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101.
    
Among all geological CO2 storage possibilities, deep saline aquifers are of great interest due to their worldwide repartition and their important storage volume. We present a workflow using available vintage data with poor 2D seismic coverage for building a first geological and reservoir model for CO2 geological storage in the deep saline aquifers of the St. Lawrence Platform in the Bécancour area (Québec, Canada). In order to optimize the sparse available geoinformation using a geostatistical method, we krige the tops of the geological formations recorded at 11 wells using surfaces modeled from seismic horizons picked on 99.4 line‐km of 2D seismic reflection data. Modeled geological horizons show a good compromise between the geometric structure expressed by the variograms and the interpreted variations evaluated from seismic horizons. Using available well logs, distribution of porosity and permeability are computed for generating multiple realizations of the petrophysical properties of the targeted aquifer by sequential Gaussian simulations. The scarcity of available petrophysical data in the targeted aquifer generates high variability between the different realizations. Due to this uncertainty, the population of the 3D geological model with petrophysical properties that are required for further geostatistical simulations of CO2 injection do not allow to achieve reliable results. The methodology presented in this paper shows the possibilities and limits of using vintage data, and provides evidence that geophysical data acquired in a 3D fashion are important to fully characterize a reservoir for CO2 geological storage. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd  相似文献   
102.
The aim of this study was to describe the impact of re-vegetation on the restoration of microbial community structure and soil microbiological properties in sand dunes that had been affected by mining activity. Soil samples were collected during the dry and rainy seasons from a chronosequence (1, 9, 21 years) of re-vegetated dunes using a single preserved dune as a reference. The composition of the fatty acid methyl esters and soil microbial properties were evaluated. The results showed that the changes in microbial community structure were related to seasonal variations: biomarkers of Gram-positive bacteria were higher than Gram-negative bacteria during the dry season, showing that this group of organisms is more tolerant to these stressful conditions. The microbial community structure in the natural dune was less affected by seasonal variation compared to the re-vegetated areas, whereas the opposite was observed for microbiological properties. Thus, in general, the proportion of saprobic fungi was higher in the natural dune, whereas Gram-negative bacteria were proportionally more common in the younger areas. Although over time the re-vegetation allows the recovery of the microbial community and the soil functions, these communities and functions are different from those found in the undisturbed areas.  相似文献   
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Journal of Material Cycles and Waste Management - A solid enriched with NaA zeolite was synthesized from a coal fly ash, and the so-obtained zeolitized material was used as ion exchanger for...  相似文献   
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Biogenic volatile organic compounds (BVOCs) are widely involved in a variety of atmospheric chemical processes due to their high reactivity and species diversity. To date, however, research on BVOCs in agroecosystems, particularly fruit trees, remains scarce despite their large cultivation area and economic interest. BVOC emissions from different organs (leaf or fruit) of apple and peach trees were investigated throughout the stages of fruit development (FS, fruit swelling; FC, fruit coloration; FM, fruit maturity; and FP, fruit postharvest) using a proton-transfer-reaction mass spectrometer. Results indicated that methanol was the most abundant compound emitted by the leaf (apple tree leaf 492.5 ± 47.9 ng/(g·hr), peach tree leaf 938.8 ±  154.5 ng/(g·hr)), followed by acetic acid and green leaf volatiles. Beside the above three compounds, acetaldehyde had an important contribution to the emissions from the fruit. Overall, the total BVOCs (sum of eight compounds studied in this paper) emitted by both leaf and fruit gradually decreased along the fruit development, although the effect was significant only for the leaf. The leaf (2020.8 ±  258.8 ng/(g·hr)) was a stronger BVOC emitter than the fruit (146.0 ± 45.7 ng/(g·hr)) (P = 0.006), and there were no significant differences in total BVOC emission rates between apple and peach trees. These findings contribute to our understanding on BVOC emissions from different plant organs and provide important insights into the variation of BVOC emissions across different fruit developmental stages.  相似文献   
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This paper describes a dynamic multistage game in which sustainability is a value that is shared between companies and stakeholders in a competitive market. The game solution could move from a Nash equilibrium to a higher equilibrium, the MES equilibrium, because of the presence of stakeholders who influence the choice and the set of sustainable strategies. Stakeholders provide feedback to companies (by way of awards, ratings, rankings, rebukes, etc.) at every stage of the game. Positive feedback gives a company the chance to expand its business opportunities, leveraging on good reputation, customer loyalty, operational risk mitigation, resilience, employees' cohesion, etc. The interaction between companies and stakeholders also allows companies to seize market opportunities (e.g., supplying sustainable products for responsible customers, sustainable investments for investors, etc.). The sustainability game demonstrates how sustainability can engage the economic system in a market shift.  相似文献   
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In the last decade, political pressure from international organisms has contributed to the divulgation and the adoption of social accountability practices. Using an inductive method, this research examines the state of the art of best social reporting practices carried out by Italian listed companies, by scoring and assessing the different maturity levels in application of the principles required by the main reporting models mentioned and by exploring the indicators disclosed in corporate social responsibility (CSR) reports. We analyze CSR reporting by Italian companies making up the FTSE ECPI Leaders Index of the Italian Stock Exchange. The findings show an overall good level of disclosure. The data confirm the results of previous studies as they highlight the escalation in sustainability reporting: both the quantity and quality of sustainability information are increasing. However, the results may raise doubts that companies consider CSR as a ‘fashion’. In fact, one of the criticisms levelled against CSR is that information is self‐gathered and self‐reported. More mandatory rules may improve transparency; however these may compromise the CSR concept, so it is necessary to further investigate the findings. Copyright © 2012 John Wiley & Sons, Ltd and ERP Environment.  相似文献   
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