排序方式: 共有18条查询结果,搜索用时 187 毫秒
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为了探索含络合铜电镀废水的处理新方法,以废铁屑为材料,研究其去除EDTA-Cu(Ⅱ)的有效性和作用机制。对铁屑进行XRD表征的结果表明,铁屑中含有零价铁和少量碳,实验发现,铁屑对Cu(Ⅱ)和EDTA能同步去除,90 min的去除率分别达到93.51%,52.55%,且降低了体系的生物毒性,提高了生物降解性。对反应机制进行探讨,结果表明铁屑以直接还原、沉淀吸附和微电解作用实现对EDTA-Cu(Ⅱ)的有效去除。 相似文献
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柠檬酸对3种常见水产病原菌的抑菌作用 总被引:1,自引:0,他引:1
选用嗜水气单胞菌、副溶血弧菌、荧光假单胞菌3种常见水产病原菌,用于测定柠檬酸的抑菌效果及最小抑菌浓度,并研究了柠檬酸抑菌作用的持续性。3种菌均为革兰氏阴性菌。试验结果表明,柠檬酸对3种菌都有不同程度的抑菌作用,并得到最小抑菌浓度,依次是:0.0011g/mL,0.0008g/mL,0.00125g/mL;在最小浓度下抑菌作用可达6d之久,柠檬酸抑菌效果有较好的持续性。 相似文献
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使用Vibrio fischeri发光细菌法,评价了工业区和居民区大气颗粒物悬浮液的细菌毒性,并对颗粒物暴露后的老鼠毒性效应进行了分析和讨论;应用HRGC-HRMS研究了工业区大气中二噁英浓度水平及组分特征,并在此基础上开展了二噁英呼吸暴露风险评价.结果显示:工业区大气颗粒物的细菌毒性要明显高于居民区,表明急性毒性结果与局地污染排放密切相关;不同粒径分布的大气颗粒物细菌毒性结果产生显著差异,证明毒性成分主要吸附在较细粒径的颗粒物上.强有力的证据表明,颗粒物暴露后的肺组织病理损伤与氧化性自由基过量产生有关,因此与自由基相关的毒理机制可作为下一步深入研究的路径.4个采样点主动采样、被动采样和大气沉降样品二噁英浓度范围分别为0.034~1.29pg/m3、0.031~0.103pg/m3和0.226~4.67pg/(m2·d),平均值分别为0.366pg/m3、0.063pg/m3和1.82pg/(m2·d);优势组分分别为2,3,4,7,8-PeCDF、2,3,4,6,7,8-HxCDF、1,2,3,6,7,8-HxCDF和1,2,3,4,7,8-HxCDF,2,3,4,7,8-PeCDF、1,2,3,7,8-PeCDD、2,3,7,8-TCDD和2,3,7,8-TCDF,2,3,4,7,8-PeCDF、1,2,3,7,8-PeCDD、2,3,4,6,7,8-HxCDF和1,2,3,6,7,8-HxCDF.成人和儿童呼吸暴露量最大值分别为9.74×10-2pg/(kg·d)和1.28×10-1pg/(kg·d),均低于0.4pg/(kg·d)(呼吸进入人体的每日允许摄入量),表明暴露风险处于可接受水平. 相似文献
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Xuewen Yi Zhanqi Gao Lanhua Liu Qian Zhu Guanjiu Hu Xiaohong Zhou 《Frontiers of Environmental Science & Engineering》2020,14(6):109
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Complex mixtures of toxic substances occurring in surface waters are difficult to characterise by chemical analyses because each compound occurs at a very low concentration and requires a specific analytical method to be identified. Ecotoxicological tests on water extracts can be used as a screening tool to evaluate quickly and simply the overall quality of a water body with regard to micropollutant contamination. In this work, a pre-concentration procedure based on solid-phase extraction (SPE), suitable for both biological testing and analytical determination, is proposed. The extraction procedure is an improved version of a methodology used to evaluate the toxicity of organic micropollutants occurring in surface waters. It offers the advantage of using disposable commercial cartridges, which are easier to manage than the columns prepared with macromolecular resins. Water extracts from two representative Italian rivers, characterised by a different gradient of potential contamination and prepared according to the new concentration techniques, are used. The acute toxicity of the water extracts is tested on Daphnia magna and the bioluminescence inhibition in Vibrio fischeri. Criteria based on the concentration factor (CF) are proposed for assessing the hazard to aquatic life due to the exposure to toxic substances in surface waters. The aim of hazard ranking is to focus analytical efforts towards those samples that show the highest toxic potential. 相似文献
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舟山市海洋贝类生物体内的细菌学研究 总被引:1,自引:0,他引:1
对浙江省舟山市各区县海洋贝类体内细菌数量及优势细菌种类进行了初步研究。根据2004年8月的采样和实验室分析,结果表明,贝类生物体内的优势种为少动鞘氨醇单胞菌、温和气单胞菌、欧文氏菌属等,一些能够诱发疾病的如杀鲑气单胞菌、溶藻弧菌、腐败假单胞菌等的出现应当引起重视。对生物体内的细菌数量检测发现,弧菌和粪大肠菌群数量都比较高,弧菌的测值范围为50个/克~1.8×104个/克,几何平均为9.3×102个/克;粪大肠菌群的测值范围为2.0~23个/克,几何平均为12.0个/克,超国家海洋生物体内粪大肠菌群二类标准,超标率为91.7%。 相似文献
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Celina M. Junges Eduardo E. Vidal Andrés M. Attademo Melisa L. Mariani Leandro Cardell Antonio C. Negro 《Journal of environmental science and health. Part. B》2013,48(3):163-170
The H2O2/UVC process was applied to the photodegradation of a commercial formulation of glyphosate in water. Two organisms (Vibrio fischeri bacteria and Rhinella arenarum tadpoles) were used to investigate the toxicity of glyphosate in samples M1, M2, and M3 following different photodegradation reaction times (120, 240 and 360 min, respectively) that had differing amounts of residual H2O2. Subsamples of M1, M2, and M3 were then used to create samples M1,E, M2,E and M3,E in which the H2O2 had been removed. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were measured in tadpoles to determine possible sub-lethal effects. In V. fischeri, M1,E, which was collected early in the photodegradation process, caused 52% inhibition, while M3,E, which was collected at the end of the photodegradation process, caused only 17% inhibition. Survival of tadpoles was 100% in samples M2, M3, and in M1,E, M2,E and M3,E. The lowest percentages of enzymatic inhibition were observed in samples without removal of H2O2: 13.96% (AChE) and 16% (BChE) for M2, and 24.12% (AChE) and 13.83% (BChE) for M3. These results show the efficiency of the H2O2/UVC process in reducing the toxicity of water or wastewater polluted by commercial formulations of glyphosate. According to the ecotoxicity assays, the conditions corresponding to M2 (11 ± 1 mg a.e. L?1 glyphosate and 11 ± 1 mg L?1 H2O2) could be used as a final point for glyphosate treatment with the H2O2/UV process. 相似文献