首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   29733篇
  免费   334篇
  国内免费   247篇
安全科学   999篇
废物处理   1453篇
环保管理   3941篇
综合类   4469篇
基础理论   7748篇
环境理论   8篇
污染及防治   7348篇
评价与监测   2125篇
社会与环境   2043篇
灾害及防治   180篇
  2023年   140篇
  2022年   261篇
  2021年   319篇
  2020年   195篇
  2019年   243篇
  2018年   435篇
  2017年   460篇
  2016年   719篇
  2015年   531篇
  2014年   854篇
  2013年   2463篇
  2012年   1015篇
  2011年   1349篇
  2010年   1102篇
  2009年   1144篇
  2008年   1410篇
  2007年   1329篇
  2006年   1207篇
  2005年   1079篇
  2004年   1037篇
  2003年   990篇
  2002年   933篇
  2001年   1091篇
  2000年   768篇
  1999年   482篇
  1998年   363篇
  1997年   383篇
  1996年   397篇
  1995年   465篇
  1994年   394篇
  1993年   343篇
  1992年   376篇
  1991年   355篇
  1990年   326篇
  1989年   322篇
  1988年   295篇
  1987年   241篇
  1986年   247篇
  1985年   247篇
  1984年   267篇
  1983年   254篇
  1982年   268篇
  1981年   221篇
  1980年   165篇
  1979年   181篇
  1978年   162篇
  1977年   133篇
  1975年   137篇
  1973年   167篇
  1972年   142篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
611.
612.
613.
614.
Large scale sugarcane bagasse storage in uncovered stockpiles has the potential to result in adverse impacts on the environment and surrounding communities through hazards associated with nuisance dust, groundwater seepage, spontaneous combustion and generation of contaminated leachates. Managing these hazards will assist in improved health and safety outcomes for factory staff and reduced potential environmental impacts on surrounding communities. Removal of the smaller fibres (pith) from bagasse prior to stockpiling reduced the dust number of bagasse by 50% and modelling suggests peak ground level PM10 dust emissions would reduce by 70%. Depithed bagasse has much lower water holding capacity (~43%) than whole bagasse.This experimental and modelling study investigated the physical properties of depithed and whole bagasse. Dust dispersion modelling was undertaken to determine the likely effects associated with storage of whole and depithed sugarcane bagasse.  相似文献   
615.
We undertake three objectives in this Incubator. We begin with a discussion of how well‐being has been considered in organizational research. Second, we provide an overview of the relationship between employee well‐being and such workplace outcomes as job performance, employee retention, and cardiovascular health. Third, we introduce exciting research directions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
616.
ProblemResearch on workplace safety has not examined implications for business performance outcomes such as customer satisfaction.MethodIn a U.S. electric utility company, we surveyed 821 employees in 20 work groups, and also had access to archival safety data and the results of a customer satisfaction survey (n = 341).ResultsIn geographically-based work units where there were more employee injuries (based on archival records), customers were less satisfied with the service they received. Safety climate, mediated by safety citizenship behaviors (SCBs), added to the predictive power of the group-level model, but these two constructs exerted their influence independently from actual injuries. In combination, two safety-related predictor paths (injuries and climate/SCB) explained 53% of the variance in customer satisfaction.DiscussionResults offer preliminary evidence that workplace safety influences customer satisfaction, suggesting that there are likely spillover effects between the safety environment and the service environment. Additional research will be needed to assess the specific mechanisms that convert employee injuries into palpable results for customers.Impact on IndustryBetter safety climate and reductions in employee injuries have the potential to offer payoffs in terms of what customers experience.  相似文献   
617.
I am very pleased to have this opportunity to present these thoughts on my personal relationship with Trevor Kletz and the impact he has had on my own career in the field of process safety.  相似文献   
618.
Forty-two communities in rural Alaska are considered unserved or underserved with water and sewer infrastructure. Many challenges exist to provide centralized piped water and sewer infrastructure to the homes, and they are exacerbated by decreasing capital funding. Unserved communities in rural Alaska experience higher rates of disease, supporting the recommendation that sanitation infrastructure should be provided. Organizations are pursuing alternative solutions to conventional piped water and sewer in order to maximize water use and reuse for public health. This paper reviews initiatives led by the State of Alaska, the Alaska Native Tribal Health Consortium, and the Yukon Kuskokwim Health Corporation to identify and develop potential long-term solutions appropriate and acceptable to rural communities. Future developments will likely evolve based on the lessons learned from the initiatives. Recommendations include Alaska-specific research needs, increased end-user participation in the design process, and integrated monitoring, evaluation, and information dissemination in future efforts.  相似文献   
619.
The little auk is the most numerous seabird in the North Atlantic and its most important breeding area is the eastern shores of the North Water polynya. Here, a population of an estimated 33 million pairs breeds in huge colonies and significantly shapes the ecosystem. Archaeological remains in the colonies document that the little auk has been harvested over millennia. Anthropological research discloses how the little auk has a role both as social engineer and as a significant resource for the Inughuit today. The hunting can be practiced without costly equipment, and has no gender and age discrimination in contrast to the dominant hunt for marine mammals. Little auks are ecological engineers in the sense that they transport vast amounts of nutrients from sea to land, where the nutrients are deposited as guano. Here, the fertilized vegetation provides important foraging opportunities for hares, geese, fox, reindeer, and the introduced muskox. We estimate that the relative muskox density is ten times higher within 1 km of little auk fertilized vegetation hotspots.  相似文献   
620.
Winter manure application elevates nutrient losses and impairment of water quality as compared to manure applications in other seasons. In conjunction with reviewing global distribution of animal densities, we reviewed worldwide mandatory regulations and voluntary guidelines on efforts to reduce off-site nutrient losses associated with winter manure applications. Most of the developed countries implement regulations or guidelines to restrict winter manure application, which range from a regulative ban to guidelines based upon weather and field management conditions. In contrast, developing countries lack such official directives, despite an increasing animal production industry and concern over water quality. An analysis of five case studies reveals that directives are derived from a common rationale to reduce off-site manure nutrient losses, but they are also affected by local socio-economic and biophysical considerations. Successful programs combine site-specific management strategies along with expansion of manure storage to offer farmers greater flexibility in winter manure management.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号