Pesquisa | SciELO

Abstract Objective To evaluate the impact of the race (Black versus non-Black) on maternal and perinatal outcomes of pregnant women with COVID-19 in Brazil. Methods This is a subanalysis of REBRACO, a Brazilian multicenter cohort study designed to evaluate the impact of COVID-19 on pregnant women. From February2020 until February 2021, 15 maternity hospitals in Brazil collected data on women with respiratory symptoms. We selected all women with a positive test for COVID-19; then, we divided them into two groups: Black and non-Black women. Finally, we compared, between groups, sociodemographic, maternal, and perinatal outcomes. We obtained the frequency of events in each group and compared them using X2 test; p-values < 0.05 were considered significant. We also estimated the odds ratio (OR) and confidence intervals (CI). Results 729 symptomatic women were included in the study; of those, 285 were positive for COVID-19, 120 (42.1%) were Black, and 165 (57.9%) were non-Black. Black women had worse education (p = 0.037). The timing of access to the health system was similar between both groups, with 26.3% being included with seven or more days of symptoms. Severe acute respiratory syndrome (OR 2.22 CI 1.17–4.21), intensive care unit admission (OR 2.00 CI 1.07–3.74), and desaturation at admission (OR 3.72 CI 1.41–9.84) were more likely to occur among Black women. Maternal death was higher among Black women (7.8% vs. 2.6%, p = 0.048). Perinatal outcomes were similar between both groups. Conclusion Brazilian Black women were more likely to die due to the consequences of COVID-19.

Resumo Objetivo Avaliar o impacto da raça (negra versus não negra) nos desfechos maternos e perinatais de gestantes com COVID-19 no Brasil. Métodos Esta é uma subanálise da REBRACO, um estudo de coorte multicêntrico brasileiro desenhado para avaliar o impacto da COVID-19 em mulheres grávidas. De fevereiro de 2020 a fevereiro de 2021, 15 maternidades do Brasil coletaram dados de mulheres com sintomas respiratórios. Selecionamos todas as mulheres com teste positivo para COVID-19; em seguida, as dividimos em dois grupos: mulheres negras e não negras. Finalmente, comparamos, entre os grupos, os resultados sociodemográficos, maternos e perinatais. Obtivemos a frequência dos eventos em cada grupo e comparamos usando o teste X2; Valores de p <0,05 foram considerados significativos. Também estimamos o odds ratio (OR) e os intervalos de confiança (IC). Resultados 729 mulheres sintomáticas foram incluídas no estudo; desses, 285 foram positivos para COVID-19, 120 (42,1%) eram negros e 165 (57,9%) não eram negros. As mulheres negras apresentaram pior escolaridade (p = 0,037). O tempo de acesso ao sistema de saúde foi semelhante entre os dois grupos, com 26,3% incluídos com sete ou mais dias de sintomas. Síndrome respiratória aguda grave (OR 2,22 CI 1,17–4,21), admissão em unidade de terapia intensiva (OR 2,00 CI 1,07–3,74) e dessaturação na admissão (OR 3,72 CI 1,41–9,84) foram mais prováveis de ocorrer entre mulheres negras. A mortalidade materna foi maior entre as negras (7,8% vs. 2,6%, p = 0,048). Os resultados perinatais foram semelhantes entre os dois grupos. Conclusão Mulheres negras brasileiras tiveram maior probabilidade de morrer devido às consequências da COVID-19.

https://doi.org/10.1055/s-0043-1770133

Improvement of the properties of hardboard with heat treatment application
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Costa, Laíze Jorge da

; Paula, Edgley Alves de Oliveira

; Melo, Rafael Rodolfo de

; Scatolino, Mario Vanoli

; Albuquerque, Felipe Bento de

; Oliveira, Ramona Rodrigues Amaro de

; Souza, Joana Alice Galdino de

; Silva, Ana Karla Vieira da

; Santos, Márcia Ellen Chagas dos

; Rodolfo Junior, Francisco

Matéria (Rio de Janeiro)

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2023, Volume 28 Nº 1 elocation e20220291

Resumo: En | Texto: En | PDF: En

ABSTRACT The attempt to face the limitations of wood-based materials, especially concerning the relationship with water, is still a considerable gap in research on this subject. The present work proposes the accomplishment of thermal treatment in fiberboard-type hardboard, using different temperatures and times, to evaluate the effect on the physical-mechanical properties. The parameters of the heat treatment were temperatures of 120 and 160 °C and times of 20 and 40 min. The hardboards were individually heat treated in a kiln. The characterization was performed from physical tests such as bulk density, moisture content, water absorption (2 and 24 h), thickness swelling (2 and 24 h); and mechanical properties of flexural strength. The treatment with a temperature of 160 °C for 40 min showed the lowest values of water absorption in 24 h (34%). Thickness swelling was lower compared to control, for all the treatments applied. Regarding flexural strength, the treatment that adopted the 160 °C for 20 min showed the highest MOR value (26.3 MPa). In general, the performance of heat treatments positively influenced the physical and mechanical properties of the hardboards, being an interesting alternative in the development of products for applications in internal environments.

https://doi.org/10.1590/1517-7076-rmat-2022-0291

Durability and resistance of eco-friendly particleboards produced from agroforestry residues
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Mensah, Prosper

; Govina, James

; Owusu-Asante, Judith Odei

; Seidu, Haruna

; Rodolfo Junior, Francisco

; Paula, Edgley Alves de Oliviera

; Pedrosa, Talita Dantas

; Melo, Rafael Rodolfo de

Matéria (Rio de Janeiro)

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2023, Volume 28 Nº 2 elocation e20230027

Resumo: En | Texto: En | PDF: En

Abstract The aim to evaluate the raw material (agroforestry residues) for particleboard manufacture from the: pseudostem of Musa paradisiaca; the stem and pods of Theobroma cacao; and the sawdust of Ceiba pentandra. The particleboards produced from these cellulosic residues are mixed with cassava starch’s natural adhesive and urea formaldehyde’s synthetic adhesive. The results indicate that lignin, α-cellulose, hemicellulose, and extractives ranged from 6.2–19.0%, 41.4–50.2%, 24.4–31.5%, and 6.8–18.8% respectively and they were significantly different from each other. Additionally, tannins, alkaloids, saponins, flavonoids, phenols, glycosides, and sterols were the phytochemicals present in biomass materials in different quantities. Also, carbon, oxygen, nitrogen, and boron were the elementals significantly present in the manufactured particleboards in the range of 35.3–52.8, 30.2–43.0, 4.2–24.0, and 3.2–9.9 percentage concentration respectively. As for the mechanical properties, it was verified that the cellulose content influenced 96.5% of the variability of the modulus of rupture (MOR) values. Understanding the distribution, functional properties, and impact of biomass organic, phytochemicals and elemental constitutions is an impetus to the improvement of processes with higher retention of these constitutions in the utilization of agroforest residues in the particleboard industry. These chemical compositions of the residues under study contributed largely to the characteristics of the manufactured particleboards.

https://doi.org/10.1590/1517-7076-rmat-2023-0027

From coconut waste to the production of cementitious composites as an alternative for civil construction
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Silva, Fernanda Monique da

; Scatolino, Mario Vanoli

; Paula, Edgley Alves de Oliveira

; Almeida, Vanessa Gentil de Oliveira

; Albuquerque, Felipe Bento de

; Vieira, Ricardo Alan da Silva

; Souza, Joalis Barbalho de

; Pedrosa, Talita Dantas

; Rodolfo Junior, Francisco

; Melo, Rafael Rodolfo de

Matéria (Rio de Janeiro)

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2023, Volume 28 Nº 3 elocation e20220146

Resumo: En | Texto: En | PDF: En

ABSTRACT Economic development based on cleaner industrial technologies has been increasingly studied in recent years. Cementitious composites reinforced with lignocellulosic fibers can be a sustainable alternative for use in engineering. The study aimed to evaluate the technological properties of cementitious composites produced from natural and industrial coconut fiber to compare the reinforcement with wood particles. Physical tests (density, water absorption, and thickness swelling) and mechanical tests (static bending) were carried out in four treatments, which varied the fiber and cement contents. It was found that treatment with natural coconut fiber had the lowest density value, 0.59 g/cm3, and treatment with industrial coconut fiber had the lowest water absorption value for the times and times of 2 and 24 h, 0.19, and 0.38%, respectively, and the treatment with wood particles, the highest values of modulus of elasticity and rupture, 1,897 MPa and 2.44 MPa. The study of the use of lignocellulosic materials as protection in cementitious composites is essential for applications in building constructions to reduce the environmental impacts generated by the generation of waste and use of non-renewable materials and to promote sustainable development.

https://doi.org/10.1590/1517-7076-rmat-2023-0146

Initial evaluation in the climacteric
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Baccaro, Luiz Francisco Cintra

; Paiva, Lúcia Helena Simões da Costa

; Nasser, Elizabeth Jeha

; Valadares, Ana Lúcia Ribeiro

; Silva, Célia Regina da

; Nahas, Eliana Aguiar Petri

; Kulak Junior, Jaime

; Rodrigues, Márcio Alexandre Hipólito

; Albernaz, Marco Aurélio

; Wender, Maria Celeste Osório

; Mendes, Maria Célia

; Dardes, Rita de Cassia de Maio

; Strufaldi, Rodolfo

; Bocardo, Rogerio Cesar

; Pompei, Luciano de Melo

Revista Brasileira de Ginecologia e Obstetrícia

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Mai 2022, Volume 44 Nº 5 Páginas 548 - 556

Resumo: En | Texto: En | PDF: En

https://doi.org/10.1055/s-0042-1750282

Genitourinary Syndrome of Menopause
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Valadares, Ana Lúcia Ribeiro

; Kulak Junior, Jaime

; Paiva, Lúcia Helena Simões da Costa

; Nasser, Elizabeth Jeha

; Silva, Célia Regina da

; Nahas, Eliana Aguiar Petri

; Baccaro, Luiz Francisco Cintra

; Rodrigues, Márcio Alexandre Hipólito

; Albernaz, Marco Aurélio

; Wender, Maria Celeste Osório

; Mendes, Maria Célia

; Dardes, Rita de Cassia de Maio

; Strufaldi, Rodolfo

; Bocardo, Rogerio Cesar

; Pompei, Luciano de Melo

Revista Brasileira de Ginecologia e Obstetrícia

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Mar 2022, Volume 44 Nº 3 Páginas 319 - 324

Resumo: En | Texto: En | PDF: En

https://doi.org/10.1055/s-0042-1748463

Effect of thermal treatment on the physical properties of GG100 clone Eucalyptus wood
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Batista, Felipe Gomes

; Medeiro, Dayane Targino de

; Mascarenhas, Adriano Reis Prazeres

; Mendes, Lourival Marin

; Silva, Danilo Wisky

; Farias, Daniel Tavares de

; Pimenta, Alexandre Santos

; Rodolfo Junior, Francisco

; Paula, Edgley Alves de Oliveira

; Melo, Rafael Rodolfo de

Matéria (Rio de Janeiro)

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2022, Volume 27 Nº 3 elocation e20220106

Resumo: En | Texto: En | PDF: En

ABSTRACT Thermal treatment can modify undesirable characteristics of some woods, dimensional instability, and excessive water adsorption. The present research work aimed to assess the effect of thermal treatment on the physical properties of clone GG100 Eucalyptus wood. Wood samples were obtained from 9 year-old trees. Samples were subjected to three types of thermal treatment (T1, T2, and T3). In T1, the wood was kept in a laboratory kiln at 100 °C for 180 min. In T2, hydrothermal treatment was performed in an autoclave at 120 °C for 120 min. In T3, the combined autoclave and laboratory kiln treatments were employed. The properties evaluated were apparent density (ρa); mass loss (ML); longitudinal (βl), radial (βr), tangential (βt), and volumetric shrinkage (βv); anisotropic factor; and equilibrium moisture content. The treatments caused a decrease of ρa and increase of ML. The Equilibrium Moisture Content (EMC) was lowest for T3, and had a negative correlation with ML, βt, and ∆v. The Pearson correlation analysis indicated the results of the thermal treatments were similar, but T1 presented the lowest variation of the physical properties compared to the other treatments, giving it the best predictability for practical uses.

https://doi.org/10.1590/1517-7076-rmat-2022-0106

Consenso chileno para la atención integral de niños y adultos con fibrosis quística
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Boza C., María Lina

; Melo T., Joel

; Barja Y., Salesa

; Codner D., Ethel

; Gomolan G., Patricio

; Hernández M., Rubén

; Astorga F., Luis

; Barrientos I., Hortensia

; Bozzo H., Rodrigo

; Calderón R., Mauricio

; Cáceres V., Jeanette

; Chávez C., Eduardo

; Contreras E., Ilse

; Henríquez Y., María Teresita

; Fielbaum C., Oscar

; Jakubson S., Leticia

; Jara H., Beatriz

; Jorquera P., Pablo

; Kogan A., Ricardo

; Lezana S., Viviana

; Meyer P., Rodolfo

; Moraga M., Francisco

; Moscoso G., Gustavo

; Navarro D., Elizabeth

; Orellana F., María de los Ángeles

; Parra O., Genoveva

; Pavez A., Daniela

; Pérez O., María Eugenia

; Pinochet N., María José

; Puppo G., Homero

; Quintanilla A., Ana Isabella

; Repetto L., Gabriela

; Slaibe C., Lisset

; Soto B., Julio

; Vega M., Adriana

; Wong L., Carolina

Revista chilena de enfermedades respiratorias

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Dez 2020, Volume 36 Nº 4 Páginas 268 - 333

Resumo: En Es | Texto: En Es | PDF: En | PDF: Es

Cystic Fibrosis (CF) is the most frequent hereditary disease in whites, with a reserved prognosis. Since 2003, Chile began a comprehensive National Cystic Fibrosis Program, directed by the Respiratory Health Unit of the Ministry of Health. To date, the main results of the Program record a significantly longer survival (average 27 years) and a significant reduction in the age of diagnosis of patients admitted from 2006 onwards. Access to Chilean Explicit Health Guarantees, the implementation of neonatal screening in some regions of the country, the organization and setting up of CF-trained teams of various specialties, has contributed to improving results. Although the main manifestations are of the respiratory and digestive system, the multisystemic nature of CF makes it necessary to know the different aspects involved in its management, in order to optimize the results of the treatment and the resources invested, both in the public and private sectors. This document is a review and an update on the main aspects of the diagnosis, monitoring and treatment of the respiratory and non-respiratory manifestations of CF.

Resumen La Fibrosis Quística (FQ) es la enfermedad hereditaria de pronóstico reservado más frecuente en raza blanca. Desde el año 2003, Chile inicia un Programa Nacional de Fibrosis Quística, de carácter integral, dirigido por la Unidad de Salud Respiratoria del Ministerio de Salud. Hasta la fecha, los principales resultados del Programa registran una significativa mayor sobrevida (promedio 27 años) y una significativa reducción en la edad de diagnóstico de los pacientes ingresados desde 2006 en adelante. El acceso a la canasta GES (Garantías Explícitas en Salud), la implementación del tamizaje neonatal en algunas regiones del país, la organización y la constitución de equipos entrenados en FQ de diversas especialidades, ha contribuido a mejorar los resultados. Si bien las principales manifestaciones son del aparato respiratorio y digestivo, el carácter multisistémico de la FQ obliga a conocer los distintos aspectos involucrados en su manejo, a fin de optimizar los resultados del tratamiento y los recursos invertidos, tanto en el sector público como privado. Este documento es una revisión y actualización sobre los principales aspectos del diagnóstico, seguimiento y tratamiento de las manifestaciones respiratorias y no respiratorias de la FQ.

1383 downloads

Hylan G-F20 and galactomannan joint flares are associated to acute synovitis and release of inflammatory cytokines
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Nunes, Rodolfo de Melo

; Cunha, Pablyana Leila Rodrigues

; Pinto, Ana Carolina Matias Dinelly

; Girão, Virgínia Claudia Carneiro

; Feitosa, Judith Pessoa de Andrade

; Rocha, Francisco Airton Castro

Advances in Rheumatology

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2020, Volume 60 elocation 26

Resumo: En | Texto: En | PDF: En

Abstract Background: Injection of Hylan G-F20 (HY) into joints may provoke local flares, which mechanisms may involve reaction to protein contaminants. We have previously developed a protein-free saline-soluble galactomannan derived from guar gum (GM) that displays both analgesia and chondroprotection in experimental osteoarthritis (OA). We now demonstrate that both GM and Hylan G-F20 (HY) promote mild synovitis with cytokine release after intra-articular injection. Methods: Mice received 100 μg/25 μL GM or HY or saline into the knees. Joint pain was evaluated using von Frey test; cell influx, interleukin (IL)-1, IL-6, and CXCL-1 (pg/mL) levels were assessed in joint lavage at 6 h. Synovia were excised for histopathology. Results: Neither GM nor HY after being given into mice knee joints induced pain albeit promoting mild cell influx into joint washings as well as mild synovitis at histology, with no damage to the underlying cartilage. HY but not GM promoted IL-1 release into mice joints. Both compounds induced IL-6 and CXCL-1 release. Conclusion: Intra-articular injection of HY or GM promote acute transient synovitis whilst not provoking detectable significant joint damage. Local administration of these polysaccharides induces acute intra-articular release of inflammatory cytokines, which may account for joint flares following viscosupplementation.

https://doi.org/10.1186/s42358-020-00127-7 378 downloads

10.

Modelo conceitual aplicável a estudos sobre determinantes sociais da saúde em municípios brasileiros
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Melo, Francisco Carlos Carvalho de

; Costa, Rodolfo Ferreira Ribeiro da

; Corso, Jansen Maia Del

Saúde e Sociedade

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2020, Volume 29 Nº 2 elocation e181094

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

Resumo Os modelos conceituais de determinantes sociais da saúde (DSS) disponíveis na literatura, embora úteis para compreensão dos mecanismos que afetam os resultados do sistema de saúde sobre as condições de vida das populações, apresentam limitações quanto à sua aplicação em estudos empíricos e, consequentemente, na orientação da gestão de políticas públicas de saúde. Isso ocorre porque as categorias adotadas por esses modelos não são adequadamente representadas por indicadores ou variáveis homogêneas, sujeitas a manipulações matemáticas ou estatísticas em um sistema simples de relacionamentos. Este estudo tem por objetivo contribuir para o preenchimento dessa lacuna, ao propor um modelo conceitual de DSS passível de aplicação operacional, ou seja, de ser reproduzido em modelos matemáticos ou estatísticos, a fim de subsidiar estudos e definir estratégias de saúde pública. O esforço recorre à literatura para revisar modelos conceituais consagrados, identificar um conjunto de DSS e apresentar recomendações e critérios de escolha. Na sequência, identifica fontes de dados confiáveis que disponibilizem indicadores e variáveis dispostos em séries históricas e propõe o desenho de um modelo conceitual aplicável, cuja operacionalização requer métodos e ferramentas próprios de uma abordagem sistêmica.

Abstract The conceptual models of Social Determinants of Health (SDH) available in the literature, although useful for comprehending mechanisms that affect the results of the health system on the living conditions of the population, present limitations regarding their application in empirical studies and, consequently, in guiding public health policies. This occurs because the categories adopted by these models are not adequately represented by indicators of homogeneous variables subject to mathematical or statistical manipulations in a simple relation system. This study aims to help filling this gap by proposing an operationally applicable SDH conceptual model - reproducible as a mathematical or statistical model - to support studies and define strategies concerning public health. We resorted to the literature to review previously developed conceptual models, identifying a set of SDH and presenting recommendations and choice criteria. Then we located reliable data sources supplying indicators and variables listed in historic series and proposed an applicable conceptual model, which requires specific methods and tools for a systemic approach for operationalization.

https://doi.org/10.1590/s0104-12902020181094 1230 downloads

11.

Modelo conceitual aplicável a estudos sobre determinantes sociais da saúde em municípios brasileiros
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Melo, Francisco Carlos Carvalho de

; Costa, Rodolfo Ferreira Ribeiro da

; Corso, Jansen Maia Del

Saúde e Sociedade

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2020, Volume 29 Nº 2 elocation e181094

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

https://doi.org/10.1590/s0104-12902020181094

12.

Lumber Yield of Four Native Forest Species of the Amazon Region
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Melo, Rafael Rodolfo de

; Dacroce, Jessyca Mayra Fruett

; Rodolfo Junior, Francisco

; Lisboa, Gerson dos Santos

; França, Luciano Cavalcante de Jesus

Floresta e Ambiente

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2019, Volume 26 Nº 1 elocation e20160311

Resumo: En | Texto: En | PDF: En

ABSTRACT The objective of this study was to evaluate the volumetric lumber yield of four native species of the Amazon Region: Cedrinho (Erisma uncinatum Warm), Cumaru ( Dipteryx odorata Aublet), Garapeira (Apuleia leiocarpa Voguel), and Cambará (Qualea paraensis Ducke). Twelve logs of each species with different diameters were randomly selected from different sawmills in northern Mato Grosso state, Brazil. Additionally, the influence of diameter on the yield of each species was evaluated through regression analysis. Among the evaluated species, Cedrinho obtained the highest yield values, followed by Garapeira. Cumaru and Cambará showed the lowest yields, and did not differ statistically. Log diameter negatively influenced lumber yield, except for Cumaru wood, which did not present a clear relation between these parameters.

https://doi.org/10.1590/2179-8087.031116 709 downloads

13.

PROPERTIES OF PARTICLEBOARDS SUBMITTED TO HEAT TREATMENTS
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Melo, Rafael Rodolfo de

; Muhl, Monalisa

; Stangerlin, Diego Martins

; Alfenas, Rafael Ferreira

; Rodolfo Junior, Francisco

Ciência Florestal

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Jun 2018, Volume 28 Nº 2 Páginas 776 - 783

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

RESUMO Os painéis aglomerados são os mais consumidos no mundo, sendo que grande parte da demanda destes painéis está associada ao setor moveleiro. O presente estudo teve como objetivo avaliar o efeito do tratamento térmico em painéis aglomerados. O experimento consistiu de quatro tratamentos mais a testemunha, avaliando as temperaturas de 160 e 180°C por períodos de seis e doze minutos. Foram utilizados painéis aglomerados comerciais produzidos com partículas de Eucalyptus sp. e, resina sintética ureia-formaldeído. Destes painéis foram retiradas amostras para os ensaios físicos (absorção de água e inchamento em espessura) e mecânicos (resistência à flexão estática e resistência ao arrancamento de parafuso). Para as propriedades físicas, os tratamentos térmicos avaliados influenciaram significativamente a absorção de água dos painéis após 24 horas de imersão. O tratamento que utilizou a temperatura de 180°C por seis minutos foi o que proporcionou o melhor desempenho. Já para as propriedades mecânicas, os tratamentos avaliados não influenciaram significativamente a resistência dos painéis.

ABSTRACT The particleboards are the most consumed in the world, where much of the demand is associated to furniture sector. This study aims to assess the heat treatment effect on particleboard panels. The experiment consisted of four treatments and the control sample, evaluating temperatures of 160°C and 180°C for six and twelve minutes. Commercial particleboard panels were produced with particles of Eucalyptus sp. and urea-formaldehyde synthetic resin. Samples for physical testing (water absorption, and thickness swelling) and mechanical (static bending strength and screw withdrawal strength) were taken from these panels. For physical properties, the assessed heat treatments influenced significantly the water absorption of the panels after 24 hours of immersion. The treatment that utilized temperature of 180°C for six minutes provided the best performance. Concerning to the mechanical properties, the evaluated treatments had non-significantly influence in the panels strength.

https://doi.org/10.5902/1980509832109 433 downloads

14.

Synthesis of MgAl2O4 by Gelatin Method: Effect of Temperature and Time of Calcination in Crystalline Structure
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Figueredo, Gilvan Pereira de

; Carvalho, Alexandre Fontes Melo de

; Medeiros, Rodolfo Luiz Bezerra de Araújo

; Silva, Francisco Marcelo

; Macêdo, Heloísa Pimenta de

; Melo, Marcus Antônio de Freitas

; Melo, Dulce Maria de Araújo

Materials Research

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2017, Volume 20 Páginas 254 - 259

Resumo: En | Texto: En | PDF: En

Magnesium aluminate can be obtained by the methods: ceramic method, sol-gel, co-precipitation, hydrothermal and combustion. However, this work presents a simple and low cost route to obtain MgAl2O4 through the gelatin method. The main objective was to use gelatin as an organic precursor and to verify the influence of temperature and time of calcination on the structural and morphological properties of obtained materials. Al and Mg nitrates were used as metal precursors with Al/Mg = 2 ratio. Samples were calcined as follows: 700 ºC, 900 ºC and 1100 ºC during 2 and 4 h. The powders were characterized by TGA, XRD and SEM. A single phase material with a crystallinity of 39.18 - 90.40% and crystallite size in the range of 12.4 to 55.5 nm was obtained. The materials exhibited morphology in the form of plates and small agglomerates. It was found that increasing temperature and time of calcination favored the growth of crystallites and increased crystallinity.

https://doi.org/10.1590/1980-5373-mr-2017-0105 1572 downloads

15.

Rotary peeling yield of Schizolobium amazonicum (Leguminosae - Caesalpinioideae)
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Melo, Rafael Rodolfo de

; Del Menezzi, Cláudio Henrique Soares

; Pavan, Bruno Ettore

; Rodolfo Júnior, Francisco

Acta Amazonica

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Set 2014, Volume 44 Nº 3 Páginas 315 - 320

Resumo: Pt En | Texto: Pt En | PDF: Pt | PDF: En

O paricá (Schizolobium amazonicum) é uma espécie nativa da floresta amazônica, que ocorre naturalmente no Brasil, Peru e Colômbia. O objetivo do presente trabalho foi avaliar o rendimento em laminação da madeira de paricá. Para isso foram avaliadas toras da espécie em uma fábrica de compensado instalada na região Amazônica brasileira. Os resultados indicaram que o paricá apresenta um elevado rendimento em laminação, sendo similar ou em alguns casos até superior a espécies tradicionalmente utilizadas para esta finalidade no Brasil, como as dos gêneros Pinus e Eucalyptus. Observou-se ainda que o rendimento em laminação da espécie pode ser estimado por meio dos parâmetros dendrométricos das toras.

The tropical tree Schizolobium amazonicum is native from the Amazonian forest, naturally occurring in Brazil, Peru and Colombia. This work aimed to study the veneer yield made from this species. For this purpose, 50 logs from S. amazonicum were rotary peeled in a plywood industry installed in Brazilian Amazon region. The results indicated that S. amazonicum had a peeling yield similar or even higher than those usually obtained for species traditionally used for this purpose in Brazil, like those of Pinus and Eucalyptus. It was also observed that the dendrometric parameters of the log can be used to estimate the peeling yield in this species.

https://doi.org/10.1590/1809-4392201302926 3093 downloads Citado 1 vez em SciELO

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