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771.
2 (1 and 24 h), SO2 (1 and 24 h), O3 (1 h) and PM10 (24 h). The AQI is linked to the new air quality guidelines in Finland. The AQI is based on acute health effects, but long-term effects on nature and materials are also taken into consideration. Subindices are calculated hourly for all pollutants and for a given hour the highest subindex becomes the AQI. AQI values are currently calculated for the center of Helsinki and for typical suburban areas.  相似文献   
772.
/ In 1990, the United States officially entered the era of pollution prevention with passage of the Pollution Prevention Act. This paper analyzes EPA's implementation of the Pollution Prevention Act from its passage in 1990 to the present. It examines the barriers EPA must overcome if it is to effectively integrate pollution prevention into its existing regulatory structure, including impediments created by statutory and organizational structure, the existing relationship between EPA and the groups it regulates, the fragmented implementation scheme of national environmental regulation, the balancing of conflicting demands advanced by powerful interests, industry's economic and technical concerns, and institutional inertia. It also examines issues such as industry commitment, the limits of prevention, and measurement concerns. The findings suggest that EPA's efforts at shifting to a pollution prevention regulatory ethic that holds primacy over pollution control are mixed. Its organizational structure, statutory authority, and incentives system still reflect a single-medium pollution control focus, appropriations for pollution prevention programs and activities are paltry compared to traditional pollution control programs, and participation in the program is voluntary. Yet, the findings also point to some promising programs that are working to institutionalize a pollution prevention regulatory ethic, and many states appear very committed to the concept.KEY WORDS: Pollution prevention; Source reduction; Pollution control; Alternative regulatory design; Barriers to implementation  相似文献   
773.
火灾现象的数值模拟及其应用   总被引:1,自引:0,他引:1  
本文讨论了模拟火灾现象的数值方法及其应用。着重研究了火焰发热、空气流动和烟尘传播的数学模型,讨论了紊流模型中浮力项的处理和边界条件的简化,并介绍了这一课题的研究现状和发展方向。  相似文献   
774.
有些特定的工作环境,在不能够确定空气状态参数的情况下,不允许对其进行通风处理。本文介绍了一种可以在线检测空气状态,并根据判定标志,自动开启换气设备的智能仪器。它对于工作环境的改善,人身健康的保护,仪器使用及物品存放的安全都具有较高的实用和推广价值。  相似文献   
775.
系统阐述了宏观控制化学毒物泄漏的主要技术问题,包括泄漏危险源的探讨;预警系统的设计;泄漏的预防以及应急救援等。  相似文献   
776.
This research considers the question of changing environmental values within the leadership of firms responsible for the management of pollution as an unwanted byproduct. Information was obtained from a pair of surveys mailed to the chief executive officers (CEOs) of the 50 largest firms listed within the mining and manufacturing directories of Colorado, Montana, Utah, and Wyoming in 1976 and again in 1986. The authors found that industry CEOs were more supportive of environmental concerns in 1986 than 1976, suggesting that ecological values have become institutionalized to some extent. Yet, there is little indication that this attitudinal shift in environmental concern among CEOs has been accompanied by a willingness to spend a larger proportion of the company budget on pollution control or to improve working relationships with federal regulatory officials.  相似文献   
777.
The British pride themselves on their long tradition of landscape management rooted in the aristocratic and landowning classes of the 18th and 19th centuries. The British also emphasize that the rise of modern pollution control began in the Victorian industrial era with the emergence of the national Inspectorates and the local Commissioners of Sewers. All these traditions are rooted in British social history, which was heavily influenced by class, power, and the changing shape of industrial and agricultural development. In modern Britain, affected by industrial recession, where concern over jobs and growth appears to dominate public and political attention, as well as public spending cuts that sap the morale and effectiveness of the major regulatory agencies, attitudes toward, and the execution of, environmental protection are undergoing a subtle but profound revolution. It is slowly but agonizingly being recognized that economic growth and social well-being cannot be disconnected from environmental processes and the limits these impose on management and technological intervention. A 21st century Britain will have to integrate conservation with development in order to survive.  相似文献   
778.
Air pollution has become a serious problem in China as a result of that country's efforts in the last 30 years to become a great industrial power. The burning of coal, which currently provides over 70% of all China's energy needs, is a major source of air pollution. Because Chinese coal is high in sulfur and ash content and because most combustion devices in China have low efficiencies, SO2 and particulate emissions are a serious problem and are comparable to or exceed those found in many countries that are much more industrialized. Although most coal is burned in North China, acid precipitation is most severe in South China because of the lack of buffering loess dust found in the former region.The Chinese government has already taken major steps to mitigate air pollution, such as relocating polluting industries, supplying coal with lower sulfur content, using gas instead of coal for residential heating, and levying fines on industries that exceed pollution standards. Atmospheric environmental impact assessment (AEIA) is also required for all major new projects. This article describes three types of mathematical diffusion models and field and wind-tunnel experiments that are used in such assessments.The Chinese authorities believe that a range of technological, managerial, locational, and behavioral changes must be effected before the air of Chinese cities can be significantly improved.  相似文献   
779.
Traditional air pollution management practices are examined using the human ecological framework adopted by Boyden and others (1981) in their study of Hong Kong—the biohistorical or biosocial approach. The subsequent analysis of current air quality management practices assesses their effectiveness in protecting the overall health of both humans and the natural environment. The uncertainties inherent in air pollution management practices which emerge highlight the need to reduce emissions rather than rely on scientific knowledge to define clean air. The assessment also clearly defines roles for research in various areas such as atmospheric models, health effects, and environmental damage. The final recommendations emphasize the need for the introduction of such incentives to reduce emissions as economic instruments and warn against using health information to define clean air. Health and environmental damage information can, however, be used in risk assessment strategies together with atmospheric dispersion models.  相似文献   
780.
锅炉烟尘、烟气监测质量控制探讨   总被引:1,自引:0,他引:1  
针对锅炉烟尘、烟气监测质量控制问题,结合实际情况进行分析。  相似文献   
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