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91.
A two-fold Cayley tree with fully q-coordinated sites is constructed and thespin-1 Blume-Capel model in the presence of an external magnetic field issolved exactly. The relevant properties such as magnetization m and squaremagnetic moment q are investigated as functions of temperature and externalmagnetic field both for ferromagnetic and antiferromagnetic couplings. Inthe study, we propose a possible mechanism of the plateau based on theexchange couplings. 相似文献
92.
用三角级数和Maple软件求Burgers方程的精确解 总被引:1,自引:1,他引:1
用三角级数试探求解Burgers方程,得到关于待定系数的非线性代数方程组,利用Maple软件求解此非线性代数方程组,进而求得Burgers方程的精确解. 相似文献
93.
有限长密绕圆柱形螺线管自感系数的精确表达式 总被引:1,自引:0,他引:1
对于有限长密绕圆柱形螺线管,首先用贝塞尔函数展开法推导出自感系数的积分形式的表达式,然后用直接积分的方法得出两个级数形式的自感系数表达式,最后对这两个表达式作了简要的分析与比较. 相似文献
94.
LIU Ping LOU Sen-Yue 《理论物理通讯》2009,51(1):27-34
The symmetries, symmetry reductions, and exact solutions of a coupled nonlinear Schrodinger (CNLS) equation derived from the governing system for atmospheric gravity waves are researched by means of classical Lie group approach in this paper. Calculation shows the CNLS equation is invariant under some Galilean transformations, scaling transformations, phase shifts, and space-time translations. Some ordinary differential equations are derived from the CNLS equation. Several exact solutions including envelope cnoidal waves, solitary waves and trigonometric function solutions for the CNLS equation are also obtained by making use of symmetries. 相似文献
95.
With the help of an objective reduction approach (ORA), abundant exact solutions of (2+1)-dimensional higher-order Boussinesq system (including some hyperboloid function solutions, trigonometric function solutions, and a rational function solution) are obtained. It is shown that some novel soliton structures, like single linearity soliton structure, breath soliton structure, single linearity y-periodic solitary wave structure, libration dromion structure, and kink-like multisoliton structure with actual physical meaning exist in the (2+1)-dimensional higher-order Boussinesq system. 相似文献
96.
MA Hong-Cai YU Yao-Dong GE Dong-Jie 《理论物理通讯》2009,51(4):609-612
In this paper, the nonlinear dispersive Zakharov- Kuznetsov equation is solved by using the generalized auxiliary equation method. As a result, new solitary pattern, solitary wave and singular solitary wave solutions are found. 相似文献
97.
Lie symmetrical perturbation and adiabatic invariants of generalized Hojman type for Lagrange systems
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Based on the invariance of differential equations under
infinitesimal transformations of group, Lie symmetries, exact
invariants, perturbation to the symmetries and adiabatic invariants
in form of non-Noether for a Lagrange system are presented. Firstly,
the exact invariants of generalized Hojman type led directly by Lie
symmetries for a Lagrange system without perturbations are given.
Then, on the basis of the concepts of Lie symmetries and higher
order adiabatic invariants of a mechanical system, the perturbation
of Lie symmetries for the system with the action of small
disturbance is investigated, the adiabatic invariants of generalized
Hojman type for the system are directly obtained, the conditions for
existence of the adiabatic invariants and their forms are proved.
Finally an example is presented to illustrate these results. 相似文献
98.
We show that the exact energy eigenvalues and eigenfunctions of the Schrödinger equation for charged particles moving in certain class of non-central potentials can be easily calculated analytically in a simple and elegant manner by using Nikiforov and Uvarov (NU) method. We discuss the generalized Coulomb and harmonic oscillator systems. We study the Hartmann Coulomb and the ring-shaped and compound Coulomb plus Aharanov–Bohm potentials as special cases. The results are in exact agreement with other methods. 相似文献
99.
The one-dimensional Klein-Gordon equation is solved for the PT-symmetric generalized Hulthén potential in the scalar coupling scheme. The relativistic bound-state energy spectrum and the
corresponding wave functions are obtained by using the Nikiforov-Uvarov method which is based on solving the second-order
linear differential equations by reduction to a generalized equation of hypergeometric type.
PACS numbers: 03.65.Fd, 03.65.Ge 相似文献
100.
Fusion,fission, and annihilation of complex waves for the(2+1)-dimensional generalized Calogero–Bogoyavlenskii–Schiff system
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With the help of the symbolic computation system, Maple and Riccati equation( ξ= a0+ a1ξ+ a22ξ), expansion method, and a linear variable separation approach, a new family of exact solutions with q = lx + my + nt + Γ(x, y,t) for the(2+1)-dimensional generalized Calogero–Bogoyavlenskii–Schiff system(GCBS) are derived. Based on the derived solitary wave solution, some novel localized excitations such as fusion, fission, and annihilation of complex waves are investigated. 相似文献