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301.
The project focuses on the efficiency of combined technologies to reduce the release of micropollutants and bacteria into surface waters via sewage treatment plants of different size and via stormwater overflow basins of different types. As a model river in a highly populated catchment area, the river Schussen and, as a control, the river Argen, two tributaries of Lake Constance, Southern Germany, are under investigation in this project. The efficiency of the different cleaning technologies is monitored by a wide range of exposure and effect analyses including chemical and microbiological techniques as well as effect studies ranging from molecules to communities.  相似文献   
302.
Agri-environmental measures are payments to farmers to reduce environmental risks or to preserve cultivated landscapes. These measures are codified in European Union regulations. Poor spatial targeting is one of the major causes of low cost-effectiveness in agri-environmental measures. Existing studies on spatial targeting focus primarily on selected individual measures; hence, they do not allow for conclusions at the program level, where the planning and implementing of decisions on a number of different measures has to be made. In this study, we analyzed the impacts of two spatial targeting options (targeting of erosion-reducing measures on erosion vulnerable areas; targeting of grassland extensification on N-pollution vulnerable areas) on the cost-effectiveness of the single measures and the entire agri-environmental program of the federal state of Brandenburg in Germany. The methodological steps included an analysis of empirical data on land use and program participation, an expert-based environmental impact assessment and a spatial allocation procedure based on linear programming. The environmental impact assessment delivered goal-specific index values for each measures-land parcel combination expressing the suitability of the measures for contributing to four regionally relevant program objectives. The cost-effectiveness of the measures and the program were calculated by putting budgetary costs in relation to the achieved environmental index sum. The calculated cost-effectiveness of the program in 2006 was 89.6% of the simulated optimal cost-effectiveness. The spatial targeting of erosion-reducing measures on erosion vulnerable areas caused an increase in the cost-effectiveness at the measures level and almost no changes at the program level. The spatial targeting of grassland extensification on N-pollution vulnerable areas, despite also improving the cost-effectiveness of this measure, had negative effects on the cost-effectiveness of the program.  相似文献   
303.
Protected Landscapes (PLs) are increasingly used in Norway to conserve cultural (human modified) landscapes. In many cases the maintenance of agricultural activities in PLs is required to preserve landscape character. Whilst research exists on land conservation policies in general, the particular effects of PL on management and adjustment of the farms involved have not received attention in the literature. We present results from a questionnaire sent to owners of agricultural land within PLs in Norway. Whilst landowners were divided upon the effects of PLs on farm management, the economic situation of the farm was little affected. Furthermore, changes in farm management after the establishment of a PL did not seem to have been driven by the establishment of the PLs per se. Most importantly, farm management changes were related to potential options to develop the farm and its land. A statistical model showed that PL-farms did not differ significantly from farms outside PL in the development of their land use or animal husbandry. Our findings thus indicate that the establishment of PL played a minor role as a driving force of changes in farm management and farm income.  相似文献   
304.
Intensive research on pharmaceuticals in the environment started about 15 years ago. Since then a vast amount of literature has been published. The input and presence of active pharmaceutical ingredients (APIs) and their fate in the environment were and is still of high interest. As it has been extensively demonstrated that the active compounds are present in the environment some of the research interest has moved from analysis of the compounds, which is still undertaken, to effect studies in the lab and in field trials. It has been found that environmental concentrations can cause effects in wildlife if proper tools are applied for effect assessment. The question of mixture toxicity has gained more and more attention. It has been learned that classical tests may underestimate effects and risks. Work has been done in the field of risk assessment and risk management. As for risk management strategies to eliminate pharmaceuticals from wastewater or from the effluent of sewage treatment plants have been proposed and investigated. A tremendous amount of literature can now be found describing technical management measures such as oxidative or photolytic effluent treatment, filtering techniques, and application of charcoal. It has been learned however, that each of these approaches has its specific shortcomings. Therefore, additional approaches such as including people handling and using the compounds, and focusing on the properties of the compounds (“green pharmacy”) came into focus. Accordingly, this review gives an overview of the present state of knowledge presenting typical results and lines of discussion. This review makes no claim to give a complete overview including the full detailed body of knowledge of pharmaceuticals in the environment. Rather, it addresses important and typical topics to stimulate discussion.  相似文献   
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A new modelling approach to urban sprawl dynamics is introduced which allows representing qualitative knowledge on relations between moving actor populations and properties of locations. The results of this Qualitative Attractiveness Migration (QuAM) Model are scenario-like sets of possible future developments of the urban system, much in contrast to quantitative forecasts gained by traditional modelling approaches. QuAM models allow for the interaction between internal dynamics and external influences. The application of the new approach is exemplified by the case of urban sprawl in Leipzig since 1990. It was possible to reproduce the observed qualitative development and to calculate future scenarios. The scenario runs project a new wave of middle class driven residential sprawl and suggest implications for sprawl reducing policy interventions.  相似文献   
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Phosphatisation of small, soft-bodied fossils in the Upper Cambrian of Sweden yielded rich faunal assemblages, mainly of arthropods, which have been isolated from the rock by etching techniques. The highly diverse fossils are uncompressed and constitute the best preserved material known from the Paleozoic era, exposing minute details such as fine bristles, pores of glands, and eyes. Agnostus clearly has biramous appendages and therefore, cannot be regarded as trilobite anymore. The Crustacea are the most widespread components of the phosphatised fauna. The representatives of a separate order of Ostracoda already have been studied in some detail. Other primordial crustaceans include nauplius stages and show a surprising diversity in specialisation. A similar occurrence in Upper Devonian from the Carnic Alps demonstrates that this mode of preservation is not restricted to a single environment, but also can be expected elsewhere.  相似文献   
310.
Fluid charged lipid vesicles loaded with an inositol hexaphosphate solution were used to transport this allosteric effector into human intact red blood cells. Rate and extent of uptake of the vesicles and of the effector by the red blood cells were measured as changes in the O2 half-saturation pressure and the 31P-NMR spectra of the intracellular inositol hexaphosphate-haemoglobin complex.  相似文献   
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