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《中国科学E辑(英文版)》2005,(Z2)
Land surface evapotranspiration is one of the most important components in water cycle between earth and atmosphere, and plays a very important role in the atmosphere, hydrosphere, and biosphere of the planet. It is an urgent task to understand the evapotranspiration process over different surface types and conditions in agriculture, hydrogeology, forest, and ecology for the purpose of using water resources properly. Additionally, land surface evapotranspiration is a key parameter in the synop… 相似文献
3.
HYSYS过程模拟软件在空分设备操作中的应用 总被引:1,自引:1,他引:1
描述了HYSYS过程模拟软件在空分设备操作中的应用,并介绍了软件应用过程中的体会。 相似文献
4.
从产业组织的角度看,我国钢铁产业在蓬勃快速发展的背后,其产业组织结构存在着严重的不合理状况,主要表现在产业集中度低,规模经济性差,进入壁垒低等方面,使得产业的市场绩效低下,其反作用又促使产业结构矛盾加剧。这种相互作用的结果,已成为影响我国钢铁产业持续健康发展的主要原因。因此,必须从市场和产业组织政策两方面着手加以解决。 相似文献
5.
罗红 《制冷空调与电力机械》2004,25(4):55-58
通过对会展建筑中的大空间展厅的火灾情形、排烟量及排烟方式的分析,得出了一个适合此类建筑的排烟系统设计的经济合理的参考方案. 相似文献
6.
This paper introduces a measuring method of early lateral energy fraction in the scale model experiments. According to the interference principle of half wave length making the high frequency figure-8 directional microphone. With the signal-processing technique, a receiving and analyzing system, for the measurements of lateral energy fraction in the scale model is realized. 相似文献
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8.
V. Senthilkumar ;Le C. Tam ;Yong Soo Kim ;Yumin Sim ;Maeng-Je Seong ;Joon. I. Jang 《Nano Research》2014,(12):1759-1768
There has been growing research interest in the use of molybdenum disulfide in the fields of optoelectronics and energy harvesting devices, by virtue of its indirect-to-direct band gap tunability. However, obtaining large area thin films of MoS2 for future device applications still remains a challenge. In the present study, the amounts of the precursors (S and MOO3) were varied systematically in order to optimize the growth of highly crystalline and large area MoS2 layers by the chemical vapor deposition method. Careful control of the amounts of precursors was found to the key factor in the synthesis of large area highly crystalline flakes. The thickness of the layers was confirmed by Raman spectroscopy and atomic force microscopy. The optical properties and chemical composition were studied by photoluminescence (PL) and X-ray photoelectron spectroscopy. The emergence of strong direct excitonic emissions at 1.82 eV (A-exciton, with a normalized PL intensity of -55 × 10^3) and 1.98 eV (B-exciton, with a normalized PL intensity of -5 × 10^3) of the sample at room temperature clearly indicates the high luminescence quantum efficiency. The mobility of the films was found to be 0.09 cm^2/(V.s) at room temperature. This study provides a method for the controlled synthesis of high-quality two-dimensional (2D) transition metal dichalcogenide materials, useful for applications in nanodevices, optoelectronics and solar energv conversion. 相似文献
9.
Monitoring data from the Three Gorges Project show that the resulted tensile stresses are mainly distributed within the front section of the internal anchoring section which is often measuring 2.5 m in length. The composition of two early strength cement grout mixes marked as R3350 and R7350 was successfully developed to accelerate anchoring facilities installation and to reduce its intervention with the shiplock construction. It was measured that the ground water pH value in the sidewall slopes of the permanent navigation shiplock during the construction period was close to 8. Based on those characteristics it is concluded that the groundwater is weakly corrosive to steel material and will appear as non-corrosive to the steel wire strands embedded in the cement grout set. The advanced model of 3 MN unbonded anchor cables with double anti-corrosion protection (including the corrugated pipe) is developed to meet the needs of stabilizing the high sidewall rock slopes of the permanent navigation shiplock on the Three Gorges Project. 相似文献
10.
在总结神华煤及与其他动力煤配煤特性的基础上,重点分析神华煤与其他动力煤不同掺烧比条件下锅炉运行的经济性能、环保性能及其他性能,突出神华煤在火电机组"上大压小"中的重要作用。 相似文献