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21.
长江螺山站高水位流量关系和城陵矶(莲花塘)控制水位的研究 总被引:4,自引:0,他引:4
螺山站高水位流量关系是确定长江城陵矶(莲花糖)控制水位的基本依据,从基本的河道水力学规律出发,考虑涨落率修正、瞬时比降修正,计算各时段点的代表性比降,和相应糙率,求出均值,根据断面资料,得出高水位的稳定流曲线,并以各日流量转化的稳定流点,进行验证,精度很好,分析了河段区间流量对螺山站稳定流量的影响。阐明了螺山站稳定流量的变化情况和趋势,推求了各次大洪水的超额洪量,计算出莲花糖以上的总入流,根据现今的湖区及槽蓄容积进行洪水演进,计算1954年特大洪水的超额洪量,并分析节三峡水库拦洪后对长江中下游超额水量的影响;对莲花塘不同防洪控制水位进行了技术经济分析和评价,提出了抬高控制水位的具体建议。 相似文献
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In this paper, any two of the three anticorrosion agents, that is emulsifier (OP-10), soluble glass (Na2O·nSiO2) and glycerin (C3H8O3), were treated simultaneously on the surface of amorphous (a-) MgNi+5% Ml2Mg17 (Ml denotes the lanthanum-rich mish metal) electrode and the electrolyte. Effect of the synergistic anticorrosion treatment on charging/discharging cycle stability of the electrode was investigated. Contrasted with single treatment method, the cycling stability of the electrodes was further improved. The desirable synergistic anticorrosion method was that the electrode was treated by the soluble glass, and that OP-10 was added into the electrolyte. The cyclic voltammogram (CV) results of the electrode show clearly that the anticorrosion agent can change the electrochemical activity and mechanism of the electrode. The concentration of the anticorrosion agent in the electrolyte treated by the synergistic anticorrosion method was also investigated. The appropriate concentration of the anticorrosion agents in the electrolyte is 0.143%. 相似文献
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J. Chen J. B. Xu K. Xue J. An N. Ke W. Cao H. B. Xia J. Shi D. C. Tian 《Microelectronics Reliability》2005,45(1):137-142
Transition-metal compound TiC60 thin films were grown by co-deposition from two separated sources of fullerene C60 powder and titanium. Study of structural properties of the films, by Raman spectroscopy, atomic force microscopy, and scanning tunneling spectroscopy reveals that the films have a deformed C60 structure with certain amount of sp3 bonds and a rough surface with a large number of nanoclusters. z–V tunnelling spectroscopic measurements suggest that several charge transport mechanisms are involved in as the tip penetrates into the thin film. Conventional field electron emission (FEE) measurements show a high emission current density of 10 mA/cm2 and a low turn-on field less than 8 V/μm, with the field enhancement factors being 659 and 1947 for low-field region and high-field region, respectively. By exploiting STM tunneling spectroscopy, local FEE on nanometer scale has also been characterized in comparison with the conventional FEE. The respective field enhancement factors are estimated to be 99–355 for a gap varying from 36 to 6 nm. The enhanced FEE of TiC60 thin films can be ascribed to structural variation of C60 in the films and the electrical conducting paths formed by titanium nanocrystallites embedded in C60 matrix. 相似文献
29.
Recently, in our laboratory a closed form expression for the correlation function of the hard-sphere dimer fluid obtained
from Wertheims multidensity Ornstein-Zernike integral equation theory with Percus-Yevick approximation was presented by Kim
et al. [2001]. However, it is difficult to apply its expression to perturbation theory and vapor-liquid equilibria calculations,
since it is of very complex form. In this work, we present a simplified expression for the first shell of the radial distribution
function (RDF) of the hard-sphere dimer fluid using a series expansion of the analytical expression. The expansion is carried
out in terms of both the packing fraction and the radial distance. Expressions are also obtained for the coordination number
and its first and second derivatives as functions of radial distance and packing fraction. These expressions, which are useful
in perturbation theory, are simpler to use than those obtained from the starting equation, while giving good agreement with
the original expression results. Then we present an simplified equation of state for the square-well dimer fluid of variable
well width (λ) based on Barker-Henderson perturbation theory using its expression for the radial distribution function of
the hard-sphere dimer fluid, and test its expression with NVT and Gibbs ensemble Monte Carlo simulation data [Kim et al.,
2001]. 相似文献
30.
Nguyen An Tien I. Ya. Mittova O. V. Almjasheva S. A. Kirillova V. V. Gusarov 《Glass Physics and Chemistry》2008,34(6):756-761
Nanocrystalline LaFeO3 is prepared by the dehydration of coprecipitated lanthanum and iron(III) hydroxides. It is shown that the behavior of the samples during heating and the size distribution of LaFeO3 nanocrystals can be considerably different depending on the scheme used for coprecipitation of lanthanum and iron hydroxides; independently of the method employed for coprecipitation of the initial compounds, sintering of the samples at 950°C leads to the formation of lanthanum orthoferrite crystals up to 100 nm in size. 相似文献