiva e objetiva da dor pela Escala Visual Analógica (EVA) e palpação dos músculos mastigatórios. RESULTADOS: 23 (52,27%) posicionaram a língua no palato e 21 (47,73%) na posição baixa. Dos sujeitos que posicionaram a língua no palato, 73,91% deles referiram dor à palpação em masseter; 56,52% na região cervical; 43,48% em temporais; 39,13% em digástricos e 52,17% em região articular. Encontraram-se relações estatisticamente significantes entre queixa subjetiva e objetiva da dor relativo aos músculos cervicais (p=0,026), temporais (p=0,019), digástricos (p=0,005) e região articular (p=0,013). Na amostra foram encontrados 88,63% de componente miálgico e 56,81% artrálgico. CONCLUSÃO: a posição não elevada da língua não se confirmou em pacientes com DTM, uma vez que a distribuição foi equitativa, com ausência de correlação entre dor e posição de língua, predomínio de lábios fechados e dores miálgicas mais freqüentes que as artrálgicas.

null

PURPOSE: to check the habitual tongue and lips rest position in subjects with Temporomandibular Dysfunction (TMD), and to analyze their pain complaint in masticatory muscles. METHODS: 44 subjects, of both genders and mean age of 42.52 years were evaluated. Three evaluations were carried out: visual clinical examination as for tongue habitual rest position, pain complains using visual analogical scale (VAS) and bilateral masticatory muscle palpation assessing pain intensity. RESULTS: 23 subjects (52.27%) showed the tongue at the palatine papilla and 21 (47.73%) showed in different position than the elevated. The subjects who showed the tongue against the palatine papilla, referred pain during the palpation of Masseters (73.91%), Cervical muscles (56.52%), Temporals (43.48%), Digastrics muscles (39.13%) and in the Temporomandibular Joint (TMJ) region (52.17%). Statistically significant correlations were found among pain complains (VAS) and palpation pain intensity concerning: Cervical Muscles (p=0.026), Temporals (p=0.019), Digastrics (p=0.005) and TMJ region (p=0.013). The sample demonstrated components comprising 88,63% of masticatory muscle pain and 56.81% complained pain in the Temporomandibular Joint region. CONCLUSION: the non-elevated position of the tongue was not confirmed in TMD subjects, with no correlation between pain and tongue rest position. We observed closed lips rest position and predominance of mialgic pain instead of arthralgic pain.

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26

scielo_articles/scl/1516-1846/S1516-18462009000700013.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Matos, Vivian Ferreira", "Sekito, Florence Mitsue" ]

null

[ "Língua", "Dor Facial", "Síndrome da Disfunção da Articulação Temporomandibular" ]

null

[ "Tong", "Facial Pain", "Temporomandibular Joint Dysfunction Syndrome" ]

null

[ "CERTO Odontologia", "CEFAC", "Universidade Estadual do Rio de Janeiro" ]

scl/1516-1846/S1516-18462009000700012.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700012

10.1590/S1516-18462009000700012

REHABILITATION

Clínica Fonoaudiológica Cross

Frênulo de língua alterado e interferência na mastigação

null

Lingual frenulum alteration and chewing interference

Silva, Margaret Cross

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: verificar se indivíduos com alteração do frênulo da língua apresentam alteração na mobilidade da língua e na mastigação. MÉTODOS: a casuística desta pesquisa foi composta por dois grupos, um alvo e outro controle, cada um deles com 10 indivíduos. O grupo alvo apresentava alteração de frênulo da língua. Todos foram submetidos aos protocolos de avaliação de frênulo da língua e de mastigação. As provas de mobilidade da língua e de mastigação foram filmadas. Todos os frênulos da língua foram fotografados. RESULTADOS: os dados coletados mostraram que os indivíduos com alteração do frênulo têm 5,447 vezes mais chance de apresentar alteração na mobilidade da língua que indivíduos com frênulo normal. Os indivíduos com alterações da mobilidade da língua não mantiveram constância quanto ao tempo mastigatório. Quanto à mastigação no Modo de Trituração, 100% dos indivíduos do grupo controle utilizaram os dentes posteriores. Entre os indivíduos com alteração do frênulo da língua, 47% mastigaram usando os dentes posteriores e 53% utilizaram os dentes anteriores e/ou fizeram amassamento com a língua. Com relação as atipias musculares, os indivíduos com alteração de frênulo possuíram 5,714 vezes mais chance de apresentá-las durante a mastigação que os indivíduos do grupo controle. CONCLUSÃO: indivíduos com alterações do frênulo da língua apresentaram alterações dos movimentos da língua e alterações na mastigação.

null

PURPOSE: to check if individuals with lingual frenulum alteration demonstrate chewing interference. METHODS: the casuistry of this research was carried out with two groups, a target and a control group, each one with ten individuals. The target group had lingual frenulum alteration. All subjects were submitted to lingual frenulum and chewing evaluation protocols. This procedure was recorded. RESULTS: the collected samples showed that individuals with lingual frenulum alteration have 5.447 times more chances of show tongue mobility alteration than individuals with normal frenulum. Subjects with tongue mobility alteration haven't kept regularity when it comes to mastication period. As for the chewing, on the grinding mode, 100% of the control group used the back teeth. Among the subjects with frenulum alteration, 47% used the back teeth and 53% chewed with the front teeth and/or mashing with the tongue. Regarding muscle atypical movements, individuals with frenulum alteration have 5.714 times more chances to show them during the chewing than individuals from the control group. CONCLUSION: individuals with lingual frenulum alteration showed tongue mobility alteration and mastication alterations.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462009000700012&lng=en&tlng=en

26

scielo_articles/scl/1516-1846/S1516-18462009000700012.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Silva, Margaret Cross", "Costa, Maria Lúcia Venceslau Carvalho Martins da", "Nemr, Kátia", "Marchesan, Irene Queiroz" ]

null

[ "Freio Lingual", "Mastigação", "Sistema Estomatognático", "Limitação da Mobilidade", "Avaliação" ]

null

[ "Lingual Frenum", "Mastication", "Stomatognathic System", "Mobility Limitation", "Evaluation" ]

null

[ "Clínica Fonoaudiológica Cross", "CEFAC", "Universidade de São Paulo", "Instituto CEFAC" ]

scl/1516-1846/S1516-18462009000700011.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700011

10.1590/S1516-18462009000700011

REHABILITATION

Universidade Estadual de Campinas

Estudo eletromiográfico da deglutição na musculatura supra-hióidea em sujeitos Classe Ie III de Angle

null

Electromyographic study of swallowing in suprahyoid musculature in Angle's Class I and III subjects

Nagae, Mirian Hideko

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: comparar a atividade elétrica do músculo supra-hióideo durante a deglutição em sujeitos com distintos padrões morfológicos e dentários. MÉTODOS: foram realizados registros eletromiográficos de superfície em 32 voluntários saudáveis e sem Disfunção Temporomandibular, subdivididos em dois grupos, 16 sujeitos Classes I e 16 Classe III de Angle, gênero masculino e feminino, com faixa etária entre 18 e 25 anos de idade. RESULTADOS: foram obtidos os valores do Root Mens Square (p< 0,05): original Classe I (15,238) e Classe III (32,550); normalizado pelo pico máximo Classe I (29,765) e Classe III (42,094); normalizado pela média Classe I (29,332) e Classe III (42,327). Período ativo do ciclo (p<0,05) Classe I (29,7648) e Classe III (42,0937); instante de máxima atividade (p>0,05) Classe I (47,6485) e Classe III (47,9437). CONCLUSÃO: os sujeitos Classe I demonstraram uma amplitude média menor, com aumento e diminuição da atividade elétrica sincrônica e equilibrada. Os sujeitos Classe III apresentaram uma amplitude média e um período ativo maior, assincrônico e desequilibrado durante a deglutição.

null

PURPOSE: to compare Suprahyoid musculature's electric activity during swallowing in subjects with dissimilar morphological and dental patterns. METHODS: surface Electromyography's records were taken from 32 healthy volunteers who do not have Temporomandibular Dysfunction, subdivided into two groups, Angle's 16 Class I subjects and 16 Class III subjects, males and females, aging from 18 to 25-year old. RESULTS: the values to Root Mens Square (p< 0.05): original Class I (15.238) e Class III (32.550); normalized by maximum peak Class I (29.765) e Class III (42.094); normalized by medium Class I (29.332) e Class III (42.327). Cycle's active period (p<0.05) Class I (29.7648) e Class III (42.0937); maximum activity instance (p>0.05) Class I (47.6485) e Class III (47.9437). CONCLUSION: class I subjects showed a smaller average amplitude, with increase and decrease of synchronized and balanced electric activity. Class III subjects showed a larger average amplitude and a larger desynchronized and unbalanced period during deglutition.

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39

scielo_articles/scl/1516-1846/S1516-18462009000700011.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Nagae, Mirian Hideko", "Alves, Marcelo Corrêa" ]

null

[ "Deglutição", "Má Oclusão de Angle Classe III", "Eletromiografia" ]

null

[ "Deglutition", "Malocclusion, Angle Class III", "Electromyography" ]

null

[ "Universidade Estadual de Campinas", "Universidade Estadual de Campinas", "Faculdade Anhanguera de Piracicaba" ]

scl/1516-1846/S1516-18462009000700010.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700010

10.1590/S1516-18462009000700010

REHABILITATION

Pontifícia Universidade Católica de São Paulo

Relação entre cefalometria e análise facial na determinação do tipo de face

null

Relation between cephalometry and facial analysis on the facial type determination

Ramires, Rossana Ribeiro

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: correlacionar os achados cefalométricos com os da análise facial realizada por meio de fotografias para classificar o tipo facial, segundo o sexo. MÉTODOS: participaram 105 adultos leucodermas, 34 (32,4%) homens e 71 (67,6%) mulheres, com idades entre 20 e 40 anos, de uma clínica particular de ortodontia de Belo Horizonte/MG. Os achados da análise cefalométrica para determinação do tipo facial a partir do índice VERT de Ricketts foram comparados com a classificação da face realizada por meio da análise facial clínica baseada na observação de duas fotografias. Para essa análise, participaram três fonoaudiólogos especialistas em motricidade orofacial. RESULTADOS: não houve correspondência satisfatória ao se comparar as duas formas de classificação do tipo facial apresentadas neste estudo. A maioria dos indivíduos masculinos dolicofaciais foi classificada como face média a partir da análise facial, ou seja, quatro entre sete sujeitos (57,14%). Os 11 mesofaciais foram identificados como face média (N=5; 45,45%) ou curta (N=4; 36,36%) e os 16 braquifaciais como face média (N=9; 56,25%) ou curta (N=7; 43,75%). No sexo feminino, observou-se que 11 entre 20, ou seja, 55% dos indivíduos dolicofaciais foram apontados como face média. Dos 26 sujeitos mesofaciais, 16 (61,53%) também foram classificados como face média. Com relação aos 25 braquifaciais, 12 (48%) foram identificados como face curta e 11 (44%), como média. CONCLUSÃO: a classificação do tipo de face apenas a partir da análise facial realizada por meio de fotografias não foi considerada confiável, se utilizada isoladamente, quando comparada à classificação obtida a partir da análise cefalométrica.

null

PURPOSE: to correlate the cephalometrical findings with the ones from facial analysis performed by means of photographs to classify facial type, according to the gender. METHODS: 105 leukoderm adults took part, 34 male (32.4%) and 71 female (67.6%) with ages between 20 and 40 years old, in a private orthodontic clinic in Belo Horizonte, MG - Brazil. The cephalometrics analysis findings for determining facial type from the Ricketts VERT index were compared with the facial classification performed by means of clinical facial analysis based on observation of two photographs. For this analysis, three Speech and Language Pathologists specialized in orofacial myology were involved. RESULTS: there was no satisfactory correspondence when comparing the two forms of facial type classification presented in this study. Most of the dolichofacial males were classified as medium face by means of facial analysis, meaning four among seven subjects (57.14%). The eleven mesofacial subjects were identified as medium face (N=5; 45.45%) or short (N=4; 36.36%) and the 16 braquifacial subjects as medium face (N=9; 56.25%) or short (N=7; 43.75%). With females, it was observed that 11 among 20, meaning 55% of the dolichofacial individuals were appointed as medium face. Among the 26 mesofacial subjects, 16 (61.53%) were also classified as medium face. Regarding the 25 braquifacial subjects, 12 (48%) were identified as short face and 11 (44%), as medium. CONCLUSION: facial type classification based only on facial analysis performed by means of photographs was not considered trustworthy, if used independently, when compared with cephalometrics analysis findings.

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34

scielo_articles/scl/1516-1846/S1516-18462009000700010.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Ramires, Rossana Ribeiro", "Ferreira, Léslie Piccolotto", "Marchesan, Irene Queiroz", "Cattoni, Débora Martins", "Silva, Marta Assumpção de Andrada e" ]

null

[ "Face", "Morfologia", "Adulto", "Circunferência Craniana", "Fotografia", "Estudo Comparativo" ]

null

[ "Face", "Morphology", "Adult", "Cephalometry", "Photography", "Comparative Study" ]

null

[ "Pontifícia Universidade Católica de São Paulo", "Santa Casa de Misericórdia de São Paulo", "CEFAC", "CEFAC", "Pontifícia Universidade Católica de São Paulo", "Pontifícia Universidade Católica de São Paulo", "CEFAC" ]

scl/1516-1846/S1516-18462009000700008.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700008

10.1590/S1516-18462009000700008

REHABILITATION

Universidade Estadual de Campinas

Mastigação e atividade eletromiográfica em crianças com mordida cruzada posterior

null

Mastication and electromyographic activity in children with posterior crossbite

Trawitzki, Luciana Vitaliano Voi

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: investigar a preferência mastigatória e o comportamento dos músculos mastigatórios, em crianças de 6 a 9 anos, com mordida cruzada posterior. MÉTODOS: 30 crianças foram selecionadas num serviço de Ortodontia de uma universidade pública. Após a concordância na participação no trabalho, foi realizada entrevista com a criança e seu responsável, para investigação de disfunção temporomandibular; análise da preferência mastigatória, por meio de registros em vídeo e avaliação eletromiográfica (EMG) dos músculos masseter e temporal anterior, durante a mastigação solicitada, direita e esquerda, de uma goma de marcar. RESULTADOS: houve diferença significante na atividade EMG dos músculos masseter e temporal anterior entre os lados de trabalho e balanceio, porém não houve diferença estatística quando foram comparadas as atividades EMG entre os lados de mordida cruzada e não cruzada, tampouco entre os lados de preferência e não preferência mastigatória. CONCLUSÃO: na amostra estudada não se verificou assimetria funcional muscular estabelecida.

null

PURPOSE: to investigate the masticatory preference and the behavior of masticatory muscles, in children between6 to 9-year old, with posterior crossbite. METHODS: 30 children were selected from the Orthodontical service of a public university. After consenting to take part in the study, there was an interview with the children and the parent, in order to investigate temporomandibular disorders; masticatory was analyzed through video recording and electromyographic (EMG) evaluation of the masseter and anterior temporal, during the solicited mastication, on right and left, using chewing gum. RESULTS: there was a significant difference in the EMG activity of the masseter and temporal between work and balance sides, however there was no statistical differences in the comparison between crossbite side and no crossbite side, but neither between preference side and non the preference side. CONCLUSION: in the studied population there was no functional muscular asymmetry established.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462009000700008&lng=en&tlng=en

31

scielo_articles/scl/1516-1846/S1516-18462009000700008.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Trawitzki, Luciana Vitaliano Voi", "Felício, Cláudia Maria de", "Puppin-Rontani, Regina Maria", "Matsumoto, Mirian Aiko Nakane", "Vitti, Mathias" ]

null

[ "Eletromiografia", "Músculos", "Mastigação" ]

null

[ "Electromyography", "Muscles", "Mastication" ]

null

[ "Universidade Estadual de Campinas", "Universidade de São Paulo", "Universidade de São Paulo", "Universidade de São Paulo", "Universidade de São Paulo" ]

scl/1516-1846/S1516-18462009000700017.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700017

10.1590/S1516-18462009000700017

REHABILITATION

Faculdade Integrada do Recife

Adaptações na mastigação, deglutição e fonoarticulação em idosos de instituição de longa permanência

null

Chew, deglutition and speech adaptations in aged people at a long permanence institution

Lima, Renata Milena Freire

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: identificar adaptações existentes nas funções estomatognáticas de mastigação, deglutição e fonoarticulação em idosos de Instituição de longa permanência. MÉTODOS: participaram da pesquisa 34 idosos, sendo 15 do sexo feminino e 19 do sexo masculino na faixa etária de 65 a 88 anos. Foram realizadas entrevistas contendo perguntas sobre a saúde geral e alimentação do idoso e avaliações fonoaudiológicas a fim de caracterizar as funções de mastigação, deglutição e fonoarticulação. RESULTADOS: em relação à mastigação, foi observado que a maioria dos idosos apresentou mastigação adaptada, com participação exagerada da musculatura perioral, movimentos mandibulares verticais e o padrão mastigatório predominante foi bilateral simultâneo. Em relação à deglutição, observou-se que assim como a mastigação, esta função se apresentou adaptada na maioria dos voluntários, com a participação exagerada da musculatura perioral e ruído durante a deglutição. Na avaliação da fonoarticulação, foi visto que mais de 50% dos idosos apresentou escape de ar durante a fala, assim como uma elevação de laringe reduzida e presença de substituição, omissão, distorção e imprecisão. CONCLUSÃO: observou-se que os idosos se adaptam durante o processo de mastigação a fim de manter sua dieta o mais próximo possível da realizada quando jovem. Também foi visto que os pesquisados realizam compensações durante a deglutição. As características fonoarticulatórias encontradas não limitam severamente a comunicação dos idosos atualmente. Foi possível ainda observar que o atendimento ao idoso necessita ser interdisciplinar e que o fonoaudiólogo pode e deve fazer parte dessa equipe auxiliando na prevenção e/ou reabilitação de problemas relacionados às funções estomatognáticas.

null

PURPOSE: to identify extant adaptations into stomatognathic functions of chew, deglutition and speech in aged people at a long permanence Institution. METHODS: 34 aged people, of both genders, being 15 feminine and 19 masculine, with ages ranging from 65 to 88 years, took part in the study. Interviews were carried through containing questions for the aged people on general health and feeding and speech therapy evaluations were performed in order to characterize functions of chew, deglutition and speech. RESULTS: as for chew, it was observed that the majority of aged people showed an adapted chew, with exaggerated participation of perioral muscles, heaves of jaw and predominant chew standard was bilateral simultaneous. As for deglutition, it was observed that this function as well as chew were an adapted form into the majority of volunteers majority, we also observed the occurrence of exaggerated participation of perioral muscles and noise during deglutition. In speech evaluation we noted that in more than 50% of the aged people, there was great air escape occurring during speaks, as well as a rise of reduced larynx and the presence of substitution, omission, distortion and imprecision. CONCLUSION: it was observed that aged people get adaptations during chew process in order to keep their possible diet next to when they were young. It was also noted that the studied aged people carry through some compensations during deglutition. The found speech characteristics do not limit severely aged people communication currently. It was still possible to observe that attendance to aged people needed to be carried through by an interdisciplinary team and that speech therapist can and must be part of this team assisting in preventing and/or rehabilitating issues related to stomatognathic functions.

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28

scielo_articles/scl/1516-1846/S1516-18462009000700017.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Lima, Renata Milena Freire", "Amaral, Ana Karênina de Freitas Jordão do", "Aroucha, Edylla Barbosa Lins", "Vasconcelos, Tirza Malta Jordão de", "Silva, Hilton Justino da", "Cunha, Daniele Andrade da" ]

null

[ "Mastigação", "Deglutição", "Fala", "Idoso" ]

null

[ "Mastication", "Deglutition", "Speech", "Aged" ]

null

[ "Faculdade Integrada do Recife", "Universidade Federal de Pernambuco", "Faculdade Integrada do Recife", "Faculdade Integrada do Recife", "Faculdade Integrada do Recife", "Clínica Renata Milena Freire Lima", "Centro de Reabilitação Francisco Loreiro", "Universidade Federal de Pernambuco", "Universidade Federal da Paraíba", "Faculdade Integrada do Recife" ]

scl/1516-1846/S1516-18462009000700007.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000700007

10.1590/S1516-18462009000700007

REHABILITATION

Universidade Veiga de Almeida

Caracterização da função mastigatória em crianças com dentição decídua e dentição mista

null

Characteristics of masticatory function in children with deciduous and mixed dentition

Gomes, Lissandra Montagneri

2,009

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: caracterizar a mastigação de crianças com dentição decídua e com dentição mista, buscando verificar se há variações inerentes ao processo de desenvolvimento desta função. MÉTODOS: participaram 78 crianças, 4 a 11 anos, ambos os gêneros, divididas em dois grupos: GI - dentição decídua completa e GII - dentição mista. Foi realizada inspeção visual das estruturas do sistema estomatognático seguida da avaliação da mastigação, utilizando-se pão francês. A coleta dos dados foi realizada por meio da observação visual direta e registro em vídeo, visando confirmação dos dados observados, analisando-se os seguintes dados durante a mastigação: tipo de mordida, postura de lábios, amassamento com a língua, quantidade ingerida, padrão mastigatório, ciclos mastigatórios, movimentos mandibulares, uso dos dedos para juntar o alimento e verificação de movimentação exagerada da musculatura perioral. RESULTADOS: pode-se considerar que crianças de G1 e G2 apresentam as seguintes características: mordida frontal, porção média de alimento, presença de vedamento labial, média de 27 ciclos mastigatórios por porção, movimentos mandibulares rotatórios, ausência de amassamento do alimento com a língua, ausência da utilização dos dedos para juntar o alimento e ausência de uso exagerado da musculatura perioral. Não foram encontradas diferenças estatisticamente significantes entre as características mastigatórias dos dois grupos, sendo que apenas a presença de amassamento do alimento com a língua é predominante na dentição decídua. CONCLUSÃO: parece não existir diferenciação das características quanto ao padrão mastigatório em relação às fases de dentição estudadas, sendo apenas o amassamento do alimento mais frequente na decídua.

null

PURPOSE: to raise and to characterize the chewing pattern in children with deciduous and mixed dentition. METHODS: 78 children, from 4 to 11-year old, both genders, divided in two groups: GI: children with complete deciduous dentition and GII: with mixed dentition. Visual inspection of the stomatognathic system was followed by the evaluation of chewing, using three portions of French bread, with the first portion ignored. Data analysis was carried through visual observation and video recording, in order to review and confirm the observed characteristics. The following items were analyzed: type of bite, lips' position, kneading with the tongue, ingested amount, chewing pattern, number of chewing cycles, mandibular movements, the use of fingers to join food and verification of overstated movement of the perioral muscles. RESULTS: we can consider that children of GI and GII have the following characteristics: frontal bite, regular amount of food, presence of lips closed, average of 27 chewing cycles for portion, rotatory mandible movements, absence of food tongue kneading, no use of fingers to join the food and no overstated movements of the perioral muscles. Significant statistical differences were not found between the two groups. Only the presence of kneading food with the tongue is more common in deciduous dentition. CONCLUSION: it seems that there are no differences of the chewing pattern characteristics in relation to the dentition phase, considering deciduous or mixed dentition, excepting food kneading with the tongue that is more frequent in deciduous dentition.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462009000700007&lng=en&tlng=en

24

scielo_articles/scl/1516-1846/S1516-18462009000700007.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Gomes, Lissandra Montagneri", "Bianchini, Esther Mandelbaum Gonçalves" ]

null

[ "Mastigação", "Criança", "Dentição", "Dentição Primária", "Dentição Mista", "Sistema Estomatognático" ]

null

[ "Mastication", "Child", "Dentition", "Dentition Primary", "Dentition, Mixed", "Stomatognathic System" ]

null

[ "Universidade Veiga de Almeida", "Hospital do Câncer" ]

scl/1516-1846/S1516-18462010000100013.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100013

10.1590/S1516-18462010000100013

REHABILITATION

Governo do Estado do Rio de Janeiro

Prevalência de disfonia em professores do ensino público estadual afastados de sala de aula

null

Prevalence of vocal dysfunction in teachers from the state education, licensed from classroom

Provenzano, Lucia Cristina Fernandes Antunes

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: identificar a prevalência da disfonia, gerando afastamento de sala de aula, em docentes do Ensino Médio da Rede Estadual de Educação. MÉTODOS: foi realizado um levantamento exploratório de prontuários médicos de professores afastados de sala de aula, durante os anos de 2005 e 2006, registrados na Superintendência Central de Perícias Médicas e Saúde Ocupacional do Estado do Rio de Janeiro. De uma amostra total de 554 professores lecionando durante o período analisado, foram pesquisados 130 prontuários de docentes licenciados por diversos diagnósticos, procurando-se identificar os afastamentos com diagnóstico médico de disfonia. RESULTADOS: evidenciou-se que, apesar das elevadas taxas de prevalência de sinais e sintomas vocais negativos entre os professores relatados em outras pesquisas, apenas 6,9% afastaram-se de sala de aula por disfonia. Os resultados possibilitam, ainda, reflexões acerca da relação existente entre voz, corpo, respiração e emoção, no contexto da docência. CONCLUSÃO: conclui-se que mesmo a disfonia sendo um problema frequente no trabalho docente, pouco se conhece sobre os dados oficiais de professores afastados de sala de aula por esse comprometimento. Torna-se necessário maior número de pesquisas para que os responsáveis por decisões políticas, sejam alertados e sensibilizados quanto à importância do assunto, em termos sociais e econômicos para o País. Ressalta-se a necessidade de que o trabalho fonoaudiológico desenvolvido com os professores tenha cunho transdisciplinar, e que, de forma intersetorial e harmônica, programas e políticas de prevenção e promoção da saúde vocal possam ser oferecidos à classe docente.

null

PURPOSE: to identify the prevalence of the vocal dysfunction which caused medical leave among high school teachers from the "State Education System". METHODS: a survey was conducted analyzing school teachers' medical reports who were licensed for medical leave in 2005 and 2006 which were registered in the "Central Superintendence of Medical Expert Reports and Occupational Health of the State of Rio de Janeiro". From 554 school working teachers in the above-mentioned period, 130 medical reports were analyzed and on a leave because of several vocal dysfunctions diagnostics, trying to identify the medical leaves arising from vocal dysfunction. RESULTS: it was clear that despite of the high prevalence rate of the negative vocal sign symptoms among school teachers, just 6.9% were on a leave due to vocal dysfunction. The results also allow for reflections on the relation amongst voice, body, breathing and emotion in the teaching world. CONCLUSION: it may be concluded that even when dysphonia usually a problem in the educational work, we know very little on official data concerning teachers who are licensed for medical leave. More research is required for the ones who are responsible for policy decisions, to be aware and sensible to the importance of the issue, for the country, in social and economics terms. We emphasize the need for speech therapist work development among school teachers to be a multidisciplinary job, with prevention programs and policies that are very important to implement and also to promote vocal health programs that may be offered to school teachers.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100013&lng=en&tlng=en

34

scielo_articles/scl/1516-1846/S1516-18462010000100013.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Provenzano, Lucia Cristina Fernandes Antunes", "Sampaio, Tânia Maria Marinho" ]

null

[ "Voz", "Distúrbios da Voz", "Educação" ]

null

[ "Voice", "Voice Disorders", "Education" ]

null

[ "Governo do Estado do Rio de Janeiro", "Universidade Federal Fluminense" ]

scl/1516-1846/S1516-18462010000100010.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100010

10.1590/S1516-18462010000100010

REHABILITATION

Universidade de São Paulo

Protocolo para controle de eficácia terapêutica em disfagia orofaríngea neurogênica (PROCEDON)

null

Efficacy control protocol in oropharyngeal dysphagia

Silva, Roberta Gonçalves da

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: apresentar uma proposta para o controle de eficácia terapêutica em disfagia orofaríngea neurogênica. MÉTODOS: o protocolo foi proposto em concordância com a literatura atual e aplicado em um indivíduo pós-acidente vascular encefálico (AVE) isquêmico à direita, comprovado por tomografia computadorizada, com disfagia orofaríngea grave crônica, gênero masculino, 66 anos, apresentando aspiração laringotraqueal e em uso de sonda nasoentérica exclusiva pré-fonoterapia. Para controle da eficácia terapêutica do programa de reabilitação fonoaudiológica foi aplicado, pré e pós-fonoterapia, a classificação do grau de comprometimento da disfagia orofaríngea, Functional Oral Intake Scale (FOIS), a avaliação videofluoroscópica da deglutição com medida do tempo de trânsito faríngeo (TTF) da deglutição por meio de software e da percepção do indivíduo. RESULTADOS: na pré-fonoterapia verificou-se disfagia orofaríngea grave, FOIS nível 1, presença de aspiração laringotraqueal para mais de uma consistência e tempo de trânsito faríngeo de 13 segundos. Após fonoterapia verificou-se disfagia orofaríngea moderada, FOIS nível 5, ausência de aspiração laringotraqueal e TTF de 4 segundos. CONCLUSÃO: o protocolo proposto foi capaz de avaliar a eficácia da reabilitação na disfagia orofaríngea neurogênica neste indivíduo pós-acidente vascular encefálico, tanto para mensurar as mudanças ocorridas na fisiopatologia da deglutição quanto na ingestão oral e na percepção do indivíduo. Outros estudos com populações distintas são necessários, sendo que novas propostas devem ainda refletir a inclusão da condição nutricional e pulmonar do indivíduo no controle de eficácia em disfagia orofaríngea.

null

PURPOSE: to submit a proposal for efficacy control in neurogenic oropharyngeal dysphagia. METHODS: the protocol was proposed in accordance with other researches and applied in one post-stroke individual, with right-hemispheric lesion confirmed by computed tomography, with oropharyngeal dysphagia, male gender, 66-year old, with laringotraqueal aspiration and using nasogastric feeding tube before swallowing therapy. In order to control the therapy effectiveness in pre- and post-swallowing therapy, the following procedures were applied: classification of severity degree for oropharyngeal dysphagia, functional oral intake scale (FOIS), videofluoroscopic evaluation of swallowing with additional swallowing pharyngeal transit time evaluation using a specific software and individual perception. RESULTS: before swallowing therapy, severe oropharyngeal dysphagia, FOIS level 1, presence of laryngotracheal aspiration, and 13 seconds of pharyngeal transit time were found. After swallowing therapy, moderate oropharyngeal dysphagia, FOIS level 5, absence of laryngotracheal aspiration, and 4 seconds of pharyngeal transit time were found. CONCLUSION: the proposed protocol could measure changes, both for pathophysiology of swallowing as well as for oral ingestion of the individual. We believe that it is still necessary to include nutritional and lung status of the individual in efficacy control of oropharyngeal dysphagia.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100010&lng=en&tlng=en

39

scielo_articles/scl/1516-1846/S1516-18462010000100010.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Silva, Roberta Gonçalves da", "Jorge, Adriana Gomes", "Peres, Fernanda Matias", "Cola, Paula Cristina", "Gatto, Ana Rita", "Spadotto, André Augusto" ]

null

[ "Transtornos de Deglutição", "Reabilitação", "Eficácia" ]

null

[ "Deglutition Disorders", "Rehabilitation", "Efficacy" ]

null

[ "Universidade de São Paulo", "Universidade Estadual Paulista", "Hospital Estadual Bauru", "Universidade Estadual Paulista", "Universidade Estadual Paulista", "Hospital Estadual Bauru" ]

scl/1516-1846/S1516-18462010000100009.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462010000100009

10.1590/S1516-18462009005000058

REHABILITATION

Clínica Ortho-Face

Medidas orofaciais em adolescentes do estado do Rio de Janeiro segundo a tipologia facial

null

Orofacial measurements in teenagers from Rio de Janeiro State according to facial typology

Guedes, Sheila Pereira de Castro

2,010

2

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: verificar se há diferença entre as medidas orofaciais segundo o tipo facial. MÉTODOS: 39 adolescentes leucodermas entre 15 e 17 anos, de ambos os sexos, com dentição permanente e sem queixa ou histórico de tratamento fonoaudiológico. Utilizando um paquímetro digital CE ELECTRONIC mensurou-se a altura do lábio superior, inferior e filtro, terços superior, médio e inferior da face, assim como distância entre canto externo do olho e comissura labial em ambos os lados. RESULTADOS: considerando a variável tipologia facial houve diferença para a altura do lábio superior, filtro e terços superior e inferior da face. Não se observou diferença entre os tipos faciais para as medidas de altura do lábio inferior, terço médio da face e distância do canto externo do olho à comissura labial, em ambos os lados. CONCLUSÃO: na amostra estudada, a altura de lábio superior foi maior no dolicofacial que no mesofacial, a altura do filtro foi maior no dolicofacial que no braquifacial, o terço superior da face foi maior no mesofacial que nos demais tipos e o terço inferior foi maior no dolicofacial que no braquifacial.

null

PURPOSE: to check if there is any difference among the orofacial measurements, according to the facial typology. METHODS: 39 leukoderm teenagers, aged between 15 -17-year old of both genders, with permanent dentition and with no history of speech and swallowing disorders or treatment. Using a digital instrument (CE ELECTRONIC), measures we carried out concerning length of the upper and lower lip and philtrum, thirds of the face as well of the sides of the face measures. RESULTS: considering the facial topology variable, there was a difference as for the length of the upper lip and philtrum and superior and inferior thirds of the face according to the facial type. We did not observe difference among the facial types as for the length of the lower lip and middle thirds of the face and the measures on both sides of the face. CONCLUSION: in the studied sample, the length of upper lip was bigger in the long face than in the medium face, the length of the philtrum was bigger in the long face than in the short face, the superior thirds of the face was bigger in the medium face than in the others types and inferior thirds was bigger in the long face than in the short face.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462010000100009&lng=en&tlng=en

16

scielo_articles/scl/1516-1846/S1516-18462010000100009.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Guedes, Sheila Pereira de Castro", "Teixeira, Bárbara Veiga", "Cattoni, Débora Martins" ]

null

[ "Face", "Antropometria", "Medidas", "Adolescente", "Circunferência Craniana", "Morfologia" ]

null

[ "Face", "Anthropometry", "Measures", "Adolescent", "Cephalometry", "Morphology" ]

null

[ "Clínica Ortho-Face", "Clínica Odontológica Integrada Ltda", "Centro de Especialização em Fonoaudiologia Clínica", "Clínica Odonto", "Prefeitura Municipal de Armação dos Búzios", "Clínica Médica Santa Maria" ]

scl/1516-1846/S1516-18462009000800016.xml

pt

research-article

Revista CEFAC

1982-0216

SciELO Brazil

ABRAMO Associação Brasileira de Motricidade Orofacial

S1516-18462009000800016

10.1590/S1516-18462009000800016

REHABILITATION

Universidade Federal de Santa Maria

Estudo da equivalência entre as listas de sentenças em Português

null

Study of equivalence among the lists of sentences in Portuguese

Santos, Sinéia Neujahr dos

2,009

12

null

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

OBJETIVO: verificar a equivalência entre as listas de sentenças do teste Listas de Sentenças em Português, proposto por Costa em 1998. MÉTODOS: as informações foram retiradas de um banco de dados de um projeto de pesquisa. Foram selecionados 240 indivíduos que possuíam no mínimo o ensino médio completo, com idade entre 18 e 30 anos e apresentarem limiares de audibilidade dentro da normalidade. Os Limiares de Reconhecimento de Sentenças no Silêncio e no Ruído foram pesquisados em cada orelha separadamente através de fones auriculares. No Limiar de Reconhecimento de Sentenças no Ruído, fala e ruído foram apresentadas ipsilateralmente. RESULTADOS: ao comparar os resultados encontrados entre as listas, obteve-se uma diferença média de 0,03 dB NA a 0,86 dB NA no silêncio e de 0,04 dB NA a 1,06 dB NA no ruído. Observou-se também que os valores mínimos e máximos nas seis listas foram muito próximos. CONCLUSÃO: observou-se que na aplicação do teste Listas de Sentenças em Português, através de fones auriculares, tanto no silêncio como no ruído, foram obtidos resultados similares nas listas 1B, 2B, 3B, 4B, 5B e 6B, mostrando haver equivalência entre as listas.

null

PURPOSE: to investigate the equivalence among of sentence lists of the test: Lists of Sentences, in Portuguese, proposed by Costa in 1998. METHODS: the information was taken from a database of a research project. 240 individuals with at least complete high-school, 18 to 30-year old and having normal audibility thresholds, were studied. The Sentence Recognition Thresholds under Silence and under Noise were separately searched in each ear through earphones. In The Sentence Recognition Thresholds under the Noise, speech and noise were presented at the same ear. RESULTS: comparing the results among the lists, we find average difference of 0.03 dB NA to 0.86 dB NA under silence and 0.04 dB NA to 1.06 dB NA under noise. The minimum and maximum values in the six lists were very close. CONCLUSION: it was observed that in the application of the test Lists of Sentences in Portuguese, through earphones, both under silence as well as under noise, similar results were obtained in the lists 1B, 2B, 3B, 4B, 5B and 6B, showing equivalence among the lists.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-18462009000800016&lng=en&tlng=en

18

scielo_articles/scl/1516-1846/S1516-18462009000800016.xml

scielo.br

scl

[ "REHABILITATION" ]

[ "Santos, Sinéia Neujahr dos", "Daniel, Raquel Cristina", "Costa, Maristela Julio" ]

null

[ "Audiologia", "Testes de Discriminação da Fala", "Percepção Auditiva" ]

null

[ "Audiology", "Speech Discrimination Tests", "Auditory Perception" ]

null

[ "Universidade Federal de Santa Maria", "Clínica Valéria Colomé" ]

scl/1516-1439/S1516-14392022000100302.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100302

10.1590/1980-5373-mr-2021-0495

ENGINEERING, CHEMICAL

Sofia University “St.Kliment Ohridski”

null

Study of Mechanical Stresses in Thin-Walled Pressure Vessels Using Ultrasonic Methods

Ivanova, Yonka

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

This paper presents an experimental study of the propagation of ultrasonic Rayleigh waves in the walls of a pressure vessel in order to estimate mechanical stresses. The ability to assess stresses using ultrasonic methods is based on the acoustoelastic effect, ie. the change of velocity of propagation of the ultrasonic Rayleigh waves (URW) in stressed media. The experiments were carried out using a hydraulic test conducted in a pressure vessel. Measurements of the travel time of the URW over the walls of the vessel in the axial and circumferential direction were carried out with a pressure change of up to 7 MPa at a constant temperature. Relations between the relative changes in the travel time of waves and the change in pressure were found. The influence of temperature and thermal stresses on the velocities of ultrasonic waves was not taken account. The conducted experiments confirmed the finding that the difference in the relative changes in the travel time of URW in circumferential and axial directions changes linearly with the change in the pressure in the vessel.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100302&lng=en&tlng=en

32

scielo_articles/scl/1516-1439/S1516-14392022000100302.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Ivanova, Yonka" ]

null

[ "thin-walled pressure vessel", "biaxial stress state", "ultrasonic Rayleigh waves", "acoustoelastic effect", "Momentless Shell theory" ]

null

[ "Sofia University “St.Kliment Ohridski”", "Institute of Mechanics at Bulgarian Academy of Sciences" ]

scl/1516-1439/S1516-14392022000100301.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100301

10.1590/1980-5373-mr-2021-0491

ENGINEERING, CHEMICAL

Universidade Federal de Lavras

null

Pressing Temperature Effect on the Properties of Medium Density Particleboard Made with Sugarcane Bagasse and Plastic Bags

Nogueira, Nayra Diniz

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

The objective of this work was to evaluate the effects of different pressing temperatures on the physical and mechanical properties of Medium Density Particleboard (MDP) manufactured with sugarcane bagasse and waste plastic bags.The temperatures of 160, 180, 200 and 220ºC were evaluated for the panels pressing. The panels were produced with a nominal density of 0.70 g/cm3, a face/core ratio of 40:60, 12% urea-formaldehyde adhesive for the faces and 8% for the core. The panels were evaluated for properties of density, compaction ratio, humidity, water absorption after two and twenty-four hours (WA2h and WA24h), thickness swelling after 2 and 24 hours of immersion in water (TS2h and TS24h), module of rupture (MOR) and module of elasticity (MOE) in static bending, internal bonding, janka hardness and screw pulling. There was no significant effect of pressing temperature on density, MOR, MOE, internal bonding and janka hardness of the panels.The pressing temperature significantly influenced the properties of WA, TS and screw pullout, promoting a decrease in the mean values of WA2h, WA24h, TS2h and TS, and an increase in screw pullout resistance. The temperature of 220°C resulted in MDP panels with sugarcane bagasse and residual plastic bags of better quality.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100301&lng=en&tlng=en

50

scielo_articles/scl/1516-1439/S1516-14392022000100301.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Nogueira, Nayra Diniz", "Narciso, Carolina Rezende Pinto", "Felix, Adriele de Lima", "Mendes, Rafael Farinassi" ]

null

[ "Agroindustrial residues", "particleboard", "plastic residues", "sustainability", "reuse", "sugarcane bagasse" ]

null

[ "Universidade Federal de Lavras" ]

scl/1516-1439/S1516-14392022000100300.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100300

10.1590/1980-5373-mr-2021-0463

ENGINEERING, CHEMICAL

Grupo de Tecnologia de Fabricação Assistida por Plasma e Metalurgia do Pó

null

Kinetics of the UNS S32750 Super Duplex Stainless Steel Low-Temperature Plasma Nitriding

Lima, J. F. V.

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract This work reports an experimental investigation on the thermodynamic and kinetic view-point of the nitrided layer growth behavior, carried out separately at ferrite and austenite phase grains, for the UNS S32750 super duplex stainless steel (SDSS). For this purpose, and motivated by the DSSs distinct behavior showing formation of two- or single-phase nitrided layers, which apparently depend on the steel substrate chemical composition, two series of treatment were studied here, one varying the nitriding temperature on the 300-450 °C range for 4 h time, and other one varying the time on the 2-8 h range at 350 °C. Microstructural characterization of studied layers by means of SEM and EDS analysis, XRD and microhardness measurements showed precipitation-free nitrogen-expanded austenite layer formation on both steel phases for all samples treated up to 400 °C. The nitriding kinetics study showed that the layer thickness on both steel phases is proportional to the square root of the treatment time and follows an Arrhenius law for the studied treatment temperatures. The nitrogen diffusion activation energy, separately determined from the layer growth on each steel phase, was 115±3.2 and 120±5.4 kJmol-1, for austenite and ferrite grains, respectively.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100300&lng=en&tlng=en

61

scielo_articles/scl/1516-1439/S1516-14392022000100300.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Lima, J. F. V.", "Scheuer, C. J.", "Brunatto, S. F.", "Cardoso, R. P." ]

null

[ "UNS S32750 super duplex stainless steel", "low-temperature nitriding", "nitriding kinetics", "plasma nitriding", "nitrogen-expanded austenite" ]

null

[ "Grupo de Tecnologia de Fabricação Assistida por Plasma e Metalurgia do Pó", "Universidade Federal de Santa Maria", "Universidade Federal do Paraná", "Universidade Federal de Santa Catarina" ]

scl/1516-1439/S1516-14392022000100298.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100298

10.1590/1980-5373-mr-2021-0552

ENGINEERING, CHEMICAL

Universidad San Francisco de Quito

null

Electrodeposition of Chitosan on Ti-6Al-4V Surfaces: A Study of Process Parameters

León, Marco

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

The effect of different electrodeposition variables of chitosan coatings on Ti-6Al-4V substrates is studied. Electrolytic solutions containing chitosan at 0.1, 0.5, and 1.0 wt/v% was used to coat Ti-6Al-4V grit-blasted samples through electrodeposition, at 1.5 and 3.0 V, for 2.5, 20 and 30 min. Coating surface morphology was analyzed by scanning electron microscopy. Adhesion behavior was characterized by scratch testing, and coating stability under physiological conditions was assessed by swelling test. Electrodeposited coatings with longer times and high chitosan concentrations produced porous coatings, with a hydrogel-like structure, with better surface adhesion than those at lower concentrations and times. Swelling tests displayed a high initial swelling with posterior rapid degradation and stabilization at 3h, indicating the potential need for a crosslinking agent. These results suggest that chitosan electrodeposition has great potential for coating applications of metallic implants, and further in vitro cell assays are proposed for future studies.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100298&lng=en&tlng=en

48

scielo_articles/scl/1516-1439/S1516-14392022000100298.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "León, Marco", "Alvarez, Doménica", "Valarezo, Alfredo", "Bejarano, Lorena", "Viteri, Daniela", "Giraldo-Betancur, Astrid L.", "Muñoz-Saldaña, Juan", "Alvarez-Barreto, Jose" ]

null

[ "Bioactive coatings", "metallic implants", "electrochemical deposition", "chitosan", "hydrogel" ]

null

[ "Universidad San Francisco de Quito", "Universidad San Francisco de Quito", "Centro de Investigación y de Estudios Avanzados del IPN", "Centro de Investigación y de Estudios Avanzados del IPN" ]

scl/1516-1439/S1516-14392022000100291.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100291

10.1590/1980-5373-mr-2020-0591

ENGINEERING, CHEMICAL

Ecole Normale Supérieure de Laghouat

null

Evaluating the Corrosion Behaviour of Borided Carbon Steel C35

Kaouka, A.

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract In this work, an evaluation of corrosion resistance of boride layers formed on carbon steel C35 in different solutions of H2SO4, HCl, HNO3, NaCl and NaOH was carried out. Boriding treatment was applied on C35 carbon steel using Ekabor powder at 950 °C for 4 h. The corrosion behaviour was analyzed by the weight loss method after total immersion tests in different solutions at variable times from 24 hours to 6 months. The corrosion rate has been determined by electrochemical method using the polarization curves. Results obtained show that boriding treatment improved significantly the corrosion resistance of C35 steel in some acidic environments. The corrosion resistance of boride C35 steel is higher compared with that of untreated C35 steel, and the corrosion potentials Ecor of boride C35 steel are more electropositive than those of untreated C35 steel in some solutions.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100291&lng=en&tlng=en

31

scielo_articles/scl/1516-1439/S1516-14392022000100291.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Kaouka, A.", "Allaf, H.", "Keddam, M.", "Alaoui, O." ]

null

[ "boriding", "corrosion resistance", "weight loss method", "electrochemical method" ]

null

[ "Ecole Normale Supérieure de Laghouat", "Faculté de Génie Mécanique et Génie des Procédés" ]

scl/1516-1439/S1516-14392022000100297.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100297

10.1590/1980-5373-mr-2021-0428

ENGINEERING, CHEMICAL

Universidade Federal de Campina Grande

null

Dielectric Properties of Steatite Ceramics Produced from Talc and Kaolin Wastes

Araujo, Eliandra Dantas de

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

The main objective of this work was to study the use of kaolin processing wastes in the production of steatite ceramics, emphasizing mechanical strength and dielectric properties. Steatite ceramics were prepared using mixtures of talc with fine and coarse particle kaolin wastes (7.5, 10 and 12.5 wt.%) sintered at different temperatures (1200, 1250 and 1300°C). After sintering, the specimens were submitted to mineralogical and microstructural characterization. Linear shrinkage, apparent porosity, flexural strength and dielectric properties were also evaluated. Results showed the formation of the crystalline phases protoenstatite and quartz for all produced ceramics. The results verified for porosity, mechanical strength and dielectric properties proved to be suitable for the application of this material in electrical insulation.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100297&lng=en&tlng=en

39

scielo_articles/scl/1516-1439/S1516-14392022000100297.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Araujo, Eliandra Dantas de", "Silva, Karina Ruiz", "Grilo, João Paulo de Freitas", "Macedo, Daniel Araújo de", "Santana, Lisiane Navarro de Lima", "Neves, Gelmires de Araújo" ]

null

[ "Protoenstatite", "dielectric properties", "electrical insulators" ]

null

[ "Universidade Federal de Campina Grande", "Universidade de Aveiro", "Universidade Federal da Paraíba" ]

scl/1516-1439/S1516-14392022000100296.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100296

10.1590/1980-5373-mr-2021-0575

ENGINEERING, CHEMICAL

Taif University

null

Characterization of Iron Powder Produced by Reduction of Hot-Rolled Mill Scale In Hydrogen Gas

Alghtani, Abdulaziz H

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Rolled mill scale is one of the most valuable industrial waste. The produced mill-scale briquettes are reduced by hydrogen at varying temperatures. The reduction is carried out at 800°C, 900°C, and 1000 °C and lasts for 120 minutes. The reduced samples are studied by X-ray diffraction and scanning electron microscopy. The reduction of mill scale allows the new use and development of this material to obtain sponge iron that can be reused to produce iron-based powder metallurgy components. From the SEM, EDS, and XRD analysis, it is clear that as the reduction temperature increases from 800°C to 1000°C, the amount of produced iron powder also increases at constant holding time, where the amount of iron powder produced at 800oC is 94.55%, but it is 98.22% at the reduction temperature of 1000°C. The proposed reduction process allows obtaining a sponge iron powder of an irregular morphology with different crystallite sizes as measured by the Scherrer equation, where the crystallite size increased with the reduction temperature. The minimum crystallite size value is 44.45nm at the reduction temperature of 800°C, but it equals 60.1nm at 1000°C.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100296&lng=en&tlng=en

21

scielo_articles/scl/1516-1439/S1516-14392022000100296.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Alghtani, Abdulaziz H", "Alsharef, M.", "El-Aziz, Kh. Abd" ]

null

[ "Rolled mill scale", "Reduction process", "Crystallite size", "Hydrogen atmosphere", "Iron powder" ]

null

[ "Taif University", "Taif University" ]

scl/1516-1439/S1516-14392022000100295.xml

en

research-article

Materials Research

1980-5373

SciELO Brazil

ABM, ABC, ABPol

S1516-14392022000100295

10.1590/1980-5373-mr-2021-0589

ENGINEERING, CHEMICAL

Inner Mongolia University of Technology

null

Experimental Study on High-Cycle Fatigue Properties of Q420C Steel at Room Temperature

Yang, Liguo

2,022

null

This work is licensed under a Creative Commons Attribution 4.0 International License.

null

Abstract Q420 structural steel, which is widely used in transmission towers and offshore platform structures, has been studied less than other steels. However, fatigue failure of offshore platform structures can occur under repeated wave loads. The fatigue strength applied stress–number of cycles (S-N) curves of Q420C structural steel were obtained by performing static tensile tests and high-cycle fatigue tests, and the fatigue crack formation and development were investigated based on the fracture morphology. The steel fatigue lifetimes were compared with standard curves and those of steels with various strengths reported previously. The results showed that the fatigue failure of the specimen was typical, and the fracture surface could be divided into a crack initiation region, a propagation region, and a transient fracture region. The Q420C curve was above the BS7608:2014, GB50017-2017, and ANSI/AISC360-10 standard curves. The S-N curve specified in the standard is conservative for Q420C steel. The strength of the steel directly affected its fatigue properties, and the thickness of the steel plate had a significant effect on the fatigue properties.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392022000100295&lng=en&tlng=en

25

scielo_articles/scl/1516-1439/S1516-14392022000100295.xml

scielo.br

scl

[ "ENGINEERING, CHEMICAL", "MATERIALS SCIENCE, MULTIDISCIPLINARY", "METALLURGY & METALLURGICAL ENGINEERING" ]

[ "Yang, Liguo", "Xing, Yongming" ]

null

[ "High-cycle fatigue", "fatigue strength", "fatigue damage", "S-N curve" ]

null

[ "Inner Mongolia University of Technology", "Inner Mongolia University of Technology" ]