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951.
952.
以模拟烟气为气源,去离子水为水源,通过微纳米气泡发生器形成微纳米气液分散体系,吸收模拟烟气中的NO,考察了多种因素对脱硝率(η)和气相体积总传质系数(KGa)的影响,分析了微纳米气液分散体系吸收NO的反应机理。结果表明:η和KGa随着进气NO体积分数和十二烷基苯磺酸钠(SDBS)质量浓度的提高而下降;随着吸收液初始pH的提高先降低后升高;随着进气O_2体积分数的增大而提高;随着吸收液温度的升高先提高后降低;控制进气NO体积分数为0.06%时,在吸收液初始pH为2.0、吸收剂为去离子水、吸收液温度为25℃、进气O_2体积分数为10%的最佳条件下,脱硝率可达81.0%。微纳米气液分散体系是通过产生羟基自由基从而对NO进行氧化吸收的。 相似文献
953.
危险废物稳定化/固化技术的现状与发展 总被引:1,自引:0,他引:1
本文对危险废物稳定化/固化处理技术的历史、现状以及今后的发展方向进行了较为系统的论述,对该技术在处理危险废物时所存在的问题进行了探讨,认为今后药剂稳定化技术在废物处置预处理领域将会占据重要的地位。 相似文献
954.
955.
浅析化工项目环境影响评价要点 总被引:1,自引:0,他引:1
化工项目的环境影响评价应严格执行有关的法律、法规和导则,并结合行业特点执行特定的条例和规范。在其评价过程中应确保工程分析数据的可靠性和措施的可行性,对是否符合清洁生产进行详细阐述,针对事故风险进行评价并提出防范措施,最后对有毒废渣的处理提出要求。 相似文献
956.
In order to find out an alternative to traditional environmental policies in the State of São Paulo (Brazil), which have been mainly focused on legal standard compliance for air and water emissions, as well as in soil contamination, the Environmental Agency of São Paulo State — CETESB — launched a research project entitled Industrial Toxic Substances Use Reduction Programme. The project was launched in 2006 with funding from the United States Trade and Development Agency. Its aim was to propose new policies and strategies to reduce industrial releases of toxic compounds to the environment. Its general steps were the identification of an initial toxic chemical targets list; a review of successful programmes in the United States; the development of key elements and the establishment of alternative combinations of those elements for the implementation of an indigenous programme. Since project completion, CETESB has been discussing the possibility of implementing the results through a pilot project being developed jointly with industry representatives. This pilot project will serve as a model for a broader industrial toxic substances reduction programme to be implemented in São Paulo State. 相似文献
957.
ABSTRACT: Bivalves are used as bioindicators to assess trends of the chemical quality of coastal and marine environments due to their ability to concentrate chemicals. These shellfish are subject to seasonal physiological changes influencing the chemical concentration. Using quarterly data, we model concentration via linear regression with a biologically based seasonal component. This was applied to cadmium concentration measured in the blue mussel (Mytilus edulis) at three sites in the Seine estuary (Normandy, France). In this case we have a high concentration season from January to June and a “low concentration” season from July to December. This season definition was checked a posteriori, using box-and-whisker plots and a statistical test of comparison of pair-wise adjusted least-squares mean differences, and it appears to be very reasonable. We averaged data by season and across sites. Our final model (R2= 0.846 with N= 27 observations) includes highly significant terms: a season effect, which accounts for 45% of the total variability, a linear and a quadratic time term. Outliers were identified by high Studentized residual values and attributed to bias in the temporal sampling schemes. The methodology developed will further be used with other shellfish and/or other trace elements and organic chemicals. 相似文献
958.
本文研究了我国重酸雨地区四川,贵州省湖塘溪流的水化学组成及离子平衡关系,结果表明:城郊之间水化学组成存在差异;同时,进行离子平衡衡算时,须对溶解态钙,镁进行校正,否则,会出现阴离子短缺现象,仅由钙,镁及硫酸根和弱酸根组成的简单离子平衡也是大致符合的,但其应用有一定的局限性。 相似文献
959.
本文讨论了将硫酸亚铁剂量计和铜-铁剂量计用于强脉冲混合辐射场测定的实验设计,利用直径220毫米的聚乙烯球,将硫酸亚铁剂量计的快中子响应降低到20%以下,由它和完全暴露在中子、γ混合场中的硫酸亚铁剂量计响应之差,测量中子吸收剂量。这种方法两次实际用于强脉冲混合辐射场中子、γ吸收剂量测量,得到的结果和热释光剂量计、固体径迹探测器的测量结果进行了比较,在±25%的误差范围内一致 相似文献
960.
William Back Bruce B. Hanshaw 《Journal of the American Water Resources Association》1971,7(5):1008-1016
ABSTRACT. Interest in the geochemistry of groundwater is increasing owing to the great number of current projects involving underground liquid waste storage, artificial recharge of potable water, accidental contamination of groundwater bodies, sanitary landfills, and pollution monitoring. Geochemical techniques used to facilitate the understanding of a groundwater system range from extremely simple to those requiring sophisticated theories, equipment, and procedures. An interpretation of the simple trilinear diagram for samples collected from the Yucatan Peninsula of Mexico provided evidence that the fresh-water body was only a few tens of meters thick and was underlain everywhere by an extensive body of salt water. A geochemical technique that has been used effectively to identify the source of salt water in coastal aquifers is measurement of the carbon-14 concentrations. Carbon-14 has been used in a regional carbonate aquifer to determine the velocity of groundwater movement, rates of chemical reactions, and distribution of hydraulic conductivity. The application of principles of irreversible thermodynamics to groundwater systems provides a basis for constructing models which permit prediction, over both time and space, of changes in head distribution and chemical character of the water resulting from imposed stresses on the system. In essence, proper application of irreversible thermodynamics combines the potential theory of Hubbert with principles of reversible chemical thermodynamics, such as solution of carbonate minerals, to describe and explain controlling chemical reactions and processes of groundwater systems. 相似文献