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氨浸出含锌烟尘制取活性氧化锌 总被引:3,自引:0,他引:3
采用氨浸出法处理含锌烟尘,浸出液在微波-超声波联合作用下蒸氨得碱式碳酸锌沉淀,再经煅烧制得活性氧化锌.实验结果表明:在总氨浓度为9.0 mol/L、浸出温度为40 ℃、浸出液初始pH为 11.0~11.5、搅拌转速为400 r/min、浸出剂体积与含锌烟尘质量比为4、浸出时间为60 min的浸出条件下,锌的浸出率为83.3%.浸出液经过两段净化除杂后,在超声波功率50 W、微波辐射(微波功率随温度的设定而自动变化)的联合作用下,使溶液体系恒温90 ℃,进行蒸氨,沉淀得到前驱体碱式碳酸锌,经煅烧,得到平均直径为0.4 μm、晶型为六方晶系、片状的活性氧化锌. 相似文献
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Ling Zhang Lu Wang Kedong Yin Ying Lv Derong Zhang 《Environmental pollution (Barking, Essex : 1987)》2009,157(11):2957-2963
In this study, the natural Cu background concentration and Cu natural and anthropogenic contamination in soil, water and crop were investigated systematically in Huangshi area. The results show that regional geology is the dominant factor controlling the natural Cu background concentration in soil and water, and that pH is important to control the vertical distribution of Cu in soil under the same geographical and climatic conditions. The mineralization of rock bodies causes the natural Cu increase in soil and water, whereas, a large number of mining–smelting plants and chemical works are the main sources of Cu anthropogenic contamination. Cu in naturally and anthropogenically polluted soil displays differences in total and available contents, vertical distribution patterns and physico-chemical properties, the same happens in water. 相似文献
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利用自行开发的混合呼吸速率测量仪在接种污泥的条件下对重庆某城市污水处理厂污水进行了呼吸速率测试(短期BOD测试,以呼吸速率测量重新进入内源呼吸阶段为结束);同时应用美国产BI-2000电解质呼吸仪在不接种污泥的条件下对该污水进行了BOD测试(长期BOD测试,理论上以污水中所有有机物矿化为结束)。对2种测试方法及其结果进行了比较,结果表明,2种方法得到的BCOD存在很大差异,短期BOD测试方法得到的结果仅为长期BOD测试方法得到的结果的40%~60%。通过批式呼吸测量方法测定了原废水中的活性异养微生物浓度XH(0),结果表明,XH(0)与BCODst之和与BCODlt比较接近,两者之比在0.88~1.02之间,平均值为0.94。 相似文献
999.
As part of a comprehensive environmental management system, many countries establish emission control targets for mass emissions of a pollutant. Such targets are often the key objective of an environmental policy, such as an emission trading program. In China, however, it is more than just an objective of one particular policy; it has become a concept that has influenced many national environmental policies and activities. The objective of this article is to review the implementation of the total emission control policy in the past 10 years and explore emerging issues in its implementation. The article has three sections: a summary of the implementation experience, issues with the design and implementation of the policy, and policy recommendations. 相似文献
1000.
Sue Ellen Haupt Anke Beyer-Lout Kerrie J. Long George S. Young 《Atmospheric environment (Oxford, England : 1994)》2009,43(6):1329-1338
Assimilating concentration data into an atmospheric transport and dispersion model can provide information to improve downwind concentration forecasts. The forecast model is typically a one-way coupled set of equations: the meteorological equations impact the concentration, but the concentration does not generally affect the meteorological field. Thus, indirect methods of using concentration data to influence the meteorological variables are required. The problem studied here involves a simple wind field forcing Gaussian dispersion. Two methods of assimilating concentration data to infer the wind direction are demonstrated. The first method is Lagrangian in nature and treats the puff as an entity using feature extraction coupled with nudging. The second method is an Eulerian field approach akin to traditional variational approaches, but minimizes the error by using a genetic algorithm (GA) to directly optimize the match between observations and predictions. Both methods show success at inferring the wind field. The GA-variational method, however, is more accurate but requires more computational time. Dynamic assimilation of a continuous release modeled by a Gaussian plume is also demonstrated using the genetic algorithm approach. 相似文献