180 resultados para Descarga atmosférica
Resumo:
Frying is a widely used method of preparing food, because it is a very fast and convenient process, and because it provides specific characteristics of color, flavor, odor, and texture, besides having great consumer acceptance. Therefore, the interest in the physiological effects that oils heated at high temperatures can cause to the human body arises. The aim of this work was to analyze the levels of frying used oil alteration in different kinds of foods served at the university restaurant at “Instituto de Biociências, Letras e Ciências Exatas” (IBILCE), in São José do Rio Preto-SP. In addition, it aims to make the restaurant aware of the good ways to fry and the commitment of providing good quality food to students and professionals of the Institute. With this purpose, determination of total polar compounds, conjugated dienoic acids, peroxide value, and fatty acid profile were analyzed. Two rapid tests were also used: 3M Fat Monitor and Oil Test kit. The results were compared with limits recommended for the disposal of oils and fats used in frying by the Brazilian Health Surveillance Agency (ANVISA), by other countries, and by other researches. Thus, it was concluded that the university restaurant provides the consumers with fried food of good quality, since none of the analyses showed results above recommended, although there is a need of improvement in the quality control of the oil used, in order to avoid unnecessary costs to the university restaurant.
Resumo:
In this work, plasma immersion ion implantation (PIII) treatments of carbon fibers (CFs) were performed in order to induce modifications of chemical and physical properties of the CF surface aimed to improve the performance of thermoplastic composite. The samples to be treated were immersed in nitrogen or air glow discharge plasma and pulsed at −3.0 kV for 2.0, 5.0, 10.0, and 15.0 min. After PIII processing, the specimens were characterized by atomic force microscopy (AFM), scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). After CFs treatments, the CF/Polypropylene (PP) composites were produced by hot pressing method. Surface morphology of as-received CFs exhibited some scratches aligned along the fibers due to the fiber manufacturing process. After both treatments, these features became deeper, and also, a number of small particles nonuniformly distributed on the fiber surface can be observed. These particles are product of CF surface sputtering during the PIII treatment, which removes the epoxy layer that covers as-received samples. AFM analyses of CF samples treated with nitrogen depicted a large increase of the surface roughness (Rrms value approximately six times higher than that of the untreated sample). The increase of the roughness was also observed for samples treated by air PIII. Raman spectra of all samples presented the characteristic D- and G-bands at approximately 1355 and 1582 cm−1, respectively. Analysis of the surface chemical composition provided by the XPS showed that nitrogen and oxygen were incorporated onto the surface. The polar radicals formed on the surface lead to increasing of the CF surface energy. Both the modification of surface roughness and the surface oxidation contributed for the enhancement of CF adhesion to the polymeric matrix. These features were confirmed ... (Complete abstract click electronic access below)
Resumo:
Pós-graduação em Engenharia Mecânica - FEG
Resumo:
Pós-graduação em Engenharia Mecânica - FEG
Resumo:
Pós-graduação em Agronomia (Ciência do Solo) - FCAV
Resumo:
Pós-graduação em Geociências e Meio Ambiente - IGCE
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Pós-graduação em Química - IQ
Resumo:
Pós-graduação em Engenharia Elétrica - FEIS
Resumo:
Pós-graduação em Agronomia (Proteção de Plantas) - FCA
Resumo:
Pós-graduação em Engenharia Mecânica - FEIS
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Pós-graduação em Geociências e Meio Ambiente - IGCE
Resumo:
Pós-graduação em Odontologia Restauradora - ICT
Resumo:
Pós-graduação em Agronomia (Agricultura) - FCA