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991.
John B. Whitcomb 《Journal of the American Water Resources Association》1991,27(5):761-767
ABSTRACT: The water reductions resulting from Contra Costa Water District's 1989 residential audit program are measured using a multivariate regression model. The model explains metered residential water use as a function of both conservation and other household variables. The principle conclusions drawn are that (1) installation of low-flow showerheads reduced indoor water use by 9.7 percent or 7.8 gallons per capita day, (2) the outdoor segment of the audit reduced irrigation needs by 18.7 percent, and (3) irrigation timers are being used inefficiently. 相似文献
992.
Jerry W. Knapp F. Larry Leistritz 《Journal of the American Water Resources Association》1978,14(3):613-628
ABSTRACT: This paper reports on the development of a mathematical model for forecasting energy development in the Yellowstone study area for the years 1985 and 2000, and determining the associated economic demands for water, land, labor, capital, and mineral resources. The study was prepared for use by the Missouri River Basin Commission in conducting a comprehensive, “Level B” planning study of the water and related land resources in the Yellowstone River Basin. The study results indicate that the amount of coal development in the Yellowstone study area will depend primarily upon state and federal energy policies and regulations. Policies related to slurry pipeline transportation of coal will be particularly important in determining the level and pattern of future energy development in the area. Coal production under the “most probable” scenario is expected to increase from about 40 million tons in 1976 to 163 million tons per year by 1985, and 513 million tons in the year 2000. Consumptive water use for energy development in the study area could be as much as 556,000 acre-feet per year by the year 2000 (under the high scenario). A parametric analysis was conducted on the 1985 most probably scenario to determine the influence on the study results of variations in the delivered price of water. Water requirements were reduced by nearly one-fourth as water costs increased from zero to over $750 per acre-foot. 相似文献
993.
Gary D. Lynne William G. Luppold Clyde Kiker 《Journal of the American Water Resources Association》1978,14(3):719-729
ABSTRACT: Pricing policy in water allocation has become of more concern as some areas find water is indeed a scarce resource. Demand estimates, where the quantity purchased-value in use relationships are of concern, have been made in other studies for residential, industrial, and agricultural uses in many areas of the country. The price-quantity relations for water use in commercial firms are estimated and discussed for several different types of stores in this study. A derived demand model is used to estimate commercial demand in the Miami, Florida, area. The price elasticity was generally low (inelastic) for all groups studied except for department stores. This group was found to have an elastic demand for water at all prices above $0.93 per thousand gallons purchased per month, where the mean price for this part of the sample was $1.24. The major implication of the study is that commercial establishments may be responsive to price changes over the long run, much as has already been shown for other types of user groups in other studies. 相似文献
994.
Bill Macaitis Stanley J. Povilaitis Edward B. Cameron 《Journal of the American Water Resources Association》1977,13(4):795-806
ABSTRACT: By United States Supreme Court action, the diversion of water from Lake Michigan and the Lake Michigan Drainage Basin in the Metropolitan Chicago Area is regulated at an annual maximum rate of 3,200 cfs. Approximately 1,700 cfs of this diversion is used for water supply, and the remaining 1,500 cfs consists primarily of stormwater runoff with lesser amounts of direct lake diversion, such as lockage and leakage, navigational makeup water flows, and discretionary diversion needed to maintain water quality standards in the Metropolitan Sanitary District of Greater Chicago's basic waterways. In order to assess the schedule of its discretionary diversion needs, the District, using a computer model of its basic waterway system, has calculated the minimum discretionary diversion requirements for projected water quality conditions as successive elements of the District's water pollution control program are completed. The results of these analyses can be used as a basis for developing plans for future allocations of the limited supply of Lake Michigan water to other uses such as domestic water supply, when and if such supplies become available. 相似文献
995.
W. Douglas Morgan 《Journal of the American Water Resources Association》1980,16(5):941-945
ABSTRACT: This report places the engineering estimates of water conservation made by Sonnen and Evenson into the supply demand form used by most economists. Clarification is made concerning evaluation of conservation elasticities. 相似文献
996.
Deborah Ulinski Potter Michael P. Stevens Judy L. Meyer 《Journal of the American Water Resources Association》1982,18(4):627-633
ABSTRACT: Information on biologically important physical and chemical variables is presented for Lake Oconee, a newly impounded pumped storage reservoir in Georgia. During its first summer, when no pumping occurred, temperature, oxygen, pH, inorganic nitrogen, and phosphorus were vertically stratified with severe hypolimnetic oxygen depletion. During the second summer, when pumped storage was in operation, more homogenous vertical profiles, generally higher oxygen, and lower dissolved nutrient concentrations were observed. These pumped storage effects were observed at all stations, rather than being confined to the immediate vicinity of the dam. 相似文献
997.
David W. Hendricks Brian A. Janonis Steven Gerlek Joseph C. Goldbach James L. Patterson 《Journal of the American Water Resources Association》1982,18(2):279-288
ABSTRACT: The application of a water balance model in finding “solutions” to the supply/demand problem was demonstrated using the South Platte River basin as a case study. Solutions were ascertained by hand, using both “average” and “stress” supply/demand conditions, and were developed for 1980, 2000, and 2020; nonquantifiable boundary conditions were incorporated by judgement. The solution obtained for a particular set of conditions is not unique and has strong normative characteristics; thus it must be judged by various interest groups having different ethical positions. The water balance model has a tabular display format and so the “model” is merely a simple table, i.e., a “water balance table.” In this work the water balance table was displayed on an eight-foot by eight-foot color-coded magnetic board. The board provides a means to both find and display the needed supply/demand “solution.” The tabular display facilitates understanding of the systemwide solution and the formulation of value judgments. Based upon these value judgments and an initial “straw man” solution, successive negotiated solutions can be found which can minimize “conflict.” 相似文献
998.
Jerald L. Schnoor E. Gus Fruh 《Journal of the American Water Resources Association》1979,15(2):506-518
ABSTRACT: A vertical dissolved oxygen model was calibrated and verified using independent field data sets from 1972 and 1973 in Lake Lyndon B. Johnson (LBJ), a short detention time reservoir with anaerobic hypolimnion. Ammonia, carbonaceous BOD, conductivity, and temperature were also simulated as state variables. The conductivity results provided a check on the mass balance and the method of entering the inflows to the reservoir model. Emphasis was placed on calculating the sinks of dissolved oxygen in the hypolimnion which could be useful in management decisions. 相似文献
999.
Sandor C. Csallany James C. Neill 《Journal of the American Water Resources Association》1972,8(1):77-86
The purpose of this study was to determine the degree of influence of various factors on municipal water consumption in Illinois. For the collection of basic data, questionnaires were sent to all public water works of incorporated towns. The questionnaire was designed to obtain information on factors which may have any effect on water use. The effects of the different parameters on water consumption were based on several correlation and regression combinations of predictands and predictors. It was found that in the Chicago region the percent of services and water used for commercial and industrial purposes and the age of the water works were the most important parameters influencing water consumption (gallons per capita per day) when pumpage is metered at the water works as well as at the customers. For the State, excluding the Chicago region, percent of public water use, persons per service, population and commercial and industrial water use were the most important parameters. It has been recommended that similar statistical analysis be conducted periodically to establish a trend or law of change from the influencing parameters. 相似文献
1000.
Stable isotope (18O–H2O, 2H–H2O 34S–SO4
2-) andhydrochemical data (SO4
2-, Fe-concentrations) have beenused to estimate the annual groundwater inflow and outflow of mining lake ML 111 and to calculate the total amount of dissolvedsulfate and iron that is carried into the lake by groundwater. The hydrological balance suggests an annual groundwater inflow of 23 700 m3 and an annual groundwater outflow of 15 700 m3. The calculation of the sulfur and iron balances yielded an annual sulfate input of 37 800 kg and an annual iron input of 7000 kg with the groundwater inflow. Furthermore it was shown that significant fluxes of these elements go into the lake sediments which results in continuous release of acidity in the lake water. 相似文献