464 resultados para Faixa de temperatura
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Distribution networks are formed by long lines that carry electricity substations to homes and industries. These lines have associated impedance and depending on operating conditions of the network these impedances may vary. This paper provides a detailed analysis of the effects observed in studies of voltage drop, short circuit and electrical losses, when considered the drivers sequence impedances used in primary distribution network at different temperatures. Therefore, it is initially presented a calculation methodology and details the factors that influence the final values. The methodology presented tackles in a practical way the main factors that directly or indirectly influence the values of the impedances as an emblematic example and will be properly dealt with throughout the paper is the effect of temperature on the values of the sequence impedances. More specifically is dealt with the case of XLPE cables protected, by having a higher maximum operating temperature than the operating temperature of the network. The effects observed in the power flow generated when considering the impedance values at both temperatures were analyzed. The impedance drivers tend to increase with increasing temperature. Thus the impedance of the conductor XLPE protected will tend to be greater for the maximum operating temperature for which the operating temperature of the network, resulting in greater voltage drop and higher electrical losses
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Because the high consumption of welded pipe for exploration and conduction oil and gas, optimization of manufacturing processes is necessary to obtain better productivity, efficiency and cost reduction. The objective of this study is to analyze the forms of heat transfer during the welding of pipes using longitudinal submerged arc process them to propose a model for the temperature distribution in the welded region. For this analysis are addressed as the heat transfer modes operate in the specified welding process and the necessary considerations for the mathematical model were obtained. The calculations were performed and the simulations needed to obtain the temperature distribution in the tube were carried out. Therefore, the practice was satisfactory and the results showed a range of temperatures along the pipe for a particular model and the future suggestions for improvement of this work
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Pós-graduação em Zootecnia - FCAV
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Pós-graduação em Geociências e Meio Ambiente - IGCE
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Pós-graduação em Geociências e Meio Ambiente - IGCE
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Several periodontal procedures have been described in the literature to correct mucogingival alterations or to achieve root coverage. The epithelized free gingival graft is a well established periodontal surgery to increase the width of keratinized gingiva with good stability in the long term follow up. However, this procedure is not commonly used in aesthetic areas since the grafted tissue presents differences of color and contrast. The free connective tissue graft emerges as a viable option to increase attached gingiva in areas where aesthetics results are required. The removal of an epithelized free gingival graft from the hard palate region creates a sore and raw surgical wound that slowly repairs, while the connective tissue graft produces only a line of incision that can be easily sutured promoting a more confortable outcome for the patient. This paper aims to report a case where a free connective tissue graft was used to increase the width of attached gingiva in a tooth with gingival recession. This technique presented satisfactory esthetics results, with a better contrast and color matching with the surrounding tissues.
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Temperature is certainly one of the major factors that affect biochemical and physiological processes. So, the investigation of how animals regulate body temperature (Tb) and respond to changes in ambient temperature is indispensable. There are five thermal states defined up to date that include euthermy, hypo and hyperthermia (forced fall and increase of Tb, respectively), fever and anapyrexia (regulated increase and fall of Tb, respectively). In this review, we present some classic and recent data about thermoregulatory mechanisms involved in those thermal states with special attention directed to anapyrexia, a phenomenon that has attracted the interest of researchers due to its potential therapeutic benefits.
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Pós-graduação em Ciência e Tecnologia Animal - FEIS
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Pós-graduação em Microbiologia Agropecuária - FCAV
Qualidade e alterações estruturais do café arábica submetido a alternância da temperatura na secagem
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Pós-graduação em Agronomia (Energia na Agricultura) - FCA
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Pós-graduação em Ciência e Tecnologia de Materiais - FC
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Amilases e proteases constituem um dos principais grupos de enzimas industriais pelo seu amplo espectro de aplicações biotecnológicas. Elas podem ser obtidas a partir de fontes microbianas e com altos rendimentos por processos de fermentação em estado sólido (FES). Conhecer as características bioquímicas das enzimas é fundamental para adequação aos processos industriais. O objetivo do trabalho foi determinar a melhor temperatura para atividade das enzimas amilase e protease de Rhizopus oligosporus obtidas por fermentação em estado sólido utilizando farelo de trigo como substrato. Os melhores valores para atividade amilolítica e proteolítica foram obtidos nas temperaturas de 55 - 65 °C e de 50 - 60 °C, respectivamente. Estes resultados sugerem que as enzimas estudadas podem ser utilizadas em processos que empregam elevadas temperaturas.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Engenharia e Ciência de Alimentos - IBILCE