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   1038篇
  免费   83篇
  国内免费   12篇
安全科学   202篇
废物处理   11篇
环保管理   379篇
综合类   232篇
基础理论   94篇
环境理论   14篇
污染及防治   14篇
评价与监测   18篇
社会与环境   111篇
灾害及防治   58篇
  2024年   3篇
  2023年   14篇
  2022年   18篇
  2021年   28篇
  2020年   26篇
  2019年   34篇
  2018年   39篇
  2017年   55篇
  2016年   75篇
  2015年   63篇
  2014年   43篇
  2013年   95篇
  2012年   47篇
  2011年   68篇
  2010年   57篇
  2009年   50篇
  2008年   54篇
  2007年   52篇
  2006年   61篇
  2005年   61篇
  2004年   28篇
  2003年   25篇
  2002年   17篇
  2001年   14篇
  2000年   14篇
  1999年   17篇
  1998年   2篇
  1997年   3篇
  1996年   3篇
  1995年   4篇
  1993年   2篇
  1991年   4篇
  1990年   1篇
  1989年   6篇
  1988年   3篇
  1987年   3篇
  1986年   2篇
  1984年   2篇
  1983年   2篇
  1982年   3篇
  1981年   2篇
  1980年   4篇
  1979年   6篇
  1978年   1篇
  1977年   4篇
  1975年   2篇
  1974年   1篇
  1973年   5篇
  1972年   2篇
  1971年   6篇
排序方式: 共有1133条查询结果,搜索用时 406 毫秒
951.
Consumer pressure is usually considered as one of the major drivers for more environmental friendly products. During the last decade an increasing focus on public procurement has emerged as an important contributor to that pressure. In this paper we focus on the role of municipalities and counties in green public procurement. Based on surveys we investigate to what degree green public procurement is implemented in Norwegian municipalities and counties and which capabilities are critical for successful green procurement. We both investigate to what degree environmental information is requested in call for tenders and also to what degree the information is actually used in the final selection of supplier. The information gathered from the municipalities and counties is compared with information obtained from potential suppliers to see if suppliers and purchasers agree on the importance of environmental demands in the selection of suppliers.  相似文献   
952.
土地征收中的公共利益在现行立法中的表述具有极大的模糊性,从土地征收、土地征收中界定公共利益的若干原则及可行性方案等几个方面进行论述,以期解决这个司法审查和行政执法中棘手的问题。  相似文献   
953.
Conservation practitioners must contend with an increasing array of threats that affect biodiversity. Citizen scientists can provide timely and expansive information for addressing these threats across large scales, but their data may contain sampling biases. We used randomization procedures to account for possible sampling biases in opportunistically reported citizen science data to identify species’ sensitivities to human land use. We analyzed 21,044 records of 143 native reptile and amphibian species reported to the Carolina Herp Atlas from North Carolina and South Carolina between 1 January 1990 and 12 July 2014. Sensitive species significantly associated with natural landscapes were 3.4 times more likely to be legally protected or treated as of conservation concern by state resource agencies than less sensitive species significantly associated with human‐dominated landscapes. Many of the species significantly associated with natural landscapes occurred primarily in habitats that had been nearly eradicated or otherwise altered in the Carolinas, including isolated wetlands, longleaf pine savannas, and Appalachian forests. Rare species with few reports were more likely to be associated with natural landscapes and 3.2 times more likely to be legally protected or treated as of conservation concern than species with at least 20 reported occurrences. Our results suggest that opportunistically reported citizen science data can be used to identify sensitive species and that species currently restricted primarily to natural landscapes are likely at greatest risk of decline from future losses of natural habitat. Our approach demonstrates the usefulness of citizen science data in prioritizing conservation and in helping practitioners address species declines and extinctions at large extents.  相似文献   
954.
《组织行为杂志》2017,38(7):950-976
The client relationships and tacit knowledge of professionals are professional service firms' (PSFs') major value creating resources producing challenges in generating post‐merger and acquisition value and risks of reducing the productivity or losing key professionals and their clients. The recent emergence of publicly owned PSFs and rapid growth through consolidating smaller privately owned firms potentially increases this risk by integrating small firms and their professionals into large public companies that may be governed very differently. This study explores post‐acquisition integration processes: professional behaviours and associated performance implications in two highly acquisitive publicly owned accounting companies. In one company, the integration process was rapid and heavily directed by senior management, while in the second company, integration was more gradual, initially undirected but then facilitated by senior management. The findings suggest that integration processes can impact the behaviour of professionals and acquiring firm performance. This research contributes to the understanding of post‐acquisition integration processes in PSFs and decision‐making and professional behaviour in recently emerged publicly owned PSFs. The study contributes to knowledge‐based theory by identifying factors that can affect the decision authority of executives and how organisational behaviour can constrain the implementation of executive integration decisions. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
955.
Disasters and displacement increasingly affect and challenge urban settings. How do pregnant women fare in the aftermath of a major disaster? This paper investigates the effect of pregnancies in disaster situations. The study tests a hypothesis that pregnant women residing in hurricane‐prone areas suffer higher health risks. The setting is Louisiana in the Gulf Coast, United States, a state that continually experiences hurricane impacts. The time period for the analysis is three years following the landfall of Hurricane Andrew in 1992. We analysed low birth weight and preterm deliveries before and after landfall, as a whole and by race. Findings support an association between hazards and health of a community and indicate that pregnant women in the affected area, irrespective of race, are more likely to experience preterm deliveries compared to pre‐event births. Results suggest there is a negative health legacy impact in Louisiana as a result of hurricane landfall.  相似文献   
956.
为揭示对向公交换乘距离与换乘乘客横穿道路的相互关系,约请272名受试者,完成城市公交汽车换乘试验。基于换乘试验统计出横穿马路人数,采用非参数估计方法估计换乘乘客的最大忍耐换乘距离,利用SPSS软件,构建拟合程度最高的对向换乘生存距离二次项函数模型,并对模型的有效性进行验证。结果表明,违规过街行人数随公交换乘距离的增大而增多;生存率随换乘距离的增大呈现"缓慢减小-迅速减小-平缓减小"的变化趋势,换乘距离增加至126 m后,越来越多的乘客难以接受这样的距离;换乘距离相同时,男性相比女性更容易横穿马路;根据构建的对向公交换乘生存距离模型,85%的换乘乘客可接受的换乘距离为124 m,50%的换乘乘客可接受的换乘距离为174 m。  相似文献   
957.
958.
Lion (Panthera leo) populations are in decline throughout most of Africa. The problem is particularly acute in southern Kenya, where Maasai pastoralists have been spearing and poisoning lions at a rate that will ensure near term local extinction. We investigated 2 approaches for improving local tolerance of lions: compensation payments for livestock lost to predators and Lion Guardians, which draws on local cultural values and knowledge to mitigate livestock‐carnivore conflict and monitor carnivores. To gauge the overall influence of conservation intervention, we combined both programs into a single conservation treatment variable. Using 8 years of lion killing data, we applied Manski's partial identification approach with bounded assumptions to investigate the effect of conservation treatment on lion killing in 4 contiguous areas. In 3 of the areas, conservation treatment was positively associated with a reduction in lion killing. We then applied a generalized linear model to assess the relative efficacy of the 2 interventions. The model estimated that compensation resulted in an 87–91% drop in the number of lions killed, whereas Lion Guardians (operating in combination with compensation and alone) resulted in a 99% drop in lion killing. Eficacia de Dos Programas de Conservación de Leones en Maasailand, Kenia  相似文献   
959.
为了解北京市公共场所室内甲醛污染水平及影响因素,在工作日和周末上下午对北京市内家具市场、综合商场和服装批发市场3类公共场所不同功能区的室内甲醛浓度进行监测和分析。结果表明:家具市场中包含木质家具的功能区甲醛浓度最高;服装批发市场中包含外贸针织功能区的甲醛浓度最高;综合商场中包含化妆品功能区的甲醛浓度最高;服装批发市场和家具市场整体的甲醛浓度已超过《商场(店)、书店卫生标准》(GB 9670—1996)规定的限值0.12mg/m3。3类公共场所甲醛点位超标率服从显著性水平p0.05的χ2双侧检验,具有统计学意义。长期暴露在服装批发市场和家具市场内的工作人员和顾客,可能存在健康风险,应对家具市场、服装批发市场的甲醛污染进行控制。  相似文献   
960.
Non‐pharmaceutical interventions (NPIs) are an important public health tool for responding to infectious disease outbreaks, including pandemics. However, little is known about the individual characteristics associated with support for NPIs, or whether they are consistent across regions. This study draws on survey data from four regions—Hong Kong, Singapore, Taiwan, and the United States—collected following the Severe Acute Respiratory Syndrome (SARS) outbreak of 2002–03, and employs regression techniques to estimate predictors of NPI support. It finds that characteristics associated with NPI support vary widely by region, possibly because of cultural variation and prior experience, and that minority groups tend to be less supportive of NPIs when arrest is the consequence of noncompliance. Prior experience of face‐mask usage also results in increased support for future usage, as well as other NPIs. Policymakers should be attentive to local preferences and to the application of compulsory interventions. It is speculated here that some public health interventions may serve as ‘gateway’ exposures to future public health interventions.  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