Análise termoquímica de reformador de etanol: produção de hidrogênio para acionamento de uma célula combustível do tipo PEM de 1 KW

Pós-graduação em Engenharia Mecânica - FEG

Síntese e caracterização da cerâmica 'Ti IND. x''('Sm IND. 0,2''Ce IND. 0,8') IND. (1-x)''O IND. (2-Б) para aplicação como anodo em células a combustível de óxido sólido

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Analise exergoeconômica aplicada a microgeração em condomínios residenciais

Pós-graduação em Engenharia Mecânica - FEG

Avaliação in vitro do efeito da cafeína na inibição do vírus da Hepatite C

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Thermodynamic and economic analysis of hydrogen production integration in the Brazilian sugar and alcohol industry

One of the biggest challenges today is to develop clean fuels, which do not emit pollutant and with viable implementation. One of the options currently under study is the hydrogen production process. In this context, this work aims to study the technical and economical aspects of the incorporation process of hydrogen producing by ethanol steam reforming in the sugar cane industry and MCFC (molten carbonate fuel cell) application on it to generate electric power. Therefore, it has been proposed a modification in the traditional process of sugar cane industry, in order to incorporate hydrogen production, besides the traditional products (sugar, ethylic, hydrated and anhydric alcohol). For this purpose, a detailed theoretical study of the ethanol production process, describing the considerations to incorporate the hydrogen production will be performed. After that, there will be a thermodynamic study for analysing the innovation of this production chain, as well as a study of economic engineering to allocate the costs of products of the new process, optimising it and considering the thermoeconomics as being as an analysis tool. This proposal aims to improve Brazil's position in the ranking of international biofuels, corroborating the nation to be a power in the hydrogen era. (C) 2013 Elsevier Ltd. All rights reserved.

Stability, characterization and functionality of proton conducting NiO-BaCe0.85-xNbxY0.15O3-delta cermet anodes for IT-SOFC application

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

Análise técnica, econômica e ecológica do uso de biogás em célula a combustível de óxido sólido (SOFC)

Pós-graduação em Engenharia Mecânica - FEG

Síntese e caracterização da cerâmica de [BaZr0,1Ce0,7Y0,1Yb0,1O3-δ] para uso como eletrólito de Células a Combustível de Cerâmicas Protônicas (PCFCs)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Direct observation of oxidative stress on the cell wall of Saccharomyces cerevisiae strains with atomic force microscopy

We imaged pores on the surface of the cell wall of three different industrial strains of Saccharomyces cerevisiae using atomic force microscopy. The pores could be enlarged using 10 mM diamide, an SH residue oxidant that attacks surface proteins. We found that two strains showed signs of oxidative damage via changes in density and diameter of the surface pores. We found that the German strain was resistant to diamide induced oxidative damage, even when the concentration of the oxidant was increased to 50 mM. The normal pore size found on the cell walls of American strains had diameters of about 200nm. Under conditions of oxidative stress the diameters changed to 400nm.This method may prove to be a useful rapid screening process (45-60 min) to determine which strains are oxidative resistant, as well as being able to screen for groups of yeast that are sensitive to oxidative stress. This rapid screening tool may have direct applications in molecular biology (transference of the genes to inside of living cells) and biotechnology (biotransformations reactions to produce chiral synthons in organic chemistry.

Direct determination of Al, As, Cu, Fe, Mn, and Ni in fuel ethanol by simultaneous GFAAS using integrated platforms pretreated with W-Rh permanent modifier together with Pd plus Mg modifier

A method is proposed for the simultaneous determination of Al, As, Cu, Fe, Mn, and Ni in fuel ethanol by electrothermal atomic absorption spectrometry (ETAAS) using W-Rh permanent modifier together with Pd(NO3)(2) + Mg(NO3)(2) conventional modifier. The integrated platform of a transversely heated graphite atomizer (THGA) was treated with tungsten, followed by rhodium, forming a deposit containing 250 mug W + 200 mug Rh. A 500-muL, volume of fuel ethanol was diluted with 500 muL, of 0.14 mol L-1 HNO3 in an autosampler cup of the spectrometer. Then, 20 muL, of the diluted ethanol was introduced into the pretreated graphite platform followed by the introduction of 5 mug Pd(NO3)(2) + 3 mug Mg(NO3)(2). The injection of this modifier was required to improve arsenic and iron recoveries in fuel ethanol. Calibrations were carried out using multi-element reference solutions prepared in diluted ethanol (1 + 1, v/v) acidified to 0. 14 mol L-1 HNO3. The pyrolysis and atomization temperatures of the heating program were 1200degreesC and 2200degreesC, respectively, which were obtained with multielement reference solutions in acidic diluted ethanol (1 + 1, v/v; 0. 14 mol L-1 HNO3). The characteristic masses for the simultaneous determination in ethanol fuel were 78 pg Al, 33 pg As, 10 pg Cu, 14 pg Fe, 7 pg Mn, and 24 pg Ni. The lifetime of the pretreated tube was about 700 firings. The detection limits (D.L.) were 1.9 mug L-1 Al, 2.9 mug L-1 As, 0.57 mug L-1.Cu, 1.3 mug L-1 Fe, 0.40 mug L-1 Mn, and 1.3 mug L-1 Ni. The relative standard deviations (n = 12) were 4%, 4%, 3%, 1.5%, 1.2%, and 2.2% for Al, As, Cu, Fe, Mn, and Ni, respectively. The recoveries of Al, As, Cu, Fe, Mn, and Ni added to the fuel ethanol samples varied from 81% to 95%, 80% to 98%, 97% to 109%, 85% to 107%, 98% to 106% and 97% to 103%, respectively. Accuracy was checked for the Al, As, Cu, Fe, Mn, and Ni determination in 10 samples purchased at a local gas station in Araraquara-SP City, Brazil. A paired t-test showed that at the 95% confidence level the results were in agreement with those obtained by single-element ETAAS.

Tracing heme in a living cell: hemoglobin degradation and heme traffic in digest cells of the cattle tick Boophilus microplus

Heme is present in all cells, acting as a cofactor in essential metabolic pathways such as respiration and photosynthesis. Moreover, both heme and its degradation products, CO, iron and biliverdin, have been ascribed important signaling roles. However, limited knowledge is available on the intracellular pathways involved in the flux of heme between different cell compartments. The cattle tick Boophilus microplus ingests 100 times its own mass in blood. The digest cells of the midgut endocytose blood components and huge amounts of heme are released during hemoglobin digestion. Most of this heme is detoxified by accumulation into a specialized organelle, the hemosome.We followed the fate of hemoglobin and albumin in primary cultures of digest cells by incubation with hemoglobin and albumin labeled with rhodamine. Uptake of hemoglobin by digest cells was inhibited by unlabeled globin, suggesting the presence of receptor-mediated endocytosis. After endocytosis, hemoglobin was observed inside large digestive vesicles. Albumin was exclusively associated with a population of small acidic vesicles, and an excess of unlabeled albumin did not inhibit its uptake. The intracellular pathway of the heme moiety of hemoglobin was specifically monitored using Palladium-mesoporphyrin IX (Pd-mP) as a fluorescent heme analog. When pulse and chase experiments were performed using digest cells incubated with Pd-mP bound to globin (Pd-mP-globin), strong yellow fluorescence was found in large digestive vesicles 4 h after the pulse. By 8 h, the emission of Pd-mP was red-shifted and more evident in the cytoplasm, and at 12 h most of the fluorescence was concentrated inside the hemosomes and had turned green. After 48 h, the Pd-mP signal was exclusively found in hemosomes. In methanol, Pd-mP showed maximal emission at 550 nm, exhibiting a red-shift to 665 nm when bound to proteins in vitro.The red emission in the cytosol and at the boundary of hemosomes suggests the presence of heme-binding proteins, probably involved in transport of heme to the hemosome. The existence of an intracellular heme shuttle from the digestive vesicle to the hemosome acting as a detoxification mechanism should be regarded as a major adaptation of ticks to a blood-feeding way of life. To our knowledge, this is the first direct observation of intracellular transport of heme in a living eukaryotic cell. A similar approach, using Pd-mP fluorescence, could be applied to study heme intracellular metabolism in other cell types.

Continuous ethanol production in a nonconventional five-stage system operating with yeast cell recycling at elevated temperatures

Three ranges of increasing temperatures (35-43, 37-45, 39-47degreesC) were sequentially applied to a five-stage system continuously operated with cell recycling so that differences of 2degreesC (between one reactor to the next) and 8degreesC (between the first reactor at the highest temperature and the fifth at the lowest temperature) were kept among the reactors for each temperature range. The entire system was fed through the first reactor. The lowest values of biomass and viability were obtained for reactor R-3 located in the middle of the system. The highest yield of biomass was obtained in the effluent when the system was operated at 35-43degreesC. This nonconventional system was set up to simulate the local fluctuations in temperature and nutrient concentrations that occur in different regions of the medium in an industrial bioreactor for fuel ethanol production mainly in tropical climates. Minimized cell death and continuous sugar utilization were observed at temperatures normally considered too high for Saccharomyces cerevisiae fermentations.

A high dynamic range method for the direct readout of a dynamic phase change in homodyne interferometers

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

Cell and humoral immunity in endemic pemphigus foliaceus

Foram avaliados dezesseis doentes portadores de pênfigo foliáceo endêmico, dez com a forma localizada da doença (Grupo G1) e seis com a forma disseminada (Grupo G2), com os objetivos de correlacionar o quadro clínico e laboratorial desses pacientes com o perfil imunológico dos mesmos, e verificar a relação dos títulos dos anticorpos antiepiderme circulantes, identificados pela imunofluorescência indireta, com intensidade da lesão e com a evolução das lesões em tratamento. Foram realizados: hemograma completo, quantificação de subpopulação de células mononucleares por anticorpos monoclonais e estudo da transformação blástica de linfócitos e quantificação de anticorpos circulantes por meio da reação de imunofluorescência indireta. Observou-se leucocitose principalmente no grupo G2, diminuição dos valores relativos das subpopulações de linfócitos CD3+ e CD4+ e tendência à diminuição dos valores relativos da subpopulação CD8+ nos doentes (Grupos G1 e G2). Os índices de transformação blástica de linfócitos frente à fitohemaglutinina revelaram níveis mais elevados nos doentes (Grupos G1 + G2), que nos controles. A reação de imunofluorescência indireta foi positiva em 100% dos doentes do grupo G2 e em 80% do grupo G1 A mediana dos valores dos títulos foi maior no grupo G2, quando comparado com o grupo G1. A análise global dos resultados permite concluir que a imunidade celular está preservada, e que existe uma relação entre os títulos de anticorpos obtidos à reação de imunofluorescência indireta e extensão da lesão cutânea.

Evaluation of castor oil-based polyurethane membranes in rat bone-marrow cell culture

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)