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   521篇
  免费   1篇
安全科学   9篇
废物处理   40篇
环保管理   25篇
综合类   73篇
基础理论   110篇
污染及防治   187篇
评价与监测   59篇
社会与环境   19篇
  2023年   6篇
  2022年   18篇
  2021年   12篇
  2020年   4篇
  2019年   8篇
  2018年   21篇
  2017年   18篇
  2016年   30篇
  2015年   14篇
  2014年   38篇
  2013年   71篇
  2012年   35篇
  2011年   39篇
  2010年   27篇
  2009年   19篇
  2008年   14篇
  2007年   17篇
  2006年   22篇
  2005年   7篇
  2004年   4篇
  2003年   6篇
  2002年   5篇
  2001年   2篇
  2000年   4篇
  1997年   2篇
  1996年   2篇
  1995年   3篇
  1994年   2篇
  1993年   2篇
  1990年   3篇
  1986年   2篇
  1984年   2篇
  1982年   2篇
  1980年   2篇
  1971年   2篇
  1970年   7篇
  1969年   2篇
  1967年   5篇
  1966年   3篇
  1965年   2篇
  1964年   1篇
  1961年   1篇
  1960年   4篇
  1959年   4篇
  1958年   10篇
  1957年   4篇
  1956年   3篇
  1955年   1篇
  1931年   1篇
  1930年   1篇
排序方式: 共有522条查询结果,搜索用时 15 毫秒
31.
This paper introduces a model, which is enabling a comparison between universities regarding research, educational and environmental performances; the mission of university fits the sustainability idea. The purpose of the paper is to improve the methodology and indicators of the existing ranking tables. The three dimensional index, which provides simplified information about the quality of universities, has been developed. It enables quick detection of the weaknesses, strengths and opportunities for universities. Weights of indicators were determined using the analytic hierarchy process (AHP). Results of the AHP have shown that the most important are research oriented indicators, followed by social and environmental ones.The proposed model has been tested on a sample of 35 top universities from the ARWU (Academic Ranking of World Universities) and Times ranking tables and a new ranking table – the Three dimensional University Ranking (TUR) has been developed. In addition, correlations between indicators and ranking tables have been carried out. There is only a medium correlation between the ARWU and TUR. Regarding the indicators, a high correlation with Hirsch indices and Highly Cited Researchers exists, while there is an insignificant correlation between the low student to staff ratio and the graduation rate.  相似文献   
32.
Concentrations of Ag, Al, Ba, Cd, Co, Cr, Cu, Fe, K, Mn, Na, Ni, Pb, Sr, and Zn—isolated by sequential extraction steps from apple orchard soil—were analyzed by inductively coupled plasma-atomic emission spectroscopy and compared to the total amount of metal in soil determined by XRF. The extractable amount of each metal was calculated by the extraction yields of the four steps. The LODs of the different elements in all extracts ware below 3 μg/L except for Ba (steps 1 and 2), Cu (step 1), Fe (all steps), K (steps 1–3), Mn (step 2), Na (steps 1–3), Ni (step 1), Pb (steps 1 and 4), and Zn (steps 1 and 2). The highest LOD (>10 μg/L) was found for Fe, K, and Na (step 1). The recovery of all metals after four sequential extraction steps was 90–112%. The repeatability (<1.1%), the intermediate precision (<5.3%), the day-to-day reproducibility (<6.2%), and the overall uncertainty of measurement (approximately 4–8.5%) for all analyzed metals supports the choice of the method used.  相似文献   
33.
Journal of Material Cycles and Waste Management - This work focuses on the issue of emergency prevention in the operation of municipal solid waste landfills. In this work, an emergency is...  相似文献   
34.
35.
36.
37.
Environmental Geochemistry and Health - Extreme flooding in May, 2014 affected the sub-catchments of six major rivers in Serbia. The goal of the study was to evaluate the contents of potentially...  相似文献   
38.
39.
40.
The Strait of Otranto is the connection between the Adriatic and Ionian Seas. Low nutrient concentrations, high transparency, and low phytoplankton cell density and biomass reflect the oligotrophic character of the area. Enrichment of the euphotic layer with nutrients is mainly due to discharge of Albanian and Greek rivers, as well as mixing and upwelling in winter/early spring. Following phytoplankton bloom in April, a progressive decrease of phytoplankton cell density is due to the consumption of nutrients throughout the proceeding summer and autumn. Nitrogen was a strong limiting factor for phytoplankton growth in summer. Deep biomass maxima were detected in the 50 to 100 m layer and corresponded mostly to cells smaller than 20 m. The eastern part of the strait is mostly influenced by the northerly inflowing current from the Ionian Sea, and the western part by the southerly outflowing current from the Adriatic Sea. This typical circulation could be disturbed by inertial oscillations in the current field, generated by the strong oscillating winds and cyclonic eddies. The type of circulation determined the distribution of thermohaline characteristics, abundance, biomass, as well as taxonomic composition of phytoplankton, across the strait. Ecological characteristics of the water masses on two sides of the strait were significantly different during the formation of a longitudinal thermohaline front in May 1990.  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