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731.
732.
Corjan Brink Carolien Kroeze Zbigniew Klimont 《Atmospheric environment (Oxford, England : 1994)》2001,35(36):2618
Agriculture is an important source of NH3, which contributes to acidification and eutrophication, as well as emissions of the greenhouse gases CH4 and N2O. Because of their common sources, emission reduction measures for one of these gases may affect emissions of others. These interrelations are often ignored in policy making. This study presents an analysis of the effects of measures to reduce NH3 emissions on emissions of N2O and CH4 from agriculture in Europe. The analysis combines information from the NH3 module of the Regional Air pollution INformation and Simulation (RAINS) model for Europe with the IPCC method for national greenhouse gas inventories. The IPCC method for estimating agricultural emissions of N2O and CH4 is adjusted in order to use it in combination with the RAINS database for the European agricultural sector. As an example, we applied the adjusted method to the agricultural sector in the Netherlands and found that application of several NH3 abatement options may result in a substantial increase in N2O emissions while the effect on CH4 emissions is relatively small. In Part 2 of this paper we focus on the resulting emissions for all European countries for 1990 and 2010. 相似文献
733.
A land use database and examples of biogenic isoprene emission estimates for the state of Texas, USA
Christine Wiedinmyer Alex Guenther Mark Estes I. Wade Strange Greg Yarwood David T. Allen 《Atmospheric environment (Oxford, England : 1994)》2001,35(36):6465-6477
Using data from a variety of sources, land use and vegetation in Texas were mapped with a spatial resolution of approximately 1 km. Over 600 classifications were used to characterize the land use and land cover throughout the state and field surveys were performed to assign leaf biomass densities, by species, to the land cover classifications. The total leaf biomass densities associated with these land use classifications ranged from 0 to 556 g/m2, with the highest assigned total and oak leaf biomass densities located in central and eastern Texas. The land cover data were used as input to a biogenic emissions model, GLOBEIS2. Estimates of biogenic emissions of isoprene based on GLOBEIS2 and the new land cover data showed significant differences when compared to biogenic isoprene emissions estimated using previous land cover data and emission estimation procedures. For example, for one typical domain in eastern Texas, total daily isoprene emissions increased by 38% with the new modeling tools. These results may ultimately affect the way in which ozone and other photochemical pollutants are modeled and evaluated in the state of Texas. 相似文献
734.
K. Lebecki J.
li K. Cybulski Z. Dyduch 《Journal of Loss Prevention in the Process Industries》2001,14(6):489-494
The paper describes large-scale tests of triggered barriers of different design. Main stress was put on examining suitability of the flame detector developed in US Bureau of Mines to work as a trigger for the barriers. It was found that the detector works satisfactorily with the barriers of different design providing a suitable mean to suppress explosions in galleries, either in mines or in other industries. 相似文献
735.
The possibility of dust explosions by static electricity in a malt grain silo was investigated. Two kinds of experimental equipment were applied. One was to supply electrostatic charge in order to investigate the charge build up characteristics. The other was to transport the malt grain pneumatically in order to investigate the frictional charge accumulation in the transportation system.
The particle charge of the pulverized malt grain was in the order of 10−14 C. The particle charge of the malt grain was in the order of 10−9 C and the pipe charge in the transport system was also in the order of 10−9 C. The charge accumulated on both the pulverized particle and the grain particle were small in view of the incendiary potentiality. However, attention must be paid when the particles are dumped into isolated space. There might be a charge accumulation that will lead to the ignition of the dust cloud. 相似文献
736.
GHG (greenhouse gas) emission factors for waste management are increasingly used, but such factors are very scarce for developing countries. This paper shows how such factors have been developed for the recycling of glass, metals (Al and Fe), plastics and paper from municipal solid waste, as well as for the composting of garden refuse in South Africa. The emission factors developed for the different recyclables in the country show savings varying from ?290 kg CO2 e (glass) to ?19 111 kg CO2 e (metals – Al) per tonne of recyclable. They also show that there is variability, with energy intensive materials like metals having higher GHG savings in South Africa as compared to other countries. This underlines the interrelation of the waste management system of a country/region with other systems, in particular with energy generation, which in South Africa, is heavily reliant on coal. This study also shows that composting of garden waste is a net GHG emitter, releasing 172 and 186 kg CO2 e per tonne of wet garden waste for aerated dome composting and turned windrow composting, respectively. The paper concludes that these emission factors are facilitating GHG emissions modelling for waste management in South Africa and enabling local municipalities to identify best practice in this regard. 相似文献
737.
Hal T. Nelson 《Journal of Environmental Planning and Management》2008,51(4):581-596
Complex relationships exist between programs to reduce carbon dioxide (CO2) from the electricity sector and programs to promote renewable electricity generation. Simulation modeling of three scenarios in the UK electricity sector are used to identify potential interactions between these programs. A strict CO2 cap can result in a renewable electricity requirement being easily met. Conversely, the renewables quota could be required under low natural gas prices to keep electricity suppliers from switching from coal to gas. Similarly, CO2 trading can reduce renewables deployment levels because purchased CO2 allowances replace renewables. Therefore, both programs are required to ensure CO2 and renewables goals. The planning implications for administrative procedures and renewables subsidies are also discussed. 相似文献
738.
城市空间形态与碳排放的关系是低碳城市建设的理论依据。基于WOS和CNKI数据库,采用CiteSpace软件对1991—2022年城市空间形态与碳排放的关系进行了综述。从发文趋势、合作网络、突现词探测、关键词分析等角度,分析了该领域的发展动态、研究热点,并通过关键词聚类对文献相关内容进行综合解析。结果表明:(1)1991—2022年该领域发文量总体呈上升趋势,在国际重要事件节点上,发文量有大幅上升。(2)中国是该领域发文最多的国家,发文量达34.03%,美国发文中心性最高,为0.48,且国家、机构合作紧密。(3)关键词共现表明探究城市形态对碳排放的影响一直是学术界关注的热点;突现词探测表明研究重心逐渐从与交通碳排放相关的城市空气质量转移到与城市形态和碳排放有关的内容上来。(4)从关键词聚类标签来看,国内外将城市碳排放测算作为重中之重,并通过指标量化城市空间形态分析城市形态对碳排放的驱动作用;通过建立模型定量探讨城市空间形态与碳排放的关系是未来的研究趋势。未来应编制规范的城市层面碳排放清单以提高测算精度、拓宽城市形态与碳排放关系的研究尺度、深入挖掘三维城市空间形态与碳排放的关系。 相似文献
739.
George Mavrotas Sotiria Skoulaxinou Nikos Gakis Vassilis Katsouros Elena Georgopoulou 《Waste management (New York, N.Y.)》2013,33(9):1934-1949
In this study a multi-objective mathematical programming model is developed for taking into account GHG emissions for Municipal Solid Waste (MSW) management. Mathematical programming models are often used for structure, design and operational optimization of various systems (energy, supply chain, processes, etc.). The last twenty years they are used all the more often in Municipal Solid Waste (MSW) management in order to provide optimal solutions with the cost objective being the usual driver of the optimization. In our work we consider the GHG emissions as an additional criterion, aiming at a multi-objective approach. The Pareto front (Cost vs. GHG emissions) of the system is generated using an appropriate multi-objective method. This information is essential to the decision maker because he can explore the trade-offs in the Pareto curve and select his most preferred among the Pareto optimal solutions. In the present work a detailed multi-objective, multi-period mathematical programming model is developed in order to describe the waste management problem. Apart from the bi-objective approach, the major innovations of the model are (1) the detailed modeling considering 34 materials and 42 technologies, (2) the detailed calculation of the energy content of the various streams based on the detailed material balances, and (3) the incorporation of the IPCC guidelines for the CH4 generated in the landfills (first order decay model). The equations of the model are described in full detail. Finally, the whole approach is illustrated with a case study referring to the application of the model in a Greek region. 相似文献
740.
开展稻田温室气体排放量化评估,明确稻田温室气体(greenhouse gases,GHGs)排放的构成、分布及其变化趋势,是推进农业绿色可持续发展的重要前提。基于生命周期评价法(life cycle assessment,LCA),筛选集成稻田CO2、CH4、N2O排放评估模型,提出市域尺度稻田GHGs排放核算框架,并量化分析2001—2017年台州市不同类型水稻GHGs排放的构成、分布及其变化趋势。结果表明:(1)水稻单位面积碳足迹呈现上升趋势,单位产量碳足迹呈下降趋势;单季稻单位面积碳足迹最高(8467 kg∙hm−2,以CO2计,余同),连作晚稻单位产量碳足迹最高(1.28 kg∙kg−1)。(2)2001—2017年台州市水稻田GHGs排放总量呈下降趋势,从1110.52 Gg(以CO2计,余同)降至557.23 Gg;2017年水稻GHGs排放主要集中于温岭市(131.39 Gg)、临海市(121.64 Gg),玉环市排放量最低(9.37 Gg),早稻和连作晚稻GHGs排放主要集中在温岭市,单季稻GHGs排放集中于临海市。(3)在农资投入碳足迹构成中化肥占比最大(50.46%),单位面积碳足迹结构中CH4占比最大(75.26%)。通过展开在市域尺度上水稻GHGs排放的核算过程,旨在为农田系统的碳排放提供更加精细化的计算方式,并为寻找更有效的碳减排路径及农田系统的可持续发展提供科学支撑。 相似文献