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101.
TiO2材料在紫外光照射下对废水中的有机物具有光催化降解作用,在环境保护污染治理方面有着广阔的应用前景,但其催化效率并不理想。本文介绍了材料TiO2光催化在废水处理中的研究现状,指出了限制TiO2光催化效率的影响因素,并综述了如何提高其光催化效率的几种途径。  相似文献   
102.
沈阳世园会玫瑰园采用环保型能源系统-土壤源热泵系统,该系统为清洁能源,节能高效,无废气、废水、废弃物排放,不会对环境造成污染,该系统符合国家能源发展趋势也符合国家能源利用政策。  相似文献   
103.
The effects of concentration of electrolytes on hydrogen production rate (HPR) at different applied voltages were experimentally evaluated in this research paper. The rate of hydrogen production was found to be directly proportional to the concentration of total dissolved solids and the efficiency did not change much with the change in the concentration of solids. Sensitivity analysis of the electrolysis system was also carried out to understand the relative importance of concentration of total dissolved solids (TDS) on the HPR, which can help for an optimum design.  相似文献   
104.
湖北省各主要地市水资源压力指数评价   总被引:2,自引:0,他引:2  
廖乐  吴宜进  毕旭 《环境保护科学》2012,38(3):82-86,94
以湖北省为研究区域,在前人研究基础上,从人口数量压力、水资源数量压力、水环境压力、水资源技术压力、水资源经济压力和水资源紧缺压力6个角度对2009年湖北省各主要地市的水资源压力指数进行了计算和分析。结果表明:湖北省内,武汉市水资源压力最大,鄂州次之,宜昌和黄石市等水资源压力相对较大,黄冈、荆州和十堰市等水资源压力相对较小;武汉市的人口数量压力和水资源紧缺压力大,鄂州市的水资源数量压力大,宜昌和十堰的水环境压力大,随州和黄冈市的水资源技术压力大,孝感市水资源经济压力较大。  相似文献   
105.
Ranked set sampling is a simple idea of great use. It was proposed half a century ago. The last 15 years or so have witnessed considerable development in the research and applications of ranked set sampling. In this paper, we give an overview on ranked set sampling. We review several variants of ranked set sampling developed since the original idea was proposed. We discuss the essence and the theoretical foundation of ranked set sampling. We present some novel applications of ranked set sampling in areas such as clinical trials, genetic quantitative trait loci mappings and others. By doing so, we wish to provide the reader with a philosophical view on ranked set sampling and shed some lights on a broader range of its applications.  相似文献   
106.
以悬浮物浓度、浊度、化学需氧量COD作为测试指标,通过小试对新型高效沉淀装置用于后期雨水的处理进行了研究。结果表明,混凝剂(PAC)和助凝剂(PAM)投加量分别为30 mg/L和1 mg/L时,对悬浮物SS、浊度和CODCr的平均去除效率分别达到了83.2%、76%和64.1%,出水水质达到了排放标准要求。  相似文献   
107.
Design and modernization of the micro turbojet engine technology have an important problem related to fuel consumption in terms of economics and environmental. For this purpose, in this study, first, energy and exergy efficiencies of the Jet A-1 and seven different alternative fuels were examined. Then, Exergy—based sustainability indicators were evaluated via exergetic irreversibility seperately. For this purpose, operational data of SR-30 micro-turbojet engine was taken as reference. According to this, the exergy efficiencies of engine as fuel for blending of methanol and ethanol were fixed with 22.35% and 20.56%, respectively. At the end of the study, some evaluations about alternative fuels and sustainability were made.  相似文献   
108.
介绍几种提高射流效率、充分利用其能量的方法,其中包括:等能量多次切割,流量(或流速)的脉动调制,有效利用淹没射流的空化段,研制开发优质喷嘴。  相似文献   
109.
Major polluters of man's environment are thermal power stations (TPS) and power plants, which discharge into the atmosphere the basic product of carbon fuel combustion, CO2, which results in a build-up of the greenhouse effect and global warm-up of our planet's climate. This paper is intended to show that the way to attain environmental safety of the TPS and to abide by the decisions of the Kyoto Protocol lies in raising the efficiency of the heat power stations and reducing their fuel consumption by using nonconventional thermal cycles. Certain equations have been derived to define the quantitative interrelationship between the growth of efficiency of the TPS, decrease in fuel consumption and reduction of discharge of dust, fuel combustion gases, and heat into the environment. New ideas and new technological approaches that result in raising the efficiency of the TPS are briefly covered: magneto-hydrodynamic resonance, the Kalina cycle, and utilizing the ambient heat by using, as the working medium, low-boiling substances.  相似文献   
110.
The World Commission on Dams (WCD) has now presented its final report on the problems with large dams. Many dam projects were found to be underperforming, especially those built for irrigation purposes. WCD also reports that many projects fail to meet current standards of social equity. A reallocation of costs and benefits is needed, but entrenched interests make this a difficult task. This article identifies shortcomings in large Asian irrigation projects: why the problems emerged, and what could be done to improve the performance of existing projects. The article argues that Asian irrigation agencies take mainly an engineering perspective, focusing on the dam itself. In a large number of cases, it takes over 10 years for the infrastructure to be installed and for the water to be delivered to the fields of the command area. Agencies need to improve their competence in dealing with social and environmental issues. This article argues that social and economic infrastructure is often inadequate; there is a need for an integrated view of the role of agriculture in development. Furthermore, adaptive management practices and water user participation can often be critical elements. To be successful, participation needs to be gender sensitive, and stakeholders at all income levels need to be consulted. To bridge the gulf between rhetoric and action, there is also a need for independent evaluation of dam projects.  相似文献   
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