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841.
Michael I. Muiga George W. Reid 《Journal of the American Water Resources Association》1979,15(3):838-852
ABSTRACT: Mathematical modeling techniques are used to develop predictive equations for cost of water and waste water treatment processes in developing countries utilizing socioeconomic, environmental, and technological indicators. Predictive equations are developed for each of the three regions (Africa, Asia, and Latin America) for construction, operation, and maintenance costs of slow sand filter, rapid sand filter, stabilization lagoon, aerated lagoon, activated sludge, and trickling filter. Data analysis indicated that cost of water treatment processes is a function of technological indicator (percentage of imported materials), population, and the design capacity. The variables which gave the best correlation for waste water treatment cost were population, design flow, and the percentage of imported waste water disposal materials. 相似文献
842.
Abdel-Aziz I. Kashef Mahmoud M. Safar 《Journal of the American Water Resources Association》1975,11(4):651-664
ABSTRACT: The fresh-salt water interface in artesian aquifers has been investigated by various techniques on the basis of its analogy to the free surface in earth dams or cores of dams. Although various approximations are used, some more or less exact solutions exist. One of the simple methods, that would appeal to practical workers, was developed by the analysis of hydraulic forces. However, this method has not been checked thoroughly due to the lack of wide ranges of coverage by the more or less exact solutions. In this paper a suggested finite element method is used for the purpose of comparing with the method of hydraulic forces. The presented procedure eliminates some of the difficulties and uncertainties in current finite element procedures. Both methods proved to be in close agreement. Moreover, the hydraulic heads along the upper boundary of the artesian aquifer were found to be in close agreement with Dupuit's equation. The results of this investigation would greatly simplify the more complex management problems when the effects of discharge and/or recharge wells are added to the natural flow effects. 相似文献
843.
Emil Attanasi 《Journal of the American Water Resources Association》1975,11(1):69-76
ABSTRACT: Regional development and industrialization patterns are investigated and related via regression analysis to water resource investments for the island of Puerto Rico. Although results of this study indicate such investments have little immediate or short-term impact, significant relationships and variations in regional responses appear over longer time periods. This is shown by applying a variation of Zellner's method of performing seemingly unrelated regressions jointly. By this method, subsets of parameter coefficients of specific economic variables were restricted across regional equations while unrestricted coefficients were interpreted as explaining systematic regional variations in response to public investment. Regional differences, obtained by using this method, are frequently neglected when simply examining the overall development process. Among the more interesting results in terms of policy implications is the apparent significant relationship, over the period considered, between changes in the distribution of income and the pattern of water resource development. 相似文献
844.
Anthony Donigian W. Henry Waggy 《Journal of the American Water Resources Association》1974,10(2):229-244
ABSTRACT: Proper economic evaluation of alternative plans will maximize the utility achieved from the resources available for water resource management. A knowledge of the frequency of occurrence of the events under study is necessary to fully utilize the advantages of economic evaluation in planning. Frequency information is widely used in flood control and water supply, but relatively unknown in water quality planning. A continuous, dynamic hydrologic and water quality model is presented to develop frequency curves for various water quality criteria. Results from the Denver Regional Water Quality Management Study are discussed as an example of the use of frequency analysis for economic evaluation of water quality management. 相似文献
845.
C. W. Slaughter T. G. Freeman G. L. Audsley 《Journal of the American Water Resources Association》1974,10(4):802-812
ABSTRACT: Alaska possesses a diversity and magnitude of water resources unmatched in any other state. With over 15% of the area of the whole United States, and 40% of the nation's total fresh water supply, but an extreme lack of basic hydrologic and climatologic data, cooperation among agencies and individuals concerned with evaluating, planning, and carrying out water resources programs is essential. Toward this end, the Inter-Agency Technical Committee for Alaska (IATCA) was established under charter from the Water Resources Council. Representation in IATCA includes virtually all Federal, State, and academic entities in Alaska having an interest in the water resources of the State. Existence of IATCA has permitted or facilitated numerous Alaskan water resources programs. Several are described briefly in this paper: A flood warning network in the Chena River basin; establishment of the Caribou-Poker Creeks Research Watershed in Central Alaska; preparation and periodic updating of the “Ten-Year Plan for Water Resources Data Acquisition”; current planning for an integrated “real-time reporting network” for hydrometeorological data within the State; and a framework for implementation of the Alaskan phase of the National Water Resources Assessment, currently in the initial phases. Accomplishments to date testify that it is indeed possible to “get it all together” in the broad field of “Water Resources” in the largest of our 50 states. 相似文献
846.
Application of harmonic analysis to daily mean air, water temperature records for a location indicates that the first harmonic accounts for a major portion of the total variance in the records. Water temperature residuals are well correlated with air temperature residuals. Parametric values of the mathematical model for predicting water temperatures from air temperature records are stable from year to year. The air-water temperature relationship appears to be a stationary linear process. Consequently, it is possible to predict water temperatures at a location from the ambient temperature records provided both air and water temperature records are available for another similarly situated water body. 相似文献
847.
T. V. Mussivand 《Journal of the American Water Resources Association》1972,8(4):685-696
ABSTRACT. The task of resource management, in this case water resources, is rapidly becoming more complex, particularly because decision making is often contingent upon various prior activities and sets of data. Comprehensive planning is required in order to prevent misallocation of resources or mismanagement in resource development. Such planning involves five general phases which are applicable to any problem faced by society: (1) problem identification; (2) formulation of alternatives; (3) evaluation of alternatives; (4) implementation; (5) review. There have been many attempts to simplify the planning process and effectively carry out these five phases. The experience of the Alberta Water Resources Division has been that the Critical Path Method is one of the most useful tools available today for planning. It involves two basic steps: (1) preparation of a network diagram which (a) identifies all the activities necessary for the completion of a project, (b) correctly sequences these activities, (c) allocates resources; and (2) mathematical computations for scheduling the activities. In other words, this approach breaks a task down into smaller units or activities for easier organization, scheduling, and performance for eventual completion of the project. This paper will illustrate the effectiveness of the Critical Path Method by discussing its application to actual water resources projects. 相似文献
848.
Sie Ling Chiang 《Journal of the American Water Resources Association》1971,7(1):171-174
ABSTRACT. High percentage of imperviousness in the city is the source of storm runoff. Roof area contributes significantly to the imperviousness. An attempt to make use of roofs as urban flood control device and water conservation measure is advocated. Two different schemes, one for built-up industrial-commercial area, the other for residential area, are suggested. The former utilizes the roof as detention reservoir for flood control, the latter employs recharge pit to convert runoff into ground water resource. The proposed schemes are not only hydrologically, hydraulically and structurally sound but also economically feasible. It is worth considering in the future planning of urban renewal and urban development. 相似文献
849.
Robert R. Criss 《Journal of the American Water Resources Association》1971,7(4):639-643
ABSTRACT The growing social consciousness and concern with human well-being has resulted in numerous water resource use and control programs, the results of which must be measured not in the customary monetary terms, but rather in terms of social and human welfare. Interdisciplinary research offers the greatest promise of yielding fruitful results in establishing planning methodology that would result in a maximum utilization of funds available for water resource programs. Working with the various social science disciplines, accountants have begun research in social measurement thus opening the door to a new field of accountancy known as socio-economic accounting. The development of social accounting systems will improve water resource management by projecting heretofore unmeasureable social values into the management decision making process. 相似文献
850.
Bobby E. Price 《Journal of the American Water Resources Association》1971,7(4):676-683
ABSTRACT .A summary is presented of remarks made at a conference held at Louisiana Tech University on the possibility of diverting some of the Mississippi River water to Texas and New Mexico. The Texas Water Plan which has initiated the diversion possibility is discussed and particular reference is made to the activities of the federal and state agencies directly responsible for determining various aspects of the diversion study. These agencies include the Texas Water Development Board, Texas Water Quality Board, Louisiana Department of Public Works, State Engineer's Office of New Mexico, Mississippi River Commission, and the Bureau of Reclamation. 相似文献