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   92809篇
  免费   1288篇
  国内免费   1297篇
安全科学   3878篇
废物处理   3381篇
环保管理   14120篇
综合类   21978篇
基础理论   26761篇
环境理论   79篇
污染及防治   15312篇
评价与监测   5519篇
社会与环境   3795篇
灾害及防治   571篇
  2022年   832篇
  2021年   846篇
  2020年   719篇
  2019年   891篇
  2018年   1202篇
  2017年   1233篇
  2016年   2245篇
  2015年   1906篇
  2014年   2663篇
  2013年   9422篇
  2012年   2348篇
  2011年   2722篇
  2010年   3388篇
  2009年   3526篇
  2008年   2211篇
  2007年   2054篇
  2006年   2394篇
  2005年   2332篇
  2004年   2648篇
  2003年   2460篇
  2002年   2023篇
  2001年   2231篇
  2000年   2005篇
  1999年   1524篇
  1998年   1390篇
  1997年   1380篇
  1996年   1500篇
  1995年   1594篇
  1994年   1491篇
  1993年   1333篇
  1992年   1316篇
  1991年   1285篇
  1990年   1245篇
  1989年   1194篇
  1988年   1041篇
  1987年   978篇
  1986年   989篇
  1985年   1068篇
  1984年   1166篇
  1983年   1165篇
  1982年   1177篇
  1981年   1101篇
  1980年   945篇
  1979年   927篇
  1978年   823篇
  1977年   722篇
  1976年   643篇
  1975年   607篇
  1973年   632篇
  1972年   637篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
42.
Journal of Material Cycles and Waste Management - The novel COVID-19 pandemic has disrupted the functioning of solid waste management globally as households experience an increase in their waste...  相似文献   
43.
Developers are often required by law to offset environmental impacts through targeted conservation actions. Most offset policies specify metrics for calculating offset requirements, usually by assessing vegetation condition. Despite widespread use, there is little evidence to support the effectiveness of vegetation-based metrics for ensuring biodiversity persistence. We compared long-term impacts of biodiversity offsetting based on area only; vegetation condition only; area × habitat suitability; and condition × habitat suitability in development and restoration simulations for the Hunter Region of New South Wales, Australia. We simulated development and subsequent offsetting through restoration within a virtual landscape, linking simulations to population viability models for 3 species. Habitat gains did not ensure species persistence. No net loss was achieved when performance of offsetting was assessed in terms of amount of habitat restored, but not when outcomes were assessed in terms of persistence. Maintenance of persistence occurred more often when impacts were avoided, giving further support to better enforce the avoidance stage of the mitigation hierarchy. When development affected areas of high habitat quality for species, persistence could not be guaranteed. Therefore, species must be more explicitly accounted for in offsets, rather than just vegetation or habitat alone. Declines due to a failure to account directly for species population dynamics and connectivity overshadowed the benefits delivered by producing large areas of high-quality habitat. Our modeling framework showed that the benefits delivered by offsets are species specific and that simple vegetation-based metrics can give misguided impressions on how well biodiversity offsets achieve no net loss.  相似文献   
44.
45.
Biomethane production through biogas upgrading is a promising renewable energy for some industries which could be part of the equilibrium needed with fossil fuels consumption to achieve a sustainable society. This paper presents a comprehensive list of biogas upgrading technologies focused on carbon dioxide removal as well as recent advances reported by researcher with wide expertise in this topic. Additionally, an extensive costs–performance comparison among the technologies studied is discussed. Among the different alternatives, chemical scrubbing stood out to achieve high biomethane purities while cryogenic technologies proved to be effective against methane losses. Regarding the different costs, water scrubbing and membrane separation seem to be the most affordable techniques.  相似文献   
46.
47.
Catastrophic disasters like earthquake and flood cause widespread destruction and financial devastation. This has brought disaster management into limelight making it a burgeoning academic research field. The remarkable rise of ICT (Information and Communication Technology) has instigated the scientific world to incorporate these technologies in disaster management. This study presents scientometric analysis to identify the status quo of research on the management of various disasters and role of ICT in it. This paper uses bibliographic data retrieved from Scopus for the observation period from 2011 to 2018. We provide extensive insights into growth of publications, citation pattern and their connectedness with other subject disciplines. Furthermore, we identify most productive and influential countries, institutes and journals. Our study analyses co-occurrence of keywords using Visualization of Similarities (VOS) Viewer. This structured overview will enhance the understanding of this field leading to more focussed and purposeful research.  相似文献   
48.
Journal of Material Cycles and Waste Management - The present research work focused on fabricating Biodegradable Plate (BD plate) composed of rice husk ash, bagasse and corn starch which is...  相似文献   
49.
50.
Quantitative methods have been applied to the study of floristic structure and diversity in Samarskaya Luka. The results show that Samarskaya Luka is a floristically heterogeneous area in which six elementary floras can be distinguished. This area has been assessed as a floristically autonomous formation, and its floristic representativeness was estimated.  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