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61.
高温高压下CO2在重质烷烃中的溶解度和体积传质系数的研究 总被引:1,自引:0,他引:1
使用1L的高压搅拌釜,应用气体间歇吸收技术,在温度373-573K,DFLT1.0-4.0MPa,搅拌速度800r/min的实验范围内,测定了CO2在液体石蜡,FT300蜡中的溶解度和体积传质系数。实验结果表明CO2在上述蜡中的溶解度和体积传质是系数是温度和压力的函数。 相似文献
62.
Hartmut Backe 《Hyperfine Interactions》2006,171(1-3):93-107
Unique spectroscopic possibilities open up if a laser beam interacts with relativistic lithium-like ions stored in the heavy
ion ring accelerator SIS300 at the future Facility for Antiproton and Ion Research FAIR in Darmstadt, Germany. At a relativistic
factor γ = 36 the 2P1/2 level can be excited from the 2S1/2 ground state for any element with frequency doubled dye-lasers in collinear geometry. Precise transition energy measurements
can be performed if the fluorescence photons, boosted in forward direction into the X-ray region, are energetically analyzed
with a single crystal monochromator. The hyperfine structure can be investigated at the 2P1/2−2S1/2 transition for all elements and at the 2P3/2−2S1/2 transition for elements with Z≤50. Isotope shifts and nuclear moments can be measured with unprecedented precision, in principle even for only a few stored
radioactive species with known nuclear spin. A superior relative line width in the order of 5·10−7 may be feasible after laser cooling, and even polarized external beams may be prepared by optical pumping. 相似文献
63.
对我国沪深300指数与沪深300指数期货的周数据进行了关联性分析.首先利用EG检验和Johansen系统检验对两指数进行协整检验,然后通过3种变结构协整模型分别检验,结果找到了变点,得到了变机构长期均衡关系和误差修正模型,同时比较了4种模型的应用效果,给出了相关的政策建议. 相似文献
64.
Alpha particle induced reactions in the target elements copper and tantalum were studied. The excitation functions of63Cu(α, n) +65Cu(α, 3n),65Cu(α, 2n),181Ta(α, 2n) and181Ta(α, 4n) were measured up to 75 MeV.Eight new energy point cross-sections were measured for the first time. The experimental results were compared with the predictions
of updated hybrid model (ALICE/85/300) as well as with index model using the initial exciton numbern
0=4 (4poh) and level density parameter,a=A/8. A general agreement was found for all the reactions with both the models. 相似文献
65.
66.
Coloration of Mn in soda-lime silicate glass by X-ray irradiation was investigated as a coloration method suitable for glass recycling. Mn was initially reduced to Mn2+ with the addition of Fe, Sn or carbon, and the resultant colorless or near-colorless glasses containing no Mn3+ were studied. These glasses turned violet after X-ray irradiation and heat treatment at 200 °C due to formation of Mn3+. The color was stable at room temperature and decoloration occurred with heat treatment at 600 °C. The addition of Fe or Sn increased the optical absorption by Mn3+ ions. ESR measurement suggests that Mn photo-oxidation occurred through charge transfer from photo-induced hole centers. 相似文献
67.
María M. Muñoz Darío A. Tinjacá Abolghasem Jouyban William E. Acree 《Physics and Chemistry of Liquids》2018,56(3):391-402
Molar volumes and excess molar volumes were investigated from measured density values for {PEG 300 (1) + ethanol (2)} binary mixtures at temperatures from 278.15 to 313.15 K. Both systems exhibit negative excess volumes probably due to increased interactions like hydrogen bonding and/or large differences in molar volumes of the components. Volume thermal expansion coefficients were also calculated for both binary mixtures and pure solvents. Refractive indices were also determined for all these non-aqueous mixtures and neat solvents at all temperatures. Furthermore, the Jouyban–Acree model was used for density, molar volume and refractive index correlations of the studied mixtures at different temperatures. The mean relative deviations between experimental and back-calculated density, molar volume and refractive index data were 0.07%, 0.99% and 0.01%, respectively. 相似文献
68.
69.
通过对湿热环境下阶梯挖补胶接修理后碳纤维/双马树脂(T300/QY8911)层合板振动特性的分析,探究了挖补修理后碳纤维/双马树脂层合板在不同湿热效应下的振动特性。基于Mindlin-Reissner板理论与最小势能变分原理,在考虑湿热效应前提下,推导了正交各向异性复合材料层合板的本构关系及四边简支条件下的自由振动控制方程;其次,利用ABAQUS软件建立了三维黏弹性有限元挖补修理模型,应用Fortran语言将湿热耦合下的应力-应变本构关系编入UMAT二次开发文件中,采用三维八节点五自由度等参单元进行了离散。通过与参考文献对照,验证了胶接修理后T300/QY8911层合板有限元模型和编译的湿热环境下UMAT子程序的合理性与有效性。算例结果表明:湿热环境对挖补修理后层合板固有频率的影响比对完整层合板严重;温度对材料性能的影响大于湿度;相比于材料性能变化对振动特性的影响,湿热残余应力对胶接修理后层合板振动特性的影响占主导;参考环境下,胶接修理后层合板的固有频率增大;湿应力对层合板固有频率的影响大于热应力。 相似文献
70.
本研究利用2006年10月30日至2009年3月13日期间的仿真的沪深300指数期货每日结算价,探讨了期货价格的不对称跳跃波动行为。在实证研究方法上,本文以Chan和Maheu的GARCH(1,1)-ARJI模型为基础并进行了扩展,以EGARCH(1,1)-CJI和EGARCH(1,1)-ARJI两种模型来刻画股指期货价格的不对称和跳跃波动行为。实证结果显示:(1)沪深300仿真股指期货价格存在不对称跳跃波动,而且跳跃强度不为一固定常数,异常信息所产生的跳跃强度是随着时间变动的。(2)经过似然比检验,结果显示EGARCH(1,1)-ARJI模型比EGARCH(1,1)-CJI模型具有更好的拟合能力。 相似文献