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   2014篇
  免费   49篇
  国内免费   26篇
安全科学   72篇
废物处理   125篇
环保管理   180篇
综合类   382篇
基础理论   415篇
环境理论   1篇
污染及防治   558篇
评价与监测   206篇
社会与环境   128篇
灾害及防治   22篇
  2023年   23篇
  2022年   45篇
  2021年   52篇
  2020年   30篇
  2019年   32篇
  2018年   76篇
  2017年   82篇
  2016年   93篇
  2015年   54篇
  2014年   97篇
  2013年   154篇
  2012年   97篇
  2011年   151篇
  2010年   96篇
  2009年   102篇
  2008年   104篇
  2007年   109篇
  2006年   73篇
  2005年   85篇
  2004年   79篇
  2003年   84篇
  2002年   55篇
  2001年   60篇
  2000年   38篇
  1999年   26篇
  1998年   16篇
  1997年   16篇
  1996年   8篇
  1995年   12篇
  1994年   12篇
  1993年   17篇
  1992年   17篇
  1991年   6篇
  1990年   6篇
  1989年   7篇
  1988年   7篇
  1987年   2篇
  1986年   6篇
  1985年   8篇
  1984年   4篇
  1983年   8篇
  1982年   8篇
  1981年   4篇
  1980年   2篇
  1979年   2篇
  1976年   2篇
  1972年   2篇
  1970年   2篇
  1962年   5篇
  1961年   2篇
排序方式: 共有2089条查询结果,搜索用时 187 毫秒
41.
Fire weather indices predict fire extent from meteorological conditions assuming a monotonic function; this approach is frequently used to predict future fire patterns under climate change scenarios using linear extrapolation. However, the relationship between weather and fire extent may potentially depend on the existence of fuel moisture content thresholds above which this relationship changes dramatically, challenging this statistical approach. Here, we combine the continuous and the threshold approaches to analyze satellite-detected fires in Europe during 2001–2010 in relation to meteorological conditions, showing that fire size response to decreasing fuel moisture content follows a ramp function, i.e., with two plateaus separated by a phase of monotonic increase. This study confirms that at continental and high-resolution temporal scales, large fires are very unlikely to occur under moist conditions, but it also reveals that fire size stops to be controlled by fuel moisture content above a given threshold of dryness. Thus, fuel moisture content control only applies when fire is not limited by other factors such as fuel load, as large fires were virtually absent during the considered period in dry regions with less than 500 mm of average annual precipitation, i.e., low-productive areas where fuel amount would be scarce and discontinuous. In regions with sufficient fuel, other factors such as fire suppression or fuel discontinuity can impede large fires even under very dry weather conditions. These findings are relevant under current climatic trends in which the fire season length, in terms of number of days with drought code values above the observed thresholds (break points), is increasing in many parts of the Mediterranean, while it is decreasing in eastern Europe and remains unchanged in central Europe.  相似文献   
42.
43.
Effective selective collection (SC) has been increasing in many countries of the European Union. As a consequence the composition of residual municipal solid waste (RMSW) is changing not only because of economic development, but also due to the collection system. The input of RMSW treatment plants is thus not homogeneous. This paper analyses two case studies involving a total of five SC scenarios and their impact on the generation of solid recovered fuel (SRF) with/without bio-drying, post-treatment and packaging take back programs (TBPs). These case studies are based on two types of SC: kerbside and drop-off. The latest regulation on SRF classification is taken into account: energy content, Cl and Hg concentrations are assessed and discussed. The role of the respirometric index (RI) is also analyzed. Results show that when SC is highly efficient RMSW can be classified directly as SRF, but only if the introduction of RI does not set stringent respirometric targets. The role of packaging TBPs is important as the residual waste remaining after the packaging has been processed, can be valorized increasing the lower heating value (LHV) of the residual RMSW and minimizing the streams that should be landfilled. The source separation of food waste has a significant impact on the suitability of bio-drying: when the SC of food waste is very efficient, its percentage in the RMSW may be too low for effective bio-drying.  相似文献   
44.
The use of recurrence plots have been extensively used in various fields. In this work, recurrence plots investigate the changes in the non-linear behaviour of urban air pollution using large datasets of raw data (hourly). This analysis has not been used before to extract information from large datasets for this type of non-linear problem. Two different approaches have been used to tackle this problem. The first approach is to show results according to monitoring network. The second approach is to show the results by particle type. This analysis shows the feasibility of using recurrence analysis for pollution monitoring and control.  相似文献   
45.
Regional Environmental Change - The spread of non-native species into natural communities is a noticeable phenomenon linked to global change. Drivers of such invasions, however, may differ...  相似文献   
46.
47.
48.
Environmental Geochemistry and Health - The results of a large geochemical study on various environmental media (soil, stream sediment, groundwater, surface water, lettuce and human hair) of the...  相似文献   
49.
50.
Environmental Science and Pollution Research - Dimethoate ([O,O-dimethyl S-(N-methylcarbamoylmethyl) phosphorodithioate]) is an organophosphate insecticide and acaricide widely used for...  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