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181.
182.
气相和颗粒物中邻苯二甲酸酯的采样与检测技术 总被引:2,自引:0,他引:2
对邻苯二甲酸酯的性质及其在环境空气中的存在状态、样品采集技术与分析方法进行了综述,侧重介绍了样品的采集、净化、采样效率和采样与分析全过程的质量控制。 相似文献
183.
Prasanta Kumar Dey 《Environmental Impact Assessment Review》2002,22(6):509
The cross-country petroleum pipelines are environmentally sensitive because they traverse through varied terrain covering crop fields, forests, rivers, populated areas, desert, hills and offshore. Any malfunction of these pipelines may cause devastating effect on the environment. Hence, the pipeline operators plan and design pipelines projects with sufficient consideration of environment and social aspects along with the technological alternatives. Traditionally, in project appraisal, optimum technical alternative is selected using financial analysis. Impact assessments (IA) are then carried out to justify the selection and subsequent statutory approval. However, the IAs often suggest alternative sites and/or alternate technology and implementation methodology, resulting in revision of entire technical and financial analysis. This study addresses the above issues by developing an integrated framework for project feasibility analysis with the application of analytic hierarchy process (AHP), a multiple attribute decision-making technique. The model considers technical analysis (TA), socioeconomic IA (SEIA) and environmental IA (EIA) in an integrated framework to select the best project from a few alternative feasible projects. Subsequent financial analysis then justifies the selection. The entire methodology has been explained here through a case application on cross-country petroleum pipeline project in India. 相似文献
184.
A. M. Cicero M. Mecozzi R. Morlino D. Pellegrini E. Veschetti 《Environmental monitoring and assessment》2001,71(3):297-316
Dredging is a very important procedure for harbor management. InItaly the guidelines for the offshore dumping of dredged materials are issued by the Ministry of Environment. Theydescribed a few steps of dredging activities, such as thesampling strategy, but do not deal with limits or guide-valuesfor the chemical, physical and biological composition of theresulting sediments. The quality of dredged materials is mainlydependent on the presence of inorganic and organic pollutants.In particular, polychlorinated biphenyls (PCBs) and organo-chlorinated pesticides are seen as a high priority inmarine environment by international organizations because oftheir persistence, toxicity and bioaccumulation capacity.In this article the presence of some PCBs and organo-chlorinatedpesticides in sediment samples collected from the harbor ofLivorno (Northern Tyrrhenian Sea) was investigated. Theconcentration of HCHs, Aldrin, Chlordanes, DDEs, DDTs, and PCBsin 12 representative sites ranged between <1 g kg–1and 95, 19, 32, 35, 107, and 111 g kg–1, respectively.The application of univariate and multivariate statisticaltechniques, such as linear regression analysis and principalcomponent analysis, to the experimental data showed a differentdistribution of PCBs in the two sediment layers. On thecontrary, the vertical distribution of the other investigatedpollutants was more homogeneous and affected by randomvariability. The multivariate approach was an important tool to establish more rational criteria for the management of dredged materials. 相似文献
185.
Yu.M. Svirezhev W. von Bloh H.-J. Schellnhuber 《Environmental Modeling and Assessment》1999,4(4):287-294
A novel approach to the problem of estimating climate impact on social systems is suggested. This approach is based on a risk concept, where the notion of critical events is introduced and the probability of such events is estimated. The estimation considers both the inherent stochasticity of climatic processes and the artificial stochasticity of climate predictions due to scientific uncertainties. The method is worked out in some detail for the regional problem of crop production and the risks associated with global climate change, and illustrated by a case study (Kursk region of the FSU). In order to get local climatic characteristics (weather), a so-called statistical weather generator is used. One interesting finding is that the 3% risk level remains constant up to 1.0–1.1°C rise of mean seasonal temperature, if the variance does not change. On the other hand, the risk grows rapidly with increasing variance (even if the mean temperature rises very slowly). The risk approach is able to separate two problems: (i) assessment of global change impact, and (ii) decision making. The main task for the scientific community is to provide the politicians with different options; the choice of admissible (from the social point of view) critical events and the corresponding risk levels is the business of decision makers. 相似文献
186.
We propose a modelling framework for the design of a Pigouvian effluent tax, in an environmental management problem implicating
several economic agents located in a river basin. The proposed charging system allows for the agents' geographical position
relative to the river's sections, at which environmental standards are to be enforced, and takes into account the possible
different market structures within which the agents are operating. In particular, we consider industrial agents competing
on an oligopolistic market, and a set of farmers acting as price takers on a large market. A regional authority's goal is
to induce agents to some sort of cooperation which would result in the satisfaction of the common environmental constraints.
The economic process on one side, and the pollution transport and accumulation on the other, constitute two dynamic processes
in two different time scales. As the economic process is much slower than the other process we can neglect the latter's transients
and concentrate on the time invariant steady state solutions to the transportation equation. The model thus constructed has
some noncooperative game and optimal control problem's features with space being the ‘running’ variable.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
187.
用工业废水排放量预测地面水CODMn灰色方法研究 总被引:2,自引:0,他引:2
GPM(1)灰色生长曲线常被用于等距时序环境系统的分析建模、非等距摆动空间序列方面的应用尚未报道。本文研究提出了将非等距摆动空间序列经过等距化处理的GPM(1)线性回归优化建模方法采用该方法所建的非等距GPM(1)模型用于工业废水量预测地面水CODMn的实例表明,该方法简捷,方便、精度高于回归分析,有较大实用价值。 相似文献
188.
工作场所空气中硫酸雾(SO3)的分析 总被引:1,自引:0,他引:1
王连弟 《环境监测管理与技术》1997,9(3):36-37
采用碘量法测定工作场所空气中的三氧化硫及硫酸雾,三氧化硫及硫酸雾经中性水吸收后与碘化钾和碘酸钾反应,析出的碘与淀粉指示剂作用产生蓝色,进行比色测定。 相似文献
189.
共振光散射技术是一项在普通荧光分光光度计上进行测量的光散射技术,文章简要介绍了光散射现象,共振光散射的基本原理并作了定量基础讨论,对共振光散射技术在环境分析中的应用作了初步研究。 相似文献
190.