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This paper examines the problem of asymmetric information in financial markets due to a lack of essential environmental information. The literature indicates that asymmetric information generates various problems for the actors of financial markets such as incomplete information for investment decisions and lending procedures, misallocation of financial market funds, the underestimating of stock price securities, and poor environmental risk management choices. To this end, this paper develops a game-theoretic approach to examine both the persistent nature of asymmetric information caused by the absence of accurate environmental information and to indicate how a well-organized, trustworthy, internationally agreed auditing accounting certification scheme could play a critical role in limiting the magnitude of this problem.  相似文献   
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Detailed knowledge of the quantity and composition of urban emissions is a prerequisite for successful application of atmospheric models to predict transport and distribution of primary and secondary air pollutants in the troposphere. We investigate the prospects and limitations of aircraft measurements in the determination of emission fluxes from urban areas. Our analysis focuses on data collected in September 1994 in and around Athens, Greece. Generally, emission fluxes from cities can be quantified with aircraft and with the minimum acceptable precision (uncertainty better than a factor of 2) only under very favorable meteorological conditions, namely in a homogeneous flow field in a well-mixed boundary layer. Better accuracy can be achieved only through ensemble averaging of repeated measurements. From our measurements in the Athens area, we deduced relative emission ratios of pollutant gases. With the support of ground-based measurements in a street canyon, the emission ratios NOx/CO, SO2/CO, and volatile organic compounds/CO (34 individual VOCs) could be determined with high precision. These results are very useful in analyzing differences between various existing emission inventories. Our data for VOCs reveal that the non-traffic emissions are of the same magnitude as the emissions originating from traffic.  相似文献   
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This paper is the second part of a research programme concerning the modelling capabilities of accidental releases of heavier-than-air toxic gases. The existing theory, which includes the strength of the source and the subsequent development of the released cloud under representative environmental conditions, is described. Comparison of the ZZB-2 system predictions with field data from the Desert Tortoise and Lyme Bay V, ammonia and chlorine releases, shows excellent agreement at distances between ≈ 200 m and a few kilometres from the source. The correlation between observed and predicted cloud concentrations, was in all cases significant at a confidence level better than 95%.  相似文献   
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A multi-criteria approach was applied for the disposal into the sea of ~1 100 000 m3 of sediment, dredged from a coastal area in the northeastern part of the Thermaikos Gulf. This sediment (classified as muddy) is distributed vertically into two distinct Layers (A and B) with the thickness of the surficial sedimentary unit ranging from 7 to 54 cm. Its geochemistry reveals increased Cr and Ni concentrations, which may be attributed to natural enrichment through the erosion of the adjacent igneous and metamorphic rocks. In addition, a low to moderate contamination from urban-originated heavy metals, like Cu, Pb and Zn as well as from aliphatic and polycyclic hydrocarbons was identified for the upper Layer A. However, the limited proportion (5.5%) of the polluted Layer A in the total volume of the dredged material could not affect the good quality (assessed by the Sediment Quality Guidelines) of the bulk sediment. The identification of the optimum marine dumping site was based on (a) the physicochemical similarity (detected by the application of a cluster analysis) of the dredged material with the surficial deposits of potential dumping sites in the Outer Thermaikos Gulf, and (b) the consideration, based on previous studies, of various criteria related to the disposal area such as deep-water circulation, influence on living resources, impact on economical (aquaculture, fishing, navigation), recreational (fishing) and military activities.  相似文献   
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The statistical distinctness in assessing differences of the trophic status between sampling sites was investigated in the present study. Nutrient (phosphate, nitrate, nitrite, ammonia) and phytoplankton (chlorophyll, cell number) variables from nine sampling stations were used for the validation of the statistical procedures. Raw data, transformed data, and simulated data derived on normalized nutrient–phytoplankton frequency distribution were tested. The Kruskal–Wallis (KW) nonparametric statistical procedure was also applied on the raw data as well as the analysis of variance on transformed and simulated data. In all cases, pairwise comparisons for each parameter between stations were performed. The results showed that maximum distinctness between sampling sites for all the six variables was attained using the simulated data. The KW method showed the poorest discrimination between stations. The methodology of producing and using simulated data is described step by step, and the advantages in cases of unequal sampling design or small sample size are discussed.  相似文献   
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