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941.
化学物质可能对生态环境或通过不同环境介质对人体健康造成危害。为识别出高危害的污染物,采用Copeland计分排序法和证据权重法,分别选择4、6和8个筛选指标,开展了50种污染物危害特性优先性排序。结果表明:筛选因子数量相同时,2种方法危害性排序结果的斯皮尔曼相关性在0.94以上,具有较好的相关性,可见2种方法均可用于污染物危害性排序;方法相同时,不同指标排序结果之间的相关性相对较小,表明选择不同的筛选指标对结果影响较大。  相似文献   
942.
近年来,海洋和淡水环境中微塑料污染已成为全球关注的热点问题。微塑料不仅会对生物体造成物理损伤,而且微塑料会吸附环境中的疏水性有机污染物(HOCs),也能释放其本身含有的添加型疏水性有机化合物至表面,从而形成复合污染物进入生物体。然而,有关微塑料在污染物生物富集过程中发挥的作用及其机制还不清楚。本文从实验室暴露、野外富集和模型模拟研究3个方面对微塑料作用下HOCs的生物富集规律进行了综述,总结了微塑料作用下的生物富集机制。最后,针对微塑料对HOCs生物富集作用的研究方向提出了几点建议。  相似文献   
943.
Air monitoring stations were set up at 2 sites in the southern hemisphere--Moody Brook, Falkland Island (51 degrees 25' S, 57 degrees 56' W) and Halley, Research Station, Antarctica (75 degrees 35' S, 26 degrees 30' W). PCBs were monitored at the stations throughout 1999. Highest concentrations were observed when temperatures were greater. In general, concentrations were greater at Moody Brook than at Halley, although the difference in concentrations between sites was less for more chlorinated congeners. Air concentrations at both sites were compared with samples collected nearby over-water. Over water air concentrations were found to be greater than over land air concentrations. Concentrations were also compared with literature data for air concentrations at a remote site in the Canadian Arctic. Atmospheric concentrations of tri-chlorinated biphenyls were found to be approximately double those reported for Ellesmere Island in the Canadian Arctic, whilst concentrations in samples from Antarctica were very similar to those found in the high Arctic. Most other PCBs were a factor of 2-4 greater in the Canadian Arctic.  相似文献   
944.
Members of the United Nations Economic Commission for Europe (UN-ECE) signed a legally binding protocol on persistent organic pollutants (POPs) in February 1998 under the Convention on Long-Range Transboundary Air Pollution. A treaty that intends to control the production, import, export, disposal and use of toxic chemicals that persist for decades in the environment has been formally signed at a conference in May 2001 in Stockholm. The 2001 POP treaty, like the 1998 LRTAP POP protocol, contains a provision on adding further chemicals to the initial group of twelve or fifteen. The occurrence of a compound or a group of compounds in so called remote and pristine areas, e.g. in the Artic or in the Southern Hemisphere, proves its stability under the chemical and biological conditions of the environment. Compounds identified in this way, in samples taken primarily in very remote regions of the planet, are classified by their environmental fate and global distribution as persistent organic pollutants (POPs), regardless of any political assessments.  相似文献   
945.
ABSTRACT: Linear programming is applied to identify the least cost strategy for reaching politically specified phosphorus and total suspended solids reduction targets for the Fox-Wolf river basin in Northeast Wisconsin. The programming model uses data collected on annualized unit reduction costs associated with five categories of sources of phosphorus and total suspended solids discharge in each of the 41 sub-watersheds in the basin to determine the least cost management strategy. Results indicate that: (1) cost-effective nutrient reduction requires careful selection of geographic areas and source categories to address throughout the watershed; (2) agricultural sources are the most cost-effective to address in the basin; and (3) care should be exercised in setting nutrient reduction targets, given that there are likely to be significantly increasing marginal costs of nutrient reduction; the model predicts that lowering the most restrictive target by 33 percent would cut reduction expenditures by about 75 percent. Policy implications of the model include support for the investigation and potential development of institutional arrangements that enable cost-effective nutrient reduction activities to occur, such as the creation of an agency with authority over a given watershed, coordinated watershed management activities, or nutrient trading programs.  相似文献   
946.
ABSTRACT: Public Law 92–00 has mandated the need for evaluating the impact of nonpoint source pollution on receiving water quality, primarily through Section 208 Areawide Planning. The Management of Urban Non-Point Pollution (MUNP) model was developed to estimate the accumulation of eight non-point pollutants on urban streets, their removal by both rainfall and street sweeping operations. The model can simulate the following pollutants: total solids or sediment-like material, volatile solids, five-day biochemical oxygen demand, chemical oxygen demand, Kjeldahl nitrogen, nitrates, phosphates, and total heavy metals. The simulated results can be used for investigation of non-point pollution management alternatives. The model is capable of reflecting variation in such diverse factors as physical and chemical characteristics of accumulated pollutants, land use characteristics, rainfall characteristics, street sweeper characteristics, roadway characteristics, and traffic conditions. By using mean estimates of many input variables for large segments of a city, the MUNP model could be used to quickly assess the magnitude of pollutants annually entering receiving waterways due to nonpoint source pollution alone. If the results indicate that non-point pollution loadings are sizeable and require futher analysis, the MUNP model could be used to define the specific nonpoint source pollution areas within a city. Hypothetical locations and actual rainfall data for Washigton D.C. were used to demonstrate some capabilities of the MUNP model.  相似文献   
947.
ABSTRACT: Arizona's water pollution control program is based on authorties of Arizona Revised Statutes and Public Law 92–500, the Federal Water Pollution Control Act Amendments of 1972. The primary areas of this program are monitoring, facility inspections, plan review, planning, discharge permits and grants for the construction of publicly-owned waste water treatment facilities. The discharge permit program deals with control of point-source discharges and is administered by the United States Environmental Protection Agency. The planning and construction grants programs are administered by the State Water Quality Control Council and are implemented by the Bureau of Water Quality Control, which serves as staff to the Council. There are several challenges that face the State in this program. First is the adaptation of the “eastern law” to deal with Arizona's water quality problems. Second is to address problems caused by a long history of “laissez-faire” environmental quality management. Third is a mutual cooperation and coordination among the many entities involved in water resources management. Areas of particular interest in the State's program is the process setting water quality standards and the involvement of people of diversified backgrounds in the field of areawide planning under Section 208 of the Federal Water Pollution Control Act, which is primarily concerned with non-point sources of water pollution.  相似文献   
948.
ABSTRACT: The current 201 study by the Bergen County Sewer Authority illustrates possibilities for improving the currently defined relationships between 201, 208 and 303 studies. The Bergen County Sewer Authority serves 115 square miles in northeast New Jersey, providing sewerage service to 507,000 people in 43 municipalities. Its STP discharges to the Hackensack River, a tidal estuary recently classified as Water Quality Limited, and which receives significant non-plant loading. The subject 201 study is concurrent with 208 and 303 planning by NJDEP. Preliminary evaluations show that detailed 201 work can affect the conclusions of 303 and 208 studies, and that a wider (environmental - social as well as economic) interpretation of cost-effectiveness can demand re-examination of prior assumptions and decisions, a task not typically part of 208–303 work. Increased flexibility is needed in applying 303 and 208 recommendations to defining 201 studies and NPDES permit criteria, particularly in analysis of water use objectives, water quality parameters and future flows, loadings and facility costs. Further, perception of alternatives can be clarified by broadening analysis of costs and control and plant strategies. Inclusion of 201 planning at all stages of regional planning can synergistically improve the total planning process.  相似文献   
949.
This article presents a short overview of selected recent papers using nuclear magnetic resonance (NMR) to investigate interactions between organic pollutants and soil components such as organic matter, clays, whole soils, and sediments. First, we describe solid state cross polarisation magic angle spinning (CP-MAS) experiments as the main tools to investigate covalent bonds. Second, we report NMR approaches allowing us to assess molecule mobility and to characterise non-covalent interactions. Those approaches include correlations between K oc values and soil organic matter functions determined by CP-MAS, 2H NMR fingerprints, relaxation time measurements, 19F and 1H high resolution (HR)-MAS experiments.  相似文献   
950.
NOx污染控制进展   总被引:2,自引:0,他引:2  
本文概述了近年来国内外NOx污染控制的进展,并介绍了将一种矿石原料打成浆料,在低温下吸收NOx,吸收后得一种很有经济价值的硝酸盐,此硝酸盐可直接作为产品销售出去,也可进一步加工成一种高附加值产品的研究成果。  相似文献   
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