Localização de descargas parciais em transformadores de potência por meio de sensores piezelétricos de baixo custo e sistemas inteligentes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudos CTS e transgenia: análise de materiais didáticos do ensino médio

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Membranas de biocelulose como substrato para o crescimento de nanofios de ZnO: síntese e aplicação

Pós-graduação em Química - IQ

Nanopartículas de Pd suportadas em compósitos óxido-carbono: influência das interações metal-suporte na oxidação de etanol em meio básico

Fuel cells powered directly with ethanol (Direct Ethanol Fuel Cell-DEFC) are very attractive for the possibility of using a renewable fuel in the generation of clean energy. However, it is still necessary to deepen the understanding of catalytic processes and their dependence on the catalytic properties. This work proposes to study the catalytic activity of ethanol oxidation in an alkaline medium of Pd nanoparticles supported in carbon oxide hybrids using various transition metal oxides (MoO3, TiO2, WO3 and ZrO2). The materials prepared were characterized by techniques such as X-ray diffraction, transmission electron microscopy (TEM) and X-ray dispersive spectroscopy (EDX) to verify the structure, the distribution of particles in the supports and the presence of Pd on particles oxide. Experiments of X-rays absorption spectroscopy were carried out using soft X-rays (SXS) to evaluate the changes in the electronic properties of the Pd particles caused by interactions with different oxides. Measurements of cyclic voltammetry and potential sweeps of adsorbed CO oxidation allowed evaluating general aspects of the catalysts' electrochemical behavior and determining the electrochemically active area thereof. The catalytic performances of ethanol oxidation in alkaline medium were evaluated by electrochemical techniques (potential scan and chronoamperometry), and showed an improvement in activity with the addition of oxides in material containing only carbon, which was most pronounced for the catalyst containing TiO2. This improvement was predominantly associated with the electronic effects caused by the interaction of Pd on the support, causing a vacancy in the 4d band of Pd which, in turn, produces variations in adsorption energies of the species...

Educação ambiental e o uso de materiais audiovisuais em teses e dissertações brasileiras em educação ambiental

Levando em conta o modelo de desenvolvimento vigente, consideramos o momento atual, de crise ambiental, como fruto do estabelecimento de uma postura antropocêntrica frente à natureza. Assim, a EA vem sendo apontada como uma das possibilidades de mudança deste cenário. A EA que propomos se apoia em três dimensões, estabelecidas por Carvalho (1989), com especial enfoque na dimensão valorativa. Dentre os recursos potencialmente relevantes para o desenvolvimento da EA, destacamos o cinema ficcional e documentário. Possuidor de uma linguagem própria, o cinema pode e deve ser utilizado, visto que sua presença na sociedade atual é intensa. Dentre as inúmeras qualidades que este recurso possui, consideramos que ele apresenta imenso poder de atrair a atenção dos alunos, uma vez que possui por si só técnicas únicas para tal finalidade. O uso do cinema em sala de aula, entretanto, exige alguns cuidados e preparativos por parte de quem se propõe a utilizá-lo com este fim, ou corre-se o risco de recair em um uso corriqueiro, a fins de entretenimento, e portanto sem qualquer finalidade educativa. As perguntas que permeiam o presente trabalho são: este assunto tem sido abordado em teses e dissertações voltadas a pesquisas envolvendo a EA? Se sim, quais fundamentações teóricas abarcam, e o que está sendo levando em consideração para sua execução? Que aspectos significativos têm sido apontados sobre esses recursos, que podem subsidiar os trabalhos de EA? Para a coleta das teses de interesse, recorreremos ao banco de dissertações e teses de educação ambiental desenvolvido pelo projeto de pesquisa interinstitucional denominado Educação ambiental no Brasil: análise da produção acadêmica (teses e dissertações) - EArte. Verificamos que, apesar de muitos trabalhos apontarem o uso de filmes em suas pesquisas, este uso ainda é feito de maneira superficial e é tido apenas como mais um recurso de apoio. Existe uma...

Profissionalização da estrutura administrativa de empresas familiares: comércio varejista de materiais de construção

One of the existing business models is the family business. This paper deals with the structure of family businesses. With the purpose to analyzing the input and output processes of goods, and management behavior in decision-making, looking for the professionalization of the family business administration. This paper is a case study in a construction materials shop, with an applied research due to their nature, according to his purpose takes the characteristic of exploratory research, using interviews, observation and analysis of company data. During the analysis of processes in the company were noted some shortcomings. Given this fact, made the comparison with the theories found, proposals were generated improvements to be accomplished within the company structure

A participação dos medidores eletrônicos na rede inteligente de energia elétrica

Depuis que l'électricité a été découverte et que le secteur électrique s'est considérablement développé dans le XVIIIe siècle, jamais l'homme n'a pu se détacher de cette énergie. Pendant longtemps le système d'énergie électrique a fonctionné sans grand changement, mais avec le développement rapide des technologies, de nouvelles améliorations apparaissent. Ce mémoire traite des nouveaux concepts de réseaux d'énergie électrique appelés Réseaux intelligents ou Smart Grid. À travers un panorama de leurs développements dans le monde, cette étude porte d'une part, sur l'avancée des projets dans quelques pays et d'autre part, du niveau de développement de ce réseau au Brésil et de son intérêt pour le pays. L'étude a comme point central un des composants de ce réseau intelligent, le compteur communicant, qui est l'élément essentiel des interconnexions entre consommateurs et producteurs. Ce rapport apporte un éclaircissement sur les compteurs conventionnels et les compteurs intelligents et sur leur mode de fonctionnement. Enfin il aborde la question des consommateurs : par quels moyens leur transmettre tous ces changements à venir, puisque jusqu'à présent, leur seule participation était de payer l'énergie consommée. Avec le nouveau réseau, ils deviendront de véritables acteurs puisqu'ils seront informés en temps réel de leur consommation d'énergie électrique. Pour terminer, le mémoire montrera comment ils pourront s'adapter à cette nouvelle façon de gérer leur consommation en ésperant les inciter à une utilisation plus raisonnable de l'énergie et à modifier leur comportement en gérant de manière active leur consommation en intégrant notamment les énergies renouvelables

Estudo das propriedades ópticas de pós cerâmicos à base de Zn3Ga2Ge2O10: X% Cr3+ (X = 0 ; 0,5 ; 0,75 ; 1,0)

Ceramic powders based on Zn3Ga2Ge2O10: Cr3+ X% (X = 0.0; 0.5; 0.75; 1.0) were synthesized by solid-state reaction method. The gallium-zinc germanate doped with chromium presents an interesting property of phosphorescence, that means, it is capable of emitting light when excited by a source of radiation, and such emission remains for some time after stopping the source. For this reason, these materials can be widely applied in night-vision surveillance, (through the use of solar energy, for example), electronic devices screen, emergency routes signals, control panels indicators in dark environments, etc. In this job were considered different amounts of dopant in order to perform a comparison of structural and photoluminescent properties. For that, some analyses were performed on samples, such as XRD, FT-Raman, SEM, UV-vis and photoluminescence measurements (PL). Such analysis allowed to infer that the presence of chromium results in no phase transformation, so that the four compositions have the same set of phases: cubic, rhombohedral and hexagonal. Although the structure was not changed, chromium influences other properties / characteristics of these materials. Examples are: increase of band-gap, decrease of average particle size, small changes in binding energy checked by Raman and especially the increase of photoluminescent property. The chromium ions have great ease in replacing gallium ions in octahedral sites, resulting in emission of light with a wavelength of about 700 nm (infrared region), which is justified by the spin-forbidden 2E 4A2 transition. In other words, chromium is a favorable luminescent center, acting as a trap in the crystal structure, since it imprisons the excitation energy easily and releases it gradually, allowing the phosphorescence. It was observed that the composition ... (Complete abastract click electronic access below)

Estudo da viabilidade de produção da peça alimentação/ladrão para banheiras

The product development field daily works in the chase of new materials and technologies that fulfills the requirements of the consumer market. So, projects are developed in order to theoretically predict what will actually happen. The production of household appliance is not different. To provide a pleasant bath to the costumer, the manufacture of a bathtub counts on many components. With this in mind, this work goal is to study the possibility of production by plastic injection of the assembly water source/overflow pipe used in bathtubs and compare its production cost with the cost of the assembly acquired from third parties. The injection process is widely used on the world stage because of its numerous advantages, however, due to the high cost of the molds, it is important to estimate the time required for the return of the initial investment. To do this, a model was designed to examine its dimensions and then initiate the study of the possibility to inject the components with the available injection machine and the production cycle. With the results, it was found that there was a reduction in the cost of the finished assembly, but a very long time to return the initial investment due to the current financial scenery of the country

O professor de biologia e a possibilidade de uso de diferentes abordagens de ensino com materiais midiáticos a fim de desenvolver a criticidade do aluno do ensino médio

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento e estudo de materiais híbridos siloxano-poli(óxipropileno) para liberação prolongada do cloridrato de propranolol

Pós-graduação em Química - IQ