680 resultados para Flames Premixed Laminar


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This paper presents numerical modeling of a turbulent natural gas flow through a non-premixed industrial burner of a slab reheating furnace. The furnace is equipped with diffusion side swirl burners capable of utilizing natural gas or coke oven gas alternatively through the same nozzles. The study is focused on one of the burners of the preheating zone. Computational Fluid Dynamics simulation has been used to predict the burner orifice turbulent flow. Flow rate and pressure at burner upstream were validated by experimental measurements. The outcomes of the numerical modeling are analyzed for the different turbulence models in terms of pressure drop, velocity profiles, and orifice discharge coefficient. The standard, RNG, and Realizable k-epsilon models and Reynolds Stress Model (RSM) have been used. The main purpose of the numerical investigation is to determine the turbulence model that more consistently reproduces the experimental results of the flow through an industrial non-premixed burner orifice. The comparisons between simulations indicate that all the models tested satisfactorily and represent the experimental conditions. However, the Realizable k-epsilon model seems to be the most appropriate turbulence model, since it provides results that are quite similar to the RSM and RNG k-epsilon models, requiring only slightly more computational power than the standard k-epsilon model. (C) 2014 Elsevier Ltd. All rights reserved.

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Ipomoea carnea is a toxic plant in Brazil and other tropical countries that often poisons livestock; its primary toxin is swainsonine. Some substances that interact with the endocrine system have been called endocrine disruptors (EDs). Considering swainsonine's mode of action, it is feasible to hypothesize that this compound could act as an ED. Bisphenol A (BPA), an estrogen-mimic, is considered a classical ED in rodents. This study aimed to evaluate the possible ED actions of I. cameo and BPA in male goats. Seventeen adult male goats were divided into three homogeneous groups: control (C, n = 5); IC (n = 6, received 5.0 g/kg body weight of freshly harvested I. cornea per day), and BPA (n = 6, received 25.0 mg/kg body weight of BPA per day). The experimental period was 120 days. During the experiment, blood samples were collected at 0, 30, 60, 90 and 120 days for biochemical and hormonal evaluations. On the same days, semen samples were collected for andrological evaluation, and scrotal circumference and testicular consistency were determined. The males were castrated on day 121, and fragments of testicle and epididymis were collected for histopathological evaluation. A decrease in serum T3 and T4 was observed in the IC group as well as an increase in the number of sperm with morphological alterations. In the BPA group, reduced serum 14 and a decreased percentage of sperm with plasma membrane integrates were observed. A histopathological examination revealed the vacuolar degeneration of Sertoli cells and areas of laminar patterns of calcium deposits in the IC group and vacuolar degeneration in the rete testis in the BPA group. These results indicate that both I. cameo and BPA are potential EDs in goats. This study emphasized the susceptibility of livestock to ED actions. We also demonstrated the action of I. cameo acting as EDs in the endocrine and reproductive systems. (C) 2014 Elsevier B.V. All rights reserved.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

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

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On the field of the projects of hydraulic systems exists a lot of worries when we talk about the calculate of hydraulic pumps. In this case some facts must be considerate: length of tubes, fluid characteristics, height gauge, temperature, pressure, characteristics of tubes, flow required and others. For that mathematic calculates must be developed with the objective to optimize hydraulic pumps and agree to find an ideal machine (that don't requires more energy than necessary or less energy than it requires; that is the more critical case, cause exists the risk that the fluid pumped do not agree to become in your destiny). The wrong calculate of this machine can super-size its, bringing an excessive energy consumption. Actually it's an important subject because we are in the age of lack of energy what turn it more expensive. So the correct sizing of a hydraulic pump is connected with the fact that you have to uses the enough energy resources avoiding waste. The calculate of ideal pump in the pumping system is studied during years and a lot of specialists in this subject develop equations and theories to calculate its. Some researches study about this subject and all of them become to the same conclusion: to find the ideal pump we have to know the characteristics of fluid (cinematic viscosity), the required flow , overall yield (overall of motor x overall of pump) the high gauge or discharge pressure and the loss of repression. The pressure drop can be calculated with different theories: using Hazen-Williams, Darcy e Weisbach or Chézy (1775 - that starts the researches to calculate the pressure drop). Although the most used theory and what is most near to reality is the Darcy's equation. So, in this job the Darcy's equation were choice to calculate the drop pressure that consider what kind of flow we are studying: laminar or turbulent. The determination of the best pump to be used in the ... ( complete abstract click eletronic access below)

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O município de Franca-SP situa-se na Província Geomorfológica das Cuestas Basálticas no nordeste paulista, a qual possui características ambientais próprias. De uma forma geral, a região de Franca enfrenta problemas ambientais como a suscetibilidade à erosão linear e laminar, aos movimentos de massa e ao assoreamento dos canais de drenagem. Estes problemas, por sua vez, induzem a situações socioeconômicas, como o incremento da pobreza, aglomeração urbana e, uma emergente demanda da sociedade por mudanças no âmbito da gestão local. Assim, devem ser efetuados estudos detalhados sobre o meio, a fim de minimizar e/ou evitar tais problemas. Desta forma, propos-se a realização do Zoneamento Geoambiental, o que implica no levantamento, análise, interpretação e correlação dos diferentes componentes ambientais, visando dar subsídio a órgãos públicos e proprietários rurais, tanto na fase de planejamento como na implantação de culturas agrícolas, pecuária, reflorestamento e uso da água superficial (lençol freático), de maneira racional e ambientalmente sustentável, garantindo assim a ocupação adequada do solo e a melhor conservação dos recursos naturais. O trabalho iniciou-se com a organização e reinterpretação dos dados pré-existentes (topográficos, geológicos, pedológicos, geomorfológicos, morfoestruturais, de coberturas de alteração intempérica e sócio-econômicos) e geração e/ou reorganização de novos dados e propostas para a minimização dos impactos sócio-ambientais (rede de drenagem, hipsométricos, morfométricos, tectônicos, geológicos, geomorfológicos, climáticos e bióticos) com a utilização de técnicas de fotointerpretação de diversos sensores remotos e de campo. Deste modo, a correlação de todas as informações geoambientais relativas ao município proporcionou a delimitação das suas zonas e subzonas geoambientais... (Resumo completo, clicar acesso eletrônico abaixo)

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In a combustion process involving fossil fuels, there is the formation of species Chemiluminescent, especially CH*, C2* and OH*, whose spontaneous emission can be used as a diagnostic tool. In the present work, mapping and determination of the rotational temperature of the species CH* produced in flames on a burner fueled by Liquefied Petroleum Gas (LPG) was carried out. This study is part of a project involving the characterization of supersonic combustion in scramjets engines, whose study has been conducted in the hypersonic shock tunnel IEAv laboratories. The technique used was the natural emission spectroscopy, which has as main advantage of being non-intrusive. The rotational temperature determination was made using the Boltzmann method, whose principle is to relate the emission intensity of the species to the temperature by means of spectroscopic constants established.The temperature values were determined from the analysis of electronic bands AX and BX of the radical CH*. In order to confirm the results of flame temperatures obtained by the natural emission technique, was also used the technique of line reversal sodium. The results of both techniques showed that the temperature of the flames investigated is about 2500K a 2700K

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O presente trabalho foi elaborado e realizado a fim de se demonstrar a importância da lavagem das mãos no cotidiano, uma vez que mãos humanas podem ser consideradas fonte de diversos agentes etiológicos de doenças que podem comprometer a saúde principalmente de pacientes debilitados. Para tanto, foram aplicados testes de sensibilidade a sabonetes utilizando-se métodos normatizados e validados pelo CLSI (Clinical and Laboratory Standartds Institute) e, por fim, foi verificado o efeito dos mesmos sobre biofilmes formados a partir de espécies e cepas fúngicas conseguidas por meio de lavagens das mãos de voluntários. As amostras utilizadas foram sabonetes em barra adquiridos do comércio, um de formulação bactericida (com adição de extrato de própolis) e outro de formulação comum. Foram realizadas lavagens com os sabonetes-amostra e água destilada, dentro de fluxo laminar, onde foi possível recolher a água usada no enxágüe. A partir do plaqueamento (em meio Sabouraud-dextrose com cloranfenicol 0,05%) das mãos voluntárias sem assepsia prévia, da água de lavagem e das mãos lavadas foram obtidas culturas fúngicas. Essas culturas foram selecionadas de acordo com a viabilidade de isolamento, e então foi feita a identificação das espécies. Através da triagem pelo método de identificação por ChromagarTM Candida, foi possível identificar que duas colônias obtidas das lavagens das mãos foram identificadas como C. krusei e C. albicans. C. albicans ainda pôde ser confirmada... (Resumo completo, clicar acesso eletrônico abaixo)

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This study aims to identify the environmental and social elements that should underpin the creation of a Municipal Natural Park in accordance with Law 9985/2000, establishing the SISTEMA NACIONAL DE UNIDADES DE CONSERVAÇÃO ( SNUC ) . The northeast sector of the city of Rio Claro - SP , envolving, among others , the neighborhood Mãe Preta, the most significant of the site is consolidated as an area of significant environmental value for the consolidation of a conservation area . The proposed establishment of this unit has been discussed since the beginning of this year by Secretaria Municipal de Planejamento, Desenvolvimento e Meio Ambiente de Rio Claro- SP (SEPLADEMA ) and meets the Municipal Director Plan that provides for the establishment of several protected areas in the City . The study area suffers severe pressure due to peripheral urbanization and characterized environmental fragility according to numerous studies by researchers at UNESP, Rio Claro - SP and research in situ. Stand out in soils susceptible to sheet erosion area, the presence of a large proportion of gully area subject to flooding and significant breeding capitation water for public supply

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Pós-graduação em Ciência dos Materiais - FEIS

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The aim of the present study was to describe the tridimensional morphological characteristics of the lingual papillae and their connective tissue cores (CTCs) in Sprague Dawley rats. Four types of papillae were reported on the dorsal surface. Filiform papillae were distributed on the tongue surface and after epithelial maceration a conic and multifilamentary shape of the CTCs was revealed. Fungiform papillae were reported on the rostral and middle regions covered by a squamous epithelium. After the removal of the epithelium, the shape of a volcano with the taste orifice at its top was noted. Foliate papillae were composed of five pairs of epithelial folds situated on the lateral-caudal margin of the tongue. After the removal of the epithelium, they were shown to be limited by thin laminar projections. The vallate papilla with an oval shape was present in the caudal region and delimited by an incomplete groove. The morphological characteristics of the lingual papillae of Sprague Dowley rats, three-dimensional SEM images, and the types of papillae on the dorsal surface were similar to those reported previously in other rodent mammals. The maceration technique revealed the details of extracellular matrix with varied shapes form of connective tissue cores.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The aim of this study was to build and validate a low cost reduced-scale wind tunnel for drift evaluation on pesticide application technology. The work was carried out at the NEMPA - Núcleo de Ensaio de Máquinas e Pneus Agroflorestais (NEMPA), FCA/UNESP, Departamento de Engenharia Rural, Botucatu/SP, Brazil. The wind tunnel main characteristics were an open circuit and a closed working section with a fan blowing air into the tunnel. Screens were fitted downstream after the fan in order to stabilize the air flow on the working section. The tunnel was built with 3.0 mm eucalyptus hardboard, with a total length of 4.8 m and a squared section of 0.56 m. The air flow was provided by a 180 W axial fan. The system was adjusted and calibrated to provide a laminar and stable flow at 2.0 m s-1. Validation studies were carried out by using a Teejet XR 8003 flat fan nozzle at 200 kPa (medium droplets) to apply a spray solutions containing water plus a food dye (Blue FDC) at 0,6% m v-1 mixed with two adjuvants: a polymer based anti drift formulation at 0,06% m v-1 and a sodium lauryl ether sulfate based surfactant at 0,2% v v-1. After a 10-second application the drift was collected on nylon strips transversally fixed along the tunnel at different distances from the nozzle and different high from the bottom part of the tunnel. Drift deposits were evaluated by spectrophotometry. The wind tunnel had low levels of turbulence and high repeatability of the data, which means that the flow was uniform and able to be used for carrying out measures to estimate drift. The validation results showed that the tunnel was effective to enable comparative drift measurements on the spray solution used in this work making possible the evaluation of drift risk potential under those spray technologies. The use of an adjuvant based on a polymer reduced the amount of drift from the nozzle compared to the surfactant.