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991.
Energy efficiency plays an important role in reducing the carbon externality from buildings, but economic analyses of more efficient, green building have thus far ignored input costs. This paper finds that the average marginal cost of green-labeled construction projects is smaller than the value premiums documented in the literature. However, design fees, representing just a fraction of development costs but paid largely up-front, are significantly higher for green construction projects. These projects also take longer to complete. The results provide some insight into the market barriers and market failures that may explain the relatively slow adoption of otherwise economically rational green construction practices.  相似文献   
992.
Analyses of policies to reduce gasoline consumption have focused on two effects, a compositional effect on the fuel economy of the automotive fleet and a utilization effect on how much people drive. However, the literature has missed a third effect: a matching effect, in which policies change how high-utilization households are matched to fuel-efficient vehicles in equilibrium. We show that higher gas prices should lead to stronger assortative matching. Empirical estimates using US micro-level data are consistent with this hypothesis. We find a $0.50 increase in the gas tax would reduce US gas consumption by 0.8% through the matching effect alone, bringing annual environmental benefits of about $1.7 billion.  相似文献   
993.
Home buyout programs facilitate the permanent relocation of residents away from areas considered to be at risk from future hazards, though few studies have examined the impacts of home buyout programs on affected households and communities beyond the program implementation period. In this paper, we examine between-neighborhood variation in key recovery indicators for three neighborhoods that followed different paths to recovery after Hurricane Sandy: one that rebuilt in situ, one that participated in a buyout and relocated, and one located immediately adjacent to the buyout zone. Three years post-disaster, buyout participants are faring worse in terms of place attachment and social capital compared to residents in the other two neighborhoods, while the neighborhood adjacent to the buyout zone is also showing signs of decline. These findings suggest that the social costs of buyouts extend well into the recovery period, and that the place-based ties and social networks that would typically help individuals cope with disaster impacts and persevere through adversity may be diminished for buyout participants, ultimately hindering their recovery. We conclude with a discussion of the implications of buyouts on participating and affected communities, as well as implications for research and policy.  相似文献   
994.
提出了现有电除尘器可采用余热利用节能、高频电源、双区结构、隔离振打等新技术进行提效节能改造的思路,分析了这些新技术的技术特性,并进行了实际案例剖析,对满足《火电厂大气污染物排放标准》(GB13223-2011)烟尘排放的要求,形成现有电除尘器的新型改造模式具有重要参考价值。  相似文献   
995.
从炭黑废水中提取的炭黑,经干燥,其质量可符合导电炭黑的要求。重点介绍了提取导电炭黑过程中物料的传递及干燥工艺,并对试车中出现的问题进行了分析。  相似文献   
996.
An evaluation of the economic and environmental costs and benefits that would result if the Zorinsky Federal Building, located in Omaha, Nebraska, USA, converted its current lighting system to a more energy-efficient system (i.e., joined the EPA's Green Lights Program) was conducted. Lighting accounts for 20–25 percent of all electricity sold in the United States. Costs considered in the study included the cost of retrofitting the building's existing lighting system and the cost of disposal of the current lamps and ballast fixtures. Benefits included a reduction of electric utility costs and a reduction of emissions of SO2, NO x , CO2, and CO from electric utility power plants. Environmental and health issues for air pollutant emissions were also addressed. The results showed that significant reductions in utility bills as well as reductions in air emissions would result from a major building converting to a more energy efficient lighting system. The results showed that conversion of this large building would reduce SO2 emissions by 14.6 tons/yr and NO x emissions by 6.3 tons/yr. In addition, the conversion would reduce annual energy costs by approximately $114,000.  相似文献   
997.
海上溢油回收技术研究   总被引:4,自引:0,他引:4  
论述了厌氧-好氧(A/O)工艺的基本原理及工艺参数。该工艺在冀东油田两座废水处理站的应用结果表明,对废水中石油类物质、COD、硫化物去除效果明显。高一联合站及柳一联合站污水经处理后,石油类物质去除率分别为90.6%和96.0%;COD去除率分别为86.0%和91.6%;硫化物去除率分别为94.8%和98.2%,处理后的污水均达到一级排放标准。另外,采用厌氧-好氧工艺的成本相对较低,处理费用低于0.5元/m3。处理后的污水若回注地下,平均费用为4.7元/m3。  相似文献   
998.
含油污泥处理工艺研究进展   总被引:13,自引:2,他引:13  
产生于污水处理过程中的含油污泥,其含水率很高并不易沉降而难于处理,对生产与环境保护构成了极大的危害。介绍了对浓缩干化、浮选除油、降粘压滤及萃取分离等方法的研究情况,着重介绍了以“气浮-萃取-压滤”为主体的草取分离处理工艺,该工艺不但可以消除含油污泥对环境的污染危害,还可以回收污泥中的污油,为其它有机物含量高的污泥处理提供了可借鉴之路。  相似文献   
999.
含钴镍废水的萃取处理研究   总被引:7,自引:0,他引:7  
杨智宽 《化工环保》1996,16(4):195-198
采用N235作萃取剂,在合适的酸度和氯离子浓度条件下,对含钴镍废水进行溶剂萃取处理,重点研究了酸度、氯离子浓度、萃取级数及反萃条件对钴镍分离效率的影响,试验结果表明,可以有效地回收利用废水中的钴和镍。  相似文献   
1000.
No energy technology is risk free when all aspects of its utilization are taken into account. Every energy technology has some attendant direct and indirect health and safety concerns. Solar technologies examined in this paper are wind, ocean thermal energy gradients, passive, photovoltaic, satellite power systems, low- and high-temperature collectors, and central power stations, as well as tidal power. For many of these technologies, insufficient historical data are available from which to assess the health risks and environmental impacts. However, their similarities to other projects make certain predictions possible. For example, anticipated problems in worker safety in constructing ocean thermal energy conversion systems will be similar to those associated with other large-scale construction projects, like deep-sea oil drilling platforms. Occupational hazards associated with photovoltaic plant operation would be those associated with normal electricity generation, although for workers involved in the actual production of photovoltaic materials, there is some concern for the toxic effects of the materials used, including silicon, cadmium, and gallium arsenide.Satellite power systems have several unique risks. These include the effects of long-term space travel for construction workers, effects on the ozone layer and the attendant risk of skin cancer in the general public, and the as-yet-undetermined effects of long-term, low-level microwave exposure. Hazards may arise from three sources in solar heating and cooling systems: water contamination from corrosion inhibitors, heat transfer fluids, and bactericides; collector over-heating, fires, and out-gassing and handling and disposal of system fluids and wastes. Similar concerns exist for solar thermal power systems. Even passive solar systems may increase indoor exposure levels to various air pollutants and toxic substances, eitherdirectly from the solar system itself or indirectly by trapping released pollutants from furnishings, building materials, and indoor combustion.Operated by Union Carbide Corporation under contract W-7405-eng-26 for the U.S. Department of Energy.  相似文献   
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