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111.
In countries having limited resources, it is difficult to assess urban air quality on contemporaneously, due to the absence of on-line information about air pollution levels and emission rates. An alternative approach is recommended for smaller cities with lower demands of resources. The applied scheme consists of a database of air pollution sources (NO x and CO from industry, traffic, and domestic heating), the simple Gaussian-plume model AEROPOL and a series of measurements by passive monitors. This method was used in Tartu, a small city situated in the valley of the river Emajõgi, within a landscape with noteworthy topographical variations. Simulations of annual average and maximal concentrations were performed, and a fair agreement obtained with NO2 monitoring results from passive Palmes monitors. Inventories of pollution sources in 1998 revealed that official statistics of stationary sources covered 64% of SO2,36% of CO, 37% of NO x and 32% of total particulate matter emissions. Recommendations for measures for reducing air pollution levels and for further investigations towards improving air quality assessment and management, are given.  相似文献   
112.
This paper draws upon the DISCUS (Developing Institutional and Social Capacity for Sustainable Development) research project, co-funded by the European Commission. The project was undertaken during 2001 – 2004 and involved an in-depth study of 40 European towns and cities in order to understand the institutional and social factors and conditions that might contribute to policy ‘achievement' or ‘failure' in local sustainable development policy and practice. Based on the findings of this research it proposes a conceptual framework for local sustainable development, linking the concepts of institutional capital, social capital and governance to provide a model for understanding the governing of local sustainability. The research shows that in those cases that exhibit sustainable development policy achievements, there are also greater levels of civil society activity and knowledge regarding sustainability issues, and high levels of institutional capacity. Confident local government is crucial to the development of institutional capacity and to institutional learning. One aspect of this is local authorities being equipped to address the longer-term issues and to have a strategic vision for a sustainable future.  相似文献   
113.
Keskinen M 《Ambio》2008,37(3):193-198
The Mekong River Basin is facing rapid changes, including intensive plans for water development. While the different development projects are considered to be important for economic development, the negative impacts that they are likely to cause for ecosystems and livelihoods are estimated to be remarkable. Yet, existing impact assessment processes seem in many cases to be inadequate to capture even the actual magnitude of the impacts at different levels. This article looks at the different impact assessment processes and their challenges in the basin. It is argued that impact assessment in this kind of dynamic and complex setting requires better coordination between assessments at different levels. Basinwide impact assessment would benefit from a more adaptive, multilevel approach that makes better use of assessments from local levels up to the regional level and builds on more participatory and interdisciplinary methods. Successful impact assessment also requires the recognition of the highly political nature of water development and related planning processes.  相似文献   
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115.
It is well recognized that a trigger point is a functional, rather than an anatomical, entity. It is known that a significant fraction of both acute and chronic pain experience is myofascial in nature. This paper is aimed to discuss the potential of using permanent magnets placed over the trigger points, which are associated with that referred pain, to be a tool for pain relief. This approach is even more important in patients with various disabilities and experiencing chronic sacro-iliac and/or low back pain. It appears that the trigger points represent a plausible physiological/tissue “window” and/or pathways, which allow the magnetic fields to penetrate through physiological barriers, and thus returning injured tissues to the homeostatic state. These “tissue windows” represent physiological “entrance points” for eventual exogenous stimulations, mainly physical by nature, to enter the body. There is evidence that the application of magnetic fields (via permanent magnets) on trigger points is more effective for pain relief as compared to application to other body surface area. The systemic effects at which the results are manifested at sites distant from application area is also considered when discussing effects of magnetic fields applied on trigger points. Ion transport is considered as central to the integrity and proper functioning of nerve excitability and muscle contraction. Any disruption of their normal function would directly and markedly affect human neurosensory and neuromotor performance. Biophysical phenomena associated with modification of ion transport are in the range of weak stimuli. Therefore, electrophysiological changes in the functions of the so-called ion channels, are among the more (perhaps the most) sensitive indicators to detect and quantify physiological effects of electromagnetic fields.  相似文献   
116.
This article highlights recent research on the beneficial use of selected low frequency electromagnetic fields (EMF) as a safe alternative therapy for treatment of cancer and other health problems. It is shown that EMF therapy provides a safe alternative and adjunct modality for the treatment of cancer and other health problems, and therefore, research in this field deserves more support. The paper also discusses some reports and hypothesis of potential risk of human exposure to low frequency EMF, mainly to the power line frequency of 60 Hz.  相似文献   
117.
Indirect exploitative competition, direct interference and predation are important interactions affecting species coexistence. These interaction types may overlap and vary with the season and life-history state of individuals. We studied effects of competition and potential nest predation by common shrews (Sorex araneus) on lactating bank voles (Myodes glareolus) in two seasons. The species coexist and may interact aggressively. Additionally, shrews can prey on nestling voles. We studied bank vole mothers’ spatial and temporal adaptations to shrew presence during summer and autumn. Further, we focused on fitness costs, e.g. decreased offspring survival, which bank voles may experience in the presence of shrews. In summer, interference with shrews decreased the voles’ home ranges and they spent more time outside the nest, but there were no effects on offspring survival. In autumn, we found decreased offspring survival in enclosures with shrews, potentially due to nest predation by shrews or by increased competition between species. Our results indicate a shift between interaction types depending on seasonal constraints. In summer, voles and shrews seem to interact mainly by interference, whereas resource competition and/or nest predation by shrews gain importance in autumn. Different food availability, changing environmental conditions and the energetic constraints in voles and shrews later in the year may be the reasons for the varying combinations of interaction types and their increasing effects on the inclusive fitness of bank voles. Our study provides evidence for the need of studies combining life history with behavioural measurements and seasonal constraints.  相似文献   
118.
Environmental Chemistry Letters - Research on plastic pollution has recently evidenced the ubiquitous presence of tiny plastic particles called microplastics. Microplastics alter organisms because...  相似文献   
119.
We summarize the patterns of 137Cs activity concentrations and transfer into fish and other biota in four small forest lakes in southern Finland during a twenty-year period following the Chernobyl accident in April 1986. The results from summer 1986 showed fastest accumulation of 137Cs into planktivorous fishes, i.e. along the shortest food chains. Since 1987, the highest annual mean values of 137Cs have been recorded in fish occupying the highest trophic levels, for perch (Perca fluviatilis) 13,600 Bq/kg (ww) and for pike (Esox lucius) 20,700 Bq/kg (ww). At the same time, activity concentrations of 137Cs in crustacean zooplankton and Asellus aquaticus have ranged between 1000 and 19,500 Bq/kg (dw). In 2006, 5-28% of the 1987 137Cs activity concentration levels were still present in perch and pike. Since 1989 their 137Cs activity concentrations in oligohumic seepage lakes have remained significantly higher than in polyhumic drainage lakes due to the increased transfer of 137Cs into fish in the seepage lakes with lower electrolyte concentrations, longer water retention times and lower sedimentation rate.  相似文献   
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