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941.
We study the measurement-induced disturbance (MID) in a 1D optical lattice chain with nonlinear coupling. Special attention is paid to the difference between the thermal entanglement and MID when considering the influences of the linear coupling constant, nonlinear coupling constant and external magnetic field. It is shown that MID is more robust than thermal entanglement against temperature T and external magnetic field B, and MID may reveal more properties about quantum correlations of the system, which can be seen from the point of view that MID can be nonzero when there is no thermal entanglement and MID can detect the critical point of quantum phase transition at finite temperature. 相似文献
942.
Employing the off-diagonal Bethe ansatz method proposed recently by the present authors, we exactly diagonalize the XXX spin chain with arbitrary boundary fields. By constructing a functional relation between the eigenvalues of the transfer matrix and the quantum determinant, the associated T–Q relation and the Bethe ansatz equations are derived. 相似文献
943.
Margherita Albano Emma Barchiesi Roberto Biancardi Marco Dossi Giuliana Geniram Paola Vaccarono 《Macromolecular Symposia》2013,324(1):41-48
Summary: In this work an investigation of the chain end groups produced in the free radical copolymerization of vinilydene fluoride (VDF) and hexafluoropropylene (HFP) is performed. Type and amount of chain end groups are evaluated by a meticulous analytical characterization of VDF/HFP copolymer. At first pulsed gradient spin-echo nuclear magnetic resonance (spin-echo NMR) is used to identify all the chain end groups also at very low concentration (equal to 0.1 mmol · Kg−1). The instrument sensitivity is increased of an order of magnitude in comparison with the traditional NMR. Moreover potentiometric titration and ion chromatography (IC) are also used to study the chain end groups and, as a consequence, the nature and the amount of the acidity showed by the polymer chains. In details two intensity of acidity are detected by potentiometric titration, namely strong and weak. The strong acidity is associated to the presence of residual surfactant and can be removed washing the polymer, while the weak acidity is due to free molecules of fluoride acid (HF). The standard ion chromatography facility is properly modified to quantify the fluoride in the polymer matrix without any pre extraction in water. Thanks to this the HF concentration in the polymer is evaluated with high accuracy. A detailed kinetic scheme for the VDF/HFP polymerization is also proposed taking into account all the findings obtained studying the chain end groups. 相似文献
944.
945.
Akalu Tefera Aklilu Zeleke 《International Journal of Mathematical Education in Science & Technology》2013,44(8):1091-1096
In this note we present a class of functions (f, g) that satisfy ‘freshman rules’ in calculus. 相似文献
946.
Jan Uliczka 《代数通讯》2013,41(10):3401-3409
947.
948.
If a domain R, with quotient field K, has a finite saturated chain of overrings from R to K, then the integral closure of R is a Prüfer domain. An integrally closed domain R with quotient field K has a finite saturated chain of overrings from R to K with length m ≥ 1 iff R is a Prüfer domain and |Spec(R)| =m + 1. In particular, we prove that a domain R has a finite saturated chain of overrings from R to K with length dim(R) iff R is a valuation domain and that an integrally closed domain R has a finite saturated chain of overrings from R to K with length dim (R) +1 iff R is a Prüfer domain with exactly two maximal ideals such that at most one of them fails to contain every non-maximal prime. The relationship with maximal non-valuation subrings is also established. 相似文献
949.
讨论了具有离散参数的绕积马氏链的中心极限定理,给出了加在过程样本函数上充分条件。得到了绕积马氏链的中心极限定理成立的充分条件. 相似文献
950.
《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(3-4):275-303
The aim of this paper is to prove a limit theorem on the weak convergence of a family of rescaled Markov chains in a quadrant with boundary reflection. The limiting process is specified in terms of solutions of a certain submartingale problem in the style used by Varadhan and Williams. The obtained result is then applied to the problem of approximating an arbitrary Brownian motion with oblique reflection in a wedge by a family of Markov chains. 相似文献