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341.
In the current study, the potential of forest-based biomass supply for the pellet production in Nepal is investigated. This study showed that about 2.76 million tonnes (Mt) biomass in the form of pellets are potentially available from forest-based biomass. Considering a processing capacity of 6 tonnes (t)/hr of a pellet plant, the production cost of the pellets was calculated to be $43.53/t. Pellets are generally used as fuel to produce thermal energy in industries, which helps to save the economy and the environment of the country.  相似文献   
342.
The exemption for groundwater wells for residential uses from the prior appropriations system, common in the western United States, has eroded in Washington State since about 2000 due to a series of legal cases. Water markets can allow the transfer of an existing water right, typically from an agricultural use, to compensate for the effect of a new residential well. But water must be legally and physically available in a way suitable to satisfy mitigation requirements. A recent court case in the Skagit basin in Northwestern Washington State has effectively halted residential development in rural areas of the basin because no suitable water rights are available to purchase for mitigation. This paper presents and examines the cost‐effectiveness of various water supply mitigation strategies. We find a small‐scale, distributed stream‐side storage system for augmenting instream flow purchased from downstream sources is relatively cost‐effective to mitigate against the effects of domestic groundwater use compared to more common alternatives. We consider transporting water to storage sites by both small‐gauge pipe and by truck. Overall, trucking water to stream‐side storage and release points tends to be more cost‐effective to mitigate against indoor‐use only given current subbasin housing densities, whereas piping for direct streamflow augmentation is more cost‐effective for higher mitigation needs associated with indoor and outdoor use and higher housing densities.  相似文献   
343.
基于DEA方法的耕地利用效率分析   总被引:21,自引:0,他引:21  
引入了数据包络分析(DEA)测度1997~2004年我国耕地利用效率,该方法可以使用多项投入和多项产出指标,弥补了当前对耕地利用效率测度只考虑单项投入和产出指标的不足;并将耕地利用效率分解为纯技术效率和规模效率以剖析耕地生产效率变化的源泉;最后利用计量经济模型分析了影响耕地利用效率变化的因素。研究结果表明:1997~2004年我国耕地利用效率存在着一定的波动性,平均综合技术效率为0732,耕地利用效率整体不高;从综合技术效率的构成来看,综合技术效率的变化趋势和纯技术效率基本一致,这表明耕地利用效率的变化主要是由纯技术效率的变化引起的;同时各个行政区间的耕地利用效率也存在着很大的差异;影响耕地利用效率的因素很多,按照影响程度从大到小排序是:耕地资源禀赋、经济发展水平、自然条件、农业生产条件。  相似文献   
344.
A model describing parents’ preferences to relieve their own and their children's acute illnesses is estimated using stated-preference data. Estimated marginal rates of substitution (MRS) between child and parent illness are about two, indicating that parents value children's illness attributes twice as highly as their own. The MRS is larger for younger children, falls toward unity as the child approaches adulthood, and appears to reflect parental altruism rather than parent–child differences in initial health or illness costs. Intra-family allocations may compensate for chronic health impairments. Parents’ willingness to pay to avoid own or child illness increases with income, declines with fertility, increases at a decreasing rate with duration and number of symptoms, and depends on perceived discomfort and activity restrictions. Current methods of assessing morbidity benefits of environmental regulations may understate substantially the value of children's health, particularly in African-American families.  相似文献   
345.
本文把最优控制理论中的极大值原理引入环境经济系统分析中,通过实例计算,阐述了企业微观环境经济调控模型的建立过程及求解方法。  相似文献   
346.
In the arid regions of Tunisia, considerable investments are being made to maintain the old water harvesting techniques and introduce new ones to capture the scarce amount of rainwater (100 mm to 230 mm annually) for agricultural and domestic purposes. However, no detailed assessment of the multiple effects and the costs and benefits of these techniques have been made so far. This paper summarizes the results of an in depth investigation of the multiple impacts (runoff mobilization, ground water recharge, agro-socio-economic impacts) of the water harvesting works undertaken in the watershed of oued Oum Zessar (southeastern Tunisia). The importance of interdisciplinary and integrated approaches was revealed through this detailed impact assessment and economic evaluation. In fact, the profitability of the water harvesting works depends largely on the criteria chosen. However, further refinements are needed to better include all possible impacts (positive and negative) that occur as a result of the installation of the water harvesting structures.  相似文献   
347.
Firms would like to capitalize on consumers' willingness to pay more for goods that use environmentally friendly production techniques, but have difficulty credibly conveying their environmental friendliness. One possible remedy is “ecolabeling,” where a third party certifies firms' products. To model this phenomenon, I analyzed a market characterized by asymmetric information in which firms decide whether to seek an ecolabel. Market equilibrium is discussed in three settings: where both technologies and outputs are fixed (so the only choice is whether to seek certification), where technologies are fixed but outputs are not, and where firms can choose both technology and output.  相似文献   
348.
应用"污染贡献率"这一指标,分析了"三河三湖"流域COD和氨氮排放的重污染行业以及地区分布,指出了各流域COD和氨氮排放的控制重点.同时分析了各流域重污染行业的"经济贡献率",最后结合行业的污染贡献率和经济贡献率以及行业在地区所占的比例,提出了几点重要的结论.  相似文献   
349.
环保产业渗透性及价值体现   总被引:1,自引:0,他引:1  
文章分析了环保产业发展中的4个特点:全方位渗透、政策依赖、动态发展、高科技支撑及对相关产业的带动等特性。对环保产业渗透性及所体现的产值及价值进行了探讨,提出在环保产业产值统计中应补充渗透性所体现的产值贡献,并给出了一个评价模式:  相似文献   
350.
上海市全面实行排污许可证交易的可行性探讨   总被引:3,自引:0,他引:3  
排污许可证交易系统应建立在一个完善和有效的排污许可证管理体制基础上。文章认为上海市现有排污许可证体制的经济内涵、产权、初始分配方式、基价体系等方面必须进行改革和完善。与发达国家实行的排污许可证体制相比,上海市实行的排污许可证体制缺乏相应的经济内涵,只是排污许可“执照”体制,上海市的排污许可证交易实际上是排污许可“执照”交易。根据上海市现行排污许可证体制的经济内涵及实施现状来看,近期内全面推行真正意义上的排污许可证交易所必需的条件还未成熟。目前应当继续在黄浦江上游地区进行排污许可证交易,并在各方面进行探索,进一步积累经验。  相似文献   
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