314 resultados para reator aeróbio


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Dissipadores de calor recobertos com filmes de diamante CVD foram desenvolvidos para acoplar a semicondutores, utilizando-se do Laboratório de Deposição de Filmes de Diamante CVD, na UNESP - Campus de Guaratinguetá e o Laboratório de Diamantes da Universidade São Francisco, em Itatiba, SP. Analisou-se o filme de diamante CVD sobre o silício, para emprego como dissipador de calor, porque o filme de diamante CVD pode ter o valor da condutividade térmica até cinco vezes superior ao do cobre e de dez vezes a do alumínio. Os filmes foram obtidos via deposição através de reator de filamento quente, trabalhando-se com vários filamentos retilíneos em paralelo, resultando assim em um processo que visou obter um filme mais uniforme e com grande área de deposição. Os dados para análises da composição química superficial dos filmes foram obtidos por Difração de Raios-X, Dispersão de Energia de Raios-X e para a verificação da morfologia e espessura do filme foi utilizada a Microscopia Eletrônica de Varredura. Para a verificação do comportamento da temperatura sobre o dissipador com o filme de diamante CVD foi utilizada uma câmera de imagem termográfica, marca Fluke, modelo Ti 40 FT. Foram obtidos filmes de 2 e 10 ?m sobre o silício. Estas espessuras ainda não oferecem um desempenho mecânico que o torne autosustentado. Do ponto de vista de desempenho térmico as análises mostraram que, mesmo com pequena espessura, o filme de diamante CVD apresentou bom resultado experimental. Os principais desafios de construção para esse dissipador de calor são a obtenção do filme com espessura acima de um mm e a garantia da qualidade do filme com a repetitividade do processo em cujo caso torna-se necessário definir as dimensões do dissipador antes da deposição do filme.

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

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A hipertensão arterial atinge uma média de 20% a 25% da população brasileira. Estudos apontam que a prática regular de atividade física além de combater o sedentarismo pode ser utilizada como meio não farmacológico de tratamento e prevenção da hipertensão. Objetivo: Verificar os efeitos do estado de ânimo gerado por exercícios não sistematizados e sistematizados na pressão arterial. Metodologia: Participaram do estudo 30 alunas que participam há mais de seis meses do Programa Saúde Ativa Rio Claro. Elas receberam treinamento duas semanas, para utilizarem o aparelho de pressão digital de pulso Fuzzy LOGIC. As participantes foram submetidas a 3 sessões de aulas (aeróbio, lúdico e força) em dias diferentes. As aulas do aeróbio contavam com 40 min de caminhada moderada, a aula de força constou 3 séries de 1 minuto, com intervalo entre as séries de 30 segundos para membros superiores e inferiores e a aula lúdica com brincadeiras não padronizadas. As aulas foram constituídas de alongamento (10 min), parte principal (40 min) e volta à calma (10 min). A pressão arterial sistólica (PAS) e diastólica (PAD) foram aferidas nos momentos: repouso (M1), término (M2), 30 minutos após a sessão (M3), 4 horas após (M4) e 8 horas após a sessão dos exercícios (M5). A análise estatística utilizada foi a Anova para medidas repetidas com 2 fatores (Momentos e Tipo de aula) com significância de p<0.05. Resultados: A PAS no M3 foi menor do que no M1 e M2 para todos os protocolos (p<0.05); para a PAD o M3 apresentou valores menores do que o M1 e M2 para todos os protocolos. Conclusão: O efeito hipotensor teve resultados mais significativos quando relacionado a prática dos exercícios do que aos estados de ânimo gerados pelos mesmos. A prática da atividade física foi capaz de alterar positivamente os estados de ânimo dos indivíduos... (Resumo completo, clicar acesso eletrônico abaixo)

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The energy is considered one of the most important elements in the human´s life providing the survival as well as the well being. Nowadays, the technologies destined to generate power burn fossil fuels which pour gases (carbon dioxide among them) that contribute to the global warming phenomenon. Several research groups and universities have been studying different methods for generating power with low carbon dioxide emissions, including the possibility of burning zero-carbon fuels. In this text, it has been put attention to the Advanced Zero Emission Power Plants (AZEP) which separate the CO2 (from the gases involved in the power generation), compress it, dehydrate it and store it in appropriate reservoirs. The goal of this study was to find a possible solution to produce CO from CO2, activated by solar energy; the reaction between CO and steam generates a syngas comprised of H2 and CO2, which can be separated by chemical and/or physical processes. The text also contains a study concerning the compressed air energy storage power plant (CAES) and come up with its modification to C[CO2]ES. This power plant stores CO2 directing it to a reverse combustion process to produce CO which is headed to a syngas reactor to produce CO2 and H2. Hydrogen is separated and carried to the thermal cycle to generate power with low carbon emissions

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Fluidization consists in a bed of solid particles acquire fluid behavior by using a fluid (in this case air) flowing through the solid particles. Because of this, it can be a good mix of these materials, as well as to show increased rates of heat and mass transport. The fluid flowing through the spaces between the particles gives an interstitial velocity, that if is too low does not cause movement of the particulates. The gradual increase in speed will generate small vibrations between the particles promotes its fluidization. Our study focus in the fluid state of solid bed , when the fluid velocity reaches a state where the drag forces are sufficient to support the weight of the solid particles making these solids behave like fluids . Knowledge of the minimum velocity required to fluidize that particles is of great importance since below this speed there is no fluidization, and far above it, the solids are carried out of the bed. The fluidized bed reactor is widely used in physics and engineering, particularly in gas-solid fluidization, with emphasis on thermochemical processes

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Recent research advances in understanding the cellular and molecular mechanisms that underlie the processes of hypertrophy and atrophy. This may contribute to development of effective therapeutic strategies to attenuate or block the loss of muscle tissue associated with aging and pathological conditions. In this context, myogenic factors that control the activity of satellite cells have been studied to better understand the events involved in the recovery of muscle mass. Among them, we highlight the Myogenic Regulatory Factors (MRFs), which have been described as potential mediators of muscle growth. The objectives of this study evaluated the morphofunctional adaptations and gene expression of MRFs (MyoD and myogenin) in skeletal muscle (soleus) subjected to an atrophic stimulus followed by physical training. It was used 64 male Wistar rats (80 days, 250 to 300 g), divided into 8 groups (n = 8): C: control animals a week, I: Animals immobilized a week, C3: control animals 3 days; R3: Animals immobilized and recovered for 3 days, T3: Animals immobilized and submitted to exercise for 3 days; C7: Animals controls 7 days; R7: Animals immobilized and subsequently recovered by 7 days, T7: Animals immobilized and subsequently subjected to exercise for 7 days. Initially, the animals in groups I, R3, R7, T3 and T7, were submitted to 7 days of immobilization of the hind limb. Muscle atrophy was confirmed after a direct statistical comparison of the values of cross-sectional area (CSA) of muscle fibers studied in animals in groups I and C, sacrificed immediately after the immobilization period. Then, the groups T3 and T7 were submitted a rehabilitation program with muscle aerobic exercise (swimming) for 3 and 7 days respectively. The groups C, C3 and C7 were kept without stimulus atrophic and were not subjected to exercise. At the end of the experiment, the animals were sacrified and the soleus muscle removed. The quantitative analysis of gene expression ...

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In the competitive judo, the form as a trainer organizes the process of his/her athlete's training is a very important task for a good acting and a better use of the technical procedures. There is great importance in determining the exercise intensity for the judocas training due to the interest for the high income in several competitions, and few studies returned for this research area, involving those athletes' different physiologic conditions. Therefore, it is necessary to improve protocols of physical evaluation for this modality, increasing his/her applicability. The present study aimed at to verify the validity of a protocol of specific aerobic test of the judo (technique ipon-seoi-nague), no exhausting, adapted of the method of CHASSAIN (1986), using deltas of variations of the lactacidemia and of the Scale of Perception of Effort of Borg, in athletes well. The test adapted to the judo constituted of four exercise series with two efforts similar (double) of 180 seconds with one interval of 90 seconds among them. The series of exercises were accomplished in consecutive days. The intensities of the double tests were of 85%, 95%, 105% and 115% of the minimum lactato for each participant. This work used the technique ipon-seoi-nague, obeying the reasons effort-pause individualized for each athlete, that you/they correspond to the intensities of exercises proposed by the protocol of CHASSAIN (1986). In that way, the athletes applied a blow (maximum speed) and they rested some seconds, depending on the regime effort-pause of the session. At the end of each collection collection of blood (25NL) of each participant's earlobe was accomplished, seeking to measure the concentration of sanguine lactato. The collections were accomplished at the end of the first and of the second efforts, in each one of the series. For the analysis of the Perception of the athletes' Effort, the Scale of Perception... (Complete abstract click electronic access below)

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The purpose of this work is to perform studies of mathematical modeling of the relationship of interaction occurring between microrganisms participants from wastewater treatment processes aimed at understanding, through simulations, such as inter-relationships can affect the performance of such units. The methodology was the implementation in FORTRAN computer language of mathematical models of microbial interactions. The first model addresses the interaction of bacteria-forming flakes and filamentous bacteria in activated sludge systems, which seeks to strike a balance between these bacteria to improve efficiency of the process. Another model is studied the interaction between bacteria and protozoa in activated sludge systems and analyzing the efficiency of the process, observing the changes in daily load. Microbial interactions in anaerobic reactors were dealt a third model, in which there is the mutualistic interaction between acidogenic and methanogenic bacteria. In a fourth and final model was examined the relationship between the bacteria Acinetobacter sp. and Gordonia sp., which are present in activated sludge systems, showing the competitive capacity of Acinetobacter sp. can control the growth of unwanted bacteria.

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Ethanol, the main automotive biofuel, has its production based on the fermentation of sugars found in biological materials and on the distillation of the alcoholic media formed during the fermentative process. Stillage is the main residue from ethanol production, containing a high organic loading in addition to acidic and corrosive characteristics. Considering the available technologies to treat stillage, we highlight anaerobic digestion, which allows the reduction of the impacts associated to pollutants loading of this effluent and the generation of energy from the methane gas produced in the process. Based on the high treatment efficiency usually associated to the anaerobic process, this work aimed to assess whether anaerobic systems applied to the treatment of stillage are energetically self-sufficient. First we evaluated the energy recovery capacity in an anaerobic reactor applied to the treatment of stillage resulting from corn-to-ethanol processing. The results indicated the great influence that a correct selection of electrical equipment and their respective operating periods have on the net energy balance of the anaerobic treatment. The high energy consumption of the heater would not allow the system to achieve a positive net energy balance – the maximum energy recovery would reach only 0.68% of the consumption. However, the replacement of the mixture equipment would result in energy gains ranging from 8.5 to 967.9% of the consumption. In this work we also assessed the efficiency of methane yields for a few studies and the correlation between some parameters of the anaerobic process. With respect to the methane yield, we noted that mesophilic systems tend to be more advantageous than the thermophilic ones (efficiency of 76.45 ± 22.51% vs. 69.40 ± 30.36%). Considering the study... (Complete abstract click electronic access below)

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This work investigated the operating conditions of a 'scramjet' through numerical simulation considering two-dimensional steady flow. Using a commercial software, FLUENT, cases of inviscid flow with and without fuel injection, turbulent flow without fuel injection, turbulent flow with fuel injection and without burning, and finally turbulent flow with fuel injection and burning are simulated

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The treatment of domestic and industrial effluents through Wastewater Treatment Plants (WTPs) generates a residue termed sewage sludge, rich in organic matter, high-volume, occasionally containing pathogens and heavy metals. The sludge generation can minimize the benefits brought by the treatment of sewage, because this residue does not always receive appropriate treatment before final disposal. The disposal is another problem related to sludge. Landfills generally does not have physical space and alternatives such as the use in agriculture requires an intense treatment that could be in many cases operational or economic unfeasible. The objective of this work is the theoretical research about the processes of stabilization of the sludge by anaerobic digestion and the methanogenic activity during the process. Through analysis of each step and contemplating each relevant factor in anaerobic digestion process in order to optimize them, we proposed a theoretical model of reactors capable of stabilize the sludge, reduce its volume and eliminate pathogens. The obtained configuration consists of two anaerobic reactors connected in series. The first one operates in the range mesophilic temperature (35 ° C) and has higher hydraulic retention time (25 days) working primarily in the stabilization of organic matter present in the sludge and producing biogas, whereas the second one operates in the thermophilic range (55 ° C) in order to eliminate pathogens, and to reduce the volume. The hydraulic retention time in the second reactor is lower (10 days). Both mesophilic and thermophilic processes were efficient in what was proposed, promoting the stabilization of organic matter present in the sludge and significant reduction of pathogens. As a final step with the sludge previously digested, it is indicated a final dehydration... (Complete abstract click electronic access below)

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A musculatura peitoral de anuros gera a potência necessária para a produção das vocalizações, tendo seu perfil histológico descrito para apenas uma espécie. Para esta, a musculatura peitoral apresenta 100% de fibras oxidativas rápidas. Entretanto, a taxa de vocalização apresenta enorme variação interespecífica, mesmo considerando espécies pertencentes a um mesmo gênero, como é o caso do gênero Scinax. Acreditamos que o perfil morfológico e histoquímico da musculatura peitoral, particularmente no tocante à capacidade oxidativa aeróbia, deve covariar com o desempenho aeróbio. Desta forma, o objetivo deste projeto foi realizar uma análise comparativa da morfologia e histoquímica do músculo peitoral de três diferentes espécies de pererecas do gênero Scinax. Os animais foram coletados durante o pico de atividade reprodutiva. Estes foram pesados e eutanaziados para a retirada dos músculos peitorais. Fragmentos musculares foram congelados em nitrogênio líquido e armazenados em freezer -80°C. Cortes histológicos (10μm), obtidos em criostato, foram submetidos à coloração HE (Hematoxilina-Eosina) para avaliação do padrão morfológico das fibras, e NADH-TR (Nicotinamida Adenina Dinucleotídeo-Tetrazólico Redutase), para avaliação do metabolismo oxidativo das fibras. Não houve diferenças qualitativas e quantitativas na morfologia e área das fibras entre as espécies. Provavelmente as diferenças comportamentais interespecíficas devem estar associadas a caracteres ultraestruturais da musculatura como capilarização, volume mitocondrial e tipo de miosina (MHC) presente na fibra muscular. O músculo peitoral de S. perereca e S. fuscovarius apresentou forte reação NADH-TR, o que demonstra alto metabolismo oxidativo, enquanto que Scinax hiemalis apresentou uma população de fibras com metabolismo oxidativo mais moderado; isso está de acordo com dados... (Resumo completo, clicar acesso eletrônico abaixo)

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This paper presents the study on the application of the electrolytic plasma for surface treatment of aluminum. A bibliographical study on the material of interest was preliminarily performed and later designed and built an electrolytic cell, including the excitation source. Unlike conventional electrolysis process, the plasma assisted carry on in the non-linear region of characteristic current/voltage curve. Therefore it requires for the on set of the process that the power supply operates on harder conditions than those on high current process. The plasma produced during the present investigation has temperatures in the range o 6,0.10 3 -7,0 .10 3 K, well above those found in conventional chemical process. It also shows a particular dynamic to promote changes on surface and to produce new materials. The plasma is generated by microdischarge in vapor or gas bubbles involved in physic-chemical processes in electrode regions of the electrolytic cell. The electrode material was the aluminum (7075). The Process Electrolytic Plasma Processing (EPP) is sensitive to various parameters such as operating voltage, current density, electrolyte, concentration of electrolyte, geometry of reactor, temperature of electrolytic solution and dynamic of the fluid in the cell. The experiments were carried on in order to find parameters for a stable abd steady operation. The choice for the electrolytic was silicate/alkali solution in various concentrations to operate in various voltage as well. Plasma was produced on negative (cathode) and positive (anode) electrode, in specific conditions. A stable operation on the cathode process was obtained with low concentration of the electrolytic in aqueous solution, current density around 250V effective voltage. For the evolution of plasma in anodic process it was required higher concentrations and higher... (Complete abstract click electronic access below)

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O Ácido Lático é um ácido orgânico que possui uma ampla gama de aplicações nas indústrias farmacêuticas, químicas e de alimentos. Ultimamente ele tem sido considerado promissor como bloco na construção de polímeros biodegradáveis (PLA), os quais podem ser usados na produção de plásticos biodegradáveis como embalagens de alimentos e utensílios plásticos e assim substituir os produtos derivados do petróleo. O Ácido Lático pode ser produzido tanto por síntese química como através da fermentação por micro-organismos. As bactérias que produzem ácido lático são chamadas de bactérias láticas e podem produzir D-(-)-ácido lático puro, L-(+)-ácido lático puro ou uma mistura racêmica dos dois isômeros. A produção de somente um dos isômeros puro é uma grande vantagem de se produzir Ácido Lático por fermentação, uma vez que uma mistura racêmica é produzida via síntese química, além disso, a produção a partir da fermentação é mais econômica. Assim, vários estudos estão sendo feitos com o objetivo de se baratear o processo de fermentação lática e de se aperfeiçoar este processo. Este estudo visa à avaliação da produção de L-(+)-ácido lático por Lactobacillus rhamnosus B103 em reator pela utilização de batelada alimentada, uma vez que este processo tem se mostrado o mais eficiente em diversos estudos. Existem vários tipos de alimentação: batelada alimentada por pulso, batelada alimentada por fluxo constante, batelada alimentada com controle por pH stat. Neste presente estudo foram avaliados além do processo de batelada, vários processos de batelada alimentada, como a batelada alimentada com controle por pH stat, batelada alimentada por pulso e batelada alimentada por fluxo constante. O processo de batelada alimentada por fluxo constante foi no qual se obteve a maior concentração final de ácido lático (149,8 g L-1), mas, a melhor... (Resumo completo, clicar acesso eletrônico abaixo)