882 resultados para FEG-SEM


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This article discusses what recent statistics and public reports reveal about the funding of GEERS (now the FEG) and its bottom line. The article examines (1) whether there has been a “blowout” in the scheme which guarantees the recovery of employee entitlements in liquidations and (2) what might be done to put the scheme on a firmer fiscal footing.

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We conducted a study of the quality of water distributed by Artesian Well in relation to water supply served by the public for purposes of human consumption of UNESP Campus Guaratinguetá. Two sections of the network were randomly chosen and monitored for 105 days: the stretch of the pipeline started off the Water Treatment Station of the Autonomous Service of Water, Sewage and waste in the Municipality of Guaratinguetá and ended in a point consumption of the Child Family Center, while the section B began at the output of an artesian well and finished in a point of consumption of the Department of Civil Engineering. It is the deterioration of water quality in parts A and B, through comparative analysis of Bicarbonates, Total Hardness, Total Iron, free residual chlorine, pH, Total Residual, Turbidity, Conductivity, Color, Fecal Coliforms and Total Coliforms. Among the observations that can be highlighted: the Total Hardness was found in highest concentration in the extract; for Total Iron significant variations were obtained for both parts, and reduction of this parameter in two points of consumption analyzed, not the expected increase concentration, because the contact of water along the pipe, the CRL showed significant depletion to section A, which can be related to impurities in the water, the presence of biofilm on the walls of pipes, or because this is the stretch of greater extent to be covered by water for pH, this indicated that the water is alkaline and slightly acidic stretch in section B; Turbidity was found for the higher concentration to the passage, and a considerable reduction of this parameter at point consumption due to deposition of particulate matter along the stretch, the conductivity also showed a higher concentration in the extract, as well as an increase in this parameter at the point of consumption. Upon leaving ... (Complete abstract click electronic access below)

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With the purpose of provide students with the practical contact with the operation of a thermoelectric plant, the steam plant Laboratory College of Engineering Guaratinguetá was restored, this work was undertaken so that the necessary equipment was specified for this steam plant had their instrumented processes, enabling greater precision of the measurements performed in the tests and also storing your information. The instrumentation of the plant is to approximate the practices carried out in the laboratory with real situations encountered in industrial steam plant, thus collaborating with the most comprehensive training of students and ensuring the safety of operations performed in the laboratory

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Solar energy can be considered the largest source of energy available on earth and has attracted in recent decades, attention and interest for its rational use. The use of energy sources in a sustainable manner is essential to the survival of future generations, due to the scarcity of natural resources and their exploitation in a disorderly way. Studies related to the applications of renewable sources becomes then relevant, given its great importance as regards the conscious use of resources provided by nature, with the least possible impact on it. The present study presents an evaluation of generation potential and feasibility of implementing a solar photovoltaic connected to the grid and connected to the roofs of some buildings of the Faculty of Engineering of Guaratinguetá - FEG, to supply the demand of electric energy consumption on campus and attempting to inject a possible surplus power generation in local power grid, increasing network capacity and reducing peak loads

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Steam generation plants have several industrial applications, being important for the national and global energetic matrix. Operational knowledge of steam plants is extremely important to forming a Mechanical Engineer. The facilities from Faculty of Engineering of Guaratingueta have a no operated steam pilot plant, named Thermal Machine Lab. Nowadays, the Energy Department from the faculty cannot explore this lab for its classes, even being essential to consolidate the theoretical concepts with tests simulating industrial applications. The goal of this project was to restore the operational condition of equipment of steam laboratory by fixing the equipment, and creating operational scripts for them. In a close future this lab could be used for classes, research and other applications

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The construction industry is a large consumer of natural resources and one of the largest generators of residues with significant impacts on the environment. Because of the large production of Construction Industry Residues (RCC), it is essential reliable and updated information about generation, composition and classification sources of these residues, especially for management, recycling and final disposal. RCC represent the most part of solid residues generated in a city. In this way, the management of these residues is an issue that is gaining increasing importance in the Brazilian scenario, since the legal and society requirements to internalize the sustainability in the construction process - since the extraction, use, wastage savings, reutilization until the appropriate discard has been increasing in the last years. The present work objective is updating the quantities produced and collected in Guaratinguetá-SP, based on data collected with the municipal administrative entities that act direct or indirectly in the RCC management, elaborate a detailed bibliographic review, with special attention to the graduate works that were realized in FEG about this theme. With this material, scenarios to a better adequacy of the administrative structure to managements RCC activities, as well as was suggested actions to achieve these scenarios

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The construction industry is a large consumer of natural resources and one of the largest generators of residues with significant impacts on the environment. Because of the large production of Construction Industry Residues (RCC), it is essential reliable and updated information about generation, composition and classification sources of these residues, especially for management, recycling and final disposal. RCC represent the most part of solid residues generated in a city. In this way, the management of these residues is an issue that is gaining increasing importance in the Brazilian scenario, since the legal and society requirements to internalize the sustainability in the construction process - since the extraction, use, wastage savings, reutilization until the appropriate discard has been increasing in the last years. The present work objective is updating the quantities produced and collected in Guaratinguetá-SP, based on data collected with the municipal administrative entities that act direct or indirectly in the RCC management, elaborate a detailed bibliographic review, with special attention to the graduate works that were realized in FEG about this theme. With this material, scenarios to a better adequacy of the administrative structure to managements RCC activities, as well as was suggested actions to achieve these scenarios

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numerical study of the free energy gap (FEG) dependence of the electron-transfer rate in polar solvents is presented. This study is based on the generalized multidimensional hybrid model, which not only includes the solvent polarization and the molecular vibration modes, but also the biphasic polar response of the solvent. The free energy gap dependence is found to be sensitive to several factors, including the solvent relaxation rate, the electronic coupling between the surfaces, the frequency of the high-frequency quantum vibrational mode, and the magnitude of the solvent reorganization energy. It is shown that in some cases solvent relaxation can play an important role even in the Marcus normal regime. The minimal hybrid model involves a large number of parameters, giving rise to a diverse non-Marcus FEG behavior which is often determined collectively by these parameters. The model gives the linear free energy gap dependence of the logarithmic rate over a substantial range of FEG, spanning from the normal to the inverted regime. However, even for favorable values of the relevant parameters, a linear free energy gap dependence of the rate could be obtained only over a range of 5000-6000 cm(-1) (compared to the experimentally observed range of 10000 cm(-1) reported by Benniston et al.). The present work suggests several extensions/generalizations of the hybrid model which might be necessary to fully understand the observed free energy gap dependence.

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Grain growth kinetics was studied for commercially pure magnesium subjected to equal channel angular extrusion (ECAE). The specimens were ECAE processed upto 4 passes at 523 K following all the three important routes, namely A, 13, and C. Texture and microstructures of the samples were studied using Electron Back Scattered Diffraction (EBSD) technique in a Field Emission Gun Scanning Electron Microscope (FEG-SEM). It was observed that the grain size significantly reduces after ECAE. ECAE process produces a slightly rotated B and C-2 fiber. Static annealing leads to normal grain growth with unimodal distribution of grains through out the temperature range. Average activation energy for grain growth in the temperature range studied is found to be less than the activation energy for lattice diffusion and grain boundary diffusion of magnesium. No significant change in texture during isochronal annealing for 1 hour i.e., the predominant deformation texture remains same.

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Genetic transformation systems have been established for Brassica nigra (cv. IC 257) by using an Agrobacterium binary vector as well as by direct DNA uptake of a plasmid vector. Both the type of vectors carried nptII gene and gus gene. For Agrobacterium mediated transformation, hypocotyl tissue explants were used, and up to 33% of the explants produced calli on selection medium. All of these expressed B-glucuronidase gene on histochemical staining. Protoplasts isolated from hypocotyl tissues of seedlings could be transformed with a plasmid vector by FEG mediated uptake of vector DNA. A number of fertile kanamycin resistant plants were obtained using both the methods, and their transformed nature was confirmed by Southern blot analysis and histochemical staining for GUS. Backcrossed and selfed progenies of these transformed plants showed the presence of npt and gus genes.

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Partículas nanoestruturadas têm sido amplamente utilizadas como carga de reforço em matrizes elastoméricas, sendo substitutos eficazes das cargas convencionais, já consagradas, como o negro de fumo, mica, sílica. Em especial, as argilas têm mostrado grande potencial ao que se refere a melhor dispersão na matriz polimérica, em função de sua elevada razão de aspecto. Dentro do vasto universo de argilominerais, as argilas aniônicas, também conhecidas hidróxido duplo lamelar (HDL), apresentam como vantagem a possibilidade de ser projetada estruturalmente para as mais diversas finalidades, ao se modificar os ânions ou os cátions, ou até mesmo combiná-los na estrutura lamelar. E dentre os métodos existentes para se preparar compósitos a base de elastômero/argila, a co-coagulação do látex, é uma forma bastante eficaz e economicamente viável, uma vez que a borracha obtida após processo de coagulação já contém a carga incorporada. Este trabalho se dedicou a avaliar o processo de co-coagulação do látex de NBR e HDL, visando a obtenção de nanocompósitos. Para tanto HDL de composição Mg/Al-CO3 foi modificado com ânions DS, DBS e ST e foram preparadas suspensões aquosas, utilizando como ferramentas de dispersão ultraturrax e ultrassom de ponteira. As variáveis de processo avaliadas foram tipo e teor de HDL, tempo de mistura látex/suspensão aquosa de HDL, quantidade de coagulante e velocidade de agitação. Por fim, os coágulos obtidos foram formulados para avaliar a influência dos HDL na cinética de vulcanização e também para determinação das propriedades mecânicas convencionais. Os resultados obtidos comprovaram que a metodologia de dispersão de hidrotalcita ao látex nitrílico de modo prévio ao processo de coagulação é uma alternativa viável para a obtenção de nanocompósitos. O uso do ultrassom de ponteira como ferramenta na dispersão aquosa de HDL contribuiu para maior estabilidade da suspensão e o ajuste nos parâmetros do sistema de coagulação, levaram a obtenção de grumos uniformes do ponto de vista macroscópico e microscópico. As micrografias dos coágulos não vulcanizados obtidas por MEV-FEG confirmaram as informações apuradas a partir dos difratogramas de raios-X que apontou a formação de um sistema parcialmente esfoliado, em função da ausência dos picos característicos da hidrotalcita, além de indicarem a coexistência de partículas em dimensões micrométrica a nanométricas em uma mesma estrutura. A composição química do HDL, com a presença de átomos de magnésio e alumínio combinados com grupos hidroxila favoreceu a redução tanto o tempo de indução como de pré-cura. As propriedades mecânicas que se mostraram mais sensíveis ao grau de dispersão da carga foram a dureza, a deformação permanente à compressão (DPC) e o módulo de tração a 300% de deformação (E300), em especial para os compósitos contendo 10% m/m de HDL natural e modificado com estearato. A resistência à chama dos nanocompósitos de NBR-HDL vulcanizados apresentou um ligeiro aumento quando comparados à NBR pura, visto que esta é uma característica própria da hidrotalcita, decorrente da sua composição química

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对于纳米复合材料来说,首要解决的问题就是光散射。光散射现象主要是粒子尺寸以及粒子与基质材料折射率的差异引起的。对于小粒子(<25nm),纳米粒子与基质材料之间的折射率差异不会造成明显的光散射现象,但对于较大粒子来说,为避免明显的光散射现象的发生,二者之间的折射必须吻合。由瑞利散射公式计算得知,当粒子直径大到100nm时,粒子与基质之间的折射率差值必须在0.02之内。因此,解决复合材料光散射问题有两种途径:尽量减小纳米粒子尺寸;选择折射率匹配良好的氟化物和聚合物分别作光学活性组分的基质和材料的基底材料。由于微乳液法合成纳米粒子条件温和、设备简单,所合成纳米粒子尺寸可控。本文首先研究了微乳液结构和性质,采用微乳液法合成氟化物纳米粒子,并研究了其稀土掺杂体系的光学性质。对于微乳液结构和性质的研究,本文绘制了十六烷基三甲基嗅化钱(CTAB)/正丁醇(n-C_4H_9OH)/正辛烷(n-C_8H_(18))/水(或NH4F溶液、或Ba(NO_3)_2溶液、或KNO_3-Mg(NO_3)_2混合溶液)四组分微乳体系的三元相图,观察了电导率随水(或豁溶液)含量变化的规律,很好地印证了微乳液体系的相行为。实验发现,在这四个四元体系的相图中,Ba(NO_3)_2溶液体系的油包水区域面积最大,纯水体系水包油微乳区面积最小,我们分析认为水包油微乳区面积的变化是由于体系中加入离子后对表面活性剂阳离子的静电作用所引起的。采用十六烷基三甲基澳化按(CTAB)/正丁醇/正辛烷/水体系合成了KMgF_3以及KMgF_3:Eu~(2+)纳米粒子。XRD分析表明所合成纳米粒子为立方KMgF_3单相;环境扫描电子显微镜(ESEM)分析得到所合成KMgF_3:Eu~(2+)纳米粒子粒径约为20nm。KMgF_3:Eu~(2+)纳米粒子光谱研究发现其发射峰位于360nm附近,其激发峰位于250nm附近,较KMgF_3:Eu~(2+)单晶的激发峰峰蓝移了约80nm。对KMgF_3:Eu~(2+)纳米粒子激发峰蓝移的机理进行了初步探讨。采用CTAB/2-丁醇/水微乳体系合成出球形BaF_2纳米粒子,XRD和ICP数据显示样品为纯BaF_2相;FTIR谱图证明体系中没有有机物质的存在。将由纳米粒子分散到水中所形成的胶体滴到铜网上,干燥后发现所合成粒子有自组装的特性摘要且粒子自组装形状因粒子尺寸以及样品制备过程而异。粒子的自组装完全是自发的,没有任何的化学试剂对粒子进行包覆,也没对粒子施加除超声分散之外的任何外力。当将一滴胶体溶液直接滴到铜网上,干燥后我们得到粒子的圆形自组装,较大粒子分布在外围形成一个圆,较小粒子分布在圆的内部形成环;我们将一滴BaF_2纳米粒子胶体溶液滴加到铜网上,待干燥后滴加第二滴,重复此操作两次,这样铜网上共滴加的胶体溶液为3滴,此时我们得到粒子的双平行线型组装;直接滴加3滴BaF_2纳米粒子胶体溶液到铜网上,干燥后得粒子的桶状自组装。采用CTAB/正丁醇/正辛烷/水体系于35℃下合成带有枝晶的BaF_2纳米立方。这些枝晶生长在纳米立方的两个相邻面之间呈片状弧形。粉末XRD分析表明,体系为BaF_2单相且结晶良好;用扫描电子显微镜(SEM)对粒子进行分析发现,所得纳米立方边长为400-450nm;FTIR分析表明,经处理后样品中没有有机物质残存;对枝晶的能谱分析(EDS)分析表明,枝晶中只有Ba和F两种元素而未发现C元素存在。这说明,立方上所生长的枝晶为纯BaF_2产物而非有机物质所形成的。试验发现,所合成粒子的尺寸和形状依赖于反应温度和反应时间。采用士一述体系,于25℃下反应,可得到横截面边长40nm,长200nm的立方柱状纳米粒子,并且未见枝晶。从不同反应时间所合成粒子的形状上我们可以估计纳米立方以及枝晶的住:长过程。采用CTAB/正丁醇/正辛烷/水体系首次合成了BaF_2:Er纳米粒子,并研究了掺杂浓度对粒子红外发光的影响,XRD分析表明所合成BaF_2:Er纳米粒子为BaF_2立方相,物相纯净,结晶良好;TEM分析表明在掺杂浓度为6mol%时,粒子尺寸为15-20nm,士曾大粒子的掺杂浓度(8,10和12mol%)下,其尺寸和形状无明显改变,但粒子团聚现象严重。粒子在氢离子激光器488nm激发下的荧光(PL)光谱显示,随粒子掺杂浓度的增大,其发光强度增强,半峰宽加宽。研究了BoF_2:Er纳米粒子尺寸对其发光强度的影响,通过调节体系中水含量以达到控制粒子尺寸的目的。在体系中水含量。分别为5,8,15的条件「分别合成出平均粒径约为8,10和20.5nm的粒子。从粒子的激光粒度分布图中我们可得到粒子的平均尺寸。从粒子的XRD图中我们可以发现,随粒子粒径的减小,粉末的衍射峰出现偏移的情况。对于不同种纳米粒子,粒子粒径越小,衍射峰偏移越严重;对于相同的粒子,衍射角度越大,衍射峰偏移的越严重。从三种粒子的红峰的半峰宽和有效半峰宽越宽,对于8nm粒径的粒子,我们得到其最大半峰宽为145nm或有效半峰宽173nm。而且随粒子粒径的减小,其发射峰出现红移的现象。采用CTAB/正丁醇/正辛烷/水体系首次合成了CeF_3以及掺杂浓度为17,25,30,42和50mol%的CeF_3:Lu纳米粒子。XRD分析表明,所合成纳米粒子为CeF_3六角相,物相纯净,结晶良好,即使在高的掺杂浓度下(50mol%)体系中一也无其他杂质相的存在。环境扫描电子显微镜(ESEM-FEG)分析表明,所合成CeF_3纳米粒子粒径为巧一20nm,Lu的掺入对粒子的形状和尺寸影响不明显,但在较高的掺杂浓度下粒子团聚现象严重。粒子的荧光光谱表明,CeF_3以及Lu:CeF_3纳米粒子在254nm的激发波长下的发射光谱从290nm到400nm的宽带发射,发射峰位于325nm,较单晶体的发射峰红移约30nm;Lu的掺入有利于提高CeF_3纳米粒子的发光强度,随Lu掺入量的增大,粒子的发光强度出现先增后减的情况,在掺杂浓度为30mol%时,我们得到CeF_3纳米粒子的最大发射,但在50mol%的掺杂浓度下的粒子的发射强度仍要比未掺杂体系的发光强度要强。325nln监测粒子的激发光谱是从200nm到350nm的宽带吸收,激发峰峰位于260nm左右。比CeF_3单晶体的280nm激发峰蓝移了20nm左右。而且粒子的激发光谱中未见长波方向上的肩峰,说明粒子中CeF_3纳米粒子结晶良好,且体系中氧含量低。采用自创建一步原位聚合的方法合成了聚合物包覆的纳米粒子,并采用本体聚合的方法合成复合材料。综上所述,本文采用微乳液法合成了不同的氟化物纳米粒子,并研究了其稀土掺杂体系的光学特性,为聚合物基复合材料的制备以及应用奠定了可靠的实验基础。