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211.
说明目前乡镇工业企业中职业安全卫生问题十分突出。据调查,厂矿工伤事故发生率为8.23%,每千名职工的工伤发生率为2.66人,每十万名职工的工伤死亡率为7.02人。通过对事故的原因进行分析,提出了加强监督管理的建议。  相似文献   
212.
张国斌 《灾害学》1995,10(1):36-38
本文概述了在制定和部署抗震救灾工作预案时,所引起地震误传事件的经过、对社会造成的影响,以及采取的对策和所汲取的教训。  相似文献   
213.
The breakpoint rainfall hydrology and pesticide options of the field scale model CREAMS (Chemicals, Runoff, and Erosion from Agricultural Management Systems) were used to predict average concentrations of hexazinone [3 cyclohexyl-6-(dimethyl-amino)-1-methyl-1,3,5-triazine-2,4(1H,3H)-dione] in stormflow from four forested watersheds in the upper Piedmont region of Georgia. Predicted concentrations were compared with measured concentrations recorded over a 13-month period. CREAMS accurately predicted hexazinone concetrations in the initial stormflow events which also contained the highest concentrations. The model underestimated the hexazinone concentrations in stormflow two months and greater following pesticide application. In a companion study, the daily rainfall option of the CREAMS model was used to evaluate the reltive risk associated with the maximum expected concentration of hexazinone, bromacil (5-bromo-3 sec-butyl-6 methyuracil), picloram (4-amino-3,5,6 trichloropicolinic acid), dicamba (3,6-dichloro-0-anisic acid), and triclopyr {[(3,5,6-trichloro-2-pyridinyl)oxy] acetic acid} in stormflow from small forested watersheds. The model predicted the following order of potential residue appearance in stormflow: bromacil>triclopyr>hexazinone>picloram>dicamba. Subsurface movement of residues via interflow and deep leaching losses are not simulated by the version of CREAMS used in these studies.  相似文献   
214.
The physical processes governing flow and pollutantdispersion at the neighbourhood scale, a spatial scaleintermediate between the street scale and the city scale, is notwell understood. Furthermore, it is not clear whether a traditional approach using averaged characteristics such as theaerodynamic roughness length is sufficient to predict the concentration field at this scale. To investigate pollutant dispersion in a real urban area, three field experiments were designed within the UK-URGENT programme sponsored by NERC. Theexperiments were performed in the City of Birmingham using a finite duration release of inert, non-toxic and non-depositingtracers, vis. perfluoromethylcyclohexane (PMCH) and perfluoromethylcyclopentane (PMCP). Measurements were taken using air bag samplers placedin an arc at 3.5 km (first experiment) and 1 km (second andthird experiments) from the source; some trap samplers wereplaced outside the main arc in the outskirts of the city. Measurements were analysed in the laboratory using anovel gas-chromatography technique. Data so obtained werecompared with predictions from a simple steady-state modeland a time-dependent model. The concentration-time serieswere very asymmetrical with a sharp rise, a plateau followedby a relatively slow decrease and finally a long-livedplateau above (or possibly very slow decrease to) thebackground level.  相似文献   
215.
It is a common experience that public administrations tend to shy away from the explicit acknowledgment of quantitative risk levels. Faced with extreme concentrations of population and of industrial activities, including LPG and liquid chlorine storage, within a very small land area, Hong Kong has faced up to the issue of major man-made hazards by “thinking the unthinkable” and adopting explicit risk guidelines. This article describes how these guidelines were developed and the arguments that led to their adoption. It is emphasized that the risk guidelines are not rigid standards but simply a method of focusing decision making and ensuring that any decision to contravene the guidelines is taken at an appropriately senior level in the administration. The way in which the guidelines have been incorporated intimately into the planning and decision-making process is described and details are given on how this has led to the implementation of a variety of measures that have greatly reduced both societal and individual risk from certain types of chemical storage and chemical processing installations in Hong Kong. The opinions in this paper represent the views of the authors and not necessarily those of the Hong Kong Government.  相似文献   
216.
本文在分析农业人口转移数量、经济效益、社会商品销售额、集镇容纳能力的基础上,研究了集镇合理人口规模的界线。  相似文献   
217.
我国乡镇工业企业的发展与环境、资源的协调问题已经成为我国发展与环境、资源关系方面的大问题。实行工农相对分离,组建乡村工业区,是提高乡镇工业企业素质、效益,强化乡镇工业企业优化组合、规模经营的有效途径;是保护环境,实现资源有效利用的基础工作之一;是提高农业劳动生产率,实现农业规模经营的基础工作之一。  相似文献   
218.
Transgenic plants are now being used to develop pharmaceutical and industrial products in addition to their use in crop improvement. Using confinement requirements, these transgenic plants are grown and processed under conditions that prevent intermixing with commodity crops. Regulatory agencies in the United States have provided guidance of zero tolerance of these new industrial crops with commodity crops. While this is a worthy goal, it is theoretically unattainable. In spite of the best containment practices, there is a potential risk using any system of production due to unforeseen incidences including natural disasters or exposure to workers. The precautionary principle has been used for numerous regulated articles in addressing the potential risks of new products and technology based on a risk assessment in similar situations. We present here a risk assessment model that could be used as a start to develop an accepted model for the industry. The model is based on current risk models used for other regulated articles, but adapted for these types of products. This could be used to determine action levels in the event of an unintended exposure or to ensure that detection or confinement methods are adequate to avoid risks. As an example, aprotinin, a therapeutic protein now being produced in maize, was evaluated for potential risk to humans using this model.  相似文献   
219.
Oil refining is among the industrial activities that emit considerable amounts of air pollutants into the atmosphere. Nitrogen oxides are important air pollutants that are emitted by oil refineries as products of combustion processes. The ambient air concentrations of nitrogen oxide (NO) and nitrogen dioxide (NO2) were monitored continuously at a site close to an oil refinery, near the city of Corinth in Greece, during autumn 1997 together with the main meteorological parameters. The contribution of the oil refinery to the measured atmospheric levels of nitrogen oxides was estimated. The ambient air concentration of nitrogen oxides in the area surrounding the oil refinery were generally lower than the ambient air concentrations in the urban area of Athens in Greece, and the NO2 levels were always below the existing air quality standards. The influence of the refinery emitted NOx in the photochemical production of ozone seems to be more important in terms of human and vegetation exposure given the high ozone backgrounds measured in the area.  相似文献   
220.
The literature guides environmental planning and, specifically, how to use ecological rehabilitation projects to achieve long-term planning goals and landscape-scale environmental sustainability. There is, however, a perceived gap between principles in the literature and the use of them by practitioners involved in smaller-scale ecological rehabilitation projects. Using interviews with practitioners involved in 11 projects within the Regional Municipality of Waterloo, Ontario, Canada, we tested whether practitioners used five principles for effective planning and implementation of ecological rehabilitation that we derived from the literature. These five principles were: establishing political and ecological context, using ecologically appropriate objectives and practices, using comparative multidisciplinary and cross-scale approaches, using adaptive planning and implementation, and establishing good communication within and external to projects. Few projects followed all five principles, and practitioners indicated that they used three more project-specific principles: obtaining political/social support, promoting projects and changing attitudes about projects, and securing sufficient and persistent funding to maintain a project's life. While the literature emphasizes that ecological rehabilitation is only effective if projects are coordinated on a watershed basis, most practitioners focused solely on the goals of their specific project. The gap between literature and practice may arise because most practitioners are new to the field of ecological rehabilitation and still are focused on the methods involved. Time pressures force practitioners to obviate the literature and get projects started quickly, lest support evaporate. Complicating these difficulties is decreased support from federal and provincial governments for large-scale environmental planning. It is unclear whether ecological rehabilitation projects in Waterloo Region (at least) will ever become effective at promoting landscape-scale ecological goals or remain smaller-scale stop-gaps.  相似文献   
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