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271.
本文阐述了地下水污染潜势评估的重要性,介绍了三种方法,对其中的废物-土址-地点相互作用列表法作了详细介绍,并将WSSIM法用于四川省什邡县化工开发区地下不污染潜势估。 相似文献
272.
Robert B. Olshansky 《Environmental management》1996,20(1):11-23
The California Environmental Quality Act (CEQA) has evolved from a mini-NEPA, first enacted in 1970, into a procedural act
that affects the approval process of all large developments in California. In 1990, California local governments produced
over 1600 environmental impact reports and 30,000 initial studies under CEQA. Because of its widespread use, CEQA has periodically
drawn the attention of the state legislature, most recently in 1993, when over 60 CEQA reform bills were introduced. This
paper describes the CEQA process and evaluates its success at meeting its explicit and implicit goals. The research includes
a statewide survey of CEQA practice, sent to the planning departments of all 513 local governments in California in 1991.
Survey respondents agreed that CEQA helps in evaluating environmental impacts, reducing impacts, informing the public, and
coordinating public agency review. It is effective in reducing the environmental impacts of individual projects, but is not
as effective in improving environmental quality on an areawide scale. This research concludes that CEQA has led to positive
outcomes and is not as deeply flawed as many of its critics claim. Still, CEQA as currently designed may not be the optimal
vehicle for ensuring environmental quality. 相似文献
273.
The diagram constructed for selection of sampling methods indicates that, for a systematic error, E ≤ 13%, grab sampling (GS) may be used to characterize effluents with variation coefficient of flow ≤ 120% and of contaminant concentrations ≤ 10%. For the whole studied range of variation coefficient of contaminant concentrations (2–82%), time-proportional compositing (TC) method may be applied with E ≤ 10% for effluents characterized by variation coefficients in flow < 90%. The more complicated flow-proportional compositing (FC) method is required only for effluents with larger variation coefficients or to produce more precise results. The diagram constructed for selection of sampling frequencies indicates that sequential sampling at intervals of approximately 60 min may be applied with E ≤ 10% for effluents characterized by variation coefficients ≤ 30%. Practical application of the diagrams, constructed using normal series, was checked against monitoring data from two pulp and paper mills in Vietnam. The two diagrams provided results on sampling methods and frequencies in good agreement with those obtained from actual monitoring data with percentages of agreement cases of 80 and 75%, respectively. The approach was applied in design of a monitoring program at the Bai Bang integrated pulp and paper mill in Vietnam. 相似文献
274.
275.
用氯离子选择电极法测定油田废水中氯化物是一种新方法。通过电极响应平衡速度试验、干扰消除试验、方法适应性试验等,探讨了温度对能斯特斜率的影响;PH对测定值的影响;总离子强度调节缓冲溶液(TISAB)的选择。本方法分析速度快,测定浓度范围宽,操作简便,成本低,值得推广。 相似文献
276.
运用地图学的理论和方法,阐述了灾害地图的性质、内容、功能和作用,介绍了灾害地图的主要类型,探讨了灾害信息图形显示的过程、方法和手段,并提出了开展灾害地图研究的几点建议。 相似文献
277.
TOPHAZOP: a knowledge-based software tool for conducting HAZOP in a rapid, efficient yet inexpensive manner 总被引:3,自引:0,他引:3
Faisal I. Khan S. A. Abbasi 《Journal of Loss Prevention in the Process Industries》1997,10(5-6):333-343
Hazard and operability (HAZOP) studies constitute an essential step in the risk analysis of any chemical process industry and involve systematic identification of every conceivable abnormal process deviation, its causes and abnormal consequences. These authors have recently proposed optHAZOP as an alternative procedure for conducting HAZOP studies in a shorter span of time than taken by conventional HAZOP procedure, with greater accuracy and effectiveness [Khan, F. I. and Abassi, S. A., optHAZOP. An effective and efficient technique for hazard identification and assessment Journal of Loss Prevention in the Process Industries, 1997, 10, 191–204]. optHAZOP consists of several steps, the most crucial one requires use of a knowledge-based software tool which would significantly reduce the requirement of expert man-hours and speed up the work of the study team. TOPHAZOP (Tool for OPTmizing HAZOP) has been developed to fulfil this need.
The TOPHAZOP knowledge-base consists of two main branches: process-specific and general. The TOPHAZOP framework allows these two branches to interact during the analysis to address the process-specific aspects of HAZOP analysis while maintaining the generality of the system. The system is open-ended and modular in structure to make easy implementation and/or expansion of knowledge. The important features of TOPHAZOP and its performance on an industrial case study are described. 相似文献
278.
通过对变流量冷冻水系统的分析指出,在运用平衡调温调湿方式的空调系统中,应用变流量冷冻水系统可以较大地节约能源和投资;并提出了实现这种应用的方法。 相似文献
279.
对火工品可靠性(或安全性)评估中通常采用的经典方法进行了剖析。介绍了数理统计方法学中近年来兴起的Bayes统计推断方法,并给出了此法在火工品二项分布、正态分布情况下,对可靠度评估的应用实例。 相似文献
280.
高浓度酒精糟液经厌氧生物处理后排出的消化液COD浓度为4500—6000mg/L,SS浓度高这1500—2.600mg,/L,且由于微小沼气泡附着在厌氧污泥上,沉降性能很差,难以与消化液相分离,对后续处理十分不剁。本研兜采用预曝气.化学混凝沉淀组合工艺,对该消化液进行去除高浓度SS的顸处理试验,研究探讨了曝气时间、混凝剂种类和投加量对SS和COD去除效果的影响。试验结果表明,预曝气.化学混凝沉淀组合工艺对消化液SS的去除效果十分显著。当预曝气时间为6.0h,FeCl3投加量为100mg/L时,消化液的SS去除率75.4%,COD去除率24.3%,可为后续的好氧生物处理提供较为有利的水质和负荷条件。 相似文献