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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.
11

Analise de aguas de superficie e sedimentos de rios da regiao de Ipero, SP, por espectrometria de absorcao atomica e por ativacao neutronica

ARINE, DJAIR R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:29Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:55Z (GMT). No. of bitstreams: 1 07067.pdf: 10073605 bytes, checksum: ca8a78a55e7fe440b75a43fc8c0a1340 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
12

Avaliacao de metais e elementos - traco em aguas e sedimentos das bacias hidrograficas dos rios Mogi - Guacu e Pardo, Sao Paulo

LEMES, MARCOS J. de L. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:36Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:37Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
13

Avaliacao do impacto da atividade agropecuaria na qualidade da agua em areas de captacao superficial nas bacias hidrograficas dos rios Mogi - Guacu e Pardo, Sao Paulo

KATSUOKA, LIDIA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:40Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:38Z (GMT). No. of bitstreams: 1 07151.pdf: 11938144 bytes, checksum: de903224eb01dd0d5107eead6b34468a (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
14

Testing the efficacy of mitigation measures for reducing fine sediment and associated pollutant delivery to and through rivers in agricultural catchments of England

Biddulph, Matilda January 2016 (has links)
Agricultural intensification has contributed to the degradation of freshwaters in the UK, through enhanced delivery of fine sediment and associated contaminants, leading to sedimentation and eutrophication. European legislation (Water Framework Directive 2000/60/EC) and subsequent UK government initiatives such as Catchment Sensitive Farming (CSF) and Demonstration Test Catchments (DTC), aim to improve the quality of freshwaters. The DTC programme aims to find cost-effective ways to reduce agricultural diffuse water pollution. This study aimed to monitor rivers in the Hampshire Avon DTC with existing and planned mitigation measures, to measure the effectiveness of the mitigation measures, and to develop an experimental design for wider application for pollution mitigation. The methods used and tested in this study were a combination of affordable, replicable and sustainable methods (in-stream sediment collection and water quality monitoring), more complicated, expensive, analytical laboratory methods (particle size, loss-on-ignition, geochemistry, mineral magnetism, environmental radionuclides), and sediment source fingerprinting. The mitigation measures were: improvement to farm infrastructure, a wooded and a grassed riparian buffer, and a constructed wetland and in-stream pond treatment train. The improved farm infrastructure (resurfacing of a farm track, installation of a retention pond, improvements to a drainage ditch) effectively reduced inputs of sediment and associated contaminants to the river, however, this had little positive impact on the river due to greater importance of inputs from other sources. The riparian buffers were reducing fine sediment and associated contaminant inputs laterally and from upstream, however, the effectiveness of the riparian buffers was undermined by a lack of riparian buffers upstream and by sub-surface field drains. Combined analysis of the river from the farm infrastructure in the headwaters (farm scale) to the wooded riparian buffer downstream (sub-catchment scale) showed a change in the dominant source of sediment. This highlighted that an experimental design would require monitoring at varying spatial scales, as individual farm scale mitigation measures may have little impact on an entire sub-catchment due to the importance of other sources from a larger drainage area. The constructed wetland and instream pond were not effective at reducing longitudinal delivery of fine sediment and associated contaminants due to issues related to maintenance and design, emphasising the importance of appropriate targeting, design, and maintenance of mitigation measures. The results from this study showed that the methods used would be suitable as part of an experimental design for wider application. Although complex and expensive, sediment source fingerprinting is essential for determining appropriate and cost-effective mitigation at farm and sub-catchment scales. Monitoring of the sediment and water quality using the affordable, replicable and sustainable methods could be managed by farmers and landowners across a dense spatial area, at a high temporal frequency, to ensure sustainable effectiveness of mitigation. There is a need for more co-working between policy makers and scientists to ensure appropriate funding and timescales for research are provided, and with farmers and landowners to improve understanding and vested interest in the contribution of agriculture to the degradation of water quality.
15

Avaliacao do impacto de agrotoxicos em areas de protecao ambiental, pertencentes a bacia hidrografica do rio Ribeira de Iguape, Sao Paulo. Uma contribuicao a analise critica da legislacao sobre o padrao de potabilidade

MARQUES, MARIA N. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:22Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:34Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP
16

Analýza časových řad koncentrací aniontů a kationtů na povodí Kopaninského toku ve vazbě na využití půdy. / Analysis of time series of anions and cations concentrations in the Kopaninsky stream catchment in relation to land use.

KOUŘIMSKÁ, Kateřina January 2008 (has links)
Water quality of small streams in agricultural landscape is mostly classified as polluted or very polluted. The reason of enhanced mineralization of organic mass in soil can be found in changed physical, chemical and biochemical properties of soil profile, which negatively display in mineralization of organic mass and nitrogen release to soil water. Analysis of water quality in agricultural river-basin prove that quality of surface water in areas with high nitrate loadings did not significantly improve in recent years. Nitrates in water are a distinct anthropogenic factor, which defines well disturbance in natural environment. This thesis deals with analysis of time series of nitrate concentrations in the Kopaninsky stream catchment in Bohemo-Moravian Highland. Further the progress in nitrate concentration and its seasonal component is researched.
17

Medida da umidade do solo com sonda de neutrons

FALLEIROS, MARCOS de C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:37:48Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:12Z (GMT). No. of bitstreams: 1 05379.pdf: 4344136 bytes, checksum: b82d5226e24d569d19317b8dc8a173fd (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
18

Desenvolvimento e validacao de metodologia analitica para determinacao de hidrocarbonetos policiclicos aromaticos (HPAS) em sedimentos. Avaliacao da represa do Parque Pedroso, Santo Andre, SP / Development and validation of analytical methodology for determination of polycyclic aromatic hydrocarbons (PAHS) in sediments. Assessment of Pedroso Park dam, Santo Andre, SP

BRITO, CARLOS F. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:05Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:15Z (GMT). No. of bitstreams: 0 / Os hidrocarbonetos policíclicos aromáticos (HPAs) por serem considerados contaminantes persistentes, pela sua ubiqüidade no meio ambiente e pelo reconhecimento de sua genotoxicidade, têm estimulado atividades de pesquisa com o objetivo de determinar e avaliar as origens, transporte, transformação, efeitos biológicos e a acumulação em compartimentos de ecossistemas aquático e terrestre. Nesta dissertação, a matriz estudada foi o sedimento coletado na represa do Parque Pedroso em Santo André, SP. A técnica analítica empregada foi a cromatografia líquida em fase reversa com detector UV/Vis. O tratamento dos dados foi estabelecido durante o processo de desenvolvimento da metodologia para que houvesse confiabilidade nos resultados. As etapas envolvidas foram avaliadas usando o conceito da Validação de Ensaios Químicos. Os parâmetros selecionados para a validação analítica foram Seletividade, Linearidade, Intervalo de Trabalho, Sensibilidade, Exatidão, Precisão, Limite de Detecção, Limite de Quantificação e Robustez. Esses parâmetros apresentaram resultados satisfatórios, o que permite a aplicação da metodologia desenvolvida, sendo ainda um método simples que permite a minimização da contaminação e da perda de compostos por excesso de manipulação. Para os HPAs estudados não foram encontrados resultados positivos, acima do limite de detecção, em nenhuma das amostras coletadas na primeira fase. Já na segunda coleta foram encontradas pequenas alterações principalmente em acenaftileno, fluoreno e benzo[a]antraceno. Embora a área se encontre preservada, já se notam pequenos sinais de contaminação. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
19

Desenvolvimento de metodologia para a determinacao de herbicidas e inseticidas em aguas superficiais utilizando extracao liquido-solido e cromatografia liquida de alta eficiencia

LEBRE, DANIEL T. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:14Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:09Z (GMT). No. of bitstreams: 1 06866.pdf: 7359127 bytes, checksum: 1cbe4a8ebc4462e23ff8a89a820eddab (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
20

Analise de aguas de superficie e sedimentos de rios da regiao de Ipero, SP, por espectrometria de absorcao atomica e por ativacao neutronica

ARINE, DJAIR R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:29Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:56:55Z (GMT). No. of bitstreams: 1 07067.pdf: 10073605 bytes, checksum: ca8a78a55e7fe440b75a43fc8c0a1340 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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