999 resultados para Pilhas a combustível de óxido sólido(PaCOS)


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As úlceras gástricas, além de representarem eventos patológicos comuns na clínica médica, são atualmente consideradas importantes desafios para a terapêutica, à medida que o tratamento e/ou prevenção dessa doença ainda apresentam limitações, como os efeitos adversos e a baixa qualidade de cicatrização. Outro grande problema é a difícil acessibilidade às terapias disponíveis pela população de baixa renda, devido ao seu alto custo. Considerando a problemática abordada, e levando em consideração que estudos têm mostrado que terpenóides têm apresentado atividade antiúlcera bastante significativa, propusemos investigar o efeito gastroprotetor do monoterpeno Citral em úlceras gástricas experimentais induzidas tanto por etanol quanto por antiinflamatórios não esteroidais (utilizando a Indometacina como agente indutor das ulcerações), bem como avaliar seu efeito cicatrizante. O Citral mostrou ser gastroprotetor frente ao agente lesivo etanol, a partir da dose de 25 mg/kg, em uma relação dose-dependente quando administrado oralmente, sendo mais potente do que a Carbenoxolona, utilizada como controle positivo, a partir de uma dose duas vezes menor [dose de 50 mg/kg, na qual o Citral apresentou 98 % de proteção em relação ao controle negativo (Tween 80 a 8%), contra 85 % de proteção proporcionada pela Carbenoxolona na dose de 100 mg/kg]. No entanto, no modelo de indução de úlceras gástricas por Indometacina o Citral mostrou um efeito dual, ao passo que em doses intermediárias (25 e 50 mg/kg) apresentou efeito gastroprotetor, e em doses extremas (100 e 200 mg/kg) apresentou uma significativa potencialização das lesões, permitindo assim a hipótese de um possível efeito antiinflamatório e/ou antinociceptivo nessas doses. Também foi verificado seu efeito cicatrizante na dose de 25 mg/kg, sendo tão eficaz quanto o Lansoprazol (controle positivo)... (Resumo completo, clicar acesso eletrônico abaixo)

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In this study, the drug indomethacin, a non-steroidal anti-inflammatory indoleacetic acid derivative and the complex of indomethacin and lanthanum (III) in solid form were synthesized and characterized by Thermogravimetry (TGA), Differential Thermal Analysis (DTA), Differential Scanning Calorimetry (DSC) and powder X-ray diffractometry (XRD), infrared vibrational spectroscopy by diffuse reflectance (FTIR) and complexometric titration with EDTA. With the TG curves it was possible to determine the stoichiometry of the complex as La(Ind)3·3.5H2O where Ind is the drug indomethacin. The result of thermal analyzes provided information on the thermal stability, enthalpy of dehydration and thermal behavior of the compounds. The infrared spectrum and with the aid of theoretical calculations suggests that the indomethacin is coordinated by the carboxylate group in the bidentate mode

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This Final Paper had as it main goal to make a thermoanalytical study of lighter trivalent lanthanides (Lanthanum, Cerium, Praseodymium, Neodymium, Samarium and Europium) with the Ibuprofen ligand (nonsteroidal anti-inflammatory) that have a general formula LnL3.nH2O, on solid state, where Ln are the Lanthanides, L is the Ibuprofen ligand and n = number of water molecules of hydration that went from 1,0 to all the compounds. In order to characterize this compounds, it has been used the thermoanalytical techniques TG-DTA (thermogravimetry - Diferential Thermal Analysis) and DSC (Diferential Scanning Calorimetry), Fourier transformed infrared spectroscopy (FTIR) and complexometric titration with EDTA. Through the TG-DTA technique, it has been possible to set the thermal stability of the compounds, the number of thermal decomposition steps and temperatures that ocurred that also provided stoichiometry to the synthesized compounds. The DSC technique has shown the enthalpy of dehydration of the samarium and europium compounds, it was not possible to see it in the other compounds due to a endothermic peak on the DSC curve not being formed. In the case of neodymium, a thermal event ocurred, in which it could be a oxidative decarboxylation right after the dehydration. The infrared was utilised to study the carboxilate groups streches, and so, suggest a ligand metals compound coordination, that to this present paper has been a bidentade bridged coordenation. At last, the complexometric tritation was used to very the ammount of metal present in each compound, and so, verify if the proposed stoichiometry was according to the theory

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The Sanding is a complex process involving many variables that affect the quality of the part produced, working mainly in the timber industry in the production of panels (MDF, MDP, HDF, etc...) and furniture. However, these industries use the sanding process empirically, not optimizing it. The aim of this study was to compare the behavior of sandpaper white aluminum oxide (OA-white) and Black silicon carbide (SiC-black), analyzing variables in the process as: strength, power, emission, vibration, wear particle size of sanding, and its consequences on the surface finish of the workpiece. Made the process of plane grinding samples of Pinus elliottii, processed in parallel to the fibers, which were sanded with sandpaper grain OA white and black 3-SiC abrasive conditions (new, moderately eroded and severely eroded) grain sizes in 3 (80, 100, and 120 mesh). 6 replicates was performed for each condition tested. Each trial was captured output variables of the sanding process: strength, power, emission and vibration. With two stages totaling 108 trials. After the sanded samples, it has the same surface quality by raising the surface roughness Ra. Through experiment, it can be concluded that abrasives OA-white tended to have higher strength, power, emissions and less vibration in the sanding process, compared to the SiC-black. However, surface finish exhibited similar to the particle size of 80 to 100 mesh, worn abrasive conditions. However, the particle size of 120 mesh, obtained by the roughness of sandpaper OA-bank was higher compared to SiC-black to all conditions of sandpaper due to its toughness

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Through measurements of basic parameters for determining the fluidization regime, as particle size, minimum fluidization velocity, bed porosity, etc., This paper analyze the mass distribution of the phases of the bed to be discussed in relation to: the flow gas physical properties of the solid particles and the forces acting on the solid particles circulating within the bed, as the weight force, buoyancy and drag forces (Stokes' Law). Due to the weight force is constant, open up the discussion about which of the other two forces, buoyancy and drag force, influencing the behavior of the bed. We used the photographic method to realize the statistical analyzes. Therefore, we can conclude what changes can be made more convenient in fluidizing the bed to obtain the highest efficiency for a good mixing used in industrial processes

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A formação do trombo arterial, composto predominantemente por plaquetas, se dá sob condições de estresse de cisalhamento elevado, nos locais de lesão aterosclerótica vascular e fluxo sanguíneo perturbado e tem como consequência diminuição ou obstrução do calibre dos vasos dos diferentes órgãos podendo levar a eventos isquêmicos. As doenças cardiovasculares são consideradas as principais causas de morte no mundo. Nesse contexto, estima-se que a aterosclerose/aterotrombose seja a causa primária de doença arterial coronariana e acidente vascular cerebral representado mais de 50% das causas de mortes em países ocidentais . É sabido que a aterosclerose, primeiro evento que predispõe à aterotrombose, é considerada um processo inflamatório crônico, e que a utilização de antiinflamatórios não esteroidais (AINEs) COX-1, melhor estabilizam a estrutura da placa ateromatosa impedindo o rompimento e a consequente formação do trombo. Neste contexto, no presente trabalho foram obtidos de novos candidatos a fármacos com propriedades doadoras de NO e antiagregantes plaquetárias, através da estratégia de hibridação molecular dos AINEs contendo uma subunidade doadora de óxido nítrico, representada pelos furoxanos, e espaçada por uma subunidade N-acil hidrazônica. Dessa forma, a inibição da síntese de tromboxanos associada à doação de óxido nítrico permitiu atuação nas plaquetas através de um mecanismo múltiplo de ação com fins de diminuição da agregação plaquetária. Os produtos intermediários e finais apresentaram bons rendimentos e foram caracterizados por técnicas analíticas as quais predisseram que as estruturas propostas foram obtidas. Todos os compostos se como doadores de óxido nítrico. Os compostos 1a e 3a apresentaram atividade analgésica superior a dipirona, utilizada como controle. No ensaio de agregação plaquetária ―in vitro‖... (Resumo completo, clicar acesso eletrônico abaixo)

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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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The study of ceramic materials is constantly evolving, especially in research related to advanced ceramics. Once these have many applications, this paper relates to synthesis by solid state reaction of calcium copper titanate (CCTO) ceramic material means doping with strontium. The powders were characterized using thermal analysis techniques such as TG (thermogravimetry), DTA (differencial thermal analysis), dilatometry, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The compositions have submitted weight loss at around 6% with respect to carbonates used, and was attributed a temperature of 950° C to perform the calcination according to thermogravimetric analysis. After the process of calcination and milling, the particles presented approximately spherical shapes and high percentages of substitution Ca2+ with Sr2+ was evident by the presence of necks between to particles due to the milling calcination. Analyses with Energy Dispersive Spectroscopy (EDS) showed stoichiometries in different samples very similar to the theoretical stoichiometry

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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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A anemia falciforme é uma doença genética caracterizada por uma anemia hemolítica crônica e fenômenos vaso-oclusivos, que levam a crises dolorosas e à lesão tecidual crônica e progressiva. Tem sido relatado que pacientes com anemia falciforme apresentam aumento dos níveis circulantes de citocinas, incluindo fator de necrose tumoral-α (TNF-α). O principal fármaco utilizado no tratamento dessa anemia é a hidroxiuréia (HU), fonte exógena de óxido nítrico (NO) e responsável pela inibição da agregação de plaquetas e aumento dos níveis de hemoglobina fetal (HbF). Trabalhos prévios têm demonstrado a importância da subunidade 1,2,5-oxadiazol-N-óxido como doadora de óxido nítrico. Nesse contexto, o presente trabalho tem como objetivo sintetizar um novo derivado híbrido do 1,2,5-oxadiol-N-óxido para a formação de um composto útil para o tratamento dos processos preventivos contra agregação plaquetária exacerbado em pacientes falciformes

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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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Medo e a ansiedade são emoções que têm origem nas reações de defesa que os animais exibem diante de ameaças que podem comprometer sua integridade física ou a própria sobrevivência, tais como confrontos com o predador ou com animais da mesma espécie. Em se tratando da espécie humana, estas respostas defensivas eliciadas representariam a ocorrência de transtornos de ansiedade e, a busca por sua compreensão, resultou no desenvolvimento de modelos animais de ansiedade, dentre os quais se destaca o labirinto em cruz elevado (LCE) que é baseado na aversão natural de roedores a espaços abertos. Com relação aos substratos neurais envolvidos nestas manifestações, cabe destacar a matéria cinzenta periaquedutal bem como estruturas prosencefálicas, como o córtex pré-frontal (CPFm), uma estrutura límbica que tem sido frequentemente descrita como relevante na neurobiologia da ansiedade. O óxido nítrico (NO) tem sido investigado em diferentes estruturas cerebrais de roedores nas quais foram evidenciadas respostas pró-aversivas. Sendo o CPFm uma estrutura que contém neurônios nitrérgicos, este estudo teve o objetivo de investigar o efeito da facilitação nitrérgica através da injeção intra-CPFm de um doador de NO, o NOC-9 [6-(Hidroxi-1-metil-2-nitrosohidrazino)-N-metil-1-hexanamina], sobre o comportamento de camundongos expostos ao labirinto em cruz elevado (LCE). Métodos e Resultados: Camundongos Suíços machos (25-35g, n = 53) receberam implante de cânula guia no CPFm. Cinco dias após, os animais receberam microinjeção de veículo ou NOC-9 nas doses de (1,875 nmol; 18,75 nmol; 37,5 nmol ou 75nmol) e, após cinco minutos, foram expostos... (Resumo completo, clicar acesso eletrônico abaixo)

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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