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991.
This contribution characterises the sources and distribution of polycyclic aromatic hydrocarbons (PAHs) in sediments of the Basque coast (Bay of Biscay). Different source characterisation approaches (i.e. GIS assisted-chemometrics, PAH diagnostic ratios and analyses of composition profiles) were used in combination to successfully identify the factors determining the origin and distribution of PAHs. Urban/industrial combustion processes were identified as the main PAH source. However, the analysis of PAH composition patterns and diagnostic ratios identified secondary natural and petrogenic PAH sources on small spatial scales. The median ∑18PAH concentration ranged from 66 μg kg?1 (d.w.) to 7021 μg kg?1 (d.w.). The Ibaizabal estuary, which supports most of the anthropogenic pressure in the region (i.e. urban development, industrialisation, commercial and recreational harbours), also showed the highest PAH concentrations. On the shelf, human activities, hydrodynamic conditions and geomorphological features led to spatial differences in the PAH concentrations among sectors: the offshore and west sectors were characterised by higher concentrations, while the lowest values were found in the mid and east sectors. The results enhance the knowledge on PAH-related contamination processes and could be used to support the environmental assessment process required under current European marine legislation.  相似文献   
992.
Information and communications technology (ICT), primarily mobile telephones and social media, is increasingly important in crisis and disaster response in developing countries. This fact raises an important question: in an information environment that includes traditional media such as radio and television, who are the people that trust information from ICT enough to act on it during a disaster? Drawing on a case study of and original survey data from the island nation of the Independent State of Samoa, this paper yields insights into who uses new technologies, particularly mobile telephones, to make decisions at the local level during crises such as natural disasters, as well as the socio‐political factors that motivate their behaviour. The results add to the growing pool of knowledge on utilisation of ICT and new technologies in developing countries for disaster response, and provide practical information on the social and political factors that lead people to trust different information sources and media.  相似文献   
993.
以平遥古城为例,探究游客信息行为对文化遗产旅游难忘体验的作用路径和异质性的调节效果。结果发现:游客信息行为对文化遗产旅游难忘体验的影响有直接影响和间接影响两条路径;异质性游客在信息对难忘体验的影响上存在显著调节效果;遗产地吸引力通过对游客再访意图的影响完全转化为难忘体验来发挥作用。  相似文献   
994.
水体富营养化驱动因子粗糙分析   总被引:3,自引:0,他引:3  
基于水质污染因子及其污染特性存在不确定性的特点,将粗糙集理论应用于水质污染因子及特性分析,建立污染因子评价粗糙集数学模型.该模型仅依赖于数据本身提供的信息,挖掘污染因子之间不确定的分类关系,计算其对水体污染或水质富营养化的重要性即贡献率大小,科学、快速和客观地揭示水体污染中起主导作用的污染来源,为水体污染控制提供理论依据.应用数学模型分析巢湖12个监测点的水质数据,确定巢湖主要污染因子及其导致湖泊富营养化的贡献率,结果显示TP、COD、TN等是导致巢湖水体富营养化的重要因子,今后应控制巢湖入湖水体的总磷及其有机污染物含量,以改善巢湖水质富营养化状况.  相似文献   
995.
Variations in geo-environmental attributes differ strongly from those of urban anthropogenic structures. Similarly, these types of structures are self-directed and arranged and prone to abrupt process-related changes and modifications. Thus, there are many reasons why planned urbanization forms in association with disturbances in ecosystem mobility. The current research highlights these variations in the context of social–cultural assessments within the Jhelum River watershed, which strongly expresses urbanization structure development mechanisms. The climate ranges from semi-arid to subhumid subtropical and sub-mountainous climate, though the extreme temperatures may rise as high as 49.4°C in June and may drop as low as ?1.6°C in January. The rainfall is low in the southwest and gradually increases towards the northeast, whereas the Salt Range is the major topographic feature that controls climatic impacts and promotes sustainable development. Cross-disciplinary methods are adopted in this investigation to assess the social–ecological landscape system (SELS) in terms of its mobility and degree of urbanization. The Sustainable Development Goals of the 2030 Agenda recognize that human livelihoods and the management of natural resources cannot be addressed separately. Investing in the sustainability of mountain communities and ecosystem conservation and protection will provide benefits for humanity as a whole. It pertains to the commensurate development of the SELS and its response to interruptions. Thus, a reliable SWOT analysis for management approaches is introduced that may enable the development of competencies that promote and lead towards rapid improvements in the sustainability of retrograde urban infrastructure, including watersheds.  相似文献   
996.
This paper proposes an ecological view to investigate how disparities in mobile technology use reflect vulnerabilities in communities vis‐à‐vis disaster preparedness. Data (n=1,603) were collected through a multi‐country survey conducted equally in rural and urban areas of Indonesia, Myanmar, Philippines, and Vietnam, where mobile technology has become a dominant and ubiquitous communication and information medium. The findings show that smartphone users' routinised use of mobile technology and their risk perception are significantly associated with disaster preparedness behaviour indirectly through disaster‐related information sharing. In addition to disaster‐specific social support, smartphone users' disaster‐related information repertoires are another strong influencing factor. In contrast, non‐smartphone users are likely to rely solely on receipt of disaster‐specific social support as the motivator of disaster preparedness. The results also reveal demographic and rural–urban differences in disaster information behaviour and preparedness. Given the increasing shift from basic mobile phone models to smartphones, the theoretical and policy‐oriented implications of digital disparities and vulnerability are discussed.  相似文献   
997.
大数据的发展及广泛应用加大了信息化系统及数据的脆弱性,信息安全风险向系统化、复杂化方向发展。在搜集、整理国内外相关研究成果基础上,系统辨识数据采集、数据传输、数据存储、数据分析4个大数据核心环节的信息安全风险,围绕“风险辨识、脆弱性降低、风险沟通、强化风险管理”的风险治理流程,以防范与化解信息安全风险为目标,提出大数据发展的信息安全防御策略。研究结果表明:大数据全生命周期是信息安全风险辨识的起点,强化大数据发展的信息安全风险防御,需要在风险辨识基础上,积极推进预防准备、风险沟通、信息安全事件处置及恢复总结。  相似文献   
998.
为了揭示复杂系统内安全信息传播的机理与故障模式和发展新的安全模型,以安全信息认知过程为主线,以安全信息失真或不对称为问题,构建了1个包含7个关键事件、6个时间状态、5级信息失真和4级信息传播的安全信息认知通用理论模型,阐述了模型的内涵、特点、用途分类和故障诊断分析途径,并由模型推导出1组安全科学基础理论新概念,同时也建立了1种新的安全信息系统分析与控制的方法论。结果表明,该模型对事故致因机理分析、行为安全管理、系统安全设计和事故防控等的具有重要的理论和实际意义。  相似文献   
999.
李军    李庆奇    贺城墙    赵子文    魏状状   《中国安全生产科学技术》2017,13(11):66-72
为了研究危险化学气体泄漏事故扩散过程以及受灾人员疏散规划问题。提出以GIS为“连接器”,将危险化学气体的泄漏和扩散过程模拟、气体扩散风险分析和最优疏散方案生成3个过程进行集成,实现泄漏事故的综合应急响应。研究结果显示:方法能针对各类泄漏事故模拟气体的动态扩散过程,并生成受灾人员疏散规划方案,有助于应急处置机构及时决策,进而减少生命财产的损失。  相似文献   
1000.
随着我国工业现代进程不断深入,安全生产、职业健康和环境保护日益受到重视,很多企业同时建立了安全生产标准化和HSE管理体系,这两种体系同时并存,在一定程度上增加了企业安全管理的复杂程度。为了提高管理效率,集成管理,通过对比分析二者的原理、方法、要素、流程和考核指标等因素,探讨了二者集成管理的可行性,并提出了一种基于信息化技术消除重复管理点,实现集成管理的方法。该方法能实现二者方法、要素和流程的有效集成,管理业务流程的“自动化”和便捷的流程优化再造,不但提高了管理效率,而且也为管理者提供了有效的决策支持。  相似文献   
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