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881.
We address the future of science and governance for the California Delta, focusing on the CALFED Bay-Delta Program, an interagency, multi-stakeholder effort to understand and manage the Delta for multiple purposes. We portray a Delta history as a coevolutionary process between science, governance and ecosystems. Global integrated environmental assessments (IEA) provide insights into understanding complex, dynamic socio-ecological systems. Many of the discursive stakeholder and scientific activities that have arisen under CALFED are similar to IEA and remain essential to the shared learning needed to effectively interact with a dynamic Delta. More deliberately enmeshing environmental monitoring, analysis, and collective learning into Delta governance will improve outcomes.  相似文献   
882.
French and European incentives, such as Plan Ecophyto 2018, European directive for a sustainable use of pesticides, reinforce the requirement for vine-growers to engage in more environmentally friendly farming practices. In this respect, this paper presenting the results of a large questionnaire survey conducted in Bordeaux area vineyards and focusing on the behaviour of their vine-growers towards environmental innovations is particularly adequate. Founding that the most important environmental issue in vineyards relates to the use of pesticides, the paper characterizes the main economic and cognitive factors determining vine-growers' environmental innovations. It allows determining possible policies milestones, efficient and feasible, towards a more environmentally friendly vineyard. The paper first outlines the analytical framework, then highlights the main results and, finally, goes through further discussion and policy implications.  相似文献   
883.
环境污染突发事件的发生,影响广、危害大,迫切需要发生地的环境监测部门迅速反应,进行快速监测,迅速报出监测结果,为污染物的控制提供科学依据。因此对环境应急监测的管理就显得非常重要,不仅要对技术人员进行培训,还要准备仪器设备;不仅要准备应急监测预案,还要准备查询、应用工具,包括查询应用软件,只有进行充分的环境应急监测管理,才能有效地进行环境应急监测响应,才能为污染物应急控制决策、为保护环境质量、保护人民的生命财产安全作出贡献。  相似文献   
884.
Introduction: The phenomenon that construction workers do not use personal protective equipment (PPE) is a major reason for the high occurrence frequency of accidents in the construction industry. However, little efforts have been made to quantitatively examine the factors influencing construction workers’ acceptance of PPE. Method: In the current study, a PPE acceptance model for construction workers (PAMCW) was proposed to address the noted need. The PAMCW incorporates the technology acceptance model, theory of planned behavior, risk perception, and safety climate for explaining construction worker acceptance of PPE. 413 construction workers participated in this study to fill out a structured questionnaire. The PAMCW was analyzed using structural equation modeling. Results: Results provide evidence of the applicability of the technology acceptance model and theory of planned behavior to the PPE acceptance among construction workers. The positive influence of safety climate and risk perception-severity on attitude toward using PPE was significant. Safety climate positively influences perceived usefulness. Risk perception-worry and unsafe was found to positively affect intention to use PPE. Practical Applications: Practical suggestions for increasing construction workers’ use of PPE are also discussed.  相似文献   
885.
Petrochemical plants are continuously turning into large-size corporations, the installations of facilities show a developing trend from ground to underground because of the difference in land using rate. In this regard, the safety distance of petrochemical equipment buried in both ground and underground cases were investigated based on risk assessment. As a case study, gasoline tank and LPG tank set on the ground and underground are singled out to compare the risks involved. The research showed that the setting case of installation had a great influence on safety distance. Two cases have 80% reduction of equivalent safety distance compared with the rest of the cases. It was found that when the gasoline storage tank was placed underground alone, the PLL value decreased by 36.7%. Only LPG tank was placed underground, and the PLL decreased by 6.33%, and the gasoline and LPG storage tanks were placed underground simultaneously, the PLL value declined by 42.3%. Thus, the layout of plants could be further optimized, which can greatly improve the performances of land use efficiency and safety. In addition, this paper, the selection of embedding methods and the sensitivity of underground case to overpressure was resumed from two aspects: soil properties and burial depth. For the soil properties, it was found that the water saturated sandy soil with high air content and the low density unsaturated sandy soil had better effects on weakening overpressure. Such properties are particularly beneficial to reducing the occurrence rate of accidents. In terms of burial depth, it can be observed that as the burial depth was changed from 0.5m to 1.1m, the value of overpressure has dropped dramatically. When the burial depth was 2m, the damage to personnel and buildings has been greatly reduced beyond 2m from the explosion center.  相似文献   
886.
Risk management can be defined as coordinated activities to conduct and control an organization with consideration of risk. Recently, risk management strategies have been developed to change the approach to hazards and risks. Resilience as a safety management theory considers the technical and social aspects of systems simultaneously. Resilience in process industries, as a socio-technical system, has four aspects of early detection, error-tolerant design, flexibility, and recoverability. Meanwhile, process industries' resilience has three phases: avoidance, survival, and recovery, determining the transition between normal state, process upset event, and catastrophic event. There may be various technical and social failures such as regulatory and human or organizational items that can lead to upset or catastrophic events. In the avoidance phase, the upset event is predicted, and thus, the system remains in a normal state. For the survival phase, the system state is assumed to be an upset process event, and the system tries to survive through the unhealthy process conditions or remains in the same state, probably with low performance. In the recovery phase, the system is supposed to be catastrophic, and the emergency barriers are prioritized to show the severity of the consequences and response time, leading to a resumption of a normal state. Therefore, a resilience-based network can be designed for process industries to show its inherent dynamic transition in nature. In this study, network data envelopment analysis (DEA), as a mathematical model, is used to evaluate the relative efficiency of the process industries regarding a network transition approach based on the system's internal structure. First, a resilience-based network is designed to consist of three states of normal, upset, and catastrophic events. Then, the efficiency of each industrial department, which is defined as decision-making units (DMUs), is evaluated using network DEA. As a case study, a refinery that is considered a critical process industry is assessed. Using the proposed model shows the efficient and inefficient DMUs in each of three states of normal, upset, and catastrophic events of the process and the projection onto efficient frontiers. Besides calculating the network efficiency, the performance of each state is extracted to precisely differentiate between DMUs. The results of this study, which is one of the fewest cases in the area of performance evaluation of process industries with a network approach, indicated a robust viewpoint for monitoring and assessment of risks.  相似文献   
887.
The liquid fuel safety issues on fuel storage, transportation and processing have gained most attention because of the high fire risk. In this paper, some 0# diesel pool fire experiments with different diameters (0.2–1 m) were conducted with initial fuel thicknesses of 2 cm and 4 cm, respectively, to obtain liquid fuel combustion characteristics. Some key parameters including mass burning rate, flame height and the flame radiative heat flux, associated with fire risk, were investigated and determined. Subsequently, a detail quantitative risk assessment framework for 0# diesel pool fire is proposed based on the 0# diesel burning characteristics. In the framework, the probability of personal dead and the facility failure are calculated by the vulnerability models, respectively. In the end, 10 special tank fire scenarios were selected to show the whole risk calculation process. The tank diameter and the distance to pool fires were paid more attention in the cases. The safety distances in the cases are provided for the persons and nearby facilities, respectively. The paper enriches the basic experimental data and the provided framework is useful to the management of 0# diesel tank areas.  相似文献   
888.
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   
889.
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   
890.
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   
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