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

Fitorremediação de solos contaminados com óleos lubrificantes usados / Phytoremediation of soils contaminated with used lubrificant oils

Andressa Moreira de Souza 17 July 2009 (has links)
No Brasil, a logística de recolhimento de óleo lubrificante usado é regulamentada pela Agência Nacional de Petróleo (ANP). Contudo, há riscos de contaminação ambiental durante o transporte, armazenamento, reciclagem e disposição final desse resíduo. O presente estudo teve como objetivo verificar se a capacidade de fitoextração e acumulação de metais presentes em solos contaminados com óleo lubrificante usado pode ser avaliada em fase ainda inicial do desenvolvimento de plântulas, como método de screening para futuros estudos de fitorremediação. Foram estudadas espécies com potencial fitorremediador e tolerantes à presença de petróleo no solo segundo estudos anteriores do grupo de pesquisa BioProcess girassol, soja, acácia e mamona - além de amendoim e nabo forrageiro. O girassol obteve um desempenho de remoção aparentemente superior para maioria dos metais analisados, como previsto na literatura. O nabo forrageiro, da mesma forma que na germinação, obteve resultados superiores na remoção de metais, comparado ao amendoim. A acácia, sendo uma espécie de desenvolvimento lento, produziu pouca biomassa no período inicial de crescimento, o que dificultou a quantificação de metais. Somente a biomassa produzida em meio com 0,5% de óleo foi utilizada. O girassol e o nabo forrageiro mostraram-se tolerantes à presença de óleo lubrificante usado e apresentaram as melhores taxas de remoção de metais em concentrações de 4 à 8% na fase inicial do crescimento vegetal, o que sugere tratar-se de espécies com grande potencial para fitorremediação de áreas multi-contaminadas. / In Brazil, the logistics of collecting used lubricant oil is regulated by the National Petroleum Agency (ANP). However, there is risk of environmental contamination during transport, storage, recycling and final disposal of waste. This study aimed to verify if the capacity for phytoextraction and accumulation of metals in soils contaminated with used lubricant oil can be evaluated in early stage of development of seedlings, as a method of screening for future studies of phytoremediation. Were studied species with potential phytoremediator and tolerant of the presence of oil in previous studies the second floor of the research group Bioprocess - sunflower, soybean, castor bean and acacia - in addition to peanuts and forage turnip. The sunflower had an apparently superior performance of removal for most of the metals tested, as provided in the literature. The turnip forage, the same way that the germination, obtained better results in the removal of metals, compared to peanuts. The acacia, a kind of slow development, produced little biomass in the initial period of growth, which hindered the quantification of metals. Only the biomass produced in medium with 0.5% oil was used. The sunflower and turnip forage appeared to be tolerant of the presence of used lubricant oil and showed the best removal rates of metals in concentrations of 4 to 8% in the early stages of plant growth, which suggests it is of species with great potential for phytoremediation of multi-contaminated areas.
22

Atividade mutagênica em bacia hidrográfica influenciada por sítio de contaminação de solos

Costa, Thatiana Cappi da January 2010 (has links)
A região objeto do presente estudo compreende uma área localizada às margens do rio Taquari, no município de Triunfo (RS), que pertence à bacia hidrográfica Taquari – Antas, com contaminação de solo específica por preservantes de madeira, cujo passivo ambiental são pentaclorofenol, creosoto e hidrosal arseniato de cobre cromado. O local é percorrido por corpos d’água associados à drenagem principal, formando sub-bacias. Através dos ensaios de microssuspensão com Salmonella/microssoma e Allium cepa, o trabalho teve por objetivo relacionar a atividade genotóxica com rotas de dispersão de poluentes. Analisando a área do sítio contaminado a partir dos extratos orgânicos do material drenado para o corpo d’água, após eventos de chuvas significantes e análises de extrato orgânico, água intersticial e sedimento bruto do rio. No teste Salmonella/microssoma, diversas linhagens permitiram avaliar diferentes danos ao DNA, como deslocamento no quadro de leitura (TA97a e TA98) e substituição de pares de base (TA100) em ausência (-S9) e presença (+S9) de ativação metabólica. No teste de Allium, foi possível verificar alterações em nível cromossômico. Respostas positivas de mutagenicidade pelo teste de Salmonella/microssoma do material exportado para fora da área do sítio indicam que este material pode estar sendo carreado para o rio Taquari. Isto pode ser evidenciado pela atividade mutagênica detectada em ambos os testes, na amostra de sedimento do rio coletada em frente ao sítio contaminado. O ponto a jusante no rio em relação ao ponto em frente ao sítio contaminado também foi avaliado e atividade mutagênica foi detectada, já o ponto de referência a montante mostrou pequena atividade mutagênica proveniente de fonte de contaminação diferente. Entretanto, tais poluentes não foram detectados no ponto abaixo. Os bioensaios empregados puderam indicar um possível risco de contaminação para o rio Taquari e mostraram ser eficientes para avaliar a mutagenicidade no material drenado do solo e no sedimento do rio. Embora a atividade mutagênica possa ser relacionada em parte à presença de hidrocarbonetos policíclicos aromáticos nos extratos orgânicos das amostras, derivados do preservante de madeira creosoto ou de fontes antrópicas diversas, outros compostos orgânicos podem ser encontrados nos extratos, uma vez que resíduos de pentaclorofenol estão presentes no sítio. Além disso, a complexidade das amostras de sedimento do rio poderia ainda sofrer a influência de traços de metais pesados. / Mutagenic activity, using Salmonella/microsome and Allium cepa bioassay, was employed as markers to detect pollutant dispersion routes in contaminated soil site covered by water bodies associated with the drainage toward the river. The site of the present study comprises an area located along the banks of the Taquari River, in the city Triunfo (RS) belonging to the Taquari - Antas river basin with identified environmental contaminants (pentachlorophenol, creosote and hydrosalt CCA). The Salmonella/microsoma test evaluated organic extracts of the material drained into the water body after significant rain events as well as Taquari River samples including organic sediment extract, interstitial water and gross sediment. In the Salmonella/microsome test, different strains enabled evaluation of different DNA mutations including frameshift (TA97a and TA98) and base pair substitution (TA100) in the absence (- S9) and presence (+S9) of metabolic activation. The Allium test allowed verification of chromosomal alterations. Positive mutagenicity results in the Salmonella/microsome assay of material from the area indicate that contaminant mixtures may have drained into the Taquari River, as indicated by mutagenic activity detected in both bioassays in sediment samples collected at the contaminated site. Mutagenic activity was also detected at a site downstream from the contaminated site. Although the reference area upstream showed low mutagenic activity originating from a different pollutant source, such pollutants were not found at the downstream sites. The bioassays employed, mainly the Salmonella/microsome assay, can indicate a possible contamination route toward the Taquari River and were proven efficient at evaluating the mutagenicity of drained soil material and sediment from the river.
23

Atividade mutagênica em bacia hidrográfica influenciada por sítio de contaminação de solos

Costa, Thatiana Cappi da January 2010 (has links)
A região objeto do presente estudo compreende uma área localizada às margens do rio Taquari, no município de Triunfo (RS), que pertence à bacia hidrográfica Taquari – Antas, com contaminação de solo específica por preservantes de madeira, cujo passivo ambiental são pentaclorofenol, creosoto e hidrosal arseniato de cobre cromado. O local é percorrido por corpos d’água associados à drenagem principal, formando sub-bacias. Através dos ensaios de microssuspensão com Salmonella/microssoma e Allium cepa, o trabalho teve por objetivo relacionar a atividade genotóxica com rotas de dispersão de poluentes. Analisando a área do sítio contaminado a partir dos extratos orgânicos do material drenado para o corpo d’água, após eventos de chuvas significantes e análises de extrato orgânico, água intersticial e sedimento bruto do rio. No teste Salmonella/microssoma, diversas linhagens permitiram avaliar diferentes danos ao DNA, como deslocamento no quadro de leitura (TA97a e TA98) e substituição de pares de base (TA100) em ausência (-S9) e presença (+S9) de ativação metabólica. No teste de Allium, foi possível verificar alterações em nível cromossômico. Respostas positivas de mutagenicidade pelo teste de Salmonella/microssoma do material exportado para fora da área do sítio indicam que este material pode estar sendo carreado para o rio Taquari. Isto pode ser evidenciado pela atividade mutagênica detectada em ambos os testes, na amostra de sedimento do rio coletada em frente ao sítio contaminado. O ponto a jusante no rio em relação ao ponto em frente ao sítio contaminado também foi avaliado e atividade mutagênica foi detectada, já o ponto de referência a montante mostrou pequena atividade mutagênica proveniente de fonte de contaminação diferente. Entretanto, tais poluentes não foram detectados no ponto abaixo. Os bioensaios empregados puderam indicar um possível risco de contaminação para o rio Taquari e mostraram ser eficientes para avaliar a mutagenicidade no material drenado do solo e no sedimento do rio. Embora a atividade mutagênica possa ser relacionada em parte à presença de hidrocarbonetos policíclicos aromáticos nos extratos orgânicos das amostras, derivados do preservante de madeira creosoto ou de fontes antrópicas diversas, outros compostos orgânicos podem ser encontrados nos extratos, uma vez que resíduos de pentaclorofenol estão presentes no sítio. Além disso, a complexidade das amostras de sedimento do rio poderia ainda sofrer a influência de traços de metais pesados. / Mutagenic activity, using Salmonella/microsome and Allium cepa bioassay, was employed as markers to detect pollutant dispersion routes in contaminated soil site covered by water bodies associated with the drainage toward the river. The site of the present study comprises an area located along the banks of the Taquari River, in the city Triunfo (RS) belonging to the Taquari - Antas river basin with identified environmental contaminants (pentachlorophenol, creosote and hydrosalt CCA). The Salmonella/microsoma test evaluated organic extracts of the material drained into the water body after significant rain events as well as Taquari River samples including organic sediment extract, interstitial water and gross sediment. In the Salmonella/microsome test, different strains enabled evaluation of different DNA mutations including frameshift (TA97a and TA98) and base pair substitution (TA100) in the absence (- S9) and presence (+S9) of metabolic activation. The Allium test allowed verification of chromosomal alterations. Positive mutagenicity results in the Salmonella/microsome assay of material from the area indicate that contaminant mixtures may have drained into the Taquari River, as indicated by mutagenic activity detected in both bioassays in sediment samples collected at the contaminated site. Mutagenic activity was also detected at a site downstream from the contaminated site. Although the reference area upstream showed low mutagenic activity originating from a different pollutant source, such pollutants were not found at the downstream sites. The bioassays employed, mainly the Salmonella/microsome assay, can indicate a possible contamination route toward the Taquari River and were proven efficient at evaluating the mutagenicity of drained soil material and sediment from the river.
24

Fitorremediação de solos contaminados com óleos lubrificantes usados / Phytoremediation of soils contaminated with used lubrificant oils

Andressa Moreira de Souza 17 July 2009 (has links)
No Brasil, a logística de recolhimento de óleo lubrificante usado é regulamentada pela Agência Nacional de Petróleo (ANP). Contudo, há riscos de contaminação ambiental durante o transporte, armazenamento, reciclagem e disposição final desse resíduo. O presente estudo teve como objetivo verificar se a capacidade de fitoextração e acumulação de metais presentes em solos contaminados com óleo lubrificante usado pode ser avaliada em fase ainda inicial do desenvolvimento de plântulas, como método de screening para futuros estudos de fitorremediação. Foram estudadas espécies com potencial fitorremediador e tolerantes à presença de petróleo no solo segundo estudos anteriores do grupo de pesquisa BioProcess girassol, soja, acácia e mamona - além de amendoim e nabo forrageiro. O girassol obteve um desempenho de remoção aparentemente superior para maioria dos metais analisados, como previsto na literatura. O nabo forrageiro, da mesma forma que na germinação, obteve resultados superiores na remoção de metais, comparado ao amendoim. A acácia, sendo uma espécie de desenvolvimento lento, produziu pouca biomassa no período inicial de crescimento, o que dificultou a quantificação de metais. Somente a biomassa produzida em meio com 0,5% de óleo foi utilizada. O girassol e o nabo forrageiro mostraram-se tolerantes à presença de óleo lubrificante usado e apresentaram as melhores taxas de remoção de metais em concentrações de 4 à 8% na fase inicial do crescimento vegetal, o que sugere tratar-se de espécies com grande potencial para fitorremediação de áreas multi-contaminadas. / In Brazil, the logistics of collecting used lubricant oil is regulated by the National Petroleum Agency (ANP). However, there is risk of environmental contamination during transport, storage, recycling and final disposal of waste. This study aimed to verify if the capacity for phytoextraction and accumulation of metals in soils contaminated with used lubricant oil can be evaluated in early stage of development of seedlings, as a method of screening for future studies of phytoremediation. Were studied species with potential phytoremediator and tolerant of the presence of oil in previous studies the second floor of the research group Bioprocess - sunflower, soybean, castor bean and acacia - in addition to peanuts and forage turnip. The sunflower had an apparently superior performance of removal for most of the metals tested, as provided in the literature. The turnip forage, the same way that the germination, obtained better results in the removal of metals, compared to peanuts. The acacia, a kind of slow development, produced little biomass in the initial period of growth, which hindered the quantification of metals. Only the biomass produced in medium with 0.5% oil was used. The sunflower and turnip forage appeared to be tolerant of the presence of used lubricant oil and showed the best removal rates of metals in concentrations of 4 to 8% in the early stages of plant growth, which suggests it is of species with great potential for phytoremediation of multi-contaminated areas.
25

Denaturing gradient gel electrophoresis characterisation of microbial communities in polycyclic aromatic hydrocarbon and polychlorinated biphenyl contaminated soil

Surridge, Angela Karen Joanna 28 May 2007 (has links)
Fossil fuels are currently the primary industrial energy source on Earth. They are principally composed of complex hydrocarbons in either long-chain or cyclic conformation. Industrial use of petroleum, diesel, oil, tar and other coal-derived products inevitably leads to pollution of the environment. The most serious pollution is caused by polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) that are not easily removed from soil after a spill. Long-chain and cyclic conformation makes fossil fuel hydrocarbons difficult to break down. However, certain free-living soil microorganisms have adapted to utilising these PAHs/PCBs as a source of energy. In many cases, their efficacy is greatly enhanced by the presence of plants. By inhabiting the rhizosphere, microbes form a mutualistic relationship with the plant, receiving nutrients from it and in return providing a less polluted environment in which the plant can grow. The purpose of this study was to elucidate some of the microbial population diversity in PAH/PCB-polluted soils in South Africa through the use of denaturing gradient gel electrophoresis (DGGE). In an initial study, DGGE was employed to separate soil communities in polluted and unpolluted soils into a genetic fingerprint, the main bands of which were sequenced and subjected to a BLAST analysis through a database for possible identification of species present. Phylogenetic and distance studies indicated that unpolluted soils have a far greater species diversity. It thus was evident that PAH/PCB pollution of soil leads to a decrease in microbial diversity by selecting for microorganisms with the ability to activate metabolic pathways allowing them to utilise the pollutants as an alternative source of carbon. Population diversity of pro- and eukaryotes found within polluted and non-polluted soils was compared. DGGE was employed to determine the genetic fingerprint of each population. Following this, dendogram analyses based on Shannon indices were done to determine PAH breakdown potential of prokaryotic vs. eukaryotic communities. A higher diversity and better adaptation potential were evident within prokaryotic than eukaryotic communities in pollution-stressed environments, indicating that the prokaryotic component of these samples had the greatest PAH-metabolism potential. To determine the capacity for PAH/PCB metabolism by the organisms within the soil samples being studied, the presence of xylE and ndoB genes, responsible for toluene/xylene and naphthalene biodegradation, respectively, was determined. DGGE was performed to analyse genetic diversity between these two genes, based on community fingerprints. Polluted soil communities tended to have comparable community diversity within their functional genes, depending on their physical situation, plant species proximity and soil conditions. In general, soil contained indigenous microbes with a high natural potential for biodegradation of PAHs/PCBs. A portion of the 16S gene of eight bacterial isolates representing the most dominant culturable taxa in the polluted soils was sequenced and analysed for identification purposes. These identifications were conducted in conjunction with the use of the catabolic gene probes xylE and ndoB to establish the hydrocarbon degrading capacity of the isolates. Pseudomonas, from the rhizosphere of Cyperus esculentus, was the most common PAH-degrading genus found in this study. Considering the well-established rhizosphere competence and PAH-degrading capacity of Pseudomonas, this genus seems to be the best suited for bioaugmentation purposes in South Africa. The presence of the nifH gene, the general marker gene of nitrogen-fixing bacteria in communities from unpolluted and polluted soils, was determined. It was hypothesised that bioremediation could be enhanced by nitrogen addition to polluted environments. Nested-PCR of the nifH gene was conducted on a diagnostic basis and was followed by DGGE of the product to determine the functional gene diversity within pollution-dwelling, nitrogen-fixing bacterial communities. Nitrogen-fixing microorganisms were present in all the soils sampled but, in only 80% of the pure cultures isolated from polluted and unpolluted soils and rhizospheres. Although different rhizospheres and pollutants were examined, it was found that of the polluted soils studied, most nifH gene diversity of polluted soils existed within machinery oil polluted, wood chip mulched, non-rhizosphere soil. Thus, it would appear that the more polluted the soil the higher the free microbe nitrogen fixation diversity possibly due to environmental stress. / Thesis (PhD (Microbiology))--University of Pretoria, 2007. / Microbiology and Plant Pathology / unrestricted
26

In Situ Degradation of M-Cresol in Creosote Contaminated Soil

Evanshen, Brian G., Knight, C., Zaslow, A., Scheuerman, Phillip R., Lanza, G. R. 01 January 1992 (has links)
No description available.
27

In Situ Bioremediation Potential at Cresote Contaminated Sites

Lanza, G. R., Scheuerman, Phillip R. 21 June 1992 (has links)
No description available.
28

Stabilisation of arsenic in contaminated soil using iron distributed by electricity

Engström, Kajsa January 2021 (has links)
In Boden, northern part of Sweden, there is a site called Solgårdarna which has been used for wood impregnation. The activities on the site have led to soil contamination with chrome (Cr), copper (Cu) and arsenic (As), where the arsenic contamination is the most problematic. This master’s thesis has studied the possibility to stabilise As in-situ with iron (Fe). The aim of the thesis was to investigate how well the distribution of Fe in the soil with the help of electrokinetics occurs. The work was divided into 3 parts, where part 1 and part 2 were performed in the laboratory and part 3 was performed in field. Part 1 investigated how Fe can distribute depending on how the electrodes were connected. This was done using quartz sand so visual assessment of the distribution could be done. Part 2 used the results from part 1 for a similar experiment performed on soil from Solgårdarna to see how stabilisation of As in the soil will work. Part 3 was a field test at Solgårdarna where it was tested on a pilot scale. Part 1 of was performed in two sets, 7 days each. It showed that it is possible to spread iron in the sand with the help of this method. The sand experiments achieved a covering area of 27 % respectively 28 % of rust over the entire profile during one week. Measurement with the XRF showed that where the electrode had been located the concentration of Fe increased up to 0.21-0.29 % and the concentration of Fe between the electrodes were 0.04-0.06 %. Part 2 of the experiment was performed in one setup over a 51-day period, after day 35 the experimental setup was changed due to highly fluctuating pH. The results from the experiment with soil showed that the pH is highly affected by how long the electrodes close to the sampling points were anodes or cathodes. During the experiment, a general trend for increasing As concentration in the different locations in the cell were seen. After the experiment the leachable amounts of As decreased down to 0.8-1.7 mg/kg TS compared to the untreated soil, 2.9 mg/kg TS. Part 3 of the experiment represent a 2-month field pilot test period during the autumn. Towards the end of the sampling period there was a general decrease in dissolved As and Fe in the groundwater, during the same time the groundwater level decreased, the redox potential increased and the electrical conductivity decreased. The laboratory experiments with the sand showed a removal rate around 90 % or higher, which is a good result. Those experiments were however performed using a clean inert material which is not comparable with real conditions. The field experiment was done over a short period of time due to time limitations of this thesis, while follow up of the pilot test was done within the scope of a continued research project at LTU. The given results showed a decrease in dissolved arsenic in groundwater which is a positive result. To determine whether the decrease is due to the natural adsorption of As to soil or due to the impact of provided Fe oxides requires longer monitoring of the experiment.
29

Grundwasser - Altlasten - Boden aktuell

Sohr, Antje, Gruhne, Sabine, Lausch, Christina, Barth, Natalja, Kardel, Kati, Siemer, Bernd, Ihling, Heiko, Forberg, Holger, Rank, Günter, Börke, Peter, Nowak, Erik, Becker, Jan, Willscher, Sabine, Knippert, Doreen, Kühn, Denise, Knöller, Kay, Jeschke, Christina 17 January 2013 (has links)
Zehn Fachbeiträge dokumentieren die Ergebnisse der aktuellen Projekt- und Forschungsarbeit des Landesamtes in den Themenbereichen Grundwasser, Altlasten und Boden.
30

Utilization of Geogenic Contaminated Soil in Embankments with Water Interception Approaches / 自然由来重金属等含有土の盛土材への活用に向けた降雨浸透抑制方策に関する研究

FEYZULLAH, GULSEN 25 May 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第22678号 / 地環博第199号 / 新制||地環||39(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)教授 勝見 武, 教授 三村 衛, 准教授 高井 敦史 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM

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