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881.
882.
883.
介绍了电除尘器极板电泳密度测试方法和装置,测定了不同极距下脉冲供电和直流供电时,沿电晕极线垂直方向、水平方向及整个极板上电流密度的分布结果,得出在同等条件下,脉冲供电的极析电流密度分布比直流供电的更加均匀,有利于改善电除尘器运行。  相似文献   
884.
正The global and regional redistribution of mercury within the environment is of primary importance to both natural ecosystems and human health.The ratification of the Minamata Convention on Mercury by 91 parties represents a key step in protecting ecosystems and future societies from increasing mercury accumulation.However,key to the continued quanti-  相似文献   
885.
This study aims to investigate the impact of MSW landfill on the contamination of phthalate esters (PAEs) in nearby environment. Landfill leachate, surface water, groundwater and soil profile samples were collected from a MSW landfill area in Wuhan, China. Contents of 16 PAEs were detected for each sample using gas chromatography method. Results showed that landfill had an obvious effect on the contamination of PAEs in groundwater, whereas showed no tremendous effect on the PAEs contamination in surface water and topsoil. Seven possible transportation processes of PAEs in landfill area were put forward. However, the especially important processes are the invasion of PAEs into aquifer through weathered crevice, horizontal transportation in aquifer and upward infiltration with groundwater. It is suggested that the whole landfill area should be engineered with seepage-proof membrane and clay so as to prevent landfill leachate from flowing out of the filling area. On the other hand, no weathering crevice is permitted in the landfill area as it will affect groundwater seriously.  相似文献   
886.
自焙阳极铝电解槽在生产过程中产生的大量有害气体和粉尘 ,在我国至今没有一种有效的治理方法。我院首次应用电除尘与静电凝聚技术相结合 ,净化自焙阳极铝电解槽生产过程中所产生的有害气体和烟尘获得成功。经国家环保部门测试认定 ,其沥青烟、氟化物和粉尘的排放量均低于国家排放标准。该项技术为我国铝电解行业消除对环境的污染提供了一种最佳的治理方法。介绍了净化工艺原理、实施方法、技术效果与现场运行实测数据  相似文献   
887.
Time domain reflectometry (TDR) is a prospective measurement technology for moisture content of sewage sludge composting material; however, a significant dependence upon temperature has been observed. The objective of this study was to assess the impacts of temperature upon moisture content measurement and determine if TDR could be used to monitor moisture content in sewage sludge compost across a range of temperatures. We also investigated the combined effects of temperature and conductivity on moisture content measurement. The results revealed that the moisture content of composting material could be determined by TDR using coated probes, even when the measured material had a moisture content of 0.581 cm3 cm?3, temperature of 70 °C and conductivity of 4.32 mS cm?1. TDR probes were calibrated as a function of dielectric properties that included temperature effects. When the bulk temperature varied from 20 °C to 70 °C, composting material with 0.10–0.70 cm3 cm?3 moisture content could be measured by TDR using coated probes, and calibrations based on different temperatures minimized the errors.  相似文献   
888.
In this study, field measurements were conducted to estimate and characterize the atmospheric emission levels and profiles of polychlorinated biphenyls (PCBs) from multiple industrial thermal processes. The emission levels and profiles of PCBs from five types of thermal processes at twenty-three plants were studied and compared with eight processes reported in our previous studies. Correlation analysis was preformed to identify a marker congener for emission of ΣPCB. A significant correlation was observed between congener CB-118 and ΣPCB (R2 = 0.65 and p < 0.01), which suggests that CB-118 is a good marker congener for emission of ΣPCB. The profiles of PCBs emitted from the thirteen thermal processes were compared, and this information could be used for studying source–receptor relationships and identifying the specific sources of PCBs. To prioritize the sources for control, the concentrations of PCBs from thirteen industrial thermal sources were compared. The PCB concentrations from secondary zinc smelting and thermal wire reclamation were about one to three order magnitude higher than those of other sources, which suggests that these two sources be given priority in PCB source control. Finally, the atmospheric emission factors of PCBs from the thirteen industrial sources were summarized, and these data will be useful for developing an integrated emission inventory of PCBs.  相似文献   
889.
La2O3—ZrO2缺陷萤石型燃烧催化剂的制备   总被引:7,自引:0,他引:7  
杨乐夫  陈笃慧 《环境化学》1999,18(3):198-204
缺陷萤石型La2O3-ZrO2固溶体的催化燃烧活性受制备条件的影响,本文通过对其共沉淀前体的表面结构和热分解过程的分析,发现共沸蒸馏的办法可以有效地控制前体表面羟基的缩合过程,减少团聚,保持前体中金属离子均匀分散,为生成缺陷有序的烧结石型的La2Zr2O7复氧化物提供了可能。复合氧化物固溶体的表面阳离子配置情况与样品的催化氧化性能密切相关,软团聚前体的烧结产物对甲烷燃烧反应具有更高的催化活性。  相似文献   
890.
石油行业,特别是石油钻井行业历来被认为是个高风险、多事故的行业.受钻井公司HSE 管理委员会的委派,安全监督对所负责施工现场的QHSE 管理实施全员、全方位、全天候、全过程的监督管理;监督现场所有的施工单位、人员、施工作业严格执行钻井公司QHSE 管理体系的相关规定,对生产现场违章指挥、违章操作、违反劳动纪律及其它违反企业安全管理规章制度、体系文件的现象进行纠正、制止并给予经济处罚.为了规范安全监督人员的行为和管理工作,公正、合理地评价每位驻井安全监督的工作业绩和管理水平,应通过加大对安全监督的考核力度,激励安全监督人员加强理论知识的学习和责任心,不断提高生产现场的监督管理水平.  相似文献   
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