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   527篇
  免费   19篇
  国内免费   8篇
安全科学   326篇
废物处理   2篇
环保管理   33篇
综合类   77篇
基础理论   12篇
环境理论   2篇
污染及防治   21篇
评价与监测   34篇
社会与环境   31篇
灾害及防治   16篇
  2023年   3篇
  2022年   5篇
  2021年   12篇
  2020年   14篇
  2019年   25篇
  2018年   8篇
  2017年   15篇
  2016年   32篇
  2015年   20篇
  2014年   23篇
  2013年   29篇
  2012年   32篇
  2011年   37篇
  2010年   35篇
  2009年   36篇
  2008年   32篇
  2007年   41篇
  2006年   34篇
  2005年   20篇
  2004年   11篇
  2003年   16篇
  2002年   7篇
  2001年   8篇
  2000年   7篇
  1999年   6篇
  1998年   12篇
  1997年   3篇
  1996年   3篇
  1995年   5篇
  1994年   2篇
  1993年   5篇
  1992年   3篇
  1991年   1篇
  1989年   3篇
  1987年   1篇
  1986年   1篇
  1985年   1篇
  1983年   3篇
  1982年   2篇
  1979年   1篇
排序方式: 共有554条查询结果,搜索用时 15 毫秒
451.
大亚湾核电站运转前及运转后大鹏澳海域水质状况评价   总被引:7,自引:1,他引:7  
根据大亚湾核电站运转前及运转后对大亚湾大鹏澳海域的监测资料,选用pH,DO,CODMn,TIN,PO4-P和Chl.a为评价因子,以水质质量综合系数(WQI)为模式,评价了大鹏澳海域水体质量状况。综合评价的结果显示,大鹏澳海域水体质量,在核电站运转前及运转后,冬,夏季节均属清洁水平。  相似文献   
452.
我国核能利用与能源可持续发展探讨   总被引:1,自引:0,他引:1  
阐述了我国目前的能源利用状况,火电与核电对环境影响的比较,核废物的处理技术及核电的安全性等,指出大力发展高效清洁的核电是我国实施可持续发展战略的必然要求。  相似文献   
453.
Numerous challenges face those involved with developing a coordinated and consistent approach to cleaning up the US Department of Energy’s (DOE) Hanford Site in southeastern Washington. These challenges are much greater than those encountered when the site was selected and the world’s first nuclear complex was developed almost 50 years ago. This article reviews Hanford’s history, operations, waste storage/disposal activities, environmental monitoring, and today’s approach to characterize and clean up Hanford under a Federal Facility Agreement and Consent Order, signed by DOE, the Environmental Protection Agency, and the Washington Sate Department of Ecology. Although cleanup of defense-related waste at Hanford holds many positive benefits, negative features include high costs to the US taxpayer, numerous uncertainties concerning the technologies to be employed and the risks involved, and the high probability that special interest groups and activists at large will never be completely satisfied. Issues concerning future use of the site, whether to protect and preserve its natural features or open it to public exploitation, remain to be resolved.  相似文献   
454.
在地震危险性概率方法应用的基础上,本文对影响核电厂场址地震危险性评定值的四个重要因素,诸如工作区潜在震源区的判定、地震活动性的时空非均匀性、地震动衰减关系及其衰减模型进行了讨论和改进,提出了一个核电厂场址地震危险性评定的方法。应用该法可提高核电厂场址地震危险性评定的可靠性和显著的经济效益。文中还讨论了地震构造法对核电厂场址地震危险性评定的应用。最后,应用本文提供的2种方法,对秦山核电厂场址进行了地震危险性评定,选取2种方法中的最大值即为核电厂场址地震危险性的评定值。  相似文献   
455.
The recent events at Chernobyl have again brought the issues of nuclear safety to the forefront of the nuclear power debate. Fortunately, our experience with such incidents has been very limited, but it is important to learn as much as possible from such events so as to minimize the cost and effect of any other nuclear incidents, be they small or large. Much of the discussion about the possible effects of nuclear incidents has centered around the human cost in terms of health. While this is undoubtedly of paramount concern, the effect of the release of radiation from Chernobyl on the agricultural resource base in Europe can provide valuable insights on how to reduce the costs associated with the contamination of agricultural areas. This article outlines some of the lessons that can be learned using the livestock-raising industry in northern Wales as an example.  相似文献   
456.
Objective: We conducted a cohort study of recent wartime veterans to determine the postservice mortality risk due to motor vehicle accidents (MVAs).

Methods: Veterans were identified from the Defense Manpower Data Center records. Deployment to te Iraq or Afghanistan war zone was determined from the Contingency Tracking System. Vital status of 317,581 deployed and 964,493 nondeployed veterans was followed from their discharge dates between 2001 to 2007 until earlier of date of death or December 31, 2009. Underlying causes of death were obtained from the National Death Index Plus.

Results: Based on 9,353 deaths (deployed, 1,650; nondeployed, 7,703), of which 779 were MVA deaths as drivers (166; 613), both cohorts had 25 to 24% lower mortality risk from all causes but had 44 to 45% higher risk of MVA deaths relative to the U.S. general population. The higher MVA mortality risk was not associated with deployment to the war zone. After controlling for age, sex, race, marital status, branch of service, and rank, the risk for deployed veterans was comparable to that of nondeployed veterans (hazard ratio = 0.91; 95% confidence interval, 0.77–1.09).

Conclusions: Veterans exhibit significantly higher risk of MVA deaths compared to the U.S. general population. However, deployment to the Iraq or Afghanistan war was not associated with the excess risk.  相似文献   

457.
Objective: A zero tolerance alcohol restriction law was adopted in Brazil in 2008. In order to assess the effectiveness of this intervention, the present study compares specific mortality in 2 time series: 1980–2007 and 2008–2013.

Methods: Data on mortality and population were gathered from official Brazilian Ministry of Health information systems. Segmented regression analyses were carried out separately for 3 major Brazilian capitals: Belo Horizonte, Rio de Janeiro, and São Paulo.

Results: In 2 cities (Belo Horizonte and Rio de Janeiro) there were no significant changes in mortality rate trends in 2 periods, 1980 to 2007 and 2008 to 2013, where the observed rates did not differ significantly from predicted rates. In São Paulo, a decreasing trend until 2007 unexpectedly assumed higher levels after implementation of the law.

Conclusion: There is no evidence of reduced traffic-related mortality in the 3 major Brazilian capitals 5.5 years after the zero tolerance drinking and driving law was adopted.  相似文献   

458.
Objective: The main objective of this study is to identify the main factors associated with injury severity of vulnerable road users (VRUs) involved in accidents at highway railroad grade crossings (HRGCs) using data mining techniques.

Methods: This article applies an ordered probit model, association rules, and classification and regression tree (CART) algorithms to the U.S. Federal Railroad Administration's (FRA) HRGC accident database for the period 2007–2013 to identify VRU injury severity factors at HRGCs.

Results: The results show that train speed is a key factor influencing injury severity. Further analysis illustrated that the presence of illumination does not reduce the severity of accidents for high-speed trains. In addition, there is a greater propensity toward fatal accidents for elderly road users compared to younger individuals. Interestingly, at night, injury accidents involving female road users are more severe compared to those involving males.

Conclusions: The ordered probit model was the primary technique, and CART and association rules act as the supporter and identifier of interactions between variables. All 3 algorithms' results consistently show that the most influential accident factors are train speed, VRU age, and gender. The findings of this research could be applied for identifying high-risk hotspots and developing cost-effective countermeasures targeting VRUs at HRGCs.  相似文献   

459.
This article examines online discourse in 2011 surrounding the proposed Duke Energy and Progress Energy merger in the Carolinas. It explores how issues pertaining to the merger, including constructing new nuclear plants, are discussed in media coverage and by citizens using social media. Overall, we find that the merger discourse focuses on economic concerns rather than the environmental concerns we had anticipated. However, post-Fukushima discourse appears to have become more inclusive of environmental concerns. We conclude that environmental discussions and efforts are likely to be globally informed andlocally situated, discussing the implications for environmental communication research exploring online discourses, specifically through social media. Future research must address how to locate and delineate constellations of locally situated discourse to provide a clearer picture of environmentally focused social media communication.  相似文献   
460.
This essay examines discourse from members of the Skull Valley Goshute Native American tribe about the nuclear-waste proposal and tribal controversy. Building from Kinsella's “bounded-constitutive” theoretical model of communication, I argue the environment (material) is more than a context where Goshute culture and policy development (symbolic) plays out. Rather, environment, culture, and policy mutually define each other, and the material environment constrains Goshute culture. Instead of the symbolic unilaterally influencing the material, the material responds and acts to influence the symbolic. The symbolic becomes responsible to the material and vice versa as the relationship is multi-influential and interactive creating political, cultural, and environmental complexities and contradictions while fueling intra-tribal conflict.  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