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   404篇
  免费   12篇
  国内免费   2篇
安全科学   16篇
废物处理   17篇
环保管理   87篇
综合类   65篇
基础理论   105篇
污染及防治   73篇
评价与监测   36篇
社会与环境   14篇
灾害及防治   5篇
  2023年   3篇
  2021年   6篇
  2020年   4篇
  2019年   6篇
  2018年   5篇
  2017年   5篇
  2016年   19篇
  2015年   13篇
  2014年   7篇
  2013年   43篇
  2012年   19篇
  2011年   14篇
  2010年   14篇
  2009年   16篇
  2008年   14篇
  2007年   16篇
  2006年   20篇
  2005年   20篇
  2004年   7篇
  2003年   17篇
  2002年   13篇
  2001年   10篇
  2000年   8篇
  1998年   5篇
  1997年   6篇
  1996年   3篇
  1995年   4篇
  1994年   5篇
  1993年   2篇
  1992年   3篇
  1991年   7篇
  1990年   3篇
  1989年   3篇
  1988年   5篇
  1987年   7篇
  1986年   7篇
  1985年   5篇
  1984年   5篇
  1983年   5篇
  1982年   6篇
  1981年   3篇
  1980年   3篇
  1979年   3篇
  1978年   3篇
  1974年   2篇
  1971年   2篇
  1970年   2篇
  1969年   2篇
  1967年   4篇
  1953年   2篇
排序方式: 共有418条查询结果,搜索用时 0 毫秒
41.
42.
43.
The purpose of the present study was to explore whether or not flotation restricted environmental stimulation technique (REST) facilitates the creative problem-solving ability and originality. Sample 1 consisted of 40 subjects, 20 men and 20 women, randomly assigned in equal numbers to either a nonREST group (armchair-sitting) or to a floating REST group. Both groups worked on a `chain puzzle' for 5 min and were then interrupted with 45 min of sitting or floating. The subjects were then given the task of continuing with the creative problem-solving test. Sample 2 consisted of 54 subjects, 27 men and 27 women, randomly assigned in equal numbers to either a nonREST group (armchair-sitting), a dryREST group (lying on a couch in a dark room) or a flotation REST group. The groups then had to fill in a couple of paper-and-pen tests and were given scores on fluency, obvious answers, original answers, elegance and deductive thinking. The results (impaired creative problem-solving ability and higher originality for the floating group) were interpreted as an indication of cognitive function where the primary process still dominates over the secondary process.  相似文献   
44.
45.
46.
47.
A new approach was developed for Australia's 2011 national State of the Environment (SoE) report to integrate the assessment of biophysical and human elements of the environment. A Common Assessment and Reporting Framework (CARF) guided design and implementation, responding to jurisdictional complexity, outstanding natural diversity and ecosystem values, high levels of cultural and heritage diversity, and a paucity of national-scale data. The CARF provided a transparent response to the need for an independent, robust and evidence-based national SoE report. We conclude that this framework will be effective for subsequent national SoE assessments and other integrated national-scale assessments in data-poor regions.  相似文献   
48.
49.
Across the globe, groups are experimenting with initiatives to create alternatives to the dominant food system. What role might research play in helping to strengthen and multiply these initiatives? In this paper we discuss two research projects in Australia and the Philippines in which we have cultivated hybrid collectives of academic researchers, lay researchers and various non-human others with the intention of enacting community food economies. We feature three critical interactions in the “hybrid collective research method”: gathering, which brings together those who share concerns about community food economies; reassembling, in which material gathered is deliberatively rebundled to amplify particular insights; and translating, by which reassembled ideas are taken up by other collectives so they may continue to “do work”. We argue that in a climate-changing world, the hybrid collective research method fosters opportunities for a range of human and non-human participants to act in concert to build community food economies.  相似文献   
50.
We examined the effects of a commonly used preservation technique on mercury concentration in fish tissue. After fixing fish muscle tissue in formalin followed by preservation in isopropanol, we found that mercury concentration in fish muscle tissue increased by 18%, reaching an asymptote after 40 days. We used formalin–isopropanol-preserved longear sunfish (Lepomis megalotis) from the Sam Noble Oklahoma Museum of Natural History to examine historical changes and predict current mercury concentrations in fish from two rivers in southeastern Oklahoma. Glover River was free-flowing, while Mountain Fork River was impounded in 1970 and a coldwater trout fishery was established upstream from the collection site in 1989. Mercury concentrations in longear sunfish from Glover River showed no historical changes from 1963 to 2001. Mercury concentrations in longear sunfish from Mountain Fork River showed no change from 1925 to 1993 but declined significantly from 1993 to 2003. We also compared mercury concentrations of the most recently collected longear sunfish in the museum to mercury concentrations of unpreserved fish collected from the rivers in 2006. Concentrations of mercury in museum fish were not significantly different from mercury concentrations in unpreserved fish we collected from the rivers. Our study indicates that preserved museum fish specimens can be used to evaluate historical changes and predict current levels of mercury contamination in fish.  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