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   31812篇
  免费   350篇
  国内免费   277篇
安全科学   1063篇
废物处理   1567篇
环保管理   4154篇
综合类   4832篇
基础理论   8180篇
环境理论   10篇
污染及防治   7935篇
评价与监测   2317篇
社会与环境   2183篇
灾害及防治   198篇
  2023年   150篇
  2022年   339篇
  2021年   406篇
  2020年   238篇
  2019年   280篇
  2018年   522篇
  2017年   546篇
  2016年   818篇
  2015年   585篇
  2014年   937篇
  2013年   2584篇
  2012年   1114篇
  2011年   1476篇
  2010年   1191篇
  2009年   1225篇
  2008年   1492篇
  2007年   1422篇
  2006年   1262篇
  2005年   1170篇
  2004年   1176篇
  2003年   1110篇
  2002年   1005篇
  2001年   1144篇
  2000年   785篇
  1999年   508篇
  1998年   374篇
  1997年   397篇
  1996年   408篇
  1995年   476篇
  1994年   403篇
  1993年   349篇
  1992年   383篇
  1991年   365篇
  1990年   332篇
  1989年   329篇
  1988年   298篇
  1987年   249篇
  1986年   250篇
  1985年   254篇
  1984年   276篇
  1983年   261篇
  1982年   271篇
  1981年   227篇
  1980年   165篇
  1979年   188篇
  1978年   164篇
  1977年   134篇
  1975年   138篇
  1973年   167篇
  1972年   143篇
排序方式: 共有10000条查询结果,搜索用时 125 毫秒
121.
Environment, Development and Sustainability - Realisation of the sustainable development goals (SDGs) will provide improvements to people's lives and longevity of the planet. The architectural,...  相似文献   
122.
Russian Journal of Ecology - Populations at the border of ranges are considered more vulnerable than those in the center. However, some recent reviews contradict this hypothesis. We have studied...  相似文献   
123.
Russian Journal of Ecology - Abstract—We tested a hypothesis about the different abilities of alien and native plants to form arbuscular mycorrhizae. The studies were carried out in the...  相似文献   
124.
125.
126.
Two chromium removal experiments were performed in bioreactors with and without a magnetic field under the same conditions.The release of the chromium present in the biomass was tested in two experiments one with the initial pH of the medium and one with pH 4.0.The objective was to remove Cr(Ⅵ) and total Cr from the effluent,this was carried out by placing biological treatments of synthetic effluent contaminated with 100 mg/L of Cr(Ⅵ) in a bioreactor with neodymium magnets that applied a magnetic field(intensity85.4 mT) to the mixed culture.The removal of Cr(Ⅵ) was approximately 100.0% for the bioreactor with a magnetic field and 93,3% for the bioreactor without a magnetic field for9 hr of recirculation of the synthetic effluent by the bioreactor.The removal of total Cr was61.6% and 48.4%,with and without a magnetic field,respectively;for 24 hr.The desorption of Cr(VI) in the synthetic effluent was 0.05 mg/L,which is below the limit established by Brazilian legislation(0.1 mg/L) for the discharge of effluent containing Cr(Ⅵ) into bodies of water.The results obtained for the removal of chromium in synthetic effluent suggested that there was no significant influence on the viable cell count of the mixed culture.The desorption of Cr(Ⅵ) in synthetic effluent after bioadsorption of chromium by the mixed culture in the process of removal of chromium in bioreactors with and without a magnetic field was not significant in either of the experiments with different initial pHs.  相似文献   
127.

This article aims to evaluate municipal solid waste (MSW) management schemes in order to promote sustainability and eco-efficiency, core elements in global mitigation strategies in both public and private policies. A discrete event simulation (DES) approach was used to integrate the economic, environmental, and social aspects related to aseptic carton packages (ACP) in Itajuba, Brazil. The simulated scenarios consider three alternatives for disposing ACP: landfills, recycling, and incineration with energy recovery. According to our findings, incineration alternatives are preferred from an eco-efficiency perspective, given the potential greenhouse gas (GHG) emissions reductions and due to the possibility of energy recover, which reinforces the contribution of this technology to promote sustainability as largely found in the international literature. Given the context of MSW management in Brazil, this represents a significant opportunity to increase the effectiveness of mitigation strategies adopted in the country. Taking into account that this is by far the least applied technology, the authors strongly advocate that global strategies for mitigation consider different approaches to integrate carbon dioxide (CO2) emission reductions related to the entire MSW management system and its alternatives, thus advancing from a waste disposal-oriented system to a life cycle–oriented system.

  相似文献   
128.
Advanced oxidation technologies are a friendly environmental approach for the remediation of industrial wastewaters. Here, one pot synthesis of mesoporous WO_3 and WO_3-graphene oxide(GO) nanocomposites has been performed through the sol–gel method. Then, platinum(Pt) nanoparticles were deposited onto the WO_3 and WO_3-GO nanocomposite through photochemical reduction to produce mesoporous Pt/WO_3 and Pt/WO_3-GO nanocomposites. X-ray diffraction(XRD) findings exhibit a formation of monoclinic and triclinic WO_3 phases. Transmission Electron Microscope(TEM) images of Pt/WO_3-GO nanocomposites exhibited that WO_3 nanoparticles are obviously agglomerated and the particle sizes of Pt and WO_3 are ~ 10 nm and 20–50 nm, respectively. The mesoporous Pt/WO_3 and Pt/WO_3-GO nanocomposites were assessed for photocatalytic degradation of Methylene Blue(MB) as a probe molecule under visible light illumination.The findings showed that mesoporous Pt/WO_3, WO_3-GO and Pt/WO_3-GO nanocomposites exhibited much higher photocatalytic efficiencies than the pure WO_3. The photodegradation rates by mesoporous Pt/WO_3-GO nanocomposites are 3, 2 and 1.15 times greater than those by mesoporous WO_3, WO_3-GO, and Pt/WO_3, respectively. The key factors of the enhanced photocatalytic performance of Pt/WO_3-GO nanocomposites could be explained by the highly freedom electron transfer through the synergetic effect between WO_3 and GO sheets, in addition to the Pt nanoparticles that act as active sites for O2 reduction, which suppresses the electron hole pair recombination in the Pt/WO_3-GO nanocomposites.  相似文献   
129.
130.
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