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911.
对遵义市1996-2001年TSP和FD为代表的尘污染情况进行了比较分析,结果显示TSP与FD之间缺乏相关性,同时确立了减少工业区排放控制TSP,加强局地扬尘管理控制FD的遵义市尘污染的防治思路,并依此提出了系列防治对策。 相似文献
912.
国内给水厂常规工艺改造的必要性和措施 总被引:1,自引:0,他引:1
针对目前城市给水厂水质现状与存在问题进行讨论,分析现有常规工艺改造的主要措施,阐明我国给水厂常规工艺改造的必要性。 相似文献
913.
914.
Shui-Ping Chang Ching-Gung Wen 《Journal of the American Water Resources Association》1997,33(2):343-357
ABSTRACT: Water quality and trophic conditions in the Feitsui Reservoir, a subtropical reservoir, were evaluated with data from a ten-year data base to depict the impacts of river impoundment upon the chemical and biological characteristics of a reservoir, and to discuss the effects of flushing rate on in-lake phosphorus concentrations and phytoplankton growth. The results of the investigation showed that during the incipient impounding period, the water quality in the Feitsui Reservoir was significantly affected by internal loadings from submerged vegetation and soil in the flooded area. Studies of the changes in phosphorus compounds indicated that total phosphorus concentration appeared to approach equilibrium after the seventh year of impoundment and that orthophosphate stabilized after the sixth year of impoundment. Concentrations of both phosphorus forms varied seasonally after attaining stability. Nitrogen compounds (NH3-N, NO3-N and NO2-N) approached equilibrium within three years after impoundment. The seasonal variation in carbon was correlated to the number of phytoplankton. The mean value of the N:P mass ratio has remained over 110 since year seven of impoundment (1990), indicating that phosphorus constitutes the potential limiting nutrient in the growth of phytoplankton. The rapid flushing rate (132.11 and 110.43 yr-1) in Feitsui Reservoir during the first and second impounding stages was a critical factor influencing the phytoplankton growth response to available nutrients. 相似文献
915.
916.
917.
研究了聚酯化纤废水中有机污染物乙醛、乙酸、乙二醇含量与COD之间的相关性,确定了COD与上述特征污染物含量的比值,并测定了它们的氧化率,为企业的生产工艺管理和 保管理提供了基础数据。 相似文献
918.
Clifford A. Siegfried 《Journal of the American Water Resources Association》1982,18(4):613-620
Phosphorus loading from precipitation and more than a dozen tributaries of Big Beat Lake, Woman, was determined for the period from January to December 1978. Direct precipitation contributed 1120 kg·P·yr-1 (0.096 g P·m-2·yr-1) while tributary runoff contributed 21,560 kg for a total P loading of 1.84 g P·m-2 Rathbone creek, although accounting for only 4 percent of the hydro-logic input to Big Bear Lake, contributed >27 percent of the annual phosphorus load. Phosphorus loading increased with increased impervious geology and increased development. Nitrogen loading exhibited similar loading patterns. Big Beat Lake is currently eutrophic and is likely to remain eutrophic. Calculations based on Vollenweider's critical phosphorus loading concept indicated that tributary P-loading would have to be reduced by >95 percent to achieve mesotrophic conditions. The completion of Big Bear Dam created a “naturally” eutrophic re mix which dl require proper management to enhance its resource potential. 相似文献
919.
Paul H. Whitfield 《Journal of the American Water Resources Association》1982,18(2):203-210
ABSTRACT: Four simple methods for estimating mass transport are evaluated in terms of the assumptions made about the properties of the data set being analyzed. The basic difference between the four methods considered are their assumptions regarding the manner in which concentration is distributed and the relationship between concentration and discharge. The most precise estimates of mass transport into and out of Schwatka Lake, Yukon Territory, were obtained from the model which assumes that concentration is log normally distributed and independent of discharge. 相似文献
920.
Robert C. Ostry 《Journal of the American Water Resources Association》1982,18(1):99-104
ABSTRACT: The Grand and Saugeen Rivers in southern Ontario were chosen for study as pilot watersheds under the Pollution From Land Use Activities Reference Group (PLUARG) study. The pilot watersheds have adjacent headwater areas and are physically similar in geology, physiography, and climate. Significant differences in water quality between the watersheds at their outlets are attributed to land use and population differences. The major pollutant sources in the two pilot watersheds were identified as trace elements from urban runoff and point source discharges; phosphorus from agricultural and urban runoff and private waste disposal; chloride from transportation corridors; and sediment and nitrogen from agricultural runoff. Yields at the watershed outlets were similar for suspended sediment and two to three times as high in the Grand River for phosphours, nitrogen, chloride, and lead. The higher phosphorus and nitrogen levels were attributed to larger point source inputs and the higher proportion of agricultural activity, comprising 75 percent of the Grand River basin compared to 64 percent in the Saugeen River basin. Similarly, the higher chloride and lead levels were attributed to an order of magnitude larger population and three times as much urban land in the Grand River basin compared to the Saugeen River basin. 相似文献