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91.
本文考察一类具耗散的广义KdV方程组■ (gradφ(■))_x ■_(xxx)-α■_(xx) γ■ =■(x,t,■)的周期初值问题的显式差分格式.利用有界延拓法证明了该差分格式的收敛性与稳定性,并给出了算法和数值例子. 相似文献
92.
含余割核奇异积分修改的反演问题 总被引:1,自引:0,他引:1
针对含余害核奇异积分反演问题在指κ<0时一般无解的情况,本文提出并求解两种修改的反演问题,而后一种修改反演问题的提法与此前类似问题颇不相同,由于运用了推广的留数定理和Bertrand型换序公式使本问题及类似问题解法得以简化。 相似文献
93.
Phase-Locked Fibre Array for Coherent Combination and Atmosphere Aberration Compensation 总被引:1,自引:0,他引:1 下载免费PDF全文
We report a fibre amplifier array that not only achieves coherent beam combination by compensation of phase noises of fibre amplifier, but also accomplishes correction of atmosphere aberration. It is of master-oscillatormultiple-amplifier (MOPA) configuration, which can be phase-locked by the multidither principle or heterodyne detection principle. First laboratory experiments of atmosphere aberration compensation of a three-element fibre amplifier array are reported. The atmosphere aberration is created by a phase screen in the experiment. The phase changes of the beam, which are introduced by the fibre amplifier and the phase screen, are both detected by the heterodyne detection method. Phase modulators are controlled to compensate for the phase in the three paths. No matter whether there is a phase screen producing atmosphere aberration or not, the dim dynamic interference fringes in the far field turn to a clear and stable pattern, and the peak intensity is maximized. It is indicated that the fibre amplifier array is phase-locked, and coherent combination of the three beams is achieved. It can be used not only to obtain high power fibre laser array but also in laser space communication. 相似文献
94.
FANG DAOYUAN GONG XIAOQING Department of Applied Mathematics Zhejiang University Hangzhou Department of Applied Mathematics Wuhan University of Hydraulic Electrical Engineering Wuhan 《高校应用数学学报(英文版)》1996,11(1):43-50
In this paper we study the Goursat problem for semilinear hyperbolicequations with zero boundary condition where the boundary is the characteristic conefor hyperbolic operator. Our result shows that the solution is Lipschitz and is smoothaway from the characteristic cone. 相似文献
95.
Yang Jing Wen Xiang Lin Yang 《International Journal of Infrared and Millimeter Waves》1998,19(7):963-975
The modified quantum nonlinear Schrodinger equation of ultra-short pulse propagating in fiber is derived using dispersion relation and the Hamiltonian of the transmission system. The derived equation is solved with linearization approximation, and modulation instability is analyzed. The equation is also solved with Hartree approximation. The results indicate that pulse power, loss and self-steeping effect change the critical frequency, the maximum gain and the gain spectrum range, but the third order dispersion has no effect on modulation instability. The expectation value of optical field is average of a set of modified classical solitons, and higher order terms change the amplitude, pulse position and phase of soliton. 相似文献
96.
97.
聚乙烯单晶的退火效应 总被引:1,自引:1,他引:1
用混合晶红外光谱法和SAXS、DSC和LAM等方法研究了聚乙烯单晶在75℃、90℃和105℃退火前后的结构变化,发现在90℃以下和105℃以上退火,遵循不同的退火机制 相似文献
98.
Jing Ping WANG Qiang WU Jing Yang NIU* School of Chemistry Chemical Engineering Henan University Kaifeng 《中国化学快报》2002,13(9):915-918
It is becoming a focus to synthesize and assemble organic-inorganic materials, especially, to synthesize charge-transfer complexes formed by polyoxometalate and organic donors. They have attracted much attention because such complexes are active in their electric, magnetic and optic properties1-4, many investigations about them have been done and some crystal structures of them were reported5-6. But, the disadvantage of these crystals is instability at room temperature. According to the view… 相似文献
99.
100.
A Cu(Ⅱ) complex [Cu(L)1.5(OSO3)]·3H2O (1) [L=1,4-bis(imidazol-1-yl)benzene] was synthesized by reaction of ligand L with CuSO4·5H2O using solvothermal method and its structure was determined by X-ray crystal structure analysis. The structure indicates that the complex crystallizes in triclinic, space group P1 with a=0.948 8(2), b=1.078 5(2), c=1.108 4(2) nm, α=74.820(2), β=81.331(2), γ=72.638(2)°, V=1.041 5(3) nm3, Z=2, Dcalc=1.687 g·cm-3, F(000)=544, μ=1.205 cm-1, the final R=0.062 3 and wR=0.132 8. The Cu(Ⅱ) atom has distorted square-pyramidal environment with a N3O2 donor set. Each L ligand links two Cu(Ⅱ) atoms using its imidazole groups to form an infinite one-dimensional (1D) ladder-like chain, which further linked by SO42- to form a two-dimensional (2D) network structure. The 2D sheets are further connected by C-H…O hydrogen bonds to give a three-dimensional (3D) structure. CCDC: 650388. 相似文献