166 resultados para aquecimento solar


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

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

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Introduction: the voice is one of the main features of interaction between teacher and student. As teachers, future teachers are also risk population for the development of dysphonia and may be subject to protective intervention. Purpose: to evaluate the effect of a vocal warm-up and cool-down procedure at Pedagogy students. Method: A quasi-experimental study, pre-posttest without a control group, with fourteen Pedagogy students at a public university, participants of a short course. The analysis was performed by a self-assessment visual analogue scale of 10 cm, considering aspects related to the body and voice. The protocol was implemented in three steps: pre-test, post warm-up and post cool-down, and it was calculated the averages of the variables of discomfort and compared the measurements before and after performing each procedure. It was used the the Wilcoxon signed-rank statiscal test, adopting a significance level of 5%. Results: there was less discomfort with statistical significance after the vocal warm-up (p=0.002) and cool-down (p=0.001), with greater magnitude in both aspects related to voice. Conclusions: The vocal warm-up and cool-down have positive effects on the perception of students and should be taught to future teachers in order to prevent vocal disorders. The vocal cool-down, poorly researched, should not be passed over vocal health practices since its purpose showed obvious improvement in the investigated group.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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

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O protetor solar é um produto extremamente importante para proteger a pele da radiação ultravioleta proveniente do sol e capaz de reduzir a incidência de câncer de pele. Os filtros solares são divididos em orgânicos e inorgânicos e, dentre os inorgânicos, se encontra o TiO2 que atua refletindo, espalhando e absorvendo as radiações UV, além de ser fotoestável e de baixo potencial de irritabilidade dérmica. Neste trabalho foram desenvolvidas formulações cosméticas em forma de gel contendo nanopartículas de dióxido de titânio capazes de agir como fotoprotetores físicos e que mantem a transparência ao serem aplicados sobre uma superfície, como a pele. Foram desenvolvidos xerogéis a base de nanopartículas de TiO2 com tamanho e superfície controlados. A partir dessas nanopartículas foi possível preparar formulações cosméticas contendo nanopartículas redispersas de xerogéis a base de TiO2. Esses sistemas foram avaliados por testes de citotoxicidade e foi obtido um resultado favorável para a continuidade da pesquisa, sugerindo o uso deste material em humanos sem causar danos. Foram feitas as caracterizações físico químicas e estruturais. A análise de FPS indicou amplo espectro da formulação, o potencial zeta mostrou que é possível evitar aglomerações das nanopartículas em pHs utilizados para formulações tópicas, a reologia demonstrou que as formulações apresentam comportamento de recuperação da consistência e organização do material inicial após seu desarranjo durante o cisalhamento. As caracterizações serviram para obter um conhecimento da estrutura química e física das amostras que contém as nanopartículas de dióxido de titânio, para que seja possível fazer uma análise crítica e melhor qualificar o protetor solar desenvolvido.

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The energy is considered one of the most important elements in the human´s life providing the survival as well as the well being. Nowadays, the technologies destined to generate power burn fossil fuels which pour gases (carbon dioxide among them) that contribute to the global warming phenomenon. Several research groups and universities have been studying different methods for generating power with low carbon dioxide emissions, including the possibility of burning zero-carbon fuels. In this text, it has been put attention to the Advanced Zero Emission Power Plants (AZEP) which separate the CO2 (from the gases involved in the power generation), compress it, dehydrate it and store it in appropriate reservoirs. The goal of this study was to find a possible solution to produce CO from CO2, activated by solar energy; the reaction between CO and steam generates a syngas comprised of H2 and CO2, which can be separated by chemical and/or physical processes. The text also contains a study concerning the compressed air energy storage power plant (CAES) and come up with its modification to C[CO2]ES. This power plant stores CO2 directing it to a reverse combustion process to produce CO which is headed to a syngas reactor to produce CO2 and H2. Hydrogen is separated and carried to the thermal cycle to generate power with low carbon emissions

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Frente ao desafio de prover água de melhor qualidade para o uso humano a um custo acessível e de simples execução, muitos métodos tem sido desenvolvidos e estudados. Uma metodologia que tem se destacado atualmente, é o método SODIS, sigla em inglês que significa, desinfecção da água por meio da luz solar. Essa metodologia tem como princípio a inativação de uma variada gama de microrganismos patogênicos a partir da ação dos raios solares. Essa metodologia consiste em submeter garrafas de água a um banho de luz solar por algumas horas. Para a realização do método SODIS pode-se utilizar garrafas PET (politereftalato de etileno), sendo que sua execução é simples e rápida além de possuir mínimos riscos envolvidos. A fim de comprovar a eficácia desse método, muitos estudos tem investigado os mecanismos e fatores importantes envolvidos no processo de inativação. Da compreensão desses mecanismos e fatores críticos, preconizou-se ações que visam garantir e maximizar a eficiência do método em variadas situações e condições climáticas sem que o método se torne complexo ou oneroso. O método SODIS se mostrou eficaz na inativação de várias espécies de fungos, vírus, bactérias e até protozoários. Estudos de campo revelaram a sua eficácia prática, ocasionando uma diminuição expressiva nas ocorrências referentes a quadros de diarréia e diarréia severa nas populações estudadas

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The aims of this work are to analyze the direct solar radiation pressure torque (TPRS) in the rotational motion of spin-stabilized artificial satellites, to numerically implement these solutions and to compare the results with real data of the Brazilian Satellite Data Collection – SCD1 and SCD2, supplied by INPE. The mathematical model for this torque is determined for a cylindrical satellite, and the components of this torque are determined in a fixed system in the satellite. An analytical solution for the spin motion equations is proposed, in which TPRSD does not affect the spin velocity of the satellite. Two approaches are adopted in the numerical implementation of the developed theory: the first one considers the proposed theory and the second introduces a variation in the spin velocity based on its real variation. The results obtained indicate that the solar radiation pressure torque has little influence in the right ascension and declination axis of rotation due to the small dimension of the satellite and altitude in which it is found. To better validate the application of the presented theory, the angular deviation of the spin axis and solar aspect angle were also analyzed. The comparison of the results of the approaches conducted with real data show good precision in the theory, which can be applied in the prediction of the rotational motion of the spin-stabilized artificial satellites, when others external torques are considered besides the direct solar radiation pressure torque

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The present work intends to study some fluid dynamic and heat transfer aspects of a solar chimney, aiming at a preliminary design of a facility. Some definitions and concepts of this system are presented. The simulation was performed based on a theoretical model validated with measurements of a prototype in Manzanares, Spain. Using the same theoretical model and some considerations, dimensions on a small scale are applied, making the model more interesting from its constructive aspect. The results show the behavior of the air velocity inside the chimney and illustrate some values of two preselected turbines. This technology looks promising in Brazilian territory due to high levels of solar radiation

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The wide territorial extension of Brazil derails the installation and maintenance of instruments for measuring solar radiation, which makes necessary the development and application of models that are able to estimate reliable and sufficient data for many different activities that use such data. And these, in most cases, are estimated from the Ångström equation. Based on this model, this project aimed to estimate the global solar radiation at Presidente Prudente-SP, Brazil, using daily data from 1999 to 2007. The solar radiation data have been extracted from the paper tapes of actinograph bi-metallic (Robitsch) daily records at the meteorological station in the Faculty of Science and Technology, UNESP. These tapes were scanned, resulting in digital images with x and y coordinates pairs (x = time; y = solar radiation, cal/min.cm²). The daily global solar radiation is the area under the curve of the image. This value has been calculated by computer algorithms. After the acquisition and calculation of the values needed to develop the Ångström equation have been determined the constants a and b, using linear regression between the values of Rg/R0 (solar radiation/solar radiation on a horizontal surface at the top of atmosphere), as ordered, and n/N (number of hours of sunshine/day length in hours) as abscissa. The slope of the line will be the constant b and the linear coefficient, the constant a. The estimated results were compared to the observed using the Kolmogorov-Smirnov test, realizing that the models can be accepted. So, the equation to aim the solar global radiation is: Rg = R0 (0,2662+0,3592 n/N)

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Nowadays, the biggest part of the world's energy supply comes from fossil fuels and nuclear. However, the current need of the society for the preservation of the environment and wise use of natural resources, has favored the search for alternative energy sources and improvement of energy efficiency. In this new scenario, companies are beginning to mobilize in order to adapt its facilities to renewable energy. Solar, with its immense potential, not really exploited yet, can be very useful for companies that want to beat their sustainability goals. Given these facts, the aim is to evaluate the economic viability of introducing a solar water heater which uses a colorless PET bottle as one of its components in a plant. The hot water generated will heat the air of a paint booth and a warm house, reducing energy consumption, since they are heated by electric heaters

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Hypothermia is a common phenomenon in the perioperative period, and it affects 60 to 90% of patients submitted to anesthetic-surgical procedures. In order to minimize its incidence, warming methods are used. Such methods can be passive, such as orthopedic cotton, sheets and blankets, or active, such as warm-air blankets and thermal mattresses. In this scenario, the present study aimed at comparing two warming methods used in the intraoperative period. Patients submitted to abdominal surgery in the specialties of gynecology and gastric surgery from August to September 2010 were included in the study. After randomization, they were divided into two groups: one using a thermal blanket (group I) and one using orthopedic cotton (group II). At last, 9 patients were included. The variables for each question were considered according to occurrence frequency. Comparison between groups was performed by Student’s t test. With the purpose to analyze whether there was an association, the chi-square test or Fisher’s Exact test was used. Whenever it was applicable for multiple comparisons, Tukey’s test was utilized; p values < 0.05 were considered to be statistically significant for analysis. The sample comprised 6 males and 3 females submitted to gynecological and gastric surgeries. Their mean age was 48 years for group I and 46.2 years for group II. A predominance of general anesthesia was observed. The time of permanence in the operating room ranged from 80 to 360 minutes. With regard to warming parenteral solutions, the procedure was performed on 5 patients, and infusion of warm solution into the abdominal cavity was performed on 50% of the sample. Concerning the warming method used, 5 patients used a thermal blanket. In view of the results presented, it was not possible to conclude which warming method should be used due to sample size