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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.
71

Nitrato na solução do solo e na água de fontes para consumo humano numa microbacia hidrográfica produtora de fumo / Nitrate in the soil solution and in the water of wells used for human consumption in a tobacco producing watershed

Kaiser, Douglas Rodrigo 24 November 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The tobacco production system in Rio Grande do Sul state is mainly developed in small farms, using shallow soils in steep slope. In these areas rivers are born forming small watersheds. The areas are fragilized by use of inappropriate tillage systems causing soil degradation. To compensate this, new areas are included in the production system, after deforestation and not following environmental legislations rules. In order to maintain yield of the degraded areas is needed high fertilization rates and agrochemical application, following a technology package recommended by tobacco industry. Adding to this the fact, that tobacco has a low efficiency of nutrient use. The objective of this study, was monitored the nitrate concentration of soil solution in several soil management and use and in two domestic well used for drinking water. The study was carried out at Arroio Lino watershed, located in Nova Boemia district of Agudo county, state of Rio Grande do Sul. The area of the watershed presents high steepness and it prevails Entisols and mollisols.The soil solution was extracted with tension lysimeters equipped with ceramic porous cup installed at rooting depth (0,15 or 0,2 m) and below this depth (0,3 or 0,5 m), after the main rains happened during the tobacco cycle.The precipitation data were obtained from an automated meteorological station installed at central part of watershed. In 2004/2005 agricultural year, the nitrate concentration was measured in lysimeters installed in a soil management experiment, in an Entisol, including tobacco no-tillage (NT), minimum tillage (MT) and conventional tillage (CT). In 2005/2006 agricultural year, the nitrate concentration was measured in five transects distributed in several places of the watershed, including tobacco plantation, forest and grass field. Two domestic wells located at lower position of landscape were monitored to nitrate concentration. One of those was located at a position which had above it 15 m stripe of forest and after had tobacco plantation, and the other had no tobacco plantation at position above it. At the points of each transect was evaluated bulk density, soil porosity, saturated hydraulic conductivity and soil water retention curve. The soil tillage systems experiment showed higher value of nitrate concentration after starter fertilization application and decreased along of plant cycle, with content varying from 8 to 226 mg L-1. The highest concentration was observed at MT and lowest at NT. The average nitrate concentration in the rooting zone (0,2 m) was 75 for PD, 95 for MT and 49 mg L-1 for CT. Below the rooting zone, the average was 58 for NT, 108 for MT and 36 mg L-1 for CT. The soil in the transects presented low bulk density, low water storage, high porosity and high saturated hydraulic conductivity. The nitrate reached depths bellow rooting zone and its concentration was higher at tobacco plantation than at forest and grass field, reaching values as high as 80 mg L-1 in tobacco plantation. The well located below tobacco plantation had higher nitrate concentration, overcoming the critical limit of 10 mg L-1 in some periods. / A fumicultura no Rio Grande do Sul é desenvolvida em propriedades familiares em regiões ecologicamente frágeis, com solos rasos e alta declividade. Nessas regiões nascem rios e ocorre a formação de pequenas bacias hidrográficas. As áreas são fragilizadas por sistemas de manejo do solo impróprios para aquelas condições e, para manter a capacidade produtiva, recebem anualmente altas doses de fertilizantes e agrotóxicos, seguindo-se um pacote tecnológico difundido pelas agroindústrias fumageiras, que desconsidera as condições ambientais e os atributos do solo. O objetivo deste trabalho foi monitorar a concentração de nitrato na solução do solo, sob diferentes condições de uso e manejo, e na água de duas fontes usadas para o abastecimento doméstico, e relacioná-las com a influência antrópica. O estudo foi conduzido na microbacia hidrografia do Arroio Lino, localizada no distrito de Nova Boêmia, Agudo-RS. A área da microbacia apresenta alta declividade e nela predominam Neossolos e Chernossolos. A solução do solo foi extraída com lisímetros de tensão com cápsulas porosas na região da zona radicular do fumo (0,15 a 0,20 m) e abaixo dessa (0,30 a 0,50 m), logo após as principais chuvas ocorridas durante o ciclo do fumo. Os dados de precipitação foram obtidos de uma micro-estação meteorológica automatizada instalada na microbacia. Na safra de 2004/2005, os lisímetros foram instalados num experimento, sob Neossolo Litólico, com sistemas de manejo para a implantação da cultura do fumo, sendo monitorado o sistema plantio direto (PD), cultivo mínimo (CM) e preparo convencional (PC). Na safra de 2005/2006, os lisímetros foram instalados em cinco transeções distribuídos na paisagem, abrangendo lavouras de fumo, mata e campo nativo. As duas fontes monitoradas estavam localizadas na encosta, sendo que uma delas apresentava uma faixa de 15 m de mata na sua volta e, acima dessa, era cultivado fumo. A outra fonte estava protegida pela mata e não apresentava influência antrópica nas suas proximidades. Nos pontos de cada transeção, avaliaram-se a densidade do solo, porosidade do solo, condutividade hidráulica saturada e curva de retenção de água. Nos sistemas de manejo do solo os teores de nitrato variaram de 8 a 226 mg L-1 e foram maiores após a adubação de base e decresceram ao longo do ciclo. Os níveis mais altos foram obtidos no CM e os menores no PD. Os teores médios de nitrato na zona radicular foram de 75 no PD, 95 no CM e 49 mg L-1 no PC. Abaixo da zona radicular os teores médios foram de 58 no PD, 108 no CM e 36 mg L-1 de nitrato no PC. O solo nas transeções apresentou baixa densidade, baixa capacidade de armazenamento de água, alta porosidade e alta condutividade hidráulica saturada. O nitrato atingiu profundidades abaixo da zona de exploração radicular (0,5m). Os teores de nitrato foram superiores nas lavouras em relação ao campo e à mata nativa, atingindo 80 mg L-1 nas áreas com fumo. A fonte (poço) que se encontrava abaixo das lavouras de fumo teve maiores concentrações de nitrato, superando o limite crítico de 10 mg L-1 em alguns períodos.
72

Ocorrência de hormônios nas águas superficiais da Região Hidrográfica do Médio Curso do Rio Paraíba.

AMORIM, Marlon Leal Cabral Menezes de. 27 July 2018 (has links)
Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-07-27T13:49:44Z No. of bitstreams: 1 MARLON LEAL CABRAL MENEZES DE AMORIM - DISSERTAÇÃO (PPGECA) 2016.pdf: 1649464 bytes, checksum: a4b0872dbeecb56cc3c49eb0438ad7c7 (MD5) / Made available in DSpace on 2018-07-27T13:49:44Z (GMT). No. of bitstreams: 1 MARLON LEAL CABRAL MENEZES DE AMORIM - DISSERTAÇÃO (PPGECA) 2016.pdf: 1649464 bytes, checksum: a4b0872dbeecb56cc3c49eb0438ad7c7 (MD5) Previous issue date: 2016-08-26 / Capes / Os hormônios naturais 17β-estradiol, estrona e o hormônio sintético 17α-etinilestradiol vêm sendo detectados em águas superficiais, principalmente devido ao fato dos atuais processos de tratamento de água e esgotos serem incapazes de removê-los, sendo descarregados em corpos receptores. O monitoramento da ocorrência dessas substâncias se mostra necessário, pois suas presenças podem causar danos à saúde humana e ambiental (organismos aquáticos e terrestres). No presente trabalho, foi realizado o desenvolvimento e validação do método, por meio de cromatografia líquida de alta eficiência (HPLC) com detector com comprimento de onda variável UV/Vis, para a determinação simultânea desses hormônios em amostras de água e esgoto da região hidrográfica do médio curso do rio Paraíba. A análise cromatográfica foi realizada em modo isocrático, fase móvel acetonitrila e água (50:50), coluna C18, vazão 1 mL/min, injeção 10 μL, comprimento de onda de 200 nm, temperatura do equipamento de 40°C. O método desenvolvido apresentou uma boa resposta quanto à seletividade dos hormônios e linearidade com coeficiente de determinação (r2) entre 0,9943 e 0,9951. Os limites de quantificação estimados foram de 90,45 μg/L para o 17β-estradiol, 96,76 μg/L para o 17α etinilestradiol e 96,19 μg/L para a estrona, sendo os limites de detecção de, respectivamente, 60,27 μg/L, 65,12 μg/L e 64,16 μg/L. A precisão e a robustez apresentaram desvios padrões relativos inferiores a 5%. A metodologia proposta mostrou-se adequada para a determinação de hormônios estrogênios em amostras de águas. Com relação à análise nas amostras de água e esgoto coletada, não foi detectado a presença de hormônio em nenhuma das amostras nas concentrações mínimas de detecção e quantificação do método desenvolvido. / The natural hormones 17β - estradiol and estrone and the synthetic hormone 17α - ethinylestradiol have been detected in surface water, mainly due to the current water and wastewater treatment processes being unable to remove them, leading them to be discharged into receiving water bodies. Monitoring the occurrence of these substances in water is currently very necessary because their presence can cause harm to human health and the environment (aquatic and terrestrial organisms). This work describes the development and validation of a method for the simultaneous determination of these hormones in water samples by means of high-performance liquid chromatography (HPLC), from the simultaneous determination of these hormones in water samples and sewage from the river basin of the middle course of the river Paraíba. The chromatographic analyses were performed in an isocratic mode, being the mobile phase acetonitrile and water (50:50), using a C18 column, flow rate of 1mL/min, 10 μL-injection volume, wavelength of 200 nm and temperature of 40 °C. The method showed a good response on the hormone selectivity and linearity of calibration curves with coefficients of determination (r2) between 0.9943 and 0.9951. The estimated quantification limits were 90.45 μg/L for 17β - estradiol, 96.76 μg/L for the 17α ethinylestradiol and 96.19 μg/L for estrone, and the detection limits 60.27 μg/L, 65.12 μg/L and 64.16 μg/L, respectively. The precision and robustness presented relative standard deviations of less than 5 %. The proposed methodology was appropriate for the determination of estrogen hormones in water samples. Regarding the analysis on water collected and sewage was nor detected the presence of the hormone in any of the samples at the minimum concentrations of detection and quantification method developed.
73

Estudo da alteração na absorção da luz monocromática (transmitância) como parâmetro de contaminação do mar por hidrocarbonetos

Sieczka Junior, Edson Luiz 27 June 2013 (has links)
CAPES / O monitoramento em tempo real da água do mar em ambientes críticos, como na entrada de portos e de canais de navegação, é necessário para evitar grandes contaminações do meio ambiente marinho, principalmente em regiões costeiras. A contaminação mais recorrente é por derramamento de hidrocarbonetos. Um indicativo de contaminação por óleo, em tempo real, viabiliza a atuação imediata dos setores responsáveis. Tal medida pode evitar que as impurezas se espalhem por uma área maior, o que torna o processo de limpeza e descontaminação mais rápido e eficaz. Este estudo visa detectar alterações no comportamento físico da água do mar quando existir contaminação por hidrocarbonetos. O parâmetro físico a ser estudado é a variação na curva de transmitância da água do mar, com específicos comprimentos de onda, quando existir contaminação na amostra. A variação da absorção da onda eletromagnética detectada pelo foto sensor pode indicar que a amostra de água esteja contaminada por hidrocarbonetos. O equipamento base para a tomada de dados das curvas de transmitância é o espectrofotômetro, que tem como característica a capacidade de realizar uma varredura em uma faixa de comprimento de onda eletromagnética compreendida entre 190 nm a 1100 nm. A avaliação dos resultados é feita utilizando uma placa de aquisição do espectro de um LED de 400 nm. Dois métodos foram realizados utilizando a mesma fonte de radiação, o primeiro com incidência horizontal da luz na amostra de água (próximo à superfície) e o segundo com incidência vertical, submetendo a radiação à absorção causada pela coluna de água e contaminante (gasolina e querosene). Os resultados obtidos neste trabalho apresentam uma queda bem significativa da transmitância em função do aumento da concentração de poluente (hidrocarbonetos) na água, nas faixas mais pertinentes de cada substância, com suas diferentes estruturas moleculares. O ponto do espectro de maior sensibilidade para este hidrocarboneto na medição da transmitância está em 360 nm. Utilizando a lei de Lambert-Beer, foi calculada a correlação exponencial dos pontos obtidos com um determinado comprimento de onda, em 360 nm esta correlação é superior a 99%. O método utilizado e os resultados levantados possibilitam o desenvolvimento e aplicação de um sensor óptico para sensoriamento da água do mar baseado na variação da absorção da luz em função do aumento da concentração de contaminantes (hidrocarbonetos), e a utilização da lei de Lambert-Beer para estimar a concentração deste produto na água. / The real time monitoring of seawater in critical environments such as ports entrances and navigation channels is needed in order to avoid major contaminations of the marine environment especially in coastal regions. The most recurrent contamination is hydrocarbon spills. A real time contamination indicator enables immediate action from the responsible sectors. Such measurement might prevent impurities from spreading into a greater area, resulting in faster and more effective cleaning and decontamination process. This study aims to detect changes in the physical behavior of the sea water when hydrocarbon contamination exists. The physical parameter under study is the variation in the transmittance curve of seawater, with specific wavelengths, when there is contamination in the sample. The absorption variation of the electromagnetic wave detected by the photo sensor can indicate that the water sample is contaminated by hydrocarbons. The base equipment for collecting data from the transmittance curves is the spectrophotometer, which is able to perform a scan on an electromagnetic wavelength range between 190 nm to 1100 nm. Two methods were performed using the same radiation source, the first one with horizontal light incidence into the water sample (near-surface) and the second one with vertical incidence, subjecting radiation to absorption caused by the water column and contaminant (gasoline and kerosene). The results obtained in this study show a significant decrease of transmittance in function of the increase in concentration of pollutant (hydrocarbon) in the water, in the more relevant ranges of each substance, with their different molecular structures. The hydrocarbon used in the evaluation of both methods validation was gasoline. The spectrum point of greater sensitivity in measuring the hydrocarbon transmittance is in 360 nm. Using the Lambert-Beer law it was calculated exponential correlation of points obtained with a specific wavelength, in 360 nm this correlation is greater than 99%. The method and results raised enabled the development and application of an optical sensor for sensing seawater according to the variation of light absorption in function of the increasing contaminants concentration (hydrocarbons), and using the Lambert-Beer law to estimating the concentration of product in water.
74

Estudo da alteração na absorção da luz monocromática (transmitância) como parâmetro de contaminação do mar por hidrocarbonetos

Sieczka Junior, Edson Luiz 27 June 2013 (has links)
CAPES / O monitoramento em tempo real da água do mar em ambientes críticos, como na entrada de portos e de canais de navegação, é necessário para evitar grandes contaminações do meio ambiente marinho, principalmente em regiões costeiras. A contaminação mais recorrente é por derramamento de hidrocarbonetos. Um indicativo de contaminação por óleo, em tempo real, viabiliza a atuação imediata dos setores responsáveis. Tal medida pode evitar que as impurezas se espalhem por uma área maior, o que torna o processo de limpeza e descontaminação mais rápido e eficaz. Este estudo visa detectar alterações no comportamento físico da água do mar quando existir contaminação por hidrocarbonetos. O parâmetro físico a ser estudado é a variação na curva de transmitância da água do mar, com específicos comprimentos de onda, quando existir contaminação na amostra. A variação da absorção da onda eletromagnética detectada pelo foto sensor pode indicar que a amostra de água esteja contaminada por hidrocarbonetos. O equipamento base para a tomada de dados das curvas de transmitância é o espectrofotômetro, que tem como característica a capacidade de realizar uma varredura em uma faixa de comprimento de onda eletromagnética compreendida entre 190 nm a 1100 nm. A avaliação dos resultados é feita utilizando uma placa de aquisição do espectro de um LED de 400 nm. Dois métodos foram realizados utilizando a mesma fonte de radiação, o primeiro com incidência horizontal da luz na amostra de água (próximo à superfície) e o segundo com incidência vertical, submetendo a radiação à absorção causada pela coluna de água e contaminante (gasolina e querosene). Os resultados obtidos neste trabalho apresentam uma queda bem significativa da transmitância em função do aumento da concentração de poluente (hidrocarbonetos) na água, nas faixas mais pertinentes de cada substância, com suas diferentes estruturas moleculares. O ponto do espectro de maior sensibilidade para este hidrocarboneto na medição da transmitância está em 360 nm. Utilizando a lei de Lambert-Beer, foi calculada a correlação exponencial dos pontos obtidos com um determinado comprimento de onda, em 360 nm esta correlação é superior a 99%. O método utilizado e os resultados levantados possibilitam o desenvolvimento e aplicação de um sensor óptico para sensoriamento da água do mar baseado na variação da absorção da luz em função do aumento da concentração de contaminantes (hidrocarbonetos), e a utilização da lei de Lambert-Beer para estimar a concentração deste produto na água. / The real time monitoring of seawater in critical environments such as ports entrances and navigation channels is needed in order to avoid major contaminations of the marine environment especially in coastal regions. The most recurrent contamination is hydrocarbon spills. A real time contamination indicator enables immediate action from the responsible sectors. Such measurement might prevent impurities from spreading into a greater area, resulting in faster and more effective cleaning and decontamination process. This study aims to detect changes in the physical behavior of the sea water when hydrocarbon contamination exists. The physical parameter under study is the variation in the transmittance curve of seawater, with specific wavelengths, when there is contamination in the sample. The absorption variation of the electromagnetic wave detected by the photo sensor can indicate that the water sample is contaminated by hydrocarbons. The base equipment for collecting data from the transmittance curves is the spectrophotometer, which is able to perform a scan on an electromagnetic wavelength range between 190 nm to 1100 nm. Two methods were performed using the same radiation source, the first one with horizontal light incidence into the water sample (near-surface) and the second one with vertical incidence, subjecting radiation to absorption caused by the water column and contaminant (gasoline and kerosene). The results obtained in this study show a significant decrease of transmittance in function of the increase in concentration of pollutant (hydrocarbon) in the water, in the more relevant ranges of each substance, with their different molecular structures. The hydrocarbon used in the evaluation of both methods validation was gasoline. The spectrum point of greater sensitivity in measuring the hydrocarbon transmittance is in 360 nm. Using the Lambert-Beer law it was calculated exponential correlation of points obtained with a specific wavelength, in 360 nm this correlation is greater than 99%. The method and results raised enabled the development and application of an optical sensor for sensing seawater according to the variation of light absorption in function of the increasing contaminants concentration (hydrocarbons), and using the Lambert-Beer law to estimating the concentration of product in water.
75

Ekologické problémy v Evropě v souvislosti s ekologickou politikou EU / Environmental Problems in Europe in Relation to the Environmental Policy of the European Union

Medková, Kateřina January 2009 (has links)
This thesis deals with certain environmental problems in Europe and with attempts to solve these environmental problems within the framework of the European Union. The purpose of this work is to make its readers acquainted with the scope of the EU environmental policy and Community legislation on the protection of the environment. The thesis is focused on four main subject-matters: (i) climate change as a consequence of the global warming process, (ii) air pollution and the ozone layer depletion, (iii) water contamination and (iv) soil degradation. The issue which of the environmental problems require a regional approach and which a global approach is also considered in the thesis.
76

Estudo da remoção de corantes em colunas de leito fixo utilizando como adsorventes quitosana e escama de peixe / Study of the removal of dyes in fixerd-bed column using chitosa and fish scale as adsorbents

Rocha, Allani Christine Monteiro Alves da 14 December 2011 (has links)
This study evaluated the use of the technique of adsorption in fixed-bed column using chitosan and fish scale to treat wastewater contaminated with dyes (Indigo Carmine (IC), Reactive Black 5 (RB05) and Reactive Orange 16 (RO16)). We tried to identify the interaction between the adsorbate and adsorbent and evaluate the influence of parameters: initial concentration of the dye in the effluent, bed height and flow rate in the maximum adsorption capacity. To achieve these objectives the adsorption studies were conducted in fixed bed in a glass column 9 cm and 0.6 cm in diameter. The concentration of dye in the effluent was monitored by measuring their absorbance alert of a UV-VIS spectrophotometer. The results of adsorption of the dyes on the chitosan and fish scales are presented in the form of breakthrough curves (C / Co vs. t). The adsorbed amount of each solid in the column, the balance was calculated. Starting of the curve data burst data were obtained from many different alert nonlinear models (Thomas, Model Adams-Bohart, Model Model Yan and Yoon-Nelson). Starting studies of fixed bed adsorption, is obsevou RO16 that the adsorption of the chitosan showed the highest amount adsorbed on average 30 mg g-1, the amounts found in HF and RB05 chitosan. As for the fish scale, the RB05 had the highest amount adsorbed on average 56 mg g-1, compared to IC and RO16. It was also observed that the model of Yan was suitable to represent the results obtained for the adsorption column so as to HF and RB05 RO16 in chitosan. No model was adequate to represent the results obtained for the adsorption column IC and RO16 in fish scales. Models Thomas and Adams-Bohart were the most suitable to represent the curve data burst in the adsorption RB05 fish scales. These results show that the parameters: initial concentration of dye in the effluent flow and the bed height influence the maximum quantity adsorbed and that the employed methods were adequate in view of the results obtained allow to make a clear and consistent evaluation, the performance of such adsorption technique for effluents contaminated with dyes. / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Neste trabalho foi avaliado o uso da técnica de adsorção em coluna de leito fixo utilizando quitosana e escama de peixe para tratar efluentes contaminados com corantes (Índigo Carmim (IC), Preto Reativo 5 (RB05) e Laranja Reativo 16 (RO16)). Buscou-se identificar a interação entre o adsorvente e o adsorvato e avaliar a influência dos parâmetros: concentração inicial do corante no efluente, altura do leito e vazão na capacidade máxima de adsorção. Para chegar a esses objetivos os estudos de adsorção em leito fixo foram conduzidos em uma coluna de vidro com 9 cm de altura e 0,6 cm de diâmetro. A concentração do corante no efluente foi monitorada medindo sua absorvância, atravez de um espectrofotômetro de UV-VIS. Os resultados de adsorção dos corantes sobre a quitosana e a escama de peixe são apresentados sob a forma de curvas de ruptura (C/Co versus t). A quantidade adsorvida de cada sólido na coluna, no equilibrio, foi calculada. Apartir dos dados da curva de ruptura foram obtidos dados atravez de vários modelos não linear (Modelo de Thomas, Modelo de Adams-Bohart, Modelo de Yan e o Modelo de Yoon-Nelson).Apartir dos estudos de adsorção de leito fixo, obsevou-se que a adsorção do RO16 pela quitosana apresentou a maior quantidade adsorvida, em média de 30 mg g-1, do que as quantidades encontradas para IC e RB05 em quitosana. Já para a escama de peixe, o RB05 apresentou a maior quantidade adsorvida, em média 56 mg g-1, se comparados a IC e RO16. Observou-se também que o modelo de Yan foi o mais adequado para representar os resultados obtidos para a adsorção em coluna tanto para IC quanto para RB05 e RO16 em quitosana. Nenhum modelo foi adequado para representar os resultados obtidos para adsorção em coluna do IC e RO16 em escama de peixe. Os modelos de Thomas e Adams-Bohart foram os mais adequados para representar os dados da curva de ruptura da adsorção do RB05 em escama de peixe. Esses resultados mostram que os parâmetros: concentração inicial do corante no efluente, altura do leito e vazão têm influência na quantidade máxima adsorvida e que os métodos empregados mostraram-se adequados, tendo em vista que os resultados obtidos permitiram fazer uma avaliação clara e consistente, do desempenho da adsorção como técnica de tratamento para efluentes contaminados com corantes.
77

A contaminação hídrica e os fatores críticos de sucesso na gestão em serviços de transplante de medula óssea (TMO) / The water contamination and critical success factors in management services of bone marrow transplantation (BMT)

Stangueti, Ernesto 28 November 2014 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2015-07-20T17:28:32Z No. of bitstreams: 1 Ernesto Stangueti.pdf: 896090 bytes, checksum: bf6900280e54b4847ee7b0f318f12749 (MD5) / Made available in DSpace on 2015-07-20T17:28:32Z (GMT). No. of bitstreams: 1 Ernesto Stangueti.pdf: 896090 bytes, checksum: bf6900280e54b4847ee7b0f318f12749 (MD5) Previous issue date: 2014-11-28 / Government agencies, in Brazil and in developed countries, have established guidelines for water safety in the community, in particular in the health care of immunocompromised pacients, in this case environments hospitals that receive such patients should provide higher standards for water quality by taking immediate action to prevent waterborne infections. This paper aims to assess how hospitals that perform bone marrow transplantation (BMT) manage the critical success factors in the prevention of water contamination of their patients and extract from these assessments a model of management of hospital logistics in relation to administrative processes needed for effective control of such infection. To this end, it was chosen a case study. The interviews were conducted with professional members of Commissions Infection Control in four hospitals located in São Paulo who perform BMT. The data were analyzed using the methodology of the Collective Subject Discourse (CSD) described by Lefèvre & Lefèvre (2003). The main management practices related to water contamination were: cleaning and disinfection of water tanks and bacteriological control, installation of filters for high power filtering at the point of use (taps and showers), supply of mineral water industrialized for consumption of patients of BMT unit, institution management committee comprising representatives from all areas involved in the operations of the BMT unit. Thus, this work contributes to technological and social practice through the development of a model of hospital logistics management, collaborating in preventing Related Infections at Health Care (IRAS) in units of BMT. / As agências governamentais, no Brasil e nos países desenvolvidos, têm estabelecido diretrizes para a segurança da água na comunidade, em específico nos ambientes de atendimento à saúde de pessoas imunocomprometidas, no caso, os hospitais que cuidam de tais pacientes devem fornecer padrões mais elevados para a qualidade da água tomando medidas imediatas na prevenção de infecções transmitidas pela água. Este trabalho tem como objetivo, avaliar a forma como os hospitais que realizam transplante de medula óssea (TMO) gerenciam os fatores críticos de sucesso na prevenção da contaminação hídrica de seus pacientes e extrair dessas avaliações um modelo de gestão de logística hospitalar em relação aos processos administrativos, necessários ao efetivo controle desse tipo de contaminação. Para tanto, optou-se pela estratégia de pesquisa de estudo de caso, com a realização de entrevistas junto a profissionais membros de Comissões de Controle de Infecção Hospitalar em quatro hospitais localizados no Município de São Paulo e que realizam TMO. As informações coletadas foram analisadas através da metodologia do Discurso do Sujeito Coletivo (DSC), baseado em Lefèvre & Lefèvre, (2003). Foram elencadas as principais práticas de gestão desses hospitais em relação à contaminação hídrica, sendo: limpeza e desinfecção de reservatórios de água e controle bacteriológico, instalação de filtros de alto poder de filtragem nos pontos de uso (torneiras e chuveiros), fornecimento de água mineral industrializada para consumo dos pacientes da unidade de TMO, instituição de comissão de gestão composta por representantes de todas as áreas envolvidas na manutenção das atividades da unidade de TMO. Dessa forma, este trabalho contribui com a prática tecnológica e social, através da estruturação de um modelo de gestão de logística hospitalar, colaborando na prevenção das Infecções Relacionadas à Assistência à Saúde (IRAS) em unidades de TMO.
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Groundwater Surface Trends in the North Florence Dunal Aquifer, Oregon Coast, USA

Doliber, Sarah Rebecca 01 January 2012 (has links)
The North Florence Dunal Aquifer is the only feasible source for drinking water for the coastal city of Florence, Oregon and Florence's Urban Growth Boundary. High infiltration rates and a shallow groundwater table leave the aquifer highly susceptible to contamination from septic tank effluent, storm runoff, chemical fertilizers and recreational ATV use throughout the dunes. Public interest in the quality and quantity of the aquifer water has been sparked since the City of Florence received a grant from the Environmental Protection Agency for a watershed protection and restoration project. Delineation of the shallow groundwater surface and its relationship to the surface water bodies within the dunes is crucial in protecting this drinking water source from contamination. This thesis project created a GIS representation of the shallow groundwater elevation and associated prediction error map. Surface water bodies were confirmed as window lakes into the dunal aquifer and no signs of perched aquifer conditions were observed between Holocene and Pleistocene dunes. Ground Penetrating Radar, well data provided by the city of Florence and LiDAR were the primary sources for data collection.
79

The use of bimetallic heterogeneous oxide catalysts for the Fenton reaction

Mgedle, Nande January 2019 (has links)
M.Tech. (Department of Chemistry, Faculty of Applied and Computer Sciences), Vaal University of Technology / Water contaminated with non-biodegradable organics is becoming increasing problematic as it has a hazardous effect on human health and the aquatic environment. Therefore, the removal of organic contaminants is of importance and an active heterogeneous Fenton catalyst is thus required. The literature indicates that a bimetallic oxide Fenton catalyst is more active than an iron oxide catalyst. This study focused on increasing the activity of iron-based Fenton catalysts with the addition of transition metals such as manganese, cobalt and copper and optimizing the preparation method. In this study, bimetallic oxide (Fe-Cu, Fe-Mn, Fe-Co) and monometallic oxide (Fe, Cu, Mn,Co) catalysts supported on silica SiO2 where prepared by incipient wetness impregnation. The total metal oxide contents were kept constant. The catalysts where calcined in two different ways, in a conventional oven and in a microwave. These catalysts were characterized with XRD, XPS and CV and were tested for the degradation of methylene blue dye at 27°C. The catalysts calcined in a microwave oven had a higher catalytic activity than those prepared in a conventional oven. The bimetallic oxide catalysts outperformed the mono- metallic oxide catalysts in the degradation of methylene blue. The Fe2MnOx prepared by microwave energy were the most active catalyst yielding the highest percentage of degradation of methylene blue dye (89.6%) after 60 minutes. The relative amounts of manganese and iron oxide were varied while keeping the total metal content in the catalyst the same. The optimum ratio of Fe to Mn was 1:7.5 since it yielded the most active catalyst. A 96.6 % removal of methylene blue was achieved after 1 hour of degradation. Lastly this ratio 1Fe:7.5Mn was prepared by varying different microwave power (600, 700 and 800 W) and irradiation time (10, 20 and 30 min). The optimum microwave power and irradiation time was 800W and 10 min with the methylene blue percentage removal of 96.6 % after 1 hour of degradation.
80

Drinking water arsenic and uranium: associations with urinary biomarkers and diabetes across the United States

Spaur, Maya January 2023 (has links)
Inorganic arsenic is a potent carcinogen and toxicant associated with numerous adverse health outcomes, and is number one on the Agency for Toxic Substances and Disease Registry Substance Priority List. Uranium is also a carcinogen and nephrotoxicant, however health effects at levels experienced by general populations is unclear. Chronic exposure to inorganic arsenic (As) and uranium (U) in the United States (US) occurs from unregulated private wells and federally regulated community water systems (CWSs). Geogenic arsenic contamination typically occurs in groundwater as opposed to surface water supplies. Groundwater is a major source for many CWSs in the US. Although the US Environmental Protection Agency sets the maximum contaminant level (MCL enforceable since 2006: 10 µg/L) for arsenic in CWSs, private wells are not federally regulated. The contribution of drinking water from private wells and regulated CWSs to total inorganic arsenic and uranium exposure is not clear.In the United States (US), type 2 diabetes (T2D) affects approximately 37.3 million people (11.3% of the population), with the highest burden in American Indian communities. Toxic metal exposures have been identified as risk factors of T2D. Most studies rely on biomarkers, which could be affected by early disease processes. Studies directly measuring metals in drinking water in US populations have been limited. In Chapter 2, we evaluated county-level associations between modeled values of the probability of private well arsenic exceeding 10 µg/L and CWS arsenic concentrations for 2,231 counties in the conterminous US, using time invariant private well arsenic estimates and CWS arsenic estimates for two time periods. Nationwide, county-level CWS arsenic concentrations increased by 8.4 µg/L per 100% increase in the probability of private well arsenic exceeding 10 µg/L for 2006 – 2008 (the initial compliance monitoring period after MCL implementation), and by 7.3 µg/L for 2009 – 2011 (the second monitoring period following MCL implementation) (1.1 µg/L mean decline over time). Regional differences in this temporal decline suggest that interventions to implement the MCL were more pronounced in regions served primarily by groundwater. The strong association between private well and CWS arsenic in Rural, American Indian, and Semi Urban, Hispanic counties suggests that future research and regulatory support are needed to reduce water arsenic exposures in these vulnerable subpopulations. This comparison of arsenic exposure values from major private and public drinking water sources nationwide is critical to future assessments of drinking water arsenic exposure and health outcomes. In Chapter 3, we aimed to determine the association between drinking water arsenic estimates and urinary arsenic concentrations in the 2003-2014 National Health and Nutrition Examination Survey (NHANES). We evaluated 11,088 participants from the 2003-2014 NHANES cycles. For each participant, we assigned private well and CWS arsenic levels according to county of residence using estimates previously derived by the U.S. Environmental Protection Agency and U.S. Geological Survey. We used recalibrated urinary dimethylarsinate (rDMA) to reflect the internal dose of estimated water arsenic by applying a previously validated, residual-based method that removes the contribution of dietary arsenic sources. We compared the adjusted geometric mean ratios and corresponding percent change of urinary rDMA across tertiles of private well and CWS arsenic levels, with the lowest tertile as the reference. Comparisons were made overall and stratified by census region and race/ethnicity. Overall, the geometric mean of urinary rDMA was 2.52 (2.30, 2.77) µg/L among private well users and 2.64 (2.57, 2.72) µg/L among CWS users. Urinary rDMA was highest among participants in the West and South, and among Mexican American, Other Hispanic, and Non-Hispanic Other participants. Urinary rDMA levels were 25% (95% confidence interval (CI): 17-34%) and 20% (95% CI: 12-29%) higher comparing the highest to the lowest tertile of CWS and private well arsenic, respectively. The strongest associations between water arsenic and urinary rDMA were observed among participants in the South, West, and among Mexican American and Non-Hispanic White and Black participants. Both private wells and regulated CWSs are associated with inorganic arsenic internal dose as reflected in urine in the general U.S. population. In Chapter 4, our objective was to evaluate regional and sociodemographic inequalities in water arsenic exposure reductions associated with the US Environmental Protection Agency’s Final Arsenic Rule, which lowered the arsenic maximum contaminant level to 10 µg/L in public water systems. We analyzed 8,544 participants from the 2003-14 National Health and Nutrition Examination Survey (NHANES) reliant on community water systems (CWSs). We estimated arsenic exposure from water by recalibrating urinary dimethylarsinate (rDMA) to remove smoking and dietary contributions. We evaluated mean differences and corresponding percent reductions of urinary rDMA comparing subsequent survey cycles to 2003-04 (baseline), stratified by region, race/ethnicity, educational attainment, and tertile of CWS arsenic assigned at the county level. The overall difference (percent reduction) in urine rDMA was 0.32 µg/L (9%) among participants with the highest tertile of CWS arsenic, comparing 2013-14 to 2003-04. Declines in urinary rDMA were largest in regions with the highest water arsenic: the South [0.57 µg/L (16%)] and West [0.46 µg/L, (14%)]. Declines in urinary rDMA levels were significant and largest among Mexican American [0.99 µg/L (26%)] and Non-Hispanic White [0.25 µg/L (10%)] participants. Reductions in rDMA following the Final Arsenic Rule were highest among participants with the highest CWS arsenic concentrations, supporting legislation can benefit those who need it the most, although additional efforts are still needed to address remaining inequalities in CWS arsenic exposure. In Chapter 5, we examined the contribution of water As and U to urinary biomarkers in the Strong Heart Family Study (SHFS), a prospective study of American Indian communities, and the Multi-Ethnic Study of Atherosclerosis (MESA), a prospective study of racially/ethnically diverse urban US communities. We assigned residential zip code-level estimates in CWSs (µg/L) and private wells (90th percentile probability of As >10 µg/L) to up to 1,485 and 6,722 participants with dietary information and urinary biomarkers in the SHFS (2001-2003) and MESA (2000-2002; 2010-2011), respectively. Total inorganic As exposure was estimated as the sum of inorganic and methylated species in urine (urine As). We used linear mixed-effects models to account for participant clustering and removed the effect of dietary sources of As and U via regression adjustment. The median (interquartile range) urine As was 5.32 (3.29, 8.53) and 6.32 (3.34, 12.48) µg/L for SHFS and MESA, respectively, and urine U was 0.037 (0.014, 0.071) and 0.007 (0.003, 0.018) µg/L. In a mixed-effects meta-analysis of pooled effects across the SHFS and MESA, urine As was 11% (95% CI: 3, 20%) higher and urine U was 35% (5, 73%) higher per 2-fold higher CWS As and U, respectively. In the SHFS, CWS and private well As explained >40% of variability in urine As and CWS U explained >20% of urine U. In MESA, CWS As and U explained >50% of urine As and U. Water from public water supplies and private wells represents a major contributor to inorganic As and U exposure in diverse US populations. In Chapter 6, we examined the association of arsenic exposures in community water systems (CWS) and private wells with T2D incidence in the Strong Heart Family Study (SHFS), a prospective cohort of American Indian communities, and the Multi-Ethnic Study of Atherosclerosis (MESA), a prospective study of racially/ethnically diverse urban US communities, to evaluate direct associations between drinking water metal exposures and T2D risk. We evaluated adults in the SHFS free of T2D at baseline (2001-2003) and followed through 2010, with available private well and CWS arsenic (N=1,791) estimates assigned by residential zip code. We also evaluated adults in the MESA free of T2D at baseline (2000-2002) and followed through 2019, with available zip code level CWS arsenic (N=5,577) estimates. We used mixed effects Cox models to account for clustering by family and residential zip code, with adjustment for sex, baseline age, body mass index (BMI), smoking status, and education. T2D incidence in the SHFS was 24.4 cases per 1,000 people (mean follow-up 5.6 years) and T2D incidence in MESA was 11.2 per 1,000 people (mean follow-up 6.0 years). In a meta-analysis of pooled effects across the SHFS and MESA, the corresponding hazard ratio (95% confidence interval) per 2-fold increase in water arsenic was 1.09 (1.01, 1.16). Differences were observed by BMI category and sex; positive associations were observed among participants with BMI <25 kg/m2 and among female participants. In categorical analyses, >10% probability of private well arsenic (<10% reference) in the SHFS and >1 µg/L of CWS arsenic (<1 µg/L reference) in MESA were associated with increased diabetes risk. Low to moderate water arsenic levels in unregulated private wells and federally regulated CWSs were associated with T2D incidence in the SHFS and MESA. In supplementary analyses, we also observed that CWS uranium was associated with T2D risk among SHFS and MESA participants with BMI<25 kg/m2.

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