1000 resultados para Álcool como combustível - Variações sazonais


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Nas últimas décadas tem ocorrido um aumento expressivo da incidência de doenças fúngicas. Porém, o tratamento destas infecções pode não ser efetivo, pois os fármacos antifúngicos disponíveis causam sérios efeitos adversos, recorrência ou resistência. Algumas doenças fúngicas causam lesões cutâneas e o medicamento, geralmente administrado por via oral, dificulta a chegada do fármaco no local de ação. Adicionalmente, muitos antifúngicos tópicos não são eficazes, pois o tempo de residência no local de ação é curto e a solubilidade do fármaco nos sistemas é baixa. Uma alternativa muito explorada nos anos recentes é o desenvolvimento de sistemas de liberação de fármacos, e as microemulsões (ME) e os cristais líquidos (CL) mostraram-se promissores, pois podem aumentar o tempo de residência no local de aplicação e a solubilidade de fármacos pouco solúveis em água, como ocorre com o fluconazol (F) e o itraconazol (I). Sistemas nanoestruturados foram desenvolvidos empregando o ácido oleico (AO), álcool cetílico etoxilado 20 OE e propoxilado 5 OP (PROC) e água. Estes sistemas foram caracterizados por microscopia de luz polarizada (MLP), comportamento reológico, análise do perfil de textura (TPA), bioadesão e capacidade de incorporação dos fármacos pelos sistemas. A MLP foi utilizada na caracterização dos sistemas quanto a isotropia e anisotropia, diferenciando as ME dos CL. O comportamento reológico das ME foi Newtoniano e viscoso, e dos CL foi pseudoplástico e elástico e a temperatura não influenciou o comportamento reológico dos sistemas. As propriedades mecânicas das formulações, como dureza, compressibilidade e adesividade, foram avaliadas utilizando um analisador de textura no modo TPA. Os CL de fase hexagonal são os mais bioadesivos. As quantidades incorporadas dos fármacos nos sistemas aumentaram, principalmente comparando-se com... (Resumo completo, clicar acesso eletrônico abaixo)

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A exposição experimental a vapores de solventes pela via respiratória pode ser realizada em câmaras de dois tipos: a que expõe todo o animal por imersão na atmosfera experimental e aquela em que a exposição se dá apenas pelo nariz. O sistema para exposição apenas pelo nariz, denominado de NOES- Nose Only Exposure System, tem as vantagens de utilizar menos material, ter uma atmosfera continuamente renovada, produzir exposição mais uniforme entre os animais, ser mais facilmente controlado e evitar a penetração dos solventes por outras vias. A desvantagem está no fato na restrição do tempo do experimento por provocar estresse ao animal. O projeto experimental consistiu na validação de uma câmara de exposição para ratos, do tipo NOES, dotada de 44 portas, através da avaliação da homogeneidade e da estabilidade das concentrações de voláteis na atmosfera a ser inalada, utilizando etanol combustível como agente químico para os testes. Os resultados indicaram que a variabilidade das concentrações entre os planos da câmara (portas da camada superior e inferior), entre portas de exposição e, também, entre as médias apuradas para cada tempo não diferem expressivamente entre si. Assim, pode-se considerar que o equipamento mostrou-se adequado para manter a homogeneidade e a estabilidade das concentrações durante as 6 horas de experimentação, para o etanol combustível

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The research aimed to produce sheets of particles with waste processing of Eucalyptus sp bonded with urea-formaldehyde and evaluate the effect of pressure variation in the quality of the boards produced. To do so, the Boards made were divided into two treatments depending on the pressing pressure of 30 to 40 kgf / cm². Once pressings, climatized, the particleboards have been sectioned in test samples, and underwent physical-mechanical tests for determining density, swelling and water absorption, modulus of rupture and elasticity in static bending and internal linking. The particleboards pressed at 40 kgf / cm ² showed the best results

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This study has as objective determining the chemical properties that serve as the basis for potential scientific and technological applications of seven species of fibrous plants cultivated in Brazil, which are: Banana” (Musa spp.), “Coco” (Cocos nucifera), Curauá (Ananas erectifolius), Fique (Furcraea andina), Piteira” (Furcraea gigantea), Sisal(Agave sisalana) and “Taboa” (Typha domingensis). The tests for determining the percent dry completely, extractives soluble in cold water, in hot water, in sodium hydroxide 1% and in ethanol-toluene, and the percentages of ash, hydrophobicity, lignin, holocellulose and cellulose were performed at the Department of Environmental Sciences, Agronomy College (FCA) of UNESP – Botucatu, São Paulo State. It also presents a literature review about these fibers and their potential applications. Differences between the results obtained and those found by other authors are possibly explained by variations on the origin of plant material, the harvest season, the climate and soil where they were grown. However, the results and the methodology used, serve as a basis for further studies with natural fibers

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The internal combustion engine is a heat engine widely used in the automotive industry. In order to better understand its behavior many models in the literature have been proposed in the last years. The 0-D thermodynamic model is a fairly simple tool but it is very useful to understand the phenomenon of combustion inside the chamber of internal combustion engines. In the first phase of this work, an extensive literature review was made in order to get information about this kind of analysis and, after this, apply them in a model able to calculate the instantaneous temperature and pressure in one zone of the combustion chamber of a diesel engine. Therefore some considerations were made with the aim of increasing the accuracy of the model in predicting the correct behavior of the engine, adding the combined effects of heat transfer, leakage and injection. In the second phase, the goal was to study the internal flow of a three-dimensional model of an internal combustion engine. In order to achieve this goal the software Solidworks was used to create the geometries of an engine and the suite of softwares Ansys was used to create the moving mesh (ICEM CFD and CFX-Pre) and to solve the CFD problem (Ansys CFX code). The model was able to perform the air flow simulation during the four-stroke cycle of an engine: admission, compression, expansion and exhaust. The results obtained from both models were suitable and they open a new range of possibilities for future researches on the field

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In today's competitive environment of automakers, it is essential to obtain the highest efficiency of the production process. This paper presents a study in a pre-assembly of brake pipes and fuel of a vehicle where the value stream maps and information (VSM – Value Stream Mapping) were designed in order to improve the process by reducing the Lead Time Production of a product, reducing waste and decrease time between processes. This work can be divided into three stages, the first building the VSM of the initial state, the second VSM of the proposed state and finally the VSM than was actually performed and to present the gains were achieved effectively. The proposed VSM would lead to a gain of 54% in lead time and 61% in processing time, since the VSM implemented had gains of 47% in lead time and 48% in processing time even without major investments as originally proposed. Concluding that even without big investment, using the techniques of lean manufacturing is possible to achieve high levels of process efficiency

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This work approaches, in a simplified manner, the analysis of an aircraft’s trajectory through the 3 main flight phases, climb, cruise and descent, related to fuel consumption and elapsed time. From this analysis is developed a tool that aims optimize the flight planning operational procedure, providing an altitude that comply with fuel saving during the trip, or minimizes the trip time. The use of any altitude is an operator’s decision, that aims comply with their operational needs of each trip, getting the results provided by the tool as a primary approach to the flight profile that also bring up economics aspects of each possibility of decision to be taken. Since the aeronautical Market has singular problems, as the flight altitude optimization, there is the need to solutions very customized that many times can not attend every restriction for each operator and its related kind of operation. When we talk about executive aircrafts, is possible to note that its operators does not have enough engineering and logistic support, when compared to huge airlines companies, to analyze all exceptions of each singular operation, creating many times wastes that can be avoiding with a tool described herein in this work

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The youth has been calling attention due to the large number of social problems resulting from the risky behaviors. One of the behaviors that stand out is the use of alcohol because, besides being the first drug to be used by children and adolescents, this population begins to use increasingly early. Another behavior that is becoming concern in that particular group, also with early start, is the unprotected sex, causing problems as the unplanned pregnancy, abortions and sexually transmitted diseases. However, one factor is becoming relevant and requiring further study, the number of young women developing sexually transmitted diseases and becoming risk drinkers. In this direction, this study has as objective to discuss the high number of alcohol use among young women, the vulnerability that this use causes for the unprotected sex and the importance of these subjects teachers training. It should be noted, finally, the lack of training of teachers to work with the thematic ones, and mainly, the need to deconstruct gender stereotypes, an obstacle in preventing the use of alcohol, other drugs and sexually transmitted diseases.

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Studies have shown that adolescents begin to make use of alcoholic beverages earlier and excessively, a behavior which has several negative consequences. Thus, the present study aims at investigating whether the expectations they have for the effects of alcohol consumption are high or low and if there is a relationship between expectation and consumption pattern. AUDIT and IECPA were applied as data collection instruments. The first indentifies the pattern of alcohol use and the second investigates the expectations the subjects have in relation to the use of alcohol. The results of this study, differently than others, do not evidence the positive relationship between binge-drinking and high expectations about the use of alcohol.

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The steady increase in the price of oil and its derivatives, carbon credits, the concern with the environment combined with the precipitation of rain water and lack of water resources that Brazil has suffered in 2014 caused a migration of participation sources of energy in the Brazilian energy matrix. The hydropower sector suffered big drop at 2013 and is suffering so far, contributing thus to the generation and cogeneration of thermal energy using renewable energy sources such as: sugarcane bagasse, wood chips, rice husks, among others. The selling price of the electricity market reached the level of R$ 807, 00 MWh in January 2014 (Source: ANEEL), heating the Brazilian thermoelectric sector. Although thermoelectric use in bulk water as vaporizing fluid to produce electricity and use in various processes, water reuse plans have become an important factor in these industries. The increased use of biomass has been the bagasse which is allied to the sugarcane sector, strong market in Brazil, and consists basically use the rest of sugar cane, sugarcane industries that would play out. The sugar and ethanol industry is very unstable and only lasts for 6-8 months a year, and the remaining time in the period known as between crop that corresponds to the planting and harvesting of sugarcane and then enter the period of vintage which is the constant cane harvesting and crushing it. This instability of the market and the thermoelectric idle period leads the thermoelectric industries to seek other sources of renewable energy, such as wood chips (pine, Eucalyptus, Orange), rice husk, sorghum among others, to not be dependent on alcohol sector. The present work aims to study the use of wood chips as an alternative biomass for burning a fuel that essentially uses bagasse, the thermoelectric in question consists of two boilers that produce together 350 t / h ... (Complete Abstract click electronic access below)

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This work aims the design and analysis of a thrust frame system for a liquid fuel rocket engine. The project was developed following the design requirements established by the Division of Space Propulsion of the Institute of Aeronautics and Space. The layout of the structure was developed with the aid of a software of 3D modeling and static and dynamic analysis were performed by using a finite element package. The results of the analyzes helped in defining the layout of the structure which met all design requirements. The safety factor and the mass achieved were comfortably low, which may be useful in the future because the liquid fuel rocket engine is still in development

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Pós-graduação em Serviço Social - FCHS