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   9796篇
  免费   716篇
  国内免费   908篇
安全科学   1818篇
废物处理   196篇
环保管理   3328篇
综合类   3262篇
基础理论   1030篇
环境理论   11篇
污染及防治   587篇
评价与监测   368篇
社会与环境   525篇
灾害及防治   295篇
  2024年   17篇
  2023年   135篇
  2022年   176篇
  2021年   245篇
  2020年   330篇
  2019年   274篇
  2018年   234篇
  2017年   346篇
  2016年   447篇
  2015年   380篇
  2014年   429篇
  2013年   595篇
  2012年   619篇
  2011年   750篇
  2010年   505篇
  2009年   607篇
  2008年   438篇
  2007年   594篇
  2006年   572篇
  2005年   433篇
  2004年   452篇
  2003年   371篇
  2002年   335篇
  2001年   312篇
  2000年   320篇
  1999年   246篇
  1998年   157篇
  1997年   150篇
  1996年   119篇
  1995年   123篇
  1994年   58篇
  1993年   74篇
  1992年   65篇
  1991年   54篇
  1990年   35篇
  1989年   29篇
  1988年   37篇
  1987年   36篇
  1986年   29篇
  1985年   26篇
  1984年   27篇
  1983年   18篇
  1982年   23篇
  1981年   19篇
  1980年   26篇
  1979年   34篇
  1978年   22篇
  1977年   15篇
  1972年   17篇
  1971年   15篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
91.
On the study of ecosystem health:state of the art   总被引:2,自引:0,他引:2  
IntroductionDuringlastdecades,theterm“ecosystemhealth”isusedwithincreasingfrequencyintheliterature.Thegrowinginterestsinthestu...  相似文献   
92.
The lessons of history indicate that mismanagement of natural resources and the environment often leads to potentially adverse consequences.The increasing interest in economic development,particularly in the developing countries of the world coupled with increasing population pressures and the globalization of economic activity is placing noticeable stresses on the ultimate sustainability of both human and environmental systems.Sustainable development is not a new concept.It has been an area of concern for different elements of society for some time.Yet efforts to understand the implications of sustainable development have not,until recently,been formalized.We have focused singularly on economic development and environmental quality as if they were mutually exclusive.This paper focuses on the concept of concurrency as both a conceptual framework and practicable method of understanding and implementing the ecology and economy of sustainability.  相似文献   
93.
In this paper we deal with the problem of identifying environmental principles for the design and operation of supply chains. The operations that are included in supply chains are briefly described along with the approaches that are applied in order to improve their environmental performance. A background of environmental principles for achieving eco-efficiency and building of environmentally friendly organizational systems is presented and emphasis is put on the application of such principles “from cradle to grave”. Then, environmental principles applicable to particular objects of logistics networks planning are identified and commented upon. In addition, selective case studies from the literature, which show the applicability of the formulated principles and their relevance to practice, are discussed. The paper concludes with some remarks regarding the benefits for companies and societies, in general, that occur as a result of the application of the formulated principles.  相似文献   
94.
美国的环境立法   总被引:1,自引:0,他引:1  
通过对美国环境立法发展状况的分析,阐述了美国环境法规的特点,及其在国家加强行政环境管理等方面的作用。立法不完善,是美国环境立法的主要问题。  相似文献   
95.
介绍了世行贷款项目各阶段环境管理的具体内容和特殊问题,并提出面临难题。  相似文献   
96.
相对于传统的爆破技术,在施工场地狭小、地形陡峭以及不能影响周边居民正常工作生活秩序等条件下,运用静态爆破技术施工,具有安全、环保、简单等不可比拟的优点。笔者详细介绍了静态爆破技术的基本原理以及在长阳县榔坪中学南山坡岩崩治理中的工程实践.阐述了静态爆破技术在危岩体治理工程中的施工方法、特点,应采取的安全管理预防措施及应用推广前景。  相似文献   
97.
Numerous studies support that biodiversity predict most to ecosystem functioning, but whether other factors display a more significant direct impact on ecosystem functioning than biodiversity remains to be studied. We investigated 398 samples of the phytoplankton phosphorus resource use efficiency (RUEP = chlorophyll-a concentration/dissolved phosphate) across two seasons in nine plateau lakes in Yunnan Province, China. We identified the main contributors to phytoplankton RUEP and analyzed their potential influences on RUEP at different lake trophic states. The results showed that total nitrogen (TN) contributed the most to RUEP among the nine lakes, whereas community turnover (measured as community dissimilarity) explained the most to RUEP variation across the two seasons. Moreover, TN also influenced RUEP by affecting biodiversity. Species richness (SR), functional attribute diversity (FAD2), and dendrogram-based functional diversity (FDc) were positively correlated with RUEP in both seasons, while evenness was negatively correlated with RUEP at the end of the rainy season. We also found that the effects of biodiversity and turnover on RUEP depended on the lake trophic states. SR and FAD2 were positively correlated with RUEP in all three trophic states. Evenness showed a negative correlation with RUEP at the eutrophic and oligotrophic levels, but a positive correlation at the mesotrophic level. Turnover had a negative influence on RUEP at the eutrophic level, but a positive influence at the mesotrophic and oligotrophic levels. Overall, our results suggested that multiple factors and nutrient states need to be considered when the ecosystem functioning predictors and the biodiversity-ecosystem functioning relationships are investigated.  相似文献   
98.
主要介绍了环境保护规划在建设项目环境管理中的作用。分析了制定环境保护规划的必要性 ,提出了落实规划的相应对策  相似文献   
99.
旋流雾化水雾膜提高文丘里水膜除尘效率的实验研究   总被引:3,自引:1,他引:3  
应用低压旋流雾化水喷嘴 (不同运行压力和组合方式 )实验研究了旋流雾化水雾膜对除尘效率的影响。研究结果表明 :喉部喷嘴布置及运行情况直接影响喉部水雾均匀度和除尘效率 ;采用两两相向的低压旋流雾化水喷嘴组合布置 ,保证喷嘴入口水压力为 0 2~ 0 4MPa ,液气比为 0 1~ 0 2L/m3 时 ,除尘效率将大大提高 ,且有节水节能和脱硫效果。  相似文献   
100.
随着市场经济的迅速发展,大量厂房办公楼租赁、转让产生新类型的环境问题。由于其具有突发性、隐蔽性、难追究、治理难的特点,因而应将合同(契约)等重要经济环节纳入环境约束,加强管理,切实实施。  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