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991.
Jinying XuXiangdong Zhang 《Physics letters. A》2011,375(13):1524-1527
We present a rigorous multiple-scattering method to calculate the interaction energies due to electromagnetic field fluctuations in a cluster of parallel cylinders. Various kinds of cluster structure with both isotropic and anisotropic materials are considered. It is shown that Casimir interactions are sensitive to the positions of the cylinders in the cluster or the structure of the system. The sign of the interaction energy cannot only be changed by tuning the parameters of anisotropic materials, it can also be caused by changing the cylinders configuration of the system. 相似文献
992.
Seyma Akkaya DevirenErhan Albayrak 《Physica A》2011,390(20):3283-3289
The stationary states of the kinetic spin-1 Blume-Capel (BC) model on the Bethe lattice are analyzed in detail in terms of recursion relations. The model is described using a Glauber-type stochastic dynamics in the presence of a time-dependent oscillating external magnetic field (h) and crystal field (D) interactions. The dynamic order parameter, the hysteresis loop area and the dynamic correlation are calculated. It is found that the magnetization oscillates around nonzero values at low temperatures (T) for the ferromagnetic (F) phase while it only oscillates around zero values at high temperatures for the paramagnetic (P) phase. There are regions of the phase space where the two solutions coexist. The dynamic phase diagrams are obtained on the (kT/J,h/J) and (kT/J,D/J) planes for the coordination number q=4. In addition to second-order and first-order phase transitions, dynamical tricritical points and triple points are also observed. 相似文献
993.
Daniel P. Snowman 《Physica A》2011,390(9):1505-1515
Renormalization-group methods are used with a hierarchical lattice to model a Blume-Capel spin glass with annealed vacancies and competing crystal-field interactions. The strength of competing cross-link interactions is progressively increased as the effects, upon the phase diagrams, are investigated. A series of phase diagrams have been produced, sinks interpreted, and critical exponents calculated for higher order transitions. 相似文献
994.
In this paper we propose a model-independent method to extract the resonance parameters on the lattice directly from the Euclidean 2-point correlation functions of the field operators at finite times. The method is tested in case of the two-point function of the Δ-resonance, calculated at one loop in Small Scale Expansion. Further, the method is applied to a 1+1-dimensional model with two coupled Ising spins and the results are compared with earlier ones obtained by using Lüscher's approach. 相似文献
995.
996.
We consider in this article a model of vesicle moving into a viscous incompressible fluid. The vesicle is described through a phase–field equation and through a transport equation modeling the local incompressibility of its membrane. The equations for the fluid are the classical Navier–Stokes equations with a force resulting from the presence of the vesicle. Our main result states the existence of weak solutions for the corresponding system. The proof is based on compactness/monotonicity arguments. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
997.
998.
《Communications in Nonlinear Science & Numerical Simulation》2014,19(11):3969-3987
By means of symbolic computation and Darboux transformation, analytically and numerically investigated in this paper is a two-coupled Sasa–Satsuma system, which can describe the pulse propagation in birefringent fibers, so as to increase the bit rate in optical fibers, or achieve wavelength-division multiplexing. Analytical bright N-soliton solution of the system is firstly derived. Based on the bright one- and two-soliton solutions, numerical simulation and figure illustration are carried out on through the multi-parametric management, i.e., different choices among eight parameters in the two-soliton solutions. The interaction mechanisms for the bright two-solitons are revealed in three aspects: Separating evolution behaviors, elastic collision behaviors and inelastic collision behaviors. There exist three different cases for the inelastic collision for the two-soliton, which reflect correspondingly different energy transfer mechanisms (by intensity redistribution) between the two components: Manakov-typed collision; a near-elastic collision and another completely inelastic collision between the two components; and four single-solitons in two components undergo shape changes (inelastic and elastic) due to intensity redistribution, where one single-soliton keeps invariant and the other three single-solitons change during the collision. The collision mechanisms may be viewed as the two-solitons interact in a waveguide supporting propagation of two nonlinear waves simultaneously. In general, partial suppression (enhancement) of intensity between the components is dependent on the values of the soliton parameters. 相似文献
999.
利用孤立子方程KdV-mKdV的朗斯基解的形式和结构,我们提出了朗斯基形式展开法,运用这一方法获得了KdV-mKdV方程的丰富的新的复合函数解,并且朗斯基行列式中的元素不满足任何线性偏微分方程组.所得到的复合函数解是使用其它的方法得不到的. 相似文献
1000.
Chang‐xi Wang Jia‐li Li Xue‐ding Wang Long‐shan Liu Xiao Chen Min Huang 《Biomedical chromatography : BMC》2010,24(4):399-405
A liquid chromatography/tandem mass spectrometry (LC‐MS/MS) method was developed and validated for determining tacrolimus (FK506) in rat tissues to study the effect of Schisandra sphenanthera extract on FK506 tissue distribution. After a liquid–liquid extraction with ethyl acetate, FK506 and ascomycin (IS) were subjected to LC‐MS/MS analysis using positive electrospray ionization under multiple reactions monitoring mode. Chromatographic separation of FK506 and ascomycin was achieved on a Hypersil BDS C18 column with a mobile phase consisting of methanol‐water (containing 2 mM ammonium acetate, 95 : 5, v/v). The intra‐ and inter‐batch precision of the method were less than 8.8 and 9.8%, respectively. The intra‐ and inter‐batch accuracies ranged from 97.5 to 104.0%. The lowest limit of quantification for FK506 was 0.5 ng/mL. The method was applied to a FK506 tissue distribution study with or without a dose of Wuzhi (WZ) tablet. Most of the FK506 tissue concentrations were slightly increased after a concomitant WZ tablet dose, but the whole blood concentration of FK506 was dramatically increased 3‐fold after a concomitant WZ tablet dose. These results indicated that the LC‐MS/MS method was rapid and sensitive enough to quantify FK506 in different rat tissues, and strict drug monitoring is recommended when co‐administering WZ tablet in clinical use. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献