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131.

Concepts of sustainable development have stimulated innovation in the delivery of environmental management. In particular, new partnership approaches have been developed in recognition of the need to adopt more holistic perspectives and facilitate multi-sectoral and cross-sectoral working. River catchments are complex systems and have been one particular focus of experimentation in environmental management mechanisms. This paper provides a brief overview of river management experience in the UK, charting changing approaches in terms of scope and organisation since the 1970s. This sets the context for a more detailed examination of the Mersey Basin Campaign and, in particular, its River Valley Initiatives. The paper concludes with an evaluation of the merits of this approach in relation to sustainable river management.  相似文献   
132.
The Climate Change Act 2008 commits the UK to reducing carbon emissions by 80% of 1990 levels by 2050. With household emissions constituting more than a quarter of current total energy use in the UK, energy practices in the home have taken on increased policy attention. In this paper, we argue that the UK government's approach is founded upon a variant of methodological individualism that assumes that providing greater energy information to individuals will effect behaviour change in relation to energy use. Such an approach is potentially limited in its effectiveness and does not afford appropriate recognition to all those affected by energy policy. In contrast to this approach, we set out an alternative perspective, a community knowledge networks approach to energy and justice which recognises the contexts and relationships in which people live and use energy. Such an approach emphasises situated knowledge and practices in order to gain a greater understanding of how individuals and communities use energy, but, importantly, offers a means for affording greater recognitional justice to different social groups.  相似文献   
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In order to examine the time-dependent effects of pentabrominated diphenyl ether (BDE-99) on thyroid hormones levels and histological structure in rats, 4-week-old SD rats were divided into 10 groups randomly, according to their body weight. Rats in treatment groups were orally gavaged with BDE-99 at the dose of 60 mg kg?1 for 10, 15, 20, 30 or 40 days, while rats in control group received equal volume of corn oil. Serum levels of thyroxine (FT4), triiodothyronine (FT3), and thyroid stimulating hormone (TSH) were measured by radioimmunoassay. Sections of thyroids were dyed with hematoxylin-eosin (HE) to detect any pathologically alterations. In BDE-99 treated groups, on day 10, changes in serum levels of FT4, FT3 and TSH were not found. On days 15 and 20, serum levels of FT4 and FT3 decreased, accompanied by increased levels of TSH. On days 30 and 40, serum levels of these hormones returned to control values. As for alterations in histology, on day 15, follicular epithelium of the thyroid were found to proliferate into two layers in BDE-99 treated rats. On day 20, in focal areas the two-layer follicular epithelia were observed to continuously proliferate into 3–4 layers of follicular epithelium, called hyperplasia plaques. On days 30 and 40, solid buds and secondary follicles to solid buds were detected. The earliest alteration of thyroid hormones in treated SD rats occurred at the duration of 10–15 days, with corresponding histopathologic changes. As the exposure time increased, the serum level of hormones and histopathology altered accordingly in a time-dependent manner.  相似文献   
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Several recent studies have tested the hypothesis that song quality in adult birds may reflect early developmental conditions, specifically nutritional stress during the nestling period. Whilst all of these earlier studies found apparent links between early nutritional stress and song quality, their results disagree as to which aspects of song learning or production were affected. In this study, we attempted to reconcile these apparently inconsistent results. Our study also provides the first assessment of song amplitude in relation to early developmental stress and as a potential cue to male quality. We used an experimental manipulation in which the seeds on which the birds were reared were mixed with husks, making them more difficult for the parents to obtain. Compared with controls, such chicks were lighter at fledging; they were thereafter placed on a normal diet and had caught up by 100 days. We show that nutritional stress during the first 30 days of life reduced the birds’ accuracy of song syntax learning, resulting in poorer copies of tutor songs. Our experimental manipulations did not lead to significant changes in song amplitude, song duration or repertoire size. Thus, individual differences observed in song performance features probably reflect differences in current condition or motivation rather than past condition.  相似文献   
139.
The biological conversion of sulfate from disposed gypsum drywall to hydrogen sulfide (H(2)S) in the anaerobic environment of a landfill results in odor problems and possible health concerns at many disposal facilities. To examine the extent and magnitude of such emissions, landfill gas samples from wells, soil vapor samples from the interface of the waste and cover soil, and ambient air samples, were collected from 10 construction and demolition (C&D) debris landfills in Florida and analyzed for H(2)S and other reduced sulfur compounds (RSC). H(2)S was detected in the well gas and soil vapor at all 10 sites. The concentrations in the ambient air above the surface of the landfill were much lower than those observed in the soil vapor, and no direct correlation was observed between the two sampling locations. Methyl mercaptan and carbonyl sulfide were the most frequently observed other RSC, though they occurred at smaller concentrations than H(2)S. This research confirmed the presence of H(2)S at C&D debris landfills. High concentrations of H(2)S may be a concern for employees working on the landfill site. These results indicate that workers should use proper personal protection at C&D debris landfills when involved in excavation, landfill gas collection, or confined spaces. The results indicate that H(2)S is sufficiently diluted in the atmosphere to not commonly pose acute health impacts for these landfill workers in normal working conditions. H(2)S concentrations were extremely variable with measurements occurring over a very large range (from less than 3 ppbv to 12,000 ppmv in the soil vapor and from less than 3 ppbv to 50 ppmv in ambient air). Possible reasons for the large intra- and inter-site variability observed include waste and soil heterogeneities, impact of weather conditions, and different site management practices.  相似文献   
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This paper explores the nature of the violence that characterises complex humanitarian emergencies and the related implications for modelling livelihoods systems. While noting the importance of livelihoods approaches in complex humanitarian emergencies, it deliberates the limitations of sustainable livelihoods frameworks when applied in environments marked by protracted instability. Adaptations to the model are discussed, with a particular focus on the relationships among violence, assets and liabilities within livelihoods systems. Political economy of violence theories intimate that the assets on which livelihoods systems are constructed in peaceful times may instead become life-and livelihood-threatening liabilities in periods of conflict. Adaptations to livelihood systems in violent settings require that analysts consider violence from policy, institutional and process perspectives. It is suggested that vulnerability should be re-conceptualised as endogenous to livelihoods systems in violent settings. Building on the work of others, a livelihoods model adapted for complex humanitarian emergencies is presented.  相似文献   
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