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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.
211

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.
212

Functionalized Nano-structured Silicas for Trace Collection from Natural Waters

Nell, Kara 21 November 2016 (has links)
Throughout this body of work, three classes of sorbent materials were created and optimized, each designed to selectively capture organics or desired metals from natural water sources. These target species included toxic heavy metals, uranium, rare earths, and simple organics, such as benzene. Each class of sorbent materials is functionalized nanostructured silicas, created by the development of several functionalization methods: utilizing thiol-ene click chemistry, aromatic interactions, and the formation of inclusion complexes. Thiol-ene click surface modification gave rise to sorbent materials with impressive affinities for both soft metals, such as gold, and harder metals, such as uranium and rare earth elements. Applications of these materials for aqueous mining of uranium and rare earth elements from various natural water sources are presented. Two classes of materials based on supramolecular functionalization methods were prepared. In the first class, aromatic interactions allowed for surface functionalization with thiol containing aryl ligands. These materials proved to have an excellent affinity for heavy metals from natural waters, and hold promise for regenerable nanostructured silica sorbents. The second class of materials utilizes the ability of β-cyclodextins to form inclusion complexes with small molecule organics, such as benzene. The formation of inclusion complexes drove both surface functionalization and the capture of small molecule organics from aqueous solutions. This work serves to inspire the development of novel functionalized nanostructured sorbents for trace collection of toxic organics from aqueous streams. These supramolecular methods for surface medication can be expanded to nanomaterials at large. This dissertation includes both previously published/unpublished and co-authored material. / 10000-01-01
213

Estudo da ocorrência de arsênio, cobre, chumbo e zinco em drenagens na área da mina Cerro Rico em Lavras do Sul – RS - Brasil

Silva, Amanda Garcia da January 2017 (has links)
Submitted by Rosimeri Vergara (rosimerivergara@unipampa.edu.br) on 2018-11-14T21:01:08Z No. of bitstreams: 1 Dissertação Amanda Garcia da Silva 2017.pdf: 3259899 bytes, checksum: 470c3b10660c990219f4d523aede3d02 (MD5) / Approved for entry into archive by Dayse Pestana (dayse.pestana@unipampa.edu.br) on 2018-11-19T16:13:59Z (GMT) No. of bitstreams: 1 Dissertação Amanda Garcia da Silva 2017.pdf: 3259899 bytes, checksum: 470c3b10660c990219f4d523aede3d02 (MD5) / Made available in DSpace on 2018-11-19T16:13:59Z (GMT). No. of bitstreams: 1 Dissertação Amanda Garcia da Silva 2017.pdf: 3259899 bytes, checksum: 470c3b10660c990219f4d523aede3d02 (MD5) Previous issue date: 2017 / A mineração é uma atividade básica da economia mundial, e em Lavras do Sul está presente desde meados do século XVIII. No entanto, as atividades de exploração e beneficiamento do ouro geraram muitos resíduos, sendo muitos deles tóxicos. Como a região foi uma área de intensa mineração e tendo em vista os riscos da contaminação de águas por metais pesados, este trabalho propõe-se a averiguar a contaminação por alguns metais que pode eventualmente afetar o bem-estar da população e a integridade do meio ambiente. Deste modo, foram realizadas análises para a determinação da presença e concentração de chumbo, cobre, zinco e arsênio devido aos efeitos tóxicos conhecidos destes metais no ambiente aquático, e sua relação direta com as atividades de mineração de ouro, nos mananciais e sedimentos na região da mina de ouro desativada Cerro Rico, para isto foi empregada a Espectrometria de Emissão Atômica com Plasma Acoplado Indutivamente (ICP OES). Além disso, foram realizados testes físicos e químicos para categorizar as águas em relação a sua qualidade. Os dados obtidos pelas análises de águas foram tratados por meio de uma simulação computacional, para reações pertinentes ao meio, com o uso do software Phreeqc. Os resultados das análises de qualidade de água indicaram que a alcalinidade total e a Demanda Bioquímica de Oxigênio (DBO) apresentam valores inadequados para a as águas doces de classe 3. Todos os resultados foram comparados aos limites estabelecidos pela FEPAM e CONAMA. Detectou-se a presença de Pb, Cu, Zn e As nas amostras de águas, representados, principalmente, pelas espécies H2AsO4-, HAsO42-, Cu2+, Cu+, CuOH+, Pb2+, PbOH+, Zn2+ e ZnOH+, as quais apresentam-se em concentrações classificadas quimicamente como subsaturadas, exceto pelo CuOH+. Contudo, apenas o cobre excedeu os limites estabelecidos pela legislação. Outrossim, as análises realizadas nas amostras de sedimentos comprovaram a presença e concentrações acima dos valores de referência adotados pela FEPAM, para o cobre, para o chumbo e para o zinco, enquanto que o arsênio não foi detectado pelo método utilizado. As maiores acumulações de metal no sedimento foram de cobre, seguidos pelo chumbo e zinco. Conclui-se que há contaminação no entorno da Mina Cerro Rico, por cobre, chumbo e zinco, e que estes estão presentes no ambiente, principalmente, aderidos aos sedimentos. / A mining is a basic activity in the world economy, and in Lavras do Sul the activity has been present since century XVIII. However, as exploration and processing of gold, generated many wastes, many of them toxic. How the region was a intense mining area for a while, the risks of contaminated the water by heavy metals, it became necessary research about that, taking into account the well-being of the population and environmental integrity. That way, were made analysis to determinate the presence and concentration of lead, copper, zinc and arsenic for the fact that’s elements are toxic in the aquatic environments, and their direct relationship with gold mining activities, in the springs and sediments in the Cerro Rico, for this was used the Inductively Coupled Plasma Atomic Emission Spectrometry (ICP OES). In addition, physical and chemical tests were performed to categorize the quality of the waters. The data obtained by the analysis are treated by a computer simulation, for relevant reactions to the environment, using the Phreeqc software. That’s results indicated that total alkalinity and a Biochemical Oxygen Demand (BOD) presented inadequate results for a water class (3) analyzed. All the results were compared to the limits established by FEPAM and CONAMA. Were detected the presence of Pb, Cu, Zn and As in the water samples, mainly represented, by species H2AsO4-, HAsO42-, Cu2+, Cu+, CuOH+, Pb2+, PbOH+, Zn2+ and ZnOH+, which present in concentrations classified chemically how subsaturated, except for CuOH+. However, only copper has exceeded the limits set by legislation. The sediment analysis showed the presence and concentrations above the reference values adopted by FEPAM, for copper, for lead and for zinc, while arsenic was not detected by the method used. The largest accumulations were of copper, followed by lead and zinc. Concludes that the verify area around the Cerro Rico’s mine is contaminated, by copper, lead and zinc, and that these are present in the environment, mostly, on the sediments.
214

Les eaux géothermiques du gisement Khankala ˸ formation, utilisation, prévisions / Geothermal waters of the Khankala deposit ˸ formation, use, forecasts

Farkhutdinov, Anvar 23 December 2016 (has links)
Récemment, une attention considérable a été accordée dans le monde à l'utilisation des sources d'énergie renouvelables. Parmi celles-ci, les eaux géothermales sont d'une grande importance en raison de la sécurité écologique et de l'efficacité économique de leur utilisation. La Russie possède un fort potentiel de ressources confirmées en eau géothermale, mais aujourd'hui, seule une faible proportion est utilisée. L'un des territoires les plus prometteurs pour les eaux géothermales est la République Tchétchène, qui se trouve à la 3ème place parmi les régions russes pour les réserves opérationnelles approuvées de gisements d'eaux géothermales, parmi lesquelles la plus importante est le gisement de Khankala.Le développement durable des ressources en eaux géothermales exige une approche intégrée. L'analyse géostatistique et l'estimation, ainsi que la modélisation mathématique, peuvent jouer un rôle important dans la résolution des problèmes d'exploitation des eaux géothermales. La carte structurale estimée de la couche la plus productive (la couche XIII) et une carte 3-D de la distribution de la température dans le gisement de Khankala ont été créées en utilisant le krigeage universel. Les résultats ont montré l'importance du facteur structuraltectonique et du mouvement des eaux souterraines dans la formation du régime de température du territoire. La modélisation de l'exploitation des gisements géothermiques de Khankala a permis de prévoirl’évolution de la température, de fournir des recommandations sur l'emplacement des puits d'injection et la distance entre les impacts à la couche productive, et d'explorer d'autres scénarios d'exploitation comme l'utilisation périodique de couches par doublets.Le développement de l'utilisation des eaux géothermales présente des avantages incontestables: respect de l'environnement et renouvelabilité. Afin de développer ce domaine en République Tchétchène, le soutien de l'Etat est nécessaire. L'absence d'un cadre législatif adapté et de systèmes spéciaux d'assurance pose des problèmes. L'utilisation des eaux géothermales des quatorze gisements explorés en République Tchétchène peut constituer une contribution significative à la production locale d'énergie et à la stabilité économique de la région, tout en apportant des avantages environnementaux par le remplacement partiel des combustibles traditionnels.Le travail présenté ici est une contribution au projet de station géothermique de Khankala qui a été lancé avec succès au début de 2016. La station géothermique de Khankala représente une nouvelle étape dans l'utilisation des eaux géothermales dans le Caucase du Nord car il s’agit du seul exemple russe de station géothermique avec une boucle fermée de puits de production et d'injection (“doublet”) et 100% de réinjection du fluide utilisé dans le réservoir. / Recently, considerable attention in the world is given to the use of renewable energy sources. Among them geothermal waters are of great importance due to ecological safety and economic efficiency of their use. Russia has confirmed high potential of geothermal water resources, but today only a small proportion is used. One of the most promising areas for geothermal waters is the Chechen Republic, which is at the 3rd place among the Russian regions for approved operational reserves of geothermal waters deposits, the largest of which is the Khankala deposit.Achievement of the sustainability in geothermal waters resource development requires an integrated approach and an important role in solving the problems of exploitation of thermal waters is played by geostatistical analysis and estimation, as well as mathematical modelling. The adjusted structural map of the most productive layer (layer XIII) and a 3-D map of temperature distribution within the Khankala deposit were created using universal kriging. Results approved the importance of the structural-tectonic factor and movement of groundwater in the formation of the temperature regime of the territory. Modelling of the Khankala geothermal waters deposit exploitation allowed to make prognosis of temperature changes, to provide recommendations on injection-production wells location and distance between down holes and to explore possible further exploitation scenarios such as periodic use of different layers by doublet systems.The development of geothermal waters use has undoubted advantages – environmental friendliness and renewability. In order to develop this domain in the Chechen Republic the state support is needed. Issues are the lack of a special legislative framework and special insurance systems. Use of geothermal waters of the 14 explored deposits in Chechen Republic can be a significant contribution to local energy production and economic stability of the region while bringing the environmental benefits of traditional fuels partial replacement.The present work was a contribution to the Khankala geothermal station project, which was successfully launched in the beginning of the 2016. The Khankala geothermal station represents a new stage in use of geothermal waters in the Northern Caucasus as it is the only Russian example of geothermal station with closed loop of production and injection wells (“doublet”) with 100% reinjection of used fluid back into reservoir.
215

Estudo do uso de lodo de estações de tratamento de água e de esgoto urbano nas propriedades químicas do solo

Laperuta Neto, Jayme [UNESP] 25 August 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-08-25Bitstream added on 2014-06-13T19:34:36Z : No. of bitstreams: 1 laperutaneto_j_me_botfca.pdf: 1510258 bytes, checksum: f88f2af3fb61d4a1517b0357317acec0 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / No ano de 2005 foi realizado, em área da Estação de tratamento de Esgoto da Fazenda Experimental Lageado, campus da Universidade Estadual Paulista - Botucatu, SP, experimento com lodos de esgoto, proveniente da própria estação do Lageado, da estação de tratamento de esgoto da SABESP, no município de Franca-SP, e com lodo do tratamento de água, proveniente da Estação de Tratamento de Água da SABESP no município de Botucatu-SP, tendo por objetivo, a avaliação dos efeitos causados pela aplicação desses resíduos em Neosolo Quartzarênico e Latossolo Vermelho Distroférrico , irrigados com água tratada fornecida pela SABESP e por água residuária da própria estação de tratamento do Lageado. As variáveis analisadas foram : pH, acidez potencial, matéria orgânica, capacidade de troca de cátions (CTC), soma de bases (SB), saturação em bases (V%), P(resina), Al3+, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn. O experimento foi constituído de tratamentos, os quais foram montados ao acaso, em esquema fatorial 3x2x3x2, sendo 3 épocas, dois tipos de solo, 3 tipos de lodo, 2 tipos de água, com 3 repetições por tratamento, resultando no total 108 amostras. Os tratamentos foram preparados em recipientes de 9,50 litros, contendo uma mistura de 70% do volume de solo e os 30 % restantes de lodo. 2 O lodo da ETE-Lageado apresentou para a maioria dos elementos estudados, teores médios maiores, que os do lodo da ETE-Franca e ETA-Botucatu que foram semelhantes. Os teores da maioria dos elementos variam com a época, para os três lodos, sendo seus comportamentos explicados por modelos polinomiais de segunda ordem na quase totalidade. Os lodos podem ser aplicados ao solo, uma vez que os níveis dos nutrientes, foram considerados de médio para alto de acordo com Raij et al. (1996), e os níveis de Cu e Zn não se apresentaram tóxicos (U.S.EPA,1996). / An experiment using sludge from Lageado sewage farm, from SABESP sewage farm in the city of Franca-SP and sludge from SABESP waterworks in the city of Botucatu-SP was carried out in Lageado Experimental Farm, campus of Universidade Estadual Paulista, Botucatu-SP in the year of 2005, with the purpose of assessing the effects caused by the application of these residues to quartzose sand and oxisol irrigated with purified water supplied by SABESP and residuary water from Lageado waterworks. The analysed variables were: pH, potencial acidity, organic matter, cation exchange capacity (CEC), base addition (BA), base saturation (V%), P(resin), Al+3, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn. The experiment consisted of treatments, which were assembled at random, in a 3x2x3x2 factorial scheme, being respectively: 3 time, 2 types of soil, 3 4 types of sludge, 2 types of water, with three repetitions for each treatment, resulting in a total of 108 samples. The treatments were prepared in 9,5 liter containers with a mixture of 70% of the soil volume and 30 % of sludge. The sludge from the Lageado sewage farm presented, for most of the analysed elements, higher average contents than the ones from Franca sewage farm and Botucatu waterworks that were both similar. The amount of most elements varies according to time for all of 3 types of sludge, their behavior being explained through second order polynomial models almost in its totality. The sludges may be used as a soil conditioner, since the levels of the nutrients were considered as average to high according to Raij et al. (1996) and Cu an Zn levels havenþt showed as being toxic (USEPA, 1996). 1 1 kKey words: sludge; soil - chemical properties, wasted waters, sanitation.
216

Interações de alguns ácidos orgânicos com minerais e um latossolo vermelho

Bassan, Cássia Fernanda Domingues [UNESP] 22 April 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-04-22Bitstream added on 2014-06-13T19:41:57Z : No. of bitstreams: 1 bassan_cfd_dr_botfca.pdf: 763512 bytes, checksum: d8464f6ac6e486c2b19bc8c3b3b6f5aa (MD5) / Universidade Estadual Paulista (UNESP) / Certain cultures present especification in the assimilation of some ions, that are or not in available ways in the soil. The minerals have fundamental paper in the presence of those elements that, a lot of times, they are together originating from of the processes of meteorization of the rocks with the decomposition of the organic matter. This work had for objective to study the extraction and/or solubilization of some present chemical elements in the studied minerals and in a red latosoil, for the action of some organic acids produced starting from the decomposition of the matter ligno-cellulousic, through the microbial action, hoping to contribute in some way in the understanding of the mechanisms of fertility of the soil and, consequently, in the mineral nutrition of plants. The used minerals were: manganite [MnO(OH)], hematite (Fe2O3), pirolusite (MnO2), caolinite [Al2Si2O5(OH)4], goethite (HFeO2), bentonite [Na3(Al,Mg)2 2(Si4O10)(OH)2.H2O] e magnetite(Fe3O4), that commonly happen in areas humid intertropicals and a red latosoil, of sandy texture that, it represents more that 20% of the area of the State of Saint Paulo. The minerals and LV were triturated and drizzled in 0,05mm mesh, separately. After having examined with relationship your structure for Difratometric of Ray-X (XRD), 1g of those minerals and LV were conditioned, separately, in glass flasks. Some samples were only treated with distilled water and other with solution 0,02 mol.L-1 of the following acids: acetic, butyric, citric, carbolic, lactic, malic, oxalic, propionic and tannic, separately, for 53 days, with weekly agitations and conditions aerobics. After the digestion of the samples, they were certain the litio concentrations, sodium, potassium, magnesium, calcium, barium, vanadium, cromium, molibdenium, manganese, iron, cobalt, nickel, copper, zinc, cadmium, mercury, boron, aluminum, silicio, tin, lead, match... (Complete abstract click electronic access below)
217

Micotoxinas estrogênicas em águas superficiais da microbacia hidrográfica do Córrego Rico (SP): desenvolvimento de método analítico verde, ocorrência e persistência ambiental / Estrogenic mycotoxins in surface waters of Rico stream micro-basin: green analytical method development, occurrence and environmental persistence

Emídio, Elissandro Soares [UNESP] 11 April 2016 (has links)
Submitted by ELISSANDRO SOARES EMÍDIO null (elissandro_se@yahoo.com.br) on 2016-05-12T21:01:18Z No. of bitstreams: 1 Tese Elissandro Soares Emidio_IQ UNESP.pdf: 4935815 bytes, checksum: 2ed4a096c784661153f0589f1feaccf4 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-16T13:18:46Z (GMT) No. of bitstreams: 1 emidio_es_dr_araiq_par.pdf: 512252 bytes, checksum: abe4aee98ccd84a2227db13788c6221b (MD5) / Made available in DSpace on 2016-05-16T13:18:46Z (GMT). No. of bitstreams: 1 emidio_es_dr_araiq_par.pdf: 512252 bytes, checksum: abe4aee98ccd84a2227db13788c6221b (MD5) Previous issue date: 2016-04-11 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Micotoxinas estrogênicas (EM) são estrógenos produzidos como metabólitos secundários de fungos. Entre as EM estão a zearalenona (ZEN) e seus metabólitos produzidos principalmente pelo fungo do gênero Fusarium que cresce em várias culturas agrícolas. A influência da exposição às EM na saúde de mamíferos /humanos, por meio dos alimentos, tem sido extensivamente estudada. Em contraste, estudos que focam nas EM em águas superficiais e seus possíveis impactos no ambiente aquático são negligenciados. O presente trabalho apresenta os desenvolvimentos mais recentes no que concerne às micotoxinas estrogênicas, em relação às metodologias analíticas utilizadas na sua determinação e avaliação do comportamento em águas superficiais. As atividades desenvolvidas foram divididas em duas etapas: (1) Estudo analítico - desenvolvimento de um método analítico verde para a determinação das micotoxinas estrogênicas empregando a microextração líquido-líquido dispersiva (DLLME) utilizando bromosolventes e líquido iônico (IL) por cromatografia líquida de alta eficiência (HPLC) com detecção por fluorescência (FLD) ou espectrometria de massas (MS); (2) Estudo ambiental - avaliação da presença dos analitos na microbacia hidrográfica do Córrego Rico com avaliação espaço-temporal e a persistência da micotoxina zearalenona em ambientes aquáticos sob irradiação solar simulada. Vários parâmetros importantes que influenciam a eficiência de extração para DLLME foram otimizados. Em condições ótimas, a recuperação de extração para ZEN e seus metabólitos para DLLME e IL-DLLME variaram de 81 a 118 % e 76 a 81 %, respectivamente; Os desvios padrão relativos (RSD) para a precisão intra-dia e inter-dia foram menores do que 13%, em DLLME, e inferior a 5,7 % (intra-dia) para IL-DLLME. Os limites de detecção do método (LOD) e quantificação (LOQ) foram de 4-20 ng L-1 e de 8-40 ng L-1 para DLLME e 0,2 ng L-1 e 0,5 ng L-1 para IL-DLLME, respectivamente. A determinação das micotoxinas estrogênicas nas amostras de água da microbacia hidrográfica do Córrego Rico alcançaram níveis de até 59,3 ng L-1 com concentração equivalente em estradiol calculada (cEEQ) entre <0,06 e 1,42 ng L-1. Essas concentrações estão relacionadas a efeitos adversos no crescimento e reprodução de algumas espécies de peixes. No estudo de fototransformação a ZEN foi degradada rapidamente em águas naturais, com meia-vida (t1/2) de 28,3 min (água estuarina) e 135,9 min (água de rio). Os resultados indicaram que, após 1 h do tempo de irradiação, o percentual de degradação da ZEN foi de 69,4% (água do rio) e 90,8% (água estuarina). Do ponto de vista ambiental, a rápida degradação observada não deve ser interpretada “a priori”, como indicativo de baixo risco ambiental do aporte de ZEN, devendo ser investigados o comportamento ambiental e toxicológico dos seus produtos de degradação, além do que há que se considerar a constante introdução, nas águas superficiais, de microcontaminantes associados ao esgoto sanitário, como a ZEN. / Estrogenic mycotoxins (EM) are estrogens produced as secondary metabolites of fungi. The well known EM are zearalenone (ZEN) and its metabolites primarily produced by the mold Fusarium growing on a variety of crops. The influence of exposure to EM on human/mammalian health via food has been extensively studied. In contrast, studies focus on EM in surface waters and their possible impacts in aquatic environment are negligible. The current work presents the most recent developments concerning estrogenic mycotoxins, in regard to the analytic methodologies utilized in their determination and the behavior assessment in surface waters. The study was developed in two steps: (1) analytical study - Green analytical method development for determination of estrogenic mycotoxin employing microextraction liquid-liquid dispersive (DLLME) using bromosolvent and ionic liquid (IL) followed by high-performance liquid chromatography (HPLC) with fluorescence detection (FLD) or mass spectrometry (MS); (2) Environmental study - evaluation of the presence of analytes in Rico stream watershed with spatial-temporal distribution and the persistence of zearalenone mycotoxin in aquatic environments by simulated sunlight. Several important parameters influencing the extraction efficiency of DLLME were optimized. Under optimal conditions, extraction recovery for ZEN and its metabolites by DLLME and IL-DLLME were within the range of 81-118 % e 76-81 % respectively; the relative standard deviations (RSDs) for intra-day and inter-day precision were lower than 13% by DLLME, and lower than 5.7 % (intra-day) by ILDLLME. The method limits of detection (LOD) and quantification (LOQ) were from 4– 20 ng L−1 and 8–40 ng L−1, for DLLME and from 0.2 ng L−1 and 0.5 ng L−1 for ILDLLME, respectively. Determination of estrogenic mycotoxins in water samples from Rico Stream watershed reached levels of up to 59.3 ng L-1 and their corresponding calculated estrogenic equivalents (cEEQ) values were <0.06 and 1.42 ng L-1. These concentrations are related to adverse effects on growth and reproduction of some fish species. In phototransformation study ZEN degraded quickly in natural waters, with half-lives (t1/2) of 28.3 min (estuarine water) and 135.9 min (river water). The results indicated that after 1 h irradiation time, the degradation percentage of ZEN were 69.4% (river water) and 90.8% (estuarine water). From an environmental point of view, the rapid degradation observed, under laboratory conditions, should not be interpreted "a priori" as indicative of low environmental risk for ZEN, should be investigated environmental behavior and toxicology of degradation products, beyond it is necessary to considering the constant introduction into surface water of microcontaminants associated with sewage, such as this mycotoxin. / CNPq: 140990/2012-7
218

VIABILIDADE TÉCNICA, ECONÔMICA E SOCIAL DO APROVEITAMENTO DAS ÁGUAS DE CHUVA E CINZAS PARA CONSUMO NÃO POTÁVEL NA CIDADE DE SANTA MARIA/RS / TECHNICAL, SOCIAL AND ECONOMICAL VIABILITY OF RAIN AND GREY WATERS OPTIMIZATION FOR NON DRINKING WATER CONSUMPTION IN SANTA MARIA,RS

Pozzebon, Pedro Henrique Bürger 01 April 2013 (has links)
The objective of this work was to study a technical, social and economical viability of the optimization for grey and rain waters for non drinkable consumption in the city of Santa Maria, RS. The volume of the rain water tank was dimensioned in 15 m³, and so, guaranteeing the water supply in 33,55%. The rain water tank mixed with grey waters was dimensioned in 2.12m³, providing 100% of demand. Rain water optimization system provides an economy of R$ 937,19/a year, and the value of its investment was estimated in R$ 8.078,34, with maintenance and operation cost of R$ 150,00/a year. Its present net value ranged from R$ 5.629,61 to R$ 7.665,49; the payback was from ten years and three months to eleven years and four months; the internal rate of return was between 7,41% and 5,97%, and the relation cost/benefit was from 1,49 to 1,66. The mixture system of rain and grey waters saves R$ 2.793,42/a year, and the investment value was estimated in R$ 25.384,33, with operation and maintenance cost of R$ 301,74/a year. Its present net value ranged from R$ 18.679,38 to R$ 24.449,23. Payback was from ten years and two months to ten years and eleven months; the internal rate of return (IRR) was between 7,51 and 6,22; and the relation cost/benefit was between 1,58 and 1,78. In relation to social viability, a survey with people from 200 homes was accomplished to verify knowledge and acceptance of those systems population. Both, rain and grey waters optimization studies have demonstrated to be technically, economically, and socially viable. / Este trabalho teve como objetivo estudar a viabilidade técnica, econômica e social do aproveitamento das águas de chuva e cinzas para consumo não potável na cidade de Santa Maria/RS. O volume do reservatório de água da chuva ficou dimensionado em 15 m³, garantindo o abastecimento de 33,55%. O reservatório de água da chuva misturado às águas cinzas foi dimensionado em 2,12 m³, atendendo a 100% da demanda. O sistema de aproveitamento de água da chuva proporciona uma economia de R$ 937,19/ano e seu valor de investimento foi estimado em R$ 8.078,34, com custo de operação e manutenção em R$ 150,00/ano. Seu valor presente líquido variou entre R$ 7.665,49 e R$ 5.629,61, o payback ou tempo de retorno de capital entre 10 anos e 3 meses e 11 anos e 4 meses, a taxa interna de retorno entre 7,41% e 5,97% e a relação benefício/custo entre 1,69 e 1,49. O sistema de mistura da água da chuva com as águas cinzas economiza R$ 2.793,42/ano e seu valor de investimento foi estimado em R$ 25.384,33, com custo de operação e manutenção em R$ 301,74/ano. Seu valor presente líquido variou entre R$ 24.449,23 e R$ 18.679,38, o payback ou tempo de retorno de capital entre 10 anos e 2 meses e 10 anos e 11 meses, a taxa interna de retorno entre 7,51% e 6,22% e a relação benefício/custo entre 1,78 e 1,58. Quanto à viabilidade social, foi realizada uma pesquisa com pessoas de 200 domicílios para verificar o conhecimento e aceitabilidade por parte da população dos sistemas. Tanto o estudo do aproveitamento das águas de chuva e cinzas demonstraram ser viáveis técnica, econômica e socialmente.
219

Determinacao das concentracoes dos isotopos naturais de Ra em amostras costeiras do litoral norte do estado de Sao Paulo

TEIXEIRA, WASHINGTON E. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:49:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:00Z (GMT). No. of bitstreams: 1 09833.pdf: 4858140 bytes, checksum: 17b4c92943b33fb9f93cde09c096d4a3 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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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

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