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951.
William P. Blacutt-Mercado 《Natural resources forum》1993,17(3):207-215
This paper examines the General Environmental Law of Bolivia which was recently passed by its Congress. It is a multi-purpose law with two primary objectives: (i) the protection and conservation of the environment; and (ii) the promotion of sustainable development. In this law, environmental benefits are emphasized by stating general principles, not by attempting to define the means. Regulations setting forth the means are left to the writing of subsequent complementary codes. This paper shows that much of the controversy surrounding the legislation disappears when it is seen as a guideline rather than an operational part of Bolivia's industrial policy. In essence, the law addresses environmental awareness in a region that is more anxious than ever to speed economic growth. 相似文献
952.
Small-and large-scale farm operators and applicators urgently need user-friendly and cost-effective on-site methods to treat dilute-formulated herbicide-laden wastewater (i.e., rinsate). In this study, we investigated solvent-regenerable synthetic adsorbents, Ambersorb® 563 adsorbent, Ambersorb 572 adsorbent, and Ambersorb 575 adsorbent, as alternatives to activated carbon (Filtrasorb ® 400) for cleanup of water containing Dual 8E (a.i., metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide]) or Banvel 4L (a.i., dicamba [3,6-dichloro-2-methoxybenzoic acid]). Batch-type adsorption experiments were conducted to compare adsorptive capacities of the various adsorbents. Adsorption maxima, obtained from adsorption isotherms, indicated that of the Ambersorb adsorbents tested, Ambersorb 572 adsorbent generally exhibited the highest adsorptive capacities for the herbicides tested and was comparable to Filtrasorb 400. Solvent (methanol) regenerability studies demonstrated that herbicide was readily recovered from Ambersorb 572 adsorbent and Filtrasorb 400. In general, metolachlor was more readily recoverable than dicamba. In fixed-bed column studies, Ambersorb 572 adsorbent exhibited twice the adsorptive capacity of Filtrasorb 400. Fixed-bed columns were more effective in removing metolachlor from herbicide containing water regardless of the adsorbent used. Multicycling of Ambersorb 572 adsorbent resulted in 30% loss of adsorptive capacity for dicamba as Banvel 4L and no loss of adsorptive capacity for metolachlor as Dual 8E. Working capacity was reached after three adsorption-regeneration cycles. Fixed-bed columns packed with solvent-regenerable adsorbents may prove useful as part of an on-site wastewater disposal system. 相似文献
953.
James P. Pastorick 《补救:环境净化治理成本、技术与工艺杂志》1993,3(2):221-231
To date, most of the development of unexploded ordnance (UXO)-related requirements and procedures have been accomplished by the U.S. Army Corps of Engineers and the U.S. Army Toxic and Hazardous Materials Agency. The U.S. Navy and U.S. Air Force also have a significant requirement for environmentally related UXO expertise. This article traces the evolution of the UXO field, as developed by small businesses and the various branches of the U.S. Army, and describes the implications of conducting an environmental investigation or remediation in an area contaminated, or suspected to be contaminated, with UXO. Lastly, the basic procedures and the tools and equipment used to accomplish UXO decontamination are described to inform field managers of the impact that UXO hazards can have on their overall project. 相似文献
954.
955.
956.
E T. Foster T. C. Chen J. P. Newton E. O. Isu 《Journal of the American Water Resources Association》1972,8(5):863-870
ABSTRACT. Theoretical and practical results are summarized for a study to determine optimal water resource allocation in a proposed water conservancy district. The area of this district, which covers several river basins, contains a large number of existing and proposed facilities such as reservoirs and diversions. The operation of all of these facilities was to be determined along with the sizing of the proposed facilities in order to optimize given objective functions. Related efforts in optimal river basin utilization were surveyed, and linear programming was selected as an expedient optimization technique. The problem is formulated by identifying time stages which together constitute a repetitive cycle such as a year. With these stages, it is possible to associate operational and capacity variables with network components, which are branches and nodes. Objective functions are assembled for the component variables. Constraint equations are written in terms of the variables to reflect network nodal continuity, capacity restrictions, and adjudications such as water rights. A numerical example is considered in which the existing and proposed facilities are aggregated to produce a small, tractable number of facilities. This paper examines the example results and suggests future improvements for models of this type. 相似文献
957.
ABSTRACT. The water resources manager, concerned with providing for citizen needs for water in all its varied aspects, is obliged to consider the public interest in his decision making. But the public interest, although inferring the superiority of public over purely private interests, is more of a concept of political ethics than an operational objective. Recent attacks on water resources developments place in question just how responsive the water resources manager has been to the public at large during the planning process. The recent broadening of planning objectives beyond economic efficiency to include greater attention to social goals is an encouraging development. Efforts should be expanded toward greater citizen participation and more attention should be given to sampling surveys to determine citizen attitudes on water resources proposals. In the last analysis, the decision-making process must combine the expertise of the water resources manager and the participation of the people through the political process. 相似文献
958.
Donald S. P. Puccini 《Journal of the American Water Resources Association》1971,7(6):1144-1152
The recent world-wide trend towards centralization of all environmental management functions into one regulatory agency has illustrated the necessity for resources management agencies to adopt a total systems viewpoint. Environmental systems are typically complex and multi-dimensional in nature. Mathematical models for the management of air, water and land resources have found wide acceptance among planners and decision-makers. Ecological models of life processes have not reached the same state of development or acceptance. A general review of ecological systems theory and examples of the types of ecological models that have been developed to date arc presented in this paper. With this material as a background and given the vast literature on engineering and economic models, a conceptual framework for an approach to environmental studies and the analysis of polluted environmental systems is presented. 相似文献
959.
Peter P. Zwack Mark D. Shulman John W. Philpot 《Journal of the American Water Resources Association》1969,5(4):9-15
A 30-year record of monthly precipitation for Northern New Jersey was analyzed for its statistical components. With a weak annual periodicity eliminated, the series was found to be random. The data for each month were fit with a gamma distribution using Thom's suggested best estimates of the distribution parameters. A one-thousand-year simulated monthly precipitation series was generated using random values from the twelve gamma distributions. The statistical properties of the simulated and sample time series agreed well. Numerous anomalous precipitation regimes were observed in the simulated data. 相似文献
960.
Roy Burke James P. Heaney Edwin E. Pyatt 《Journal of the American Water Resources Association》1973,9(3):433-447
ABSTRACT The problem of water resources management can be viewed as one requiring the existence and application of some type of “collective decision” mechanism. Currently, the general water resource decision problem is solved using an “individual decision” format without explicit consideration of the dominant social decision system. This paper demonstrates the need for blending technical planning activities with organized societal processes and then proposes a specific public decision framework to satisfy this requirement. The key element in this planning framework is a generalized “bargaining arena” which serves to link technical activities with the social system. Using this bargaining device we can (1) specify policy at a local level, (2) incorporate “social decision” rules into the planning process, and (3) provide local access to the decision process. A simple case of regional water quality management is used to describe the application of this planning procedure and to offer encouragement for successful use in more complex real-world cases. 相似文献