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The Assessment Of Macroeconomic Variability And Monetary Transmission Mechanisms In Turkey With Var EstimationsBastan, Emine Meltem 01 September 2012 (has links) (PDF)
This thesis investigates the nature of macroeconomic changes by focussing on the monetary policy changes in Turkey between 1990Q1-2011Q4 and assesses the variability of the economy via impulse response functions obtained from VAR analyses. The period of the analyses is characterized with changes of the definitions of monetary aggregates in 2002 and 2007. In order to have consistent monetary series, the new and old series are constructed according to new and old definitions and then analyses are carried out with each type of series and comparisons are given among the monetary series.
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The monetary transmission mechanism in Sri Lanka 1977-1985 : a macro simulation approach to the modelling of the money supply process and the construction of an analytical framework for monetary managementJayamaha, Ranee January 1989 (has links)
The primary objective of this thesis is to analyse the relationship between money and the macro-economy in Sri Lanka between 1977 and 1985, in order to identify the paths through which monetary policy impulses are transmitted over this period. In doing so, - we also hope to highlight the use of macro-simulation as a tool for the analysis of the monetary transmission mechanism and to emphasise the importance of formulating monetary policy within an explicit monetary control framework. This is especially important in Sri Lanka since monetary policy has been a key instrument of demand management since 1977 and historically there has been a noticeable absence of an explicit monetary control framework. Empirical research on the monetary transmission mechanism has been very limited as far as developing countries are concerned. An exception here is the SEACEN (1981) study which simulates the effects of monetary shocks on a number of South East Asian countries, including Sri Lanka, using a flexible monetarist approach. Our research is based upon a revision of the specification of this model for Sri Lanka and a more comprehensive disaggregation of the monetary transmission channels. Our empirical model produces statistical results which are generally acceptable and conform to a Priori expectations. This model is then simulated dynamically, both, to validate the equations in the context of a complete model and to quantify the impact of alternative policy scenarios relating to the monetary transmission mechanism in Sri Lanka. We believe that our results will help to shed light on the nature of the monetary transmission mechanism in developing countries as well as provide the basis for an on-going analysis of monetary management in Sri Lanka.
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Amélioration de la résistance à l'hypoxie des îlots de Langerhans microencapsulés par l’utilisation d’agrégats de cellules disperséesBilodeau, Stéphanie 08 1900 (has links)
La transplantation d’îlots de Langerhans microencapsulés est un traitement prometteur du diabète de type 1. La microcapsule protège l’îlot du système immunitaire, tout en permettant la diffusion de petites molécules. Comme la microcapsule empêche la revascularisation des îlots, leur oxygénation se fait par diffusion d’oxygène et ils sont exposés à l’hypoxie. Le manque d’oxygène est un facteur limitant dans la survie des îlots microencapsulés. Il est connu que les plus petits îlots sont plus résistant à l’hypoxie à cause d’une meilleure diffusion de l’oxygène. À cette fin, les agrégats de cellules dispersées d’îlots seront étudiés. Lorsque les cellules des îlots sont dispersées, elles ont la propriété de se ré-assembler dans une structure semblable à celle des îlots. La présente étude a permis de mettre au point une technique de formation des agrégats, de les caractériser et de comparer la résistance à l’hypoxie des îlots et des agrégats. Ceux-ci ont une structure semblable aux îlots et ils sont de plus petite taille. Pour cette raison, ils sont plus viables après un choc hypoxique tout en renversant efficacement l’hyperglycémie de souris diabétiques. Les agrégats sont une alternative intéressante pour la transplantation d’îlots microencapsulés puisque leur oxygénation est plus efficace. / Transplantation of microencapsulated islets of Langerhans is a promising treatment for type 1 diabetes mellitus. The microcapsule allows the diffusion of small molecules, while protecting the islet from the antibodies and immune cells. However, microcapsule prevents islet revascularization, thus oxygenation depends on diffusion and islets are exposed to hypoxia. Poor oxygenation is a major limitation in microencapsulated islet survival. It was shown that smaller islets are more resistant to hypoxia because of a better oxygen diffusion. In this study, dispersed islet cell aggregates will be used to improve the oxygenation. When islet cells are dispersed into single cells, they have the ability to re-associate into an islet-like structure. This study allowed to set up a technique to form aggregates, to characterized them and to compare the resistance to hypoxia of islets and aggregates. Aggregates have a similar structure than islets and they are smaller. For this reason, they survive better to a hypoxic treatment, while restoring efficiently normoglycemia in diabetic mices. Aggregates are an interesting solution for microencapsulated islet transplantation because they have a better oxygenation.
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Teorie relaxace a přenosu energie v otevřených kvantových systémech / Theory of Relaxation and Energy Transfer in Open Quantum SystemsOlšina, Jan January 2014 (has links)
The work summarizes basic theory of relaxation, energy transfer and decoher- ence in photosynthetic molecular aggregates described as open quantum systems and basic theory of third order coherent non-linear spectroscopy. The work presents two methods for calculation of photo-induced dynamics of molecular aggregates. The methods relax certain approximations of the theories commonly used to model the relaxation and energy transfer in the molecular systems on the sub-picosecond time scale. The first theory derived in the formalism of para- metric projection operators accounts for correlations in a second-order non-linear response-function that are usually neglected in the formalism of master equations. The second theory represents stochastic model of exact dynamics via the cumulant expansion. The work also presents an analysis of importance of the secular and the Markov approximations in the description of dynamics derived in the second-order perturbation theory in the system-bath coupling with emphasis on the excitonic coherence lifetime.
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Variabilidade da agregação em amostras de solos agrícolas como indicador de qualidade: uma proposta metodológica / Variability of aggregation as quality indicator in agricultural soils: a methodological proposalPeche Filho, Afonso 02 March 2018 (has links)
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Previous issue date: 2018-03-02 / As questões ambientais que envolvem os efeitos do manejo e da degradação do solo necessitam de forma acelerada de pesquisa e muita extensão. Novos saberes e conhecimentos têm alcançado parte da comunidade acadêmica, mas ainda está aquém das necessidades para técnicos e leigos envolvidos em trazer soluções para problemas da ocupação, uso e degradação das terras. O manejo e recuperação ambiental de áreas degradadas são complexos e requerem diferentes tecnologias para o diagnóstico e avaliação. O uso de indicadores como diâmetro médio geométrico e distribuição percentual de agregado são parâmetros de uso consolidados, mas trazem limitações para questões complexas como o diagnostico do estado e condição de agregação do solo. A agregação do solo vem sendo estudada desde o inicio do século passado, mas são poucos os avanços conseguidos em popularizar a analise de agregação do solo agrícola como uma ferramenta laboratorial e prática. Além de que, falta conhecimento para popularizar a condição de agregação como informação de uso corrente. O uso de imagens obtidas e processadas em alta resolução permite sua aplicação em diferentes ramos da ciência, podendo ser aplicada nos estudos relacionados com o processo de agregação permitindo viabilizar o mais conhecimento ao processo. Este trabalho tem como objetivo desenvolver uma proposta metodológica para determinar a condição da qualidade de agregação, com base na tipificação de agregados e nos efeitos da variabilidade de composição em amostras de solo agrícola. Foram utilizados parâmetros relacionados com a forma, superfície e biogênese de agregados como indicadores de variabilidade da agregação do solo em duas amostras de latossolo vermelho de textura média, sendo que uma delas é referente a uma parcela de solo que recebeu um produto fertilizante/agregante Microgeo® e outra parcela sem ter recebido o produto. A obtenção dos agregados foi através do processo de peneiramento via seca utilizando cinco peneiras de diferentes calibres. A análise de agregados foi realizada em laboratório a partir de uma sub-amostra contendo 100 agregados oriundos de cada peneira específica, totalizando 500 agregados por amostras individuais de solo, perfazendo um total de 1000 agregados avaliados. A partir da obtenção de 1000 imagens fotográficas, com auxílio de um programa de processamento de imagens, obtêm-se um banco de dados referentes aos parâmetros morfométricos. Através do uso de tecnologia Fuzzy obteve-se um banco de dados numéricos referente à tipificação com base na análise visual da forma, superfície e biogênese dos agregados. Para cada conjunto de dados foi elaborado uma representação gráfica da variabilidade e seu respectivo quadro analítico descritivo. Com auxílio de medidas separatrizes do tipo quintis os dados foram classificados de acordo com a tipologia de ocorrência. Foram utilizados como parâmetros morfométricos o “diâmetro de Feret”, e como parâmetro de tipificação rugosidade de superfície e a “saída Fuzzy de tipificação” (os valores de integração com uso da tecnologia Fuzzy) o qual denominamos “Indicie Fuzzy de Tipificação”. Os resultados permitem afirmar que o trabalho atendeu os objetivos proposto de oferecer para sociedade uma “metodologia para qualificar a agregação em amostras de solos agrícolas”. Os resultados permitem aceitar as hipóteses formuladas e concluir que o estudo sobre efeitos da variabilidade permite quantificar, diagnosticar e qualificar o estado de agregação de amostras de solo. / Environmental issues involving the soil management effects and degradation are increasing and need to be extensively researched to be managed. New knowledge about solutions has been produced by academic research, but is still insufficient to solve the problems faced by technicians and other people involved to the field land use planning and degradation problems. Furthermore, the management of soil quality and land reclamation is complex, requiring different technologies for diagnosis and evaluation. The use of indicators, such as geometric mean diameter and percentage distribution of aggregate size, represents classical approaches, but both have limitations in treating the complexity of soil aggregation process. The soil aggregation has been studied since the beginning of the last century, but few advances have been made to popularize it to analyze agricultural soil quality. There are several difficulties to develop laboratory routines and practical tool to evaluate it. The use and processing of high resolution images have been widely applied in several fields of science and represents an interesting solution to study soil aggregation. To fill the existing gap, this works presents a methodological proposal to assess the quality of soil aggregation, by a classification of soil aggregates in terms of composition and variability. Agricultural soil aggregates were analyzed by three attributes: shape, surface and biogenesis. These parameters were used as indicators of soil aggregation quality, and the variability on each parameter was evaluates for two samples of medium texture red latosol, one of them referring to a plot of soil that received a fertilizer/aggregate product Microgeo® and another without receiving it. The aggregates were passed through the dry sieving process using five different sizes. The laboratorial analysis was performed by subsampling 100 aggregates from each sieve, totaling 500 aggregates per soil samples, and making a total of 1000 aggregates. Each soil aggregate was photographed, totalling1000 pictures, later processed on ImageJ. All results were organized in a database, containing information about the morphometric parameters of all soil aggregates. Fuzzy Logic was employed to transform the aggregate type into numeric values, using the visual analysis of the shape, surface and biogenesis. For each data set, a graphical representation of the variability and its descriptive statistics were calculated, producing an analytical framework. Statistical measures were used to classify the samples according to occurrence of aggregate type. To classify the samples and two sets of indexes were developed. The first one was based on the "Feret diameter", used as morphometric indicator, and the second one based on the "Fuzzy typing output", index produced by the integration of the values of shape, surface and biogenesis by a Fuzzy Inference System, which we call "Fuzzy index of typing". These results allowed affirming that the work fulfill the proposed objectives, offering to society a "methodology to qualify the aggregation quality in samples of agricultural soils". The results also allowed us to accept the formulated hypotheses and conclude that the study of variability can be used to quantify, diagnose and qualify the state of aggregation of soil samples.
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Reação álcali-agregado : avaliação do comportamento de agregados do sul do Brasil quando se altera o cimento utilizado / Alkali-aggregate reaction: evaluation on the behavior of the aggregates from southern region of Brazil when different types of Portland cements are appliedBonsembiante, Francieli Tiecher January 2006 (has links)
A reação química que ocorre entre os hidróxidos alcalinos presentes nos poros do concreto e alguns minerais constituintes dos agregados tem causado sérios danos às estruturas. Até o presente momento a prevenção é a melhor forma de evitar que a reação se desencadeie, uma vez que as soluções remediativas ainda necessitam de estudos mais aprofundados para serem implementadas. Neste sentido, a utilização de adições pozolânicas no concreto tem se mostrado uma alternativa eficaz, sendo que a forma mais fácil de empregá-las é através do uso de cimentos compostos com adições. Porém, são poucos os estudos encontrados avaliando a capacidade desses cimentos na prevenção da reação. No Brasil, além dessa lacuna de conhecimento, faltam informações sobre a reatividade dos agregados utilizados no concreto. Então, o presente estudo avaliou a reatividade dos agregados mais utilizados para confecção de concreto nos estados do Paraná, Santa Catarina e Rio Grande do Sul frente à utilização de quatro tipos de cimento: CP V-ARI, CP V-ARI RS, CP IV e CP II-Z. Os métodos utilizados para essa avaliação foram a análise petrográfica, o ensaio acelerado das barras de argamassa, a microscopia eletrônica de varredura e a espectometria por dispersão de energia. Os resultados da análise petrográfica mostraram que todos os 40 agregados coletados possuem minerais reativos. As expansões medidas no ensaio acelerado acabaram por confirmar a potencialidade reativa desses minerais, pois todas as amostras moldadas com o CP V-ARI, o CP V-ARI RS e o CP II-Z foram classificadas como reativas ou potencialmente reativas, isto é, somente o CP IV foi eficaz para inibir as expansões deletérias. Por outro lado, as análises microscópicas mostraram que mesmo nos prismas menos expansivos houve a formação do gel sílico-alcalino, porém este ficou incluso nos poros da argamassa. Outra conclusão percebida foi a de que as maiores expansões ocorreram com os agregados de origem ígnea vulcânica, principalmente com os basaltos, que além de serem constituídos por minerais muito finos, apresentam em sua matriz mesóstases silicosas amorfas, também conhecidas como vidro vulcânico. / The chemical reaction that occurs between alkali hydroxides contained in concrete pores and some minerals contained in aggregates has been causing serious hazards to concrete structures. So far, prevention is the best way to avoid the occurrence of this reaction, once the solutions to repair the damage still need deeper researches to be implemented. Therefore, the use of Portland cements containing pozzolanic admixtures to produce has been an effective alternative. But there are few researches on the capability of those prevent reaction to occur. In Brazil, besides the lack of knowledge, there is little information about the reactivity of the aggregates applied in concrete production. So this research aimed to evaluate the reactivity of the most used aggregate to produce concrete in the states of Parana, Santa Catarina, and Rio Grande do Sul by testing four different types of cements as described: CP V-ARI, CP V-ARI RS, CP IV and CP II-Z. The methods applied to carry out this evaluation were the petrography analysis, the accelerated mortar bar test, scanning electron microscopy, and the dispersive energy spectrometry. The results obtained showed that all the forty aggregate samples collected have reactive minerals in their composition. The measured expansions during the accelerated test confirmed the reactive potentiality of these minerals, because all samples obtained from the CP V-ARI, CP V-ARI RS, and CP IV were classified as being reactive or potentially reactive, which means that CP IV was the only one capable of inhibit the hazardous expansion. On the other hand, the microscopic analyses showed, even in the less expansive prisms, that the formation of silica-alkaline gel has occurred, but this gel has remained in the pores of the mortar. Another conclusion of this research was that larger expansions occurred with the aggregates from volcanic igneous origin, especially basalts that, besides contained very fine minerals, presented in its matrix amorphous silica, also known as volcanic glass.
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Développement d'outils et de méthodologies pour l'étude de l'organisation et de la localisation in vivo de micro-organismes dans des structures biologiques complexes / Development of devices and methods for the organization and the localisation of micro-organisms in biological complex structuresBeaufort, Sandra 24 June 2010 (has links)
Ce projet concerne l’analyse de l’organisation de populations microbiennes au sein de structures complexescomme des dépôts ou des biofilms.Si différentes méthodes sont couramment utilisées pour étudier la structure globale ou l’organisation localed’agrégats microbiens, peu d’entre elles, permettent de réaliser simultanément ces deux analyses et nécessitentsouvent des étapes de préparation qui pénalisent un approche in-vivo et en dynamique.La stratégie proposée repose sur la mise en oeuvre de micro-organismes modèles autofluorescents (levures etbactéries) qui peuvent sans aucun traitement être directement observés en microscopie. La similitude ducomportement physiologique de ces micro-organismes avec celui des souches sauvages a été démontrée. Lesconditions d’acquisition des images en microscopie confocale ont été optimisées. Des dispositifs spécifiques ontété conçus pour générer des dépôts ou des biofilms dans des conditions de contraintes physico-mécaniques etbiochimiques maîtrisées afin d’analyser simultanément leurs caractéristiques et les performances du bioprocédé.Ainsi les dépôts ont pu être observés in-vivo et in-situ grâce à une cellule de filtration équipée d’une fenêtred’observation. Le développement d’un biofilm mixte composé de levures et bactéries modèles autofluorescentes,dans un réacteur continu spécifique, a également été analysé par microscopie confocale.Le traitement et les analyses des images acquises au cours des expériences ont été effectués et ont permisd‘étudier la structure globale des agrégats biologiques et l’organisation tridimensionnelle des micro-organismesdans ces structures, en mettant par exemple en évidence une répartition hétérogène de deux populationsmicrobiennes dans des dépôts de filtration ou en comparant la capacité de deux espèces microbiennes à formerdes biofilms en étudiant in-vivo la dynamique de croissance de chacune des espèces.Cette étude a en outre permis de démontrer la pertinence de la méthode proposée, de définir ses limites et sonchamp d’application / The aim of this project deals with the analysis of both the local localization and organization of microbialpopulations in complex structures such as deposits or biofilms. Different methods are currently used to study theglobal structure or the local organization of biological aggregates but only few ones allow a combined approachand require ex-vivo analyses.The proposed strategy uses home-designed model auto-fluorescent microorganisms (yeasts and bacteria) whichcan be observed directly by microscopy without any dying treatment. Same kinetic behaviours between the wildstrains and their recombinant ones were demonstrated. The confocal microscopy conditions were optimised.Specific devices were developed to generate deposits or biofilms under controlled and known hydrodynamic orbiochemical environment conditions to analyse their structure characteristics linked to the bioprocessperformances.Based on the proposed strategy, microbial deposits modifications due to pressure constraints were observed invivo in a specifically designed flow cell equipped with a microscope glass coverslip. A mixed biofilm composedby our auto-fluorescent yeasts and bacteria was carried out in a specific bioreactor allowing the sampling ofbiofilms during their development to be analysed by confocal microscopy. Both studies have shown specificorganisations between yeasts and bacteria mainly depending on their size and on the environment conditions(pressure or dilution rate).These studies of both local and global structure of biological aggregates and 3D-organisation of themicroorganisms within theses structures demonstrated the relevance of the proposed strategy defining the limitsof the method and proposing various perspectives for further characterizations and applications
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Análise de cenários de planejamento de lavra para adequação de uso futuro de área de mineração de agregadosSchmitzhaus, Wagner Cristiano January 2018 (has links)
A produção de agregados para construção civil é o maior segmento mineral Brasileiro, em números de produção, sendo formada principalmente por pequenos e médios empreendimentos, normalmente utilizando técnicas e procedimentos obsoletos e pouco um nenhum planejamento tanto para extração quanto para o fechamento da mina. O fechamento de mina e posterior utilização da área ainda é um grande problema visto que existem muitas áreas mineradas em que o plano de fechamento de mina não foi executado, deixando assim um passivo socioambiental elevado, prejudicando a imagem da mineração. Existem diversos exemplos de sucesso em que antigas cavas foram utilizadas para a implantação de novos empreendimentos, como loteamentos, óperas e hotéis. Com o intuito de mostrar a importância do planejamento para fechamento e posterior utilização de área de mineração, bem como a análise ambiental e impactos da atividade na sociedade e meio ambiente, este trabalho tem o objetivo de desenvolver uma metodologia para auxiliar, principalmente o pequeno e médio produtor de agregados, sobre os impactos que o correto planejamento e manejo da operação têm sobre o retorno no uso futuro da área. Foram desenvolvidos diferentes cenários de usos futuros alternativos de uma área de mineração localizada no Litoral Norte do Rio Grande do Sul, que posteriormente foram comparados entre si em relação à recuperação mineral, impactos socioambientais, e retorno financeiro. Ao final do trabalho foi possível visualizar uma metodologia apropriada para a análise de impactos socioambientais e planejamento para preparação da área para o recebimento de novos empreendimentos. A partir destes métodos de análise dispõe-se de diversos cenários comparativos, podendo assim o empreendedor tomar a decisão mais correta em relação ao seu empreendimento minerário e futuros empreendimentos pós-fechamento. / Aggregate production for civil construction is the largest Brazilian mineral segment, in production numbers, consisting mainly of small and medium-sized enterprises, usually using obsolete techniques and procedures and little or no planning for both extraction and closure of the mine. The closure of mines and subsequent use of the area is still a major problem, there are many mined areas where the mine closure plan has not been implemented, thus leaving a high social and environmental liability, damaging the mining image, but there are several examples of use of deactivated mining sites for the implementation of diverse projects. In order to show the importance of planning for the closure and subsequent use of the mining area, as well as the environmental analysis of impacts of the activity on society and the environment, this work has the objective of developing a methodology to assist, especially small and medium aggregate producer, on the impacts that correct planning and management of the operation has on the future use of the area. Different scenarios of future uses of a mining area located in the Northern Coast of Rio Grande do Sul were developed, which were later compared to each other in relation to mineral recovery, socioenvironmental impacts, and financial return. At the end of the work it was possible to visualize an appropriate methodology for the analysis of socio-environmental impacts and planning to prepare the area to receive new projects. From these methods of analysis we have several comparative scenarios, so that the entrepreneur can make the most correct decision regarding his mining enterprise and future enterprises after the closing.
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Reação álcali-agregado : avaliação do comportamento de agregados do sul do Brasil quando se altera o cimento utilizado / Alkali-aggregate reaction: evaluation on the behavior of the aggregates from southern region of Brazil when different types of Portland cements are appliedBonsembiante, Francieli Tiecher January 2006 (has links)
A reação química que ocorre entre os hidróxidos alcalinos presentes nos poros do concreto e alguns minerais constituintes dos agregados tem causado sérios danos às estruturas. Até o presente momento a prevenção é a melhor forma de evitar que a reação se desencadeie, uma vez que as soluções remediativas ainda necessitam de estudos mais aprofundados para serem implementadas. Neste sentido, a utilização de adições pozolânicas no concreto tem se mostrado uma alternativa eficaz, sendo que a forma mais fácil de empregá-las é através do uso de cimentos compostos com adições. Porém, são poucos os estudos encontrados avaliando a capacidade desses cimentos na prevenção da reação. No Brasil, além dessa lacuna de conhecimento, faltam informações sobre a reatividade dos agregados utilizados no concreto. Então, o presente estudo avaliou a reatividade dos agregados mais utilizados para confecção de concreto nos estados do Paraná, Santa Catarina e Rio Grande do Sul frente à utilização de quatro tipos de cimento: CP V-ARI, CP V-ARI RS, CP IV e CP II-Z. Os métodos utilizados para essa avaliação foram a análise petrográfica, o ensaio acelerado das barras de argamassa, a microscopia eletrônica de varredura e a espectometria por dispersão de energia. Os resultados da análise petrográfica mostraram que todos os 40 agregados coletados possuem minerais reativos. As expansões medidas no ensaio acelerado acabaram por confirmar a potencialidade reativa desses minerais, pois todas as amostras moldadas com o CP V-ARI, o CP V-ARI RS e o CP II-Z foram classificadas como reativas ou potencialmente reativas, isto é, somente o CP IV foi eficaz para inibir as expansões deletérias. Por outro lado, as análises microscópicas mostraram que mesmo nos prismas menos expansivos houve a formação do gel sílico-alcalino, porém este ficou incluso nos poros da argamassa. Outra conclusão percebida foi a de que as maiores expansões ocorreram com os agregados de origem ígnea vulcânica, principalmente com os basaltos, que além de serem constituídos por minerais muito finos, apresentam em sua matriz mesóstases silicosas amorfas, também conhecidas como vidro vulcânico. / The chemical reaction that occurs between alkali hydroxides contained in concrete pores and some minerals contained in aggregates has been causing serious hazards to concrete structures. So far, prevention is the best way to avoid the occurrence of this reaction, once the solutions to repair the damage still need deeper researches to be implemented. Therefore, the use of Portland cements containing pozzolanic admixtures to produce has been an effective alternative. But there are few researches on the capability of those prevent reaction to occur. In Brazil, besides the lack of knowledge, there is little information about the reactivity of the aggregates applied in concrete production. So this research aimed to evaluate the reactivity of the most used aggregate to produce concrete in the states of Parana, Santa Catarina, and Rio Grande do Sul by testing four different types of cements as described: CP V-ARI, CP V-ARI RS, CP IV and CP II-Z. The methods applied to carry out this evaluation were the petrography analysis, the accelerated mortar bar test, scanning electron microscopy, and the dispersive energy spectrometry. The results obtained showed that all the forty aggregate samples collected have reactive minerals in their composition. The measured expansions during the accelerated test confirmed the reactive potentiality of these minerals, because all samples obtained from the CP V-ARI, CP V-ARI RS, and CP IV were classified as being reactive or potentially reactive, which means that CP IV was the only one capable of inhibit the hazardous expansion. On the other hand, the microscopic analyses showed, even in the less expansive prisms, that the formation of silica-alkaline gel has occurred, but this gel has remained in the pores of the mortar. Another conclusion of this research was that larger expansions occurred with the aggregates from volcanic igneous origin, especially basalts that, besides contained very fine minerals, presented in its matrix amorphous silica, also known as volcanic glass.
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Gestão ambiental na mineração: planejamento ambiental aplicado na Pedreira Aratu, município de Salvador (BA)Rossini, Fabiano 28 September 2015 (has links)
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Previous issue date: 2015-09-28 / O presente estudo tem como objetivo geral apresentar e discutir todos os procedimentos legais que são necessários para a regularização mineral e ambiental de empresas de mineração de pequeno/médio porte que extraem agregados para a construção civil - especificamente brita. A pesquisa se propõe a fazer uma abordagem geral da mineração no Brasil e no Estado da Bahia, levando-se em conta principalmente todo o contexto ambiental e legal no qual a atividade de mineração se insere. Para tanto foi feito um estudo de caso de uma pedreira da empresa Aratu Mineração e Construção Ltda (Pedreira Aratu) que extrai e comercializa brita na Região Metropolitana de Salvador (BA). Através deste estudo se procura compreender como é feito o planejamento e o gerenciamento ambiental de uma empresa de mineração de agregados. Procura-se responder se os procedimentos administrativos exigidos pela legislação são eficazes para a mitigação dos impactos ambientais causados pela mineração e/ou são instrumentos eficientes para a gestão ambiental da área impactada. Este trabalho tem sua contribuição na medida em que informa à sociedade de que os recursos minerais são bens finitos ou não renováveis e que somente estarão disponíveis para esta e futuras gerações se forem utilizados de forma racional e com o mínimo de agressão possível ao meio ambiente. O método de trabalho utilizado se deu a partir de toda a fundamentação teórica exigida pela legislação (mineral e ambiental) para a atividade, complementada por estudos e dados de campo coletados in loco, tais como: levantamento e avaliação dos impactos ambientais identificados na área da pedreira; análises laboratoriais de amostras de água; e dados sismográficos. Ao final, com base na interpretação dos resultados obtidos, recomenda-se uma série de procedimentos que se fazem necessários para uma melhor gestão ambiental do empreendimento/atividade como um todo, além de sugerir uma readequação e/ou aprimoramento das ações já em curso na Pedreira Aratu. Entre outros, é enfatizada a importância da implantação de um Sistema de Gestão Ambiental (SGA), plano de emergência ambiental, complementação do programa de gerenciamento de resíduos sólidos, demarcação de novas áreas de estéril/bota-fora, redimensionamento das bancadas, clausura de equipamentos da britagem, perfuração total com água, aprimoramento do treinamento e capacitação técnica dos trabalhadores. / This study has the general objective to present and discuss all legal procedures that are required for mineral and environmental compliance for small / medium-sized mining companies that extract aggregates for the construction industry - specifically gravel. The research aims to make a general approach to mining in Brazil and in the state of Bahia, taking into account especially all environmental and legal context in which the mining activity is inserted. To this end it was made a case study of a company's quarry Aratu Mining and Construction Ltd. (Quarry Aratu) that extracts and sells gravel in the metropolitan area of Salvador (BA). Through this study seeks to understand how is the planning and environmental management of an aggregate mining company. Wanted answer whether the administrative procedures required by the law are effective for mitigation of the environmental impacts of mining and / or are efficient instruments for environmental management of the impacted area. This work has its contribution in that it tells the company that mineral resources are finite and non-renewable assets and that will only be available for this and future generations if used rationally and with minimal aggression possible to the environment. The working method used was given from all the theoretical background required by the legislation (mineral and environmental) for activity, complemented by studies and field data collected on-site, such as survey and assessment of environmental impacts identified in the area of quarry; Laboratory tests Water samples; and seismographic data. At the end, based on the interpretation of results, we recommend a series of procedures that are necessary for better environmental management of the project / activity as a whole, as well as suggest a readjustment and / or improvement of the actions already underway in Quarry Aratu. Among others, it is emphasized the importance of implementing an Environmental Management System (EMS), environmental emergency plan, completion of the solid waste management program, demarcation of new areas of sterile / send-off, resizing the stands, cloistered crushing equipment, full drilling with water, improvement of training and technical training of workers.
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