全文获取类型
收费全文 | 5705篇 |
免费 | 150篇 |
国内免费 | 146篇 |
专业分类
安全科学 | 603篇 |
废物处理 | 54篇 |
环保管理 | 1274篇 |
综合类 | 2194篇 |
基础理论 | 392篇 |
环境理论 | 19篇 |
污染及防治 | 426篇 |
评价与监测 | 713篇 |
社会与环境 | 230篇 |
灾害及防治 | 96篇 |
出版年
2023年 | 43篇 |
2022年 | 51篇 |
2021年 | 98篇 |
2020年 | 213篇 |
2019年 | 86篇 |
2018年 | 70篇 |
2017年 | 139篇 |
2016年 | 183篇 |
2015年 | 154篇 |
2014年 | 231篇 |
2013年 | 299篇 |
2012年 | 199篇 |
2011年 | 417篇 |
2010年 | 192篇 |
2009年 | 366篇 |
2008年 | 299篇 |
2007年 | 285篇 |
2006年 | 257篇 |
2005年 | 171篇 |
2004年 | 179篇 |
2003年 | 236篇 |
2002年 | 208篇 |
2001年 | 197篇 |
2000年 | 228篇 |
1999年 | 205篇 |
1998年 | 169篇 |
1997年 | 172篇 |
1996年 | 109篇 |
1995年 | 81篇 |
1994年 | 98篇 |
1993年 | 100篇 |
1992年 | 65篇 |
1991年 | 34篇 |
1990年 | 20篇 |
1989年 | 22篇 |
1988年 | 12篇 |
1987年 | 13篇 |
1986年 | 19篇 |
1985年 | 17篇 |
1984年 | 16篇 |
1983年 | 6篇 |
1982年 | 7篇 |
1981年 | 12篇 |
1980年 | 5篇 |
1979年 | 1篇 |
1978年 | 11篇 |
1977年 | 5篇 |
1974年 | 1篇 |
排序方式: 共有6001条查询结果,搜索用时 156 毫秒
911.
近年来,天然气消费量迅速增长,天然气领域的投入和天然气储量、产量和贸易量也呈迅速增长态势,并显示出增长的巨大潜力。天然气市场需求量的大幅度增加与国内天然气供给不足造成的供需不平衡,给天然气供气业务带来了极大的挑战。本文根据近两年来天然气供应面临的危机,分别对天然气供气产业链的上、中、下游的突发事件风险进行分析;并针对供气业务中断带来的风险,从突发事件分级、应急处置流程等两个关键要素着手对应急预案进行优化。该研究对完善天然气供气突发事件应急预案、有效快速应对突发事件提供了参考和指导。 相似文献
912.
Layer of protection analysis (LOPA) is a widely used semi-quantitative risk assessment method. It provides a simplified and less precise method to assess the effectiveness of protection layers and the residual risk of an incident scenario. The outcome failure frequency and consequence of that residual risk are intended to be conservative by prudently selecting input data, given that design specification and component manufacturer's data are often overly optimistic. There are many influencing factors, including design deficiencies, lack of layer independence, availability, human factors, wear by testing and maintenance shortcomings, which are not quantified and are dependent on type of process and location. This makes the risk in LOPA usually overestimated. Therefore, to make decisions for a cost-effective system, different sources and types of uncertainty in the LOPA model need to be identified and quantified. In this study, a fuzzy logic and probabilistic hybrid approach was developed to determine the mean and to quantify the uncertainty of frequency of an initiating event and the probabilities of failure on demand (PFD) of independent protection layers (IPLs). It is based on the available data and expert judgment. The method was applied to a distillation system with a capacity to distill 40 tons of flammable n-hexane. The outcome risk of the new method has been proven to be more precise compared to results from the conventional LOPA approach. 相似文献
913.
This paper focuses on the analysis of the possibility of domino effect in underground parallel pipelines relying on historical accident data and pipeline crater models. An underground pipeline can be considered as safe following an accident with an adjacent gas or liquefied pipeline when it remains outside the ground crater generated. In order to prevent the domino effect in these cases, the design of parallel pipelines has to consider adequate pipeline separations based on the crater width, which is one of the widely used methods in engineering applications. The objective of this work is the analysis of underground petroleum product pipelines ruptures with the formation of a ground crater as well as the evaluation of possible domino effects in these cases. A detailed literature survey has been carried out to review existing crater models along with a historical analysis of past accidents. A FORTRAN code has been implemented to assess the performance of the Gasunie, the Batelle and the Advantica crater models. In addition to this, a novel Accident-Based crater model has been presented, which allows the prediction of the crater width as a function of the relevant design pipeline parameters as well as the soil density. Modifications have also been made to the Batelle and Accident-Based models in order to overcome the underestimation of the crater width. The calculated crater widths have been compared with real accident data and the performance evaluation showed that the proposed Accident-Based model has a better performance compared to other models studied in this work. The analysis of forty-eight past accidents indicated a major potential of underground parallel pipelines domino effect which is proven by two real cases taken from the literature. Relying on the investigated accidents, the crater width was smaller than or equal to 20 m in most cases indicating that the definition of underground pipeline separations at around 10 m would be sufficient to ensure a small probability of the domino effect. 相似文献
914.
The objective of this article is to present a method for developing collision risk indicators applicable for autonomous remotely operated vehicles (AROVs), which are essential for promoting situation awareness in decisions support systems. Three suitable risk based collision indicators are suggested for AROVs namely, time to collision, mean time to collision and mean impact energy. The proposed indicators are classified into different thresholds; low, intermediate and high. An AROV flight path is simulated to gather input data to calculate the proposed indicators and three collision targets are established, i.e., subsea structure, seabed and a cooperating AROV. The proposed indicator development method together with the case study show a proof-of-concept that the combination of mean time to collision and mean impact energy indicators can identify risk prone waypoints in the AROV path. The method results in an overall risk picture for a given AROV path. The results may provide useful input in replanning of mission paths and for implementation of risk reducing measures. Even though the method focuses on collision risk, it can be used for other accident scenarios for AROVs. 相似文献
915.
This paper presents an argument that improvement in operational safety can be achieved concurrently with increased operational efficiency. This is a fundamentally different viewpoint on the investment in safety. Traditionally, the cost of providing safety barriers is offset by the expected benefits of reducing the occurrence and severity of accidents. Our approach departs from this method of accounting for safety improvements and focuses on planning as a means of managing systems' response uncertainty and consequently reducing both major accident risk and the cost of operations. The scope of the paper is limited to interventions such as maintenance and repairs and defined in the context of major accident prevention e.g. hydrocarbon leaks. However, the developed methodology is general enough to be applied across the spectrum of process industry facilities and operations. 相似文献
916.
917.
918.
919.
《环境质量管理》2018,27(4):125-133
Environmental management systems (EMS) have been introduced globally to reduce environmental degradation issues brought about by industrial development. The research discussed in this paper is aimed at identifying the benefits and motivations of the implementation of EMS in compliance with the International Organization for Standardization (ISO) 14001 standard in Malaysian industries by using the pairwise comparison method. Experts in EMS from the Scientific and Industrial Research Institute of Malaysia were invited to participate in the research panel. Based on the experts’ input, data analysis was carried out by using multi‐criteria pairwise comparisons. The findings showed the ranked benefits and motivations of the implementation of the ISO 14001 standard for businesses. The results can indicate to policy‐makers and business advisors how businesses can be encouraged to implement the ISO 14001. 相似文献
920.
Chloe Begg 《Local Environment》2018,23(4):383-397
Over the past few decades, there has been an increasing interest in the active involvement of local stakeholders in the management of floods in Europe. Such involvement is seen as necessary as the management of floods becomes more complex. Management approaches now seek to include a range of potential measures to reduce risk (e.g. structural defence, spatial planning and property-level protection measures). Local stakeholder involvement is seen to be important because governments lack the capacities such as knowledge and funding required to deliver all these measures alone. This paper focuses on the implications that more participative approaches have on the fairness of European flood risk management (FRM). Studies of environmental justice are well placed to address this question because they are interested in who is included and excluded from decisions related to the distribution of environmental goods (resources) and bads (risks). Existing literature suggests that fair decision-making processes (procedural justice) can lead to fair distribution or resources and risks (distributive justice). This literature review of 30 peer-reviewed papers provides an analysis of justice and FRM by assessing practices of participation which are presented in the recent literature on local stakeholder involvement in FRM in England, Germany and the Netherlands. It was found that participation in practice generally focuses on transferring responsibility to the local level at the expense of power. This paper discusses the implications that this finding has for justice and synthesises potential ways forward based on recommendations of the reviewed literature. 相似文献