全文获取类型
收费全文 | 1968篇 |
免费 | 198篇 |
国内免费 | 60篇 |
专业分类
安全科学 | 1438篇 |
废物处理 | 8篇 |
环保管理 | 79篇 |
综合类 | 314篇 |
基础理论 | 105篇 |
污染及防治 | 21篇 |
评价与监测 | 13篇 |
社会与环境 | 11篇 |
灾害及防治 | 237篇 |
出版年
2024年 | 1篇 |
2023年 | 33篇 |
2022年 | 64篇 |
2021年 | 79篇 |
2020年 | 98篇 |
2019年 | 78篇 |
2018年 | 40篇 |
2017年 | 71篇 |
2016年 | 56篇 |
2015年 | 77篇 |
2014年 | 70篇 |
2013年 | 80篇 |
2012年 | 179篇 |
2011年 | 150篇 |
2010年 | 107篇 |
2009年 | 117篇 |
2008年 | 66篇 |
2007年 | 152篇 |
2006年 | 169篇 |
2005年 | 106篇 |
2004年 | 104篇 |
2003年 | 73篇 |
2002年 | 50篇 |
2001年 | 60篇 |
2000年 | 25篇 |
1999年 | 27篇 |
1998年 | 26篇 |
1997年 | 16篇 |
1996年 | 15篇 |
1995年 | 1篇 |
1994年 | 7篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1978年 | 3篇 |
1977年 | 1篇 |
排序方式: 共有2226条查询结果,搜索用时 15 毫秒
81.
火灾频发暴露我国城市公共安全系统脆弱性 总被引:1,自引:2,他引:1
刘铁民 《中国安全生产科学技术》2011,7(3):5-9
为剖析近来我国火灾事故频发的原因,以上海"11·15"火灾事故为典型案例,分析了事件灾害过程和行为特征。结果提示:事件过程所暴露的风险管理疏失;安全基础设施薄弱;应急准备欠缺和应急响应能力不足等现象,凸显我国城市公共安全领域的系统脆弱性。系统脆弱性可能是导致"11·15"火灾事故发生与成灾的主要原因,作者认为系统脆弱性存在实质是公共安全体系的结构性缺陷。建议应从制度化建设入手,注意克服系统脆弱性,以加强公共安全保障能力,提高社会管理水平。 相似文献
82.
We study a dynamic common pool resource game in which current resource stock depends on resource extraction in the previous period. Our model shows that for a sufficiently high regrowth rate, there is no commons dilemma: the resource will be preserved indefinitely in equilibrium. Lower growth rates lead to depletion. Laboratory tests of the model indicate that favorable ecological characteristics are necessary but insufficient to encourage effective CPR governance. Before the game, we elicit individual willingness to follow a costly rule. Only the presence of enough rule-followers preserves the resource given favorable ecological conditions. 相似文献
83.
JOHAN A. OLDEKOP ANTHONY J. BEBBINGTON DAN BROCKINGTON RICHARD F. PREZIOSI 《Conservation biology》2010,24(2):461-469
Abstract: The lack of concrete instances in which conservation and development have been successfully merged has strengthened arguments for strict exclusionist conservation policies. Research has focused more on social cooperation and conflict of different management regimes and less on how these factors actually affect the natural environments they seek to conserve. Consequently, it is still unknown which strategies yield better conservation outcomes? We conducted a meta‐analysis of 116 published case studies on common resource management regimes from Africa, south and central America, and southern and Southeast Asia. Using ranked sociodemographic, political, and ecological data, we analyzed the effect of land tenure, population size, social heterogeneity, as well as internally devised resource‐management rules and regulations (institutions) on conservation outcome. Although land tenure, population size, and social heterogeneity did not significantly affect conservation outcome, institutions were positively associated with better conservation outcomes. There was also a significant interaction effect between population size and institutions, which implies complex relationships between population size and conservation outcome. Our results suggest that communities managing a common resource can play a significant role in conservation and that institutions lead to management regimes with lower environmental impacts. 相似文献
84.
Patch Mosaic Burning for Biodiversity Conservation: a Critique of the Pyrodiversity Paradigm 总被引:4,自引:0,他引:4
Abstract: Fire management is increasingly focusing on introducing heterogeneity in burning patterns under the assumption that "pyrodiversity begets biodiversity." This concept has been formalized as patch mosaic burning (PMB), in which fire is manipulated to create a mosaic of patches representative of a range of fire histories to generate heterogeneity across space and time. Although PMB is an intuitively appealing concept, it has received little critical analysis. Thus we examined ecosystems where PMB has received the most attention and has been the most extensively implemented: tropical and subtropical savannas of Australia and Africa. We identified serious shortcomings of PMB: the ecological significance of different burning patterns remains unknown and details of desired fire mosaics remain unspecified. This has led to fire-management plans based on pyrodiversity rhetoric that lacks substance in terms of operational guidelines and capacity for meaningful evaluation. We also suggest that not all fire patterns are ecologically meaningful: this seems particularly true for the highly fire-prone savannas of Australia and South Africa. We argue that biodiversity-needs-pyrodiversity advocacy needs to be replaced with a more critical consideration of the levels of pyrodiversity needed for biodiversity and greater attention to operational guidelines for its implementation. 相似文献
85.
87.
哈龙固定灭火系统替代技术 总被引:3,自引:0,他引:3
介绍了哈龙固定灭火系统淘汰背景,哈龙灭火系统替代技术发展现状。结合消除建审工作经验,阐述了作为哈龙替代系统且目前在国内工程实践中应用的CO2灭火系统、INERGEN灭火系统、FM-200灭火系统及EBM灭火系统主要性能及与哈龙系统的差异,探讨哈龙替代系统技术发展趋势,对气体灭火系统设计选型有一定参考价值。 相似文献
88.
火灾中双层窗玻璃破裂机理的研究 总被引:1,自引:0,他引:1
把单层窗玻璃破裂的模型作为研究基础,基于原有的单层窗玻璃破裂的计算软件开发设计了双层窗玻璃破裂的模型,并对双层玻璃的内表面及其空隙的热传递过程和连续发生的玻璃破裂机理进行了研究。 相似文献
89.
90.