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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.
81

Contaminação de solo por metais tóxicos provenientes do desgaste inadequado de pilhas zinco-carbono de uso doméstico

GAZANO, VANESSA S.O. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:51:32Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:56Z (GMT). No. of bitstreams: 0 / O presente trabalho determinou a concentração dos metais zinco, manganês, cádmio, chumbo, níquel, cobre e cromo no efluente e solo de quatro colunas de latossolo indeformadas. Duas colunas foram contaminadas por pilhas do tipo zinco-carbono e duas colunas foram utilizadas como referência, além de pilhas isoladas, foram todas lixiviadas por uma solução \"água de chuva\" (HNO3 + H2SO4, pH 4,0). Os metais no efluente e no solo foram determinados pela técnica de ICP-OES. A avaliação do efluente e do solo das colunas contaminadas pelas pilhas mostrou um incremento das concentrações dos metais, principalmente de zinco, manganês e chumbo. A sequência das massas acumuladas dos metais no efluente e no solo da coluna contaminada apresentaram uma sequência semelhante a da lixiviação isolada da pilha (Zn > Mn > Pb > Cr > Cu > Ni > Cd), confirmando a influência da pilha nas concentrações dos metais no efluente e solo das colunas. Observou-se também que a contaminação de Zn e Mn tende a migrar da camada superior da coluna de solo para as camadas inferiores. O estudo mostrou que as pilhas podem causar uma contaminação significativa do solo para os metais Zn, Mn e Pb e possivelmente também para Cd. Esta contaminação do solo poderia vir a causar uma contaminação da água subterrânea para os metais Zn, Mn e Pb, dependo das características do perfil do solo. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
82

Estudo da variação sazonal das concentrações de sup(222)Rn em amostras de água do mar nas enseadas de Ubatuba, para a estimativa da descarga de águas subterrâneas

LOPES, PATRICIA da C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:51:00Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:21Z (GMT). No. of bitstreams: 1 10498.pdf: 6854267 bytes, checksum: 0e919f3b8c415c7b067a987074165112 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP / FAPESP:02/08902-9
83

Caracterização química de hormônios sexuais em águas de poço da região da USP via cromatografia a gás acoplada a espectrometria de massas CG/EM / Chemical characterization of sex hormones in water from wells in the region of the USP by gas chromatography coupled to mass spectrometry GC/MS

GONSCHOROWSKI, GRACIELE P. da C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:41:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:40Z (GMT). No. of bitstreams: 0 / As substâncias farmacologicamente ativas tem despertado interesse da comunidade científica nos últimos anos. Estas substâncias são usadas em medicina diagnóstica, tratamento e prevenção de doenças. Algumas destas substâncias são excretadas na forma não metabolizada e outras na forma ativa, sendo que muitas delas não são completamente removidas nas estações de tratamento de esgotos. Um desses grupos ativos de substâncias, são os estrogênios esteróides e seus conjugados, os quais tem sido identificados como grandes contribuintes para a desregulação endócrina. O presente trabalho consistiu de desenvolver um método analítico empregando extração em fase sólida (SPE), usando cartuchos Strata-X, e cromatografia a gás acoplada a espectrometria de massas (CG/EM) para a determinação dos hormônios sexuais contidos nas águas subterrâneas da regiâo da cidade universitária de São Paulo, mais especificamente do Instituto de Pesquisas Energéticas e Nucleares (IPEN). Dentre os hormônios conhecidos, foi dado destaque nesse trabalho para os estrogênios naturais estradiol, estrona e progesterona, e os estrogênios sintéticos etinilestradiol e norgestrel. A validação do método foi baseada no documento do INMETRO e da ANVISA. Os índices de recuperações estiveram entre 70-120% para todos os compostos, estando dentro da faixa recomendada pela literatura para matrizes ambientais. Os limites de detecção encontrados variaram de 0,062 a 0,498 μg:L-1, e os limites de quantificação foram de 0,942 a 1,343 μg:L-1. Todos os compostos apresentaram coeficientes de determinação superiores a 0,99. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
84

Determinacao da concentracao dos isotopos naturais de uranio e torio em amostras de agua

CAMARGO, IARA M.C. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:38:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:41Z (GMT). No. of bitstreams: 1 05677.pdf: 3521641 bytes, checksum: 4f8e0c1a38cebeb07dd9281a01683f8e (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
85

Estudo dos fluxos fluviais de isótopos naturais de rádio e bário dissolvido para as enseadas de Ubatuba, Litoral Norte do Estado de São Paulo / Fluvial fluxes of natural radium isotopes and dissolved barium for Ubatuba embayments, São Paulo

SOUSA, KEILA C.P.M. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:54:57Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:04Z (GMT). No. of bitstreams: 1 12812.pdf: 8731040 bytes, checksum: c07544bfbe9cb89c2d4ba26ddd54a72e (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
86

Calibracao de uma linha de emanacao para determinacao de sup(222) Rn em amostras de agua do mar

FARIAS, LUCIANA A. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:01Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:36Z (GMT). No. of bitstreams: 1 08290.pdf: 1216858 bytes, checksum: 06f9803f0f94d1535cd74d6f3549a749 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
87

Investigação de aquífero fraturado para entendimento de fluxo e transporte de contaminantes clorados: estudo de caso em Valinhos, SP / not available

Aline Campello Fanti 29 March 2016 (has links)
Casos de contaminação de aquíferos fraturados são bastante complexos, tendo em vista a heterogeneidade das redes de fraturas, e no geral, sua investigação demanda a utilização de técnicas pouco usuais, como por exemplo o imageamento acústico e a perfilagem de velocidade de fluxo de água. Na área de estudo, localizada em Valinhos/SP, o uso inadequado de solventes organoclorados no passado ocasionou a contaminação do aquífero raso em duas áreas, e o aparecimento de concentrações no aquifero profundo levaram a condução do atual trabalho, que teve como principal objetivo a elaboração de um modelo conceitual de fluxo de água e transporte de contaminantes no aquífero cristalino. Previamente à investigação do aquífero fraturado, foi realizada uma análise de trabalhos existentes, incluindo a interpretação de lineamentos, levantamentos geológicos além de perfilagens geofísicas de superfície. Em cada área investigada, foi realizada a perfuração de um poço profundo e aplicadas as técnicas de perfilagens de raios gama, cáliper, flowmeter, imageamento acústico, além da filmagem do poço e realização de ensaios hidráulicos nos dois pontos perfurados. Para caracterização química do aquífero fraturado, foram realizadas coletas de água subterrânea em intervalos selecionados com a utilização de obturadores pneumáticos. As cargas hidráulicas medidas durante a amostragem também auxiliaram no entendimento da direção do fluxo de água. O aquífero cristalino é formado por rochas gnáissicas e se encontra bastante fraturado e intemperizado, principalmente na porção superficial da rocha (até aproximadamente 65,0 m) onde as maiores velocidades de fluxo de água também foram observadas. A rocha sã possui uma menor densidade de fraturas e predominância de minerais mais claros. As fraturas de baixo a médio angulo de mergulho (Grupo 1) são as mais frequentes em ambas as perfurações e possuem direção principal N-S a NE-SW. São observadas, no geral, exercendo grande influência sobre o fluxo de água, principalmente na porção alterada do gnaisse. Fraturas com ângulo elevado de mergulho, classificadas como Grupo 2 (paralelas à foliação) e Grupo 3 (direção NW à W), são também observadas ao longo de toda a perfuração estabelecendo a conexão hidráulica entre as fraturas do Grupo 1. Em menor proporção, são ainda verificadas fraturas com ângulos de mergulho >40 ° pertencente aos Grupos 4 (NE-SW), 5 (E-W), 6 (NW-SE) e 7 (E-W). O fluxo de água subterrânea se mostrou descendente na porção superior da rocha alterada e ascendente na porção mais profunda, possivelmente direcionando a água subterrânea para a região de transição da rocha mais alterada para a rocha sã (entre 61 a 65 m de profundidade). Apesar do fluxo ascendente em profundidade, o bombeamento de poços tubulares existentes no entorno ao longo dos anos, favoreceu a migração dos contaminantes para porções mais profundas. Os contaminantes observados no poço tubular P6 possuem maior semelhança com os contaminantes observados na Área 2, e ambos estão localizados entre lineamentos NW-SE, indicando uma possível influência dos lineamentos no controle sobre o fluxo de água. No entanto, para entendimento do transporte dos contaminantes em área, é necessário um adensamento da rede de monitoramento, levando em consideração a heterogeneidade do meio e as incertezas relacionadas à extrapolação dos dados para áreas não investigadas. / Cases of contamination in fracture aquifers are complex, given the heterogeneity of the fractures network and the common requirement of unusual techniques for investigation, such as the acoustic imaging and water flow velocity profile. In the study area, located in Valinhos / SP, the inappropriate use of organochlorine solvents in the past caused the contamination of the shallow aquifer in two areas, and the appearance of concentrations in the deep aquifer, lead to the current work, whose main goal was the development of a conceptual model of groundwater flow and contaminants transport in the crystalline aquifer. An analysis of pre-existing works, including the interpretation of lineaments, geological surveys as well as surface geophysical profiling, was conducted previously the investigation of fractured aquifer. A deep well was drilled in each area and applied the profiling methods gamma ray, caliper, flowmeter and acoustic imaging, as well as filming the wells and conducting hydraulic tests in two drillings. For chemical characterization of the fractured aquifer, groundwater sampling were collected at selected intervals with the use of pneumatic packers. Hydraulic heads measured during sampling also helped in understanding the direction of water flow. The crystalline aquifer is consisted by a fractured and weathered gneissic rock, especially in the upper portion of the rock (up to approximately 65.0 m) where higher water flow rates were observed. The fresh rock has a lower fracture density and predominantly lighter minerals. Fractures of low to medium dip angle (Group 1) are the most frequent in both boreholes. Their main direction is N-S to NE-SW, and they are in general, exerting great influence on the water flow, especially in the weathered portion of the gneiss. Fractures with high dip angle classified as Group 2 (parallel to foliation) and Group 3 (direction NW to W) are also observed throughout the drillings, establishing the hydraulic connection between the fractures from Group 1. At a lower frequency, fractures with dip angles >40 °, classified as groups 4 (direction NE-SW), 5 (E-W), 6 (NW-SE) and 7 (E-W), are verified. The water flow was downgradient in the surficial weathered portion of the rock, and upgradient in the deepest portion, probably directing the water flow to the transition portion of altered rock for the fresh rock (between 61 to 65 m in depth). Despite the upward flow in higher depth, pumping existing wells in the vicinity over the years favored the migration of contaminants into deeper portions of que aquifer. The compounds observed in the tubular well P6 have a greater resemblance to the contaminants observed in Area 2, and both are located between NW-SE lineaments, indicating a possible influence on control over the water flow and contaminant transport. However, a dense of monitoring network is necessary to understand the transport of contaminants in the study area, for which should be considered the proposed objectives, and taken into account the heterogeneity of the environment and the uncertainties related to extrapolation of data to non-investigated areas.
88

Modeling Salinity Impact on Ground Water Irrigated Turmeric Crop

Kizza, Teddy January 2013 (has links) (PDF)
Soils in irrigated fields are impacted by irrigation water quality. Salts in the irrigation water may accumulate in the soil depending on amount of leaching, the quality of water and type of ions present. Salinity is an environmental hazard that is known to limit agriculture worldwide. The quality of irrigation water is thus of concern to agriculturists. More so is the impact it has on productivity. The objective of this study was to quantify the impact due to use of ground water of such quality, with respect to salinity, as found in Berambadi watershed of Southern India, under farmers‟ field conditions. Turmeric (Curcuma Longa L.) was used for the study, based on salt sensitivity, under furrow irrigation. Study sites were selected basing on quality of water, with respect to salinity, crop and irrigation method. Samples of both soil and water were collected from each site and analyzed in the laboratory. The samples were analysed for salinity, alkalinity, pH and Cations of Magnesium, Sodium, Calcium and potassium as well as Chlorides and Sulfates. In addition soil was analysed for texture and Organic matter content. Non destructive plant monitoring for Leaf area (Index), number of leaves and plant height was done up to 210 days from planting. Profile, up to 80 cm depth, soil moisture was monitored at six plots using TDR and surface, up to 6cm depth, soil moisture for all the plots using Theta probe. Potential yield was obtained using STICS 6.9 crop model while field yield was estimated from rhizomes average weight of three plants. For both potential and observed yield estimation, a plant density of 9 plants per M2 was used. The quality parameters in water were correlated to soil parameters and to crop growth and ultimate yield. Impact due to salinity was then identified and quantified using relative yield. Identified quality problems in terms of turmeric response were, salinity, alkalinity and pH there was significant positive correlation between irrigation water salinity and soil salinity. Some wide scatter was observed and could be indicative of irrigation management practices, soil texture difference and other local variations. Observed turmeric yield was significantly negatively correlated to soil salinity. There was a monotonically increasing gap between simulated and observed yield as salinity increased. The maximum observed yield was 71% of the potential. The highest impact due to salinity was observed at 2.1 dS/m amounting to 44 % yield reduction. Excessive chlorosis due to iron deficiency occurred at 24.5% as CaCO3 and pH 7.5. Irrigation water pH was normal as per the guidelines. Soil pH was not so varied; it ranged between 7.1-7.9 except for one site where it was 6. Within the 7.1-7.9 range there was no effect on crop and yield observed. Interaction of stress factors observed was between salinity and alkalinity. The other was rhizome rot disease. Loss of yield to salinity was significant but farmers have no specific plans to leach out salts nor do they have an idea that ground water quality can actually negatively impact productivity. Salinity in irrigation water was in the moderately saline range. While that in the soil was low to slightly saline but could increase given the management practices.
89

Hebungen der Tagesoberfläche als Folge des Grundwasserwiederanstiegs stillgelegter Braunkohlentagebaue

Lieske, Katharina, Schade, Marco 29 July 2016 (has links) (PDF)
Die Grundwasserstände unterliegen in den Gebieten des Braunkohlenbergbaus permanenter, bergbaulich bedingter Veränderung. Im Einflussbereich der aktiven Braunkohlentagebaue überwiegen sinkende - im Bereich der ehemaligen Tagebaubereiche nach Einstellung der Wasserhaltungsmaßnahmen dagegen steigende Grundwasserstände. Der Grundwasserwiederanstieg im Verantwortungsbereich der LMBV mbH ist schon weit vorangeschritten aber noch nicht überall abgeschlossen. Im Zuge der Auswertung von regelmäßig durchgeführten Präzisionsnivellements wurden in den gewachsenen Randbereichen der in Flutung befindlichen Tagebauseen Hebungen festgestellt, die in ihrer räumlichen Ausdehnung und dem Betrag mit den Ergebnissen der Beobachtungen der Grundwasserstände korrelieren. Rückblickend werden die Zusammenhänge zwischen Grundwasserwiederanstieg und Hebungen des gewachsenen Bodens anhand von Beispielen von bereits gefluteten Tagebauseen aus dem Mitteldeutschen Braunkohlenrevier betrachtet. Die festgestellten Hebungen vollziehen sich längerfristig über mehrere Jahre. Die Hebungsbeträge erreichen maximale Werte von einigen Zentimetern - erreichen aber nicht die Beträge der früheren sümpfungsbedingten Senkungen. Schädliche Auswirkungen auf Bauwerke durch grundwasserwiederanstiegsbedingte Hebungen waren nicht zu erwarten und sind auch nicht eingetreten. / Water tables in lignite mining areas are characterized by a permanent mining-related variation. In the sphere of influence of the active lignite mines preponderates decreasing – in reach of the abandoned lignite mining areas in contrast increasing water tables. The groundwater resurgence within the areas of responsibility of LMBV mbH is widely pro-ceeded but yet not completed in all areas. In the course of the evaluation of regularly conducted precision levellings uplifts were detected in the natural boundary areas of post-mining lakes still in flooding progress. These uplifts correlate in their regional/areal dimension and magnitude with the results of the water tables. The coherence between groundwater resurgence and the uplifts will be examined retrospectively based on examples of flooded post-mining lakes from the mining area around the cities of Leipzig and Halle. The observed elevation take place over some years. The elevation amount reaches maximum values of a few centimeters, but doesn’t reach the amount of the former drainage caused subsidence. Adverse effects on buildings by groundwater resurgence caused elevation were not expected and didn’t occur so far.
90

Analysis of temporal and spatial variations in water storage by means of gravimetric and hydrologic methods in the region around the South African gravimetric observation station

Mahed, Gaathier January 2013 (has links)
This work examines the use of gravity data and its application to subsurface water reservoirs in the immediate vicinity of the South African Geodynamic Observatory, Sutherland (SAGOS), situated in a semi-arid region of the Karoo region of South Africa, and underlain by the Karoo sedimentary rocks intruded by dolerite dykes and sills. SAGOS houses the only supergravity metre (SG) in Africa, and this thesis sets out to test its use in monitoring groundwater dynamics using hydrological and gravity data. The main aim of this work is the application of the SG data, in conjunction with hydrological data, to better understand episodic recharge of subsurface reservoirs. The importance of water as a resource, globally and specifically the Karoo, is reviewed in conjunction with supply and demand of water. This is to contextualise the socio-economic, technical as well as policy issues related to water resource management. Applicable technologies for water resource management and efficient water use are highlighted and the application of gravity to hydrology is introduced, including satellite as well as ground based tools. In addition, arid zone hydrology as well as recharge and its mechanisms are analysed in order to better understand these processes when examined from gravity measurements. Issues related to understanding flow within the vadose zone as well as in secondary aquifers are examined, and gravity residuals and subsurface hydrology are highlighted. Thereafter, a conceptual groundwater flow modelof the study area is developed using multiple tools. First, the geology around SAGOS was mapped using SPOT 5 imagery and then ground truthed. Second, stable isotopes and water chemistry analysis was undertaken on water samples from selected boreholes. The results allude to preferential flow acting as the main mechanism for groundwater recharge. Follow-up pump-tests illustrate that fracture connectivity is greatest at close proximity to the dyke. Soil mapping, using aerial photography was also undertaken. Duplex soils, enriched with clay at depth, dominate the study area. Using in-situ infiltration tests, it is shown that the alluvium, which lines the river beds, has a higher hydraulic conductivity than the other soils, confirming that these streams act as preferential conduits for subsurface recharge. Precipitation events were correlated against gravity residuals at 4 wells, over different time periods. The results are examined using time series analyses. Gravity residuals from well SA BK07, over a period of 24 hours after the rainfall event, delineate instances of negative correlations, as well as strong positive correlations (of up to 0.9). On the whole however, correlations between gravity and groundwater at SA BK07 are variable and weak, and in conjunction with water level measurements and water chemistry, the data suggest that this well is located in a dynamic conduit (throughflow) and not in a permanent groundwater reservoir. By contrast, other wells show strong positive correlations between gravity residuals and water levels following episodic recharge events for a later time series. Correlations between the water levels and gravity residuals in wells SA BK04, SA BK05 and SA BK 01 are in excess of 0.7 for specific rainfall events. In summary, the results suggests that gravity is an excellent tool for measuring episodic groundwater recharge within the immediate vicinity of the SAGOS. This implies that gravity can aid in monitoring groundwater losses/gains in arid and semi-arid areas. Recommendations for future work are highlighted at the end; these include the possible use of hydrological modelling of reservoirs at various scales and then comparing these results to the SG as well as GOCE and GRACE satellites data, and then improving numerical modelling of the groundwater dynamics for sites like Sutherland and the surrounding arid Karoo region, where sparse water shortages, and potential pollution related to fracking for shale-gas, are likely to compete with established water needs for farming and human consumption. It is also suggested that the gravity modelling be examined to better understand site specific scenarios and thus aid in improving the processing of the gravity signal.

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