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971.
Sheng Huang Xin Zhao Yanqiu Sun Jianli Ma Xiaofeng Gao Tian Xie Dongsheng Xu Yi Yu Youcai Zhao 《Frontiers of Environmental Science & Engineering》2017,11(1):12
Exploration of heavy metals and organic pollutants, their leaching capacity along with health and environmental risks in contaminated industrial construction and demolition waste (ICDW) within a pesticide manufacturing plant were investigated. A maximum content of 90.8 mg?kg–1 Cd was found present in the wastes, which might originate from phosphorus rocks and industrial sulfuric acid used in pesticide production processes. An average concentration of 979.8 mg?kg–1 dichlorovos and other 11 organophosphorus pesticide were also detected. Relatively high leaching rates of around 4.14‰were obtained from laboratory simulated ICDW using both glacial acetic acid-sodium hydroxide and deionized water. Pesticide pollutants had the strongest tendency to retaining on dry bricks (leaching rate 1.68‰) compared to mortar-coatings, etc. due to their different physical characteristics and octanol-water partioning coefficient. Mobility of pesticide from on-site ICDW by water was spatially correlated to waste types, process sections and human activities, with a flux of leaching rate between 5.9‰ to 27.4%. Risk-based corrective action (RBCA) model was used to simulate the risk of contaminated ICDW debris randomly scattered. Oral and dermal ingestion amount by local workers was 9.8 × 10–3 and 1.9 × 10–2 mg?(kg?d)–1, respectively. Potential leaching risk to aquatic systems exceeded the limit for nearly 75% waste. Environmental and health risk exceedance was found in most ICDW, while the risk value of the most severely contaminated brick waste was 660 times beyond critical level. Implications for waste management involving construction and deconstruction work, waste transferring and regulation supplying were also provided.
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972.
973.
4种喹诺酮类抗生素对发光菌毒性作用研究 总被引:3,自引:0,他引:3
分析了4种常见的喹诺酮类抗生素(QNs)对发光菌(Photobacterium phosphoreum)的单一毒性和等毒性比例下的联合毒性作用,基于毒性单位法(TU)、相加指数法(AI)和混合毒性指数法(MTI)评价混合体系联合毒性的作用类型。加替沙星、洛美沙星、左氧氟沙星和诺氟沙星4种喹诺酮类医药品对发光菌的半数效应浓度(EC50)分别为:0.084×10~(-3)、0.137×10~(-3)、0.129×10~(-3)和0.151×10~(-3)mol·L-1。不同的评价方法对4种QNs的联合效应评价结果具有较好的一致性,多元混合体系呈现为不同程度的拮抗作用。结合分子结构特征和不同取代基相互作用,初步分析了联合毒性机理,进一步的毒性作用机制还需通过对生物生理生化反应等进行深入研究。本研究多种QNs混合体系呈现拮抗作用为主,揭示了此类医药品在环境中的联合使用可能导致药效降低以及微生物耐药性的产生和传播。 相似文献
974.
Electrophoresis release test (ERT) was established by our lab to observe the re-released hemoglobin (Hb) from red blood cells (RBCs) and whole blood. In this study, ERT was performed to study the effects of different plasma components including plasma, serum, albumin, globulin, fibrinogen, glucose, amino acid, vitamin, insulin, hormone, and inorganic ions on re-released Hb from RBC and whole blood samples during ERT. The results showed that plasma, serum, albumin, globulin, compound amino acid, essential amino acid, vitamin C, insulin, hormone, NaCl, KCl, CaCl2, and NaHCO3? decreased re-released RBC Hb; while glucose, vitamin B1, vitamin B2, and vitamin B12 elevated re-released RBC Hb. The differing effects of various plasma components on re-released Hb of RBC may play a significant role in blood conservation. 相似文献
975.
A holistic approach towards assessment of severity of land degradation along the Great Wall in northern Shaanxi Province,China 总被引:26,自引:0,他引:26
The farming and grazing interlocked transitional zone along theGreat Wall in northern Shaanxi Province is particularly vulnerable to desertification due to its fragile ecosystem and intensive human activity. Studies reveal that desertification isboth a natural and anthropogenic process. Four desertificationindicators (vegetative cover, proportion of drifting sand area, desertification rate, and population pressure) were used to assess the severity of desertification in a GIS. The first threefactors were derived from multitemporal remote sensing and landinventory data. The last factor was calculated from census data.It was found that the overall severity of land degradation in thestudy area has worsened during the last two decades with severely, highly and moderately degraded land accounting for 84.2% of the total area in 1998. While the area affected by desertification has increased, the rate of desertification has also accelerated from 0.74 to 0.87%. Risk of land degradation in the study area has increased, on an average, by 155% since 1985. Incorporation of both natural and anthropogenic factors inthe analysis provides realistic assessment of risk of desertification. 相似文献
976.
马尾松在不同浓度铝溶液(0、30、60、120、240、480ppm)中生长两个月后,转移至高温、低温、干旱或SO_2熏气罩中,结果发现,经过铝培养松苗的膜透性显著高于未经过铝培养松苗的膜透性,且铝浓度越大,膜透性越大,表明铝处理马尾松对高温、低温、干旱和SO_2的抵抗性降低.300ppb的SO_2熏气30h后,未经铝培养的松苗没有明显受害症状出现,而经过铝培养的松苗却表现出针叶发黄、叶缘和叶尖出现明显可见伤害斑点等SO_2受害症状,高温、低温和干旱处理的主要症状表现为针叶发黄、萎蔫。 相似文献
977.
本文研究了废水中痕量硝基酚类的高效液相色谱分离、测定方法。在碱性条件下,硝基酚类的最大吸收波长移向360~420hm范围内,以λ=395nm作的检测波长进行测定,提高了分析方法的灵敏度和选择性。同时,研究了不同流动相、检温等因素对分离的影响,确定了最佳流动相组成。样品分析采取直接水溶液进样法简化了预处理步骤。检测下限达10~(-10)g/m1。 相似文献
978.
979.
Gao Qing xian Ren Zhen hai Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China. E mail: gaoqx@public.east.cn.net Zhang Yun gang Center of Satellite Meteorology Beijing China Zhang Cheng chang Beijin 《环境科学学报(英文版)》1999,(3)
1 IntroductionOzoneisoneofthetracegasesinatmosphere.Itcanabsorbnearlyallsolarultravioletradiation(UVB)rangedfrom0-20—0-35μm.Thechangeofstratosphericozoneconcentrationanditsverticalstructurewillinfluencethetemperaturestructureofstratosphere.Thedecrea… 相似文献
980.