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以京津冀2020年318个地面监测站点的PM2.5数据为估算因子,构建了时空线性混合效应模型(STLME)和时空嵌套线性混合效应模型(STNLME),为AOD数据的补值研究提供了一种新方法.结果表明:在有AOD-PM2.5匹配数据的日期,上述两个模型估算精度相近,交叉验证后决定系数R2分别为0.868和0.874,均方根误差RMSE分别为0.112和0.109;在无AOD-PM2.5匹配数据的日期,嵌套模型估算精度明显高于非嵌套模型,交叉验证后决定系数R2分别为0.63和0.26.经过模型补值后,研究区监测站点所在网格AOD数据空间维有效比率从原始数据的44.35%提高到99.35%,时间维有效比率从87.94%提高到100%;同时,每个站点的年均AOD值都有明显提高,弥补了高PM2.5浓度条件下缺失的AOD数据,可以减少空气污染和健康研究中暴露评估的偏差. 相似文献
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Luis M. Romeo Sergio Espatolero Irene Bolea 《International Journal of Greenhouse Gas Control》2008,2(4):563
Absorption by chemical solvents combined with CO2 long-term storage appears to offer interesting and commercial applicable CO2 capture technology. However one of the main disadvantages is related to the large quantities of heat required to regenerate the amine solvent that means an important power plant efficiency penalty. Different studies have analyzed alternatives to reduce the heat duty on the reboiler and the thermal integration requirements on existing power cycles. In these studies integration principles have been well set up, but there is a lack of information about how to achieve an integrated design and the thermal balances of the modified cycle flowsheet. This paper proposes and provides details about a set of modifications of a supercritical steam cycle to overcome the energy requirements through energetic integration with the aim of reducing the efficiency and power output penalty associated with CO2 capture process. Modifications include a new designed low-pressure heater flowsheet to take advantage of the CO2 compression cooling for postcombustion systems and integration of amine reboiler into a steam cycle. It has been carried out several simulations in order to obtain power plant performance depending on sorbent regeneration requirements. 相似文献
207.
Selcuk Mistikoglu 《International Journal of Green Energy》2016,13(12):1281-1291
The increasing awareness of environmental issues attracts more attention on environmentally friendly energy sources. This leads to increasing research on effective use of renewable energy sources. Among them, wave energy offers a high potential. The wave energy converter systems used for transforming the wave energy into electrical energy have been a main research topic for decades. However, only a few of these systems has been successfully implemented. There seems to be some technical problems one of which is on their control applications. It has been reported that by means of appropriate control implementation, the performance of the wave energy converter system could be improved considerably. In literature, many different control techniques are reported. They appear to be weak due to implementation related restrictions. The present study proposes a novel control technique that is far more practical based on quantization of control settings. Various quantization levels and their effect on system power capture performance are studied. The technique assumes use of realistic off-the-shelf components with realistic features. The proposed method utilizes time-series-analysis technique with online parameter estimation feature. This new method does not require any knowledge of previous or future states of any of the system or sea state parameters, but only the currently available and measurable ones. The approach of the new control technique sets it apart from most of the previously reported ones. Therefore, the proposed technique is not only very much practical but also very much useful in improvement of the system power performance relative to passive techniques. 相似文献
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王滩电厂脱硫系统经济运行初探 总被引:1,自引:0,他引:1
介绍了王滩电厂2×600MW机组石灰石—石膏湿法脱硫系统实现经济运行的经验,提出了降低电耗、水耗、石灰石耗量的具体措施。王滩电厂脱硫装置已投运三年多,其运行实践表明,通过采取上述措施,在额定工况下可保证脱硫效率达95%,且脱硫系统多项运行指标均优于设计值。 相似文献
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Research on precipitation carried out systematically at the University station at Jeziory in the Wielkopolski National Park
(western Poland) allowed the determination of pollutants deposited with precipitation in this forest ecosystem. During 13 years
of study, the pH of precipitation was found to persist at a low level (4.33 on average), which resulted a substantial deposition
of H+. Values of acidifying and basic ions deposited in this area were determined and compared with the respective figures obtained
at selected EMEP stations studying background pollution, the means for Poland, and areas subjected to considerable human impact.
The use of the critical load function made it possible to establish that the S and N deposition for 2002–2005 were below its
line. 相似文献