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251.
252.
R.D. Kreutzwiser R.B. Feagan 《Journal of the American Water Resources Association》1989,25(3):667-674
ABSTRACT: Managing the demand for municipal water supply has become a viable alternative or supplement to traditional supply management responses. Though senior governments in Canada are committed to the concept, there is a lack of knowledge concerning the level of use of the demand management concept and little promotion of water conservation. This paper assesses the extent of the use of this concept as it applies to municipal water supply across southern Ontario and examines factors that influence the variation in use of water conservation strategies. Information from 219 municipalities revealed that the concept is not in wide use in southern Ontario and that existing variation can be partially explained by the extent of problems experienced and the population size served by the municipal water supply system. Suggestions for increasing municipal use of the demand management concept are offered. 相似文献
253.
关于Ramsey模型及其改进的研究和启示 总被引:5,自引:0,他引:5
席平健 《中国人口.资源与环境》2005,15(4):52-56
缺水已经成为我国经济发展和社会进步的重要制约因素之一.而对水价的制定到对水资源的利用效率起科十分关键的作用。本文通过对Ramsey模型及其改进的研究.得出如下启示.即实行阶梯水价既有利于实现杜会福利的优化,也可以起到节约水资源的效果。由于阶梯水价机制的设计可以为制度安排、资本进入和市场运行提供更大的弹性空间.因此.本文的政策含义是:在实施阶梯水价的背景下.政府只需对基量水价按边际成本的定价原则来严格规制.从而有效提升水务市场的运行效率。上述举措的优点在于:由于基量水价被严格规制.消费者的基本用水福利可以得到满足;超过基本用水量的水价和再生水价的相对放松规制会鼓励社会资本进入水务行业.使行业运营效率得到提高;国有资本退出水务行业使得政府财政负担减轻,同时.由于放松规制.政府的规制成本也得以降低。最终城市水务行业可以真正做到可持续的发展。 相似文献
254.
A benthic in situ flume and a 1D biogeochemical sediment model to evaluate solute fluxes across the sediment–water interface have been developed.
The flume was successfully used to determine oxygen and nutrient fluxes at various locations of the Neckar River in Germany.
The experimental results were linked with vertical pore water concentration profiles and independently verified with the model.
By combining experimental and model results we assessed the influence of dissolved oxygen concentrations in the water column
and the availability of degradable organic matter on sediment oxygen demand. The results and the derived relations can be
used to parameterize the sediment module of large scale water quality models, allowing one to assess the influence of sediment–water
interactions on various aspects of river water quality. Moreover, the biogeochemical sediment model can help to improve the
general understanding of the processes governing solute concentrations and fluxes in sediments and across their interfaces. 相似文献
255.
我国工业企业安全科技需求问题的探讨 总被引:2,自引:1,他引:2
宋马俊 《中国安全生产科学技术》2006,2(6):98-100
安全生产是一个庞大的系统工程,安全科学研究工作是这个庞大系统工程中的重要链条之一。安全科学研究工作的深度和广度对安全生产具有重大促进作用。围绕我国安全生产面临的实际问题,搞好重大安全科学研究课题的论证和列项,是争取快出成果和培养有用人才的一个不可忽视的问题. 相似文献
256.
Steve H. Hanke Lennart de Mare 《Journal of the American Water Resources Association》1982,18(4):621-626
Shortcoming associated with past water demand studies are evaluated. To overcome these shortcomings, pooled, time series, cross section data from -6, Sweden, are used in an ordinary Least squares analysis to estimate the demand for residential water. Elasticities for five variables, including price and income, are estimated. An approach for the conduct of future water demand studies is suggested. 相似文献
257.
Edwin D. Bailey 《Journal of the American Water Resources Association》1979,15(3):801-811
ABSTRACT: The Tucson area is totally dependent on ground water, which is in increasingly short supply due to excessive overdrafts. Tucson area waste water treatment plants discharge material quantities of secondary effluent downstream, which is lost to evapotranspiration and recharge of the ground water basin. The city and the four large mining companies who share the common Santa Cruz basin ground water, recognized the common water supply problem and agreed to fund a feasibility study for mining process use of the effluent to partly alleviate the overdraft of ground water. The study analyzed the projected waste water effluent resources, potential mining company demand for waste water effluent and possible interface of an effluent delivery facility with the proposed Central Arizona Project. The effluent resources were analyzed with respect to potential demand. An optimum alignment was selected. An optimum system was detailed through design schematics, amortized cost and finance requirements, and an implementation schedule. It was concluded that a waste water effluent delivery facility could be implemented which would utilize reclaimed effluent in quantities approximating 35 percent of basin overdraft and which would provide revenue for full cost recovery over a 20 year operation period. The mining companies are studying the internal economic impacts of the project. 相似文献
258.
ABSTRACT: The income and proce elasticity of demand for domestic water is estimated for Penang Island, Malaysia. A cross-sectional analysis of a random sample of 1400 households indicated an income-elasticity of zero for low-income families (per capita income less than US$300) and an elasticity of 0.2-0.4 for higher-income families. A time-series analysis of a subsample of individuals of varying income levels suggests a short-run price elasticity of -0.1 to -0.2. The implications of these results for demand forecasting are discussed. 相似文献
259.
In this paper, we explore how scenarios of future water withdrawals in a river basin are influenced by scale-dependent quantifications of the driving forces for two global-scale storylines. Either global-scale information or region-specific information is used to do the quantifications. In addition, we analyze the impact of including or not some restricted regional-scale information in the employed water use model. To develop scenarios of water withdrawals in the German part of the Elbe River basin, we applied the modules for domestic, thermoelectric power and manufacturing water use of the global water model WaterGAP, using scale-dependent driving forces scenarios and other scale-dependent model input. In the global-scale quantitative interpretations of the storylines of the IPCC SRES scenarios A1 and B2, all major driving forces of water withdrawals in the basin—population, thermoelectric power production and industrial gross domestic product—show vigorous increases between 2000 and 2025, while from the regional perspective, smaller increases but mostly decreases appear to be plausible. These discrepancies are partly due to the fact that for the global-scale interpretations only the historic developments until 1990 were taken into account, and not until 2000 as in the regional case. The resulting scenarios of sectoral water withdrawals in 2025 differ strongly between the two scale-dependent interpretations of the storylines, with the global one leading to much higher absolute water withdrawals and much lower withdrawal decreases between 2000 and 2025. Therefore, for regional assessments of water withdrawals, we recommend to embed the scenario analysis in global-scale storylines by performing regional-scale quantifications of the global qualitative driving forces scenarios, based on a limited amount of region-specific information. 相似文献
260.
石油短缺与中国经济安全 总被引:6,自引:0,他引:6
石油短缺已经成为引起中国能源危机最核心的问题,本文分析了中国石油短缺的背景及其影响因素,在实证分析的基础上,提出了“对石油依赖程度”这一概念。本文还把石油短缺与经济安全问题联系了起来,并提出了确保我国经济安全的具体对策。 相似文献