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611.
H. E. Jeffries K. G. Sexton 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1087-1089
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R. Ryan Dupont Joan E. McLean Richard H. Hoff William M. Moore 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1257-1265
Laboratory evaluation of the efficacy of soil phase photodegradation of recalcitrant hazardous organic components of wood treating wastes is described. The photodecomposition of anthracene, biphenyl, 9H-carbazole, m-cresol, dibenzofuran, fluorene, pentachlorophenol, phenanthrene, pyrene and quinoline under UV and visible light was monitored over a 50-day reaction period in three test soils. Methylene blue, riboflavin, hydrogen peroxide, peat moss and diethylamine soil amendments were evaluated as to their effect on the enhancement of compound photoreaction rates in the test soil systems. Dark control samples monitored over the entire study period were utilized to quantify non-photo mediated reaction losses. Compounds losses in both the dark control and irradiated samples were found to follow first order kinetics, allowing the calculation of first order photodegradation reaction rate constants for each test soil/compound combination. Degradation due to photochemical activity was observed for all test compounds, with compound photolytic half-lives ranging from 7 to approximately 180 days. None of the soil amendments were found to improve soil phase photodegradation, although photosensitization by anthracene was shown to significantly enhance the rate of photodegradation of the other test compounds. Soil type, and its characteristic of internal reflectance, proved to be the most significant factor affecting compound degradation rates suggesting the necessity for site specific assessments of soil phase photodegradation potential. 相似文献
614.
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616.
J.D. Hamilton K.H. Reinert J.V. Hagan W.V. Lord 《Journal of the Air & Waste Management Association (1995)》2013,63(4):247-251
Abstract Synthetic polymers reach municipal landfills as components of products such as waste household paints, packaging films, storage containers, carpet fibers, and absorbent sanitary products. Some polymers in consumer products that reach landfills are designed to photodegrade or biodegrade. This article examines the significance of degradable polymers in management of solid waste in municipal landfills. Most landfills are not designed to photodegrade or biodegrade solid waste. Landfill disposal of stable polymers such as polyacrylics and polyethylenes is not associated with significant polymer degradation or mobility. Stability to photodegradation and biodegradation is an advantage when municipal landfills are used for disposal of polymer products as solid waste. Use of landfill disposal can be a responsible means to manage polymer waste and can be part of an overall waste management plan which includes source reduction, recycling, reuse, composting, and waste-to-energy incineration. 相似文献
617.
Helen H. Suh George A. Allen Petros Koutrakis Robert M. Burton 《Journal of the Air & Waste Management Association (1995)》2013,63(6):442-452
Abstract Acidic sulfate concentrations were measured in metropolitan Philadelphia during the summers of 1992 and 1993, as part of a continuing effort to characterize particle concentrations in urban environments. Sampling was performed simultaneously at eight sites located within and around metropolitan Philadelphia. Sites were selected based on their population density and on their distance and direction from the city center. Air pollution sampling was conducted every other day during the summer of 1992 and every day during the summer of 1993. All samples were collected for 24-h periods beginning at 9 a.m. (EDT). All acidic sulfate and ammonia samples were collected using modified Harvard-EPA Annular Denuder Systems (HEADS). In this paper, we examine the spatial variation in acidic sulfate and ammonia concentrations within the metropolitan Philadelphia area. We also identify factors that may influence their variation and develop models to predict their concentrations. Outdoor sulfate (SO4 2?) concentrations were uniform within metropolitan Philadelphia; however, aerosol strong acidity (H+) concentrations varied spatially. This variation generally was independent of wind direction, but was related to local factors, such as the NH3 concentration, population density, and distance from the center of the city. Physico-chemical models, which were developed using data collected during the summer of 1992, were excellent predictors of 24-h and mean summertime H+ concentrations measured during the summer of 1993. Models accounted for 78% of the variation in 24-h H+ levels. Results suggest that a single stationary ambient (SAM) monitor would be sufficient to estimate SO4 2? exposures for populations living in Philadelphia. For H+, however, multiple monitoring sites or models should be used to determine the outdoor H+ exposures of populations living in urban environments, although a single SAM site may provide an excellent index of H+ variation over time. 相似文献
618.
Abstract Daily atmospheric concentrations of sulfate collected at six locations in the northeastern United States are regressed against meteorological factors, ozone, seasonal cycles, and time in order to determine if a significant trend in sulfate can be detected. The data used in this analysis were collected during the Sulfate Regional Experiment (SURE, 1977-1978) and the Eulerian Model Evaluation Field Study (EMEFS, 1988-1989). Ozone, specific humidity, and seasonal terms (reflecting the potential of the atmosphere for oxidation of sulfur dioxide) emerged as important explanatory variables. After accounting for the variability explained by environmental factors, the median estimated change in sulfate concentration from the six locations over the 11-year period is -22% (or -28% if ozone is not used as an explanatory variable). Although there are wide variations among locations, these changes are commensurate with an estimated 25% decline in sulfur emissions in the northeastern U.S. during the same period. These analyses provide insight into methods for detecting reductions in sulfate that may be expected to occur as a result of the Clean Air Act Amendments of 1990. Uncertainties in the estimates, with consideration of serial correlation in the data, imply a minimum detectable reduction of 10% using this modeling procedure with similar data availability. 相似文献
619.
D. R. van der Vaart W. M. Vatavuk A. H. Wehe 《Journal of the Air & Waste Management Association (1995)》2013,63(4):497-501
In an earlier paper, major commercially available incinerator technologies designed to treat dilute waste gas streams containing volatile organic compounds (VOCs) were described in a qualitative comparison. In addition, a simplified procedure was outlined through which important sizing parameters could be calculated given certain information about the waste gas. This paper describes the use of these parameters in developing a study (±30percent) cost estimate for the total capital investment and the total annual costs incurred in treating a waste stream of volatile organic compounds (VOCs). An illustrative problem used in the former paper is completed here in order to contrast some of the economic differences between thermal and catalytic incinerator systems. 相似文献
620.