Avaliação da resistência ao desgaste de aluminas nanométricas produzidas a partir da decomposição térmica de acetato de alumínio liofilizado

Ensaios de resistência ao desgaste, na modalidade pino-contra-disco com pares deslizantes, foram realizados em pinos confeccionados a partir de pós de alumina proveniente do processo de decomposição térmica de acetato de alumínio liofilizado. Pós de alumina referentes às fases a-Al₂O₃ e g-A₂O₃, com e sem aditivos de sinterização (MgO e La₂O₃), foram usados para confeccionar pinos de desgaste. Pinos feitos também a partir de alumina comercial (A1000 SG) foram analisados e os resultados foram comparados. Os ensaios foram feitos de acordo com norma ASTM e mostraram que os pinos confeccionados a partir de a-Al₂O₃ têm elevada resistência ao desgaste, comprovada pelos ensaios de perda de massa e microscopia eletrônica. Os pinos de g-Al₂O₃ tiveram desempenho intermediário e os pinos de A1000 SG mostraram resultados menos expressivos.

Estudo da cinética de decomposição da fase martensítica na liga Cu-10%Al com adições de Ag

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Recuperação acelerada após reparo cirúrgico aberto eletivo do aneurisma da aorta abdominal: revisão sistemática da literatura

Pós-graduação em Anestesiologia - FMB

Decomposição da palhada de forrageiras em função da adubação nitrogenada após o consórcio com milho e produtividade da soja em sucessão

The objective of this study was to evaluate the straw decomposition of the Urochloa and Panicum after intercropped with corn and nitrogen fertilization, as well as, the agronomic performance of soybean in succession. The experiment was conducted in an Oxisol in Cerrado conditions under no-tillage eight years ago. After the corn harvest intercropped with grass and cutting of forage homogenization were applied N rates (0, 50, 100 and 200 kg ha-1 of N - urea source) in coverage. The plots consisted of Urochloa brizantha,Urochloa ruziziensis and Panicum maximum Tanzânia and Mombaça sown at the time of corn sowing and subplots composed by accumulated amounts of nitrogen applied in forage plants prior to the soybean cultivation (0, 250, 500 and 1000 kg ha-1 of N, after five cuts). The experimental design was a randomized block with four replications in a split plot. Soon after the last cut of the forage, proportionate amount of fresh mass of the species of each subplot was wrapped in nylon bags called Litter Bags, these being deposited in direct contact with the soil, to determine the time of decomposition of the dry mass during a period of 150 days. The nitrogen doses, as well as, the corn intercropped with forages (except with Mombaça) interfere similarly in the straw decomposition of forage and in the soybean yield in succession. All the consortiums of corn and nitrogen fertilization predecessors determined that, at 60 days after desiccation and cutting, still remained between 50 and 60% of the initial straw for no-tillage system.

Acúmulo de macronutrientes e decomposição da palhada de braquiárias em razão da adubação nitrogenada durante e após o consórcio com a cultura do milho

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

Gestão ambiental aplicada a prevenção, controle e recuperação de erosão linear acelerada no município de Ipeúna-SP

The erosion is a natural process of detachment, transport and deposition of soil and rock particles from one place to another. Human activities with no previous planning may accelerate this process, causing several damages to the environment and to society. In order to control the acceleration of these erosion processes caused by humans, prevention and improvement initiatives emerge. Regarding works which interfere directly in some of the natural resources, these initiatives must respect the intrinsic physical properties of the area of interest, if they aim to obtain effective results. Based on this scenario, this work proposes a few methods of accelerated linear erosion prevention, control and recovery in a specific area of the municipal district of Ipeúna (SP). For that matter, this study is based on a method of physiographic compartmentalization of the area, considering and integrating soil, relief, geology and the use and land cover properties of the study area. Plus, a flowchart with general orientations regarding management of eroded areas was produced, focused on the control and recovery of linear erosion. The result demonstrates the importance of careful erosion control, respecting the physical properties of each physiographic unit. The vegetative and mechanical conservationists methods, and the discipline of water flow, have found wide applicability in the study area.

Análise e simulação de modelos matemáticos para a estimativa da geração de gases em bioprocessos de decomposição anaeróbia de resíduos sólidos em aterros sanitários

Brazil faces a complex problem in respect to municipal solid waste, having been in recent years an increase of its generation without the country there be adequate for proper disposal thereof. In many states , the percentage of waste destined improperly , ie , in dumps , landfills, send- outs , among others , is greater than that disposed in landfills , which would be the most correct way to be made. It can be argued that this discrepancy is due to the high cost of implementation and operation of the landfill, and the same need large areas with physical characteristics that suit their operations . When there is a provision in properly constructed landfills , municipal solid waste grounded generate gases with high potential energy through biochemical reactions during the anaerobic decomposition of organic material stored . Such gases can be used for power generation within the landfill or other economic means . To estimate the gas generation will be sufficient for such economic compensation , there are mathematical models that make estimating the amount of gas produced . These models calculate the energy capacity and generation , using parameters obtained based on the characteristics of solid waste , climate of the region where they are grounded and grounding time . Such models have been raised and studied so that it was possible to perform simulations that demonstrate the behavior of biogas generation related to the external conditions of the landfill that interfere with biological reactions within. The results show differences between the values obtained , it shows that the preparation of the models found and used in the simulations were allocated amounts for different parameters that determine this difference in the estimate . Therefore, to rule, the models have difficulty understanding this because there is no clarity in the formulation of the equations , and the definition of variables and parameters would require a detailed study to...

Teorias de Spin-1: decomposição em helicidades, redução dimensional e imersão de calibre

We have studied the physical content of the following models: Maxwell, Proca, Self-Dual and Maxwell-Chern-Simons. One method we have used is the decomposition in the so called helicity variables, which can be done in the Lagrangian formalism. It leads to the correct counting of degrees of freedom without choosing a gauge condition. The method separates the propagating modes from the non-propagating ones. The Hamiltonian of the MCS and the AD is calculated. The second method used here is the analysis of the sign of the imaginary part of the residues of the two-point amplitude of the theory, showing that the models analyzed are free of ghosts. We also carry the dimensional reduction of the Maxwell-Chern-Simons and Self-Dual models from D = 2+1 to D = 1 + 1 dimensions. Next, we show that the dimensional reduction of those equivalent models also leads to equivalent models in D=1+1. Even more interesting is the fact, demonstrated here, that those reduced models can also be connected via gauge embedding. So the gauge embedding of the Self-Dual model into the Maxwell-Chern-Simons theory is preserved by the dimensional reduction

Estudo dos compostos voláteis da decomposição térmica dos anti-helmínticos Albendazol e Mebendazol

The albendazole and mebendazole drugs are benzimidazole derivatives and belong to the anthelmintic class. These drugs are particularly recommended for the treatment against worms present in the gastrointestinal tract of animals and humans, by acting directly on the worm metabolism. The need for thermally study drugs is related to all the parameters that these analyzes include: presence or absence of polymorphs, possible changes in the crystallinity of the drugs, as well as the quality control during the manufacturing process thereof. In this study the thermal behavior of anthelmintic albendazole and commercial mebendazole and its recrystallisation in organic solvents, such as acetic acid and formic acid in dimethylformamide to mebendazole, and albendazole were studied using TG-DSC techniques, TG-FTIR, FTIR and XRD. TG-DSC techniques were used so it could collect information about the thermal stability of the compounds steps for thermal decomposition process and also prove its melting temperature. For recrystallization of drugs in organic solvents, the TG-DSC curves were analyzed to compare and determine that the occurrence of polymorphs. The coupled TG-FTIR technique allowed the analysis of volatile products which were released during the thermal decomposition of the commercial mebendazole. The absorption spectroscopy in the infrared region was performed to mebendazole, and albendazole in order to show the difference in functional groups of both, comparing the spectra with commercial drugs and see if there was recrystallized changes in the absorption band where the drug was recrystallized or when heated. The diffraction technique by powder X-ray method was used for comparison of the crystal structures of commercial drugs and recrystallization in organic solvents to identify changes in crystallinity both, which might suggest the formation of polymorphs

Estimação de parâmetros de linhas de transmissão utilizando técnicas de decomposição modal: Aplicação em linhas com plano de simetria vertical

Pós-graduação em Engenharia Elétrica - FEIS

O invariante E(G, W, M): algumas propriedades e aplicações na teoria de decomposição de grupos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da matéria insaponificável do óleo de palma (Elaeis guineensis) na estabilidade oxidativa de óleo de soja sob estocagem acelerada em estufa

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

Acúmulo de nutrientes e decomposição do palhiço de cana em função de doses de vinhaça

Understanding the influence of vinasse application on trash decomposition and its effects on soil chemical attributes and sugar cane culture is essential for the good management of the production system. The objective of this study was to assess the time of decomposition and nutrient cycling of the green ratoon cane's trash, and their effects on soil fertility and technological components of crops, in terms of vinasse doses. The study was developed in the northwest region of Sao Paulo State - Brazil, under Eutrophic Ultisol, using the RB855453 variety. The experimental design was randomized blocks with split plot in time. The treatments were composed of four doses of vinasse (0, 50, 100 and 200 m(3) ha(-1)). There was a 20.9% reduction in the amount of crop residue remaining after one year review. The vinasse doses increased the ratoon cane's yield, without interfering in the raw material quality. The green cane system, in which the trash is deposited on the soil and vinasse application, changes the dynamics of the trash decomposition and modifies the soil fertility, contributing positively to the crop yield.

Acúmulo de nutrientes e tempo de decomposição da palhada de espécies forrageiras em função de épocas de semeadura

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

Estudo da cinética de decomposição de compósitos nanoestruturados de poli (sulfeto de fenileno) reforçados com nanotubos de carbono

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