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   2893篇
  免费   186篇
  国内免费   1267篇
安全科学   228篇
废物处理   173篇
环保管理   196篇
综合类   1801篇
基础理论   528篇
污染及防治   1046篇
评价与监测   161篇
社会与环境   95篇
灾害及防治   118篇
  2024年   7篇
  2023年   65篇
  2022年   176篇
  2021年   136篇
  2020年   127篇
  2019年   106篇
  2018年   130篇
  2017年   142篇
  2016年   164篇
  2015年   176篇
  2014年   261篇
  2013年   321篇
  2012年   264篇
  2011年   245篇
  2010年   199篇
  2009年   196篇
  2008年   221篇
  2007年   191篇
  2006年   161篇
  2005年   129篇
  2004年   89篇
  2003年   102篇
  2002年   86篇
  2001年   93篇
  2000年   79篇
  1999年   89篇
  1998年   69篇
  1997年   46篇
  1996年   45篇
  1995年   64篇
  1994年   42篇
  1993年   35篇
  1992年   25篇
  1991年   21篇
  1990年   9篇
  1989年   10篇
  1988年   6篇
  1987年   6篇
  1986年   5篇
  1985年   1篇
  1983年   2篇
  1982年   3篇
  1976年   1篇
  1972年   1篇
排序方式: 共有4346条查询结果,搜索用时 62 毫秒
981.
Circular economy (CE) focuses on resource-productivity and eco-efficiency improvement in a comprehensive way, especially on the industrial structure optimization of new technology development and application, equipment renewal and management renovation. The leather industry on the one side boosts the local economic development, on the other side however leads to the tremendous environment pollution and biological chains destruction. The CE model has been implemented as a new way of raw materials, water and energy consumption reduction in the leather industry. Reduce, Reuse, Recycle and Recover of the tannery effluents have been discussed in detail according to the different operation processes. The successful treatment approaches with analysis in the aspects such as wastewater, solid waste, sulfide, Chemical Oxygen Demand (COD), ammonium salt, chloride and chrome of the leather tannery with CE model provide guidance for the sustainable development of leather industry in the future.  相似文献   
982.
This paper uses the gravity model to examine the effect of environmental regulations on pork trade flows between different regions within China.We apply a linear programming tool to estimate pork trade flows from 2000 to 2008,and discuss the environmental acts on livestock pollution and income level to proxy environmental regulations.We use OLS regression and panel data with dummy variable in the cross-sectional GLS estimation.Our results indicate that the gap of environmental regulations between trade partners has a positive relationship with pork trade flows,and the difference in environmental regulations changes the traditional comparative advantage pattern to some extent.This paper provides convincing evidence for the pollution haven effect on livestock in China.  相似文献   
983.
Environmental Science and Pollution Research - Sediments are reservoirs and sources of DDTs to the aquatic ecosystem. However, the role of sediment particulate matter and benthic organisms in...  相似文献   
984.
Environmental Science and Pollution Research - Haze pollution may decrease drivers’ driving performance by worsening their physical and psychological states. This paper explores the effects...  相似文献   
985.
986.
Plastics from waste electrical and electronic equipment (WEEE) have been an important environmental problem because these plastics commonly contain toxic halogenated flame retardants which may cause serious environmental pollution, especially the formation of carcinogenic substances polybrominated dibenzo dioxins/furans (PBDD/Fs), during treat process of these plastics. Pyrolysis has been proposed as a viable processing route for recycling the organic compounds in WEEE plastics into fuels and chemical feedstock. However, dehalogenation procedures are also necessary during treat process, because the oils collected in single pyrolysis process may contain numerous halogenated organic compounds, which would detrimentally impact the reuse of these pyrolysis oils. Currently, dehalogenation has become a significant topic in recycling of WEEE plastics by pyrolysis. In order to fulfill the better resource utilization of the WEEE plastics, the compositions, characteristics and dehalogenation methods during the pyrolysis recycling process of WEEE plastics were reviewed in this paper. Dehalogenation and the decomposition or pyrolysis of WEEE plastics can be carried out simultaneously or successively. It could be ‘dehalogenating prior to pyrolysing plastics’, ‘performing dehalogenation and pyrolysis at the same time’ or ‘pyrolysing plastics first then upgrading pyrolysis oils’. The first strategy essentially is the two-stage pyrolysis with the release of halogen hydrides at low pyrolysis temperature region which is separate from the decomposition of polymer matrixes, thus obtaining halogenated free oil products. The second strategy is the most common method. Zeolite or other type of catalyst can be used in the pyrolysis process for removing organohalogens. The third strategy separate pyrolysis and dehalogenation of WEEE plastics, which can, to some degree, avoid the problem of oil value decline due to the use of catalyst, but obviously, this strategy may increase the cost of whole recycling process.  相似文献   
987.
988.
为了提高选择性催化还原(SCR)在低温区(200℃)的脱硝性能,提出利用插在烟道中的沿面放电反应器生成氧活性物质,部分氧化NO以实现低温快速SCR脱硝过程.同时,研究了氧活性物质注入实现快速SCR的脱硝性能,考察了氧活性物质注入降低二氧化硫和水蒸汽对SCR反应的影响.实验结果表明:在模拟烟气温度为150℃时,采用氧活性物质注入,部分氧化烟气中的NO以实现快速SCR反应条件下(NO/NO2浓度比为1),脱硝效率为51.9%,比标准SCR提升23%;当模拟烟气中存在SO2或H2O时,氧活性物质注入可有效降低SO2、H2O对SCR脱硝效率的影响.  相似文献   
989.
以Ti-SnO2电极作为阴阳极,利用电解池对焦化厂熄焦循环水COD进行去除。极板间距为1 cm,6个极片组成电解池,处理熄焦循环水。实验结果表明:废水被稀释1倍时,污染物的浓度有利于COD的去除;最佳去除条件是电解电压为11 V,p H值为6;当电解时间为0.5 h时,废水的COD由230 mg/L降低到138 mg/L,满足《炼焦化学工业污染物排放标准》中规定的焦化生产废水经处理后用于熄焦时对COD的要求;电解时间增加到2 h,废水的COD由230 mg/L降低到66 mg/L,去除率达到80%。  相似文献   
990.
Surface acting has been widely studied in organizational research owing to its impact on organizational behaviors and outcomes. Past research almost exclusively has focused on employees' interactions with external parties such as customers, clients, and patients. This study sought to extend this literature by examining the effects of employees' surface acting in interactions with parties internal to the organization (i.e., leaders and peers). Data were collected from 40 work groups (129 focal participants, 40 leaders, and 40 peers) from a large real estate agency company located in Beijing, China. Results showed that employees' surface acting influenced various emotional, relational, and behavioral outcomes. In addition, the present findings revealed that the consequences of employees' surface acting differed across leaders versus peers. Copyright © 2015 John Wiley & Sons, Ltd.  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