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   104960篇
  免费   6089篇
  国内免费   29569篇
安全科学   5343篇
废物处理   3995篇
环保管理   14867篇
综合类   55625篇
基础理论   29066篇
环境理论   73篇
污染及防治   19873篇
评价与监测   6802篇
社会与环境   3629篇
灾害及防治   1345篇
  2023年   629篇
  2022年   1375篇
  2021年   1298篇
  2020年   1609篇
  2019年   3074篇
  2018年   3468篇
  2017年   3597篇
  2016年   4402篇
  2015年   4591篇
  2014年   6051篇
  2013年   13196篇
  2012年   5505篇
  2011年   5277篇
  2010年   5918篇
  2009年   6049篇
  2008年   4054篇
  2007年   3748篇
  2006年   3852篇
  2005年   3404篇
  2004年   3402篇
  2003年   3109篇
  2002年   2525篇
  2001年   2627篇
  2000年   2631篇
  1999年   2334篇
  1998年   2093篇
  1997年   2019篇
  1996年   2116篇
  1995年   2110篇
  1994年   1865篇
  1993年   1652篇
  1992年   1632篇
  1991年   1523篇
  1990年   1419篇
  1989年   1350篇
  1988年   1143篇
  1987年   1015篇
  1986年   1044篇
  1985年   1096篇
  1984年   1184篇
  1983年   1196篇
  1982年   1208篇
  1981年   1120篇
  1980年   932篇
  1979年   903篇
  1978年   813篇
  1977年   705篇
  1976年   629篇
  1973年   611篇
  1972年   615篇
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
91.
Environmental Science and Pollution Research - Suicide prevention has become a public health issue of great concern. Previous studies proved that ambient temperature had an impact on suicide death,...  相似文献   
92.
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   
93.
94.
Greenhouse gas emissions assessments for site cleanups typically quantify emissions associated with remediation and not those from contaminant biodegradation. Yet, at petroleum spill sites, these emissions can be significant, and some remedial actions can decrease this additional component of the environmental footprint. This article demonstrates an emissions assessment for a hypothetical site, using the following technologies as examples: excavation with disposal to a landfill, light nonaqueous‐phase liquid (LNAPL) recovery with and without recovered product recycling, passive bioventing, and monitored natural attenuation (MNA). While the emissions associated with remediation for LNAPL recovery are greater than the other considered alternatives, this technology is comparable to excavation when a credit associated with product recycling is counted. Passive bioventing, a green remedial alternative, has greater remedial emissions than MNA, but unlike MNA can decrease contaminant‐related emissions by converting subsurface methane to carbon dioxide. For the presented example, passive bioventing has the lowest total emissions of all technologies considered. This illustrates the value in estimating both remediation and contaminant respiration emissions for petroleum spill sites, so that the benefit of green remedial approaches can be quantified at the remedial alternatives selection stage rather than simply as best management practices. ©2015 Wiley Periodicals, Inc.  相似文献   
95.
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   
96.
97.
Environmental Science and Pollution Research - Anaerobic batch experiments were conducted to study the regulatory role of endogenous iron in greenhouse gas emissions under intensive nitrogen...  相似文献   
98.
To explore the relationships between human factors and accident proneness of coal mine workers, the depth perception, dark adaptation and vigilance abilities of 239 Chinese coal mine workers were tested and their accident proneness was surveyed with an accident proneness questionnaire. The results indicated that dark adaptation and vigilance abilities of the mine workers declined with increasing age. Vigilance had a significant negative relationship with accident proneness. There were significant differences in vigilance between coal mine workers doing different types of work. Individual difference in vigilance was relevant to the type of work that an individual did in a coal mine. The dark adaptation index had a significant positive relationship with accident proneness. Coal mine workers with weaker dark adaptation ability were also more accident prone. Some ergonomics recommendations concerning coal mine safety management in China are proposed.  相似文献   
99.
100.
建立了固定污染源排气中三氟甲烷、四氟甲烷、六氟乙烷和六氟化硫的采样和气质联用分析方法,检出限分别为0.06、0.15、0.21、0.71 mg/m3,精密度在3.2%以下,相关系数大于0.999 6,并对浙江省内2家典型企业排放的温室气体进行了监测,实际样品监测结果表明,该方法能够满足废气中4种温室气体的监测要求。  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