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981.
Existing studies on the economic impact of wildfire smoke have focused on single fire events or entire seasons without considering the marginal effect of daily fire progression on downwind communities. Neither approach allows for an examination of the impact of even the most basic fire attributes, such as distance and fuel type, on air quality and health outcomes. Improved knowledge of these effects can provide important guidance for efficient wildfire management strategies. This study aims to bridge this gap using detailed information on 24 large-scale wildfires that sent smoke plumes to the Reno/Sparks area of Northern Nevada over a 4-year period. We relate the daily acreage burned by these fires to daily data on air pollutants and local hospital admissions. Using information on medical expenses, we compute the per-acre health cost of wildfires of different attributes. We find that patient counts can be causally linked to fires as far as 200–300 miles from the impact area. As expected, the marginal impact per acre burned generally diminishes with distance and for fires with lighter fuel loads. Our results also highlight the importance of allowing for temporal lags between fire occurrence and pollutant levels.  相似文献   
982.
We study the introduction of new technologies when their costs are subject to idiosyncratic uncertainty and can only be fully learned through individual experience. We set up a dynamic model of clean experience goods that replace old polluting consumption options and show how optimal regulation evolves over time. In our base setting where social and private learning incentives coincide, the optimal tax on the polluting consumption is increasing over time. We show, however, that if social and private learning incentives diverge because the private discount rate exceeds the social discount rate, it may be optimal to temporarily increase the tax rate beyond net marginal external damages to induce more learning before reducing the tax rate to the steady state level. Alternatively, one could complement the tax with subsidies for first-time users which can be phased out over time. Similar results apply if consumers have biased expectations. We therefore give a rationale for introductory subsidies on new, clean technologies and non-monotonic tax paths from a perspective of consumer learning.  相似文献   
983.
The ability to store excess intermittent renewable electricity is increasingly being seen as a key option for integrating large quantities of renewable capacity. However, intermittent energy sources currently account for very small amounts of total generation. Despite this fact, policymakers have begun implementing requirements that will dramatically increase the amount of bulk storage capacity. This paper examines the social benefits provided by bulk storage in the Texas electricity market, which has a large amount of renewable capacity relative to other states, but still quite limited renewable penetration. We focus on the impact of arbitraging electricity across time—a major service of bulk storage. Using current storage technologies, we demonstrate that electricity arbitrage will increase daily CO2 emissions by an average of 0.19 tons for each MWh stored. In addition, daily SO2 emissions will increase by an average of 1.89 pounds/MWh while NOX emissions will fall by an average of 0.15 pounds/MWh.  相似文献   
984.
In connection with the change in economic principles and disintegration of big industrial enterprises, the environmental pollution in Baltic States decreased considerably in 1991-1996. Although there are still many things waiting to be done, the improvement of the Baltic environmental situation during the years of independence gives us a cause to be optimistic.  相似文献   
985.
This overview summarises the present knowledge on major sources of pollution, which are of concern for the Mediterranean Sea. Eutrophication, red tides, organic loads, hydrocarbon spills, heavy metal contamination and their biological effects are described on the light of the ecological characteristics of the Mediterranean. In particular special attention is paid to the "new pollution" processes; i.e. , the introduction of novel substances with biological activity that might have synergetic effects with "classical pollutants". Different compartments and marine ecosystems are considered and compared. The degree of anthropogenic impact and its apparent trends are discussed. Possible monitoring plans and remedial actions for a sustainable management of coastal zones subjected to increasing pollution are also suggested.  相似文献   
986.
As part of a pollution monitoring study, oysters (Crassostrea gasar) were sampled in June 1996, in order to determine the concentrations and distribution of chlorinated hydrocarbons in two stations (near Boulay Island and Riviera Golf) of the Ebrie Lagoon, in the Abidjan area.

The chromatographic analysis of the oven dried samples revealed the presence of PCBs (2.13 to 86.22 ppb or ng/g dry weight), DDE (<0.48 to 169.55 ppb), DDD (<1.04 to 60.27 ppb), DDT (1.43 to 77.81 ppb, lindane (<0.22 to 91.64 ppb), aldrin (<0.30 to 154.1 ppb), endrin (<0.23 to 293.31 ppb) and dieldrin (<0.26 to 199.74 ppb). the results indicated high concentrations in oysters sampled near Boulay Island, due to industrial, agricultural and port activities going on in this area.

Compared to DDD/ΣDDT and DDT/ΣDDT, the DDE/ΣDDT ratios were high indicating old DDT inputs. the ΣDDT/PCBs ratios were higher than 1 illustrated the predominance of organochlorine inputs from agriculture activities. the presence of lindane in both stations illustrated the problem of fishing with toxic products.

Negative correlations found between dry tissue weight and organochlorine compounds concentrations showed that young oysters may concentrate more of these substances. More studies are needed in order to make any conclusions on their bioaccumulation trends.  相似文献   
987.
US EPA Models-3 system is used for calculating the exchange of ozone pollution between three countries in southeast Europe. For the purpose, three domains with resolution 90, 30 and 10 km are chosen in such a way that the most inner domain with dimensions 90 × 147 points covers entirely Romania, Bulgaria and Greece.The ozone pollution levels are studied on the base of three indexes given in the EU Ozone Directive, mainly accumulated over threshold of 40 ppb for crops (AOT40C, period May–July), number of days with 8-h running average over 60 ppb (NOD60) and averaged daily maximum (ADM). These parameters are calculated for every scenario and the influence of each country emissions on the pollution of the region is estimated and commented.Oxidized and reduced sulphur and nitrogen loads over the territories of the three countries are also determined. The application of all scenarios gave the possibility to estimate the contribution of every country to the S and N pollution of the others and detailed blame matrixes to be build.Comparison of the ozone levels model estimates with data from the EMEP monitoring stations is made.  相似文献   
988.
To aid air quality model development and assess air quality forecasts, the Meteorological Development Laboratory (MDL) provided categorical verification metrics for developmental aerosol predictions. The National Air Quality Forecasting Capability (NAQFC) generated 48 h (of) gridded hourly developmental predictions for the lower 48 states (CONUS) domain in 12 km horizontal spacing. The NAQFC uses the North American Mesoscale (NAM) model with EPA’s Community Multiscale Air Quality (CMAQ) model to produce predictions of ground level aerosol concentrations. We used bilinear interpolation to calculate predicted daily maximum values at the location of the observation sites. We compared these interpolated predicted values to the observed daily maximum to produce 2 × 2 contingency tables, with a threshold of 40 μg/m3 during the months of March–August, 2007. The model showed some degree of skill in predicting aerosol exceedances. These results are preliminary as the NAQFC model for aerosol prediction is in the developmental stage. A more comprehensive performance evaluation will be accomplished in 2008, when more data become available. Our verification metrics included categorical analyses for Fraction Correct (FC) or percent correct (FC × 100), Threat Score (TS) or Critical Success Index (CSI), Probability of Detection (POD), and the False Alarm Rate (FAR), Mean Absolute Error (MAE) and mean algebraic error or bias, where bias is forecast minus observation. Graphic products included weekly statistics for the CONUS displayed in the form of bar charts, scatterplots, and graphs. In addition, we split the CONUS into six geographic regions and provided regional statistics on a monthly basis. MDL produced spatial maps of daily 1-h maximum predicted aerosol values overlaid with the corresponding point observations. MDL also provided spatial maps of the daily maximum of the 24-h running average. We derived the 24-h running average from the 1-h average predicted aerosol values and observations.  相似文献   
989.
Carbon leakage is of interest in both academic and policy debates about the effectiveness of unilateral climate policy, especially in Europe, where the EU Emissions Trading System (EU ETS) affects many traded sectors. We review how the literature identifies leakage and the pollution haven effect. We then evaluate whether EU ETS emission costs caused carbon leakage in European manufacturing, using trade flows in embodied carbon and value from the Global Trade Analysis Project (GTAP). We find no evidence that the EU ETS caused carbon leakage.  相似文献   
990.
We use a residential sorting model incorporating migration disutility to recover the implicit value of clean air in China. The model is estimated using China Population Census Data along with PM2.5 satellite data. Our study provides new evidence on the willingness to pay for air quality improvements in developing countries and is the first application of an equilibrium sorting model to the valuation of non-market amenities in China. We employ two instrumental variables based on coal-fired electricity generation and wind direction to address the endogeneity of local air pollution. Results suggest important differences between the residential sorting model and a conventional hedonic model, highlighting the role of moving costs and the discreteness of the choice set. Our sorting results indicate that the economic value of air quality improvement associated with a one-unit decline in PM2.5 concentration is up to $8.83 billion for all Chinese households in 2005.  相似文献   
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