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241.
Dennis F. Kahlbaum Jon M. Heuss George T. Wolff 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1070-1078
ABSTRACT Because the U. S. Environmental Protection Agency (EPA) has changed the National Ambient Air Quality Standards (NAAQS) for ambient particulate matter (PM), there is a great deal of interest in determining recent PM trends. This paper examines trends in PM10 (i.e., particulate matter less than 10 micrometers in diameter) for areas of the United States based on their attainment status—for PM10 and ozone nonattainment and attainment areas. The analysis also focuses on urban, suburban, and rural areas, and eastern and western areas. The time period of evaluation is from 1988 through 1995. To shed further light on the ambient PM10 trends, trends in ambient SO2, NO2, and volatile organic compounds (VOCs) are also analyzed. Finally, trends in emission inventories of SO2, NOx, VOCs, and PM10 are evaluated. Results of the analysis show that widespread and similar reductions in PM10 levels have occurred over the last seven years. Annual reductions range from 3.0% to 3.8%, with the greatest reductions coming in PM10 nonattainment areas, but with very significant reductions also in PM10 attainment areas, ozone attainment areas, and rural areas. The widespread reductions appear to be due to a set of controls or common factors that are having a fairly uniform effect in all of the areas. The consistency of the reductions in different areas suggests that the reductions may also be primarily in the fine particles (i.e., those less than 2.5 micrometers in diameter, or PM2.5), which are more readily transported than coarse particles. 相似文献
242.
Precipitation chemistry measurementsobtained by the Canadian Air and PrecipitationMonitoring Network (CAPMoN) and the U.S. NationalAtmospheric Deposition Program/National Trends Network(NADP/NTN) have been examined using more than 7 yrof collocated data from two sites, namely, Sutton,Quebec, Canada and State College, Pennsylvania, U.S.A.In the case of the CAPMoN data, weeklyprecipitation-weighted mean concentrations, totalsample depths and total standard gauge depths werecomputed from daily data and compared to thecorresponding weekly sampling data of the NADP/NTNnetwork. Seasonal and annual precipitation-weightedmean concentrations and deposition values were alsocomputed for both networks and compared. Statisticallysignificant between-network biases were found to existin the weekly results for most of the measuredvariables, particularly standard gauge depth, sampledepth, pH, H+, NO3
-,NH4
+,Na+; the NADP/NTN values were consistently lowerthan those of CAPMoN with the exception of pH andNa+. The magnitude of the biases was less than35% of the median CAPMoN weekly value for the 7 yr. For most of the measured parameters, thevariability of the between-network differencesrepresented less than 20% of the median CAPMoN weeklyvalue. Both the between-network biases andvariabilities were functions of several physicalparameters, the most dominant being the sample depthand the ionic concentration. For seasonal and annualdeposition values, statistically significantbetween-network biases were found for H+,SO4
2-, NO3
-,Ca2+,NH4
+ for both periods; for Mg2+ andK+ for seasonal data; and Cl- for yearlydata, with the NADP/NTN deposition values being lowerthan those of CAPMoN. The relative biases ranged from7 to 37%. Part of the between-network bias in thedeposition estimates was directly attributable to astrong bias in the standard gauge depths of the two networks. 相似文献
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Introduction
Currently, alcohol industry-sponsored advertisements subsume traditional designated driver and don't drink and drive messages within responsible drinking campaigns. Yet, to date, there remains a dearth of literature specifically examining the attitudinal beliefs impaired drivers attach to the responsible drinking message.Objective
This investigation sought to examine the responsible drinking attitudes and beliefs of impaired drivers, specifically examining their confidence and intention to drink responsibly the next time they consumed alcohol.Methods
A random sample of 729 students attending a large, public Texas university completed a web-based administration of the Characteristic of Responsible Drinking Survey (CHORDS).Results
Participants in this sample who had driven while impaired by alcohol exhibited significantly less confidence in refraining from drinking and driving and reported significantly lower intentions to designate a driver, take a taxi, or use a safe-ride program the next time they consumed alcohol. Additionally, they also reported less confidence, and lower intentions, to ensure their blood alcohol concentrations remained below the legal limit (0.08%) the next time they consumed alcohol.Conclusions
Drivers who had driven while impaired significantly differed in their confidence and intention to drink responsibly the next time they consumed alcohol. Logistic regression results indicate that by increasing one's confidence in responsible drinking, and increasing their intention to drink responsibly, the likelihood of impaired driving can be decreased.Impact on industry
Results from this investigation demonstrate one’s responsible drinking attitudinal beliefs accounts for a significant amount of the variance associated with one’s alcohol-related behaviors. Thus, further research should examine and establish how individuals conceptualize and practice responsible drinking. 相似文献246.
Dennis O’Grady 《Journal of the American Water Resources Association》2011,47(1):39-51
O’Grady, Dennis, 2011. Sociopolitical Conditions for Successful Water Quality Trading in the South Nation River Watershed, Ontario, Canada. Journal of the American Water Resources Association (JAWRA) 47(1):39‐51. DOI: 10.1111/j.1752‐1688.2010.00511.x Abstract: The South Nation River watershed has a regulated water quality trading program. Legally, wastewater dischargers must not discharge any increased loading of phosphorus (P) into receiving waters. New wastewater systems are now choosing trading instead of traditional P removal technology, and point source dischargers are buying P credits from rural landowners, primarily farmers. These credits are generated by constructing nonpoint source pollution control measures. Mathematical formulae are used to calculate the credits of P removed by each measure. A successful trading program requires several conditions, including community agreement, legislative backing, credit and cost certainty, simplified delivery and verification, written instruments, and legal liability protection. South Nation Conservation, a community‐based watershed organization, is the broker handling the transactions for these P credits. The program is run by a multi‐stakeholder committee, and all project field visits are done by farmers and not paid professionals. An independent evaluation showed higher opinions for the broker and regulatory agency, and most farmers were willing to, or had already, recommended the program to other farmers. 相似文献
247.
The relationship between agricultural intensification and biological control: experimental tests across Europe 总被引:2,自引:0,他引:2
Thies C Haenke S Scherber C Bengtsson J Bommarco R Clement LW Ceryngier P Dennis C Emmerson M Gagic V Hawro V Liira J Weisser WW Winqvist C Tscharntke T 《Ecological applications》2011,21(6):2187-2196
Agricultural intensification can affect biodiversity and related ecosystem services such as biological control, but large-scale experimental evidence is missing. We examined aphid pest populations in cereal fields under experimentally reduced densities of (1) ground-dwelling predators (-G), (2) vegetation-dwelling predators and parasitoids (-V), (3) a combination of (1) and (2) (-G-V), compared with open-fields (control), in contrasting landscapes with low vs. high levels of agricultural intensification (AI), and in five European regions. Aphid populations were 28%, 97%, and 199% higher in -G, -V, and -G-V treatments, respectively, compared to the open fields, indicating synergistic effects of both natural-enemy groups. Enhanced parasitoid: host and predator: prey ratios were related to reduced aphid population density and population growth. The relative importance of parasitoids and vegetation-dwelling predators greatly differed among European regions, and agricultural intensification affected biological control and aphid density only in some regions. This shows a changing role of species group identity in diverse enemy communities and a need to consider region-specific landscape management. 相似文献
248.
Apeti DA Lauenstein GG Christensen JD Johnson EW Mason A 《Environmental monitoring and assessment》2011,181(1-4):399-418
This study evaluated changes in oyster tissue contaminant levels following North Atlantic tropical cyclones to determine if changes in contaminant concentrations were predictable. The basis for this study was analysis of coastal chemical contaminant data from the National Oceanic and Atmospheric Administration's (NOAA) National Status and Trends Mussel Watch Program and NOAA's National Weather Service storm track data. The tendency for contaminant (metals and organic compounds) body burdens to increase or decrease in oyster tissue after a storm was assessed using contingency and correspondence analyses. Post-storm contaminant levels in oysters revealed a consistent pattern of distribution, which could be described as follows: (1) most of the organic contaminants stay within their long-term concentration ranges, (2) very few organic contaminants decreased, and (3) metals overwhelmingly tend to increase. 相似文献
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