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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Restos sob(re) restos: perspectivas psicanalíticas acerca da poluição e degradação de ambientes no capitalismo de consumo / Rest under/upon rest: psychoanalytic perspectives about the pollution and degradation of environments in consumer capitalism

Costa, Luanda Francine Garcia da 03 August 2018 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2018-09-28T12:26:12Z No. of bitstreams: 1 Luanda Francine Garcia Da Costa.pdf: 1803240 bytes, checksum: 16e83d1434313cbd9f12b25f939af988 (MD5) / Made available in DSpace on 2018-09-28T12:26:12Z (GMT). No. of bitstreams: 1 Luanda Francine Garcia Da Costa.pdf: 1803240 bytes, checksum: 16e83d1434313cbd9f12b25f939af988 (MD5) Previous issue date: 2017-08-03 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Through the perturbing phenomenon of the extension of garbage, which in the contemporaneity reaches planetary proportions, the present research proposes to bring up some discussions from the perspective of Freudian and Lacanian psychoanalysis, concerning the implication of the subject of the unconscious in the act of polluting the natural environments in society of consumer capitalism. Basing us on the psychoanalytic theory research in articulation with other knowledge areas, especially with philosophy and sociology, we intend to establish conjectures between the transitional context of the psychic structure of the neurotic subject – in what concerns their entry into language and the production of the rest Real – and in the actual historical context, researching the theme of the degradation of the environments through pollution in the horizon of the political and economical system of consumer capitalism in their specificity of rest production and the rejection of the rest Real. In the course of the research connective openings and possibilities were presented between the scopes which treat the rest as pollution, the rest as operation of constitutive loss of the subject and of the rest as indescribable opacity related to the body, as well their management through capitalist discourse in order to think the place of rest production in the contemporaneity, where we conclude that there is, beyond the phenomenon, the place of a symptom / Mediante o perturbador fenômeno de extensão do lixo que atinge proporções planetárias na contemporaneidade, a presente pesquisa se propõe a levantar algumas discussões sob a perspectiva da psicanálise freudiana e lacaniana acerca da implicação do sujeito do inconsciente no ato de poluir os ambientes naturais na sociedade capitalista de consumo. Pautando-nos na pesquisa teórica psicanalítica em articulação com outras áreas do conhecimento, em especial, a filosofia e a sociologia, tencionamos estabelecer conjecturas entre o contexto transhistórico da estrutura psíquica do sujeito neurótico – no que concerne à sua entrada na linguagem e à produção do resto Real – e o contexto histórico atual, investigando o tema da degradação dos ambientes pela poluição, no horizonte do sistema político-econômico capitalista de consumo, em sua especificidade de produção de restos e recusa do resto Real. Ao longo da pesquisa, foram apresentadas aberturas e possibilidades conectivas entre os âmbitos que tratam do resto como poluição, do resto como operação de perda constitutiva do sujeito e do resto como opacidade indescritível remetida ao corpo, bem como o gerenciamento desses pelo discurso capitalista, a fim de pensarmos o lugar da produção dos restos na contemporaneidade – o que concluímos ser, para além de um fenômeno, o lugar de um sintoma
22

Investigação de contaminantes mutagênicos de matrizes ambientais em área de risco ecotoxicológico

Lemos, Andréia Torres de January 2011 (has links)
A crescente introdução de variados poluentes em matrizes ambientais de áreas urbanas causa prejuízos ao ecossistema e dificulta as medidas de controle ambiental. Essas substâncias, após liberadas, se distribuem e interagem de acordo com suas características e as do meio receptor. Indicadores precoces de contaminação permitem a adoção de medidas preventivas aos danos causados pela poluição ambiental. O presente estudo teve por objetivo investigar a ação de substâncias genotóxicas em diferentes frações de material particulado atmosférico e solos, analisando a presença de contaminantes orgânicos e inorgânicos. Para este fim, foi empregado o ensaio Salmonella/microssoma em amostras de áreas urbanas caracterizadas como urbano-residencial e urbano-industrial, na cidade de Rio Grande, RS. Amostras de material particulado atmosférico (PTS e PM2,5) e de solo superficial (composição granulométrica total e fração <0,5mm) foram preparadas por diferentes métodos de extração. Este estudo apresenta uma primeira caracterização de PM2,5, através do ensaio Salmonella/microssoma, no Brasil. O estudo de extratos orgânicos e aquosos de PTS e PM2,5 evidenciou a presença de compostos metálicos na fração aquosa, potencialmente biodisponíveis, bem como maior risco de exposição associado à fração de compostos orgânicos das partículas finas. A mutagênese foi detectada, mesmo em amostras de particulados que se encontravam em conformidade com os parâmetros de qualidade recomendados. A análise das extrações ácidas dos solos mostrou que as chuvas da região podem atuar como rota de contaminação ambiental, com risco adicional na disponibilização de substâncias tóxicas nos eventos de precipitação ácida. O estudo mostrou que o emprego do solo com mínima alteração é mais apropriado para os ensaios de mutagênese. A utilização conjunta de diferentes métodos de extração de compostos orgânicos e inorgânicos permite uma avaliação integradora da qualidade de matrizes ambientais complexas, favorecendo a adoção de medidas preventivas para a proteção do ecossistema. / The increasing introduction of different pollutants into the environmental matrices of urban areas damages the ecosystem and makes it difficult to perform environmental control. After these substances are released, they are distributed and interact according to their own characteristics and those of the receiving environment. Early indicators of contamination allow measures to be adopted to prevent damage caused by environmental pollution. The purpose of this study was to investigate the action of genotoxic substances in different fractions of atmospheric particulate matter and soils, analyzing the presence of organic and inorganic contaminants. For this, the Salmonella/microsome assay was used on samples of urban areas characterized as urban-residential and urban-industrial, in the city of Rio Grande, RS. Samples of atmospheric particulate matter (TSP and PM2.5) and of surface soil (total grain size composition and fraction <0.5mm) were prepared using different extraction methods. This study presents a first characterization of PM2.5 in Brazil, through the Salmonella/microsome assay. The study of organic and aqueous extracts of TSP and PM2.5 showed the presence of potentially bioavailable metallic compounds in the aqueous fraction, as well as a greater risk of exposure associated with the fraction of organic compounds of the fine particles. Mutagenesis was detected even in samples of particulates that were in accordance the recommended quality parameters. Analysis of acid extractions from the soils showed that rainfall in the region may act as an environmental contamination route, with an additional risk of making toxic substances available in acid precipitation events. The study showed that the use of minimally altered soil is more appropriate for mutagenesis assays. The joint use of different methods for organic and inorganic compound extractions allows an integrated evaluation of the quality of complex environmental matrices, favoring the adoption of preventive measures to protect the ecosystem.
23

An Investigation of Urban Mobile Source Aerosol Using Optical Properties Measured by CRDT/N: Diesel Particulate Matter and the Impact of Biodiesel

Wright, Monica Elizabeth 06 December 2012 (has links)
Mobile source emissions are a major contributor to global and local air pollution. Governments and regulatory agencies have been increasing the stringency of regulations in the transportation sector for the last ten years to help curb transportation sector air pollution. The need for regulations has been emphasized by scientific research on the impacts from ambient pollution, especially research on the effect of particulate matter on human health. The particulate emissions from diesel vehicles, diesel particulate matter (DPM) is considered a known or probable carcinogen in various countries and increased exposure to DPM is linked to increased cardiovascular health problems in humans. The toxicity of vehicle emissions and diesel particulate emissions in particular, in conjunction with an increased awareness of potential petroleum fuel shortages, international conflict over petroleum fuel sources and climate change science, have all contributed to the increase of biodiesel use as an additive to or replacement for petroleum fuel. The goal of this research is to determine how this increased use of biodiesel in the particular emission testing setup impacts urban air quality. To determine if biodiesel use contributes to a health or climate benefit, both the size range and general composition were investigated using a comprehensive comparison of the particulate component of the emissions in real time. The emissions from various biodiesel and diesel mixtures from a common diesel passenger vehicle were measured with a cavity ring-down transmissometer (CRDT) coupled with a condensation particle counter, a SMPS, a nephelometer, NOx, CO, CO2, and O3 measurements. From these data, key emission factors for several biodiesel and diesel fuel mixtures were developed. This approach reduces sampling artifacts and allows for the determination of optical properties, particle number concentration, and size distributions, along with several important gas phase species' concentrations. Findings indicate that biodiesel additions to diesel fuel do not necessarily have an air quality benefit for particulate emissions in this emission testing scenario. The often cited linear decrease in particulate emissions with increasing biodiesel content was not observed. Mixtures with half diesel and half biodiesel tended to have the highest particulate emissions in all size ranges. Mixtures with more than 50% biodiesel had slightly lower calculated mass for light absorbing carbon, but this reduction in mass is most likely a result of a shift in the size of the emission particles to a smaller size range, not a reduction in the total number of particles. Evaluation of the extensive optical properties from this experimental set-up indicates that biodiesel additions to diesel fuel has an impact on emission particle extinction in both visible and near-IR wavelengths. The B99 mixture had the smallest emission factor for extinction at 532 nm and at 1064 nm. For the extinction at 532 nm, the trend was not linear and the emission factor peaked at the B50 mixture. Results from intensive properties indicate that emissions from B5 and B25 mixtures have Ångström exponents close to 1, typical for black carbon emissions. The mixtures with a larger fraction of biodiesel have Ångström exponent values closer to 2, indicating more absorbing organic matter and/or smaller particle size in the emissions. Additional experimental testing should be completed to determine the application of these results and emission factors to other diesel vehicles or types of diesel and biodiesel fuel mixtures.
24

Réponses écophysiologiques à une pollution d’origine anthropique chez un organisme sentinelle et conséquences sur le fonctionnement des bassins d’infiltration / Ecophysiological responses of anthropic pollution in a sentinelle organism and consequences on infiltration basin functioning

Pigneret, Mathilde 16 March 2018 (has links)
Les populations humaines sont exposées à de très nombreux polluants. Il apparaît donc essentiel d'évaluer la toxicité de ces molécules au sein des compartiments récepteurs. En milieu urbain, de nombreux polluants (principalement hydrocarbures et métaux lourds) s'accumulent sur les surfaces imperméables (routes, toitures, parkings, bâtiments…). Ils sont remis en suspension et drainés par les eaux de pluie jusque dans les bassins d'infiltration. Ces structures ont été construites afin de réinfiltrer les eaux de ruissellement dans les nappes phréatiques sous-jacentes et de les détoxifier. Ces molécules toxiques sont capturées et accumulées au niveau des sédiments fins constitutifs des bassins, où elles peuvent atteindre des concentrations très élevées. Malgré cette forte contrainte, quelques rares invertébrés vivent dans les sédiments pollués des bassins d'infiltration, ce qui sous-entend des adaptations métaboliques, physiologiques et/ou comportementales spécifiques. L'un des plus répandus est l'oligochète aquatique Limnodrilus hoffmeisteri. Ce ver tubificidé construit des galeries (activité de bioturbation) dans les sédiments où il favorise l'activité des microorganismes sur la minéralisation de la matière organique et le recyclage des nutriments. Cette espèce présente donc un rôle essentiel dans le fonctionnement des bassins d'infiltration, et donc sur la qualité de l'eau des nappes phréatiques. Elle est aujourd'hui considérée à la fois comme une espèce sentinelle de l'état de santé de son biotope et comme un ingénieur des écosystèmes. Le premier objectif de ce travail de thèse a été de mettre en évidence les réponses écophysiologiques permettant à L. hoffmeisteri de survivre dans ces biotopes particulièrement anthropisés. Pour cela, nous avons exposé/élevé cet organisme pendant 1, 3 ou 6 mois dans des sédiments pollués issus de 3 bassins d'infiltration et un sédiment issu d'un milieu non urbanisé (sédiment témoin très peu pollué), en laboratoire. Nous avons ensuite analysé sur ce ver la survie, la consommation d'oxygène, l'état des réserves énergétiques, les concentrations de métaux lourds bioaccumulés, le stress oxydant engendré par les polluants (niveau de peroxydation lipidique) et enfin les mécanismes de protection associés (activités des principales enzymes antioxydantes). Le deuxième objectif a été de déterminer l'impact des polluants urbains sur les métabolismes aérobie et anaérobie chez L. hoffmeisteri. Pour cela, nous avons mesuré différents paramètres témoignant de l'activité mitochondriale (activités de la chaîne respiratoire mitochondriale et de l'ATP synthétase) ainsi que les concentrations des principaux produits terminaux du métabolisme anaérobie chez des vers exposés aux mêmes sédiments (4) pollués ou témoin. Cette étude a démontré que les contaminants induisent une transition partielle du métabolisme aérobie vers les voies anaérobies suite à un dysfonctionnement mitochondrial, et a aussi révélé que certains produits terminaux du métabolisme anaérobie (succinate et propionate) constituent des marqueurs pertinents de la pollution urbaine. Enfin, le troisième objectif de cette thèse a été d'évaluer l'impact d'une pollution d'origine anthropique sur l'activité d'ingénierie de L. hoffmeisteri (i.e. sur son rôle dans le fonctionnement des bassins d'infiltration). Pour cela, nous avons mesuré pendant 1 mois le comportement de fouissage de ce ver bioturbateur par tomographie aux rayons X dans des microcosmes contenant des sédiments pollués ou non. De plus, des mesures régulières des flux de nutriments, d'oxygène dissous, de CO2 et de CH4 au cours de l'expérimentation ont permis d'évaluer l'influence du taux de contamination sur le recyclage des nutriments dans nos systèmes expérimentaux. Ces mesures ont été effectuées à la fois dans des systèmes colonisés par L. hoffmeisteri, mais aussi dans des systèmes sans faune, afin de quantifier précisément le rôle de ces organismes ingénieurs / Human populations are exposed to numerous pollutants. It is now necessary to evaluate the toxicity of urban contaminants in receptor ecosystems. In anthropized areas, many pollutants (mainly hydrocarbons and heavy metals) accumulate on the impervious surfaces (roads, parks, buildings, rooftops…). During a rainfall event, these compounds are re-suspended and drained up to stormwater infiltration basins. These structures were built to detoxify and to infiltrate runoff water to underlying groundwater. Toxic compounds are captured and accumulated in the fine sediment layer of the infiltration basins, where their concentrations may achieve important concentrations. Despite this harsh constraint, a few invertebrates inhabit stormwater basin sediments and have developed specific metabolic, physiological and/or behavioural adaptations. One of the most spread is the oligochaeta Limnodrilus hoffmeisteri. This tubificid worm burrows galleries (bioturbation activity) in sediments where it enhances the organic matter mineralization and the nutrients recycling. This species has an essential role in the infiltration basin functioning and on groundwater quality. L. hoffmeisteri is considered both as a sentinel species of ecosystem health and an engineer species. The first aim of this work was to highlight the ecophysiological responses that allow L. hoffmeisteri to survive in these harsh conditions. We exposed this organism during 1, 3 or 6 months to polluted sediments (from 3 infiltration basins), under laboratory conditions. Then, we measured the survival, the oxygen consumption, the energy body stores, the oxidative stress induced by urban pollutants (through the lipid peroxidation level), and the antioxidant defence mechanisms (the activity of the antioxidant enzymes) in L. hoffmeisteri. The same analyses were realized on worms incubated 1 to 6 months in a sediment from a non-urbanized environment (considered as a low-polluted/control sediment). The second objective of the present work was to determine the impact of urban pollutants on aerobic and anaerobic metabolisms in L. hoffmeisteri. We measured several mitochondrial parameters (the mitochondrial respiratory chain activity and the ATP production rate) and anaerobic end product concentrations in worms exposed to the 4 same sediments (polluted or not). This study demonstrated that urban pollutants induced a shift from aerobic to the anaerobic metabolism, linked to a mitochondrial dysfunctioning. Moreover, this study also showed that two anaerobic end products (succinate and propionate) constitute relevant biomarkers of urban pollution. Lastly, the third goal of this thesis was to evaluate the impact of an anthropic pollution on the engineering activity of L. hoffmeisteri (i.e. its role in the infiltration basin functioning). To this end, we measured during 1 month the burrowing activity of this tubificid worm using X-ray tomography, in microcosms containing slightly or highly polluted sediments. We measured nutrients fluxes, dissolved oxygen, CO2 and CH4 concentrations during the experiment to determine the influence of the pollution rate on nutrients recycling. These measurements were also realized in microcosms with or without worms, to quantify the functional role of engineer organisms
25

Investigação de contaminantes mutagênicos de matrizes ambientais em área de risco ecotoxicológico

Lemos, Andréia Torres de January 2011 (has links)
A crescente introdução de variados poluentes em matrizes ambientais de áreas urbanas causa prejuízos ao ecossistema e dificulta as medidas de controle ambiental. Essas substâncias, após liberadas, se distribuem e interagem de acordo com suas características e as do meio receptor. Indicadores precoces de contaminação permitem a adoção de medidas preventivas aos danos causados pela poluição ambiental. O presente estudo teve por objetivo investigar a ação de substâncias genotóxicas em diferentes frações de material particulado atmosférico e solos, analisando a presença de contaminantes orgânicos e inorgânicos. Para este fim, foi empregado o ensaio Salmonella/microssoma em amostras de áreas urbanas caracterizadas como urbano-residencial e urbano-industrial, na cidade de Rio Grande, RS. Amostras de material particulado atmosférico (PTS e PM2,5) e de solo superficial (composição granulométrica total e fração <0,5mm) foram preparadas por diferentes métodos de extração. Este estudo apresenta uma primeira caracterização de PM2,5, através do ensaio Salmonella/microssoma, no Brasil. O estudo de extratos orgânicos e aquosos de PTS e PM2,5 evidenciou a presença de compostos metálicos na fração aquosa, potencialmente biodisponíveis, bem como maior risco de exposição associado à fração de compostos orgânicos das partículas finas. A mutagênese foi detectada, mesmo em amostras de particulados que se encontravam em conformidade com os parâmetros de qualidade recomendados. A análise das extrações ácidas dos solos mostrou que as chuvas da região podem atuar como rota de contaminação ambiental, com risco adicional na disponibilização de substâncias tóxicas nos eventos de precipitação ácida. O estudo mostrou que o emprego do solo com mínima alteração é mais apropriado para os ensaios de mutagênese. A utilização conjunta de diferentes métodos de extração de compostos orgânicos e inorgânicos permite uma avaliação integradora da qualidade de matrizes ambientais complexas, favorecendo a adoção de medidas preventivas para a proteção do ecossistema. / The increasing introduction of different pollutants into the environmental matrices of urban areas damages the ecosystem and makes it difficult to perform environmental control. After these substances are released, they are distributed and interact according to their own characteristics and those of the receiving environment. Early indicators of contamination allow measures to be adopted to prevent damage caused by environmental pollution. The purpose of this study was to investigate the action of genotoxic substances in different fractions of atmospheric particulate matter and soils, analyzing the presence of organic and inorganic contaminants. For this, the Salmonella/microsome assay was used on samples of urban areas characterized as urban-residential and urban-industrial, in the city of Rio Grande, RS. Samples of atmospheric particulate matter (TSP and PM2.5) and of surface soil (total grain size composition and fraction <0.5mm) were prepared using different extraction methods. This study presents a first characterization of PM2.5 in Brazil, through the Salmonella/microsome assay. The study of organic and aqueous extracts of TSP and PM2.5 showed the presence of potentially bioavailable metallic compounds in the aqueous fraction, as well as a greater risk of exposure associated with the fraction of organic compounds of the fine particles. Mutagenesis was detected even in samples of particulates that were in accordance the recommended quality parameters. Analysis of acid extractions from the soils showed that rainfall in the region may act as an environmental contamination route, with an additional risk of making toxic substances available in acid precipitation events. The study showed that the use of minimally altered soil is more appropriate for mutagenesis assays. The joint use of different methods for organic and inorganic compound extractions allows an integrated evaluation of the quality of complex environmental matrices, favoring the adoption of preventive measures to protect the ecosystem.
26

Investigação de contaminantes mutagênicos de matrizes ambientais em área de risco ecotoxicológico

Lemos, Andréia Torres de January 2011 (has links)
A crescente introdução de variados poluentes em matrizes ambientais de áreas urbanas causa prejuízos ao ecossistema e dificulta as medidas de controle ambiental. Essas substâncias, após liberadas, se distribuem e interagem de acordo com suas características e as do meio receptor. Indicadores precoces de contaminação permitem a adoção de medidas preventivas aos danos causados pela poluição ambiental. O presente estudo teve por objetivo investigar a ação de substâncias genotóxicas em diferentes frações de material particulado atmosférico e solos, analisando a presença de contaminantes orgânicos e inorgânicos. Para este fim, foi empregado o ensaio Salmonella/microssoma em amostras de áreas urbanas caracterizadas como urbano-residencial e urbano-industrial, na cidade de Rio Grande, RS. Amostras de material particulado atmosférico (PTS e PM2,5) e de solo superficial (composição granulométrica total e fração <0,5mm) foram preparadas por diferentes métodos de extração. Este estudo apresenta uma primeira caracterização de PM2,5, através do ensaio Salmonella/microssoma, no Brasil. O estudo de extratos orgânicos e aquosos de PTS e PM2,5 evidenciou a presença de compostos metálicos na fração aquosa, potencialmente biodisponíveis, bem como maior risco de exposição associado à fração de compostos orgânicos das partículas finas. A mutagênese foi detectada, mesmo em amostras de particulados que se encontravam em conformidade com os parâmetros de qualidade recomendados. A análise das extrações ácidas dos solos mostrou que as chuvas da região podem atuar como rota de contaminação ambiental, com risco adicional na disponibilização de substâncias tóxicas nos eventos de precipitação ácida. O estudo mostrou que o emprego do solo com mínima alteração é mais apropriado para os ensaios de mutagênese. A utilização conjunta de diferentes métodos de extração de compostos orgânicos e inorgânicos permite uma avaliação integradora da qualidade de matrizes ambientais complexas, favorecendo a adoção de medidas preventivas para a proteção do ecossistema. / The increasing introduction of different pollutants into the environmental matrices of urban areas damages the ecosystem and makes it difficult to perform environmental control. After these substances are released, they are distributed and interact according to their own characteristics and those of the receiving environment. Early indicators of contamination allow measures to be adopted to prevent damage caused by environmental pollution. The purpose of this study was to investigate the action of genotoxic substances in different fractions of atmospheric particulate matter and soils, analyzing the presence of organic and inorganic contaminants. For this, the Salmonella/microsome assay was used on samples of urban areas characterized as urban-residential and urban-industrial, in the city of Rio Grande, RS. Samples of atmospheric particulate matter (TSP and PM2.5) and of surface soil (total grain size composition and fraction <0.5mm) were prepared using different extraction methods. This study presents a first characterization of PM2.5 in Brazil, through the Salmonella/microsome assay. The study of organic and aqueous extracts of TSP and PM2.5 showed the presence of potentially bioavailable metallic compounds in the aqueous fraction, as well as a greater risk of exposure associated with the fraction of organic compounds of the fine particles. Mutagenesis was detected even in samples of particulates that were in accordance the recommended quality parameters. Analysis of acid extractions from the soils showed that rainfall in the region may act as an environmental contamination route, with an additional risk of making toxic substances available in acid precipitation events. The study showed that the use of minimally altered soil is more appropriate for mutagenesis assays. The joint use of different methods for organic and inorganic compound extractions allows an integrated evaluation of the quality of complex environmental matrices, favoring the adoption of preventive measures to protect the ecosystem.
27

Estudo da variabilidade sazonal da profundidade óptica do aerossol em São Paulo a partir de radiômetros MFRSR / Study of the seasonal variability of the aerosol optical depth in São Paulo using MFRSR radiometers.

André Cozza Sayão 27 March 2008 (has links)
A avaliação dos efeitos dos aerossóis em relação ao balanço radiativo local e global bem como o impacto sobre a saúde humana, principalmente em grandes centros urbanos, demanda que se conheça de forma precisa a sua concentração e distribuição espaço-temporal. Neste contexto, o monitoramento acurado de longo prazo por estações instaladas ao redor do mundo tornou-se um desafio e uma necessidade para várias áreas do conhecimento. Classicamente as estações utilizam a técnica de fotometria solar para inferir a concentração e a distribuição de tamanho dos aerossóis através da profundidade óptica do aerossol (POA) e do coeficiente de Ångström . No presente trabalho é sugerida uma metodologia para estimar POA e do coeficiente de Ångström através de quatro canais espectrais de radiômetros do tipo Multi-Filter Rotating Shadowband Radiometer (MFRSR) que operam em São Paulo desde 1999. Estas estimativas foram avaliadas em relação à rede AErosol RObotic NETwork (AERONET) entre os anos de 2004 a 2006. Os resultados mostram que, em termos de variabilidade temporal da POA, há boa concordância entre os diferentes instrumentos. Entretanto, são encontradas diferenças médias sistemáticas da ordem de 0,03 na magnitude da POA em três dos quatro canais analisados, enquanto que o valor sugerido pela OMM para uma atmosfera limpa é de no máximo 0,02. Este resultado aponta que a metodologia empregada nos MFRSR fornece valores de boa qualidade. Ainda neste trabalho, foram relacionadas variáveis meteorológicas coletadas pela Estação Meteorológica do IAG-USP com a POA e o do coeficiente de Ångström estimados neste trabalho. Observou-se uma relação linear entre o coeficiente de Ångström e a umidade relativa (UR), indicando um crescimento do tamanho médio dos aerossóis que integram um grupo com 0,20<POA<=0,60 no canal 415nm com o aumento da umidade relativa. Acredita-se que este grupo tenha predominância de aerossóis de fontes locais. As medidas de longo prazo permitiram também caracterizar, em conjunto com estimativas espaciais de POA pelo sensor Moderate Resolution Imaging Spectroradiometer (MODIS) a bordo do satélite Terra, a influência do transporte de aerossóis de queimadas da região amazônica e do Brasil central em São Paulo, na série de dados analisados. Estes eventos contribuem para o aumento significativo da POA sobre a região metropolitana e trazem partículas ligeiramente menores que as emitidas por fontes locais. / The evaluation of the aerosol effects to the local and global radiation budget, as well as the impact on human health, particularly in large urban centers, demands knowing accurately their concentration and spatial-temporal distribution. In this context, the accurate long term monitoring from ground based stations installed around the world has become a challenge and a necessity for various areas of knowledge. Classically, the stations use the technique of Sun photometry to infer the concentration and size distribution of aerosols through the aerosol optical depth (AOD) and Ångström coefficient . In this paper we suggest a methodology to estimate AOD and Ångström coefficient through four channels of Multi-Filter Rotating Shadowband Radiometers (MFRSR) operating in Sao Paulo since 1999. These estimates were compared to the results of the AErosol RObotic NETwork (AERONET) between the years of 2004 to 2006. The results showed that the MFRSR can represent well the temporal variability of the AOD, but systematic differences were found with mean values of about 0.03 in AOD, in three of the four analyzed channels. The value suggested by WMO for clean air is at most 0.02. This result indicates that the methodology employed in MFRSR provides values of quality good. Also in this study, meteorological influences on the aerosol optical properties were analyzed. The meteorological variables were monitored at the Meteorological Station of the IAG-USP There was a linear relationship between Ångström coefficient and relative humidity (RH), indicating a growth of the average size of aerosols within a group with 0.20<AOD<=0.60, in the channel 415 nm, with increasing relative humidity. It is believed that this group has predominance of aerosols from local sources. Long term measurements also helped to characterize, together with spatial estimates of AOD by the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the Terra satellite, the influence of the transport of aerosol particles from biomass burning from the Amazon region to São Paulo. It was observed that these events contribute to significant increase in AOD on the metropolitan region and bring slightly smaller particles than the emitted by local sources.
28

The Landscape Legacies of Gas Drilling in North Texas

Sakinejad, Michael Cyrus 05 1900 (has links)
In North Texas, the Barnett Shale underlies large areas of the Dallas-Fort Worth Metroplex (DFW), which magnifies debates about the externalities of shale gas development (SGD). Continued demand for natural gas and expansive urbanization in DFW will cause more people to come in contact with drilling rigs, gas transport, and other urban shale gas landscapes. Thousands of gas wells within the DFW region occupy a large, yet scattered land surface area. DFW city planners, elected officials, and other stakeholders must deal with current and future urban growth and the surface impacts that are associated with gas development. This research examines how shale gas landscapes affect urban land uses, landscapes, and patterns of development in DFW. The study focuses on multiple fast growing DFW municipalities that also have high numbers of gas well pad sites. This study asks what are the spatial characteristics of gas well production sites in DFW and how do these sites vary across the region; how do gas well production sites affect urban growth and development; and how are city governments and surface developers responding to gas well production sites, and what are the dominant themes of contestation arising around gas well production sites and suburban growth?
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Compréhension du fonctionnement biologique et physico-chimique d'un biofiltre végétalisé pour le traitement de polluants atmosphériques urbains gazeux / Understanding of biological and physico-chemical operation of planted biofilter for the treatment of urban gaseous pollutants

Rondeau, Anne 01 February 2013 (has links)
En ville, les parcs de stationnement couverts représentent un milieu confiné dans lequel s'accumule une pollution importante et complexe. Ils constituent également une source de pollution pour leurs abords puisqu'aucune obligation de traitement n'est imposée sur la qualité de l'air rejeté dans l'atmosphère par les systèmes de ventilation. Dans le cadre du traitement de l'air, l'utilisation d'un biofiltre végétalisé, faisant intervenir des bactéries et des plantes en association, constitue une solution innovante contribuant à l'amélioration de la qualité de l'air en ville en réduisant la dispersion de polluants gazeux dans l'atmosphère. Dans un contexte de « recherche et développement », l'objectif est de comprendre le fonctionnement biologique et physico-chimique du biofiltre dans le but d'en améliorer la maitrise opérationnelle. Le caractère innovant de l'étude porte sur le traitement d'importants volumes d'air viciés contenant de faibles concentrations de polluants, tels que les NOx et les COV (de l'ordre de 100 à 200 µg/m3), par un biofiltre planté d'épaisseur modeste. L'utilisation d'une unité pilote de biofiltration a permis d'évaluer l'influence de la présence de plante, ainsi que la nécessité d'un apport d'engrais, sur les capacités d'épuration d'un tel système. Afin d'optimiser les volumes d'air traités tout en limitant l'empreinte au sol des biofiltres végétalisés, la vitesse de passage de l'air a été augmentée et l'épaisseur de garnissage réduite. Le rôle des bactéries indigènes a été caractérisé par une étude fonctionnelle des communautés bactériennes impliquées dans la dégradation des NOx et des TEX d'une part, et par une étude quantitative et qualitative de la communauté bactérienne totale, en utilisant des approches de biologie moléculaire, telles que l'amplification par PCR en temps réel et le pyroséquençage à partir de l'ADN métagénomique / In town, underground car parks are confined spaces in witch large and complex pollution are accumulated. They are also a source of contamination of the external environment since the treatment of the air pumped out by ventilation system sis not regulated. In the framework of air treatment, using planted biofilter, combining bacteria and plants, is an innovative solution contributing to the improvement of urban air quality by reducing the dispersion of gaseous pollutants in the atmosphere. In a « research and development » context, the objective is to understand the biological and physico-chemical operation for improving operational control. This innovative study focuses on the treatment of high volumes of air containing a low concentrations of pollutants, such as NOx, VOCs (about 100 à 200 µg.m-3) through a thin planted biofilter. The use of a pilot-scale unit of biofiltration allowed to evaluate the influence of the plant, as well as the necessity of a fertilization, on the removal efficiency of such a system. In order to maximize the volumes of treated air while limiting the footprint of the planted biofilters, the superficial gas velocity has been increased and the thickness of the packing material decreased. The indigenous bacteria have been characterized by a functional study of the bacterial communities involved in the degradation of NOx and TEX on one part, and by a quantitative and qualitative study of the total bacterial community on the other part, by using molecular biology approaches, such a real-time PCR amplification, and pyrosequencing from metagenomic DNA. Results on pilot-scale unit have shown a removal efficiency greater than 97%, in all environmental conditions tested. Consequently, it seems possible to treat high volumes of air containing low concentrations of TEX through a thin planted biofilter. The presence of plants does not seem to have short-term impacts on the removal efficiency when a fertilizer promotes the nitrogen availability in the packing material. The evaluation of the global microbiological functioning showed the potential of microbial communities in the biodegradation of NOx and TEX in planted biofilters. The indigenous bacterial communities of the packing material and the mound of soil are rapidly able to adapt to the functioning conditions of such a system
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A Cumulative Damage Approach to Modeling Atmospheric Corrosion of Steel

Rose, David Harry January 2014 (has links)
No description available.

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