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311.
Regionalairqualitypredictionmodelsusingtheknowledge-basedsystemapproachDuMin;BaiNaibin;YaoGuian(ResearchcenterforEco-Environm...  相似文献   
312.
浅述天津十一五、十二五期间主要污染物总量控制的工作历程,总结实践经验并对现有问题进行反思,梳理未来几年减排工作方法和管理策略。在此基础,提出采用提升排放标准和差别化征收排污费等手段确保总量控制制度的有效实施。  相似文献   
313.
明晰生态补偿的价值目标,既是健全我国生态补偿政策体系、体现公共政策属性的关键,也是调动各方生态保护积极性、提升自然生态系统稳定性与生态产品供给能力的现实需要。本文首先评述了关于生态补偿价值目标的研究进展,认为国内对该领域的研究比较欠缺,亟须补充;其次对于国际上生态补偿的价值目标选择,从维护和提升生态系统服务功能、农民减贫脱贫、推动城乡生态公正以及提高农民生态参与意识等四个方面进行了介绍。反思国内生态补偿价值目标的问题,本文提出生态补偿机制完善与价值目标导向:①以“绿水青山就是金山银山”理念面向多元价值目标构建生态补偿机制;②通过生态补偿机制建设提升生态系统服务功能;③通过生态补偿机制接续推进全面脱贫与乡村振兴的有效衔接;④通过生态补偿机制建设促进城乡生态公正;⑤加强生态补偿政策宣传激发公民生态意识。  相似文献   
314.
应用基于案例推理技术研究了某新型防空导弹的故障诊断问题。在对原理进行介绍的基础上,采用CBR的知识表示方法及推理机制等建立了故障诊断专家系统,给出了诊断实例,使导弹武器系统的诊断推理保证了高效率和高质量。  相似文献   
315.
江苏省各级环境监测站创建国家标准化站的经验及体会   总被引:1,自引:0,他引:1  
介绍了江苏省各级环境监测站在创建国家标准化站过程中的主要做法及取得的经验,根据个人的体会对创建中存在的问题提出了相应的建议。  相似文献   
316.
可再生能源发电配额制政策(RPS)研究   总被引:12,自引:0,他引:12  
本文首先解释了可再生能源发电配额制政策的基本含义。然后 ,通过比较英国、美国、荷兰、丹麦和澳大利亚五国的可再生能源发电配额制政策 ,总结了实施RPS的国际经验 ,包括成功的经验和失败的教训 ,提出了以及对中国实施RPS的政策建议  相似文献   
317.
Animals obtain information from past foraging experience to adjust their foraging activity according to their environment. The ability of spiders to obtain information from unsuccessful predation experiences was investigated by examining the effects on web building, a significant foraging investment, of prey detection without successful capture in the orb-web spider Cyclosa octotuberculata. Four treatments were employed: (1) successful capture and feeding: one syrphid fly was allowed to be captured and consumed by the spider on the web; (2) single prey-item detection: a syrphid fly was placed on the web to lure the spider, but was removed before capture; (3) five prey-item detection: above prey-item detection stimulus was given five times; and, (4) control: neither prey nor feeding on the web. While control spiders decreased the total thread length and capture area of their webs, prey-item detection spiders in both conditions increased them, indicating that the spider obtained information from unsuccessful predation experience to adjust their foraging investment. The fed spiders exhibited a significantly greater increase than the prey-detection-only spiders, suggesting that prey detection alone and prey detection with consumption had different informational effects. Total thread length did not differ between single and five prey-item detection spiders, but distance between two adjacent sticky spirals increased only in the former spiders, possibly because five times unsuccessful predations prevented spiders to reduce web stickiness. It suggests that the spider changed web morphology according to the number of prey detection.  相似文献   
318.
Lake eutrophication (LE) has become an increasingly severe environmental problem recently. However, there has been no nutrient standard established for LE control in many developing countries such as China. This study proposes a structural equation model to assist in the establishment of a lake nutrient standard for drinking water sources in Yunnan-Guizhou Plateau Ecoregion (Yungui Ecoregion), China. The modeling results indicate that the most predictive indicator for designated use-attainment is total phosphorus (TP) (total effect =-0.43), and chlorophyll a (Chl-a) is recommended as the second important indicator (total effect =-0.41). The model is further used for estimating the probability of use-attainment associated with lake water as a drinking water source and various levels of candidate criteria (based on the reference conditions and the current environmental quality standards for surface water). It is found that these candidate criteria cannot satisfy the designated 100% use-attainment. To achieve the short-term target (85% attainment of the designated use), TP and Chl-a values ought to be less than 0.02 mg/L and 1.4 μg/L, respectively. When used as a long-term target (90% or greater attainment of the designated use), the TP and Chl-a values are suggested to be less than 0.018 mg/L and 1 μg/L, respectively.  相似文献   
319.
This article addresses methodological issues of the human reliability analysis (HRA) in the context of probabilistic safety studies. Several conventional HRA techniques, more often used for the evaluation of the human error probabilities (HEPs), have been classified. A taxonomy of human actions, failure events, and related factors is outlined in order to distinguish action phases, human behavior types and incorrect outputs (errors of omission or commission), error types (slips, lapses, and mistakes), and performance-shaping factors (PSFs) influencing the human performance. A tree is proposed to facilitate the selection of a specific method for the evaluation of human reliability with regard to attributes of the situation analyzed. A software system based on the expert system technology to facilitate and document PSA and HRA is outlined. At the end of the article some research challenges in the domain are discussed.  相似文献   
320.
空场法开采的矿山,往往留下大面积的采空区,易发生渐进式倒塌的整体性破坏.针对大量不规则点柱支撑顶板的复杂采空区结构,采用Voronoi图形划分方法确定顶板荷载面积,在此基础上提出了模拟矿柱破坏、荷载转移、应力重新分布过程的计算方法及其适用性.以浙江长兴白象硅灰石矿采空区结构为案例,进行了计算验证,圈定了潜在的采空塌陷区范围,并从理论上提出了控制采空区大面积塌陷的对策.该方法对于该类型矿山的采空区地压控制具有指导意义.  相似文献   
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