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991.
992.
单模辐射场与N个原子相互作用理论 总被引:1,自引:0,他引:1
用玻色算符的三维型哈密顿量描述单模辐射场与N个两能级原子的相互作用。在原子系统处于低能态。光子数很大的初始条件下,得到了作用系统的动力学变化规律。 相似文献
993.
A two dimensional plane-stress finite-element type of analysis is presented to predict the behaviour of geogrids embedded
in sand under pullout loading conditions. In the analysis the interactions between soil and geogrid are simulated by non-linear
springs. The stiffnesses of the springs can be determined from simple tests in a specially designed pullout box. The proposed
finite element (FE) analysis is applied to interpret test results from a large scale pullout test rig. The predicted behaviour
of the geogrid under pullout load agrees well with the observed data including the load-displacement properties, the displacement
distribution along the longitudinal direction and the mobilisation of the frictional and bearing resistance. 相似文献
994.
The purpose of this paper is to investigate the interplay between the chemical shielding anisotropy and quadrupole interaction in MQMAS spectra.
in the compounds Na3Co(NO2)6 and trans-Co[(en2)(NO2)2]NO3 provides model systems for such an investigation. Furthermore, only few results have been reported on the application of the MQMAS method to a spin I=7/2. The possibilities of the MQMAS spectroscopy for determining the relative orientation of the two tensors and its advantage over previous techniques are discussed. Reported experimental spectra at different spinning speeds of Na3Co(NO2)6 are accurately reproduced by our theoretical simulations. The calculations are based on a recent approach, summarized in the present paper, which allows one to perform efficient simulations of MQMAS spectra including all interactions and their time-dependence throughout the experiment. This is necessary for calculating accurate MQMAS spectra including the spinning sideband pattern. In the case of trans-Co[(en2)(NO2)2]NO3 where the quadrupolar interaction and chemical shielding are stronger and their axes are non-coincident, the MQMAS spectrum is strongly distorted due to the unsufficient spinning speed and RF power. In this case, MAS at different spinning speeds is shown to provide valuable information. 相似文献
995.
Xingshi Zheng Xizhang Luo Chunguang Lin Yikun Lin 《International Journal of Infrared and Millimeter Waves》1995,16(12):2173-2179
The principle of Raman gain superposition was introduced to the theory of multi-Raman- processes interaction. Spectral characteristics of Raman lines from miniature NH3-optically pumped FiR lasers were studied and measured.supported by the National Nature Science Foundation of P.R.C. and the Special Research Foundation of Doctorate Stations of P.R.C. 相似文献
996.
本文讨论了电量有限的点电荷与导体球和电量无限小的点电荷与导体间相互作用的问题,同时澄清了以往人们对该问题的一些错误认识。 相似文献
997.
首先研究了非线性饱和光纤中各阶孤子存在的幅值范围,与标准非饱和情况的非线性薛定谔孤子非常不同,即一阶孤子幅值范围是1.4≤N≤∵.0,二阶孤子为4.0≤N≤♀.0,三阶孤子为7.0≤N≤≤15.0,并分析了各阶孤子的传输特性,最后研究了双一阶孤子相作用的若干特点,明确了五个方面的特性。 相似文献
998.
999.
缪容之 《宁波大学学报(理工版)》1988,(2)
本文证明Cluster模型违背了细致平衡原理,指出了海中核子pick-up图象的不合理性。该模型的发射几率中不考虑复杂粒子正确构成的影响更是一个显著的倒退。 相似文献
1000.
Experimental results of fluid multiphase equilibria occurring in ternary mixtures of near-critical carbon dioxide, certain n-alkanols and tetradecane are presented. The following n-alkanols were used in this investigation: decanol, octanol, heptanol, hexanol and pentanol. In the ternary systems with decanol, octanol or heptanol a closed loop liquid-vapor two-phase region in the three-phase surface liquid-liquid-vapor was found. As far as the ternary system with decanol is concerned, this phenomenon is in agreement with an earlier and unexpected finding of Patton et al. (1993). In addition, it was also found in this study that the phase diagrams of the ternary mixtures with hexanol or pentanol as the n-alkanol show further complications. 相似文献