841 resultados para Silicone de adição
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The increase in the oil price and the current trend of using renewable raw materials for the production of chemicals renew the interest in the production of biobutanol that, produced by fermentation of agricultural raw materials, can be used as a component of gasoline and diesel. With the commercialization of new fuels, environmental damages due to spills can occur. Among other techniques, the clean-up of these contaminated areas can be achieved with bioremediation, a technique based on the action of microorganisms, which has the advantage of turning hazardous contaminants into non toxic substances such as CO2, water and biomass. Thus, bearing in mind the use of biobutanol in the near future as a gasoline extender and due to the lack of knowledge of the effects of butanol on the biodegradation of gasoline, this work aimed to assess the aerobic biodegradation of butanol/gasoline blends and butanol/diesel (20% v/v), being the latter compared to the ethanol/gasoline blend and biodiesel/diesel (20% v/v), respectively. Two experimental techniques were employed, namely the respirometric method and the redox indicator 2,6-dichlorophenol indophenol (DCPIP) test. In the former, experiments simulating the contamination of natural environments were carried out in biometer flasks, used to measure the microbial CO2 production. The DCPIP test assessed the capability of four inocula to biodegrade the fuel blends. In butanol/gasoline experiments the addition of the alcohols to the gasoline resulted in positive synergic effects on the biodegradation of the fuels in soil and...(Complete abstract click electronic access below)
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The NbCl5 being a strong electrophile, is a potential candidate to act as a Lewis acid, and therefore it mediates various organic reactions. For this reason, it has received continuous attention by Brazilian researchers, especially in recent decades, since Brazil holds the largest reserves of niobium, besides being the largest producer of this element. The Michael addition reaction is one of the most widely used for forming carbon-carbon bonds and takes place by the addition of nucleophiles to activated olefins. Although this type of reaction is usually catalyzed by base, there are reports in the literature on the use of various Lewis acids in this type of reaction. The synthesis of enamines based acetilenodicarboxilates and amines, aromatic or alkyl, by Michael addition reaction is quite interesting, since these are valuable synthetic intermediates for the synthesis of heterocyclic and they are used in multicomponent reactions. The derivatives of anilino-fumarate also have a great potential for medical application. In this study we investigated the use of niobium pentachloride as Lewis acid to catalyze the Michael additions between the derivatives of aniline and acetilenodicarboxilates the synthesis of enamines
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Pós-graduação em Medicina Veterinária - FCAV
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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As bebidas lácteas fermentadas são produtos formulados contendo iogurte, soro de leite, polpa de frutas, além de outras matérias-primas e aditivos permitidos. O produto final deve apresentar os micro-organismos de forma viável e abundante. Sua popularidade vem aumentando significativamente, principalmente devido aos seus benefícios nutricionais, ao menor custo do produto para o fabricante, à redução do preço final para o consumidor e por apresentar baixa viscosidade, sendo consumida como bebida suave e refrescante. Apesar do processo de fabricação ser considerado simples, utilizando-se principalmente os equipamentos disponíveis nas indústrias lácteas, estes produtos podem estar sujeitos à contaminação microbiana, quando não atendidas as condições elementares de higiene e sanidade. Tal contaminação pode ser representada por leveduras, coliformes totais, termotolerantes e bolores. Considerando os aspectos mencionados, o objetivo deste trabalho foi avaliar a qualidade microbiológica de bebidas lácteas fermentadas, com adição de polpas de frutas, comercializadas na região de São José do Rio Preto û SP, por meio das seguintes análises microbiológicas: contagem de bolores e leveduras, determinação do Número Mais Provável (NMP) de coliformes totais, temotolerantes e pesquisa de Escherichia coli e de Salmonella spp. Foi ainda efetuada a determinação do pH eletrométrico. Após a obtenção dos resultados verificou-se que 20% das amostras analisadas não atenderam ao padrão microbiológico estabelecido na legislação vigente, para coliforme termotolerentes, evidenciando positividade na pesquisa de Escherichia coli, sendo por este motivo, considerados como produtos em condições sanitárias insatisfatórias, portanto, produtos impróprios para o consumo humano.(AU)
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Pós-graduação em Engenharia Civil - FEIS
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Pós-graduação em Bases Gerais da Cirurgia - FMB
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Pós-graduação em Zootecnia - FCAV
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Pós-graduação em Engenharia Civil - FEIS
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In contemporary industrial, welding processes are widely used, this is the most important process of joining metals used industrially. The welding can be used to build simple structures, like doors and gates for instance, in the same way can be used in situations of high responsibility, such as the nuclear industry and oil industry. Dissimilar welding is a case of welded joints, is characterized by the junction between different materials, for this case, stainless steel and carbon steel that are widely used in steam lines, power plants, nuclear reactors, petrochemical plants. Because their different mechanical and corrosive properties, the join, stainless steel with carbon steel, not only meets environmental requirements and also reduces cost. By using penetrating liquid tests, macrograph, hardness and tensile test was compared the possibility of replacing the current use of 309 rods as filler metal in dissimilar welding between carbon steel and stainless steel by add-on material carbon steel essentially, in this case E7018 coated electrode was used, but without the coating. After analysis of the results and for comparison, was proposed with some certainty that it is possible to replace the addition of materials, thus leading economy in this process widely used in the modern industry
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Pós-graduação em Medicina Veterinária - FCAV
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Two experiments were carried out to evaluate the effect of adding glutamine, fish oil or yeast cellular wall to the diet of weaned piglets on the expression of the enzyme ornithine decarboxylase (ODC), the protein content and DNA in small intestine samples and on performance. In the first experiment, 24 weaned piglets were used to measure the performance at the phases prestarter, starter 1 and starter 2. Four diets were tested (T1 -basal diet (BD); T2 -BD + 1% of glutamine; T3 -BD + 0,2% of yeast cellular wall; T4 -BD + 5% of fish oil). At the second experiment 45 weaned piglets were used and distributed in a randomized block design, in factorial outline with four diets and three slaughter ages (on the day of weaning, on the seventh and fourteenth days postweaning). The tested diets did not alter the piglets' performance in none of the phases. There was reduction of the expression of the ODC enzyme, of the protein concentration and of the relationship protein/DNA to the seven days postweaning, with increase of the values on the 14th day, evidencing a state of hypotrophy of the mucous membrane, suggesting that the process of protein synthesis in the small intestine was diminished in the first week after weaning, but it presented recovery signs in the second week.
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Pós-graduação em Engenharia Mecânica - FEG
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)