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991.
Coupled-cluster calculation of dispersion contributions to interaction energies and polarizabilities
The induced dipole dispersion-type contributions to the two-body and nonadditive three-body energies and electric dipole
polarizabilities are studied for long-range interactions involving the He, Ne, Ar and Kr atoms and the H2 and N2 molecules. The coupled-cluster singles and doubles model and large basis sets are used. Comparison of the energy contributions
with data derived from experiment shows in most cases the deviations to be less than 1%; therefore, it may be expected that
the calculated polarizability increments are accurately determined and can be used to estimate the accuracy of approximate
methods.
Received: 20 March 2001 / Accepted: 5 April 2001 / Published online: 27 June 2001 相似文献
992.
993.
T. Kato K. Miyashita S. Iwata S. Tsunashima H. Sakakima Y. Sugita Y. Kawawake 《Journal of magnetism and magnetic materials》2002,240(1-3):168-170
Temperature dependence of the giant magneto-resistance (MR) was measured for spin valves with and without nano-oxide layer (NOL). In spin valves with NOL, the MR ratio increased more remarkably on lowering the temperature than in those without NOL. The temperature dependence of MR ratio and that of the resistivity were explained by using two-current model. The MR ratio enhanced with NOL is attributed to the increase of the mean free path of up-spin electrons. 相似文献
994.
In this paper, we demonstrate how a new network performance/efficiency measure, which captures demands, flows, costs, and
behavior on networks, can be used to assess the importance of network components and their rankings. We provide new results
regarding the measure, which we refer to as the Nagurney–Qiang measure, or, simply, the N–Q measure, and a previously proposed
one, which did not explicitly consider demands and flows. We apply both measures to such critical infrastructure networks
as transportation networks and the Internet and further explore the new measure through an application to an electric power
generation and distribution network in the form of a supply chain. The Nagurney and Qiang network performance/efficiency measure
that captures flows and behavior can identify which network components, that is, nodes and links, have the greatest impact
in terms of their removal and, hence, are important from both vulnerability as well as security standpoints. 相似文献
995.
本文讨论了机器人阵列式触觉传感器的理论设计参数和实际制造参数,并用组合法辨识方法对设计参数进行了优化设计,给出了可供参考的设计值。 相似文献
996.
Xiaoming Chen Weigun Lin Liangjing Xue 《International Journal of Infrared and Millimeter Waves》1991,12(8):903-904
A way to formulate the transform in spectral domain technique is presented. 相似文献
997.
杨占民 《贵州师范大学学报(自然科学版)》1993,11(1):58-62
近年来,不少文章对教科书上的电风解释提出了不同看法,本文在实验的基础上分析了几种典型的论点,指出其中的不足,并论证了教科上的解释的正确性。 相似文献
998.
Hideo Matsumura Vassil Neytchev Nelly Terezova Iana Tsoneva 《Colloids and surfaces. B, Biointerfaces》2004,33(3-4):243-249
Phospholipid liposomes that contain Ca ions in inside compartment were subjected to external alternating electric fields of square wave form at several frequencies: 10, 100 Hz, 1, 10, 100 kHz. The leakage of Ca ions from inside to bulk solution caused by the electric fields was detected by the fluorescence change due to Ca-Quin 2 (fluorescent dye) complex formation in the bulk aqueous solution. The temperature increments of the sample solution in the chamber were also measured. The amplitude of the electric field and time interval between application of the electric field were varied. The frequency dependency of both the leakage of Ca ion and the temperature increments was observed. It was observed that the efficiency of the leakage had a minimum at 1 kHz. The origin of the frequency dependency of the leakage is discussed, and it is concluded that the energy consumption on a microscopic scale in the liposome membrane zone can be the reason for membrane permeation in this experimental system. 相似文献
999.
Moon Fuk Chan Guansan Chen M. Süleyman Demokan Hwa Yaw Tam 《Optics and Lasers in Engineering》1998,30(1):17-24
The theory and experimental verification of an optical current sensor based on an extrinsic Sagnac interferometer configuration is presented. Superior performance with regard to current sensitivity and input/output linearity, and simple installability of the sensor makes it very suitable for remote current sensing in power distribution applications. 相似文献
1000.
A. J. Shields J. L. Osborne M. Y. Simmons D. M. Whittaker F. M. Bolton D. A. Ritchie M. Pepper 《Physica E: Low-dimensional Systems and Nanostructures》1998,2(1-4)
We study the effect of an electric field applied normal to the layers on the binding energy of charged excitons (or trions) in GaAs quantum wells. We find that, in contrast to the neutral exciton, their binding energy is sharply reduced by modest electric fields. The effect is stronger for the positively charged exciton than the negatively charged one. The ionisation of the excess carrier is explained by the field-induced polarisation of the electron and hole subband wave functions. 相似文献