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871.
We present a spring-defect model in 3-dimensions to describe the connection between elastic distortion and interstitial carbon
ordering associated with phase transition from a body centred cubic (BCC) to body centered tetragonal (BCT) structure in BCC
metals such as α-iron. The presence or the absence of the carbon is modelled in terms of a pseudo spinŝ=+1or -l.An Ising interaction between carbon atoms is recovered after eliminating the lattice degrees of freedom, which is
longranged. The coupling between the spin and lattice degrees of freedom allows for a systematic study of ferroelasticity
and the variation of the lattice parameter with carbon concentration. The mean field results for the paraelastic to ferroelastic
transition, lattice parameter and static compliance are presented. The significant feature of this calculation is not only
a derivation of the defect-defect interaction, but also an explicit calculation of the strain dipole tensor associated with
each defect, from a microscopic model. 相似文献
872.
Jiang Jiahe 《数学学报(英文版)》1997,13(4):473-486
As important applications of minimax-type inequalities for a family of functions in [3], in the present paper there are given
a number of existence theorems on simultaneous solutions to fixed point and minimax-type inequality problems and to fixed
point and variational-type inequality problems, not only abolishing the paracompactness hypothesis on the underlying space
and weakening the others in the results in [1], but also making them still nicer in form with still more concise and straightforward
proofs.
Supported both by the National Natural Science Foundation of China and by the Institute of Mathematics, Academia Sinica 相似文献
873.
Ignacio Villanueva 《Czechoslovak Mathematical Journal》2004,54(2):373-378
We use polymeasures to characterize when a multilinear form defined on a product of C(K, X) spaces is integral. 相似文献
874.
Wei Zhao R. Lukic-Zrnic B. P. Gorman R. L. Cottier T. D. Golding C. L. Littler J. H. Dinan L. A. Almeida J. A. Dura R. M. Lindstrom H. F. Schaake P. Liao 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):246
Hg1−xCdxTe(x0.22) samples grown by LPE on CdZnTe(111B)-oriented substrates were exposed to various doses of thermal neutrons (1.0×1016−1.7×1016 n/cm2) and subsequently annealed for 24 h in Hg overpressure to remove damage and reduce the presence of Hg vacancies. Extensive magnetotransport measurements were performed on these samples as part of an investigation into the use of elemental transmutation for efficient p-type doping of this material. The data were analyzed using a multi-carrier approach which incorporates various scattering mechanisms and the presence of two conduction channels of differing alloy content to describe the changes in the transport properties due to neutron irradiation. 相似文献
875.
本文证明了S^n中Moebius形式为零且法丛平坦的曲面的余维数约化定理,并且给出了这类曲面的分类.在此基础上,进一步给出了S^n中Moebius形式为零的曲面的分类. 相似文献
876.
漆芝南 《南昌大学学报(理科版)》2003,27(2):103-105
引入了弱奇异元的概念,得到了若干重要性质和相关结果:1.L的每个非零元是弱奇异元当且仅当L∈A;2.L∈Fs,则L的一个非零元g是弱奇异元当且仅当g是有限个基元素的并。 相似文献
877.
Sylvia Pulmannová 《Reports on Mathematical Physics》2004,53(2):301-316
A definition of a tensor product in the category of Hilbert space effect algebras is introduced such that the tensor product reflects as much as possible of the physically important properties of the components. It is shown that in the complex case, there are two candidates to the tensor product, which are not equivalent. The situation is similar to the tensor product in the category of projection lattices, but also the two dimensional case is included. The case of tensor product of two classical systems is also investigated. 相似文献
878.
T. Sumikama T. Iwakoshi T. Nagatomo M. Ogura Y. Nakashima H. Fujiwara K. Matsuta T. Minamisono M. Mihara M. Fukuda K. Minamisono T. Yamaguchi 《Hyperfine Interactions》2004,159(1-4):281-284
The pure nuclear spin alignments of 8Li and 8B were produced from the nuclear spin polarization applying the β-NMR method. The alignment correlation terms in the β-ray angular distribution were observed to test the G parity conservation in the nuclear β decay. 相似文献
879.
关于积和式差的一点注记 总被引:1,自引:0,他引:1
It is shown that for any two n×n complex valued matrices A, B the inequality |perA-perB|≤n‖A-B‖Fmax(‖A‖F,‖B‖F)n-1 or |perA-perB|≤‖A‖Fn ‖B‖Fn holds for where AH denotes the conjuagte transpose of the matrix A=(aij)n×n. 相似文献
880.
Mario Piris Alberto Martinez Peter Otto 《International journal of quantum chemistry》2004,97(4):827-831
Recently, we proposed a new natural orbital functional for taking into account the electronic correlation in molecular systems. Calculation of dipole moments and polarizabilities of eight selected molecules are presented. By comparison with other correlated methods, it is shown that the method has predictive capabilities for these properties. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 相似文献