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RESUMO A Termorretificação é um método que se utiliza visando incrementar as propriedades físicas, químicas e mecânicas da madeira, expondo amostras a temperaturas elevadas. No presente estudo, avaliaram-se as melhorias e implicações proporcionadas pela termorretificação nas espécies amazônicas Angelim Vermelho, Cedro, Quaruba e Muiracatiara, quanto às alterações nas propriedades físicas, alterações na coloração, possíveis trincas, além disso, foi realizada a identificação anatômica destas espécies. A termorretificação foi realizada a temperaturas de 130, 150 e 170 °C. As maiores alterações na coloração foram evidenciadas nas espécies Angelim Vermelho e Muiracatiara. O aparecimento de trincas foi observado, principalmente, a 170 °C. A perda de massa foi diretamente proporcional ao emprego de maiores temperaturas. Alterações na densidade da madeira foram verificadas após o processo de termorretificação, com destaque para o Angelim Vermelho, seguindo um padrão linear com redução da densidade de acordo com o aumento das temperaturas aplicadas. Os ensaios da variação volumétrica revelaram uma redução da higroscopicidade das espécies tratadas em relação às testemunhas, exceto para o tratamento do Angelim Vermelho a 130 ºC. A análise anatômica possibilitou a identificação até nível de espécie, sendo as espécies estudadas: Dinizia excelsa Ducke, Cedrela fissilis Vell, Astronium ulei Mattick e Vochysia maxima Ducke, para Angelim Vermelho, Cedro, Muiracatiara e Quaruba. ABSTRACT Thermal rectification is a method that is used to increase the physical, chemical and mechanical properties of the wood, exposing samples to high temperatures. In the present study, the improvements and implications provided by thermal rectification in the Amazon species Angelim Vermelho, Cedro, Quaruba and Muiracatiara were evaluated, regarding changes in physical properties, changes in color, possible cracks, in addition to the anatomical identification of these species. Thermal rectification was carried out at temperatures of 130, 150 and 170 °C. The greatest changes in color were observed in the species Angelim Vermelho and Muiracatiara. The appearance of cracks was observed mainly at 170 °C. The loss of mass was directly proportional to the use of higher temperatures. Changes in the density of the wood were verified after the thermal rectification process, in which Angelim Vermelho stands out following a linear pattern with reduced density according to the increase in applied temperatures. The tests of the volumetric variation revealed a reduction of the hygroscopicity of the treated species in relation to the controls, except for the treatment of Angelim Vermelho at 130 ºC. The anatomical analysis allowed the identification up to species level, being the studied species: Dinizia excelsa Ducke, Cedrela fissilis Vell, Astronium ulei Mattick and Vochysia maxima Ducke, for Angelim Vermelho, Cedro, Muiracatiara and Quaruba.

Objetivo: Analisar as evidências científicas disponíveis na literatura sobre a atuação da enfermagem na assistência ao paciente em cuidados paliativos. Método: Trata-se de uma revisão integrativa. Realizou-se a busca por artigos com delimitação nos últimos 5 anos; nos idiomas português, inglês e espanhol; disponíveis na íntegra. Nas plataformas de dados: BDENF, DOAJ, LILACS, PMC, SCOPUS e Web of Science. Resultados: Os dados foram organizados e apresentados em figuras e tabelas. Dos 125 estudos encontrados, 25 estava disponível na BDENF, 46 na DOAJ, 24 na LILACS, 26 na PMC, O na SCOPUS, e 4 na Web of Science; contudo, após a leitura permaneceram apenas os que atendiam aos critérios para inclusão e exclusão descritos na metodologia, 6 estudos. Conclusão: Este estudo proporcionou a identificação de algumas dificuldades e das características associadas a atuação da enfermagem na assistência ao paciente em cuidados paliativos; vinculado ao déficit de conhecimento e falta de incentivo.

Objetivo: Evidenciar a importância da checklist de cirurgia segura na segurança do paciente dentro do centro obstétrico. Método: Trata-se de um estudo bibliográfico, tipo revisão integrativa. Realizou-se a busca por artigos; com delimitação nos últimos 5 anos; nos idiomas português, inglês e espanhol; disponí­veis na í­ntegra. Nas seguintes plataformas de dados: BDENF, LILACS, MEDLINE/BVS, SciELO, MEDLINE/PubMed, e Science Direct. Os dados foram organizados e apresentados em figuras e tabelas. Resultados: Dos 1563 estudos encontrados, 2 estava disponí­vel na BDENF, 2 na LILACS, 44 na MEDLINE/BVS, 1 na SciELO, 121 na MEDLINE/PubMed, e 1393 na Science Direct; contudo, após a leitura permaneceram apenas os que atendiam aos critérios para inclusão e exclusão descritos na metodologia, totalizando 7 estudos. Conclusão: Os resultados obtidos instigam a reflexões e discussões enquanto relevante aporte de referencial de conhecimento cientí­fico no campo da saúde e enfermagem, para o gerenciamento em segurança do paciente.

The objective of this research is to evaluate the possibility of use of tropical hardwood species (Amburana cearensis and Cedrella fissilis) for grilling plank production. Physical, chemical and organoleptic properties were evaluated and compared with properties of a well-used wood specie for grilling plank across Europe and USA, Western Red Cedar (Thuja plicata). For chemical analysis, three techniques were used: hydro distillation, soxhlet and head space. Normality test and analysis of variance (ANOVA) were used for the comparison between Thuja plicata and tropical hardwoods. The results of organoleptic, chemical and statistical analysis demonstrated the possibility of use of Amburana cearensis and Cedrella fissilis on grilling plank production, with no volatile compound present in these species being toxic, low apparent density and Nerolidol presence, chemical compound used as flavoring agent, enabling their use as grilling planks.

This paper proposes the assessment of particleboards based on the Circular Economy (CE) approach, in which wood wastes and bio-resins are used to produce circular construction materials and compare them with conventional panels made of synthetic polymers and virgin wood particles. The use of discarded wood in particleboards aims to provide circular routes for this solid waste instead of the landfill after use. In addition, two bio-based polyurethane (PU) and urea–formaldehyde (UF) polymers are compared for the production of particleboards. The alternative particleboards are made with raw wood shavings of the species Pinus taeda, Pinus elliotti and Eucalyptus urograndis, without sifting processing. The particleboards are evaluated by the screw pull-out tensile test, three-point bending test, swelling after water immersion and colourimetry. Additional analyses such as surface roughness, thermal conductivity, apparent porosity and scanning electronic microscopy are performed for the characterisation of the panels. The technical viability of particleboards is obtained by mechanical analysis for higher density composites of PU polymers and eucalyptus wood. Finally, a life cycle assessment of particleboards made from recycled wood and bio-resins reveals that all scenarios for the production of particleboards in a CE approach are environmentally benign alternatives, reducing up to 95% of the environmental impacts to human toxicity, abiotic depletion and other impacts compared to the traditional and linear scenario. The best circular scenarios are more sustainable than linear scenarios, especially for the cases of particleboards are made with medium densities involving eucalyptus or pinus wood wastes and PU polymer.

Wood-based panels have been widely used around the world in various segments of timber industry. Thus, alternative raw-materials have been systematically researched in order to reduce of wood demand in particleboard production. The aim of this work was to produce and evaluate particleboards of Eucalyptus grandis and oat hulls (Avena sativa), bonded under pressure with castor oil based polyurethane resin, in the proportion of 10% relative to the dry mass of the particles. The percentages of particles used per material were: Eucalyptus grandis 100, 85, 70 e 0% and oat hulls 0, 15, 30 e 100%, respectively. Physical-mechanical performance of the panels produced was evaluated based on standards ABNT NBR 14810:2006[1] and BS EN 312:2003[2]. By analysis of variance (ANOVA), the fraction of particles of Eucalyptus grandis was significant only in the modulus of rupture (MOR) in static bending. Panels produced with 100% oat hulls presented highest value of MOR.

This paper discusses the potential use of sugarcane bagasse in two different fiber lengths (5 mm and 8 mm) of the same density as a raw material for the production of particleboards, using castor oil-based two-component polyurethane adhesive. The quality of the product that can be manufactured industrially was evaluated based on density, thickness swell (TS), absorption (WA), modulus of elasticity (MOE), modulus of rupture (MOR) in static bending and internal bond (IB), according to the Brazilian NBR 14.810:2006 standard. The results revealed a significant difference between the particleboards made with 5-mm-long fibers and those made with 8-mm-long fibers. An analysis by scanning electron microscopy (SEM) indicates that the interparticle spaces are filled with castor oil-based two-component polyurethane adhesive, contributing to improve the physicomechanical properties of the particleboards. A durability assessment based on accelerated aging tests shows that waterproofed particleboards can be used in moist environments.

Tests simulating exposure to severe weather conditions have been relevant in seeking new applications for particleboard. This study aimed to produce particleboards with residues of CCB (chromium-copper-boron oxides) impregnated Pinus sp. and castor oil-based polyurethane resin, and to evaluate their performance before and after artificial accelerated aging. Panels were produced with different particle mass, resin content and pressing time, resulting eight treatments. Particles moisture and size distribution were determined, beyond panel physical and mechanical properties, according to NBR14810-3: 2006. After characterization, treatments B and G (small adhesive consumption and better mechanical performance, respectively) were chosen to artificial aging tests. Statistical results analysis showed best performances were achieved for waterproof aged samples, of both B and G treatments. As example, in treatment B, MOR and MOE values were 23 MPa and 2,297 MPa, samples before exposure; 26 MPa and 3,185 MPa, 32 MPa and 3,982 MPa for samples after exposure (non-sealed and sealed), respectively.

No presente trabalho, considera-se o estudo do potencial de utilização de resíduos da casca de amendoim, com o intuito de agregar valor a este material, por meio da fabricação de painéis de partículas aglomeradas com resina ureia-formaldeído, prensados à temperatura de 100 ºC. A qualidade dos painéis foi avaliada com base nas prescrições do documento normativo ASTM D 1037:2006 por meio de ensaios físico-mecânicos de densidade, inchamento em espessura, absorção de água e flexão estática. Os painéis avaliados apresentaram densidade média variando de 0,69 a 0,83 g cm-3, MOR 4,37 a 5,34 MPa e MOE 590 a 700 MPa, para painéis com e sem tratamento preservativo. É possível afirmar, baseando-se no documento normativo ANSI A208.1:1993, que o material apresenta potencial para utilização em ambientes internos, como revestimento superficial de residências, construções agrícolas, setor moveleiro e decorativo. Recomenda-se a intervenção no processo de fabricação do painel, para melhorar as propriedades mecânicas e possibilitar o uso estrutural do material. In this study, the potential use of residues of peanut husks was verified, in order to add value to these materials through the manufacture of panels of particleboards. For this procedure, it was used urea-formaldehyde resin and the panels were mechanical pressed at a temperature of 100 ºC. The quality of the panels was evaluated based on the prescriptions of the normative document ASTM D 1037:2006, through physical and mechanical tests of characteristics, such as: density, swelling in thickness, water absorption and static bending. The panels evaluated showed bulk density varying between 0,69 a 0,83 g cm-3, MOR and MOE between 4,37 - 5,34 MPa and 590 - 700 MPa respectively, for panels with and without preservative treatment. It is possible to claim, based in the normative document ANSI A208.1:1993, that the material presents a potential for use in internal areas as superficial covering of residential buildings, agricultural buildings, furniture and decorative sectors. Intervention in the board production process is recommended, in order to improve the mechanical properties of the material and enable its structural use.

As especies utilizadas na arborizacao urbana requerem periodicas podas para atender aosrequisitos peculiares das essencias e para garantir a seguranca em relacao as redes eletricase de telefonia. O grande volume de material oriundo das podas tem potencial para, naforma de particulas, ser empregado na producao de paineis para emprego na confeccaode moveis e para aplicacao como componente de edificacoes. No presente trabalho, utilizaram-se residuos de poda de arvores de Canelinha (Nectandra lanceolata), obtidos na cidadede Sao Carlos (SP). Foram produzidos paineis de madeira aglomerada, tendo comoadesivo a resina poliuretana bicomponente a base de oleo de mamona, desenvolvida noInstituo de Quimica de Sao Carlos, da USP. Os parâmetros de processo foram: particulasde dimensao maxima 2,8 mm; porcentagem de adesivo 16%; temperatura de prensagem:90oC; tempo de prensagem: dez minutos. Os ensaios para avaliacao do desempenho dospaineis produzidos foram feitos de acordo com as recomendacoes da NBR 14810:2006,da Associacao Brasileira de Normas Tecnicas. Os resultados evidenciaram a viabilidadetecnica da referida producao, pois boa parte dos requisitos normativos foi atingida. Ajustesnos parâmetros de processo, principalmente no que tange a temperatura de prensagem,serao necessarios para que os paineis atendam a todos os requisitos da NBR 14810:2006

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:21:22Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:28:21Z : No. of bitstreams: 1 2-s2.0-27844530682.pdf: 327455 bytes, checksum: 8648f36e2d4cebc4fab6d8f335055049 (MD5) Made available in DSpace on 2014-05-27T11:21:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-07-01 The compaction rate, the relation between the density of the wood panel and the density of the wood used for producing the particles, is an indicator of the product's densification. Among the various types of wood panels, particleboards are widely employed in the lumber industry, mainly for the furniture production. This paper presents a study of the relation between the compaction rate and the properties of tensile strength perpendicular to surface, Modulus of Rupture (MOR) and Modulus of Elasticity (MOE) obtained from a static bending test, thickness swelling and water absorption (2 and 24 hours). These properties were calculated according to the Brazilian ABNT, NBR 14810 standard. Particleboards were produced using the species Pinus elliotti and adhesive ureaformaldehyde. The relation was established by a multiple linear regression, and the most appropriate statistical models were determined. The estimated models indicate statistically significant effects of water absorption in 2 hours and MOR in the particleboards' compaction rate. Interunit Area of Materials Sciences and Engineering University of São Paulo, Av. Trabalhador Saocarlense, 400, Centro, 135666-590 Sao Carlos - SP São Carlos School of Engineering University of São Paulo Department of Statistics ICT Federal University of Mato Grosso - UFMT Bauru College of Engineering Paulista State University - UNESP Bauru College of Engineering Paulista State University - UNESP