1000 resultados para Matèria condensada


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A recarga artificial de aquíferos (RAQ) com águas residuais tratadas (ART) é uma prática que pode contribuir para a reposição de volumes de água no solo, que pode ser muito vantajoso em áreas com déficit hídrico ou com sobre-exploração de águas subterrâneas. No entanto, as cargas residuais das ART (p.e. matéria orgânica, nutrientes, metais pesados e microrganismos patogênicos) podem constituir uma desvantagem para a qualidade da água subterrânea, se o solo apresentar condições desfavoráveis para a sua infiltração. Realizaram-se ensaios laboratoriais em batelada para avaliar a remoção de matéria orgânica e nutrientes (formas de nitrogênio e fósforo) na componente fina de um solo residual granítico, proveniente de uma zona previamente selecionada para a infiltração de ART, localizada no nordeste da região da Beira Interior (Quinta de Gonçalo Martins, Guarda, Portugal). Os resultados dos ensaios de sorção em batelada mostram uma boa remoção de P-PO4, por complexação e precipitação, o que indica que o solo apresenta capacidade reativa para remover a carga residual de fosfato das ART. Após realização dos ensaios em batelada, as propriedades do solo mantiveram-se praticamente inalteradas.

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Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

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The central theme of this dissertation encompasses the importance of space, particularly the exhibition space, and how it has become part of the subject matter, as well as a medium in art. Some artistic practices of the 20th century, mainly in the 20s and 60s, both in Europe and the United States of America have provided the contextual foundation. The close relation between the architectural and exhibition spaces has become an intrinsic link to establish the existence of the three-dimensional work of art. The overarching importance of space in the contemporary artistic practice is visible through the creative and exhibition installation process, most notably in the artistic movements of Installation art and Site-specific. By carrying over the transformative contemporary art scene concepts to an institutional and museological context, paired with the inherent evolution of its practices, these have allowed for a convergence of the museological fields. With the intention of providing audiences a unique experience, curators and museologists have relied on site-specific practices. By inviting artists (typically featured in the current artistic scene) to develop projects specially thought for a specific museum space, this simultaneously allows for a dialogue between the work of art and the space. These temporary exhibitions have garnered the attention a more diverse audience. As a result sustainability and independence of the museums are a constant source of debate. The result of which has allowed for the broadening of the notions of how museums function and have integrated the audience as a main element of the strategies of the museum programming. The principles of the cultural marketing provide museums a clearer vision of the understanding of the different audience and their needs. Thus, the main goal of this study is to perceive the importance of the museum space in the relation to the artistic practice. While existing as a strategic resource of the museological program, insofar as having the ability to lure new audiences. It also matters to notice, if the fact of the artist working directly inside the museum, contribute to a narrowing of the artist/audience relationship, being the museum the mediation element

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Berkeley’s general tenet about immaterialism is presented and discussed. I examined apart the several theses that concur to the immaterialist theory. After that, the general argument is presented and discussed. In particular, I stress Berkeley’s assumption that a world without matter and a world with matter would be indistinguishable from the point of view of (i) the content of perceptions, (ii) natural science (viz. Newtonian mechanics). I stress that this assumption depends on a relative account of circular motion, generating the centrifugal forces, as Newton shows in his bucket experiment. In spite of the efforts by Leibniz and Huygens, such a relative account of rotational motion was never presented. So the thesis about the scientific and perceptual identity between worlds with and without matter remains a simple case of wishful thinking in need for a justification.

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The present study aims to evaluate the potential use of bagasse ash from sugar cane (CBC) as a flux, replacing phyllite and/or feldspar in standard industrial mass production of enameled porcelain, verifying the possibility of the CBC contribute to the overall reduction of the coefficient of thermal expansion of the ceramic mass. To this end, as a result of the research, we characterized the raw material components of the standard mass (clay, phyllite, kaolin, feldspar, quartz and talc) and the residue of BCC, by testing by XRF, XRD, AG, DTA and ATG. Specimens (CDP) were manufactured in the dimensions of 100 mm x 50 mm x 8 mm in uniaxial matrix under compaction pressure of 33 MPa, assembled in batches of 3 units subsequently sintered at temperatures of 1150°C to 1210°C by varying the Rating Scale at 10°C, heating and cooling ramp of 50°C/min and 25°C/min, with levels of 1 min, 3 min, 5 min, 8 min, 10 min, 15 min, 30 min and 60 min. analyzing the results of the physical properties of water absorption (WA), linear firing shrinkage (LFS), dilatometric analysis (DTA), flexural strain (SFT) and SEM of the sintered bodies in order to verify the adequacy of CDP to ISO 13006, ISO 10545, NBR 13816 standards; NBR 13817 and NBR 13818. The study showed that the formulations that best suit the requirements of the standards are:. G4 - which was applied in 10% of replacing the CBC phyllite, sintering temperature 1210 ° C for 10 min and porch, and F3 - with application of 7.5% of CBC to replace the feldspar in the sintering temperatures of 1190°C, 1200°C and 1210°C for 10 min and porch. These formulations showed better performance regarding the formation of primary and secondary mullite, with considerable reduction of cracks and pores, meeting the prerequisites of standards for glazed porcelain. The results shows that the use of the CBC as a flux in the preparation of porcelain mass meets standard parameters for the manufacture of the product, and thereby can reduce environmental impact and the cost of production. Therefore, it is recommended to use this residue in the ceramics industry, due to its industrial, commercial and collaborative viability for sustainability.

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Dark matter is a fundamental ingredient of the modern Cosmology. It is necessary in order to explain the process of structures formation in the Universe, rotation curves of galaxies and the mass discrepancy in clusters of galaxies. However, although many efforts, in both aspects, theoretical and experimental, have been made, the nature of dark matter is still unknown and the only convincing evidence for its existence is gravitational. This rises doubts about its existence and, in turn, opens the possibility that the Einstein’s gravity needs to be modified at some scale. We study, in this work, the possibility that the Eddington-Born-Infeld (EBI) modified gravity provides en alternative explanation for the mass discrepancy in clusters of galaxies. For this purpose we derive the modified Einstein field equations and find their solutions to a spherical system of identical and collisionless point particles. Then, we took into account the collisionless relativistic Boltzmann equation and using some approximations and assumptions for weak gravitational field, we derived the generalized virial theorem in the framework of EBI gravity. In order to compare the predictions of EBI gravity with astrophysical observations we estimated the order of magnitude of the geometric mass, showing that it is compatible with present observations. Finally, considering a power law for the density of galaxies in the cluster, we derived expressions for the radial velocity dispersion of the galaxies, which can be used for testing some features of the EBI gravity.

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Dark matter is a fundamental ingredient of the modern Cosmology. It is necessary in order to explain the process of structures formation in the Universe, rotation curves of galaxies and the mass discrepancy in clusters of galaxies. However, although many efforts, in both aspects, theoretical and experimental, have been made, the nature of dark matter is still unknown and the only convincing evidence for its existence is gravitational. This rises doubts about its existence and, in turn, opens the possibility that the Einstein’s gravity needs to be modified at some scale. We study, in this work, the possibility that the Eddington-Born-Infeld (EBI) modified gravity provides en alternative explanation for the mass discrepancy in clusters of galaxies. For this purpose we derive the modified Einstein field equations and find their solutions to a spherical system of identical and collisionless point particles. Then, we took into account the collisionless relativistic Boltzmann equation and using some approximations and assumptions for weak gravitational field, we derived the generalized virial theorem in the framework of EBI gravity. In order to compare the predictions of EBI gravity with astrophysical observations we estimated the order of magnitude of the geometric mass, showing that it is compatible with present observations. Finally, considering a power law for the density of galaxies in the cluster, we derived expressions for the radial velocity dispersion of the galaxies, which can be used for testing some features of the EBI gravity.

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This paper evaluate the performance of a Wastewater Treatment Plant (WWTP) in sequential batch activated sludge modality with tertiary treatment step, located in high temperature region. It also presents the analysis of organic matter’s removal and the evaluation of sludge sedimentation conditions through reactors in bench scale, fed with different substrate’s and biomass’ concentrations, from the WWTP in study. The results showed high efficiency and stability of the treatment process using Sequential Batch Reactors for domestic sewage, even with sudden changes of organic and hydraulic load, reaching more than 90% of efficiency in the removal of biodegradable organic matter. The removal of organic matter and sedimentation tests in bench reactors showed the good performance in respect of the organic matter’s removal, however, the high concentration of micro-organism results in a lower sludge sedimentation rate, which can compromise the quality of the final effluent. The relation Food/Microorganism in the conditions of the WWTP’s current operation showed a value of 0.06 gCOD/gVSS.d. and zonal sedimentation velocity of 0.59 m/h, the great ratio of the concentration of the substrate by biomass concentration, which obtained the maximum operational efficiency, showed a value of 0.09 gCOD/gVSS.d. and zonal sedimentation velocity of 1.4 m/h.

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This paper evaluate the performance of a Wastewater Treatment Plant (WWTP) in sequential batch activated sludge modality with tertiary treatment step, located in high temperature region. It also presents the analysis of organic matter’s removal and the evaluation of sludge sedimentation conditions through reactors in bench scale, fed with different substrate’s and biomass’ concentrations, from the WWTP in study. The results showed high efficiency and stability of the treatment process using Sequential Batch Reactors for domestic sewage, even with sudden changes of organic and hydraulic load, reaching more than 90% of efficiency in the removal of biodegradable organic matter. The removal of organic matter and sedimentation tests in bench reactors showed the good performance in respect of the organic matter’s removal, however, the high concentration of micro-organism results in a lower sludge sedimentation rate, which can compromise the quality of the final effluent. The relation Food/Microorganism in the conditions of the WWTP’s current operation showed a value of 0.06 gCOD/gVSS.d. and zonal sedimentation velocity of 0.59 m/h, the great ratio of the concentration of the substrate by biomass concentration, which obtained the maximum operational efficiency, showed a value of 0.09 gCOD/gVSS.d. and zonal sedimentation velocity of 1.4 m/h.

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In view of the climate of instability and deep social inequalities, it has been evident in the Brazilian reality, a new way to punish systematic already developed and consolidated in other countries, in which, among other things, the criminality is anticipated only by danger that the individual sports. It appears, therefore, that the theory developed by Günter Jakobs, nominated Criminal Law of the Enemy, became subtly inserted in the Brazilian reality as well as in international relations signed. In this sense, the Brazilian State, in order to carry out the international legal cooperation in the criminal field, signed a mutual assistance agreement with the government of the United States of America. Forward the conclusion of Mutual legal Assistance Treaty (MLAT), the signatory countries voiced a desire to cooperate in order to facilitate the implementation of tasks of the authorities responsible for law enforcement in both countries, comprising research, investigation, prosecution and prevention of crime, said internalized adjustment in the Brazilian legal system by means of Decree No. 3810 of 02 May 2001. Alongside these considerations, the present study aims to analyze the Criminal law of the Enemy today, seeking to find evidence of that theory in the MLAT, international legal cooperation instrument signed between the government of the Federative Republic of Brazil and the government of the United States of America. Moreover, it has the objective to describe its effects on the Brazilian jurisdiction, especially as concerns the relativity and the suppression of human rights. Once done the introit, analysis will be carried out in the first chapter, on the definition and main features of the theory of Criminal Enemy of the law, it is imperative to approach the humanistic aspect that preceded the theory as well as the dealings given to some controversial issues surrounding it, such as the anticipation of the enemy's punishment and the disproportionality of the penalties imposed. In the second chapter will present the conceptual assumptions, historical evolution and the positives aspects, as well as the barriers and the pursuit of effectiveness of international legal cooperation. In the chapter, bedroom effective analysis of specific modality of cooperation will be held, the Mutual legal Assistance Treaty - MLAT in criminal matters, signed between the Federative Republic of Brazil and the United States of America, in which the general aspects will be addressed and the MLAT reflections on the Brazilian jurisdiction, which includes analysis about the relativity or suppression of human rights, future trends and creating stricter laws, followed by the presentation of the seized conclusion on the subject, in which, among other approaches, will be voiced understanding about the unconstitutionality certain service requests that, from these, there is the bad use of the agreed instrument.

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Organo-mineral fertilizers have been used to both meet plants’ nutritional needs and reduce producers’ reliance on mineral fertilizers. This practice improves both the use of nutrients by plants and the soil structure due to the organic matter in these fertilizers. This study aimed to determine the effect of organic matter sources in the composition of organomineral fertilizers and compare it to the effect of traditional mineral fertilizers when it comes to the initial development of sorghum. Research was carried out in a greenhouse at the Federal University of Uberlandia, in Uberlandia, Minas Gerais, Brazil. Sorghum seeds of grain-bearing simple hybrid 1G100 were used in the seeding process. The experiment followed a randomized complete block design in a 4 x 3 + 2 factorial arrangement. Factors included four levels (50, 75, 100 and 125% of 450 kg ha-1, which is the recommended dose for sorghum crops), three organic matter sources in the composition of the organomineral fertilizers (sewage sludge, filter cake, and peat), a control (100% mineral fertilizer), and an untreated check (no fertilizers). Each experimental plot consisted of four plants divided into two pots. Oxisol was used in all pots. Analyses were performed at 30 and 60 days after seeding (DAS) and targeted: plant height, stem diameter, chlorophyll A, chlorophyll B, and leaf area. After this period, plants were removed from the soil, and had their aerial parts isolated to be dried in an air-forced oven before measurement of their dry mass. Means of the organomineral fertilizers outperformed those of both control and untreated check plots in almost all variables at 30 DAS. The only exception was variable stem diameter, in which organomineral fertilizers outperformed untreated check plots only. Sorghum fertilized with organomineral fertilizers also showed positive results in the variables analyzed at 60 DAS: even with dose reduction, their means were similar to those found in control plots. Organomineral fertilizers had higher means in some variables, such as diameter and dry mass of the aerial part, than both control and untreated check plots. In the conditions set in this study and considering the variables herein reported, organomineral fertilizers can substitute mineral fertilizers in the initial development of sorghum, even with some dose reductions.

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The animal trampling favors the soil compaction process in sheep raising and crop production integrated systems. This compression has negative effects, hindering the development of roots, the availability of nutrients, water and aeration, causing production losses, making it essential for the assessment of soil physical attributes for monitoring soil quality. Soil organic matter can be used to assess the quality of the soil, due to its relationship with the chemical, physical and biological soil properties. Conservation management system with tillage, along with systems integration between crops and livestock are being used to maintain and even increase the levels of soil organic matter. For that, a field experiment was carried out over a Oxisol clayey Alic in Guarapuava, PR, from de 2006 one. experiment sheep raising and crop production integrated systems The climate classified as Cfb .. The study was to evaluate the soil physical properties and quantify the stock of soil organic carbon and its compartmentalization in system integration crop - livestock with sheep under four nitrogen rates (0, 75, 150 and 225 kg ha-1) in the winter pasture, formed by the consortium oat (Avena strigosa) and ryegrass (Lolium multiflorum) and the effect of grazing (with and without). The soil samples blades density evaluations, total porosity, macro and micro, aggregation and carbon stocks were held in two phases: Phase livestock (after removal of the animals of the area) and phase crop (after maize cultivation). The collection of soil samples were carried out in layers of 0-0.5, 0.05-0.10, 0.10-0.20 and m. Data were subjected to analysis of variance and the hypotheses tested by the F test (p <0.05). For the quantitative effect data regression and the qualitative effect used the test medium. In non-significant regressions used the average and standard deviation treatments. The animal trampling caused an increase in bulk density in the 0.10-0.20 m layer. The dose of 225 kg N ha-1 in winter pasture increased total soil porosity at 8% compared to dose 0 kg N ha-1 in the crop stage. The grazing had no effect on soil macroporosity. GMD of aggregates in the phase after grazing the surface layer was damaged by grazing. Nitrogen rates used in the winter pasture and grazing not influence the total organic carbon stocks. The TOC is not influenced by nitrogen fertilization on grassland. The grazing increases the stock of POC in the 0.10-0.20 m layer livestock phase and cause the stock of POC in the 0-0.5 m layer in the crop stage. The MAC is not influenced by N rates applied in the pasture or by grazing.

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O trabalho teve por objetivo caracterizar o estoque de anchoita (Engraulis anchoita) capturado na região sul do Brasil, visando à utilização deste recurso de alto valor biológico no desenvolvimento de produtos semi-prontos e de fácil preparo, tipo empanado. Os experimentos foram conduzidos com anchoita resultante de cruzeiros realizados pelo Navio Oceanográfico Atlântico Sul da Universidade Federal do Rio Grande (FURG), RS, Brasil. Os exemplares foram capturados entre a cidade de Rio Grande (32ºS, RS-Brasil) e 51ºW. Após captura, o pescado foi armazenado a bordo em mistura de gelo e água do mar, na razão 1:1. As amostras foram transportadas para o laboratório de Biotecnologia da FURG e mantidas sob congelamento a -18°C, até a realização das análises. O trabalho está constituído por uma revisão bibliográfica, que enfatiza a importância do recurso pesqueiro em estudo como potencial a ser explorado, discorre sobre ácidos graxos e perfil de voláteis, bem como, o desenvolvimento de produtos à base de pescado. O desenvolvimento do trabalho é expresso por quatro artigos. O primeiro teve como objetivo caracterizar o estoque de anchoita segundo a biometria, rendimento, composição proximal, compostos nitrogenados e ácidos graxos. O rendimento, a composição proximal e o perfil de ácidos graxos foram realizados nas três frações que compõe o peixe: músculo claro, escuro e vísceras. A análise dos resultados demonstrou a variabilidade dos componentes em função das frações avaliadas e da época de captura, o que pode contribuir para a escolha do processo tecnológico a ser aplicado no desenvolvimento de produtos de alto valor agregado a partir dessa matéria-prima. No segundo artigo foi determinado o perfil de ácidos graxos da anchoita e avaliado o comportamento destes compostos durante o armazenamento congelado, bem como, dos voláteis gerados. Os resultados demonstraram a influência do armazenamento na modificação dos ácidos graxos, em especial, EPA e DHA, e que os voláteis gerados podem ser um índice em potencial para avaliar a qualidade da anchoita congelada. No terceiro artigo objetivou-se selecionar e treinar julgadores para avaliação do odor a pescado utilizando os padrões referência obtidos a partir do perfil de voláteis. Neste sentido, foi levantada a terminologia que descreve o odor da anchoita, definido padrões referência, bem como, selecionado e treinado uma equipe de julgadores. Foram utilizados 20 candidatos, deste total, 9 foram selecionados pelo método das amplitudes. Os julgadores selecionados foram submetidos ao treinamento no uso de escala não estruturada e na avaliação da intensidade do odor a pescado. O desempenho dos julgadores foi definido utilizando como amostra solução de lavagem resultante do processo de obtenção de base protéica de anchoita. Os resultados foram avaliados com base no poder de discriminação, repetibilidade das respostas e concordância entre julgadores, segundo análise de variância, com duas fontes de variação (amostra e repetições). Foram obtidos os valores de Famostra e Frepetição, para cada julgador. Os julgadores com o valor de Famostra significativo (p≤0,30) e Frepetição não significativo (p>0,05), bem como, concordância de médias com os demais julgadores foram considerados treinados. Segundo esse processo a equipe foi constituída por 8 julgadores selecionados e treinados na avaliação do odor a pescado. Finalmente, no quarto artigo foi avaliada a possibilidade de uso de base protéica (BPP) de anchoita na elaboração de massa base de empanados, bem como, em substituição a farinha de cobertura. Para obtenção das BPPs, foram testadas duas soluções extratoras (3 ciclos de extração com ácido fosfórico 0,05% e 1 ciclo de ácido fosfórico seguido de 2 ciclos com água). A BPP obtida na melhor condição utilizada foi seca a 70°C e submetida ao processo de moagem em moinho de facas para ser utilizada como farinha de cobertura. Formulações de empanado utilizando diferentes concentrações (25, 50, 75 e 100%) de anchoita desidratada na cobertura foram testadas no produto frito e forneado. Um teste de preferência com consumidores em potencial foi aplicado às diferentes formulações. Os resultados indicaram que a melhor condição de lavagem para obtenção das BPPs testadas foi quando são utilizados 3 ciclos de extração com ácido fosfórico. A avaliação da preferência junto ao consumidor em potencial demonstrou que a anchoita desidratada pode ser utilizada como farinha de cobertura em empanados na concentração de até 75%.

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Dissertação de Mestrado, Ciências Económicas e Empresariais, 8 de Julho de 2016, Universidade dos Açores.

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O presente estudo analisa a associação entre partículas inaláveis (PM10) à superfície e determinadas situações meteorológicas, com base em dados (1999-2003) de concentração de partículas finas e grosseiras de estações de qualidade do ar da região de Lisboa e observações meteorológicas. Associaram-se os episódios de poluição a situações sinópticas, com base em cartas de superfície do modelo do Centro Europeu de previsão a médio prazo (ECMWF). Os episódios que ocorrem com maior frequência no Inverno estão associados a um anticiclone. Depressões de origem térmica e vales que se estendem do Norte de África ocorrem poucas vezes, mas a probabilidade de se verificar um episódio com essas situações é elevada. Para cinco destes episódios analisaram-se campos do modelo ECMWF (escala sinóptica) e do modelo ALADIN (mesoscala). As elevadas concentrações de partículas associadas aos episódios estudados resultaram de uma forte influência do nível850 hPa, corroborados pelo modelo de retro-trajectórias do KNMI. ABSTRACT; The present study analyses the relationship between particles (PM10) and specific meteorological patterns based on fine and coarse particles concentration data (1999 to 2003) from the Lisbon area air quality network and meteorological observations. Associations were established between PM10 events and synoptic patterns based on surface fields from European Centre for Medium-Range Weather Forecast (ECMWF) Model. Winter events occur mainly under high pressure conditions. Thermal lows and troughs over North Africa affecting the lberian Península occur less frequently; however, the probability of a PM event with this synoptic pattern is high. Meteorological fields from the ECMWF model (synoptic scale) and the ALADIN model (mesoscale) were analyzed for five of these episodes. The 850 hPa level is quite relevant for determining high PM10 concentrations at the surface, as confirmed by KNMI trajectory model.