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991.
Based on the concept of adiabatic invariant, the perturbation to Lie-Mei symmetry and adiabatic invariants for Birkhoffian systems are studied. The definition of the perturbation to Lie-Mei symmetry for the system is presented, and the criterion of the perturbation to Lie-Mei symmetry is given. Meanwhile, the Hojman adiabatic invariants and the Mei adiabatic invariants for the perturbed system are obtained. 相似文献
992.
For any finite-dimensional semisimple Lie algebra g, a
Z+-graded vertex algebra is construsted on the vacuum
representation Vk(\hat{g}[ θ]) of \hat{g}[θ], which is
a one-dimentional central extension of θ-invariant subspace on the loop algebra
Lg=g\otimes C((t1/p)). 相似文献
993.
SHEN Xiao-Yan 《中国物理C(英文版)》2008,32(6):448-451
We reported the observation of Y(2175) in φf0(980) mass spectrum in J/ψ→ηφf0(980) with f0(980)→π+π- and the observation of a broad 1-- resonance of K+K-mass in J/ψ→K+K-π0. The results from the partial wave analyses of Jψ→γπ+π- and γπ0π0, as well as J/ψ→pK-∧. are also presented. 相似文献
994.
This paper is a sequel to a previous paper (Yang,Y.and Zhang,J.H.Existence of solutions for some fourth-order boundary value problems with parameters.Nonlinear Anal.69(2),1364–1375 (2008)) in which the nontrivial solutions to the fourthorder boundary value problems were studied.In the current work with the same conditions near infinity but different near zero,the positive,negative,and sign-changing solutions are obtained by the critical point theory,retracting property,and invariant sets. 相似文献
995.
This paper discusses a class of nonlinear Schrdinger equations with combined power-type nonlinearities and harmonic potential. By constructing a variational problem the potential well method is applied. The structure of the potential well and the properties of the depth function are given. The invariance of some sets for the problem is shown. It is proven that, if the initial data are in the potential well or out of it, the solutions will lie in the potential well or lie out of it, respectively. By the convexity method, the sharp condition of the global well-posedness is given. 相似文献
996.
Numerical simulation of nanoparticle nucleation and coagulation in a mixing layer with sulfuric acid vapor binary system is performed using the large eddy simulation and the direct quadrature method of moment. The distributions of number concentration, volume concentration, and average diameter of nanoparticles are obtained. The results show that the coherent structures have an important effect on the distributions of number concentration, volume concentration and average diameter of nanoparticles via continuously transporting and diffusing the nanoparticles to the area of low particle concentration. In the streamwise direction, the number concentration of nanoparticles decreases, while the volume concentration and the average diameter increase. The distributions of number concentration, volume concentration and average diameter of nanoparticles are spatially inhomogeneous. The characteristic time of nucleation is shorter than that of coagulation. The nucleation takes place more easily in the area of low temperature because where the number concentration of nanoparticles is high, while the intensity of coagulation is mainly affected by the number concentration. Both nucleation and coagulation result in the variation of average diameter of nanoparticles. 相似文献
997.
Heavy gauge bosons such as W' are expected to exist in many extensions of the Standard Model. In this paper, the most general Lagrangian for the interaction of W' with top and bottom quarks is considered. This Lagrangian consists of V- A and V + A structure with in general complex couplings. Such interactions produce an Electric Dipole Moment (EDM) for the top quark at one loop level. We predict the allowed ranges for the mass and couplings of W' by using the upper limit on the top quark EDM. 相似文献
998.
用分析方法研究紧的度量空间上的一类Feller算子P的遍历性质。通过P的转移概率函数π(·,·),给出了P的极小遍历集的特征。利用Riesz表示定理和平均遍历定理证明了紧的度量空间上具有遍历测度的算子P有几乎稠密的轨道。此外,在P的支集相交这一条件下,得到了算子P具有惟一不变概 相似文献
999.
The q-deformed supersymmetric t-J model on a semi-infinite lattice is diagonalized by using the level-one vertex operators of the quantum affine superalgebra
Uq[\widehat{sl(2|1)}]. We give the bosonization
of the boundary states. 相似文献
1000.
We use star representation geometric methods to obtain explicit oscillatory integral formulae for strongly invariant star products on Iwasawa subgroups AN of SU(1,n) 相似文献