1000 resultados para Modernização seletiva
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The main objective of this work is to optimize the performance of frequency selective surfaces (FSS) composed of crossed dipole conducting patches. The optimization process is performed by determining proper values for the width of the crossed dipoles and for the FSS array periodicity, while the length of the crossed dipoles is kept constant. Particularly, the objective is to determine values that provide wide bandwidth using a search algorithm with representation in bioinspired real numbers. Typically FSS structures composed of patch elements are used for band rejection filtering applications. The FSS structures primarily act like filters depending on the type of element chosen. The region of the electromagnetic spectrum chosen for this study is the one that goes from 7 GHz to 12 GHz, which includes mostly the X-band. This frequency band was chosen to allow the use of two X-band horn antennas, in the FSS measurement setup. The design of the FSS using the developed genetic algorithm allowed increasing the structure bandwidth
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Particularly in Braziland in Rio Grande do Norte, companies manufacturing red ceramic, play an important role as agents of development to study the region Seridó- RN, specific place for carrying out the research. It is observed in this region a concentration of red ceramic industries of small size, which, despite its importance in the ceramic, they are unable to enjoy or use the new forms of administrative management and technological advances designed and offered by universities, centers of research and projects of governments, remained almost entirely outside the progress and modernization, technological and administrative. These companies still have outdated technology, and management processes, providing quality problems and standardization of end products. Upon these conditions are the companies going through crisis and struggling to survive alone and without assistance. The region of Seridó-RN, lets make a detailed case study of red ceramic companies in the region proposed from the existing theoretical and actual lifting of the condition of the product manufacturing red ceramic, allowing through this overview of the implementation of collect samples of raw materials, allowing the study of each ceramic industry that contributed to the participation of the research, which was determined parameters such as: analysis of the physical, chemical and technological properties of raw materials, characterization of the processes used, raising the technological resources considering equipment, machinery, supplies, raw materials and facilities available and its organization by type of products from companies involved in this study. The methodology consists of the following steps: collection of raw material, crushing and screening, characterization of raw materials (liquid limit, chemical analysis, mineralogical analysis, differential thermal analysis, sieve analysis), mixing, forming, cutting, drying and burning of ceramic bodies and bodies of evidence. The results showed that it was clay with distinct characteristics with respect to plasticity. With respect to the different compositions of mixtures of ceramic masses, we conclude that the ceramic properties showed a direct proportionality with increasing fraction of the clay not plastic. However, the compositions of the masses studied proved to be the most appropriate for the types of simulated clay for use in ceramics. Adopted in the ceramic processing made it possible to obtain products the resulted in consistent properties, and in some cases even exceeding the requirements of technical studies and standard-Brazilian clays to obtain ceramic products such as tiles, bricks and tiles to floor. Based on the discussions from the results obtained in the various processing steps of this work, one can draw conclusions according to the physico-chemical and mineralogical properties of raw materials, the properties of ceramic products burned and analysis. This work may be used by other researchers, private companies and governmental organizations, undergraduate students and graduate, can develop studies and future research to: develop projects to modify the furnaces; mapping projects develop and rationalize the exploitation of raw materials ;promoting reforestation and forest management; develop reduction projects and recovery of waste; develop training projects in manpower sector, and develop security projects, improving the conditions of work in the area pottery
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The topology optimization problem characterize and determine the optimum distribution of material into the domain. In other words, after the definition of the boundary conditions in a pre-established domain, the problem is how to distribute the material to solve the minimization problem. The objective of this work is to propose a competitive formulation for optimum structural topologies determination in 3D problems and able to provide high-resolution layouts. The procedure combines the Galerkin Finite Elements Method with the optimization method, looking for the best material distribution along the fixed domain of project. The layout topology optimization method is based on the material approach, proposed by Bendsoe & Kikuchi (1988), and considers a homogenized constitutive equation that depends only on the relative density of the material. The finite element used for the approach is a four nodes tetrahedron with a selective integration scheme, which interpolate not only the components of the displacement field but also the relative density field. The proposed procedure consists in the solution of a sequence of layout optimization problems applied to compliance minimization problems and mass minimization problems under local stress constraint. The microstructure used in this procedure was the SIMP (Solid Isotropic Material with Penalty). The approach reduces considerably the computational cost, showing to be efficient and robust. The results provided a well defined structural layout, with a sharpness distribution of the material and a boundary condition definition. The layout quality was proporcional to the medium size of the element and a considerable reduction of the project variables was observed due to the tetrahedrycal element
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At the cashew nut processing industry it is often the generation of wastewaters containing high content of toxic organic compounds. The presence of these compounds is due mainly to the so called liquid of the cashew nut (CNSL). CNSL, as it is commercially known in Brazil, is the liquid of the cashew nut. It looks like an oil with dark brown color, viscous and presents a high toxicity index due to the chemical composition, i.e. phenol compounds, such as anacardic acid, cardol, 2-methyl cardol and monophenol (cardanol). These compounds are bio resistant to the conventional treatments. Furthermore, the corresponding wastewaters present high content of TOC (total organic carbon). Therefore due to the high degree of toxicity it is very important to study and develop treatments of these wastewaters before discharge to the environmental. This research aims to decompose these compounds using advanced oxidative processes (AOP) based on the photo-Fenton system. The advantage of this system is the fast and non-selective oxidation promoted by the hydroxyl radicals (●OH), that is under determined conditions can totally convert the organic pollutants to CO2 and H2O. In order to evaluate the decomposition of the organic charge system samples of the real wastewater od a processing cashew nut industry were taken. This industry was located at the country of the state of Rio Grande do Norte. The experiments were carried out with a photochemical annular reactor equipped with UV (ultra violet) lamp. Based on preliminary experiments, a Doehlert experimental design was defined to optimize the concentrations of H2O2 and Fe(II) with a total of 13 runs. The experimental conditions were set to pH equal to 3 and temperature of 30°C. The power of the lamps applied was 80W, 125W and 250W. To evaluate the decomposition rate measures of the TOC were accomplished during 4 hours of experiment. According to the results, the organic removal obtained in terms of TOC was 80% minimum and 95% maximum. Furthermore, it was gotten a minimum time of 49 minutes for the removal of 30% of the initial TOC. Based on the obtained experimental results, the photo-Fenton system presents a very satisfactory performance as a complementary treatment of the wastewater studied
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This work aims at the implementation and adaptation of a computational model for the study of the Fischer-Tropsch reaction in a slurry bed reactor from synthesis gas (CO+H2) for the selective production of hydrocarbons (CnHm), with emphasis on evaluation of the influence of operating conditions on the distribution of products formed during the reaction.The present model takes into account effects of rigorous phase equilibrium in a reactive flash drum, a detailed kinetic model able of predicting the formation of each chemical species of the reaction system, as well as control loops of the process variables for pressure and level of slurry phase. As a result, a system of Differential Algebraic Equations was solved using the computational code DASSL (Petzold, 1982). The consistent initialization for the problem was based on phase equilibrium formed by the existing components in the reactor. In addition, the index of the system was reduced to 1 by the introduction of control laws that govern the output of the reactor products. The results were compared qualitatively with experimental data collected in the Fischer-Tropsch Synthesis plant installed at Laboratório de Processamento de Gás - CTGÁS-ER-Natal/RN
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This dissertation aims the development of an experimental device to determine quantitatively the content of benzene, toluene and xylenes (BTX) in the atmosphere. BTX are extremely volatile solvents, and therefore play an important role in atmospheric chemistry, being precursors in the tropospheric ozone formation. In this work a BTX new standard gas was produced in nitrogen for stagnant systems. The aim of this dissertation is to develop a new method, simple and cheaper, to quantify and monitor BTX in air using solid phase microextraction/ gas chromatography/mass spectrometry (SPME/CG/MS). The features of the calibration method proposed are presented in this dissertation. SPME sampling was carried out under non-equilibrium conditions using a Carboxen/PDMS fiber exposed for 10 min standard gas mixtures. It is observed that the main parameters that affect the extraction process are sampling time and concentration. The results of the BTX multicomponent system studied have shown a linear and a nonlinear range. In the non-linear range, it is remarkable the effect of competition by selective adsorption with the following affinity order p-xylene > toluene > benzene. This behavior represents a limitation of the method, however being in accordance with the literature. Furthermore, this behavior does not prevent the application of the technique out of the non-linear region to quantify the BTX contents in the atmosphere.
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Studies show the great influence of free radicals and other oxidants as responsible for aging and degenerative diseases. On the other hand, the natural phenolic compounds has shown great as antioxidants to inhibit lipid peroxidation and lipoxygenase in vitro. Among these, is highlighted trans-resveratrol ( 3,5,4 `- trihydroxystilbene ) phenolic compound , characterized as a polyphenol stilbene class. The vegetables popularly known as "Azedinha" (Rumex Acetosa) has trans-resveratrol in its composition and from this, the present work aimed to study on the supercritical extraction and conventional extraction (Soxhlet and sequential) in roots of Rumex Acetosa, evaluating the efficiency of extractive processes, antioxidant activity, total phenolic content and quantification of trans-resveratrol contained in the extracts. Extractions using supercritical CO2 as solvent, addition of co-solvent (ethanol) and were conducted by the dynamic method in a fixed bed extractor. The trial met a 23 factorial design with three replications at the central point, with the variable reply process yield and concentration of trans-resveratrol and pressure as independent variables, temperature and concentration of co-solvent (% v/v). Yields ( mass of dry extract / mass of raw material used ) obtained from the supercritical extraction ranged from 0,8 to 7,63 % , and the best result was obtained at 250 bar and 90 °C using the co-solvent 15% ethanol (% v/v). The value was calculated for YCER a flow rate of 1,0 ± 0,17 g/min resulting in 0,0469 CO2 ( g solute / g solvent ). The results of the mass yield varied between conventional extractions 0,78 % ( hexane) and 9,97 % (ethanol). The statistical model generated from the data of the concentration of trans-resveratrol performed as meaningful and predictive for a 95% confidence. GC analysis on HPLC (High Performance Liquid Chromatography), transresveratrol was quantified in all extracts and concentration values ranged between 0,0033 and 0,42 ( mg / g extract) for supercritical extracts and between 0,449 and 17,046 (mg / g extract) to conventional extractions and therefore, the Soxhlet extraction with ethanol for more selective trans-resveratrol than the supercritical fluid. Evaluation of antioxidant (radical method to sequester 2,2- diphenyl-1- picryl - hydrazyl - DPPH) the supercritical extracts resulted in EC50 values (concentration effective to neutralize 50% of free radicals) of between 7,89 and 18,43 mg/mL , while resulting in a Soxhlet extraction with EC50 values in the range of 6,05 and 7,39 mg/mL. As for quantification of the phenolic compounds (Method Spectrophotometer Folin-Ciocalteau) the supercritical extracts resulted in values between 85,3 and 194,79 mg GAE / g extract, whereas values derived from the Soxhlet extract resulted in values between 178,5 and 237,8 mg GAE / g extract. The high antioxidant activity can not be attributed solely to the presence of phenolic compounds, but the presence of other antioxidants in the existing Rumex acetosa
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The city of Natal comprises an area of about 170 km² (65,63 squares miles). The Dunas-Barreiras Aquifer is the most important reservoir of the coastal basin of RN. It is being responsible for the water supplying of about 70% of the population, however, due to the sewage disposal system by cesspools and drains, it is presently affected in a great extent by nitrates contamination. Thus, the present work proposes to research the utilization of contaminated water by nitrates of this fountainhead and find cost of the potable water through the ionic exchange technology. This technology consists in the removal of mineral salts by the exchange of cations for one ion of hydrogen (H+), through the passage of water by cationic resin bed and, secondly, by the exchange of the anions for hydroxyl ions (OH-) through a anionic resin bed. The obtained results have showed the waters derived from fountains, big water holes and shallow wells were microbiologically contaminated, while the waters derived from deep wells (above 70 m 76,58 yards) were free of contamination. Thus, only these ones are suitable to the use of ionic technology. The experiments were conducted with the resin IMAC-HP-555 such as kinetic, thermodynamic, and adsorption by fixed bed studies, being obtained several project variables for the experimental column, as follow: work temperature of 25oC; resin maximum capacity maximum e mean of adsorption ==0,01692 g NO3-1/g R e 0,0110 g NO3-1/g R, respectively. On the experimental column were performed breakthrough tests which pointed for an average ideal average speed of work of 13.2 m / h, with an average efficiency of 45% of adsorption, an optimal concentration of NaCl desorption of 8%, and an ideal desorption time of 80 minutes for the equilibrium conditions of water from the Dunas-Barreiras aquifer. Scale projection for ion-exchange column for denitrification, for these variables, using a computer modeling programme, to project the column of ion exchange ROREX-420/2000, obtained a cost for the drinking water denitrified by this system of R$ 0,16 / m3
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Nesta pesquisa estabeleceu-se como objetivo geral analisar a gestão dos resíduos sólidos domiciliares gerados nas cidades de Tarumã e Teodoro Sampaio-SP, com a finalidade de propor ações para o gerenciamento integrado dos resíduos sólidos urbanos. Foram investigados a geração, o tratamento e a destinação dos resíduos sólidos domiciliares, além daqueles gerados no processo de produção da Usina de Açúcar e Álcool Nova América, e sua participação na vida econômica da Usina de Triagem e Compostagem de Tarumã. Esta pesquisa permitiu compreender a importância de uma gestão integrada dos resíduos sólidos visando a combater e minimizar impactos ambientais associados aos mesmos, bem como enfatizar a necessidade de articular a usina de triagem de resíduos sólidos domiciliares com a coleta seletiva em Tarumã e viabilizar a coleta seletiva em Teodoro Sampaio, garantindo assim, ganhos sociais, operacionais, econômicos, educacionais e ambientais para os municípios.
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This work treats about the speeches that produced the crisis of symbols of Ceará, researching on matters and ways of expression of space between 1950s and 1970s. Therefore, we search discursive practices that since the end of nineteenth century built the identity of Ceará and in the middle of twentieth century produced the crisis of modes of seeing and telling the space in front of enunciations of the national modernization, especially with the emergence of politics by SUDENE to the Northeast, the progressive actions by Catholic Church, the defense of tradition by regional literature of union of Ceará Clã. The contradictions between the glorification and fear the modernization of Brazil produced on the space speeches that his identity would be fractured, that the old symbols of drought, cangaço, mysticism and colonels declined. Among analyzed speeches, we centered the analysis of Trilogia da Maldição formed of novels O Dragão, of 1964, Os Verdes Abutres da Colina and João Pinto de Maria: a biografia de um louco by José Alcides Pinto. In this novel, the enunciation of the crisis of symbologies about the space produced another aesthetic, the allegory, which, mixed with the mystical and melancholy, in search of ways to restore the language of the old themes Ceará, drop of Ceará the same stigma of anti-modern space, where the images of delay changed icons of a fractured identity in front of the modern streams, where the word was transformed in the dimension precarious and redeemer of the tradition, of old, of nature, of the plenitude of senses. In Jose Alcides, the colonel returns as the origin of the lost space, the drought is the revolt of God against the devil place, the apocalypse, the end imminent threat to the village, signs that fantastic, however, are in dialogue with the settings space and time in which they were produced
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Dans les premières décennies du XXème siècle, un groupe d intellectuels brésiliens a pris pour soi la mission de conduire la nation aux chemins du progrès, en réfléchissant sur les transformations des villes et, souvent, en proposant et en mettant en avant des actions et mesures qui dirigeraient la modernisation du pays. Dans ce contexte, la ville apparaissait comme un synonyme de progrès en opposition à la campagne, en donnant emphase à la construction du Brésil urbain. À Natal, celui-ci a été une période de sensible modification dans l espace urbain, en suivant les préceptes de l hygiénisme et de l esthétique racionaliste, qui ont orienté les réformes entreprises dans beaucoup de villes brésiliennes. Les élites politiques et socioéconomiques de la capitale du Rio Grande do Norte ont developpé le discours en faveur de la modernisation qui avait pour objectif de justifier les interventions dans la ville et l introduction de l infra-structure de services urbains, par exemple, les services d illumination et de transport, qui à partir de 1911, ont commencé à être stimulés par l électricité. Cette modernisation est matérialisée par de nouveaux équipements et services, par des espaces remodelés en accord avec la rationalité technique de l urbaniste, pour l utilisation de nouvelles sources d énergie (gaz, électricité), en plus de la croissance de la population résidente en ville. Cependant, nous ne pouvons pas oublier que la construction de la ville moderne est passée tant par des transformations physiques, matérielles, comme par l absorption de valeurs, symboles, gestes, vocabulaires, objets, adoptions de nouvelles normes de comportement et par la formation de nouvelles sensibilités sur l espace urbain et la vie en ville. De cette manière, les nouvelles normes technologiques, comme l électricité, ont rendu possible des transformations dans la structure matérielle de la ville et en vie urbaine dans ses plus divers aspects. Ce travail propose d analyser la relation entre énergie électrique et la vie urbaine à Natal entre 1911 et 1940, en prenant en compte, pour cela, les actions d intervention de l État sur l espace urbain et les perceptions d intellectuels face aux transformations urbaines dont ils étaient les témoins. À partir de cette analyse, nous cherchons à préciser les efforts gouvernementaux pour la manutention des services d électricité et conservation des équipements urbains; comprendre comment l utilisation d énergie électrique a aidé à produire de nouvelles situations quotidiennes et comment elle a été perçue, traduite en sentiments et perceptions fondées dans la cohabitation avec cette innovation technique. Les élites locales désiraient diffuser des habitudes considerées modernes, en construisant une identification avec la manière de vie urbaine, fortement inspirée dans la vie dans les villes Européennes et Américaines. L électricité a rendu possible des expériences et sensations qui allaient caractériser l habitant de la ville
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O propósito deste trabalho é analisar as transformações sofridas pelo espaço urbano da cidade do Natal durante a gestão do prefeito Sylvio Piza Pedroza (1946-1950). Neste intuito, nos esforçamos em analisar em que sentido os discursos e as respectivas representações da cidade moderna foram responsáveis pela construção de novos espaços na capital do Rio Grande do Norte, espaços que por sua vez, foram utilizados para justificar duplamente a gestão Piza Pedroza, e o próprio prefeito enquanto exemplos de um momento de modernidade e progresso da cidade. No intuito de responder nosso objetivo, analisamos no decorrer da dissertação três elementos fundamentais para a construção dessa Natal moderna da gestão Piza Pedroza. Dentre eles destacamos as representações construídas pelos jornais natalenses, recifenses e fluminense; a imagem forjada e a relação de legitimação (a partir do espaço da cidade de Natal) possibilitada pela relação entre Câmara Cascudo e Sylvio Pedroza. Por último, analisamos o Arquivo Sylvio Pedroza (ASP), da Fundação José Augusto, percebendo esse suporte como um espaço de inscrição do sujeito e da cidade moderna. Nessa última etapa nos detivemos na apreciação das correspondências e nas fotografias do ASP, percebendo como essas fontes são fundamentais na elaboração e seleção das paisagens modernas da Natal da segunda metade da década de 1940
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Cette dissertation a pour but d´analyser la ville de São Luís do Maranhão pendant la Première Republique, d´après le roman Vencidos e Degenerados, de José do Nascimento Moraes, publié en 1915. À partir des rapports entre l´Histoire et la Littérature, nous nous intéressons à la façon dont l´auteur écrit l´histoire d´une ville qui, après la fin de l´esclavage et l´installation de la Republique, conserve des anciens préjugés de race et reste plongée dans l´immobilité economique. Le roman fait partie d´un ensemble d´oeuvres scientifiques et littéraires d´une géneration connue sous le nom de Novos Atenienses (nouveaux athéniens), laquelle discutait la crise économique et culturelle vécue par le Maranhão au tournant des XIXe et XXe siècles. Le discours formulé par les nouveaux-athéniens comprennait des eléments nostalgiques associés au culte des lettres envisageant la conquête de la réconaissance littéraire et le désir d´adapter la ville de São Luis aux modèles de progrès et modernisation de la période républicaine. Dans ce contexte, Moraes introduit les thèmes liés à la discrimination raciale qui demerait après la fin de l´esclavage, qu´il considérait un obstacle au progrès de la capitale de Maranhão, et aussi la cause des pérsecutions littéraires dont il était victime. On a analisé le roman en cherchant compreendre les rapports entre les individus et les rapports qui´ils entretienent avec les spaces de la ville, à partir de questions d´ordre littéraire, raciale et urbaine. En guise de conclusion, la narration de l´oeuvre est dévellopée de façon que la ville, peuplée de gens de couleurs, sert à legitimée l´oeuvre littéraire de Moraes, dont le nom a été oublié dans les principaux cercles littéraires de la capitale pendant la période examinée
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In Brazil, between the late nineteenth and early decades of the twentieth, polytechnic engineers assumed an important role in discussing the establishment of a modern country. The problem of drought in northeastern Brazil gave the professionals performance, within an interventional process more mounts, the conception plans and measures for the purposeful integration of the territory afflicted. With the foundation of Inspetoria de Obras Contra as Secas (IOCS), in 1909, the actions to combat drought and would be institutionalized, them, studies performed out by technical and scientific committees would be systematically applied in the Brazilian Northeast. So, This work was central objective understand the historical process inplantation of a whole infrastructure of modern character by professional technical and their consequences within the Northeast Geographic space, in specific, in the municipality of Acari in the State of Rio Grande do Norte, in the first half of the twentieth century. The politics of the government, through technical education and scientific engineers polytechnics, would emphasize, during the twentieth century, the building of dams, and irrigation canals, wells, railways, highways, between other elements, that would soon transform the physical space-northeast, specifically, the territory acariense. These works began to contribute to the setting of man backcountry their land, promote the regular practice of agriculture even in periods of drought and, the integration, especially, economic of territory acariense the other producing regions of Rio Grande do Norte and the Northeast as well as promoting the modification of the landscape of the world backcountry. These actions functioned as elements of modernity and progress that transformed the space by favoring by favoring the formation of urban networks (urban) in this space