首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   99027篇
  免费   1230篇
  国内免费   1135篇
安全科学   3902篇
废物处理   3647篇
环保管理   15047篇
综合类   21513篇
基础理论   27643篇
环境理论   75篇
污染及防治   18849篇
评价与监测   5901篇
社会与环境   4166篇
灾害及防治   649篇
  2022年   828篇
  2021年   815篇
  2020年   665篇
  2019年   879篇
  2018年   1249篇
  2017年   1306篇
  2016年   2267篇
  2015年   1868篇
  2014年   2601篇
  2013年   9288篇
  2012年   2552篇
  2011年   3134篇
  2010年   3425篇
  2009年   3574篇
  2008年   2757篇
  2007年   2666篇
  2006年   2858篇
  2005年   2714篇
  2004年   2996篇
  2003年   2866篇
  2002年   2443篇
  2001年   2909篇
  2000年   2327篇
  1999年   1645篇
  1998年   1417篇
  1997年   1420篇
  1996年   1549篇
  1995年   1637篇
  1994年   1532篇
  1993年   1379篇
  1992年   1376篇
  1991年   1349篇
  1990年   1296篇
  1989年   1277篇
  1988年   1113篇
  1987年   1030篇
  1986年   1010篇
  1985年   1095篇
  1984年   1190篇
  1983年   1194篇
  1982年   1189篇
  1981年   1121篇
  1980年   958篇
  1979年   961篇
  1978年   844篇
  1977年   739篇
  1976年   675篇
  1974年   654篇
  1973年   688篇
  1972年   698篇
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
71.
In a 1981 survey of 436 Florida citrus growers, 27 pesticide related poisoning incidents were reported that were to have taken place within one year of the interview date. From these reports it is possible to estimate that there are 376 citrus fieldworker related poisonings per year in Florida. This number of estimated poisonings may be developed into an incidence rate of 113 fieldworker poisonings per 10,000 fieldworkers.  相似文献   
72.
   Global change, i.e. the mega-process radically transforming the relationship between nature and human civilization since the end of World War II, is investigated from the point of view of systems analysis. It is argued that this unbridled process should rather be domesticated by planetary control strategies transpiring from a new science called “geocybernetics”. The formal aspects of geocybernetic theory are sketched and illustrated in a tutorial theatre world reflecting the overall environment and development problematic. Within this setting a straightforward operationalization of the sweeping “sustainable development” ideal through a set of concise paradigms can be achieved. Evidence is provided that geocybernetics is actually feasible on the basis of earth system modelling and fuzzy-control techniques.  相似文献   
73.
74.
This paper examines the relationship between survivor reactions to a downsizing and retention subsequent to a downsizing. We hypothesize that survivors who experience the downsizing as distributively, procedurally, and interactionally just and who see top management as trustworthy will feel more attached to the organization because each reduces the threat inherent in downsizing. In addition, we hypothesize that survivors who feel empowered will also feel more attached to the organization because they feel better able to cope with the downsizing. We further hypothesize that those survivors who feel more attached to the organization following the downsizing will be more likely to remain with the organization in the coming year. The theoretical model is tested on a sample of aerospace employees who survived an organizational downsizing. The trustworthiness of management, distributive justice, procedural justice, and three dimensions of empowerment are found to facilitate more organizational attachment. Higher levels of attachment are found, in turn, to facilitate less voluntary turnover in the year following the downsizing. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
75.
76.
77.
78.
79.
80.
Material suppliers and industrial metabolism   总被引:1,自引:1,他引:0  
Life Cycle Assessment (LCA) is not sufficiently tailored to the analysis of strategic environmental problems of material suppliers. Sustainable development calls for a reduction by a factor of 10 to 20 in the material intensity of the economy, a situation which leads to dramatic shifts in markets for raw materials. Furthermore, a material supplier might have major improvement options in the material’s numerous downstream uses. LCAs, however, can’t cover these two aspects. An adapted form of Substance Flow Analysis (SFA) may be an answer. This approach defines a system in relation to the flow of a specific material through society. All environmental interventions related to the material are inventoried. An emission evaluation indicates the dominant environmental bottlenecks, given the current market volume of each application of the material. This helps to identify improvement options and strategic choices in market portfolios. Scenario analysis on potential measures can further indicate changes of material flows — and thus markets — in the system. The approach is illustrated with a case study on chlorine.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号