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871.
使用寿命长的微孔薄膜复合滤料过滤石灰窑气,把温度控制在78~200℃之间。过滤风速小于2.50m/min以内,就可以确保净化后的窑气含尘浓度达标。  相似文献   
872.
采空区火源位置探测技术现状及发展方向   总被引:3,自引:0,他引:3  
概述了国内外采空区火源位置探测技术的现状,着重介绍了温度探测法、气体探测法、磁力探测法、数理解算法、电磁波探测法及电阻探测法等探测技术,并展望了国内外采空区火源位置探测技术的发展方向  相似文献   
873.
介绍了中心平台油气处理工艺、清除采出砂的必要性和要求。论述了地面集输系统的除砂方法以及中心平台除砂工艺,评价了除砂方法和工艺的优、缺点。供海上油田作业时借鉴。  相似文献   
874.
Am-Be中子源和C5r源是一种极为有效的测井技术,但给测井操作员带来头昏、乏力、白细胞降低等症状,担心影响健康和生育。本文根据在江汉油田对100多名测井放射人员进行的379次有效资料统计,对个人剂量监测和临床观察.阐明测井放射性工作人员受中子、γ线全身照射的个人剂量水平及其医学影响程度。  相似文献   
875.
The author contributed to a short ‘in service’ course for staff engaged on a World Bank upgrading project for Ethiopian housing. The project includes both the building of new houses by self‐build co‐operatives on the periphery of Addis Ababa, and the upgrading of a dense inner city area in conditions of acute deprivation. The paper is a highly personal account of the author's impressions of the value of such initiatives.  相似文献   
876.
Recent Central Government advice to local authorities on the matter of business and industry applications Has been towards a relaxation of controls and a facilitating of development. Also the general worsening of the economy in the last few years has probably increased the interest with which local councillors regard industrial applications for planning permission. A study of refusal rates for industrial applications for 317 Districts taken from the DOE Development Control Returns and a case study in Coventry District of all industrial applications in 1970 and 1980 suggest that despite these pressures planning authorities are not lowering standards.  相似文献   
877.
This paper introduces the five papers that follow, all of which were originally presented at a workshop titled Monitoring the Environment: Scales, Methods, and Systems in Historical Perspective. The workshop, sponsored by the Society for the History of Technology and the American Society for Environmental History, examined past efforts to develop tools, methods, and systems for measuring or monitoring some aspect of the physical environment. Four of the papers included here focus on various aspects of air quality monitoring; the fifth has to do with monitoring the earth from space. Despite differences in time period and approach, each article examines how specific tools and methods – and the motivations for developing those tools and methods – evolved. Among other things, these papers make clear that systems for monitoring various aspects of the physical environment are shaped by a variety of stakeholders and suggest that efforts to construct such systems should not be viewed as a purely technical task.  相似文献   
878.
Many governments use technology incentives as an important component of their greenhouse gas abatement strategies. These carrots are intended to encourage the initial diffusion of new, greenhouse-gas-emissions-reducing technologies, in contrast to carbon taxes and emissions trading which provide a stick designed to reduce emissions by increasing the price of high-emitting technologies for all users. Technology incentives appear attractive, but their record in practice is mixed and economic theory suggests that in the absence of market failures, they are inefficient compared to taxes and trading. This study uses an agent-based model of technology diffusion and exploratory modeling, a new technique for decision-making under conditions of extreme uncertainty, to examine the conditions under which technology incentives should be a key building block of robust climate change policies. We find that a combined strategy of carbon taxes and technology incentives, as opposed to carbon taxes alone, is the best approach to greenhouse gas emissions reductions if the social benefits of early adoption sufficiently exceed the private benefits. Such social benefits can occur when economic actors have a wide variety of cost/performance preferences for new technologies and either new technologies have increasing returns to scale or potential adopters can reduce their uncertainty about the performance of new technologies by querying the experience of other adopters. We find that if decision-makers hold even modest expectations that such social benefits are significant or that the impacts of climate change will turn out to be serious then technology incentive programs may be a promising hedge against the threat of climate change.  相似文献   
879.
构造人工湿地技术及其应用   总被引:6,自引:0,他引:6  
通过介绍构造人工湿地对特征污染物即悬浮物、有机物、氮、磷、细茵以及重金属的去除研究,阐述了污染物去除的基本特征和作用机理,并在植物的选择、设计参数、动力学研究三方面就构造湿地设计进行了探讨与分析,对未来的研究工作作了展望。  相似文献   
880.
PrescreeningteratogenicpotentialofchlorinateddrinkingwaterdisinfectionbyproductsbyusingHydraregenerationasayJiYuantangDepar...  相似文献   
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