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   21417篇
  免费   284篇
  国内免费   175篇
安全科学   626篇
废物处理   838篇
环保管理   3217篇
综合类   4210篇
基础理论   5161篇
环境理论   15篇
污染及防治   5118篇
评价与监测   1351篇
社会与环境   1233篇
灾害及防治   107篇
  2022年   166篇
  2021年   184篇
  2020年   131篇
  2019年   174篇
  2018年   330篇
  2017年   324篇
  2016年   514篇
  2015年   374篇
  2014年   531篇
  2013年   1558篇
  2012年   637篇
  2011年   929篇
  2010年   691篇
  2009年   815篇
  2008年   910篇
  2007年   960篇
  2006年   850篇
  2005年   721篇
  2004年   722篇
  2003年   692篇
  2002年   644篇
  2001年   730篇
  2000年   496篇
  1999年   373篇
  1998年   261篇
  1997年   267篇
  1996年   293篇
  1995年   331篇
  1994年   313篇
  1993年   296篇
  1992年   253篇
  1991年   253篇
  1990年   245篇
  1989年   212篇
  1988年   203篇
  1987年   201篇
  1986年   204篇
  1985年   190篇
  1984年   231篇
  1983年   215篇
  1982年   233篇
  1981年   192篇
  1980年   169篇
  1979年   143篇
  1978年   164篇
  1977年   141篇
  1976年   120篇
  1975年   118篇
  1974年   129篇
  1971年   111篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
112.
113.
114.
115.
116.
Community mitigation of hazard impact requires hazard knowledge and preparedness on the part of the members of diverse and complex communities. Longitudinal research in the tropical cyclone prone north of Australia has gathered extensive datasets on community awareness, preparedness and knowledge, in order to contribute to education campaigns and mitigation strategies. Data have been used to identify issues of vulnerability to cyclones and capacity to deal with the hazard. This has been developed as a community vulnerability and capacity model that may be applied to diverse communities in order to assess levels of capability to mitigate and deal with the cyclone hazard. The model is presented here in a simplified form as its development is evolving and ongoing.  相似文献   
117.
Ten out of the 12 new EU members, used to belong to the so-called “former eastern block”, with a post WWII environmental policy radically different from the tendencies followed in Western Europe. The lack of conservation regulations has resulted in a rather harmful industrialization, regarding natural resources and environmental quality. While air pollution transfer is a phenomenon of transboundary level, there is a particular interest in examining the contribution of the new EU member states to the environmental pressure faced by the older member states and vice versa. The current study utilises the official data for almost 20 years published by the European Monitoring and Evaluation Program concerning the transboundary transfer of NOx and SO2 in order to analyse the situation and discuss the present and future environmental policy regarding air pollution.  相似文献   
118.
Three hundred and fifty-four women who underwent midtrimester genetic amniocentesis were matched for age, parity, indication, and smoking history, with an equivalent number of women who had declined the procedure, for the purpose of comparing the neonatal respiratory status of their offspring. There was no evidence that the infants exposed to genetic amniocentesis were compromised.  相似文献   
119.
Three different types of chromosome 12 inversion were seen in 15 individuals out of 44 individuals examined in one 8 generation family. Type 1: a pericentric inversion inv(12) (p112; q131) was found in 7 individuals and twice at prenatal diagnosis. Type 2: a paracentric inversion inv(12) (p123; p131) was seen in two individuals. Two individuals carried both inversion chromosomes, namely type 1 and type 2. The two inversion chromosomes were transmitted from each of the parents. Type 3: a double pericentric and paracentric inversion (type 3) inv(12) (p123; p131) (p112; q131) was observed in the daughter of one of the carriers of type 1 and 2 inversions and again at prenatal diagnosis in her son. The double inversion most likely arose through crossing-over in between the two inversion loops. A balanced translocation t(7; 13) and the inversion type 1 was observed in one individual, who transmitted the translocation only to an offspring. The frequency of inversions in amniotic fluid cells observed in our laboratory was 1·9 per cent. The clinical implications of these findings are discussed.  相似文献   
120.
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