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911.
The need to determine cost estimates of the hazardous effects of diseases is important in order to establish the priorities of actions for prevention and health management. The evaluation of air pollution impacts on health, based on expenditures, has been carried out, but there are obvious comparison difficulties among countries, as the health-per-capita investment varies enormously. In order to achieve a standard indicator, we applied the Disability-Adjusted Life Years (DALY) method to estimate the health burden and cost estimate due to air pollution in São Paulo, Brazil. The basic methodology was the utilization of dose–response curves of epidemiological studies conducted in São Paulo to assess air pollution and its health effects. DALY attributable to air pollution in São Paulo added up to 28,212 years annually. An indirect health cost attributable to air pollution resulted in US$ 3,222,676. This estimate refers to the children and the elderly population. These results give a preliminary and underestimated value of the burden of diseases promoted by air pollution. 相似文献
912.
Can China control the side effects of motor vehicle growth? 总被引:2,自引:0,他引:2
Michael P. Walsh 《Natural resources forum》2007,31(1):21-34
Motor vehicle growth in China is the fastest in the world. This is placing great strain on the urban environment and causing a rapid increase in oil imports and motor vehicle carbon dioxide emissions. To deal with the environmental and health effects of air pollution, China has adopted a strong motor vehicle pollution control programme and imposed limits on fuel consumption of new light duty vehicles. The article will review these problems and programmes. Special focus will be given to the need to reduce sulphur levels in both gasoline and diesel fuel. 相似文献
913.
Various air pollution control (APC) techniques were employed in order to reduce emissions of air pollutants produced from
chemical plants, which have many different chemical production facilities. For an emission reduction of acid gases, this study
employed a method to improve solubility of pollutants by decreasing the operating temperature of the scrubbers, increasing
the surface area for effective contact of gas and liquid, and modifying processes in the acid scrubbers. To reduce emission
of both amines and acid gases, pollutant gas components were first separated, then condensation and/or acid scrubbing, depending
on the chemical and physical properties of pollutant components, were used. To reduce emission of solvents, condensation and
activated carbon adsorption were employed. To reduce emission of a mixture gases containing acid gases and solvents, the mixed
gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower
in sequence. As a strategy to reduce emission of pollutants at the source, this study also employed the simple pollution prevention
concept of modification of the previously operating APC control device. Finally, air emissions of pollutants produced from
the chemical plants were much more reduced by applying proper APC methods, depending upon the types (physical or chemical
properties) and the specific emission situations of pollutants. 相似文献
914.
综放面风量调节范围与安全评价的数值模拟分析 总被引:3,自引:1,他引:2
结合实际算例 ,用迎风有限元方法 ,从理论上得出了采空区瓦斯绝对涌出量与工作面风量呈指数关系 ,采空区氧化带宽度与工作面风量呈负指数关系。按排放瓦斯要求和工作面生产的供风要求 ,确定风量下限 ,从防止采空区自然发火的角度 ,确定风量的上限 ,由此 ,得出合理的风量范围。引入了范围极差的概念 ,当风量极差越大 ,安全情况越好 ,反之 ,采空区的自然发火与瓦斯涌出二者是不可调和的 ,必须采取防治措施来提高风量极差值。 相似文献
915.
Removal of NAPLs from the unsaturated zone using steam: prevention of downward migration by injecting mixtures of steam and air 总被引:1,自引:0,他引:1
Steam injection for remediation of porous media contaminated by nonaqueous phase liquids has been shown to be a potentially efficient technology. There is, however, concern that the technique may lead to downward migration of separate phase contaminant. In this work, a modification of the steam injection technology is presented, where a mixture of steam and air was injected. In two-dimensional experiments with unsaturated porous medium contaminated with nonaqueous phase liquids, it was demonstrated how injection of pure steam lead to severe downward migration. Similar experiments, where steam and air were injected simultaneously, resulted in practically no downward migration and still rapid cleanup was achieved. The processes responsible for the prevention of downward migration when injecting steam-air mixtures were analyzed using a nonisothermal multiphase flow and transport model. Hereby, three mechanisms were identified and it was demonstrated how the effectiveness of these mechanisms depended on the air-to-steam mixing ratio. 相似文献
916.
Endosulfan in China 2—emissions and residues 总被引:4,自引:0,他引:4
Hongliang Jia Yeqing Sun Yi-Fan Li Chongguo Tian Degao Wang Meng Yang Yongshen Ding Jianmin Ma 《Environmental science and pollution research international》2009,16(3):302-311
Background, aim, and scope Endosulfan is one of the organochlorine pesticides (OCPs) and also a candidate to be included in a group of new persistent
organic pollutants (UNEP 2007). The first national endosulfan usage inventories in China with 1/4° longitude by 1/6° latitude resolution has been reported
in an accompanying paper. In the second part of the paper, we compiled the gridded historical emissions and soil residues
of endosulfan in China from the usage inventories. Based on the residue/emission data, gridded concentrations of endosulfan
in Chinese soil and air have been calculated. These inventories will provide valuable data for the further study of endosulfan.
Methods Emission and residue of endosulfan were calculated from endosulfan usage by using a simplified gridded pesticide emission
and residue model—SGPERM, which is an integrated modeling system combining mathematical model, database management system,
and geographic information system. By using the emission and residue inventories, annual air and soil concentrations of endosulfan
in each cell were determined.
Results and discussion Historical gridded emission and residue inventories of α- and β-endosulfan in agricultural soil in China with 1/4° longitude
by 1/6° latitude resolution have been created. Total emissions were around 10,800 t, with α-endosulfan at 7,400 t and β-endosulfan
at 3,400 t from 1994 to 2004. The highest residues were 140 t for α-endosulfan and 390 t for β-endosulfan, and the lowest
residues were 0.7 t for α-endosulfan and 170 t for β-endosulfan in 2004 in Chinese agricultural soil where endosulfan was
applied. Based on the emission and residue inventories, concentrations of α- and β-endosulfan in Chinese air and agricultural
surface soil were also calculated for each grid cell. We have estimated annual averaged air concentrations and the annual
minimum and maximum soil concentrations across China. The real concentrations will be different from season to season. Although
our model does not consider the transport of the insecticide in the atmosphere, which could be very important in some areas
during some special time, the estimated concentrations of endosulfan in Chinese air and soil derived from the endosulfan emission
and residue inventories are in general consistent with the published monitoring data.
Conclusions To our knowledge, this work is the first inventory of this kind for endosulfan published on a national scale. Concentrations
of the chemical in Chinese air and agricultural surface soil were calculated for each grid cell. Results show that the estimated
concentrations of endosulfan in Chinese air and soil agree reasonably well with the monitoring data in general.
Recommendations and perspectives The gridded endosulfan emission/residue inventories and also the air and soil concentration inventories created in this study
will be updated upon availability of new information, including usage and monitoring data. The establishment of these inventories
for the OCP is important for both scientific communities and policy makers. 相似文献
917.
With existing and proposed air-quality regulations, ecological disasters resulting from air emissions such as those observed at Copperhill, Tennessee, and Sudbury, Ontario, are unlikely. Current air-quality standards, however, may not protect ecosystems from subacute and chronic exposure to air emissions. The encouragement of the use of coal for energy production and the development of the fossil-fuel industries, including oil shales, tar sands, and coal liquification, point to an increase and spread of fossil-fuel emissions and the potential to influence a number of natural ecosystems. This paper reviews the reported responses of ecosystems to air-borne pollutants and discusses the use of animals as indicators of ecosystem responses to these pollutants. Animal species and populations can act as important indicators of biotic and abiotic responses of aquatic and terrestrial ecosystems. These responses can indicate long-term trends in ecosystem health and productivity, chemical cycling, genetics, and regulation. For short-term trends, fish and wildlife also serve as monitors of changes in community structure, signaling food-web contamination, as well as providing a measure of ecosystem vitality. Information is presented to show not only the importance of animals as indicators of ecosystem responses to air-quality degradation, but also their value as air-pollution indices, that is, as air-quality-related values (AQRV), required in current air-pollution regulation. 相似文献
918.
绵阳市环境空气质量监测系统中心控制软件开发应用研究 总被引:1,自引:1,他引:1
利用Microsoft office 2002软件开发绵阳市环境空气质量监测系统中心控制软件,具有智能模块化功能,从数据采集、整理、统计、计算、制图、制表等方面均可自动完成,直观、快捷、高效,可满足空气质量日报准确、及时上报要求,并可以较短时间内完成空气质量预报,可操作性强。 相似文献
919.
920.
中空纤维膜生物反应器处理炼厂浮选池出水试验研究 总被引:2,自引:0,他引:2
研究设计的膜生物反应器处理炼厂浮选池出水,在每天进水容积负荷1.0 kg COD/m3,进水COD浓度600 mg/L,MLSS为900~5500 mg/L的条件下,无论活性污泥表现正常还是膨胀,过滤出水中COD均稳定地小于90 mg/L,处理效果好于目前炼油厂的合建式曝气池(容积负荷为0.5 kg COD/m3左右,出水COD100 mg/L左右)。试验运行期间,膜通量最高可达到42 L/m2·h。该工艺的技术关键是采用特殊流态来降低膜堵塞的膜生物反应器和优良质量的膜。 相似文献