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   150篇
  免费   5篇
安全科学   9篇
废物处理   16篇
环保管理   22篇
综合类   10篇
基础理论   66篇
污染及防治   20篇
评价与监测   3篇
社会与环境   6篇
灾害及防治   3篇
  2020年   2篇
  2019年   3篇
  2018年   1篇
  2017年   4篇
  2016年   4篇
  2015年   7篇
  2014年   3篇
  2013年   16篇
  2012年   6篇
  2011年   5篇
  2010年   5篇
  2009年   5篇
  2008年   8篇
  2007年   6篇
  2006年   5篇
  2005年   2篇
  2004年   4篇
  2003年   5篇
  2002年   4篇
  2001年   1篇
  2000年   5篇
  1999年   2篇
  1998年   5篇
  1997年   1篇
  1996年   4篇
  1995年   3篇
  1994年   3篇
  1993年   5篇
  1992年   2篇
  1991年   2篇
  1990年   4篇
  1988年   2篇
  1987年   1篇
  1986年   2篇
  1985年   3篇
  1984年   1篇
  1983年   3篇
  1981年   1篇
  1980年   3篇
  1979年   2篇
  1977年   1篇
  1975年   1篇
  1973年   1篇
  1969年   1篇
  1965年   1篇
排序方式: 共有155条查询结果,搜索用时 328 毫秒
131.
Small island communities are inherently coastal communities, sharing many of the attributes and challenges faced by cities, towns and villages situated on the shores of larger islands and continents. In the context of rapidly changing climates, all coastal communities are challenged by their exposure to changing sea levels, to increasingly frequent and severe storms, and to the cumulative effects of higher storm surges. Across the globe, small island developing states, and small islands in larger states, are part of a distinctive set of stakeholders threatened, not only by climate change but also by shifting social, economic, and cultural conditions. C-Change is a collaborative International Community–University Research Alliance (ICURA) project whose goal is to assist participating coastal communities in Canada and the Caribbean region to share experiences and tools that aid adaptation to changes in their physical environment, including sea-level rise and the increasing frequency of extreme weather events associated with climate change. C-Change researchers have been working with eight partner communities to identify threats, vulnerabilities, and risks, to improve understanding of the ramifications of climate change to local conditions and local assets, and to increase capacity for planning for adaptation to their changing world. This paper reports on the knowledge gained and shared and the challenges to date in this ongoing collaboration between science and society.  相似文献   
132.
Objective: Real-world driving studies, including those involving speeding alert devices and autonomous vehicles, can gauge an individual vehicle's speeding behavior by comparing measured speed with mapped speed zone data. However, there are complexities with developing and maintaining a database of mapped speed zones over a large geographic area that may lead to inaccuracies within the data set. When this approach is applied to large-scale real-world driving data or speeding alert device data to determine speeding behavior, these inaccuracies may result in invalid identification of speeding. We investigated speeding events based on service provider speed zone data.

Methods: We compared service provider speed zone data (Speed Alert by Smart Car Technologies Pty Ltd., Ultimo, NSW, Australia) against a second set of speed zone data (Google Maps Application Programming Interface [API] mapped speed zones).

Results: We found a systematic error in the zones where speed limits of 50–60 km/h, typical of local roads, were allocated to high-speed motorways, which produced false speed limits in the speed zone database. The result was detection of false-positive high-range speeding. Through comparison of the service provider speed zone data against a second set of speed zone data, we were able to identify and eliminate data most affected by this systematic error, thereby establishing a data set of speeding events with a high level of sensitivity (a true positive rate of 92% or 6,412/6,960).

Conclusions: Mapped speed zones can be a source of error in real-world driving when examining vehicle speed. We explored the types of inaccuracies found within speed zone data and recommend that a second set of speed zone data be utilized when investigating speeding behavior or developing mapped speed zone data to minimize inaccuracy in estimates of speeding.  相似文献   

133.
Measurements of ambient carbon dioxide (CO2), made at the Continuous Air Monitoring Program station in downtown Cincinnati, Ohio, and at a rural location near Cincinnati are presented and evaluated to determine the significance of CO2 data in urban air quality monitoring programs. Through analysis of rural CO2 data and evaluation of combustion-sources by means of a diffusion model, it is demonstrated that the variation of urban CO2 concentrations around the prevailing atmosphere background level results from combustion-and noncombustion {natural) sources. The concentration from natural sources can be substantial and in fact override the combustion sources. Because it is not yet practical to predict the contribution of natural sources to urban CO2 concentrations, data obtained for-this gas have only limited utility as an index of air quality. Significant statistical relationships between CO2 data and air quality measurements for summer months are shown to result from similar meteorological effects rather than similar sources. A seasonal and spatial variation of ih-ese relationships is postulated and subsequently demonstrated by analysis of CO2 and air quality measurements from New Orleans, Louisiana, and SU Louis, Missouri.  相似文献   
134.
135.
The infiltration of rainfall into contaminated soils and wastes provides the mechanism whereby hazardous chemical and radionuclide constituents of concern are leached and transported to underlying groundwater and potential human and ecological receptors. The application of engineered covers to reduce rainfall infiltration is an approach that is often selected for the remediation of contaminated sites. Evapotranspiration, or water‐balance, cover designs have been shown to be effective ways of preventing infiltration in arid and semiarid climates. This particular design relies on evaporation and vegetative transpiration to reduce potential infiltration to acceptable levels. In this article, we identify and examine the dominant ecological processes that affect the performance of evapotranspiration cover designs. © 2012 Wiley Periodicals, Inc.  相似文献   
136.
137.
Innes JM  Clarke A 《Disasters》1985,9(2):149-154
This paper reports the results of a survey of the physical and mental reactions of a group ( N = 72) of members of the South Australian Metropolitan Fire Service (MFS) who were engaged in fighting the bushfires close to Adelaide, 16th-19th February 1983. A questionnaire, designed to elicit reports on both physical and mental reactions to exposure to the fire, as well as perceptions of several measures of social strain and social support, was administered to the firefighters when they came off duty. The results reported show the possible influence of role strain factors in predicting mental reactions, and also demonstrate what may be mediating effects of perceived social support. The paper also discusses methodological problems affecting this and other studies of the reactions of emergency service personnel to disaster.  相似文献   
138.
Since the 1970s, there has been a global proliferation of environmental courses. The types of courses are described, as are the structures, philosophies and objectives of courses which have stood the test of time. Employment of environmental graduates is discussed. The degree in Australian Environmental Studies (AES) from Griffith University is described and discussed with reference to pitfalls described in the literature. In Australia, there has been an increased demand for graduates in the environmental area. The trend in employers has been widening the field of potential recruits by keeping the degree specification broad and using the duty statements in the advertisements to specify the environmental skills and knowledge required. The number of graduates from AES has increased steadily since the course was established, and despite global and national trends of proliferation of environmental courses and graduates, survey results indicated that graduates from AES are professionally employed in a wide range of employment sectors, with female and male graduates being equally successful in obtaining employment.  相似文献   
139.
Ranunculus spp. are the dominant plants of lowland chalk stream habitats in England. The spatial variability of sediment characteristics (silt–clay, organic matter, total phosphorus and total nitrogen content) within stands of Ranunculus spp. was investigated in 12 rivers in lowland England. Variability was found to be high and there were no discernible differences between samples taken from within Ranunculus and a limited number of samples from bare substrate. For two of these rivers, comparisons were also made between reaches upstream and downstream of waste water treatment works outfalls in terms of the characteristics of the sediments within Ranunculus stands. In one river a clear increase in sediment nutrient, fine and organic material content was observed downstream but in the other there was no consistent difference. Temporal variability was considered for two rivers in the Frome catchment, Dorset, by analysing the monthly variability in sediment organic matter and silt–clay content beneath Ranunculus stands over an annual cycle of growth and die-back. Whilst a clear pattern of fine and organic material retention consistent with seasonal plant growth patterns was evident at one site, the three sites displayed different temporal patterns. This inconsistency is believed to reflect differences in sediment supply at the three sites.  相似文献   
140.
ABSTRACT

Marine spatial planning (MSP) has become the most adopted approach for sustainable marine governance. While MSP has transformative capacity, evaluations of its implementation illustrate large gaps between how it is conceptualised and how it is practiced. We argue that these gaps arise from MSP being implemented through post-political processes. Although MSP has been explored through post-political lenses, these evaluations are incomplete and do not provide sufficient detail about the complex nature of the post-political condition. Drawing on seminal literature, we conceptualise the post-political as consisting of highly interconnected modalities of depoliticisation, including: neoliberalism; choreographed participation; path dependency; technocratic-managerialism; and the illusion of progressive change. Using these modalities as an analytical framework, we evaluate English MSP and find that it focuses on entrenching neoliberal logic through: tokenistic participation; wholescale adoption of path-dependent solutions; obstructionist deployment of inactive technological solutions; and promising progressive change. We do not, however, view the post-political condition as unresolvable and we develop a suite of suggestions for the re-politicisation of MSP which, collectively, could form the basis for more radical forms of MSP.  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