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Análise ambiental de solos e águas subterrâneas contaminadas com gasolina: estudo de caso no município de Guarulhos - SP. / Environmental analysis of soils and ground water contaminated with gas: study case in the municipality of Guarulhos - SP.Trovão, Renata Silva 08 December 2006 (has links)
A Resolução do Conselho Nacional do Meio Ambiente - CONAMA n° 273 evidenciou o problema do vazamento de combustível em postos de gasolina, há muito detectada por técnicos do órgão ambiental do Estado de São Paulo - a Companhia de Tecnologia de Saneamento Ambiental (Cetesb). Esta resolução resolve, principalmente, que: \"A localização, construção, instalação, modificação, ampliação e operação de postos revendedores, postos de abastecimento, instalações de sistemas retalhistas e postos flutuantes de combustíveis dependerão de prévio licenciamento do órgão ambiental competente...\". A gasolina brasileira possui na sua formulação 20% em média de etanol anidro (teor este que varia de acordo com a política energética momentânea) para aumentar a octanagem e reduzir a emissão de monóxido de carbono na atmosfera. No entanto, esta adição, aumenta sua solubilidade, uma vez que o etanol é solúvel em água e na própria gasolina, aumentando também a mobilidade do contaminante, conseqüentemente dos compostos BTEX (benzeno, tolueno, etilbenzeno, xilenos) e hidrocarbonetos monoaromáticos - altamente nocivos à saúde humana. O município de Guarulhos é uma importante cidade da Região Metropolitana do Estado de São Paulo. Tanto seu pólo industrial - altamente diversificado, quanto a presença do Aeroporto Internacional de São Paulo, com a passagem de cerca de 100 mil pessoas por dia, conferem a cidade grande importância na economia do Estado. A água subterrânea é a única fonte de água potável para consumo de grande parte dos bairros da cidade. No entanto, a cidade apresenta um grande percentual de áreas contaminadas por postos de combustíveis. Considerando a população da cidade é possível perceber que um grande número de pessoas convive diariamente com o problema de áreas passíveis de contaminação por hidrocarbonetos. Tendo em vista a problemática acima exposta, este trabalho visa o levantamento dos dados de contaminação das águas subterrâneas, bem como de solos, pela atividade de postos de gasolina, evidenciando o impacto destas contaminações sobre a população da cidade de Guarulhos. Para tanto, realizou-se estudo na documentação existente nos processos de licenciamento ambiental, bem como de reclamação da população, existentes na Cetesb - Agência Ambiental de Guarulhos, quanto aos aspectos geológicos, hidrogeológicos, técnicos e comunitários quanto à evolução das plumas de contaminação e a discussão das remediações aplicáveis e/ou já aplicadas. Para o desenvolvimento desta pesquisa foram utilizados os laudos de análises, os estudos de passivo ambiental e os demais documentos constantes nos processos de licenciamento, apresentados por estes estabelecimentos à Cetesb, visando à obtenção das licenças a que faz referência a Resolução CONAMA n° 273. As diferenças existentes quanto à condutividade hidráulica e a ocorrência de anisotropia são determinantes quando se trata da direção e velocidade da migração da pluma de contaminação nos diversos tipos de solo. São estas diferenças, alguns dos fatores que, somadas a dispersão e a difusão, condicionam o comportamento dos contaminantes no solo (TRESSOLDI, 2002). É importante comentar que o gerenciamento de uma contaminação envolve a remoção de fase livre de produto, a investigação da contaminação remanescente, a avaliação e gerenciamento de riscos e finalmente as medidas de remediação, no entanto, nenhum dos 5 casos estudados apresentou, até junho de 2006, um projeto de remediação, embora todos já estejam removendo a fase livre de contaminante. Este trabalho elaborou propostas conceituais de remediação, com a utilização de desadsorção térmica em conjunto com atenuação natural, implantação de sistemas de Air Strippers e extração multifásica - MPE. Foram escolhidos dois casos dentre os analisados, pois, até outubro de 2006, ainda não havia sido apresentado nenhum projeto para descontaminação vi destas áreas e, um dos empreendimentos, sequer não havia realizado reforma, o que facilita a remoção do solo para uma melhor remediação. / The Resolution of the Nacional Environment Council - CONAMA n° 237 made obviously the problem concerning fuel leak in gas stations, already detected by technicians of the environmental organ of São Paulo State - Company of Environmental Sanitation Technology (Cetesb). This Resolution establishes that: \"the location, construction, installation, modification, enlargement and operation of gas stations, fuel suppliers, fuel retailers and floating gas stations, will depend on the previous licensing by the competent environmental organ...\". The Brazilian gasoline contains approximately 20% of ethanol anhydrous (the content varies according to the energetic politics) to increase the octane and reduce the emission of carbon monoxide in the atmosphere. Nevertheless, this addition increases its solubility, because the ethanol is soluble in both water and gasoline, increasing the mobility of the contaminant, thus the BTEX compounds (benzene, toluene, ethyl benzene, and xylene) and Monocyclic Aromatic Hydrocarbons - highly toxic to the human health. The municipality of Guarulhos is a very important city of the Metropolitan Region of São Paulo State, due to the diversified industry and the presence of the São Paulo International Airport, where approximately 100 thousand people pass daily. The groundwater is the only source of potable water in many districts of the city. However, there are many contaminated areas by gasoline leaking. So far a great number of people live at areas that are susceptible to the contamination by hydrocarbons compounds. Considering this problem, this research consists in collect data about contaminated groundwater and soil by gas stations operations, verifying the impact of contamination on the population. An investigation of the environment licenses was carried out, as well as the citizens complaints at Cetesb - The environmental Agency in Guarulhos, about geological, hydro geological, technical and community aspects related to the plumes of contamination and their evolution and to discuss the appropriate remedy. To develop this research, the analysis certificate, environmental damage and other documents by the licensing process presented at Cetesb, have been used, to obtain the approval according CONAMA nº 273. The differences about hydraulic conductivity and anisotropy are determinant when talking about direction and speed of the contamination plume migration in different soils. These differences, summed to dispersion and diffusion, condition the behavior of contaminants in the soil (TRESSOLDI, 2002). It is important to know that manage a contamination involves removing the free phase of the product, investigating the contamination left, evaluating and managing the risks and measuring remediation. However, neither one of the five cases presented, until June 2006, a project of treatment, even though all of them are removing the free of contaminants phase. This research elaborated proposals concepts of remediation, using thermal desorption with natural attenuation, implantation of the systems Air Strippers and multiphase extraction - MPE. Two cases were chosen among all the situations analyzed, because until October 2006 no project was presented to de-contaminate those areas, and in one case, no reform was done, what facilitates removing the soil to a better remediation.
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Removal of pentachlorophenol and methyl-parathion by spent mushroom compost of oyster mushroom.January 2001 (has links)
by Law Wing Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 192-206). / Abstracts in English and Chinese. / Acknowledgments --- p.i / Abstract --- p.ii / List of Figures --- p.vi / List of Tables --- p.xii / Abbreviations --- p.xv / Chapter 1. --- Introduction / Chapter 1.1. --- Pesticides --- p.1 / Chapter 1.1.1. --- Types and uses --- p.1 / Chapter 1.1.2. --- Development of pesticides --- p.1 / Chapter 1.1.3. --- The case against pesticides --- p.3 / Chapter 1.2. --- Pentachlorophenol --- p.4 / Chapter 1.2.1. --- Production --- p.4 / Chapter 1.2.2. --- Toxicity --- p.4 / Chapter 1.2.3. --- Persistency --- p.6 / Chapter 1.3. --- Methyl-parathion --- p.9 / Chapter 1.3.1. --- Production --- p.9 / Chapter 1.3.2. --- Toxicity --- p.9 / Chapter 1.3.3. --- Environmental fate --- p.12 / Chapter 1.4. --- Conventional methods dealing with pesticides --- p.12 / Chapter 1.5. --- Bioremediation --- p.15 / Chapter 1.6. --- Spent mushroom compost --- p.17 / Chapter 1.6.1. --- Background --- p.17 / Chapter 1.6.2. --- "Physical, chemical and biological properties of SMC " --- p.19 / Chapter 1.6.3. --- Recycling of agricultural residuals --- p.21 / Chapter 1.6.3.1. --- Definition --- p.21 / Chapter 1.6.3.2. --- Types of recycling --- p.22 / Chapter 1.6.4. --- Potential uses of SMC as bioremediating agent --- p.23 / Chapter 1.6.4.1. --- Use of microorganisms in SMC --- p.23 / Chapter 1.6.4.2. --- Use of ligninolytic enzymes in SMC --- p.24 / Chapter 1.7. --- Ligninolytic enzymes --- p.28 / Chapter 1.7.1. --- Background --- p.28 / Chapter 1.7.2. --- What are white rot fungi? --- p.29 / Chapter 1.7.3. --- Why is lignin so difficult to degrade? --- p.29 / Chapter 1.7.4. --- Three main ligninolytic enzymes --- p.32 / Chapter 1.7.4.1. --- Lignin peroxidases (LiP) --- p.32 / Chapter 1.7.4.2. --- Manganese peroxidase (MnP) --- p.36 / Chapter 1.7.4.3. --- Laccase --- p.37 / Chapter 1.8. --- Why SMC was chosen to be the bioremediating agent in my project? --- p.40 / Chapter 1.9. --- Bioremediation of chlorophenols and PCP --- p.44 / Chapter 1.9.1. --- Bacterial system --- p.44 / Chapter 1.9.2. --- Fungal system --- p.45 / Chapter 1.10. --- Bioremediation of methyl-parathion --- p.49 / Chapter 1.10.1. --- Bacterial system --- p.49 / Chapter 1.10.2. --- Fungal system --- p.51 / Chapter 1.11. --- Proposal and experimental plan of the project --- p.51 / Chapter 1.11.1. --- Study the removal of pesticides in both aquatic and soil system --- p.52 / Chapter 1.11.2. --- Research strategy --- p.52 / Chapter 1.11.3. --- Optimization of pesticide removal --- p.53 / Chapter 1.11.4. --- Identification of breakdown products --- p.54 / Chapter 1.11.5. --- Toxicity assay --- p.54 / Chapter 1.11.6. --- Isotherm plot --- p.55 / Chapter 1.12. --- Objectives of the study --- p.56 / Chapter 2. --- Material and Methods --- p.58 / Chapter 2.1. --- Material --- p.59 / Chapter 2.2. --- Production of Spent Mushroom Compost (SMC) --- p.59 / Chapter 2.3. --- Characterization of SMC --- p.60 / Chapter 2.3.1. --- PH --- p.60 / Chapter 2.3.2. --- Electrical conductivity --- p.60 / Chapter 2.3.3. --- "Carbon, hydrogen, nitrogen and sulphur contents " --- p.60 / Chapter 2.3.4. --- Ash content --- p.61 / Chapter 2.3.5. --- Metal analysis --- p.61 / Chapter 2.3.6. --- Anion content --- p.62 / Chapter 2.3.7. --- Chitin assay --- p.62 / Chapter 2.4. --- Characterization of soil --- p.63 / Chapter 2.4.1. --- Soil texture --- p.63 / Chapter 2.4.2. --- Moisture content --- p.64 / Chapter 2.5. --- Basic studies on the removal capacity of pesticides by SMC --- p.65 / Chapter 2.5.1. --- Preparation of pentachlorophenol and methyl- parathion stock solution --- p.66 / Chapter 2.6. --- Experimental design --- p.65 / Chapter 2.6.1. --- In aquatic system --- p.65 / Chapter 2.6.2. --- In soil system --- p.68 / Chapter 2.7. --- Extraction of pesticides --- p.68 / Chapter 2.7.1. --- In aquatic system --- p.68 / Chapter 2.7.2. --- In soil system --- p.69 / Chapter 2.8. --- Quantification of pesticides --- p.69 / Chapter 2.8.1. --- By high performance liquid chromatography --- p.69 / Chapter 2.8.2. --- By gas chromatography-mass spectrometry --- p.71 / Chapter 2.9. --- Optimization of pesticides degradation by SMC in both aquatic and soil systems --- p.72 / Chapter 2.9.1. --- Effect of initial pesticide concentrations on the removal of pesticides --- p.72 / Chapter 2.9.2. --- Effect of amount of SMC used on the removal of pesticides --- p.73 / Chapter 2.9.3. --- Effect of incubatoin time on the removal of pesticides --- p.73 / Chapter 2.9.4. --- Effect of initial pH on the removal of pesticides --- p.73 / Chapter 2.9.5. --- Effect of incubation of temperature on the removal of pesticides --- p.74 / Chapter 2.10. --- The study of breakdown process of pesticides --- p.74 / Chapter 2.10.1. --- GC/MS --- p.74 / Chapter 2.10.2. --- Ion chmatography --- p.74 / Chapter 2.11. --- Microtox® assay --- p.75 / Chapter 2.12. --- Assessment criteria --- p.75 / Chapter 2.12.1. --- In aquatic system --- p.75 / Chapter 2.12.2. --- In soil system --- p.76 / Chapter 2.13. --- Statistical analysis --- p.77 / Chapter 3. --- Results / Chapter 3.1. --- Characterization of SMC and soil --- p.78 / Chapter 3.2. --- Quantification of pesticides by HPLC and GC/MS --- p.82 / Chapter 3.3. --- Extraction efficiencies of pesticides with hexane --- p.82 / Chapter 3.4. --- Stability of pesticides against time --- p.82 / Chapter 3.5. --- Effect of sterilization of soil in the removal abilities of pesticides…… --- p.88 / Chapter 3.6. --- Optimization of removal of pentachlorophnol --- p.88 / Chapter 3.6.1. --- Effect of incubation time --- p.88 / Chapter 3.6.1.1. --- In aquatic system --- p.88 / Chapter 3.6.1.2. --- In soil system --- p.88 / Chapter 3.6.2. --- Effect of initial PCP concentrations and amout of SMC used --- p.91 / Chapter 3.6.2.1. --- In aquatic system --- p.91 / Chapter 3.6.2.2. --- In soil system --- p.94 / Chapter 3.6.3. --- Effect of pH --- p.97 / Chapter 3.6.3.1. --- In aquatic system --- p.97 / Chapter 3.6.3.2. --- In soil system --- p.97 / Chapter 3.6.4. --- Effect of incubation temperature --- p.97 / Chapter 3.6.4.1. --- In aquatic system --- p.97 / Chapter 3.6.4.2. --- In soil system --- p.101 / Chapter 3.6.5. --- Potential breakdown intermediates and products --- p.101 / Chapter 3.6.5.1. --- In aquatic system --- p.101 / Chapter 3.6.5.2. --- In soil system --- p.104 / Chapter 3.7. --- Microtox® assay of PCP --- p.110 / Chapter 3.7.1. --- In aquatic system --- p.110 / Chapter 3.7.2. --- In soil system --- p.110 / Chapter 3.8. --- Optimization of removal of methyl-parathion --- p.113 / Chapter 3.8.1. --- Effect of incubation time --- p.113 / Chapter 3.8.1.1. --- In aquatic system --- p.113 / Chapter 3.8.1.2. --- In soil system --- p.113 / Chapter 3.8.2. --- Effect of initial concentration and amount of SMC --- p.115 / Chapter 3.8.2.1. --- In aquatic system --- p.115 / Chapter 3.8.2.2. --- In soil system --- p.117 / Chapter 3.8.3. --- Effect of incubation temperature --- p.120 / Chapter 3.8.3.1. --- In aquatic system --- p.120 / Chapter 3.8.3.2. --- In soil system --- p.120 / Chapter 3.8.4. --- Potential breakdown intermediates and products --- p.121 / Chapter 3.8.4.1. --- In aquatic system --- p.121 / Chapter 3.8.4.2. --- In soil system --- p.124 / Chapter 3.9. --- Microtox ® assay of methyl-parathion --- p.133 / Chapter 3.9.1. --- In aquatic system --- p.133 / Chapter 3.9.2. --- In soil system --- p.133 / Chapter 4. --- Discussion / Chapter 4.1. --- Characterization of SMC and soil --- p.137 / Chapter 4.2. --- Stability of pesticides against time in aquatic and soil system --- p.141 / Chapter 4.3. --- Effect of sterilization of soil in the removal abilities of pesticides --- p.142 / Chapter 4.4. --- Optimization of removal of PCP --- p.142 / Chapter 4.4.1. --- Effect of incubation time --- p.142 / Chapter 4.4.1.1. --- In aquatic system --- p.142 / Chapter 4.4.1.2. --- In soil system --- p.143 / Chapter 4.4.2. --- Effect of initial PCP concentrations and amount of SMC --- p.144 / Chapter 4.4.2.1. --- In aquatic system --- p.144 / Chapter 4.4.2.2. --- In soil system --- p.147 / Chapter 4.4.3. --- Effect of pH --- p.149 / Chapter 4.4.3.1. --- In aquatic system --- p.149 / Chapter 4.4.3.2. --- In soil system --- p.150 / Chapter 4.4.4. --- Effect of incubation temperature --- p.150 / Chapter 4.4.4.1. --- In aquatic system --- p.150 / Chapter 4.4.4.2. --- In soil system --- p.152 / Chapter 4.4.5. --- Potential breakdown intermediates and products --- p.152 / Chapter 4.4.5.1. --- In aquatic system --- p.152 / Chapter 4.4.5.2. --- In soil system --- p.158 / Chapter 4.5. --- Microtox® assay of PCP --- p.159 / Chapter 4.5.1. --- In aquatic system --- p.159 / Chapter 4.5.2. --- In soil system --- p.160 / Chapter 4.6. --- Removal of PCP by the aqueous extract of SMC --- p.162 / Chapter 4.7. --- Optimization of removal of methyl-parathion --- p.164 / Chapter 4.7.1. --- Effect of incubation time --- p.164 / Chapter 4.7.1.1. --- In aquatic system --- p.164 / Chapter 4.7.1.2. --- In soil system --- p.165 / Chapter 4.7.2. --- Effect of initial methyl-paration concentrations and amount of SMC used --- p.165 / Chapter 4.7.2.1. --- In aquatic system --- p.165 / Chapter 4.7.2.2. --- I in soil system --- p.166 / Chapter 4.7.3. --- Effect of incubation temperature --- p.168 / Chapter 4.7.3.1. --- In aquatic system --- p.168 / Chapter 4.7.3.2. --- In soil system --- p.169 / Chapter 4.7.4. --- Potential breakdown intermediates and products --- p.169 / Chapter 4.7.4.1. --- In aquatic system --- p.169 / Chapter 4.7.4.2. --- In soil system --- p.170 / Chapter 4.8. --- Microtox® assay of Methyl-parathion --- p.173 / Chapter 4.8.1. --- In aquatic system --- p.173 / Chapter 4.8.2. --- In soil system --- p.174 / Chapter 4.9. --- Removal of methyl-parathion by the aqueous extract of SMC --- p.174 / Chapter 4.10. --- The ability of different types of SMC in the removal of organic pollutants --- p.176 / Chapter 4.11. --- The storage of SMC --- p.178 / Chapter 4.12. --- The effect of scale in the removal of pesticides --- p.180 / Chapter 4.13. --- Cost-effectiveness of using SMC as crude enzymes sources --- p.180 / Chapter 4.14. --- The effect of surfactant on the removal of PCP --- p.182 / Chapter 4.15. --- Prospects for employment SMC in removal of pollutants --- p.185 / Chapter 5. --- Conclusions --- p.186 / Chapter 6. --- Future investigation --- p.190 / Chapter 7. --- References --- p.192
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Devires machinima na cultura do softwareLorena Filho, Gilson Moraes 28 April 2010 (has links)
Made available in DSpace on 2015-03-05T18:25:55Z (GMT). No. of bitstreams: 0
Previous issue date: 28 / Nenhuma / Este trabalho apresenta uma investigação sobre o machinima. O termo (derivado da união das palavras machine, animation e cinema) é utilizado tanto para designar a prática da qual resultam, jogando, produtos audiovisuais, quanto para designar os próprios produtos, finalizados. O objetivo do trabalho é situar esta forma de expressão no universo cultural onde ele se encontra, aqui denominado de cultura do software e compreender a maneira com que seus rastros circulam entre os audiovisuais, principalmente em ambientes como a internet. / The following work presents an investigation about machinima. The term (from the words machine, animation and cinema) is used to define the practice on which results, through gameplay, the making of audiovisual products, and to define the resulting videos. This work objective is to situate this form of expression in the cultural universe where they are found, denominated here as software culture and to comprehend the way in which its trails circualte around the audiovisual products, mainly in enviorments such as the internet.
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Avaliação do processo de transporte e remediação com nano ferro de valência zero em um solo residual contaminado com cromo hexavalente / Evaluation of transport process and remediation with nano zero valent iron in a residual contaminated soil with hexavalent chromiunReginatto, Cleomar January 2017 (has links)
O homem cada vez mais interfere e contamina o meio ambiente. Acidentes envolvendo o derramamento de substâncias químicas no solo tem sido cada vez mais frequente, gerando preocupação aos órgãos ambientais, visto que essa contaminação promove riscos à saúde humana, o que torna necessário intervenções que impulsionam o aprimoramento de técnicas de remediação. Dentre essas técnicas, a utilização de nanopartículas, em especial as nanopartículas de ferro de valência zero, têm se destacado para uso em remediação devido ao baixo custo de produção, elevada reatividade para contaminantes orgânicos e inorgânicos e baixa toxicidade. Para contaminantes inorgânicos não se tem definidas as melhores relações de nano ferro em relação ao contaminante e também o comportamento no solo. Dessa forma o objetivo do trabalho foi avaliar o transporte e a aplicação de nanopartículas de ferro para remediação de um solo residual argiloso, contaminado com cromo hexavalente. O trabalho foi dividido em três fases, em que na primeira foi avaliado a melhor concentração, tipo de nano ferro e determinação do parâmetro de filtração através do uso do ensaio em coluna de parede flexível com corpos de prova indeformados. Na segunda fase, a partir dos resultados da primeira, foram realizados ensaios de remediação do solo contaminado em bancada para se definir as melhores relações entre o nano ferro e o contaminante. E na terceira fase foram realizados ensaios com corpos de prova deformados e contaminados (800mg/Kg de Cr(VI)), para se avaliar a influência da pressão de injeção na eficiência do processo de redução do Cr (VI) Para realização dos ensaios de coluna, foi utilizado um solo residual argiloso, moldando-se corpos de prova de 5 cm de diâmetro e 5 cm de altura, utilizados na fase 1 e 3. Para avaliação do transporte e determinação do parâmetro de mobilidade de filtração foram utilizados 3 tipos de nanopartículas de ferro com e sem estabilizantes, nas concentrações de (1g/L, 4g/L, 7g/L e 10g/L), avaliando mudança na condutividade hidráulica do solo e concentração retida no meio. O parâmetro de filtração foi determinado utilizando-se o modelo analítico proposto por Reddy et al., (2014). Os resultados demonstram que as nanopartículas apresentam uma alta reatividade, porém baixa mobilidade para concentrações mais elevadas, tendo influência também o uso de estabilizantes. Os melhores valores obtidos nesta fase foram para concentrações de 1g/L e 4g/L, tanto para a mobilidade, quanto para a mudança na condutividade do meio O parâmetro de filtração, variou de 10-3s-1, para o nano ferro com surfactante e 10-2s-1, para o nano ferro sem surfactante. Para a remediação do cromo hexavalente se observou uma eficiência de 87% para a relação de 1000mg de Fe° para 23 mg de Cr(VI). Utilizando 4g/L na referida relação agente redutor e contaminante, em coluna se observou que maiores valores de pressão aumentam a eficiência da redução, porém acabam favorecendo a colmatação dos vazios do solo pelas nanopartículas. Utilizando uma pressão de 100Kpa, se obteve um valor de redução máximo próximo de 50%, muito menor que aqueles em bancada. Assim o uso de nanopartículas de ferro é eficiente para remediação de um solo argiloso contaminado com cromo (VI) ex situ, pois o contato do contaminante com o agente redutor se torna mais fácil pela melhor homogeneização do solo. As nanopartículas com surfactante apresentam melhor movimentação no solo e menor valor de filtração, sendo indicado o uso de uma concentração de até 4 g/L para não alterar as características naturais do meio. / The human being is constantly interfering and contaminating the environment. Accidents evolving the spill of chemical and toxic substances in the soil has been more frequently nowadays. This topic became a concern to the environmental regulation departments around the world, since this contaminations promote risks to the human health. In this way the necessity for improvements in the remediation techniques is required. Among the techniques, the use of nanoparticles zero valent iron has being highlight for use in remediation process due it's low cost for production, low toxicity and high reactivity for organic and inorganic contaminants. For inorganic contaminants the best nanoiron/contaminant ration and also the behavior in the soil have not been defined. Thus, the objective of this work was to evaluate the transport and the application of iron nanoparticles for the remediation of residual clay soil contaminated with hexavalent chromium The work is divided in three phases: The first evaluated the best concentration, type of nanoiron and determination of the filtration parameter through the use of the flexible wall column test with undeformed specimens. In the second phase, from the results of the first phase remediation tests were carried out on the contaminated soil in the workbench to define the best relations between the nanoiron and the contaminant. In the third phase, tests with deformed and contaminated test specimens (800 mg / kg Cr (VI)) were carried out to evaluate the influence of the injection pressure on the Cr (VI) reduction efficiency. To perform the column tests, a residual clay soil was used, molding test pieces 5 cm in diameter and 5 cm in height, used in phase 1 and 3. For evaluation of the transport and determination of the parameter of mobility of filtration (1 g / L, 4 g / L, 7 g / L and 10 g / L) were used, evaluating changes in soil hydraulic conductivity and the concentration retained in the system. The filtration parameter was determined using the analytical model proposed by Reddy et al., (2014).The results demonstrate that the nanoparticles have a high reactivity, but low mobility at higher concentrations, and also the use of stabilizers. The best values obtained in this phase were for concentrations of 1g/L and 4 g/L, both for mobility and for the change in conductivity of the system The filtration parameter ranged from 10-3s-1, for the nanoiron with surfactant and 10-2s-1, to the nanoiron without surfactant. For the remediation of the hexavalent chromium, an efficiency of 87% was observed for the ratio of 1000mg Fe ° to 23mg Cr (VI). By using 4g / L in the referred reducing agent and contaminant ratio, it was observed in column that higher pressure values increase the reduction efficiency, but they end up favoring the filling of the voids of the soil by the nanoparticles. Using a pressure of 100Kpa, a maximum reduction value of around 50% was obtained, much lower than those in bench. Thus, the use of iron nanoparticles is efficient for the remediation of a clay soil contaminated with chromium (VI) in deformed samples, since the contact of the contaminant with the reducing agent is made easier by better homogenization of the soil. The nanoparticles with surfactant present better a better movement in the soil and a lower filtration value, being indicated the use of a concentration of up to 4 g/l in order not to alter the natural characteristics of the system.
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Remediation and intertextuality in Garner's 'politically correct' representation of CinderellaSnayer, Leylanie January 2017 (has links)
Magister Artium - MA (Linguistics, Language and Communication) / Fairy tales have been changing continuously. From the likes of the Greek and Chinese
versions of the Cinderella tale, Cinderella has been transformed into other versions.
Charles Perrault and The Brothers Grimm had their way with the story of Cinderella with
both parties putting their own mark on the tale. Disney made the story notorious as the
consumers mostly tend to remember Disney's version and not earlier writers of the story
(Zipes, 1999). Since then, various other versions in the current sphere of story-telling,
especially through movie-making, have had a series of re-telling of the story. James
Finn Garner's "Politically Correct Bedtime Stories" has made its mark in the world of
politically correct, versions of fairy tales. He has graced readers with his satire and
thereby challenged the more traditional versions of the story of Cinderella (and others)
by posing a dry, humorous twist and facing the 'issues' which underlie the social
problems in Cinderella such as equality, sexism and patriarchal, inappropriate gender
biased terminology. Garner takes it upon himself to remediate the story of Cinderella
through transformations of events and socially structured power relations, reworking the
plot and characters and reformulation of gender-biased terminology. This results in a
witty politically correct remodelling of the story which upholds a general moral in line
with the contemporary socio-political ethos, championing usage of politically correct
language.
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Remediação do composto tetracloroeteno em subsuperfície através do processo de oxidação química in situ (ISCO) / Remediation of the compound tetrachloroethene in the subsurface through the in situ chemical oxidation process (ISCO)Sciulli, Berguedof Elliot 22 August 2008 (has links)
Este trabalho apresenta os resultados obtidos no processo de remediação de uma área impactada pelo composto tetracloroeteno através do emprego da tecnologia de oxidação química in situ (ISCO). O teste de bancada realizado em uma amostra de água subterrânea da área de estudo tratada com uma solução de 5% de permanganato de potássio resultou em um percentual de remoção da massa de tetracloroeteno e seus produtos de degradação natural (tricloroeteno, dicloroeteno e cloreto de vinila) superior a 99%. Ao todo, foram injetados em subsuperfície 2950 kg de permanganato de potássio a uma concentração de 6% para o tratamento de 20000 m³ de um aqüífero impactado pelo composto tetracloroeteno e os seus produtos de degradação natural. A injeção de permanganato potássio resultou na destruição de aproximadamente 70% das concentrações de tetracloroeteno e seus produtos de degradação natural na área alvo de remediação dentro de um período de 30 dias após o término da aplicação do oxidante em subsuperfície, comprovando a eficiência do processo de oxidação química in situ para o tratamento de águas subterrâneas impactadas pelo composto tetracloroeteno. / This work presents the results obtained during the remediation process of an area impacted by the compound tetrachloroethene applying the technology of in situ chemical oxidation (ISCO). The bench test performed in a groundwater sample from the study area treated with a 5% potassium permanganate solution resulted in a percentage removal of tetrachloroethene mass and its natural degradation products (trichloroethene, dichloroethene and vinyl chloride) superior than 99%. In total, it was injected in the subsurface 2950 kg of potassium permanganate with a concentration of 6% in order to treat 20000 m³ of an aquifer impacted by the compound tetrachloroethene and its natural degradation products. The potassium permanganate injection resulted in the destruction of approximately 70% of the tetrachloroethene concentration and its natural degradation products in the target area within a period of 30 days after finishing the oxidant application in the subsurface, confirming the efficiency of the in situ chemical oxidation process for treating groundwater impacted by tetrachloroethene.
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Towards A Better Understanding of Contaminant Fate in Plastic Plumbing Systems and Their RemediationXiangning Huang (5929781) 17 January 2019 (has links)
<p><a>This dissertation focused on better understanding the
fundamental processes that control organic and inorganic contaminant
interaction with plastic plumbing pipes. Plastic pipes are increasingly being
installed for drinking water plumbing, but their role in affecting drinking
water quality has received little study. It is well-known that plastic pipes
can sorb and release organic contaminants and be difficult to decontaminate.
Several problems were identified in the literature and through discussions with
industry: (1) Past guidance issued to communities affected by petroleum
contaminated water does not seem to specifically consider plastic plumbing pipe
remediation, (2) investigators have also identified heavy metals can accumulate
on pipe inner walls, (3) Others have proposed certain heavy metals can catalyze
plastic water pipe degradation, (4) No nondestructive cleaning methods were found
for removing metal scales from plastic pipes.</a> These topics were a basis for
studies conducted because lack of information inhibits greater protection of
public health, safety, and welfare.</p>
This dissertation involved the application of
knowledge and techniques from the environmental engineering and science,
polymer engineering, and material science disciplines. Chapter 1 focused on the
response of copper and plastic pipes (i.e., chlorinated polyvinylchloride (cPVC),
high-density polyethylene (HDPE), crosslinked polyethylene (PEX)) exposed to
petroleum contaminated drinking water. Bench-scale results revealed that pipe
rinsing followed by a single 3 day water stagnation period removed target
monoaromatic hydrocarbons (MAH) from copper pipes, but much longer (<u>></u>15
days) time was required for decontaminating cPVC, HDPC, and PEX pipes. Benzene,
trimethylbenzene and polynuclear aromatic hydrocarbons, some of which are not
typically considered in drinking water contamination investigations, were found
desorbed into clean drinking water from pipes. Future plumbing decontamination
guidance should consider the conditions necessary for plastic pipe remediation.
Chapter 2 describes the influence of drinking water conditions on heavy metal
contaminant – low density polyethylene (LDPE) pellet surface interactions.
Mixed metal drinking water solutions were applied and contained Cu, Fe, Mn, Pb
and Zn at 30 µg/L. LDPE was selected as the model polymer because of its prior
use for piping in Europe, use in bench-scale studies by others, and similarity
to products used for the manufacture of more complex materials in the USA
(HDPE, PEX). As expected, metal loadings were about 5 times greater for aged
LDPE pellets suspended in solution compared to new LDPE pellets. This difference
was attributed to the aged plastic surfaces having oxygen containing functional
groups, increased surface area, and enhanced hydrophilicity. Metal loading was
lower at pH >9.5 and in the presence of dissolved organic contaminants. The
presence of free chlorine and corrosion inhibitor also decreased metal
adsorption onto LDPE pellets. These factors likely enabled metal precipitation
thereby not allowing metal species to adsorb to LDPE pellets suspended in
water. XPS results showed deposited metals (i.e., Cu, Pb, Zn) primarily
consisted of hydroxides and oxides. To further understand heavy metal – plastic
pipe interactions, Chapter 3 involved the use of metal and plastic pipe rigs
and exhumed PEX plumbing pipes. Exhumed cold and hot water PEX pipes contained
a noticeable amount of heavy metals (i.e., most abundant metals were 2049 mg/m<sup>2</sup>
Fe, 400 mg/m<sup>2</sup> Ca, 438 mg/m<sup>2</sup> Zn and 150 mg/m<sup>2</sup> P). Metal
release and deposition onto PEX pipe was examined using bench-scale pipe rigs
that contained new PEX pipe, brass valves, and copper pipe. Two water matrices
(pH 4 and 7.5) and two temperatures (23<sup>o</sup>C and 55<sup>o</sup>C) were
explored. The pH 4 water often accelerated metal leaching from brass valves,
and a greater amount of heavy metals deposited on PEX pipes at high water pH
and temperature (pH 4 and 55<sup>o</sup>C) conditions. Oxygen containing
functional groups were detected on PEX pipes connected to a brass valve or a
brass valve combined copper pipe, but were not found on PEX pipe only
(controls) samples, indicating that certain configurations may facilitate
plastic pipe degradation. The last chapter describes the ability of a new
lignin derived ligand to remove metal deposits from exhumed PEX plumbing pipes.
When the ligand concentration was ≥ 5mM, more than 95% of sorbed metals (i.e.,
Cu, Fe, Mn, Pb and Zn) were removed. The ligand favored certain metals over
others (Cu > Zn > Fe > Mn > Pb) and heavy metal removal mechanisms
were proposed. This dissertation provides insights into the role of plastic
pipes on drinking water quality. As plastic pipes continue to be installed, it
is in the interest of public health, welfare, and safety to understand their
role in positively and negatively affecting drinking water safety.
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Toxicities of DDE and cadmium towards the wheat triticum aestivum and their cleanup by the fungus pleurotus pulmonarius. / CUHK electronic theses & dissertations collectionJanuary 2004 (has links)
Gong Jun. / "March 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 254-294) / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
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Properties, functionality and potential applications of novel modified iron nanoparticles for the treatment of 2,4,6-trichlorophenolUnderwood, Laura Ann January 2018 (has links)
2,4,6-trichlorophenol (TCP) is a pervasive carcinogenic water contaminant found in a wide variety of water and waste systems and is a pertinent model compound of broader aromatic organics, specifically organo-halide pesticides. These compounds are persistent in the environment and show resilience to regular water and waste treatment protocols thus warranting the development and implementation of novel treatment materials for improved contaminant removal. Zero-valent iron (ZVI) has demonstrated the ability to remove or degrade a wide variety of inorganic and organic water contaminants, including chlorophenols, and has been widely applied for in-situ groundwater remediation where contamination is often localised in a low-oxygen environment. ZVI's broader applications in water treatment have remained mainly limited due to corrosion, particle dispersion, and confinement issues in deployment. This work, therefore, explored the development, functionality, and potential application of new modified nZVI materials (nZVI-Osorb) and assessed their potential to improve iron's intrinsic functionality while also gauging the material's viability for TCP remediation in water and waste systems. Materials produced in this thesis were prepared utilising three different embedment procedures (1-pot, multiple additions, oxygen-free). All embedment methods resulted in tightly bound composites featuring high surface areas (340.2-449.1 sq. m/g) with net iron composition ranging from 10% to 29.78% by mass. Electron imaging microscopy verified even dispersion of iron throughout the substrate. Composite materials did not exhibit a delayed rate of atmospheric corrosion over nZVI controls evincing an 18% nZVI0 loss per day until reaching a stabilised concentration (7%) after 48 hrs. nZVI-Osorb composites did produce more favourable iron oxide species which remain conducive to electron transfer from core Fe0 atom. After 50 days, a majority of nZVI in nZVI-Osorb had oxidised to maghemite (30%) and magnetite (26%) compared to control nZVI producing 19% and 12% respectively. Unreactive hematite accounted for 47% of the control and just 36% of the composite. While 1-pot embedment allowed the most substantial control over final iron composition, the oxygen-free method allowed the most reliable preservation of initial nZVI0 concentrations through restricted oxidation. Materials generated through oxygen-free embedment were utilised in the following water treatment trials with TCP. Parameters related to sorption and degradation mechanisms of TCP by nZVI-Osorb were tested in aerobic conditions, e.g. surface and potable water. nZVI-Osorb materials demonstrated high extraction capacity for TCP from aqueous solutions (Qe=1286.4 ± 13.5 mg TCP/g Osorb, Qe=1253 ± 106.7 mg TCP/g nZVI-Osorb, pH 5.1, 120mg/L TCP) and followed pseudo second order kinetics. In the broader class of chlorophenols, sorptive affinity mirrored partitioning values with highly substituted chlorophenols displaying the highest sorption capacities. Degradation of TCP by nZVI-Osorb or nZVI controls was not observed due to corrosive hindrance and inadequate reductive capacity, suggesting that materials may not be suitable for highly aerated surface and potable water treatment systems. Environmental conditions pertinent to sorption and degradation mechanisms were evaluated to improve understanding and robustness of functionality in low-oxygen applications, such as wastewater and anaerobic digesters, where nZVI-Osorb treatment is anticipated to be advantageous to TCP sorption and methane production. pH was found to influence sorption dramatically. Acidic solutions below 5 found sorption > 90%. This capacity was reduced to < 30% when pH was raised above TCP pKa value (6.23) to 7 and above. Further trials found a positive effect on TCP sorption (+7.55%) linked to net pH reduction (5.1 to 3.3) with the addition of secondary acids (volatile fatty acids: acetic, propionic, butyric, 3x 100mg/L) commonly found in anaerobic digester systems. Salinity did not affect TCP sorption. The removal of dissolved and atmospheric oxygen increased total sorption (40ppm-+1.94%, 100ppm- +7.93%, 200ppm- +0.89%, 400mg/L- +14.59%) through reduced iron corrosion and the production of favorable iron oxides, but did not facilitate contaminant degradation. Biodegradation mechanisms for TCP have broadly been established, and new research has supported the improved cometabolic degradation of recalcitrant contaminants like TCP and PCP in nZVI-dosed anaerobic digesters. Model anaerobic digester systems (3.9 g/L nZVI-Osorb, 25mg/L TCP, 240 mg/L acetic, 120mg/L propionic, 120mg/L butyric acid) containing bioreactor sludge (62.5%) were observed through standard water quality diagnostics (pH, ORP, COD, head pressure) for 14 days and suggested that nZVI-Osorb did not inhibit cellular processes. Increased electron activity from iron corrosion and hydrogen gas production, increased overall pH and decreased total ORP in these AD systems. TCP degradation by-products (DCP, CP) were detected in dilute concentrations (< 0.01 mg/L) with poor recovery by LC-MS/MS. Results suggest that nZVIOsorb may be well-suited additive for AD systems. This study contributes to knowledge of the properties, functionality, and treatment mechanisms of metal-sorbent composites with a model chlorinated aromatic water contaminant in aerobic and anaerobic environments. The work identifies favourable environmental and process conditions to apply these materials in larger scale applications, particularly, anaerobic digestion and provides support for the continued refinement and improvement of nZVI based remediation systems.
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Élaboration d’un programme de remédiation cognitive au profit des patients bipolaires : approche clinique et neuropsychologique / Designing an ecological cognitive remediation intervention for bipolar disorders : a clinical and neuropsychological approachIsaac, Clemence 08 June 2018 (has links)
Introduction : Près de 60% des patients bipolaires stabilisés souffrent de déficits cognitifs associés à des troubles du fonctionnement psychosocial. En l’absence de traitement, ces troubles sont susceptibles de persister tout au long de la vie. Malgré cela, les déficits cognitifs ont longtemps été ignorés dans les troubles bipolaires et il n’existe que peu d’études à l’heure actuelle ciblant cette problématique. Méthodologie : Nous avons développé le programme individuel écologique de remédiation cognitive ECo, élaboré pour les troubles de l’humeur. Nous avons mené une série d’études empiriques afin d’explorer les corrélats psychologiques des troubles cognitifs, ainsi que l’amélioration cognitive, fonctionnelle et psychologique de patients bipolaires suite à une intervention en remédiation cognitive ou une psychothérapie individuelle.Résultats : Les troubles métacognitifs pourraient être associés à une augmentation de la fréquence des activités des patients et à une fragilisation sur le plan cognitif et émotionnel. La remédiation cognitive, et en particulier le programme ECo, a permis d’améliorer les capacités de résolution de problèmes dans notre population. Le programme ECo peut normaliser les fonctions cognitives déficitaires et la régulation métacognitive chez certains patients, mais peut également améliorer la résistance aux facteurs de stress, le contrôle émotionnel, l’ouverture aux relations et l’estime de soi.Conclusion : Un programme de remédiation cognitive écologique et individualisé, centré sur la métacognition et le sentiment d’efficacité personnelle, peut contribuer à améliorer des composantes de la santé fonctionnelle chez les patients bipolaires. / Background: Nearly sixty percent of stabilized bipolar patients suffer from important cognitive impairments that lead to significant functional disabilities. Without proper treatment, these impairments remain throughout lifespan. However, cognitive deficits in bipolar disorders have been overlooked and only a few studies investigated treatments to improve cognitive functioning for bipolar patients. Method: We developed ECo, an individual ecological cognitive remediation intervention that was designed for mood disorders. We conducted experimental studies to investigate psychological correlates of cognitive impairments, and the cognitive, functional and psychological improvements of bipolar patients after either cognitive remediation or individual psychotherapy.Results: Our results suggest that metacognitive impairments lead to an increased frequency of everyday life activities that can create a cognitive and emotional overload. We observed that cognitive remediation, and in particular the ECo program, can improve problem solving skills in our population. The ECo program can improve impaired cognitive functions and metacognitive regulation, as well as coping skills, emotional control, openness to relationships and self-esteem.Conclusion: An ecological, individualized cognitive remediation program, targeting metacognition and self-efficacy, can contribute to an improvement of functional health components in bipolar disorders.
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