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51.
本文用边界元法研究非均质无限域弹性薄板弯曲问题.在数值实施过程中,对于夹杂和基体分别形成边界积分方程.通过离散边界积分方程,得到相应的方程组,然后结合界面条件,最终获得问题的求解方程组.在界面的相关量求得之后,可以根据需要来求解基体和夹杂中的有关位置的弯矩.数值结果与已有的解做了对比. 相似文献
52.
本文引入一类广义增生算子——强(A,η)-增生算子.定义强(A,η)-增生算子的广义预解算子并证明它的Lipschitz连续性,进一步证明含强(A,η)-增生算子的变分包含的一些新的迭代算法的收敛性.所得结果改进和推广了许多文献的相应结果. 相似文献
53.
Xing-Hua ZhuJian-Zhong Xiao 《Applied mathematics and computation》2011,217(12):6004-6010
A new continuity theorem of minimum selection is presented for a continuous set-valued operator from a topological space into a Banach space with some uniform convexity. As applications, some problems concerning minimum right inverses for linear operators and minimum fixed points for condensing set-valued nonlinear operators are discussed. Also, the existence of minimum solutions for an integral inclusion is proved. 相似文献
54.
55.
熔石英亚表面缺陷是光学材料低损伤阈值的主要因素之一.本文建立了熔石英亚表面三维球形杂质颗粒模型,采用三维时域有限差分方法对杂质附近的光场进行了数值模拟,分析了杂质的介电常数与尺寸对光强增强因子的影响,结果显示:介电常数小于熔石英的杂质,其光强增强因子不随尺寸、介电常数的改变而改变,均保持为4左右;当介电常数为6.0时,半径为1.5λ,2λ及2.5λ的杂质,相应的光强增强因子分别为50.1588,73.3904及102.9953,即增强因子随杂质尺寸的增大而增大;恰
关键词:
杂质颗粒
三维时域有限差分
数值计算
光强增强因子 相似文献
56.
Robust Inclusion Complexes of Crown Ether Fused Tetrathiafulvalenes with Li+@C60 to Afford Efficient Photodriven Charge Separation 下载免费PDF全文
Dr. Mustafa Supur Yuki Kawashima Dr. Karina R. Larsen Dr. Kei Ohkubo Prof. Jan O. Jeppesen Prof. Shunichi Fukuzumi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(43):13976-13983
Inclusion complexes of benzo‐ and dithiabenzo‐crown ether functionalized monopyrrolotetrathiafulvalene (MPTTF) molecules were formed with Li+@C60 ( 1? Li+@C60 and 2? Li+@C60). The strong complexation has been quantified by high binding constants that exceed 106 M ?1 obtained by UV/Vis titrations in benzonitrile (PhCN) at room temperature. On the basis of DFT studies at the B3LYP/6‐311G(d,p) level, the orbital interactions between the crown ether moieties and the π surface of the fullerene together with the endohedral Li+ have a crucial role in robust complex formation. Interestingly, complexation of Li+@C60 with crown ethers accelerates the intersystem crossing upon photoexcitation of the complex, thereby yielding 3(Li+@C60)*, when no charge separation by means of 1Li+@C60* occurs. Photoinduced charge separation by means of 3Li+@C60* with lifetimes of 135 and 120 μs for 1? Li+@C60 and 2? Li+@C60, respectively, and quantum yields of 0.82 in PhCN have been observed by utilizing time‐resolved transient absorption spectroscopy and then confirmed by electron paramagnetic resonance measurements at 4 K. The difference in crown ether structures affects the binding constant and the rates of photoinduced electron‐transfer events in the corresponding complex. 相似文献
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58.
A heavy and hard peak-shaped inclusion in an elastic body provokes to concentration of eigenvalues in the low-frequency range of the spectrum and localization of the corresponding eigenmodes near the peak tip. To cite this article: S.A. Nazarov, C. R. Mecanique 335 (2007). 相似文献
59.
A general method based on complex variable theory is proposed to determine the magnetic and elastic fields of a piezomagnetic
body. This method is used to derive the basic relations for complex potentials in the two-dimensional problem of magnetoelasticity,
their general representations for a multiply connected domain, expressions for stresses, displacements, vectors of magnetic
field intensity and magnetic flux density, and magnetic field potential. A closed-form solution is obtained for a body with
an elliptic (circular) hole or crack subjected at infinity to the action of a constant magnetoelastic field. Numerical results
for a piezomagnetic plate with a circular hole are presented
__________
Translated from Prikladnaya Mekhanika, Vol. 41, No. 10, pp. 64–74, October 2005. 相似文献
60.
V. I. Kushch 《International Applied Mechanics》2004,40(8):893-899
An elastic-equilibrium problem is rigorously solved for a transversely isotropic body containing a finite number of arbitrarily arranged and oriented transversely isotropic spherical inclusions or an infinite periodic array of such inclusions. The solution is found based on the superposition principle for general solutions of single-particle problems and the addition theorems for partial vector solutions of the elastic equilibrium equations. The numerical results presented allow assessing the influence of matrix anisotropy on the stress concentration between inclusions 相似文献