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71.
苑晓丽 《原子与分子物理学报》2013,30(6)
本文主要通过平面波赝势密度泛函理论的第一性原理计算方法,采用了广义梯度近似(GGA)交换相关函数,研究了六角结构的Zr4Al2的EOS态方程和热动力学性质。通过采用了声子效应的准谐近似德拜模型,我们成功得到了晶胞体积V随温度以及V/V0、德拜温度Θ、热熔CV 随压强P的变化关系。另外,我们还研究了热膨胀系数α及格林参数γ随温度和压强的变化关系,计算结果表明格林参数和热膨胀系数随温度的升高而增加,但是在较高的温度下,热膨胀系数几乎不受温度的影响。 相似文献
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In this paper, we investigate a generalized nonautonomous nonlinear equation which describes the ultrashort optical pulse propagating in a nonlinear inhomogeneous fiber. By virtue of the generalized Darboux transformation, the first- and second-order rogue-wave solutions for the generalized nonautonomous nonlinear equation are obtained, under some variable–coefficient constraints. Properties of the first- and second-order rogue waves are graphically presented and analyzed: When the coefficients are all chosen as the constants, we can observe the some functions, the shapes of wave crests and troughs for the first- and second-order rogue waves change. Oscillating behaviors of the first- and second-order rogue waves are observed when the coefficients are the trigonometric functions. 相似文献
75.
A theory of fuzzy random variables is developed that applies to situations involving both randomness and fuzziness. The use of membership functions that are quasi-concave play an important role in the theory. The expectation of a fuzzy random variable is a fuzzy variable (fuzzy set). The usual linearity properties of probabilistic expectation carry over to fuzzy random variables. A special case of a fuzzy Law of Large Number is proven. 相似文献
76.
String theory, quantum geometry, loop quantum gravity and black hole physics all indicate the existence of a minimal observable length on the order of Planck length. This feature leads to a modification of Heisenberg uncertainty principle. Such a modified Heisenberg uncertainty principle is referred as gravitational uncertainty principle(GUP) in literatures. This proposal has some novel implications on various domains of theoretical physics. Here, we study some consequences of GUP in the spirit of Quantum mechanics. We consider two problem: a particle in an one-dimensional box and free particle wave function. In each case we will solve corresponding perturbational equations and compare the results with ordinary solutions. 相似文献
77.
构造了任意两态叠加多模泛函叠加态光场|ψ(2)f>q,利用多模辐射场广义非线性等幂次高次差压缩的一般理论,研究了态|ψ(2)f>q的广义磁场分量的非线性等幂次N次方差压缩特性.得到了一般理论结果,讨论了两种特殊两态叠加多模泛函叠加态光场的差压缩特性.结果表明:1)当qN为偶数时,第一类两态叠加多模泛函叠加态光场和虚相干两态叠加多模泛函叠加态光场都不出现广义磁场分量的非线性差压缩效应,也不处于N-j最小测不准态;2)当qN为奇数时,在一定条件下,任意两态叠加多模泛函叠加态光场中,广义磁场分量呈现出周期性变化的广义非线性N次方差压缩效应. 相似文献
78.
In this Letter, a drive-response synchronization method with linear output error feedback is presented for “generalized projective synchronization” of a class of fractional-order chaotic systems via a scalar transmitted signal. This synchronization approach is theoretically and numerically studied. By using stability theory of linear fractional-order systems, the suitable conditions for achieving synchronization are given. Two examples are used to illustrate the effectiveness of the proposed synchronization method. Numerical simulations coincide with the theoretical analysis. 相似文献
79.
The generalized Kullback-Leibler divergence (K-Ld) in Tsallis statistics [constrained by the additive duality of generalized statistics (dual generalized K-Ld)] is here reconciled with the theory of Bregman divergences for expectations defined by normal averages, within a measure-theoretic framework. Specifically, it is demonstrated that the dual generalized K-Ld is a scaled Bregman divergence. The Pythagorean theorem is derived from the minimum discrimination information principle using the dual generalized K-Ld as the measure of uncertainty, with constraints defined by normal averages. The minimization of the dual generalized K-Ld, with normal averages constraints, is shown to exhibit distinctly unique features. 相似文献
80.