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391.
A. Sirois C.L. Blanchard D.M. Whelpdale H.M. Michaels 《Atmospheric environment (Oxford, England : 1994)》1996,30(24):4115-4124
The capability of deposition networks in eastern Canada to resolve regional trends has been examined by Blanchard et al. (1996, Atmospheric Environment 30, 2539–2549). This paper extends the earlier methods to permit evaluation of the need for specific individual sites, comparison of additional network configurations, and consideration of more regions. Parameter estimates for the statistical model are improved by using monthly instead of annual data. For the regions that we examined, eliminating all provincial sites in eastern Canada would cause an increase of 1 to 6 years in the time required for reaching a 90% probabiility of detecting the expected future trends. The elimination of certain key provincial sites may increase the uncertainties in the determination of deposition isopleths of particular interest, such as the 20 kg ha−1 yr−1 contours. The statistical techniques presented here are quite general and can be extended to statistical tests or estimators other than those illustrated here. 相似文献
392.
Ekaterina Domorenok 《环境政策》2019,28(2):293-314
ABSTRACTOver the last decade, innovative governance architectures have been progressively promoted across European Union (EU) environmental and climate policies with the purpose of improving the effectiveness of intervention through better cross-sectoral policy integration and increased involvement of sub-state and non-governmental actors in the policy process. By combining the theoretical insights of polycentric governance and the concept of usage, the case of the Covenant of Mayors (CoM) is analysed to uncover the extent to which this voluntary programme has empowered local authorities within the EU strategy for sustainable energy by encouraging coordination and learning. This illustrates how a range of policy variables determined the dynamics of the programme’s implementation in Italy and the United Kingdom. 相似文献
393.
Brack W Bakker J de Deckere E Deerenberg C van Gils J Hein M Jurajda P Kooijman B Lamoree M Lek S López de Alda MJ Marcomini A Muñoz I Rattei S Segner H Thomas K von der Ohe PC Westrich B de Zwart D Schmitt-Jansen M 《Environmental science and pollution research international》2005,12(5):252-256
BACKGROUND: Triggered by the requirement of Water Framework Directive for a good ecological status for European river systems till 2015 and by still existing lacks in tools for cause identification of insufficient ecological status MODELKEY (http:// www.modelkey.org), an Integrated Project with 26 partners from 14 European countries, was started in 2005. MODELKEY is the acronym for 'Models for assessing and forecasting the impact of environmental key pollutants on freshwater and marine ecosystems and biodiversity'. The project is funded by the European Commission within the Sixth Framework Programme. OBJECTIVES: MODELKEY comprises a multidisciplinary approach aiming at developing interlinked tools for an enhanced understanding of cause-effect-relationships between insufficient ecological status and environmental pollution as causative factor and for the assessment and forecasting of the risks of key pollutants on fresh water and marine ecosystems at a river basin and adjacent marine environment scale. New modelling tools for risk assessment including generic exposure assessment models, mechanistic models of toxic effects in simplified food chains, integrated diagnostic effect models based on community patterns, predictive component effect models applying artificial neural networks and GIS-based analysis of integrated risk indexes will be developed and linked to a user-friendly decision support system for the prioritisation of risks, contamination sources and contaminated sites. APPROACH: Modelling will be closely interlinked with extensive laboratory and field investigations. Early warning strategies on the basis of sub-lethal effects in vitro and in vivo are provided and combined with fractionation and analytical tools for effect-directed analysis of key toxicants. Integrated assessment of exposure and effects on biofilms, invertebrate and fish communities linking chemical analysis in water, sediment and biota with in vitro, in vivo and community level effect analysis is designed to provide data and conceptual understanding for risk arising from key toxicants in aquatic ecosystems and will be used for verification of various modelling approaches. CONCLUSION AND PERSPECTIVE: The developed tools will be verified in case studies representing European key areas including Mediterranean, Western and Central European river basins. An end-user-directed decision support system will be provided for cost-effective tool selection and appropriate risk and site prioritisation. 相似文献
394.
本文论述了现行职称评聘制度存在的主要问题。指出了深化职称评聘制度改革的必要 性,提出了深化职称评聘制度改革的几点思考。 相似文献
395.
应用遗传神经网络方法分析我国降水化学数据 总被引:15,自引:0,他引:15
收集了111组包含Ca^2+、Mg^2+等8种离子浓度和PH值的我国降水化学数据,并用遗传神经网络(Genetic Neural Net-works,GNN)方法建立了这些离子浓度和PH值绵BP网络模式,运用这些模式计算了各离子浓度对PH值的贡献,结果表明,我国各地降水PH值与各地区酸性离子与碱性离子相互用途相关,其中生离子的中和作用起着主导作用。 相似文献
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基于贝叶斯网络的河流突发性水质污染事故风险评估 总被引:8,自引:1,他引:7
事故造成的水质突发性风险评估对于河流水质安全管理具有重要意义.通过贝叶斯网络直观地表示事故风险源和河流水质之间的相关性,并用时序蒙特卡罗算法将风险源状态模拟、水质模拟和贝叶斯网络推理过程结合,可以对多个风险源共同影响下的河流突发性水质污染事故的超标风险进行量化评估.案例研究表明,多风险源对同一受纳水体的水质突发性污染事故风险的耦合影响十分显著,在进行流域水安全管理时必须对多风险源进行综合管理.同时,模型的诊断推理功能可为流域关键风险源识别和管理提供决策支持. 相似文献