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631.
Abstract

Dietary administration of β‐ and α‐hexachlorocyclohexane (HCH) to albino rats caused an abnormal excessive excretion of glucose in the urine, blood glucose level being nearly normal. Occurrence of glucosuria was also accompanied by increased excretions of the two low‐threshold compounds ‐ creatinine and urea, their levels in blood being normal. The interference of HCH isomers with renal function as evidenced by biochemical data was also indicated by histopathological lesions observed in the kidney sections, viz., hypertrophy and degeneration of the renal tubular epithelia.  相似文献   
632.
Abstract

Strigol (1) is a natural product that triggers suicidal germination of parasitic Striga species. Here we present an improved annulation sequence for the synthesis of the tricyclic moieties of strigol and its analogues. Our approach makes use of the one‐pot cyclization of 5‐nitro‐2‐pentanone and cyclopent‐2‐enone diesters to afford 7‐methyl‐4‐nitro‐l‐oxo‐hydrindene derivatives. Functional group elaboration of these intermediates leads to a series of hydrindene‐2‐acetic and propionic acids.  相似文献   
633.
Abstract

Adult New Zealand white does were intubated orally with single daily doses of 0, 5, or 10 mg of photomirex (8‐monohydromirex) per kg body weight from the 6th through to the 18th day of gestation. Pregnancies were interrupted at term by cesarian section and fetuses removed and evaluated by following routine teratologic methods. Both maternal and fetal tissues were analyzed for residues of photomirex. None of the treated does showed any sign of toxicity. Except for a significant reduction in the mean fetal weight of the 10 mg/kg group all other parameters which evaluated fetal survival and fetal development were within the control range. Photomirex was found in all tissues examined. In the doe, the highest levels were found in fat followed by liver, kidney, spleen, heart, brain and blood. Photomirex was readily transferred across the placenta and accumulated in the fetus. However, in the fetus the highest levels were found in the heart, followed by liver, brain and blood. There were no teratogenic effects at the doses used in this study.  相似文献   
634.
In recent years, due to growing environmental concern, there has been an increasing attention to product take‐back, product recovery and the re‐distribution of end‐of‐life products. Reverse logistics (RL), which refers to the distribution activities involved in product returns, has recently received much attention because many companies are using it as a strategic tool to serve their customers; and can generate good revenue. The management of return flow usually requires a specialised infrastructure with special information systems for tracking and dedicated equipment for the processing of returns. An efficient reverse distribution structure may lead to a significant return on investment as well as a significantly increased competitiveness in the market. Therefore, the time seems to be right for a systematic overview of various issues that are arising in the context of reverse distribution. The main purpose of this paper is to review the literature on RL and suggest a classification based on reverse distribution issues. The result of this research provides a better understanding of the RL concept and outlines some future directions of research on modelling and analysis.  相似文献   
635.
636.
One of the key features of environmentally conscious manufacturing has been the efforts to promote product recycling and remanufacturing. Efficient material re‐utilisation through product disassembly to retrieve the desired parts and/or subassemblies is one rational approach. This is because it can promote the conservation of both material and energy resources whilst concurrently reducing environmental impact. However, because manufactured products may be made from many components, disassembly load becomes a critical factor that may obstruct the recovery of materials. Accordingly, it is essential to develop a practical method for deriving a disassembly plan to decrease such load, and to endow a certain value to the product at the end of its life cycle. With this understanding, the authors have developed a practical procedure to produce an adaptive disassembly strategy. The authors have applied a meta‐heuristic method known as genetic programming (GP) as a search engine to derive the adaptive disassembly sequence together with a multi‐objective optimisation method termed MOON2R. The authors have also proposed a hierarchical sequencing method to cope with large/complex products and added several ideas to increase the applicability associated with the interests in disassembly of hazardous and/or valuable parts, and alternative disassembly actions. Through numerical experiments, the authors examined the effectiveness of the proposed approach by showing its support for relevant planning and design decisions for product recycling and remanufacturing from various viewpoints.  相似文献   
637.
This paper explores a fruitful convergence between the distributive and procedural dimensions of environmental justice theory and current debates in the field of development studies over capitals and capabilities, institutions, and discourse formation to shed new light on natural resource management projects in the developing world. Specifically, we document the planning and implementation of two types of water interventions in two contrasting regions: watershed development programmes in northeast India and small reservoirs in sub‐Saharan West Africa. We find that there is a contradiction between the inherently political nature of water interventions and the fact that such projects remain grounded in apolitical, technical and managerial narratives. In contrast to the new semantic of development, this depoliticization results in the near absence of attention paid to procedural (participation and empowerment) and distributive (equity) justice concerns and in local actors having to revert to covert ways to achieve their ends. A constructive dialogue between development studies and environmental justice scholars can offer a fresh look on the society‐environment nexus in the developing world.  相似文献   
638.
Previous research has shown that customer‐related social stressors (CSS) have negative effects on service providers' long‐term well‐being. Little is known, however, about short‐term and mid‐term affective stress reactions and reciprocal effects between service providers' affect and CSS. The aim of this study was to expand extant research (i) by analyzing service providers' short‐term (across a day) and mid‐term (across 2 weeks) affective reactions to perceived CSS; (ii) by analyzing intraindividual as well as interindividual effects; and (iii) by investigating reciprocal effects of affective reactions and CSS that may eventually lead to psychosocial cycles. Our study employed a diary design with three measurement occasions per day over five consecutive days and a two‐week panel design using a sample of employees from public service organizations (N = 106). Results showed that CSS elicit changes in service providers' short‐term and mid‐term negative affects. We also found support for reversed effects of service providers' affective reactions on experienced CSS indicating psychosocial cycles between customers and service providers. To prevent escalation, we discuss potential resources. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
639.
McMahon, Tyler G. and Mark Griffin Smith, 2012. The Arkansas Valley “Super Ditch”— An Analysis of Potential Economic Impacts. Journal of the American Water Resources Association (JAWRA) 00(0):000‐000. 1‐12. DOI: 10.1111/jawr.12005 Abstract: In Colorado’s Arkansas River basin, urban growth and harsh farming conditions have resulted in water transfers from agricultural to urban uses. Several studies have shown that these transfers have significant secondary economic impacts associated with the removal of irrigated land from production. In response, new methods of sharing water are being developed to allow water transfers that benefit both farm and urban economies, compared with previous permanent transfers that negatively impacted surrounding farm communities. One such project currently under development is the Arkansas Valley “Super Ditch,” which is a rotational crop fallowing plan based on long‐term water leasing designed to provide an annual supply of 25,000 acre‐feet of water (31.6 Mm3). This article analyzes the net benefits of implementing the “Super Ditch” for both the farmers and the surrounding community.  相似文献   
640.
Abstract: More than 85% of NO3? losses from watersheds in the northeastern United States are exported during winter months (October 1 to May 30). Interannual variability in NO3? loads to individual streams is closely related to interannual climatic variations, particularly during the winter. The objective of our study was to understand how climatic and hydrogeological factors influence NO3? dynamics in small watersheds during the winter. Physical parameters including snow depth, soil temperature, stream discharge, and water table elevation were monitored during the 2007‐2008 winter in two small catchments in the Adirondack Mountains, New York State. Snowpack persisted from mid‐December to mid‐April, insulating soils such that only two isolated instances of soil frost were observed during the study period. NO3? export during a mid‐winter rain‐on‐snowmelt event comprised between 8 and 16% of the total stream NO3? load for the four‐month winter study period. This can be compared with the NO3? exported during the final spring melt, which comprised between 38 and 45% of the total four‐month winter NO3? load. Our findings indicate that minor melt events were detectable with changes in soil temperature, streamflow, groundwater level, and snow depth. But, based on loading, these events were relatively minor contributors to winter NO3? loss. A warmer climate and fluctuating snowpack may result in more major mid‐winter melt events and greater NO3? export to surface waters.  相似文献   
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