988 resultados para óleo-resina de copaíba


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In the present work it was studied the behavior of four water bath curing cycles of heat activated acrylic resin considered as long duration (I – 65ºC for 30 min;50ºC for 23h and 30min; and 100º C for 1h; II- 50ºC for 24h and the rapid cycle), compared to the known long time curing cycle (9 hours for 72ºC) and short curing cycle (1 h for 65ºC; 30 min to elevate at 100º C and 1:00 to 100º C). Analysis consisted of observations and verification of the residual monomer, weight alterations, dimensional, dimensional lineal, porosity and hardness to determine material performance. The results pointed out that residual monomer presented statistical significant differences in the factor storage and interaction among the factors cycle X storage for weight alteration; statistical significant differences for the factor storage for lineal dimensional alterations, without significant differences for hardness. Porosity was verified in minimum degree in the cycle III and in appreciable amount in the cycle IV

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The aim of this study was to evaluate the effect of different carbohydrate sources associated with sunflower oil on intake, digestibility of nutrients and nitrogen balance in diets of lambs. Twenty lambs were used, assigned in a completely randomized design with a 2 x 2 factorial arrangement of treatments with two sources of neutral detergent soluble carbohydrate, starch and neutral detergent soluble fiber, with and without the inclusion of 4.2% sunflower oil. The dry matter intake was not affected by carbohydrate sources and the inclusion of oil. Diets with a high percentage of starch provided higher digestibility of dry matter, starch and ether extract. The different sources of carbohydrates had no interference on digestibility of organic matter, crude protein, neutral detergent soluble fiber, nonfiber carbohydrates, neutral detergent fiber, hemicellulose and acid detergent fiber. The addition of oil in the diets increased the digestibility of ether extract. The combination of 4.2% oil in the diet high in soluble neutral detergent fiber had no influence on the nutrient digestibility, otherwise, the addition of oil at high starch diet caused a significant reduction in the digestibility of organic matter, neutral detergent fiber, hemicellulose and nonfiber carbohydrates. The quantities of nitrogen intake, absorbed and retained, did not differ as sources of carbohydrates and oil inclusion in the diet. The association of 4.2 % sunflower oil to the different sources of carbohydrates in the diet does not affect consumption and nitrogen metabolism in lambs. The addition of 4.2 % oil in the diet with high starch (28% of DM diet) promotes reduction in digestibility of organic matter, of fibrous and nonfibrous carbohydrate in the diet.

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Products derived from wood or engineered products are becoming interesting alternatives to the replacement of solid wood in various applications, from structural components to the furniture industry and packaging. Among these products, there are panels built by strands, particles and fibers, each one having their particular characteristics and potential of use. Since the different types of panels are produced, waste generation is part of the process, and that more technological it is, it still generates losses of raw materials. Based on the need for rational use of raw materials and using almost full of industrially processed wood, It arises the proposal of this work, which seeks to use waste from the lamination, like pieces of strands, broken strands, strands rough, cracked strands to produce panels with structural characteristics of the OSL panel (Oriented Strand Lumber), LSL (Laminated Strand Lumber) and OSB (Oriented Strand Lumber). Besides the use of waste, this paper seeks an alternative to the use of the adhesive, because the industry uses formaldehyde-based adhesives, which over the press, they emit large amounts of formaldehyde, which is very aggressive to humans and environment. The panels made with polyurethane resin based on castor oil and hot-pressed were characterized by physical and mechanical tests according to specifications of European Standard (EN). High values of tensile strength, elastic modulus and density were found in the results of tests. Adding to stable values of swelling and moisture content, the panel studied adds attractive features to the panel market, especially in the civil construction

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The glassy carbon is a material with a huge technological evolution. Due to its lightness, biocompatibility and their thermal and electrical properties this material finds applications in several industrial fields such as electronics, medical, aerospace and chemical. In order to explore the conductive properties of glassy carbon for use as modified electrodes, the present work aims the processing of monolithic and reticulated glassy carbon with colloidal copper for use in electrochemical applications. First, the best parameters for the cure of furfuryl alcohol resin doped were established through viscosimetry measurements and pressurized differential scanning calorimetry. The analysis of the micrographs of the cured resins show that copper concentrations above 3% weight, generate higher porosity in the material. The characterizations of the monolithic and reticulated glassy carbon resulting from carbonization were performed by scanning electron microscopy (SEM), Raman and Electrochemical impedance spectroscopy, and although it was not possible to detect the presence of copper by SEM, the influence of these particles have been observed by Raman and FT-IR spectra and electrochemical behavior of the material. The decrease in conductivity of monolithic and reticulated glassy carbon in the presence of copper may be related to the defects caused by the presence of copper in the structure of the material.

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Sabe-se que o número de plantas com atividade comprovada no sistema nervoso central vem crescendo ultimamente, resultado do interesse renovado nesta linha de investigação. O óleo essencial da espécie Cananga odorata (Lam.) Hook. f. & Thomson possui indícios de uma potencial atividade do tipo antidepressiva. A depressão maior ou depressão unipolar é um distúrbio do sistema nervoso central com potencial para se tornar um dos maiores problemas de saúde em termos de qualidade de vida e incapacitação da população mundial em alguns anos, e os tratamentos existentes na clínica possuem diversos problemas, principalmente relacionados a efeitos colaterais. O objetivo deste projeto foi avaliar a atividade antidepressiva do óleo essencial da espécie Cananga odorata (ylang-ylang), administrado por via oral em camundongos. Foram utilizados camundongos Swiss, machos, com aproximadamente 45 dias de idade. O óleo essencial foi solubilizado em Tween, nas seguintes concentrações: 1, 10 e 100 mg/kg (administrado pela via oral – v.o.). O grupo controle negativo recebeu apenas Tween (v.o.), e o grupo controle positivo recebeu imipramina 30 mg/kg (via intraperitoneal), sempre no volume de 10 mL/kg. Os animais foram submetidos ao Teste da Suspensão pela Cauda, para avaliação da atividade do tipo antidepressiva, medindo-se o tempo total de imobilidade e a latência para o aparecimento do primeiro comportamento de imobilidade (em segundos); e ao Teste do Campo Aberto, para avaliação de atividade motora, medindo-se o número de quadrantes percorridos (indicador de ambulação espontânea), e o número de rearings (indicador de comportamento exploratório). Não foi observado efeito do tipo antidepressivo ou sobre a atividade motora e motivacional, em nenhuma das doses testadas do óleo essencial de ylang-ylang, provavelmente pela dificuldade na correlação entre a concentração administrada pela via inalatória e a dose por via oral

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The objective of this paper is the elaboration and implementation of procedures in a cartographic representation related by fundamental of thematic cartography and graphic semiology for the standardization of the Environmental Oil Spill Sensitivity Maps supported by a Geographic Information Systems (GIS) for handling and modeling of a large number of variables. These make up the Environmental Sensitivity Atlas to Oil Spills in Coastal Paulista, and that represents the phenomena that occur in geographic space accurately so as to highlight the importance of each element in the evaluation and protection of areas of greater sensitivity oil. The composition of the cartographic documents considers the Littoral Sensitivity Index (LSI), biological resources and the resources for human use that could be negatively impacted. Thus, the information contained in each map was carefully evaluated before implementation, so that the cartographic representations of various resources, environments, and other ISLs, the reader should issue an immediate message that could be understood clearly, without requiring prior knowledge of specialized. Another aspect was the distribution harmoniously all the elements contained in the document, so that information could be enough without overwhelming it. It was also taken a certain care, so each symbol could be used properly in order that there is no conflict in the information.