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   262篇
  免费   4篇
  国内免费   7篇
安全科学   64篇
废物处理   2篇
环保管理   47篇
综合类   67篇
基础理论   24篇
污染及防治   15篇
评价与监测   47篇
社会与环境   5篇
灾害及防治   2篇
  2023年   7篇
  2022年   1篇
  2021年   12篇
  2020年   12篇
  2019年   2篇
  2018年   5篇
  2017年   7篇
  2016年   9篇
  2015年   14篇
  2014年   21篇
  2013年   12篇
  2012年   7篇
  2011年   23篇
  2010年   8篇
  2009年   18篇
  2008年   17篇
  2007年   9篇
  2006年   13篇
  2005年   10篇
  2004年   4篇
  2003年   7篇
  2002年   7篇
  2001年   6篇
  2000年   6篇
  1999年   3篇
  1998年   4篇
  1997年   8篇
  1996年   4篇
  1994年   1篇
  1993年   2篇
  1992年   2篇
  1991年   1篇
  1989年   2篇
  1987年   2篇
  1986年   3篇
  1983年   1篇
  1979年   2篇
  1968年   1篇
排序方式: 共有273条查询结果,搜索用时 187 毫秒
131.
In the context of a study by the International Geomechanical Commission (IGC) and the International Atomic Energy Agency (IAEA) on the effects of nuclear tests at the atolls of Mururoa and Fangataufa, release to the biosphere is estimated for 35 radionuclides originating from 147 nuclear underground tests. Based on a qualitatively characterised hydrogeological situation of atolls and relatively scarce site-specific data, a model chain was developed to conservatively estimate the radionuclide fluxes via groundwater, from their sources, the explosion cavities, towards the biosphere, the ocean or lagoon.Finite element hydro-thermal modelling was used to describe water flow. Parameters were calibrated by a very few measured pre-test temperature profiles in bore holes. The impact of the tests on groundwater flow and mechanical impact on rock was considered. Estimates were made to quantify spatial extensions and temporal evolution of impact by using measurements on refilling rate of the cavities. Tests were categorised according to their specific yield and location although detailed data were missing. A base case parameter set was defined for the hydraulic conditions and for the initial radionuclide inventory of individual tests. Models were used to describe the concentration of radionuclides in the cavities as a function of time. Radionuclide transport from the cavities to the biosphere was represented by two different approaches: a double porosity model for the fractured volcanic rock and a single porosity model for the overlaying, highly porous carbonates. Results consist of conservative estimates on radionuclide release into the environment, or concentration in the lagoon or ocean water. Their sensitivity was investigated using different models and parameters. A few measured data (concentrations in a few cavities, in the deep carbonates and in the lagoons for selected radionuclides, such as 3H, 14C, 36Cl, 90Sr, 129I, 137Cs239, 240Pu and 241Am) were available for a comparison with the calculations. In view of the lack and uncertainty of site-specific data, the agreement is of acceptable quality.  相似文献   
132.
133.
海南省环境质量与经济发展DEA有效性评价   总被引:2,自引:0,他引:2  
以海南省环境质量作为研究对象,结合海南经济发展的现状构建评价指标体系,运用DEA模型对海南省环境质量与经济发展有效性进行评价。结果表明,DEA的有效性与地区经济的发展水平紧密相关,DEA有效性与经济发展好坏基本一致;部分区域的环境污染物排放集中与转移,实现了经济与环境发展协调的DEA有效。在此基础上,对DEA无效的背后因素做了进一步分析,提出提升资源利用效率和优化经济结构才是实现环境质量与经济协调发展的根本途径。  相似文献   
134.
The issue of municipal solid waste (MSW) arisings has received great attention recently since it is not only a by-product of economic activity but also serves as an input to the economy through material or energy recovery. The main focus of this study is cultural formation and especially the current picture of waste culture and public perception across European Union (EU) member states. Thus, this study will first evaluate environmental efficiency with data envelopment analysis (DEA) based on five parameters: waste, gross domestic product (GDP), labour, capital, and population density for 22 EU Member States and for the years 2005, 2010 and 2015 in order to evaluate which Member States are more efficient. Then the efficiency results are contrasted to Hofstede’s and Schwartz’s cultural dimensions on STATA with the use of regression modelling. Results show that for year 2005 no significant relationship is noticed for both cultural models, whereas for years 2010 and 2015 there appears to be a significant connection. The above-mentioned findings can be associated with the financial crisis that has hit Europe after 2008 making people more sceptical, while EU legislations have laid out some important directives in the field of waste management. Finally, along with the factors above, EU has faced severe environmental challenges due to waste arisings, as well as accidents and injuries for people working in this sector, which in turn have widely modified EU’s waste culture as supported by this study’s results.  相似文献   
135.
/ An exhaustive search of the literature for foot and vehicle traffic impacts on vegetation has yielded more than 400 citations, two thirds of which held sufficient detail to be usefully distilled into a personal-computer data base. A total of 1444 individual observations involving 737 species that were trampled are included. Compromises were made in the depth of entry detail and to allow comparability among data. Inconsistent, generally short-term, experimental practices disallowed formal statistical analyses. Within those constraints, graminoids emerged with the highest mean resistance and resilience among life-forms. Climbers and cactoids ranked lowest in these categories. The herbaceous, typically broader-leaved (forb) life-form appeared most likely to suffer immediate losses. Shrubs and trees had the longest-lasting decreases in diversity following traffic impact. All life-forms had sensitive species. The greatest general species and individual plant losses take place in the first few passes by feet, wheels, or tracks. Plant and soil damage increases with the amount of weight and power applied. Greater soil moisture and/or deeper overstory shading magnify those impacts. Additional precepts may become apparent to data-base users through increased ease in making comparisons.KEY WORDS: Vegetation; Trampling; Vehicles; Traffic; Resistance; Resilience; Data base  相似文献   
136.
The paper outlines the emerging effects of the Information Technological revolution and examines the likely consequences for planning in Britain. A number of possible scenarios are described as a basis for thinking about the design of a new planning system for the future.  相似文献   
137.
A technicoeconomic model is developed to select an optimal strategy for the remediation of a contaminated site and to determine the value of this remediation strategy. The model is an extension of actual cost–benefit analysis, with consideration of “irreversible” remediation technology choices, technology effectiveness, and uncertainty on the site's level of contamination. The model considers the possibility of reducing uncertainty by both acquiring more and better information on the level of contamination and by offering the decision-maker the opportunity to reevaluate his decision and switch to a more appropriate technology. It is believed that this model will help decision-makers in the selection of a remediation strategy by presenting all potentially feasible strategies, and how uncertainty on the site's level of contamination affects these strategies.  相似文献   
138.
基于GIS工业危险源和隐患控制及应急调控技术的应用研究   总被引:6,自引:6,他引:6  
笔者把面向对象方法及地理信息系统 (GIS)的技术应用于工业危险源与隐患控制及其应急调控技术中。介绍了面向对象的工业危险源、隐患控制及应急调控地理信息系统的功能、特点、开发环境以及设计与系统实现 ,旨在研究和探索更加完善和科学的现代化安全管理模式  相似文献   
139.
试论环境监测数据审核   总被引:3,自引:0,他引:3  
朱广一 《四川环境》2004,23(3):56-57
环境监测数据的审核,是质量保证工作的重要环节。文章联系工作实际,指出应从数据的原始性、检测的规范性、检测的时效性、数据的合格性和信息的完整性等方面对数据进行审核。在数据审核中应考虑数据的客观规律和污染指标的关联性。  相似文献   
140.
Environmental programs have been commonly driven by a preoccupation with the collection of data in the mistaken belief thatdata is synonymous withinformation. The distinction between data (that is, the quantified and qualitative attributes of a particular environment) and information (specifically, data processed so as to focus upon a particular environmental problem) will become far more important to environmental managers. They will increasingly manage their information through use of what has become known as information resource management (IRM) and the attendant use of critical success factors methodology. Environmental managers will thereby move away from concerns about data and specific EDP hardware and applications toward managing information as a valuable agency resource. In applying IRM, they will find it helpful to include a number of planning elements and to resolve early a number of issues critical to its successful use.  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