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   1858篇
  免费   154篇
  国内免费   141篇
安全科学   467篇
废物处理   39篇
环保管理   356篇
综合类   709篇
基础理论   175篇
环境理论   3篇
污染及防治   118篇
评价与监测   74篇
社会与环境   91篇
灾害及防治   121篇
  2024年   5篇
  2023年   21篇
  2022年   19篇
  2021年   36篇
  2020年   48篇
  2019年   50篇
  2018年   41篇
  2017年   74篇
  2016年   83篇
  2015年   75篇
  2014年   94篇
  2013年   143篇
  2012年   114篇
  2011年   126篇
  2010年   105篇
  2009年   92篇
  2008年   76篇
  2007年   121篇
  2006年   126篇
  2005年   105篇
  2004年   85篇
  2003年   99篇
  2002年   66篇
  2001年   60篇
  2000年   61篇
  1999年   47篇
  1998年   29篇
  1997年   18篇
  1996年   15篇
  1995年   14篇
  1994年   11篇
  1993年   9篇
  1992年   6篇
  1991年   6篇
  1990年   8篇
  1989年   5篇
  1988年   8篇
  1987年   3篇
  1986年   3篇
  1985年   3篇
  1984年   7篇
  1983年   3篇
  1982年   5篇
  1980年   4篇
  1978年   5篇
  1977年   2篇
  1976年   3篇
  1974年   2篇
  1972年   4篇
  1971年   4篇
排序方式: 共有2153条查询结果,搜索用时 140 毫秒
211.
应急照明是现代建筑安全保障的重要设施之一,它同人身安全和建筑物安全紧密相关。根据建筑电气设计规范对应急照明的具体规定,对应急照明的设计要求做了进一步探讨和归纳总结,并结合具体问题对应急照明设置场所、供电时间、电源供电方式、控制方式、施工设计及设计要点等方面进行了阐述,对应急照明的设计和实践应用中出现的问题进行了分析,并提出了整改措施。  相似文献   
212.
近年来,国内举办的各类博览会内容繁多,如车展、服装展、机电展、大型机械、油煤化工、农产品、园林技术以及各类综合性展览,展会消防安全工作尤为重要.布展期间的消防设计审核作为展会消防工作的源头,是消防监督人员及展会相关工作人员应当提前介入、重点把关的首要问题.笔者根据各地参加展会工作实践经验,针对大型展会布展中的特装展位消防设计审核工作进行探讨,包括布展前期告知事项、特装展位设计审核及特装布展施工监督管理等方面的具体要求,从源头保证大型博览会的消防安全.  相似文献   
213.
国家矿井安全生产监管物联网应用示范工程总体设计研究   总被引:1,自引:0,他引:1  
国家矿井安全生产监管物联网应用示范工程是由国家发展和改革委员会支持、国家安全生产监督管理总局牵头组织,以神华集团有限责任公司、中国中煤能源集团有限公司为具体试点单位的国家级示范工程建设项目,旨在利用物联网技术提高煤矿安全生产预测预警和事故风险防控水平,促进物联网技术在煤矿安全生产领域的推广应用和产业发展,是坚持科学发展安全发展、落实科技兴安战略的重要举措。本文探讨了国家矿井安全生产监管物联网应用示范工程建设的必要性和意义,主要介绍了示范工程建设目标、总体实施方案、总体技术方案和实施技术路线等。  相似文献   
214.
The impact of large-scale urban development on land resources has long been debated by urban planners and designers. This study investigated the extent to which different urban characteristics are associated with land-cover change. The Yangtze River Delta region in China, forming one of the largest sprawling urban landscapes among the regions around the world, was chosen for the study area. Spatial analysis and multiple regression methods were applied to empirically investigate the pattern of resource sites lost to urban development in the area between the 1950s and 2017. The results showed that contrary to the widespread notion that large-sized cities are predominantly responsible for a region’s environmental degradation, city size was not a significant factor in determining the rate of resource loss. Large-sized cities gained their populations with far lesser impacts on land than small-sized cities and towns if normalized to the same number of populations. One explanation for the diminishing effect of city size on land-cover change relates to the degree of spatial dispersion of urban development and local differences in social valuation of diversified lands by cities.  相似文献   
215.
We experimentally test the truth-telling mechanism proposed by Montero (2008) for eliciting firms' abatement costs. We compare this mechanism with two well-known alternative allocation mechanisms, free and costly allocation of permits at the Pigouvian price. Controlling for the number of firms and the firms' maximal emissions, we find that, in line with the theoretical predictions, firms over-report their maximal emissions under free allocation of permits and under-report these under costly allocation of permits. Under Montero's mechanism, by contrast, firms almost always report their maximal emissions truthfully. However, in terms of efficiency, the difference between Montero's mechanism and costly allocation disappears with industries including more than one firm.  相似文献   
216.
While water-energy-food (WEF) Nexus is one of the most important, and widely investigated, environmental topics of our time, previous stock taking efforts possess notable limitations, namely (i) their focus is restricted to research articles, and (ii) there is less focus on nexus permutations that begin with energy and food. This paper assembled more than 900 documents and systematically categorized them according to more than 10 key parameters (e.g. scale, methods, limitations), to characterize approaches, achieved outcomes and presence of variables likely to support on-the-ground change. Our results reveal that WEF Nexus activities are often driven by the water sector, undertaken at global and national scale and authored by experts from diverse backgrounds. Among the utilized methods, modelling and review (i.e. systematic) are the most common. While climate change and governance are routinely considered in WEF Nexus documents, gender, stakeholders and capacity are not. These findings highlight areas for improvement in the design of WEF Nexus initiatives.  相似文献   
217.
Among the many occupational risks construction workers encounter every day falling from a height is the most dangerous. The objective of this article is to propose a simple analytical design method for horizontal lifelines (HLLs) that considers anchorage flexibility. The article presents a short review of the standards and regulations/acts/codes concerning HLLs in Canada the USA and Europe. A static analytical approach is proposed considering anchorage flexibility. The analytical results are compared with a series of 42 dynamic fall tests and a SAP2000 numerical model. The experimental results show that the analytical method is a little conservative and overestimates the line tension in most cases with a maximum of 17%. The static SAP2000 results show a maximum 2.1% difference with the analytical method. The analytical method is accurate enough to safely design HLLs and quick design abaci are provided to allow the engineer to make quick on-site verification if needed.  相似文献   
218.
219.
The promise of environmental conservation incentive programs that provide direct payments in exchange for conservation outcomes is that they enhance the value of engaging in stewardship behaviors. An insidious but important concern is that a narrow focus on optimizing payment levels can ultimately suppress program participation and subvert participants’ internal motivation to engage in long-term conservation behaviors. Increasing participation and engendering stewardship can be achieved by recognizing that participation is not simply a function of the payment; it is a function of the overall structure and administration of the program. Key to creating innovative and more sustainable programs is fitting them within the existing needs and values of target participants. By focusing on empathy for participants, co-designing program approaches, and learning from the rapid prototyping of program concepts, a human-centered approach to conservation incentive program design enhances the propensity for discovery of novel and innovative solutions to pressing conservation issues.  相似文献   
220.
隐伏盲空区是严重威胁露天矿山正常采矿作业的安全隐患,应予以探明并处置。针对露天矿隐伏盲空区探测难度大、崩落处置爆破设计精度差等问题,以白马铁矿1号溜井盲空区为例,首先基于矿山历史资料,利用钻探手段,初步圈定盲空区异常分布范围;然后运用钻孔激光扫描设备进行三维精确扫描,获得盲空区塌腔三维形态和真实边界,并以实测数据为基础,利用逆向建模方法,构建盲空区三维可视化模型;最后根据盲空区的三维空间特征和分布条件,进行爆破分区及参数优化设计。结果表明:采用钻探圈定结合三维激光精确扫描建模的综合探测方法,可获得露天矿山盲空区的可靠信息,准确掌握盲空区垮塌现状,进而为制定更为精准的爆破设计方案提供重要依据,最终达到消除盲空区的目的。研究结果对保障矿山安全生产具有重要意义,同时可为类似工程提供有益参考。  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