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排序方式: 共有963条查询结果,搜索用时 15 毫秒
601.
近年来,环境类服务购买在政府购买公共服务中的比重不断增多,作为政府购买公共服务的下属概念,其监督不仅存在政府购买公共服务监督的一般性问题,还存在环境领域的专门问题,概括后主要表现为监督主体缺位、被监督对象比例设置不科学、监督内容过于宽泛、监督制度构建有限等。推动全国性专门立法、定位不同监督主体的功能、明确以"合同"为核心的监督内容、拓展配套制度是完善我国政府购买环境公共服务监督机制的必由之路。 相似文献
602.
Jing-Li Fan Qian Wang Shiwei Yu Yun-Bing Hou Yi-Ming Wei 《Mitigation and Adaptation Strategies for Global Change》2017,22(8):1229-1248
Employing global multi-regional input–output models, this paper revisits the carbon dioxide (CO2) emission trade (including exports and imports) and assesses their positions in the national emissions of 14 major countries with large national emissions or large emission trades during 1995–2009. It especially explores the evolution of the emission trades of these countries from both continuous time series and comparative perspectives, in order to provide an explanation for CO2 emission spillovers across countries. The main findings obtained were as follows: (1) China was the largest CO2 exporter to other countries, accounting for over 20 % of global exports since 2005; the CO2 exports of the United States of America (USA), Germany, and Japan varied slightly over this time period, but overall, their proportions had decreased. (2) The CO2 imports of the USA were the largest, occupying around 20 % of the global CO2 imports; meanwhile, China’s CO2 imports increased rapidly and ranked the second largest. (3) For Chinese Taiwan, its proportion of CO2 exports in production-based emissions ranked the highest while that of the USA ranked the lowest; highly CO2 import-dependent countries with an over 40 % proportion of CO2 imports in its consumption-based emissions included France, Germany, Italy, and Spain, while China, India, and Russia remained the lowest, distinguished from their physical energy imports. These results suggested that the global policy makers should take the CO2 emissions in trade into consideration when carefully accounting for national emissions inventories. 相似文献
603.
西北地区农村生活污水处理工作是中国环境保护工作的重要组成部分.针对西北地区农村生活污水处理目前没有专门设计的处理工艺,结合西北地区农村污水处理的实际特点,在对比分析了几种常用农村生活污水处理工艺特点及适用范围基础上,选择了四套家用型污水处理技术,为建立西北农村生活污水处理新模式提供借鉴与科技支撑,为西北地区农业面源污染的控制提供技术支持. 相似文献
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606.
Wang Haiying Fan Zhenjun Hou Xiaoli Dong SuochengInstitute of Geographical Sciences Natural Resources Research CAS Beijing China 《中国人口.资源与环境(英文版)》2004,2(1)
Since the 1990s, the Yellow River stream has been temporarily interrupted for several years, which affects the development of society, the economy and human life, limits the economic potential of the drainage areas, and especially causes great harm to regions on the lower reaches. Based on the analysis of the relationship between the development of society and economy and water scarcity, the author thinks it is necessary to optimize and adjust the industrial structure that has extravagantly consumed enormous amounts of water, and to develop ecological agriculture, industry and tourism which are balanced with the ecological environment. Finally, the author puts forward several pieces of advice and countermeasures about how to build the economic systems by which water can be used economically. 相似文献
607.
本文根据酵母废液的水质特点,采用了常温升流式厌氧污泥床处理工艺,即温度在26.8-28.0℃,进水COD为7129-9823mg·l^-1时,达到CDO去除率66.0-71.0%,同时,沼气产率为2.4-3.0L·l^-1·d^-1,沼气中烷含量为61.5-69.1%。该法耗能小,沼气可回收,经济效果明显。 相似文献
608.
2009年,国家安监总局提出了深入开展“三项行动”,切实加强“三项建设”活动,核心是查处治理隐患。由此可见,隐患排查治理是近年来安全监管的主要内容和中心任务,而企业作为隐患排查治理责任主体,如何建立隐患排查治理长效机制则是安全管理工作的重中之重。 相似文献
609.
Parabensare are widely used as preservatives in cosmetics, foods and pharmaceutical products. Although parabens have generally been considered safe, several studies have cautioned that parabens have estrogenic or endocrine-disrupting properties. With the present study, the effects of four concentrations of propylparabens (200, 500, 1000, and 2000 mg L?1) on fecundity, development and the lifespan of Drosophila melanogaster have been investigated. Decreased daily mean egg production was found in all exposure groups. In addition, the 100 mg L?1 treatment significantly shortened egg-to-prepupa time and extended flies lifespan, consistent with a significant reduction in malonyldialdehyde (MDA) level and an increase in superoxide dismutase (SOD) activities. The 200 mg L?1 treatment prolonged egg-to-prepupa time and decreased flies lifespan significantly, being consistent with a significant increase in MDA level and reduction in SOD activities. 相似文献
610.