7 resultados para Películas

em Universidade Federal do Rio Grande do Norte(UFRN)


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This study proposes to do a study on the mathematical modeling of permeation of films based on chitosan. To conduct the study were obtained membranes with various compositions: a virtually pure membrane-based chitosan; one of chitosan associated with poly (ethylene oxide (PEO). The membranes of pure chitosan were treated with plasma in atmospheres of oxygen, argon and methane. The various types of films were characterized as to its permeation regarding sufamerazina sodium. In the process of mathematical modeling were compared the standard method of obtaining the coefficient of permeation recital straight down the slope of the plot obtained by extinction / time with a the integration process of numerical permeability rate will be calculated from the spectroscopy UV

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In general, among the corrosion inhibitors surfactants are the most commonly used compounds, because they are significantly effective by forming protective films on anodic and cathodic areas. In this study, microemulsions containing he biodegradable saponified coconut oil as surfactant (SME-OCS) was used as green corrosion inhibitors. With this purpose, methanolic extracts of Ixora coccinea Linn (IC) and a polar fraction rich in alkaloids (FA) obtained from Croton cajucara Benth solubilized in the SME-OCS system were examined in the presence of AISI 1020 carbon steel, in saline solution (NaCl 3,5 %). The efficiency of corrosion inhibition of IC and FA were evaluated in the following microemulsions: SME-OCS-IC and SME-OCS-FA. The microemulsion system SME-OCS in the presence and absence of IC and FA was assessed by measurements of weight loss and the electrochemical method of polarization resistance, with variation in the concentration of IC and FA (50 - 400 ppm), showing significant results of corrosion inhibition (83,6 % SME-OCS; 92,2 % SME-OCS-FA; and 95,3 % SME-OCS-IC)

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El presente trabajo es el resultado de una investigación llevada a cabo con un grupo de etnia romaní Calon, en el territorio de Seridó, específicamente la ciudad de Florânia, estado do Rio Grande do Norte / RN, como un lugar con la Escola Municipal de Domingas Francelina das Neves . El grupo se trasladó a las pruebas de un nuevo espacio en la ciudad en los principios de l980, la construcción de casas para vivir de esta manera y fundar una escuela para sus hijos, desde el consumo de una cultura diferente a la manera de vivir y estar en el mundo, si los usuarios que hacen de las políticas públicas establecidas grupos sociales. Hemos elegido como base para el análisis de la importancia teórica y metodológica de la Escuela de Cultura Cultura Historia, conceptos y prácticas, estrategias y tácticas (Michel de Certeau), la entrevista completa (Kaufmann) y la memoria (Le Goff). Como una estrategia en la investigación de campo, se utiliza la técnica de observación participante (Minayo). En este trabajo, encontramos el ejercicio de la educación para la vida familiar, la práctica social y cultural de los gitanos, el trabajo de la institución de educación y los elementos postulada por los teóricos que abordan los cambios en los estilos de vida de la inclusión en la escuela, las culturas silenciadas o negada. La investigación representa una labor de diálogo intercultural en una investigación como resultado de intensas búsquedas en fuentes documentales y de archivo, después de haber sido un cuerpo empírico, con material de lectura en los archivos públicos de la Cidade de Florânia, Escola Municipal de archivo Domingas Francelina das Neves entrevistas, fotografías, películas, cuadernos, documentos personales y diarios de circulación nacional. Nuestra investigación tuvo como resultado en los estudios de la cultura escolar y la escuela, el lugar de la escuela como un instrumento de inclusión social de grupos marginados y los grupos étnicos, sin poder, los estudios para la comprensión de la convivencia con los distintos temas de la diversidad, así como la comprensión y posibilidades de la formulación de declaraciones de política, teniendo como punto de partida las prácticas sociales y culturales de la rutina escolar

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An interesting development in surfactants science and technology is their application as corrosion inhibitors, since they act as protective films over anodic and cathodic surfaces. This work aims to investigate the efficiency of saponified coconut oil (SCO) as corrosion inhibitor and of microemulsified system (SCO + butanol + kerosene oil + distilled water), in saline medium, using an adapted instrumented cell, via techniques involving linear polarization resistance (LPR) and mass loss coupons (MLC). For this, curves of efficiency versus SCO concentration (ranging between 0 and 75 ppm) have been constructed. According to the obtained results, the following efficiency levels were reached with OCS: 98% at a 75 ppm concentration via the LPR method and 95% at 75 ppm via the MLC method. The microemulsified system, for a concentration of 15 ppm of SCO, obtained maximum inhibition of 97% (LPR) and 93% (MLC). These data indicate that it is possible to optimize the use of SCO in similar applications. Previous works have demonstrated that maximal efficiencies below 90% are attained, typically 65% as free molecules and 77% in microemulsified medium, via the LPR method in a different type of cell. Therefore, it can be concluded that the adapted instrumented cell (in those used methods) showed to be an important tool in this kind of study and the SCO was shown effective in the inhibition of the metal

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This study had the goal of make a dialogue between queer theory and the thoughts of the French philosopher Maurice Merleau-Ponty in the categories of body and sexuality. From this dialogue, other goals were designed, namely: identify possible recurrences of the experience of bodies and queer sexualities, designed under Merleau-Ponty’s perspective, to the knowledge of Physical Education and reflect on this domain of knowledge using the notions of queer epistemology and esthesia. The study had as methodology the phenomenological attitude proposed by Merleau-Ponty and use the reduction as technic of research. Trying linking these thoughts we used the cinema of the Spanish director Pedro Almodóvar as perceptive strategy, an exercise of look as possibility of reading the world and new ways of perceiving the human being. We appreciate three films, namely: All About My Mother (1999), The Skin I Live In (2011) and Bad Education (2004), which put us in touch with bodies and queer sexualities, with the body of esthesia, of the ecstasy, sensations and lived experiences, un type of art whose contours are not fixed or determinable, postulate by Merleau-Ponty. The philosopher, provide a rich conceptual view of the body and their sexual experience, extends and opens horizons of thought and reflection about queer experience, one experience indeterminate and contingent as a singular way of inhabiting the world. Those horizons opened by the philosopher and added to the queer perspective contribute to put in question the modes of knowledge production and the knowledge about body and sexuality in Physical Education. Finally, we point that this theoretical conversation give us clues to reflect about the reverberations of a queer epistemology for Physical Education usiging one type of knowledge guided by esthesia and sensitivity as marks of another scientific rationality.

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This study proposes to do a study on the mathematical modeling of permeation of films based on chitosan. To conduct the study were obtained membranes with various compositions: a virtually pure membrane-based chitosan; one of chitosan associated with poly (ethylene oxide (PEO). The membranes of pure chitosan were treated with plasma in atmospheres of oxygen, argon and methane. The various types of films were characterized as to its permeation regarding sufamerazina sodium. In the process of mathematical modeling were compared the standard method of obtaining the coefficient of permeation recital straight down the slope of the plot obtained by extinction / time with a the integration process of numerical permeability rate will be calculated from the spectroscopy UV

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Resumo:

In general, among the corrosion inhibitors surfactants are the most commonly used compounds, because they are significantly effective by forming protective films on anodic and cathodic areas. In this study, microemulsions containing he biodegradable saponified coconut oil as surfactant (SME-OCS) was used as green corrosion inhibitors. With this purpose, methanolic extracts of Ixora coccinea Linn (IC) and a polar fraction rich in alkaloids (FA) obtained from Croton cajucara Benth solubilized in the SME-OCS system were examined in the presence of AISI 1020 carbon steel, in saline solution (NaCl 3,5 %). The efficiency of corrosion inhibition of IC and FA were evaluated in the following microemulsions: SME-OCS-IC and SME-OCS-FA. The microemulsion system SME-OCS in the presence and absence of IC and FA was assessed by measurements of weight loss and the electrochemical method of polarization resistance, with variation in the concentration of IC and FA (50 - 400 ppm), showing significant results of corrosion inhibition (83,6 % SME-OCS; 92,2 % SME-OCS-FA; and 95,3 % SME-OCS-IC)