944 resultados para Radioactive substances in soils.
Resumo:
O objetivo do presente deste trabalho foi avaliar a toxicidade aguda, crônica e a genotoxicidade sobre E. andrei causadas por solo recém-contaminado com óleo lubrificante usado e após biorremediação por diferentes estratégias, após 22 meses, e paralelamente ao estudo de ecotoxicidade, foi conduzida uma investigação comparativa de três métodos de extração de HTP e HPA de solos para análise cromatográfica. A comparação das técnicas de extração evidenciou que para HTP, a técnica de extração acelerada por solvente-ASE foi a que melhor recuperou n-alcanos; já para as frações HRP e MCNR as técnicas soxhlet e micro-ondas-MARS não apresentaram diferenças significativas e foram melhores que ASE. Para HPA, a técnica de extração por soxhlet foi a que apresentou melhor recuperação em todos os solos. O teste de mortalidade apresentou, aos 14 dias, taxas crescentes de mortalidade de 10 6%, 20 0%, 73 25%, 93 12% e 100 0% para amostras de CONT (solo controle, sem contaminação artificial), BIOS (solo contaminado com 5% de OLU e biorremediado por bioestimulo), BIOA1 (solo contaminado com 5% de OLU e biorremediado por bioestimulo + bioaumento com adição de 10% de RSU maturado), e BIOA2 (solo contaminado com 5% de OLU e biorremediado por bioestimulo + bioaumento com adição de 10% de RSU semi-maturado) e OLU (solo contaminado com 5% de OLU), respectivamente. Aos 28 dias, entretanto, BIOS e OLU apresentaram taxas de mortalidade de 97 % 6 % e de 100 % 0 % respectivamente, valores estes significativamente superiores ao CONT. Foram observadas deformações anatômicas nos indivíduos mantidos em BIOS e OLU, assim como diminuição da biomassa em todas as amostras, evidenciando efeitos crônicos. O teste de reprodução, aos 28 dias, foram observadas grandes quantidades de indivíduos jovens nos solos biorremediados e recém-contaminado. No entanto, aos 56 dias houve uma diminuição dessas formas e o controle (CONT) exibiu uma quantidade maior de formas juvenis. O teste de densidade e viabilidade celular mostrou ser indicador sensível para toxicidade crônica apresentando queda nos solos BIOS e OLU em relação ao CONT com diferenças significativas (p <0.05). Não foram observados micronúcleos nos solos em estudo. Tal observação reforça a necessidade de testes de ecotoxicidade para avaliar a real eficácia de tecnologias de tratamento.
Resumo:
O objetivo do presente deste trabalho foi avaliar a toxicidade aguda, crônica e a genotoxicidade sobre E. andrei causadas por solo recém-contaminado com óleo lubrificante usado e após biorremediação por diferentes estratégias, após 22 meses, e paralelamente ao estudo de ecotoxicidade, foi conduzida uma investigação comparativa de três métodos de extração de HTP e HPA de solos para análise cromatográfica. A comparação das técnicas de extração evidenciou que para HTP, a técnica de extração acelerada por solvente-ASE foi a que melhor recuperou n-alcanos; já para as frações HRP e MCNR as técnicas soxhlet e micro-ondas-MARS não apresentaram diferenças significativas e foram melhores que ASE. Para HPA, a técnica de extração por soxhlet foi a que apresentou melhor recuperação em todos os solos. O teste de mortalidade apresentou, aos 14 dias, taxas crescentes de mortalidade de 10 6%, 20 0%, 73 25%, 93 12% e 100 0% para amostras de CONT (solo controle, sem contaminação artificial), BIOS (solo contaminado com 5% de OLU e biorremediado por bioestimulo), BIOA1 (solo contaminado com 5% de OLU e biorremediado por bioestimulo + bioaumento com adição de 10% de RSU maturado), e BIOA2 (solo contaminado com 5% de OLU e biorremediado por bioestimulo + bioaumento com adição de 10% de RSU semi-maturado) e OLU (solo contaminado com 5% de OLU), respectivamente. Aos 28 dias, entretanto, BIOS e OLU apresentaram taxas de mortalidade de 97 % 6 % e de 100 % 0 % respectivamente, valores estes significativamente superiores ao CONT. Foram observadas deformações anatômicas nos indivíduos mantidos em BIOS e OLU, assim como diminuição da biomassa em todas as amostras, evidenciando efeitos crônicos. O teste de reprodução, aos 28 dias, foram observadas grandes quantidades de indivíduos jovens nos solos biorremediados e recém-contaminado. No entanto, aos 56 dias houve uma diminuição dessas formas e o controle (CONT) exibiu uma quantidade maior de formas juvenis. O teste de densidade e viabilidade celular mostrou ser indicador sensível para toxicidade crônica apresentando queda nos solos BIOS e OLU em relação ao CONT com diferenças significativas (p <0.05). Não foram observados micronúcleos nos solos em estudo. Tal observação reforça a necessidade de testes de ecotoxicidade para avaliar a real eficácia de tecnologias de tratamento.
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This is the report from the South and West Cumberland Fisheries Advisory Committee meeting, which was held on the 9th January, 1978. It covers information on water resource development for West Cumbria which includes details on the River Derwent and Ennerdale schemes, fisheries income and expenditure, licence duties, Eskett Quarries and radioactive discharge in relation to fishery interests. It also looks at the report by the area fisheries officer on river conditions and fishing, Holmwrangle Hatchery and stocking. Included in this report is a note on survey work carried out on Braystones Tarn, resources and the collection of fish for hatcheries. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.
Resumo:
This is the report from the Eden and District Fisheries Advisory Committee meeting, which was held on the 10th January, 1978. It covers information of fisheries income and expenditure, licence duties, regional water resources study, salmon fishing, radioactive discharge in relation to fishery interests and a brief mention about the possibilities of opening Castle Carrock reservoir for public angling. It also includes the report by the area fisheries officer on river conditions and fishing, Holmwrangle Hatchery and stocking. Included in this report is a note on the survey work carried out on the Upper Eden and Eamont regarding brown trout, the collection of fish for hatcheries, Redd counting and the transfer of coarse fish. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.
Resumo:
This is the report from the South Lancashire Fisheries Advisory Committee meeting, which was held on the 11th January, 1978. It covers information of fisheries income and expenditure, licence duties, regional water resources study, Worthington reservoirs regarding fishery regulations and radioactive discharge in relation to fishery interests. It also includes the report by the area fisheries officer on river conditions and fishing for salmon, sea trout, brown trout and coarse fish, numbers of migratory fish movements at Waddow Weir, Winckley Hall and Locks Weir, and Langcliffe Hatchery. Included in this report is also a brief note on fish disease in salmon in the Ribble and Hodder, and the improvement of Stock Beck after the pollution incident. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.
Resumo:
This is the report from the Lune, Wyre and Furness Fisheries Advisory Committee meeting, which was held on the 16th January, 1978. It covers information on fisheries income and expenditure, licence duties, regional water resources study, fish stocks in the River Leven, Skerton fishery and radioactive discharge in relation to fishery interests. It also includes investigations for future water supplies to South West Cumbria and the report by the area fisheries officer on river conditions and fishing for salmon, sea trout, and coarse fish, numbers of fish movements at Haverthwaite, Broadraine and Forge Weir fish monitoring station. Included in this report is also work at Middleton Hatchery, a brief note on fish disease in migratory fish in the Lune and Kent, and net catch figures for the year for the Rivers Lune, Kent, Leven and Duddon. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.
Resumo:
This is the report from the Mersey and Weaver Fisheries Advisory Committee meeting, which was held on the 18th January, 1978. It covers information of fisheries income and expenditure, licence duties and radioactive discharge in relation to fishery interests. It also includes the report by the area fisheries officer on river conditions and fishing, Tintwistle hatchery, and general fisheries management. Included in this report is also fish mortalities and stocking numbers of coarse fish and non-migratory trout. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.
Resumo:
Na frota automotiva nacional, veículos movidos a diesel e biodiesel são utilizados em larga e pequena escala, respectivamente, fazendo com que haja uma preocupação com os gases da exaustão provenientes destes motores. Ao ser fabricado, o veículo passa por testes rigorosos das emissões gasosas, segundo as regras do PROCONVE. Porém, estes testes regulam apenas as substâncias químicas contidas na legislação vigente, cujos riscos à saúde humana e ao meio ambiente são conhecidos. Portanto, conhecer o maior número de componentes ainda não contemplados pela legislação, em especial metais no material particulado, é de suma importância para subsidiar futuras alterações e inclusões na lista de componentes regulados. De acordo com o tamanho das partículas do material particulado, podendo chegar a escalas nanométricas, a inalação deste material pode causar lesões graves no organismo, pois têm a capacidade de atingir órgãos internos. O estudo é baseado na amostragem do material particulado proveniente dos gases de motores alimentados com diesel e/ou biodiesel em diferentes proporções de combustível e ar ambiente com impactador em cascata; determinando metais e arsênio na atmosfera de diferentes localidades do estado do Rio de Janeiro e no material particulado dos gases de escape de motores de ônibus/caminhão (EURO III), por intermédio de abertura ácida do material coletado e da técnica analítica ICP-OES. Os resultados obtidos para motor EURO III variaram de 100 a 10000 ng m-3, com a redução de emissão conforme adição de biodiesel no diesel sendo comprovada. Porém, em todas as proporções de combustíveis empregadas, houve grande incidência de emissão de partículas em escala manométrica, sendo esse comportamento também observado nas amostragens em ar ambiente. Neste caso, teores de 1,0 a 45,0 ng m-3 evidenciaram Caxias e Madureira como locais mais poluídos dos amostrados. Ni é o metal que possui situação mais alarmante, pois em todos os tamanhos de partícula e locais amostrados, os teores deste elemento foram superiores ao permitido pela legislação internacional. A análise estatística multivariada propôs que os combustíveis B10 e B15 são quimicamente semelhantes, enquanto B5 e B20 sofrem fortes alterações no decorrer de sua combustão e a correlação de Pearson mostrou em ar ambiente, que locais com níveis próximos de poluição apresentaram similaridade nos resultados, a qualidade do ar de Madureira é afetado predominantemente pela construção civil e tráfego, a presença da Baía de Guanabara ao redor da Cidade Universitária influencia nas emissões, a refinaria em Caxias é responsável por emissões importantes de metais e no Parque Nacional de Itatiaia , ao contrário de que se supunha, não está totalmente livre de poluição
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Stabilisation/solidification (S/S) is an effective technique for reducing the leachability of contaminants in soils. Very few studies have investigated the use of ground granulated blast furnace slag (GGBS) for S/S treatment of contaminated soils, although it has been shown to be effective in ground improvement. This study sought to investigate the potential of GGBS activated by cement and lime for S/S treatment of a mixed contaminated soil. A sandy soil spiked with 3000mg/kg each of a cocktail of heavy metals (Cd, Ni, Zn, Cu and Pb) and 10,000mg/kg of diesel was treated with binder blends of one part hydrated lime to four parts GGBS (lime-slag), and one part cement to nine parts GGBS (slag-cement). Three binder dosages, 5, 10 and 20% (m/m) were used and contaminated soil-cement samples were compacted to their optimum water contents. The effectiveness of the treatment was assessed using unconfined compressive strength (UCS), permeability and acid neutralisation capacity (ANC) tests with determination of contaminant leachability at the different acid additions. UCS values of up to 800kPa were recorded at 28days. The lowest coefficient of permeability recorded was 5×10(-9)m/s. With up to 20% binder dosage, the leachability of the contaminants was reduced to meet relevant environmental quality standards and landfill waste acceptance criteria. The pH-dependent leachability of the metals decreased over time. The results show that GGBS activated by cement and lime would be effective in reducing the leachability of contaminants in contaminated soils.
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当前,水资源污染越来越严重,人类的健康面临着巨大的威胁。高级氧化技术作为一 种经济、高效、无二次污染的水体处理方法,一直是水污染控制与治理领域研究的热点。 本文以环境中典型的有机污染物苯酚和水体中主要有机物腐殖酸为研究对象,利用自 制的紫外光(ultraviolet,UV)离线降解装置,采用紫外-可见光谱法和总有机碳(TOC) 分析法分别研究水相中苯酚、腐殖酸的紫外光降解情况,系统地考察不同初始pH值、初始 浓度、光照时间、光照强度、反应容器等因素对光降解效果的影响。为了模拟实际水体条 件和提高光降解效率,在体系中分别加入NaCl、Na2CO3、NaNO3、NaNO2和双氧水等化学 成分,探讨这些化学物质对苯酚、腐殖酸的紫外光降解效率和降解途径的影响。最后,首 次构建了石英螺旋管内壁负载TiO2膜的在线降解装置,结合UV/H2O2/TiO2联用体系,进行 海水中有机物的光降解研究。 紫外可见光谱分析表明:光降解速率随初始pH 值的降低而提高,相同条件下苯酚在 酸性溶液中降解速率高于碱性溶液,说明苯酚分子比酚氧离子容易光降解;硝酸钠和亚硝 酸钠有利于苯酚的光降解,说明它们在紫外光下容易分解生成自由基;在苯酚水溶液中加 入双氧水,光照15 min 后,光降解效率达到97%。各种介质中苯酚的降解速率大小依次为: 1.5 mmol/L 过氧化氢溶液 > 1.0 mmol/L 硝酸钠的海水 > 海水 > 纯水 > 0.5 mol/L 氯化钠溶液。然而,TOC 数据显示氯化钠的存在对苯酚的矿化有促进作用;同光谱的降解 速率相比,矿化速率要小。 腐殖酸的光降解效率随初始质量浓度的减小而提高,当质量浓度为10 mg/L时,光照 30 分钟后,降解效率高达到88%;初始pH值对腐殖酸的降解效率影响很大,腐殖酸在碱 性条件下比在中性和酸性条件更容易光降解;硝酸钠等盐分对中性和碱性溶液中腐殖酸的 光降解没有明显促进作用,但对酸性溶液中腐殖酸的光降解促进作用明显。采用UV/H2O2联 合降解时,腐殖酸降解效率得到显著提高。 相比离线降解方式,采用石英螺旋管在线降解苯酚和腐殖酸,降解效率均提高了15 倍 以上;海水经过在线降解后,紫外可见光光谱吸光度值缓慢下降;经过多次在线光降解后, 在290 nm波长处出现强烈吸收峰,再次光照后很快消失。这种现象表明海水中可能存在着 粒
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Horseflies are economically important blood-feeding arthropods and also a nuisance for humans and vectors for filariasis. They rely heavily on the pharmacological properties of their saliva to get a blood meal and suppress immune reactions of hosts. Little information is available on antihemostatic substances in horsefly salivary glands; especially no horsefly immune suppressants have been reported. By proteomics or peptidomics and coupling transcriptome analysis with pharmacological testing, several families of proteins or peptides, which act mainly on the hemostatic system or immune system of the host, were identified and characterized from 30,000 pairs salivary glands of the horsefly Tabanus yao (Diptera, Tabanidae). They are: (i) a novel family of inhibitors of platelet aggregation including two members, which possibly inhibit platelet aggregation by a novel mechanism and act on platelet membrane, (ii) a novel family of immunosuppressant peptides including 12 members, which can inhibit interferon-gamma production and increase interleukin-10 secretion, (iii) a serine protease inhibitor with 56 amino acid residues containing anticoagulant activity, (iv) a serine protease with anticoagulant activity, (v) a protease with fibrinogenolytic activity, (vi) three families of antimicrobial peptides including six members, (vii) a hyaluronidase, (viii) a vasodilator peptide, which is an isoform of vasotab identified from Hybomitra bimaculata, and interestingly (ix) two metallothioneins, which are the first metallothioneins reported from invertebrate salivary glands. The current work will facilitate the understanding of the molecular mechanisms of the ectoparasite-host relationship and help in identifying novel vaccine targets and novel leading pharmacological compounds.
Resumo:
Blood-feeding arthropods rely heavily on the pharmacological properties of their saliva to get a blood meal and suppress immune reactions of hosts. Little information is available on antihemostatic substances in horsefly salivary glands although their sal
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Estrogenic activities of emission samples generated by fossil fuel combustion were investigated with human estrogen receptor (ER) recombinant yeast bioassay. The results showed that there were weak but clear estrogenic activities in combustion emissions of fossil fuels including coal, petroleum, and diesel. The estrogenic relative potency (RP) of fossil fuel combustion was the highest in petroleum-fired car, followed by coal-fired stove, diesel-fired agrimotor, coal-fired electric power station. On the other hand, the estrogenic relative inductive efficiency (RIE) was the highest in coal-fired stove and coal-fired electric power station, followed by petroleum-fired car and diesel-fired agrimotor. The estrogenic activities in the sub-fractions from chromatographic separation of emitted materials were also determined. The results indicated that different chemical fractions in these complex systems have different estrogenic potencies. The GC/MS analysis of the emission showed that there were many aromatic carbonyls, big molecular alcohol, PAHs and derivatives, and substituted phenolic compounds and derivatives which have been reported as environmental estrogens. The existence of estrogenic substances in fossil fuel combustion demands further investigation of their potential adverse effects on human and on the ecosystem. The magnitude of pollution due to global usage of fossil fuels makes it imperative to understand the issue of fossil fuel-derived endocrine activities and the associated health risks, particularly the aggregated risks stemmed from exposure to toxicants of multiple sources. (C) 2003 Elsevier Science Ltd. All rights reserved.
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研究了黄土沟壑区小流域塬面、坡地、梯田和沟道土壤微量元素的剖面分布特征,以揭示不同地形条件下微量元素的有效性及地球化学特性.结果表明,不同土层土壤全量微量元素的变异系数均小于15%,为小变异土壤性质,有效态和吸附态铁和锰的变异系数均高于36%,为高度变异土壤性质;有效态和吸附态锌和铜属于中到高度变异.全量铁、锰和铜以沟道土壤较高,全锌、有效态和吸附态微量元素含量以塬面土壤较高.不同形态微量元素的剖面分布趋势取决于地形条件.不同地形下成土过程及不同地形条件所对应的土地利用方式造成了全量微量元素的差异,而土壤有机质含量的差异是不同地形条件下有效态和吸附态微量元素剖面分布特征不同的主要原因.
Resumo:
以黄土高原南部地区的两个定位试验为基础,研究了旱地不同栽培和施肥模式对土壤微生物量碳、氮和可溶性有机碳、氮的影响。结果表明,秸秆覆盖显著提高土壤微生物量氮(SMBN)含量,地膜覆盖使SMBN含量显著降低;秸秆和地膜覆盖显著降低小麦拔节期和灌浆期土壤可溶性有机氮(SON)含量。适量施用化学氮肥(120kg/hm2)有利于小麦生长后期SMBN含量的升高,而过量施用(240 kg/hm2)显著降低SMBN含量。与不施肥处理相比,土地经长期撂荒后0-10 cm土层SMBC,SMBN,SOC和SON含量显著提高;氮磷钾配施有机肥显著提高小麦各生育期0-10,10-20 cm土层SMBC,SMBN,SOC和SON的含量;单施氮磷钾肥对土壤SMBC,SMBN含量无明显影响,提高土壤SOC,SON的平均含量。土壤SMBC,SMBN,SOC和SON含量两两之间呈极显著正相关关系,四者含量与土壤有机碳、全氮含量间的正相关关系也达显著或极显著水平。