93 resultados para Filmes semicondutores


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The technique of plasma nitriding by the cathode cage mainly stands out for its ability to produce uniform layers, even on parts with complex geometries. In this study, it was investigated the efficiency of this technique for obtaining duplex surface, when used, simultaneously, to nitriding treatment and thin film deposition at temperatures below 500°C. For this, were used samples of AISI 41 0 Martensitic Stainless Steel and performed plasma treatment, combining nitriding and deposition of thin films of Ti and/or TiN in a plasma atmosphere containing N2-H2. It was used a cathodic cage of titanium pure grade II, cylindrical with 70 mm diameter and 34 mm height. Samples were treated at temperature 420ºC for 2 and 12 hours in different working pressures. Optical Microscopy (OM), Scanning Electron Microscopy (SEM) with micro-analysis by Energy Dispersive Spectroscopy (EDS), X-Ray Diffraction (XRD), Atomic Force Microscopy (AFM) and analysis of Vickers Microhardness were used to investigate coating properties such as homogeneity and surface topography, chemical composition, layer thickness, crystalline phase, roughness and surface microhardness. The results showed there is a direct proportionality between the presence of H2 in plasma atmosphere and the quantity of titanium in surface chemical composition. It was also observed that the plasma treatment at lowpressure is more effective in formation of TiN thin film

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In recent decades have seen a sharp growth in the study area of nanoscience and nanotechnology and is included in this area, the study of nanocomposites with self-cleaning properties. Since titanium dioxide (TiO2) has high photocatalytic activity and also antimicrobial, self-cleaning surfaces in your application has been explored. In this study a comparison was made between two synthesis routes to obtain TiO2 nanoparticles by hydrothermal method assisted by microwave. And after analysis of XRD and SEM was considered the best material for use in nanocomposites. It was deposited nanocomposite film of poly (dimethyl siloxane) (PDMS) with 0.5, 1, 1.5 and 2% by weight of nanoparticles of titanium dioxide (TiO2) by the spraying method. The nanocomposite was diluted with hexane and the suspension was deposited onto glass substrate, followed by curing in an oven with forced air circulation. The photocatalytic activity of the nanocomposite impregnated with methylene blue was evaluated by UV- vis spectroscopy from the intensity variation of absorption main peak at 660nm with time of exposure to the UV chamber. Changes in the contact angle and microhardness were analyzed before and after UV aging test. The effect of ultraviolet radiation on the chemical structure of the PDMS matrix was evaluated by spectrophotometry Fourier transform infrared (FTIR).The results indicated that the addition of TiO2 nanoparticles in the coating PDMS gave high photocatalytic activity in the decomposition of methylene blue, an important characteristic for the development of self-cleaning coatings

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The natural raw materials acquired special importance beside the mineral raw materials with the need for using alternative sources to oil, because they can be used to produce biopolymers. Gelatin, produced from the denaturation of collagen, and starch, an abundant polysaccharide in various plants, are examples of biopolymers which have several technological applications, especially in films. The objective of this work is to produce polymeric bioblends with gelatin and corn starch using two types of gelatin: commercial bovine gelatin and gelatin produced from mechanically separated flesh of tilapia (Oreochromis niloticus). For the extraction of tilapia gelatin 3 distinct pretreatments, followed by extraction in distilled water under heating were performed. The properties of gelatin extracted were similar to bovine gelatin, and the differences can be explained by the difference in extraction processes and sources. Blends of commercial gelatin and starch were produced in an internal mixer from a Haake torque rheometer, to study the behavior of the gelatin mixture with starch, thus, the same compositions were processed by twin screw extrusion, to define the mixing parameters. Subsequently, the extrusion of blends of tilapia gelatin and corn starch was carried out in the same twin screw extruder. The physico-chemical, rheological and morphological properties of the blends with thermoplastic starch and gelatin were studied. It was found that various properties vary linearly with increasing concentration of the components. The blends produced are immiscible, and among the two gelatins, tilapia gelatin showed a better interfacial adhesion with the corn starch. Regarding the morphology, gelatins formed the dispersed phase in all compositions studied, even in compositions rich in starch. Can be concluded that the procedure for tilapia gelatin extraction is feasible and advantageous, and the increasing in its scale to a reactor of 30 liters is possible, with a satisfactory yield. The bioblends of bovine gelatin/corn starch and tilapia gelatin/corn starch were successfully produced, and the processing conditions were appropriate

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The thermoelectric energy conversion can be performed directly on generators without moving parts, using the principle of SEEBECK effect, obtained in junctions of drivers' thermocouples and most recently in semiconductor junctions type p-n which have increased efficiency of conversion. When termogenerators are exposed to the temperature difference (thermal gradient) eletromotriz a force is generated inducing the appearance of an electric current in the circuit. Thus, it is possible to convert the heat of combustion of a gas through a burner in power, being a thermoelectric generator. The development of infrared burners, using porous ceramic plate, is possible to improve the efficiency of heating, and reduce harmful emissions such as CO, CO2, NOx, etc.. In recent years the meliorate of thermoelectric modules semiconductor (TEG's) has stimulated the development of devices generating and recovery of thermal irreversibility of thermal machines and processes, improving energy efficiency and exergy these systems, especially processes that enable the cogeneration of energy. This work is based on the construction and evaluation of a prototype in a pilot scale, for energy generation to specific applications. The unit uses a fuel gas (LPG) as a primary energy source. The prototype consists of a porous plate burner infrared, an adapter to the module generator, a set of semiconductor modules purchased from Hi-Z Inc. and a heat exchanger to be used as cold source. The prototype was mounted on a test bench, using a system of acquisition of temperature, a system of application of load and instrumentation to assess its functioning and performance. The prototype had an efficiency of chemical conversion of 0.31% for electrical and heat recovery for cogeneration of about 33.2%, resulting in an overall efficiency of 33.51%. The efficiency of energy exergy next shows that the use of primary energy to useful fuel was satisfactory, although the proposed mechanism has also has a low performance due to underuse of the area heated by the small number of modules, as well as a thermal gradient below the ideal informed by the manufacturer, and other factors. The test methodology adopted proved to be suitable for evaluating the prototype

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In this study, it has been investigated the influence of silver film deposition onto 100% polyester woven and non-woven, on the survival of Escherichia coli and Staphylococcus aureus in contact with these surfaces. The treatment was performedin a chamber containing the working gas at low pressure (~ 10-2 mbar). Some process parameters such as as voltage: 470 V; pressure: 10-2 mbar; current : 0.40 A and gas flow: 6 and 10 cm3/min were kept constant. For the treatments with purêargon plasma using a flow of 6 and 10 cm3/min, different treatment times were evaluated, such as, 10 , 20, 30, 40, 50 and 60 minutes. Contact angle (sessile drop), measurements were used to determine the surface tension of the treated fabrics and its influence on the bacteria grow as weel as the possibilities of a biofilm formation. The formation of a silver film, as well as the amount of this element was verified byEDX technique. The topography was observed through scanning electron microscopy (SEM) to determine the size of silver grains formed on the surfaces of the fabric and assess homogeneity of treatment. The X-ray diffraction (XRD) was used to analyze the structure of silver film deposition. The woven fabric treatments enabled the formation of silver particulate films with particle size larger than the non-woven fabrics. With respect to bacterial growth, all fabrics were shown to be bactericidal for Staphylococcus aureus (S. aureus), while for the Escherichia coli (E. coli), the best results were found for the non-woven fabric (TNT) treated with a flow of 10 cm3/min to both bacteria

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Actually in the oil industry biotechnological approaches represent a challenge. In that, attention to metal structures affected by electrochemical corrosive processes, as well as by the interference of microorganisms (biocorrosion) which affect the kinetics of the environment / metal interface. Regarding to economical and environmental impacts reduction let to the use of natural products as an alternative to toxic synthetic inhibitors. This study aims the employment of green chemistry by evaluating the stem bark extracts (EHC, hydroalcoholic extract) and leaves (ECF, chloroform extract) of plant species Croton cajucara Benth as a corrosion inhibitor. In addition the effectiveness of corrosion inhibition of bioactive trans-clerodane dehydrocrotonin (DCTN) isolated from the stem bark of this Croton was also evaluated. For this purpose, carbon steel AISI 1020 was immersed in saline media (3,5 % NaCl) in the presence and absence of a microorganism recovered from a pipeline oil sample. Corrosion inhibition efficiency and its mechanisms were investigated by linear sweep voltammetry and electrochemical impedance. Culture-dependent and molecular biology techniques were used to characterize and identify bacterial species present in oil samples. The tested natural products EHC, ECF and DCTN (DMSO as solvent) in abiotic environment presented respectively, corrosion inhibition efficiencies of 57.6% (500 ppm), 86.1% (500 ppm) and 54.5% (62.5 ppm). Adsorption phenomena showed that EHC best fit Frumkin isotherm and ECF to Temkin isotherm. EHC extract (250 ppm) dissolved in a polar microemulsion system (MES-EHC) showed significant maximum inhibition efficiency (93.8%) fitting Langmuir isotherm. In the presence of the isolated Pseudomonas sp, EHC and ECF were able to form eco-compatible organic films with anti-corrosive properties

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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It s in the city spaces, molded from the uses and daily appropriations, that life is woven, as a product of the social relationships from the accumulation of history along with the present day fabric. Within this relationship, the old and the new are elements which make up this tapestry, as a result of the contribution of successive generations. The public square is seen as an example of this relationship, since it consists of a fertile space for opportunities of urban life coexistence. It is within the trace of these considerations that the present study emerges regarding the appropriation and sociability of the Tomé de Sousa Square, located in the city of Salvador, BA, having as its main focus the special relation between the cinema and the public square, as it relates to the space of the exhibition of cinematographic art. The showing of films in public squares makes possible a distinctive means of appropriation which has occurred ever since the beginning of the cinema. Today in Brazil, projects of this nature abound, which aim at presenting the seventh art to a great portion of the population which doesn t have access to conventional movie theater projection rooms. This particular Projeto Cinema na Praça Cinema in the Square Project carried out in Salvador, has become the empirical reference point for such work. This journey reveals the fascination that this great art has woven through time, attracting and charming multitudes. The cinema touches people in a special way, stirring up affectionate feelings, which are reflected in multiple social practices. Regarding this work, what stands out above all are the projections in the squares, initiatives which make it possible for the films to be watched collectively. What was taken into account in order to carry out this work were the reports of those who came regularly to watch the cinema in the Square sessions, those involved with the cinema projects team, and the film makers. To do the work, besides a bibliographical revision, observations were made of participants in the Tomé de Sousa Square, taken from semi-structured interviews with people involved with the film projection projects and those who came regularly to the cinema in the Square sessions. Also investigations were made in newspapers, printed magazines and the internet, from document and iconographic sources. The photographic documentation proved to be an important contribution to the field work. The research therefore develops from the understanding that the social practices are what make possible the uses of and the appropriation of the spaces. Within this perspective the public square emerges as a privileged locus where possibilities flourish for multiple manifestations that social practices can generate

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Soulignant l´importance des transformations du discours politique du cinéma brésilien actuel, cet étude entreprend une analyse de la dimension éthique du cinéma de Walter Salles. Pour cela, nous avons parti de trois films long-métrages du directeur: Terra Estrangeira, Central do Brasil et Abril Despedaçado. Les films sélectionnés constituent les trois diférents chapitres de cette mémoire de maîtrise, qui s´articulent a des diférentes dimensions de l´éthique - l´hospitalité, la réliaison, et le pardon- et se présentent em format essayistique. Au texte, ces dimensions éthiques émergent à partir des récits, surtout des expériences existencielles des protagonistes et de ses singulières rencontres avec l´altérité. Comme tel, dialoguent avec des réflétions d´auteurs comme Edgar Morin, Zigmunt Bauman, Julia Kristeva, Paul Ricoeur et Hannah Arendt. Des diférents régistres de la connaissance -artistique, scientifique, religieuse- s´articulent donc dans le travail, et dialoguent en condition d´égalité. La recherche fait usage de matériels multiples qui incluent, au-delà des films mentionnés, et de ses respectifs scripts, des références à d´autres long-métrages et documentaires du directeur, ainsi que, des makingoffs, entretiens, et interprétations de commentaristes comme Lucia Nagib, Luiz Zanin Oricchio, Ivana Bentes, Pedro Butcher e Jurandir Freire Costa

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The present work is an exercise of analysis of cultural practices related to movie consume by the clients of video rental stores in Natal city (Rio Grande do Norte, Brazil). With sociology of practice as support, especially that one which develops from the seminal works of Anthony Giddens and Pierre Bourdieu, we have searched, from the apprehension of the narratives build up by these actors from the movies they attend, to point the way they build exercises of reflexivity and creativity in the reception of works commonly identified as products of the so called mass culture . This path allows us, in the steps of Nestor Garcia Canclini, researcher in reception within Latin-American context, create and, somehow confirm the hypothesis that consume is also useful for thinking . In order to get to this result, we have carried out a camp research that used instruments and techniques both quantitative and qualitative. After the data analysis we came to the conclusion that consume of movies taken as commercial type and as not very noble in the environment of cultural production, also impels exercises of creativity and social reflexivity

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La tesis parte del presupuesto que el cine ofrece la imensa capacidad de entretejer de forma compleja realidad e imaginación. Con eso sugerimos que tal cual una "escuela de vida", según la definición de Edgar Morin (2003), el cine, por medio de sus producciones y exibiciones, pude ser capaz de operar un movimiento de reinvención de una estética del vivir en el espacio de lo improbable. De ahi surge la pregunta: ¿Cómo un fenómeno artístico, estético e imagético puede realizar tal movimiento? Tomando como referencia el guión de vida del personaje de la vida real José Isaias de Lucena Filho, más conocido por Zezeco, encontramos pistas de esa reinvención. Residente de una pequeña ciudad del interior de la província de Rio Grande do Norte, llamada Ouro Branco, en la década del 1960, se desplazó hacia el centro-sur de Brasil y retornó a su lugar de partida con la idea de trabajar proyectando peliculas. De manera singular y plural, este sujeto asumió el riesgo y la incertidumbre de enfrentar determinismos sociales, climáticos y culturales para proponer nuevas simbolizaciones por medio del cine itinerante. La presencia del séptimo arte en pequeñas ciudades de hábitos rurales marcadas por la miséria, el hambre, la negligéncia, el coronelismo político y los problemas climáticos, alteró escenários, actualizó mitos y proporcionó nuevas interacciones entre los sujetos. Zezeco entró en las cifras del éxodo rural y emigró hacia Rio de Janeiro, pero su éxodo fue cinematográfico, porque le sirvió como base para la inserción de efectos especiales fantásticos y poéticos en guiones de vidas inmersas en lo trivial y lo contingente. Tal cual un cinematógrafo vivo, capturó el escenário cultural efervescente de Rio de Janeiro y lo proyectó en la pequeña ciudad de Ouro Branco y en otras ciudades del interior de las províncias de Rio Grande do Norte y Paraiba. Con ello le atribuyó un nuevo uso a la vida de su lugar de partida y de retorno. Actuó en la ambiguedad, la ambivalencia y la complejidad entre el sapiens e el demens; real e imaginario; prosa y poesia de la vida; razón y pasión; racional y simbólico; lógico y mítico. El alcance de la investigación contempla entrevistas, memória, registros manuscritos y fotografías de colección particular de habitantes de la ciudad de Ouro Branco-RN. Como referenciales teóricos principales, tenemos las obras de Edgar Morin sobre el cine y de otros autores como Giorgio Agamben y Maria da Conceição de Almeida que expanden la comprensión sobre el entreejido de realidad e imaginación, vida e ideas

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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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This project goes beyond the interfacial field of cinema, History and education. We take as our object the epistemological potential of the cinema at the educational scenario, specifically the use of films integrated to the practices of History teachers and educative processes in which we have taken part as a builder. Our objective is to map, initially, the knowledge around this use to search a synthesis and its empirical application. From the methodological point of view, we have made use of different perspectives: (a) interviews with the educator subjects; (b) observation of their practices and formative circumstances; (c) filmic analysis and the relation of the cinema s epistemology with the other areas ones (initially History and further Journalism). Our analysis allowed us to portrait the film such as an epistemological-troubling category, what makes the cinema rather a builder technology and not simply a complementary and illustrative technological resource. Therefore, we have realized that the restriction to the cinema s educational function is linked to the restrictions to the theoretical categories to an only interfacial aspect: historical film as a film which portraits the past (at the historical field) and film on journalism as a film which approaches a single object of Journalism (at the journalistic field). These discussions happen, consequently, at the arena of the nature of cinema s genres (fiction and documentary), which are understood in a naïve way, simpler than its epistemological possibilities, boosted at this research when we analyze the confluence between fiction and reality. The reflections on educative practices and in formation related to the cinema had occurred in three empirical realities: research with professors in performance, practices docent s and accompaniment of students of history. Have to do with our personal career as a teacher and researcher and, when analyzed other practices, have become, unavoidably, the subject and object of this project

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The investigation about the body consciousness in school Physical Education had as main objective reporting a possibility of intervention, linking it directly to the contents of Physical Education and considering it as a crosscutting theme in this research. In this scope, we worked specifically with two contents of Physical Education - knowledge about the body and fights. During the study, we are going to discuss about teaching strategies for the themes of body awareness. To develop this work, we used the following study questions: how is treated the body consciousness in Physical Education and how it has been addressed in educational interventions? What are the difficulties found to the themes of body awareness on different issues of school Physical Education? How body awareness thematized in contents in Physical Education is received by the students and what are the attitudes demonstrated by them during the development of these lessons? Based from questions of study, we used the following methodological tools: participant observation, interviews, photographic records, debates, films, dramatizations and dynamics, which they were performed to stimulate students' critical thinking about their body and the other children s one. The research with ethnographic characteristics was conducted in two schools: one elementary school I, in Natal and one elementary school II, held in the municipality of the João Câmara, in the state of Rio Grande do Norte. We developed a structure in order that the three dimensions of contents conceptual, procedural and attitudinal were experienced by students. The work is structured in five chapters. At first, we made an introduction to justify the motivations that led us to write about body awareness at school. In the second chapter, we discussed reflection about the body and its possibilities of understanding, reflecting on the body and how this awareness was being treated in physical education classes at school. In the third chapter, dealing with the body awareness and dialogue with the Physical Education, we had made a theoretical approach, from authors such as CLARO (1988), NÓBREGA (2000), ARAGÃO (2004), MELO (2006), LORENZETTO and MATTHIESEN (2008) in order to situate the body consciousness and its relationship with physical education. In the fourth chapter, we talked about body awareness thematized in physical education contents: knowledge about the body and fights. We introduced the teaching experience developed in the school and we discussed with authors such as OLIVIER (2000), DARIDO AND RANGEL (2008), among others, about how was the reflection about the body leaving of these experiences. The fifth chapter was intended to closing remarks, in which we concluded that the body awareness, treated in physical education in school by sociocultural and historical aspects, it will contribute in building a man, a body and a society. Although the body consciousness is crafted in a few moments of Physical Education, based on the practices of body awareness or alternatives; in our proposal, we pointed out another perspective to work with body awareness, bringing its elements to permeate and pass through the contents of Physical Education. At work we can see a suggestion for that these experiences are carried out by other Physical Education professionals, obviously adapting the activities according to age and educational level of students

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Cette étude présente l anthropophagie comme une notion théorique et experiementale du corps qui réhabilite le sensible et réveille le monde perçu. L argumentation fait ressortir la dimension sensible du corps et de la connaissance, en considerant sa sensibilité et motricité, corps qui ne se sépare pas de la nature et de l histoire, en actuant dans le monde comme présence vive, originaire, en mouvement ; en supposant un sujet qui, au même temps que construit ses propres senses, il dépend de l expérience de l autre et du monde, en créant et en recréant la culture, et il agrandit le processus de connaître, de sentir, de penser, d agir, d être, de se transformer. Cette attitude annonce une connaissance sensible et un corps qui est suscetible de sensations, mais d expréssions aussi, de communication, de création, aspects indispensables pour se pensar l éducation comme un space sensible, d apprantissage et réssignification de la culture ; que dévient possible la communion avec le corps, le temps, le space ; qu enseigne à réapprendre à voir le monde, que considère la réversibilité des senses et l esthésie comme champs de l expérience sensible et de l imputation des senses ; qu évoque la beauté des multiples léctures du vécu et qu agrandit la compréhension du soi et de l autre. L objectif de ce travail est comprendre l anthropophagie comme une attitude du corps et de la connaisance sensible, qu approfondit la rélation de l être au monde, la rélation avec l autre et permet la création de senses culturelles, ésthetiques et éxistentielles our l éducation. Nos présentons l attitude phénomologique de Maurice Merleau-Ponty comme référence théorique et méthodologique de notre recherche. Il s agit d une attitude de la pensée qui place la conaissance au centre de nos expériences vécues au monde ; une attitude qui ne propose pas un sens définitif des choses et des personnes et qui contribue pour la compréhension de l anthropophagie, du corps, du sensible, du monde et de l autre, en indiquant des développements de ces réflexions pour l éducation. En créant des horizonts de sense et strastégies de pérception sur l anthopophagie, nos considérons comme choix notre expérience vécu, comme les voyages; atelier d extension avec des élèves du cours de Technologie en Production Culturelle de l Institut Fédéral d Éducation, Science et Technologie du Rio Grande do Norte-IFRN, Campus Cidade Alta ; l anthropophagie comme élement de l Art Moderne Brésilien ; les créations et les récits des élèves ; images ; filmes et livres recherchés ; dialogues avec les penseurs Lévi-Strauss, Montaigne et Oswald de Andrade, qui constituent nos principales références conceptuelles et qui ont permis traversé des savoirs et promouvoir un dialogue entre divers champs de connaissance, comme l Anthropologie, la Philosophie, l Art et l Éducation. Ces stratégies constituent le resultat partiel et inachevé d un processus de connaisance de soi et de l autre, que permet de revivre des mémoires, faire ressortir des couleurs, des senses, des goûts, des découvertes sensibles et encourageantes sur la connaissance, sur l art, des découvertes sur soi même, sur l autre, sur le monde, sur la vie, indiquant que l éducation peut être un processus fort sensible, dans lequel le corps est une présence indispensable, aussi comme le toucher, le créer, les delires, les affections, les encontres et l invention