全文获取类型
收费全文 | 262篇 |
免费 | 28篇 |
国内免费 | 8篇 |
专业分类
安全科学 | 109篇 |
废物处理 | 1篇 |
环保管理 | 39篇 |
综合类 | 109篇 |
基础理论 | 8篇 |
污染及防治 | 2篇 |
评价与监测 | 16篇 |
社会与环境 | 6篇 |
灾害及防治 | 8篇 |
出版年
2024年 | 1篇 |
2023年 | 7篇 |
2022年 | 3篇 |
2021年 | 12篇 |
2020年 | 16篇 |
2019年 | 12篇 |
2017年 | 10篇 |
2016年 | 15篇 |
2015年 | 13篇 |
2014年 | 19篇 |
2013年 | 11篇 |
2012年 | 30篇 |
2011年 | 28篇 |
2010年 | 17篇 |
2009年 | 23篇 |
2008年 | 6篇 |
2007年 | 15篇 |
2006年 | 9篇 |
2005年 | 10篇 |
2004年 | 6篇 |
2003年 | 6篇 |
2002年 | 9篇 |
2001年 | 8篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1985年 | 1篇 |
排序方式: 共有298条查询结果,搜索用时 15 毫秒
241.
Understanding the commonalities among previous chemical process incidents can help mitigate recurring incidents in the chemical process industry and will be useful background knowledge for designers intending to foster inherent safety. The U.S. Chemical Safety and Hazard Investigation Board (CSB) reports provide detailed and vital incident information that can be used to identify possible commonalities. This study aims to develop a systematic approach for extracting data from the CSB reports with the objective of establishing these commonalities. Data were extracted based on three categories: attributed incident causes, scenarios, and consequences. Seventeen causal factors were classified as chemical indicators or process indicators. Twelve chemical indicators are associated with the hazards of the chemicals involved in the incidents, whereas five process indicators account for the hazards presented by process conditions at the time of the incident. Seven scenario factors represent incident sequences, equipment types, operating modes, process units, domino effects, detonation likelihood for explosion incidents, and population densities. Finally, three consequence factors were selected based on types of chemical incidents, casualties, population densities, and economic losses. Data from 87 CSB reports covering 94 incidents were extracted and analyzed according to the proposed approach. Based on these findings, the study proposes guidelines for future collection of information to provide valuable resources for prediction and risk reduction of future incidents. 相似文献
242.
基于能量意外释放论,提出改进的JHA风险辨识方法。在按设备结构划分维修作业后,不划分作业步骤,而是根据风险来源进行辨识,实现了辨识的实用性和系统全面性。基于辨识结果,建立信息化维修作业风险信息数据库,并作为《检修项目指令书》安全措施的信息支撑。实践表明,改进的JHA辨识方法是有效的,信息化应用改变了经验式的《检修项目指令书》,提高了风险管控的有效性。 相似文献
243.
244.
为保障海底油气管道维修作业安全,提出1种基于JSA-BN的作业风险分析方法。采用JSA方法辨识分析水上提管维修作业过程中潜在的风险因素,得出不同作业步骤的风险等级;建立水上提管维修作业贝叶斯网络模型,计算出各作业环节的成功概率;依托贝叶斯网络的逆向推理及敏感性分析能力,实现水上提管维修作业风险薄弱点的定量预测和评估。研究结果表明:提出的基于JSA-BN的作业风险分析方法可应用于近岸海底管道应急维修作业风险分析;在整个水上提管维修作业活动中,提管作业和切割破损管道作业为关键作业环节,提升过程中碰撞、掉落事件为薄弱风险因素。 相似文献
245.
Xinxian Zhang A. David McGuire Roger W. Ruess 《Mitigation and Adaptation Strategies for Global Change》2006,11(1):147-171
A major challenge confronting the scientific community is to understand both patterns of and controls over spatial and temporal
variability of carbon exchange between boreal forest ecosystems and the atmosphere. An understanding of the sources of variability
of carbon processes at fine scales and how these contribute to uncertainties in estimating carbon fluxes is relevant to representing
these processes at coarse scales. To explore some of the challenges and uncertainties in estimating carbon fluxes at fine
to coarse scales, we conducted a modeling analysis of canopy foliar maintenance respiration for black spruce ecosystems of
Alaska by scaling empirical hourly models of foliar maintenance respiration (Rm) to estimate canopy foliar Rm for individual stands. We used variation in foliar N concentration among stands to develop hourly stand-specific models and
then developed an hourly pooled model. An uncertainty analysis identified that the most important parameter affecting estimates
of canopy foliar Rm was one that describes Rm at 0 ∘C per g N, which explained more than 55% of variance in annual estimates of canopy foliar Rm. The comparison of simulated annual canopy foliar Rm identified significant differences between stand-specific and pooled models for each stand. This result indicates that control
over foliar N concentration should be considered in models that estimate canopy foliar Rm of black spruce stands across the landscape. In this study, we also temporally scaled the hourly stand-level models to estimate
canopy foliar Rm of black spruce stands using mean monthly temperature data. Comparisons of monthly Rm between the hourly and monthly versions of the models indicated that there was very little difference between the estimates
of hourly and monthly models, suggesting that hourly models can be aggregated to use monthly input data with little loss of
precision. We conclude that uncertainties in the use of a coarse-scale model for estimating canopy foliar Rm at regional scales depend on uncertainties in representing needle-level respiration and on uncertainties in representing
the spatial variability of canopy foliar N across a region. The development of spatial data sets of canopy foliar N represents
a major challenge in estimating canopy foliar maintenance respiration at regional scales. 相似文献
246.
漏电保护开关是一种防止触电事故的辅助装置,目前在地勘单位使用较广。如何保证和提高它的可靠性,迅速诊断故障,维护系统正常运行,本文就这一问题进行探讨,并给出实际运行中的常见故障及其对策。 相似文献
247.
248.
土工合成材料在三峡库区重庆市万州区库岸防护中的应用可行性研究 总被引:2,自引:0,他引:2
三峡水库建成后,库水位的消涨变化非常频繁且变化幅度比水库建造前有了明显提高.这势必会对库岸的稳定性产生影响,引起库岸堆积体沿深层基岩面滑动或发生塌岸,必须采取工程措施进行防治.而土工合成材料以其良好的整体性、抗变形能力、保土透水性能及施工简便、造价低等独特优势和兼具反滤、排水、防渗、隔离、防护、加筋等强大功能不失为一种上好的库岸防护材料.本文首先介绍了土工合成材料的种类及其功能,进而简单介绍了土工合成材料在库岸防护工程中的应用现状;然后在详细分析了重庆市万州区鞍子坝库岸段工程地质条件的基础上计算了堆积体沿基岩面滑动的稳定性,并分析了库岸的破坏形式;最后对库岸防护采用加筋土进行了初步设计并对设计从外部稳定性(地基承载力、抗滑稳定性、抗倾覆稳定性)和内部稳定性(土工格栅强度和抗拔稳定性)进行了验算.研究结果认为利用土工合成材料对库岸防护完全可行。 相似文献
249.
本文介绍了有关计算机病毒的一些基本知识,并根据长期的工作实践,提出了在计算机集中使用的公共场合病毒防治办法,以保证计算机的正常运行。 相似文献
250.
This research examined community acceptance of policy instruments that could be used to promote ongoing maintenance of domestic rainwater tank systems. Using an online survey of 533 tank owners in South East Queensland, Australia, the research investigated four sets of factors that influence policy acceptance: features of the policy, judgements of policy fairness and effectiveness, contextual framing, and individual attitudes and motivations towards tank maintenance. An experimental design incorporating choice modelling was employed. Results demonstrated that perceptions of policy fairness and effectiveness are important to acceptance. Policies that include enabling features associate with increased perceptions of effectiveness, and policies that use incentives are linked to increased perceptions of both fairness and effectiveness. Individual attitudes and motivations regarding tank maintenance were significant predictors of policy support. Perceptions of a person's own ability to undertake tank maintenance tasks were negative predictors of policy intervention, suggesting that people who believe they can carry out maintenance themselves may not see the need for a policy that encourages tank maintenance to exist. The findings are discussed in relation to issues of policy design. 相似文献