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141.
离子色谱法同时测定有机和无机阴离子   总被引:2,自引:0,他引:2  
胡枢  魏春良 《上海环境科学》1997,16(2):30-31,41
用离子色谱法同时测定有机阴离子和无机阴离子,实验中采用一种新型高容量分离柱,灵敏度高,选择性好。讨论了最佳实验条件的选择测定了F^-,Cl^-,SO4^2-,NO2^-,SeO3^2-、C2O4^2-、甲酸奶和乙酸根等阴离子,并且分析了沈阳地区雪样中的几种阴离子。  相似文献   
142.
司蔚 《环境科技》2003,16(4):35-36
对1996~2002年江苏省城市噪声源的构成以及道路交通污染状况和变化趋势进行了评析,指出在城市机动车拥有量不断增长的情况下,全省城市道路交通噪声总体达标,且呈现下降趋势。但仍要对部分污染较重的超标路段加强控制。  相似文献   
143.
介绍“双膜法”工艺的流程及运行情况,并对影响装置稳定运行的因素进行分析,提出建议。  相似文献   
144.
Sampling and physico-chemical analysis of precipitation: a review   总被引:2,自引:0,他引:2  
Wet deposition is one of two processes governing the transfer of beneficial and toxic chemicals from the atmosphere on to surfaces. Since the early 1970s, numerous investigators have sampled and analyzed precipitation for their chemical constituents, in the context of "acidic rain" and related atmospheric processes. Since then, significant advances have been made in our understanding of how to sample rain, cloud and fog water to preserve their physico-chemical integrity prior to analyses. Since the 1970s large-scale precipitation sampling networks have been in operation to broadly address regional and multi-regional issues. However, in examining the results from such efforts at a site-specific level, concerns have been raised about the accuracy and precision of the information gathered. There is mounting evidence to demonstrate the instability of precipitation samples (e.g. with N species) that have been subjected to prolonged ambient or field conditions. At the present time precipitation sampling procedures allow unrefrigerated or refrigerated collection of wet deposition from individual events, sequential fractions within events, in situ continuous chemical analyses in the field and even sampling of single or individual rain, cloud and fog droplets. Similarly analytical procedures of precipitation composition have advanced from time-consuming methods to rapid and simultaneous analyses of major anions and cations, from bulk samples to single droplets. For example, analytical techniques have evolved from colorimetry to ion chromatography to capillary electrophoresis. Overall, these advances allow a better understanding of heterogeneous reactions and atmospheric pollutant scavenging processes by precipitation. In addition, from an environmental perspective, these advances allow better quantification of semi-labile (e.g. NH4+, frequently its deposition values are underestimated) or labile species [e.g. S (IV)] in precipitation and measurements of toxic chemicals such as Hg and PCBs (polychlorinated biphenyls). Similarly, methods now exist for source-receptor studies, using for example, the characterization of reduced elemental states and/or the use of stable isotopes in precipitation as tracers. Future studies on the relationship between atmospheric deposition and environmental impacts must exploit these advances. This review provides a comprehensive and comparative treatment of the state of the art sampling methods of precipitation and its physico-chemical analysis.  相似文献   
145.
The present study was intended to establish an inventory of PCDD/F emissions in Tarragona Province (Catalonia, NE Spain), as a preliminary phase in the development of a flow analysis of PCDD/Fs in this Province. In 1999, global PCDD/F emissions reached a value of 2.24 g I-TEQ/y, which means a density of 3.8 micrograms I-TEQ/inhabitant/y. The low amount of PCDD/Fs emitted to air by the only municipal solid waste incinerator in the Province (approximately 0.04% of the total) has been one of the most notable results. As a reflection of uncertainties in the estimates for individual sources, the 90th percentiles of PCDD/F releases for 1999 ranged up to 4.1 g I-TEQ/y.  相似文献   
146.
珠江三角洲典型区景观生态聚类分析   总被引:7,自引:2,他引:7  
珠海是珠江三角洲地区一个海陆交互作用与人类干扰活动频繁的典型区域。文章以2000年TM数据为基础数据源,编制珠海地区景观类型图,并以镇(区)为基本空间单元将珠海划分为20个景观生态子区,在GIS与景观斑块分析软件Patch Analyst 2.0支持下计算各子区的景观特征指数。通过各子区的景观指数对比分析,探讨研究区范围内景观格局的空间差异,揭示人类活动、自然干扰等各种景观生态机制对区域景观生态的影响。根据各指数反映的景观特征信息,选择平均斑块大小(MPS)、斑块大小变异系数(PSCOV)、边缘密度(ED)、面积加权分维数(AWMPFD)、破碎度指数(F)、多样性指数(SDI)及人为干扰指数(DT)进行珠海景观生态聚类分析,根据聚类分析结果可多层次客观地对珠海地区进行景观生态类型区划分。  相似文献   
147.
In evaluating current environmental protection policy, economists often note that current regulations are more costly than necessary to meet environmental quality standards. While the a priori case is strong that current regulatory approaches are resulting in higher-than-necessary costs to attain environmental standards, there is relatively little empirical evidence to support this claim. The purpose of this paper is to supply some of the missing evidence by presenting the results of one study that assesses some of the potential savings associated with implementing economic, rather than command-and-control, regulatory approaches to abate one type of air pollution in one region of the country. Specifically, the paper examines the costs of meeting a prospective short-term standard for nitrogen dioxide under a range of alternative emissions control strategies for stationary sources of nitrogen oxide emissions in the Chicago Air Quality Control Region. The alternative strategies that are considered range from those that might result under current regulatory policy to those that economic policy approaches (such as emissions charges or marketable permits) are designed to implement. The analysis shows that the most efficient program of emissions controls may be more than an order of magnitude less costly than current regulatory strategies, and that economic approaches have additional advantages over more conventional regulatory approaches.  相似文献   
148.
从实验室建设和人员培训两个方面,论述了开展恶臭监测分析所必须建立的基础设施和条件,特别就有关特殊的技术要求和要点问题进行了介绍.  相似文献   
149.
太原市大气污染特征分析及其防治   总被引:2,自引:0,他引:2  
以太原市近 5年的大气环境监测数据为基础 ,评价了大气环境质量现状 ,详细论述了大气污染特征及其产生的原因 ,并针对大气环境存在的主要问题 ,提出了市区大气污染防治对策。  相似文献   
150.
高层建筑可预期的灾变非至一端,这里仅探讨高层建筑的抗震性能问题。地震过程中楼体受到的是地震波和自身固有频率的共同作用,此时楼体是一个多维动态系统,其应力状态比传统方法所描述的力学模型要复杂行多。本文应用ANSYS三维仿真有限元软件,采用单点响应谱的方法,对楼体在纵向地震波作用下的应力状态和变形情况进行了分析。对楼体构件单元型式的选择、网格密度的确定、有限元模型的建立等也提出了自己的见解。在后处理中,用列表和图形的方式显示了楼体的位移和应用状态。  相似文献   
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