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541.
Using the coherent state representation of Wigner operator and the
technique of integration within an ordered product (IWOP) of
operators, the Wigner functions of the even and odd binomial states
(EOBSs) are obtained. The physical meaning of the Wigner functions
for the EOBSs is given by means of their marginal distributions.
Moreover, the tomograms of the EOBSs are calculated by virtue of
intermediate coordinate-momentum representation in quantum optics. 相似文献
542.
采用元胞自动机模型模拟了纯物质凝固微观组织演化行为. 与以往采用KGT模型简化考虑不同,采用界面能量守恒方程来自洽地确定液固界面的生长动力学,考察了模型的网格尺寸相关性和时间相关性,并对模型的稳定性进行了验证. 采用这个模型模拟了纯丁二腈在过冷熔体中的自由枝晶生长,并与Glicksman的等温枝晶生长实验(isothermal dendritic growth experiment,IDGE)和LM-K临界稳定性原理进行了对比. 模拟的形貌再现了实验形貌的特征,并且特征参数与理论结果及实验结果符合得很好.
关键词:
元胞自动机
界面
凝固
临界稳定性原理 相似文献
543.
A. Dargys 《Optics Communications》2012,285(24):4785-4792
Connection between optical Mueller matrices and geometrical (Clifford) algebra multivectors is established. It is shown that starting from 3-dimensional (3D) Cl3,0 algebra and using isomorphism between Cl3,0 and even Cl3,1+ subalgebra one can generate canonical Mueller matrices and their combinations that describe an optical system. It appears that representation of polarization devices in terms of geometric algebra is very compact and, in contrast to Mueller matrix approach, there is no need for speculative physical restrictions. If needed, properties of media can be logically introduced into Maxwell equation in a form of Clifford algebra via constitutive relations. Since representation of polarization by Cl3,1 algebra is Lorentz invariant it allows to include relativistic effects of moving bodies on light polarization as well. In this paper only simple examples of connection between Mueller matrices and geometric algebra multivectors is presented. 相似文献
544.
Y. Kohori Y. Yamato Y. Iwamoto T. Kohara 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,18(4):601-604
We have carried out 115In nuclear quadrupole resonance (NQR) measurements in CeRhIn5. At ambient pressure, CeRhIn5 undergoes an antiferromagnetic AF phase transition at K. The 115In NQR spectrum has shown the appearance of a small internal field in the direction perpendicular to the tetragonal c-axis. With application of a hydrostatic pressure, the AF state is suppressed and the superconductivity appears just above
the critical pressure (P
= 17 kbar). The nuclear spin lattice relaxation rate 1/T1 of 115In measured at P
= 27 kbar indicates the occurrence of the superconductivity in the nearly AF region. In the superconducting state, 1/T1 has no Hebel-Slichter coherence peak just below of 2 K and has a power law T-dependence (T3) down to 300 mK. This is consistent with anisotropic superconductivity, with line nodes in the superconducting energy gap:
non-s-wave superconductivity occurs in CeRhIn5.
Received 5 July 2000 相似文献
545.
A new orthogonality relationship for orthotropic thin plate theory and its variational principle 总被引:2,自引:0,他引:2
LUO Jianhui LONG Yuqiu & LIU Guangdong . College of Civil Engineering Hunan University Changsha China . Department of Civil Engineering Tsinghua University Beijing China 《中国科学G辑(英文版)》2005,48(3):371-380
While Hamiltonian system was led to solution of elastic theory a symplectic system-atic methodology for theory of elasticity was established and a symplectic orthogonality relationship was presented[1,2]. For two-dimensional theory of elasticity a new dual vec-tor and a new dual differential matrix were presented by putting the old dual vector[1] in a new order. It was discovered for isotropic materials that the symplectic orthogonality relationship may be decomposed into two independent and s… 相似文献
546.
Emmanuel Esteve Solenn Reguer Cédric Boissiere Corinne Chanéac Gustavo Lugo Chantal Jouanneau Cristian Mocuta Dominique Thiaudière Nicolas Leclercq Bernard Leyh Jean-François Greisch Julien Berthault Michel Daudon Pierre Ronco Dominique Bazin 《Journal of synchrotron radiation》2017,24(5):991-999
The new rapid scan method, Flyscan mode, implemented on the DiffAbs beamline at Synchrotron SOLEIL, allows fast micro‐X‐ray fluorescence data acquisition. It paves the way for applications in the biomedical field where a large amount of data is needed to generate meaningful information for the clinician. This study presents a complete set of data acquired after injection of gold‐cluster‐enriched mesoporous silica nanospheres, used as potential theranostic vectors, into rats. While classical X‐ray fluorescence investigations (using step‐by‐step acquisitions) are based on a limited number of samples (approximately one per day at the DiffAbs beamline), the Flyscan mode has enabled gathering information on the interaction of nanometer‐scale vectors in different organs such as liver, spleen and kidney at the micrometer scale, for five rats, in only a single five‐day synchrotron shift. Moreover, numerous X‐ray absorption near‐edge structure spectra, which are beam‐time‐consuming taking into account the low concentration of these theranostic vectors, were collected. 相似文献
547.
V.Debierre 《理论物理通讯》2019,71(4):403-409
We propose a direct derivation of the Lorentz generators for the four-potential of electrodynamics on the basis of Wigner's theorem. The derivation relies on a study of the behaviour of polarisation vectors under k-space differentiation. The Coulomb and Lorenz gauges are discussed in that respect, and gauge invariance under Poincare′transformations is examined. The Poincar′e generators given by Bia lynicki-Birula and Bia lynicka-Birula are found to correspond to the Coulomb gauge case. 相似文献
548.
A new approach to obtaining positive-definite Wigner operator for two entangled particles with different masses 下载免费PDF全文
Based on our previously proposed Wigner operator in entangled form,we introduce the generalized Wigner operator for two entangled particles with different masses,which is expected to be positive-definite.This approach is able to convert the generalized Wigner operator into a pure state so that the positivity can be ensured.The technique of integration within an ordered product of operators is used in the discussion. 相似文献
549.
The system capacity for a single-commodity flow network is the maximum flow from the source to the sink. This paper discusses the system capacity problem for a p-commodity limited-flow network with unreliable nodes. In such a network, arcs and nodes all have several possible capacities and may fail. Different types of commodity, which are transmitted through the same network simultaneously, competes the capacities of arcs and nodes. In particular, the consumed capacity by different types of commodity varies from arcs and nodes. We first define the system capacity as a vector and then a performance index, the probability that the upper bound of the system capacity is a given pattern subject to the budget constraint, is proposed. Such a performance index can be easily computed in terms of upper boundary vectors meeting the demand and budget. A simple algorithm based on minimal cuts is thus presented to generate all upper boundary vectors. The manager can apply this performance index to measure the system capacity level for a supply-demand system. 相似文献
550.
For a scale mixture of normal vector, X=A1/2G, where X, G
n and A is a positive variable, independent of the normal vector G, we obtain that the conditional variance covariance, Cov(X2 X1), is always finite a.s. for m2, where X1
n and m<n, and remains a.s. finite even for m=1, if and only if the square root moment of the scale factor is finite. It is shown that the variance is not degenerate as in the Gaussian case, but depends upon a function SA, m(·) for which various properties are derived. Application to a uniform and stable scale of normal distributions are also given. 相似文献