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   35369篇
  免费   391篇
  国内免费   489篇
安全科学   1089篇
废物处理   1701篇
环保管理   4049篇
综合类   5847篇
基础理论   9109篇
环境理论   25篇
污染及防治   9669篇
评价与监测   2497篇
社会与环境   2065篇
灾害及防治   198篇
  2023年   184篇
  2022年   458篇
  2021年   469篇
  2020年   316篇
  2019年   388篇
  2018年   674篇
  2017年   700篇
  2016年   998篇
  2015年   752篇
  2014年   1157篇
  2013年   2840篇
  2012年   1375篇
  2011年   1792篇
  2010年   1407篇
  2009年   1402篇
  2008年   1715篇
  2007年   1731篇
  2006年   1468篇
  2005年   1254篇
  2004年   1158篇
  2003年   1208篇
  2002年   1064篇
  2001年   1295篇
  2000年   893篇
  1999年   555篇
  1998年   370篇
  1997年   377篇
  1996年   374篇
  1995年   449篇
  1994年   471篇
  1993年   361篇
  1992年   392篇
  1991年   366篇
  1990年   398篇
  1989年   354篇
  1988年   304篇
  1987年   282篇
  1986年   240篇
  1985年   258篇
  1984年   273篇
  1983年   265篇
  1982年   255篇
  1981年   227篇
  1980年   183篇
  1979年   199篇
  1978年   181篇
  1976年   122篇
  1975年   145篇
  1972年   137篇
  1971年   133篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.

Natural products may be applied in a wide range of domains, from agriculture to food and pharmaceutical industries. In this study, the antioxidant properties and the capacity to inhibit some enzymatic activities of Euphorbia resinifera and Euphorbia officinarum aqueous extracts and honeys were assessed. The physicochemical characteristics were also evaluated. Higher amounts of iron, copper and aluminium were detected in E. officinarum honey, which may indicate environmental pollution around the beehives or inadequate storage of honey samples. This honey sample showed higher amounts of total phenols and better capacity for scavenging superoxide anion free radicals and DPPH free radicals as compared with E. resinifera honey, but poorer capacity for inhibiting lipoxygenase, acetylcholinesterase, tyrosinase and xanthine oxidase. The ratio plant mass:solvent volume (1:100) and extraction time (1 - 2 h) were associated with higher total phenols and better antioxidant activities and lipoxygenase, acetylcholinesterase and tyrosinase inhibitory activities, regardless of the plant species. The aqueous extracts had systematically higher in vitro activities than the respective honey samples.

  相似文献   
993.
Environmental Science and Pollution Research - We studied the removal of 61 emerging micropollutants, including illicit drugs, in a biofilter wastewater treatment plant located in the French Indies...  相似文献   
994.
Environmental Science and Pollution Research - Air and water quality in urban centers are summited to pollution from different sources, such as industrial activities, traffic, and wastewater...  相似文献   
995.
Environmental Science and Pollution Research - The impact of uncontrolled municipal dumping sites on metal contamination in the surrounding waters, sediments, and soils are of great concern in many...  相似文献   
996.
Environmental Science and Pollution Research - For a long time, limestone has been massively used in stone building and monuments because of its easy extraction and common presence in the...  相似文献   
997.
Environmental Science and Pollution Research - Phytoremediation techniques have been proposed as ecological methods to clean up contaminated sites. This study is aimed to evaluate the effect of the...  相似文献   
998.
Environmental Science and Pollution Research - Water contamination is a common problem, especially considering dyes and drugs disposal. A possible and effective treatment method to remove these...  相似文献   
999.
Environmental Science and Pollution Research - This work studies the effects of different bromide-based ionic liquids, with phosphonium and ammonium cations, towards several environmental...  相似文献   
1000.
Environmental Science and Pollution Research - Residential settings are of utmost importance for human exposure, as it is where people spend most of their time. Residential wood combustion is a...  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