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141.
142.
The EMAP model (Eulerian Model for Air Pollution) is applied for calculating the sulfur concentration and deposition fields for 1995 as based upon Bulgarian and Greek sources. The country-to-country budgets show that about 4% of the sulfur oxides emitted by Bulgaria are deposited over Greek territory, estimated at 28 kt S. Only 2% of sulfur compounds emitted by Greece are deposited over Bulgaria, estimated at 6.2 kt S for 1995. This data is in agreement with EMEP/MSC-W estimates and provides more details concerning time and space. The results can be used in decision-making, negotiating and the development of contamination strategies.  相似文献   
143.
Santiago, Chile has the distinction of having among the worst urban air pollution problems in Latin America. As part of an atmospheric pollution reduction plan, the Santiago Regional Metropolitan government defined an environmental policy goal of using urban forests to remove particulate matter less than 10 microm (PM(10)) in the Gran Santiago area. We used cost effectiveness, or the process of establishing costs and selecting least cost alternatives for obtaining a defined policy goal of PM(10) removal, to analyze this policy goal. For this study, we quantified PM(10) removal by Santiago's urban forests based on socioeconomic strata and using field and real-time pollution and climate data via a dry deposition urban forest effects model. Municipal urban forest management costs were estimated using management cost surveys and Chilean Ministry of Planning and Cooperation documents. Results indicate that managing municipal urban forests (trees, shrubs, and grass whose management is under the jurisdiction of Santiago's 36 municipalities) to remove PM(10) was a cost-effective policy for abating PM(10) based on criteria set by the World Bank. In addition, we compared the cost effectiveness of managing municipal urban forests and street trees to other control policies (e.g. alternative fuels) to abate PM(10) in Santiago and determined that municipal urban forest management efficiency was similar to these other air quality improvement measures.  相似文献   
144.
A review of ozone pollution in Italy shows levels largely above the thresholds established by EU regulation for vegetation and human health protection. The Italian air quality monitoring network appears quantitatively inadequate to cover all the territorial surface, because of scarcity and unequal distribution of monitoring sites. By applying the integrated assessment model RAINS-Italy to the year 2000, the whole of Italy exceeds the AOT40 critical level for forest, while Northern and central areas show strong potential of O3 impact on human health with ∼11% of territory >10 O3-induced premature deaths. Two scenarios for the year 2020, the Current Legislation and the Maximum Technical Feasible Reduction, show a reduction of AOT40Forest by 29% and 44%, SOMO35 by 31% and 47%, and O3-induced premature deaths by 32% and 48%, compared to 2000. RAINS-Italy can be used to improve the map quality and cover areas not reached by the national monitoring network.  相似文献   
145.
The analysis of three years of 8-h CO concentration values registered in a deep street canyon downtown shows high frequency of values that exceed WHO health protection guidelines. An inverse relationship between opposing percentiles of the distributions of CO concentrations and mean wind speed could be found. Data also showed a variation of mean CO values with prevailing wind direction. The averaged concentration value obtained when the sampler probe is on the leeward side is lower than the obtained when it is on the windward wall. A preliminary explanation of this feature may be related to the advection of polluted air from a high traffic density area nearby.  相似文献   
146.
To estimate air pollution snow samples were collected in March 2001 at six sites in the vicinity of the Kostomuksha factory in Karelia. Seventy-two chemical elements and more than 200 individual organic compounds were identified by inductively coupled plasma mass spectrometry (ICP-MS) and gas chromatography mass spectrometry (GC-MS). It was found that the levels of Li, B, Al, Fe, Ni, Cu, Zn, Hg, Mn, Mo as well as hydrocarbons, phthalates and phenols exceeded the existing maximum allowable concentrations. A list of toxicants emitted with the factory exhausts and a list of priority pollutants for Kostomuksha were compiled. The impact of the exhausts of the Kostomuksha factory on the environment in Finland is relatively small. Electronic Publication  相似文献   
147.
结合江苏省“十一五”期间环境质量状况及变化情况,综合分析了环境空气、水环境、声环境质量及污染物排放状况.“十一五”期间,江苏省经济总量以13.5%的平均速度增长,社会、经济的快速发展给全省环境质量带来巨大的胁迫压力,资源能源消耗迅速攀升,“三废”产生总量持续增长;而由于加大了节能减排和环境治理投入力度,采取了一系列措施...  相似文献   
148.
The Canoparmelia texana epiphytic lichenized fungi was used to monitor atmospheric pollution in the S?o Paulo metropolitan region, SP, Brazil. The cluster analysis applied to the element concentration values confirmed the site groups of different levels of pollution due to industrial and vehicular emissions. In the distribution maps of element concentrations, higher concentrations of Ba and Mn were observed in the vicinity of industries and of a petrochemical complex. The highest concentration of Co found in lichens from the S?o Miguel Paulista site is due to the emissions from a metallurgical processing plant that produces this element. For Br and Zn, the highest concentrations could be associated both to vehicular and industrial emissions. Exploratory analyses revealed that the accumulation of toxic elements in C. texana may be of use in evaluating the human risk of cardiopulmonary mortality due to prolonged exposure to ambient levels of air pollution.  相似文献   
149.
傅尧信  杨柳 《四川环境》2008,27(1):102-106
近年来,人们越来越关注车内空气污染。但人们对车内空气污染的了解甚少。本文就车内空气污染的污染源、污染物、健康影响、治理措施,相关标准等一系列问题,作系统论述。  相似文献   
150.
H-酸的催化湿式氧化反应过程研究   总被引:9,自引:0,他引:9  
湿式氧化(WAO)和催化湿式氧化(CWAO)都能有效地处理染料中间体--H-酸。所有的H-酸在5min内均被支除和形成一些中间产物。在不同反应时间段测定了pH值及阴、阳离子和小分子有机酸等中间产物。分析表明,pH值与COD的去除及有机酸的产生有密切的联系,H-酸被氧化成NH4^+、SO4^2-、HCOOH和CH2COOH。WAO法的瓜速率慢而且氧化乙酸困难。而CWAO法的反应速率不但快而且能有效地  相似文献   
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