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731.
本文通过对沈阳市噪声环境污染存在问题的评价分析,探讨构建以噪声功能区划、污染监控体系,污染防治体系,公众参与体系和法律、法规和标准体系等为主要内容的噪声污染防治技术支撑体系的框架和机制,进而达到改善声环境质量的目的。 相似文献
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733.
本文对呼和浩特市空气环境质量现况进行了科学地评价,并且分析了污染原因,在此基础上给出了相应的综合治理措施。 相似文献
734.
异相催化是催化反应的重要组成部分,其应用十分广泛。固一液异相催化作为环境科学领域中的一项比较新颖的技术,在研究污染物在多介质环境中的迁移转化行为、开发受污染环境修复及污废水处理新技术等诸多方面都具有很大的发展潜力。因此,对不同类型固一液异相催化剂在环境科学领域的应用研究逐渐成为国内外环境科学领域的研究热点之一。其中,金属和金属氧化物因对某些氧化一还原反应具有较好的催化作用,在饮用水脱氮、污废水脱卤及深度氧化处理等水处理领域的应用较为广泛;固态酸催化剂能催化聚合、裂化、水解反应,因此与某些有机污染物的降解密切相关;将同相催化剂固定化为异相催化剂,同样成为新技术开发的方向之一;天然催化剂对污染物在多介质环境中行为影响的研究近年来也屡有发表。此外,载体因对催化剂的活性及应用具有重要影响,也日益受到关注。文章对环境科学领域中固一液异相催化剂的应用研究进行了综述。 相似文献
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736.
城市是由于人-地剧烈相互作用而形成的开放的、复杂的社会、经济与环境复合巨系统,在城市环境规划工作中常伴随有大量的结构化、半结构化和非结构化并存的决策问题,这就需要采取人—机交互式的决策支持系统方法来全面支持规划专家的规划活动,同时,城市环境规划本身也是个面向空间实体的操作过程,这也决定了GIS将发挥基础性主导工具作用,基于以上两点认识,作者以GIS为基本框架,设计了城市环境规划的空间决策支持系统原型方法,实现了城市环境规划数据调查评价、预测、功能区划、规划方案生成与决策、制图等特定功能要求,成为支持城市环境规划的有力工具。 相似文献
737.
Abundance vector estimation is a well investigated problem in statistical ecology. The use of simple random sampling with replacement or replicated sampling ensures good asymptotic properties of the abundance vector estimators. However, real surveys are based on small sample sizes, and assuming any specific distribution of the abundance vector estimator may be hazardous.In this paper we focus our attention on situations where the population is not too large and the sample size is small. We propose bootstrap multivariate confidence regions based on data depth. Data depth is a geometrical concept of ordering data from the center outwardly in higher dimensions. The Simplicial depth, the Tukey's depth and the Mahalanobis depth are presented. In order to build confidence regions in the presence of a skewed distribution of the abundance vector estimator, the use of Tukey's depth is suggested. The proposed method has been applied to the benthic community of Lake Lesina. A comparison with Mahalanobis depth and standard existing methods is reported. 相似文献
738.
甲基对硫磷降解菌GFP标记菌株的构建 总被引:4,自引:1,他引:4
用Sau3AⅠ酶切甲基对硫磷降解菌DLL 1总DNA ,与BamHⅠ酶切的启动子探针载体 pRobe -GFP酶连 ,转化E .coliDH5α ,在选择性平板LB(Ampr)上从大约 1× 10 4个菌落筛选到 5 0个含启动子片断的阳性克隆 .挑选其中一个阳性克隆 ,将启动子片断克隆到pIJ2 92 5和 pBBR -MCS2上构建成重组质粒 pIJGFP和广宿主标记载体pB BRGFP .然后将 pIJGFP载体上的启动子片断克隆到广宿主载体 pTR10 2上 ,获得第二个广宿主标记载体pTRGFP .将pTRGFP和pBBRGFP通过三亲接合分别标记于DLL 1得到两株标记菌 ,即DLLTR和DLLBR .通过激光共聚焦显微镜观察和软件Lasersharpversion 3.2分析发现 pTRGFP在E .coli中表达很强而在DLL 1中表达很弱 ,而 pBBRGFP正好相反 .图 5表 2参 12 相似文献
739.
Ernest M. Thiessen Daniel P. Loucks 《Journal of the American Water Resources Association》1992,28(1):163-177
ABSTRACT: Since the early 1970s, a large volume of literature has accumulated related to multiobjective water resources management problems. A relatively small portion of this specifically addresses the negotiation process required when there are multiple decision makers with conflicting objectives. This paper focuses on that process and describes a computer program designed to assist such negotiation processes. This interactive computer assisted negotiation support system is called ICANS. ICANS is designed for dynamic, multi-issue, multi-party negotiation problems. Based on information provided in confidence by each party via an interactive graphical interface, the program can help determine if there exist any possible alternatives that are equivalent or even preferred to each party's decision in the absence of a negotiated agreement. If such alternatives exist, through a series of iterations in which each party's input data, assumptions, and preferences may change, ICANS can assist the parties in their search for a mutually acceptable and preferred agreement. A simple example illustrates the data requirements and the use of ICANS in negotiation experiments. 相似文献
740.
Dina E. Flockhart Chi Ho Sham Yan Xiao 《Journal of the American Water Resources Association》1993,29(6):957-964
ABSTRACT: Public awareness of the importance of protecting the nation's water supplies is growing. Recent studies have shown a substantial increase in the perceived value of protecting water supplies for future use. In the Northeast, much of the water supply comes from ground water. This paper examines three test cases, each with different approaches for using geographic information systems (GIS) for ground water protection planning. In Wellfleet, Massachusetts, build-out scenarios were used to support regulatory and land acquisition decisions for siting a public water supply well. In Hadley, Massachusetts, the focus was on a decision support model for septic suitability assessment in support of regulatory efforts and infrastructure expansion. For Cortland County, New York, an interactive graphic user interface was created to facilitate the manipulation and recombination of a large volume of data by county officials to target ground water pollution prevention efforts. As personal computers become more powerful and inexpensive, and GIS data become more readily available, community and county governments are turning to GIS as a tool for developing comprehensive resource protection plans. Once appropriate data are input, a GIS can effectively and efficiently be used to derive outcomes of various land use plans and regulations. 相似文献