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81.
In this study, two-center overlap integrals over Slater-type orbitals (STOs) with integer and noninteger principal quantum numbers in unaligned coordinate systems have been calculated using formulas for overlap integrals in aligned coordinate systems obtained by the author's previous work (T. Ozdogan and M. Orbay, Int. J. Quant. Chem. 87(2002) 15). The obtained results for integer case have been found to be in excellent agreement with the prior literature.On the other hand, to the best of authors knowledge, because of the scarcity of the literatures on the use of noninteger n-STOs in unaligned coordinate systems, the results for noninteger case have been tested with the limit of integer case,and good agreement has been obtained too. 相似文献
82.
Frank E. Harris 《Pramana》2003,61(4):C779-C780
Guseinov, Mamedov, Kara and Orbay (Pramana - J. Phys.
56, 691 (2001)) propose methods for evaluating the molecular auxiliary functionsA
n(p) andB
n(pt) for the range 17 ≤n ≤ 60 and 25 ≤pt ≤ 60. However, their procedure forA
n(p) is not new, and that forB
n(pt) is less efficient for their target range than another well-known method. Their approach does have merit for smaller non-zero
values ofpt. Two minor errors in table 1 of their paper are also identified. 相似文献
83.
Saba Mirza Priti Singh Rajesh Kumar A.L. Vyas Chandra Shakher 《Optics and Lasers in Engineering》2006,44(1):41-55
New filtering scheme is investigated and implemented on digital speckle pattern interferometric fringes to enhance the signal-to-noise ratio (SNR) in the speckle interferograms. To establish the potential of new filtering scheme the experiment was conducted on the vibrating cantilever beam. Experimental results revealed that the new filtering scheme is more powerful than other known filtering schemes (Kumar et al. Opt Laser Eng 2004;41:81–93. Kumar et al. Opt Laser Technol 2001;33:567–571. Shakher et al. Opt Eng 2002;41:176–180. Shakher et al. Proceedings ICICS, Singapore, 9–12 September 1997, p. 953–956. Bowler et al. Proceedings of IEE second international conference on image processing, London, 1986, p. 24–26. Lim. Opt Eng 1981;20:670–678. Devila et al. J Mod Opt 1995;42:1795–1804; Kaufmann et al. Opt Eng 1996;35:9–14). The new scheme reduced the speckle noise and improved SNR in speckle interferograms. Further, the new investigated filtering scheme is implemented to study the mode shapes of square plates under two different boundary conditions. In the first condition all the edges of the square plate were fixed while in the second condition two adjacent edges were fixed and the remaining two edges were free. From the experimental results it is clear that the mode shapes are more distinctly visible with the implementation of the new filtering scheme as compared to other known schemes. Under both the boundary conditions the recorded resonance frequencies were compared with the calculated values of resonance frequencies based on classical theory. The results obtained form DSPI show good agreement with classical theory. 相似文献
84.
A perturbation theory of polar hard Gaussian overlap fluid mixture is discussed. Explicit analytic expressions for the second
and third varial coefficients are given. Numerical results are estimated for the thermodynamic properties of quadrupolar hard
Gaussian overlap fluid and fluid mixture. It is found that the excess free energy and internal energy depend on concentrationsc
1,c
2, molecular diameter ratioR, shape parameterK and the quadrupole momentsQ*1,Q*2. 相似文献
85.
86.
87.
Densities (ρ) of glycine, L-alanine, and L-valine in aqueous solutions of MgCl2-6H2O (0.1-0.8 mol kg-1) have been measured at 288.15, and 308.15 K. Apparent molar volumes (V
φ), and limiting partial molar volumes (V
φ
0
) of each amino acid have been calculated. These data were combined with the earlier reportedV
φ
0
values of glycine, L-alanine, and L-valine in aqueous MgCl2·6H2O solutions at 298.15 K in order to describe the temperature dependence behaviour of partial molar quantities. Group contributions
to partial molar volumes have been determined for the amino acids. The trends of transfer volumes (△V
φ
0
) have been interpreted in terms of solute-cosolute interactions on the basis of a cosphere overlap model. Pair and triplet
interaction coefficients have also been calculated from transfer parameters. 相似文献
88.
LiNbO3质子交换波导及其退火效应 总被引:3,自引:0,他引:3
采用质子交换技术,以苯甲酸为交换源,实验研究X-切LiNbO3质子交换平面波导及其退火效应。利用棱镜耦合器测出波导模折射率。采用费米函数,由模折射率确定出波导折射率分布随退火时间的变化关系,给出了分布参数和曲线. 相似文献
89.
多孔径扫描波面恢复技术的精度评定及影响因素 总被引:9,自引:2,他引:7
多孔径扫描波面恢复技术是一项新的高精度大孔径面形检测手段.本文从建立波面恢复精度的评价标准出发,结合实测结果进行讨论,并对影响精度的两个重要因素即拼接模式及拼接区大小进行分析. 相似文献
90.