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   333篇
  免费   3篇
  国内免费   3篇
安全科学   9篇
废物处理   29篇
环保管理   34篇
综合类   57篇
基础理论   70篇
污染及防治   90篇
评价与监测   33篇
社会与环境   15篇
灾害及防治   2篇
  2023年   8篇
  2022年   12篇
  2021年   12篇
  2020年   8篇
  2019年   7篇
  2018年   10篇
  2017年   12篇
  2016年   15篇
  2015年   11篇
  2014年   16篇
  2013年   29篇
  2012年   22篇
  2011年   24篇
  2010年   11篇
  2009年   22篇
  2008年   10篇
  2007年   16篇
  2006年   22篇
  2005年   14篇
  2004年   16篇
  2003年   8篇
  2002年   11篇
  2000年   3篇
  1999年   3篇
  1998年   3篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1993年   1篇
  1992年   3篇
  1991年   1篇
  1990年   1篇
  1989年   1篇
  1983年   1篇
  1981年   1篇
  1977年   1篇
排序方式: 共有339条查询结果,搜索用时 171 毫秒
331.
332.
Monitoring of element flows and their mass balances in the natural unit of the biosphere represented by a small catchment appears to be the most suitable for the solution of complex problems such as the deterioration of environmental quality. Long-term collection of comparable biogeochemical data, which will enable the identification of environmental trends, is the main aim of the GEOMON network. One of the most important applications of these data will be the calculation of critical loads. The Czech Geological Survey possesses data from 44 catchments in the former Czechoslovakia. Qualitative and quantitative data on inputs in atmospheric deposition and outputs via surface runoff are available. Simple input-output mass balances yield estimates of total accumulation or loss of individual components. Some examples of interpretations of the GEOMON data, especially in connection with different bedrock types, will be given.  相似文献   
333.
This paper describes the technical and economic factors affecting rice husk residue conversion to energy. A summary of the physical and chemical characteristics is provided, with an overview of the commercially available conversion systems. An analysis of two intermediate rice residue conversion systems is included to determine the most probable fuel requirements and financial/economic costs and benefits of both systems. Recommendations are presented regarding the conditions that must be present to ensure financial viability of these systems.  相似文献   
334.
Chemical footprints left behind by true bugs are perceived as contact kairomones by scelionid egg parasitoids. Female wasps encountering a contaminated artificial substrate display a characteristic arrestment posture, holding the body motionless and antennating the surface. In the system Nezara viridula (L.) and its egg parasitoid Trissolcus basalis (Wollaston), previous studies have shown that the kairomone mediating such behavior is part of N. viridula’s cuticular hydrocarbons (CHC) and furthermore that the wasp’s ability to discriminate host male and female footprints is mainly based on the presence/absence of nonadecane (nC19). In this study, the effect of epicuticular waxes of leaves of broad bean, Vicia faba, on wasp responses to footprints of N. viridula females were investigated. Approximately 20% of T. basalis females displayed an arrestment posture when released on the adaxial leaf surfaces of broad bean plants with intact wax layer and without host chemical contamination; whereas ∼70% of wasps displayed the arrestment posture when intact leaves were contaminated by host female footprints. Adaxial leaf surfaces of broad bean plants dewaxed with an aqueous solution of gum arabic and afterwards contaminated by N. viridula females induced arrestment responses in about 10% of female wasps; the same percentage of arrestment (10%) was observed when the wasps were released on leaves contaminated by host females and subsequently dewaxed. The side of the polymer film that was appressed to the leaf surface, peeled from the contaminated leaves, induced an arrestment posture in about 95% of observed wasps. Scanning electron microscopy (SEM) revealed that the epicuticular waxes occurred as a film densely crystallized as irregularly shaped platelets with spherical granules randomly distributed. These findings demonstrated that epicuticular waxes of broad bean leaves can mediate the foraging behavior of T. basalis females by absorbing contact kairomones of the host.  相似文献   
335.
Environmental Science and Pollution Research - Occupational exposure to pesticides has been identified as a major trigger of the development of cancer. Pesticides can cause intoxication in the...  相似文献   
336.
Journal of Material Cycles and Waste Management - The construction sector is the second largest area for the application for plastics. Due to the long life times of construction products, the...  相似文献   
337.
Journal of Material Cycles and Waste Management - Detailed information about waste generation rates, composition, and their influencing factors, is essential for sustainable municipal solid waste...  相似文献   
338.
Environmental Science and Pollution Research - Devices based on lateral flow assay (LFA) have been gaining more and more space in the detection market mainly due to their simplicity, speed, and low...  相似文献   
339.
Journal of Material Cycles and Waste Management - Pyrolysis is a valid thermos-chemical process of energy production that produces biochar from potentially harmful biomasses. This study aims to...  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