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1.
The behaviour of the three organophosphate esters tributyl phosphate (TBP), tris(2-chloroethyl)phosphate (TCEP) and tris(2-butoxyethyl)phosphate (TBEP) during infiltration of river water to ground water has been investigated. The monitoring site is the Oder River and the adjacent Oderbruch aquifer. From March 2000 to July 2001, 76 ground water samples from monitoring wells located close to the Oder River and nine river water samples were collected. Additionally, influent and effluent samples from local waste water treatment plants, one sample of rain water and samples of roof runoff were collected. All samples were analysed by solid-phase-extraction followed by gas chromatography/mass spectrometry. TBP, TCEP and TBEP were detected at mean values of 622 ng l(-1), 352 ng l(-1), and 2955 ng l(-1), respectively in municipal waste water effluents. This points to a major input of these compounds into the Oder River by municipal waste water discharge. The concentrations of TBP and TBEP decreased downstream the Oder River possibly due to aerobic degradation. TBP, TCEP and TBEP were detected in ground water influenced predominantly by bank-filtered water. This demonstrates a transport of organic compounds by river water infiltration to ground water. TBP, TCEP and TBEP were also detected in rain water precipitation, roof runoff and ground water predominantly influenced by rain water infiltration. This hints to an input of these compounds to ground water by dry and wet deposition after atmospheric transport. Organophosphate esters were also detected in parts of the aquifer at 21 m depth. This demonstrates low anaerobic degradation rates of TBP, TCEP and TBEP.  相似文献   
2.
Book reviews     
Cost Benefit Analysis of Environmental Change

Per‐Olov Johansson

Cambridge, Cambridge University Press, 1993, 232 pp., £13.95

Computerised Environmental Modelling: A Practical Introduction using Excel

J. Hardisty, D. M. Taylor & S. E. Metcalfe

Chichester, Wiley, 1993, 204 pp., £14.95

Keeping Pace with Science and Engineering: Case Studies in Environmental Regulation

Washington DC, US National Academy of Engineering, 1993

World Without End: Economics, Environment and Sustainable Development

D. W. Pearce & J. J. Warford

Oxford University Press, New York, 1993, 440 pp., £35.95  相似文献   

3.
The soil fauna of ecofarmed and conventionally farmed fields and grasslands was investigated in various regions of Austria. The results obtained from the evaluation of a total of 13 paired sites are reviewed in this contribution: (1) many of the investigated soil zoological parameters do not differ statistically in ecofarmed and conventionally farmed fields and grasslands; (2) there are no striking differences in species composition and dominance structure of the protozoa, an important group of indicator organisms due to their delicate external membranes, their short generation time and their high contribution to energy flow and nutrient cycling; (3) all differences which can be guaranteed with an error probability of α = 10% or less invariably show higher biological activity in the ecofarmed plots. The soil physical and chemical investigations which accompanied the zoological studies on some sites indicate that the higher biological activity is caused by the higher humus content and the lower soil compaction. The organic matter content is significantly higher in the ecofarmed plots, whereas soil compaction is more pronounced under conventional cultivation; (4) conventional agriculture has a more detrimental effect on soil fauna in semi-arid regions without stockfarming than in atlantic regions with mixed husbandry. A short review of the literature shows our results to be consistent with those of other studies. It is increasingly evident that generalizations like ‘Conventional farming destroys life in the soil’ or ‘Ecofarming stimulates soil life’ are only partially supported by the available data. A far more comprehensive view taking into account especially climate, soil type and farm management is necessary. However, the discernible detrimental effects on the soil organisms caused by conventional farming call for serious consideration and ought to stimulate the development of soft agricultural technology and intensified soil biological research. Future research should include studies on productivity of soil animals under various management systems, the analysis of single factors (e.g. the special admixtures used in biodynamic farming) to elucidate causative mechanisms, and studies on the relationship between soil animals, crop production and sustained yield.  相似文献   
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Foraging desert ants, Cataglyphis fortis, encounter different sequences of visual landmarks while navigating by path integration. This paper explores the question whether the storage of landmark information depends on the context in which the landmarks are learned during an ant's foraging journey. Two experimental set-ups were designed in which the ants experienced an artificial landmark panorama that was placed either around the nest entrance (nest marks) or along the vector route leading straight towards the feeder (route marks). The two training paradigms resulted in pronounced differences in the storage characteristics of the acquired landmark information: memory traces of nest marks were much more robust against extinction and/or suppression than those of route marks. In functional terms, this result is in accord with the observation that desert ants encounter new route marks during every foraging run but always pass the same landmarks when approaching the nest entrance.  相似文献   
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New findings on the causes of waste and emissions, which were obtained from analysing numerous material streams in various sectors of industry, are presented in this article. It describes the implications of these findings for the vision of clean production, for formulating environmental policy concerning cleaner production targets, for the opportunities to assess to what extent the cleaner production targets have been met, and for the cleaner production assessment. A modified cleaner production assessment approach is presented, and illustrated using leather production as an example. The consequent implications for the diffusion of cleaner production are discussed.  相似文献   
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This paper presentse-SEREM (Smart Emission ReductionEstimation Manual), a cost-free, easilyaccessed and updated, web-based manual forestimating emission reductions from Joint Implementation (JI) andClean Development Mechanism (CDM) projects. e-SEREM's main functions arethe selection of a benchmark for a specificproject type in the power or heat sectorand the calculation of the annual andcumulative emission reductions accrued bythis project for its crediting lifetime.e-SEREM was developed in order to test itsapplicability and practicality in assistingproject developers and evaluators toelaborate baselines easily and calculatethe emission credits earned by candidate JIor CDM projects hosted in several countries.  相似文献   
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