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101.
102.
Utilizing the Wronskian technique, a combined Wronskian condition is established for a (3+1)-dimensional generalized KP equation. The generating functions for matrix entries satisfy a linear system of new partial differential equations. Moreover, as applications, examples of Wronskian determinant solutions, including N-soliton solutions, periodic solutions and rational solutions, are computed. 相似文献
103.
Structural, electronic, and optical properties of ZnOl_xSex alloys using first-principles calculations 下载免费PDF全文
Muhammad Rashid Fayyaz Hussain Muhammad Imraran S A Ahmadt N A Noot M U Sohmb S M Alay-e-Abbas 《中国物理 B》2013,(8):581-588
The structural, electronic, and optical properties of binary ZnO, ZnSe compounds, and their ternary ZnOl_xSex alloys are computed using the accurate full potential linearized augmented plane wave plus local orbital (FP-LAPW + lo) method in the rocksalt (B 1) and zincblende (B3) crystallographic phases. The electronic band structures, fundamental energy band gaps, and densities of states for ZnO1_xSex are evaluated in the range 0 〈 x 〈 1 using Wu-Cohen (WC) generalized gradient approximation (GGA) for the exchange-correlation potential. Our calculated results of lattice parameters and bulk modulus reveal a nonlinear variation for pseudo-binary and their ternary alloys in both phases and show a considerable deviation from Vegard's law. It is observed that the predicted lattice parameter and bulk modulus are in good agreement with the available experimental and theoretical data. We establish that the composition dependence of band gap is semi-metallic in B1 phase, while a direct band gap is observed in B3 phase. The calculated density of states is described by taking into account the contribution of Zn 3d, O 2p, and Se 4s, and the optical properties are studied in terms of dielectric functions, refractive index, reflectivity, and energy loss function for the B3 phase and are compared with the available experimental data. 相似文献
104.
105.
We study the order reduction method of the rotational relativistic Birkhoffian equations.For a rotational relativistic autonomous Birkhoffian system,if the conservative law of the Birkhoffian holds,the conservative quantity can be called the generalized energy integral.Through the eneralized energy integral,the order of the system can be reduced.If the rotational realtivistic Birkhoffian system has a generalized energy integral,then the Birkhoffian equations can be reduced by at least two degrees and the Birkhoffian form can be kept.An example is given to illustrate the application of the result. 相似文献
106.
《中国物理快报》2002,19(1):20-22
A new holographic entropy bound is obtained by using conformal field theory at the Killing horizon.The entropy bound is tighter than the well-known bounds,such as the Bekenstein,Bekenstein-Mayo and‘t Hooft bounds.The result shows that the entropy of a system decreases when quantum effects are included.Therefore,the quantum effect will increase the degree of order of the system. 相似文献
107.
108.
在入射电子能量 2 5 0 0eV下测量了He的 11S→ 2 1S ,2 1P ,31S和 31P的微分散射截面和广义振子强度 ,并与前人的实验和理论结果进行了比较 ,认为在此入射电子能量下一阶Born近似对此 4个跃迁成立. With electron impact energy of 2 500 eV and energy resolution of 85 meV, the differential cross sections and the generalized oscillator strengths of the excitations of 1 1S→2 1S, 2 1P, 3 1S and 3 1P of helium has been measured by electron energy loss spectroscopy . Comparing with previous experimental and theoretical results, it seems that the first Born approximation is valid for these excitations under such an electron impact energy. 相似文献
109.
110.
相位差与q变形广义相干叠加态的压缩特性 总被引:1,自引:0,他引:1
对于q变形的非简谐振子广义相干态的叠加态β〉+eiφβeiδ〉,其量子涨落的可能高阶压缩阶数可以表示为k≠2πn/δ,这里n是整数.当δ=π时,压缩阶数不能是偶数即只能是奇数,这正是q变形非简谐振子广义奇偶相干态的结果.由此表明参数相位差δ对决定q变形的非简谐振子广义相干态叠加态的高阶压缩阶数起决定性作用. 相似文献