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61.
我国环保产业研究现状分析——基于宏观视角的文献述评   总被引:1,自引:0,他引:1  
通过文献研究法,基于宏观视角对我国环保产业研究成果进行梳理。当前,我国的环保产业研究成果初具规模,研究重点在于环保产业的现状分析、问题探讨以及对策研究,包括环保产业各主体间博弈均衡、环保产业的技术支持、投融资机制等内容。未来环保产业研究应注意环保产业竞争力的科学评价、环保产业主体间的良性互动及其合力的达成以及环保技术评价和兑现。  相似文献   
62.
在收集和分析对生态工业发展研究的文献基础上,将影响生态化工产业发展的因素归纳为3大因素:直接因素、间接因素和机制性因素,6个二级指标,分别是自然因素、经济因素、技术因素、产业因素、社会因素、政策法规,同时针对全国第一化工大省山东省不同类型、不同地域的11家化工企业进行了实地调研,并对问卷调研数据进行了基于SPSS软件的克朗巴哈α系数的信度分析以及主成分分析,结果表明问卷具有良好的信度,并按各二级指标中所含因素的重要程度确定了影响生态化工产业发展的12个主要因素,在此基础上提出了化工产业生态化发展的建议,为化工产业生态化建设提供相应的理论支撑。  相似文献   
63.
Lee DJ 《Chemosphere》2006,63(11):1903-1911
The alkalinity of cementitious materials rectifies a low pH of leachant to be over 12 in leaching. The rapid change of leachant pH produces the remarked variation of solubility of heavy metals in the toxicity characteristic leaching procedure. The release of lead on cementitious solid waste forms in leaching was observed in the pH range of particularly 12. The release of lead is significant dependant on the changed values of leachant pH. The pH static leaching procedure (PSLP) was implemented for assessing a quantitative measurement of total potential leachability with the continuing addition of acidic leachant up to the point of no change of leachant pH. The release of lead on Pb-doped solidified waste forms (SWF), in the PSLP, was 27.0% of initial concentration at the maximum meq CH3COOH (about 24.0) added to g dry solidified wastes. In this study, the immobilization effect of calcite on SWF was investigated in the acidic condition by the PSLP. Calcite additions to SWF make a good fixation efficiency of about 92%. Calcite addition abundantly provides the acid neutralization capacity to protect SWF from the attack of acid, with the marked development of hydrated minerals (mainly portlandite and C–S–H) in accordance with the accelerating effect of cement hydration.  相似文献   
64.
水泥粉尘经分级,并经吸湿和吸油处理,对所得尘样分别测定比电阻,从而找出湿度等对比电阻的变化规律、分析其产生原因,为改进和合理使用电除尘器提供依据。  相似文献   
65.
The interactions between cement and a clayey host-rock of an underground repository for intermediate-level radioactive waste are studied with the reactive transport code HYTEC for supporting performance assessment. Care is taken in using relevant time scales (100,000 years) and dimensions. Based on a literature review, three hypotheses are considered with respect to the mineralogical composition of the claystone and the neo-formed phases. In the long term, the pH is buffered for all hypotheses and important mineral transformations occur both in cement and the host-rock. The destruction of the primary minerals is localized close to the cement/claystone interface and is characterized by the precipitation of secondary phases with retention properties (illite, zeolite). However, beyond the zone of intense mineral transformations, the pore water chemistry is also disturbed over a dozen meters due to an attenuated but continuous flux of hydroxyl, potassium and calcium ions. Four interdependent mechanisms control the profile in the whole system: diffusion of the alkaline plume, mineralogical buffering, ion exchange and clogging of the pore space at the cement/claystone interface. The migration of a selected group of radionuclides (Cs, Ra, Tc and U) is explicitly integrated in the simulations of the strongly coupled system. Theoretical profiles of distribution coefficient (Kd) and solubility limit values are derived from the simulations, and their sensitivity with respect to the system evolution is estimated.  相似文献   
66.
水泥土搅拌桩复合地基静载试验检测法的安全度分析   总被引:2,自引:1,他引:1  
在检测水泥土搅拌桩复合地基的承载力能否达到设计要求时 ,最常用的方法是单桩静载试验法和复合地基静载试验法。工程实践中发现 ,采用这两种静载试验方法得到的检测结果存在较大差异。笔者根据水泥土搅拌桩的基本特性 ,结合工程实例 ,对这两种静载试验检测结果存在的差异及其安全度进行比较分析 ,得出单桩静载试验法结果的安全度高于复合地基试验法结果的结论 ,因此 ,提出了一些合理化建议  相似文献   
67.
分析了原设计中存在的问题,提出了改造措施和方案,并介绍了改造后的结果。  相似文献   
68.
从增加资金投入、推进技术创新等方面提出了加快发展我国环保产业的建议和措施。  相似文献   
69.
随着第三产业的快速发展 ,其带来的环境污染也日趋严重 ,这给我国环境管理工作提出了新的挑战。本文探讨了一项新的环境管理手段———环境信息公开制度在第三产业环境管理中的应用 ,并就这项手段的指标体系做了初步的研究  相似文献   
70.
The use of regulatory and compliance-based modeling for air quality impact assessment is invariably relied upon to predict future air quality under various management scenarios particularly where air quality monitoring data are limited. This paper examines the dispersion from a multi-stack cement manufacturing complex with associated quarries and transport activities for regulatory compliance under uncertain emission and meteorological conditions. The concentrations of CO, NOx, SO2 and PM at sensitive receptor locations were used as indicators in comparison to World Health Organization (WHO) interim guidelines. Exceedance exposure areas were delineated under bounded uncertainties in input emission factors and meteorological parameters. Planning and management initiatives were tested to control/minimize potential exposure. Compared to the case of low emissions and actual meteorological conditions, the consideration of worst emissions coupled to worst meteorological conditions enlarged the boundaries of the exceedance exposure areas considerably. The implementation of best available technologies and enforcement of emission standards improved air quality in the region significantly and lowered the exposure at many population centers to below health standards. Uncertainty in the output of atmospheric dispersion models continues to play a significant role to be considered at the point where science is translated into political decision making.  相似文献   
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