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991.
应用群论及原子分子反应静力学方法推导了SiO2分子的电子态及其离解极限,采用B3P86方法,在6-311G**水平上,优化出SiO2基态分子稳定构型为单重态的C2V构型,其平衡核间距Re=RSi—O=0.1587 nm,∠OSiO=111.2°,能量为-440.4392 a.u..同时计算出基态的简正振动频率:对称伸缩振动频率ν(B2)=945.4cm-1,弯曲振动频率ν(A1)=273.5 cm-1和反对称伸缩振动频率ν(A1)=1362.9cm-1.在此基础上,使用多体项展式理论方法,导出了基态SiO2分子的全空间解析势能函数,该势能函数准确再现了SiO2(C2V)平衡结构. 相似文献
992.
本文列出了一维点阵非谐振动的非线性微分方程组,并求出了这组方程在相应边值条件下的解析解。据此算出了该点阵的热膨胀系数和热膨胀动态过程的特征时间,同时说明了它的物理意义。关于金属箔的实验结果,可以作为这一理论预言的一个验证。这些结果还告诉我们,在高速加热时,即使温度均匀而且膨胀自由,热应力仍然存在,不过将很快弛豫。 相似文献
993.
EXACT TRAVELING WAVE SOLUTIONS OF MODIFIED ZAKHAROV EQUATIONS FOR PLASMAS WITH A QUANTUM CORRECTION*
In this article,the authors study the exact traveling wave solutions of modified Zakharov equations for plasmas with a quantum correction by hyperbolic tangent function expansion method,hyperbolic seca... 相似文献
994.
995.
The nonadjacent form method of Koblitz [Advances in Cryptology (CRYPTO'98), in: Lecture Notes in Comput. Sci., vol. 1462, 1998, pp. 327–337] is an efficient algorithm for point multiplication on a family of supersingular curves over a finite field of characteristic 3. In this paper, a further discussion of the method is given. A window nonadjacent form method is proposed and its validity is proved. Efficient reduction and pre-computations are given. Analysis shows that more than 30% of saving can be achieved. 相似文献
996.
Xiao‐Yan Tu Ming‐Zhu Liu Hua Wei 《Journal of polymer science. Part A, Polymer chemistry》2016,54(11):1447-1458
Polymer topologies exert a significant effect on its properties, and polymer nanostructures with advanced architectures, such as cyclic polymers, star‐shaped polymers, and hyperbranched polymers, are a promising class of materials with advantages over conventional linear counterparts. Cyclic polymers, due to the lack of polymer chain ends, have displayed intriguing physical and chemical properties. Such uniqueness has drawn considerable attention over the past decade. The current review focuses on the recent progress in the design and development of cyclic polymer with an emphasis on its synthesis and bio‐related properties and applications. Two primary synthetic strategies towards cyclic polymers, that is, ring‐expansion polymerization and ring‐closure reaction are summarized. The bioproperties and biomedical applications of cyclic polymers are then highlighted. In the end, the future directions of this rapidly developing research field are discussed. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1447–1458 相似文献
997.
On the quasistatic effective elastic moduli for elastic waves in three-dimensional phononic crystals
Effective elastic moduli for 3D solid–solid phononic crystals of arbitrary anisotropy and oblique lattice structure are formulated analytically using the plane-wave expansion (PWE) method and the recently proposed monodromy-matrix (MM) method. The latter approach employs Fourier series in two dimensions with direct numerical integration along the third direction. As a result, the MM method converges much quicker to the exact moduli in comparison with the PWE as the number of Fourier coefficients increases. The MM method yields a more explicit formula than previous results, enabling a closed-form upper bound on the effective Christoffel tensor. The MM approach significantly improves the efficiency and accuracy of evaluating effective wave speeds for high-contrast composites and for configurations of closely spaced inclusions, as demonstrated by three-dimensional examples. 相似文献
998.
《合成通讯》2013,43(24):4339-4345
Abstract 1,3-Thiazin-4-ones 9 and 10 have been prepared from the corresponding isothiazolones 7 and 8 by a clean and smooth reaction with tertiary amines at room temperature. This rearrangement is attributed to the abstraction of a methine proton from the 2-position isothiazolone substituent, followed by ring enlargement through cleavage of the S-N bond. 相似文献
999.
In this study, experimental results are concerning “the optical bistability due to thermal lensing effect”, in colloidal solution of gold nanoparticles (Au Nps) which has been studied under CW laser illuminations. Two different CW laser beams (He–Ne and Nd-Yag) were used to interact with a vertical Fabry–Perot interferometer, containing colloid of the Au Nps. Hysteretic loops have been observed with regard to optical bistability and the results were fitted with theoretical curves. The radiated power to the resonator was elevated up to 50 mW for both the laser beams with the same spot size. Also, new method was defined to precise evaluation of the theoretical hysteretic loop which is describing the relation between nonlinear refractive index and the beam intensity inside the resonator. This dependency is due to thermal lensing effect and numerical simulations of this effect were also performed, in order to better understanding of it. 相似文献
1000.