山西省耕地资源的开发与保护

文章从山西能源基地建设为出发点,分析了山西省耕地资源利用的现状特点,提出了耕地资源合理利用的途径以及保护性措施。     

Economic sustainability and the preservation of environmental assets

The core requirement of sustainability is that current economic activities should not result in an excessive burden on future generations. This criterion is general enough to imply different decision rules for the preservation of environmental assets. Neoclassical economics does not have a sustainability criterion for environmental assets independent of the intertemporal efficiency criterion, which allocates environmental and man-made capital based on projected monetary benefits and costs. This criterion is examined in terms of the feasibility of valuing the benefits of environmental assets, the substitution possibilities between natural and man-made capital, and the ethical grounds for using efficiency as the sole determinant of the allocation of environmental assets. An alternative ecological sustainability criterion is the preservation of safe minimum levels of environmental assets in physical terms rather than the dollar value of a composite of natural and man-made capital. Safe minimum standards for environmental assets constrain the efficiency criterion in order to ensure the sustainability of economic systems. It is argued that the ecological approach to sustainability should limit the economic approach for decisions involving the allocation of environmental assets.     

ECONOMIC POLICIES FOR REGULATING AGRICULTURAL DRAINAGE WATER1

ABSTRACT: Agricultural drainage water is a major source of environmental pollution in many areas. This paper reviews the literature on the economics of nonpoint-source pollution and applies it to the regulation of agricultural drainage water. Four types of regulatory policies are considered. The empirical analysis is carried out for cotton production in the San Joaquin Valley of California. Variable inputs are the quantity of water applied and the type of irrigation system. All four policies can achieve economic efficiency under the conditions assumed here, but the policies differ in terms of the distributional impacts and administrative requirements.     

关于安全经济学的探讨

本文主要论述了如下基本概念问题: 1、安全的主要经济功能是保障社会经济的增值和有效地减少事故的经济损失。本文试图构造增值函数I(S)和损失函数L(S)来描述其功能。 2、安全经济学的基本任务是研究安全的经济效益和安全的经济利益规律,使其有效地调整和协调安全与经济的关系,指导安全经济决策。 3、本文试提出发展安全经济学应遵循的三个基本原理。 4、为综合揭示安全经济规律,本文还探讨了安全经济的功能函数F(S)、成本函数C(S)、负担函数B(S)和效益函数E(S)。 5、针对实际应用,本文还提出了一种安全投资的评价方法及其优化理论。     

电旋风除尘模型实验研究

本研究试图将电除尘器与旋风除尘器组合为一体,以求取得较高的除尘效率,并利用旋转气流实现自动清灰。本文介绍了切向进气直流式电旋风除尘的模型试验,通过实测不同工况下的除尘效率和压力损失,应用经典除尘理论,建立了相应的数学模型。     

SUSPENDED SEDIMENT AND METALS REMOVAL FROM URBAN RUNOFF BY A SMALL LAKE1

ABSTRACT: A small lake in the Chicago Metropolitan Area was from 91 to 95 percent efficient in removing suspended sediment and from 76 to 94 percent efficient in removing copper, iron, lead, and zinc from urban runoff. Sediments accumulated in the lake in the form of an organic-rich mud at an average rate of 20 millimeters per year; this reduced lake storage and covered potential habitat for aquatic organisms. Copper, lead, and zinc concentrations were closely associated with suspended-sediment concentrations and with silt- and clay-sized fractions of lake sediment. Although concentrations of mercury and cadmium were near detection limits in runoff, measurable concentrations of these metals accumulated in the lake sediments.     

WATER POLICIES FOR ENERGY DEVELOPMENT1

ABSTRACF: Examination of a series of studies of the economically efficient water allocations in the Upper Colorado River, Yellowstone River, and Great Basins indicate that water is not a serious general physical constraint on the development of energy resources, so long as public institutions do not hinder the exchange of water rights in markets. Energy development will cause limited impacts on other water-using sectors, principally agriculture. There appears to be little reason to develop large-scale water storage facilities, even during periods of reduced water production. Water storage developments appear to be necessary only when institutional constraints severely restrict water rights markets and transfers.     

几种碳氢燃料与空气混合物相对爆轰敏感度的测定

利用矩形激波管测定了几种碳氢燃料（丁烷，石脑油，ＪＣ５，戊烯，已烯）直接起爆时形成爆轰所需的临界起爆能，并以化学当量比的乙炔氧气混合物直接起爆形成爆轰的临界起爆能为基准，定义了一个无量纲常数Ｄｈ。再利用这个常数，比较了这几种燃料的相对爆轰敏感度。     

An approach for analysing the potential for material efficiency improvement

Material efficiency improvement saves energy and reduces the consumption of primary resources and reduces the volume of waste. In this article an approach for analysing the potential for material efficiency improvement is proposed and discussed. In this approach the product functions performed by the materials and various improvement measures are taken into account. The potential for material saving and associated energy saving is assessed and evaluated economically. In this paper the approach is tested in an analysis of the potential for material efficiency improvement with respect to plastic packaging in the Netherlands. The technical reduction potential is found to be 34 ± 7% (157 ± 30 ktonne virgin plastics). Realization of this potential would improve the energy efficiency of the lifecycle of plastic packaging by 31% (10 PJ in 1988). From our study we conclude that our approach can indeed be used to investigate the potential for material efficiency improvement. However, a reliable technical and particularly an economical assessment of reduction measures cannot be made until more detailed data become available.     

Metals recycling in the United States

Twenty-two metals for which secondary recovery is important, in terms of quantity and/or value, were compared and ranked for rate and efficiency of recycling, and availability of recycled metal. In general, their recycling rates trended upward over the period 1970–1993. Iron, aluminum, copper, gold, platinum, and lead accounted for most of the value of all secondary metal produced, while iron and steel dominated in terms of quantity produced and exported. The factors most influential on recycling rates are profitability, public support, organization of infrastructure, sortability, legislative support, and scrap purity. The share of supply accounted for by secondary metals is expected to surpass that of primary metals sometime in the next decade.