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991.
John J. Knightly Reece Morehead 《Journal of the American Water Resources Association》1979,15(5):1221-1225
ABSTRACT: The Water Resources Scientific Information Center (WRSIC) provides comprehensive indexing/abstracting for the water resources literature. To determine in one objective way the coverage of this information service from a user's point of view, an extensive sampling of the journal literature was used to determine extent to which 10 leading water resources journals are indexed and abstracted by the system. Coverage is so high that some users will want to change toward greater use of the system. 相似文献
992.
993.
中国西部贫困地区可持续发展研究 总被引:22,自引:2,他引:20
赵曦 《中国人口.资源与环境》2001,11(1):82-86
本文探讨了贫困与可持续发展的相互关系。在系统阐释中国西部贫困地区可持续发展面临的现实问题、困难和障碍的基础上,着重围绕西部贫困地区可持续发展的基本内容和实施途径进行了综合性的分析和研究。 相似文献
994.
Donald A. Downing 《Journal of the American Water Resources Association》1975,11(2):345-355
ABSTRACT. The article proposes the use of certain water and sewer extension pricing and investment policies. Such policies would complement an urban growth policy designed to guide the location and timing of growth in urbanizing areas. Proposed pricing policies are based upon marginal cost principles. The types of pricing policies discussed include benefit assessments, connection fees, and user charges. Proposed investment policies deal with the division of financing responsiblities between the public and private sectors. Discussion of each proposal explains the economic influence of the proposed policies upon key decision makers in the land development process. The application of proposed pricing and investment policies in the case study communities is mixed. In Knoxville, Tennessee, where pricing and investment policies reflect the proposed policies, no urban growth policy exists. In Lexington, Kentucky, mixed pricing and investment policies do not complement what is a relatively good urban growth policy. In Greensboro, North Carolina, reasonably effective pricing and investment policies complement other policies which provide some guidance to the urban growth pattern. It is hoped that the article will increase the recognition of utility pricing and investment policies as one means of implementing urban growth policy. 相似文献
995.
着重叙述了测震单台数字化分析软件SSDP、NNVSIAS的系统设置及使用技巧 ,并就工作中出现的一些问题给出具体的解决办法 ,特别对NNVSIAS在震相分析中的正确使用、震源对话框的恰当运用给出了详细的说明。 相似文献
996.
提出在加强对餐饮业环境管理的同时,务必注意油烟监测中的技术问题。指出油烟测试中,不锈钢滤筒优于刚玉滤筒;应用红外分光法测定油烟含量,不受油品成分限制,结果较准确、可比。由于厨房的实际工作灶头数不同,每个灶头发热功率的不同和每个灶头产生油烟量的不同,必须把实际工作灶头数换算为折算工作灶头数,才具有一致性和可比性。折算工作灶头数n=(工作灶头数/实际灶头数)×(排风罩面积/1.1)。 相似文献
997.
本文阐述了省级环境监测中心站在整个国家环境监测网络中的重要地位和作用。回顾了我省环境监测中心站这些年来的工作,当前存在的困难和问题,以及如何对我省环境监测中心站进行体制改革的思考。 相似文献
998.
999.
Richards N Hall S Scott K Harrison N 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1446-1450
Exposure to the nonsteroidal anti-inflammatory drug (NSAID) diclofenac resulted in the near extinction of three species of Gyps vultures on the Indian subcontinent. Other NSAIDs present in the environment, including flunixin, may pose a similar risk. In the course of a study to determine the feasibility of detecting NSAIDs in keratinous matrices (i.e., hair, nails and feathers) using GC-MS, wool opportunistically collected from a sheep treated with flunixin was analysed for residues. Flunixin was detected qualitatively in external wool wash and extract samples. While residues of veterinary agents and pesticides have previously been found in sheep’s wool, our preliminary investigation provides the first instance of an NSAID being detected in this matrix. Here we provide the sample preparation methods and GC-MS parameters used to enable further refinement as part of ongoing conservation and consumer quality control measures. 相似文献
1000.
The analysis of data of the ground-level ozone concentration and accumulated ozone exposure over a threshold of 40 ppb (AOT40)
in the rural areas of Lithuania is presented. Trends in the annual ozone mean, 95{th} and 25{th} percentiles were determined
as statistically not significant at Preila and Rugsteliskes sites during the 1994hbox{–}2004 period. Trends in the ozone concentration
and its percentiles in the air masses arriving to Preila station in “polluted” and “unpolluted” sectors have been examined.
Statistically significant changes in the ozone annual mean and 25th percentile were found in air masses in both “polluted”
and “unpolluted” sectors in the 1988hbox{–}2002 period. The trend analysis in the ozone monthly mean and percentiles for each
month of the year revealed the main changes in the ozone level in both sectors during January-May. Insignificant downward
trends in monthly 95th percentile in “unpolluted” sector and upward trends in “polluted” sector were found during summer months.
Values of AOT40 for the protection of forests as well as crops and semi-natural vegetation were determined during the 1994–2004
period. The estimated AOT40 values for the protection of forests were lower than the critical level at Lithuanian rural sites
but AOT40 values for the protection of crops and semi-natural vegetation were found to be higher than the critical level at
both sites. 相似文献