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241.
围绕废旧物资增值税税征管理政策调整完善工作,论述了其在废旧物资“产废”、“收废”、“利废”三大基础环节的现状及存在的问题,提出合理平衡三大环节的经济利益及打造三大环节税征链扣的建议,为切实做好废旧物资税征政策调整完善工作提供参考。 相似文献
242.
根据国家八五科技攻关专题“易燃易爆重大危险源监控及预警技术研究”技术总结报告提供的素材,通过对危险品储罐的安全状态实时监测、建立泄漏扩散预测模型及其计算机仿真装置,构成监控危险源的预警系统,为预防重大事故、保障安全生产提供技术支撑 相似文献
243.
Richard Field Hugh Masters Melvin Singer 《Journal of the American Water Resources Association》1982,18(2):265-270
ABSTRACT: This paper discusses the economics, advantages, potential applications, and status and future research needs of porous pavements. Porous pavements are an available storm water management technique which can be used on parking lots and low volume roadways in order to reduce both storm water runoff volume and pollution. In addition, ground water recharge is enhanced. Also, cost reductions result due to elimination of curbs, drains, and small sized storm sewers. Porous asphalt pavements consist of a relatively thin course of open graded asphalt mix over a deep base of large size crushed stones. Water can be stored in the crushed stone base until it can percolate into the subbase or drain laterally. Other porous pavement types include concrete lattice blocks and a porous concrete mix. 相似文献
244.
Michael I. Muiga George W. Reid 《Journal of the American Water Resources Association》1979,15(3):838-852
ABSTRACT: Mathematical modeling techniques are used to develop predictive equations for cost of water and waste water treatment processes in developing countries utilizing socioeconomic, environmental, and technological indicators. Predictive equations are developed for each of the three regions (Africa, Asia, and Latin America) for construction, operation, and maintenance costs of slow sand filter, rapid sand filter, stabilization lagoon, aerated lagoon, activated sludge, and trickling filter. Data analysis indicated that cost of water treatment processes is a function of technological indicator (percentage of imported materials), population, and the design capacity. The variables which gave the best correlation for waste water treatment cost were population, design flow, and the percentage of imported waste water disposal materials. 相似文献
245.
Risk analysis for road and rail transport of hazardous materials: a simplified approach 总被引:2,自引:0,他引:2
Roberto Bubbico Sergio Di Cave Barbara Mazzarotta 《Journal of Loss Prevention in the Process Industries》2004,17(6):477-482
A simplified approach to transportation risk analysis for road and rail transport of dangerous goods is proposed, which is based on the use of a product databank, containing the impact areas for a number of pre-selected accidental scenarios, and on the selection of a few typical average values of the involved parameters, relevant to the type of transport activity and to the route. Such an approach enables also a non-specialist to very rapidly perform a transportation risk analysis, obtaining both individual and societal risk measures for the study case(s): the results may be used to support a decision making process, and/or as a basis for a more in deep analysis. 相似文献
246.
纳米储氢材料贮存使用安全评估方法研究 总被引:2,自引:1,他引:1
李传贵 《中国安全科学学报》2003,13(9):24-26
储氢材料贮存使用的安全可靠性是安全工程和可靠性领域中的特殊问题 ,纳米储氢材料的使用 ,其安全性和贮存可靠性同时占有重要地位。笔者依据纳米储氢材料使用和在正常贮存状态下的失效特点 ,应用Poisson过程理论建立纳米储氢材料使用和贮存安全性评估数学模型和统计分析方法 ,给出了在一定置信度下纳米储氢材料贮存寿命与可靠度之间的关系表达式。为纳米储氢材料和新型能源材料研究和使用等提供了理论基础和应用控制的方法。 相似文献
247.
The stability in the energetic materials' thermal decomposition reaction is developed from both transient mass and heat transfer equations simultaneously. The derived equation is the sufficient and necessary condition for the reaction system's stability, which was expressed as:
In this stability equation, a modified Semenov number φ is the expressed function of three kinetic parameters, i.e., n, and β and two variables, i.e., x and θ, respectively. A reaction system is stable if its evaluated modified Semenov number satisfies this stability criterion. In the case of the minimum modified Semenov number φm, we can deduce the stability equation at critical condition as
The criteria of stability for the explosives TNT, RDX, PETN and HMX were evaluated using this formula, which was expressed θc as function of x at given n, η and various β as parameters. 相似文献
248.
249.
John Cairns 《Journal of the American Water Resources Association》1986,22(5):841-842
ABSTRACT: Direct measurement of response thresholds of complex biological systems to toxic chemicals is now possible using microcosms and other simulation techniques. Extrapolation to no-observable response using application factors and data from single species toxicity tests is less precise than direct measurements. 相似文献
250.
Malgorzata Kwiecień 《Environmental monitoring and assessment》1997,46(3):191-207
A new, direct method was developed for quantifying inorganic particulate aerosols trapped by the forest canopy, and for determining the resulting input of elements to a forest ecosystem. The method is based on direct measurements of only six parameters. Using this method, it is possible to determine the load of aerosols trapped by the forest canopy and deposited to leaves, as well as the load of aerosols falling to the forest floor by impaction on plants. It is also possible to estimate the aerosol input of soluble and insoluble elements to an ecosystem. With this new method it has been found that the load of aerosols trapped by the canopy of a mixed forest located in the Rybnik Coal Basin averaged 189.0 kg x ha-1 x growing season-1, or 39.3% of the total inorganic particles reaching the ecosystem. The trapped aerosols provided 13.4 kg x ha-1 of soluble nitrogen and 0.91 kg x ha-1 of insoluble nitrogen over the growing season. At the same time, the input of soluble nitrogen from the atmosphere with rainfall to an open area averaged 13.9 kg x ha-1, and the input of insoluble nitrogen with inorganic dusts averaged 1.4 kg x ha-1. 相似文献