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51.
K. P. Meletov V. K. Dolganov Yu. A. Ossipyan 《Molecular Crystals and Liquid Crystals》2013,570(1):915-920
Abstract The absorption spectra of the C60 and C70 are measured at pressures up to 19 GPa. The pressure dependence of the fundamental absorption edge position E(P) is determined for both materials. The initial value of dE/dP=?0.15 eV/GPa for the stronger-absorption region of C60 decreases up to ?0.019 eV/GPa at 12 GPa. The weaker-absorption region located near the fundamental absorption edge shifts slower dE/dP=?0.05 eV/GPa. For the C70 the initial value of dE/dP=?0.1 eV/GPa decreases up to ?0.029 eV/GPa at 10 GPa. All pressure induced changes are reversible in this pressure range. 相似文献
52.
HAN Guo-qiang YA O Hai-lou 《数学季刊》2014,(2):244-246
Let K be an algebraically closed field and A be a finite dimensional algebra over K. In this paper we give a classification of biserial incidence algebras with quiver methods. 相似文献
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A.YA. Dorofeev L.S. Kazarin V.M. Sidelnikov M.E. Tuzhilin 《Designs, Codes and Cryptography》2005,37(3):391-404
We consider a finite matrix group
with 34· 216 elements, which is a subgroup of the infinite group
, where
is the regular representation of the quaternion group and C is a matrix that transforms the regular representation Q to its cellwise-diagonal form. There is a number of ways to define the matrix C. Our aim is to make the group
similar in a certain sense to a finite group. The eventual choice of an appropriate matrix C done heuristically.
We study the structure of the group
and use this group to construct spherical orbit codes on the unit Euclidean sphere in R8. These codes have code distance less than 1. One of them has 32· 28 = 2304 elements and its squared Euclidean code distance is 0.293.
Communicated by: V. A. Zinoviev 相似文献
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用相对论有效原子实势 (RECP)和密度泛函 (B3LYP SDD)方法研究了UH ,UH2 基态和低激发态的结构和势能函数 ,导出了分子的光谱数据 .结果表明 ,UH和UH2 的基电子状态分别为X4 Π和X3A2 ,离解能分别为 2 .886eV和5 .2 4 9eV ,UH2 具有C2v对称性 ,得到了UH和UH2 的几个不同的低激发态的结构与光谱数据 .应用多体项展式理论以及数字拟合方法 ,计算得到了UH分子和基态UH2 三原子分子的分析势能函数 ,该函数正确反映了UH和UH2分子的结构特征 ,可用于研究UHH的微观反应动力学 . 相似文献
59.
Fin materials can be observed in a variety of engineering applications. They are used to ease the dissipation of heat from a heated wall to the surrounding environment. In this work, we consider a nonlinear fin problem with temperature-dependent thermal conductivity and heat transfer coefficient. The equation(s) under study are highly nonlinear. Both the thermal conductivity and the heat transfer coefficient are given as arbitrary functions of temperature. Firstly, we consider the Lie group analysis for different cases of thermal conductivity and the heat transfer coefficients. These classifications are obtained from the Lie group analysis. Then, the first integrals of the nonlinear straight fin problem are constructed by three methods, namely, Noether’s classical method, partial Noether approach and Ibragimov’s nonlocal conservation method. Some exact analytical solutions are also constructed. The obtained result is also compared with the result obtained by other methods. 相似文献
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