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41.
Vladimir D. Maiorov Irina S. Kislina Alexey A. Rykounov Mikhail V. Vener 《Journal of Physical Organic Chemistry》2014,27(2):135-141
The infrared (IR) spectra of water–ethanol (EtOH) solutions of HCl are measured over a wide range of acid concentration at fixed H2O―EtOH ratios (1 : 1, 1 : 2, and 1 : 40). In these systems, different proton disolvates with (quasi)symmetrical H‐bonds are formed. Their structure and vibrational features are revealed by the density functional theory method coupled with the polarizable continuum model of solvation. In dilute acidic solutions, the Zundel‐type H5O2+ ion is mainly formed. In concentrated HCl solutions, the ions (H2O···H···O(H)Et)+ and (Et(H)O···H···O(H)Et)+ with the quasi‐symmetrical O···H+···O unit having O···O separation <2.45 Å appear. The first ion characterized by the IR‐intensive band around 1800 cm?1 is mainly formed in the 1 : 1 water–ethanol systems. The second ion exists in the 1 : 2 and 1 : 40 water–ethanol systems. Its spectroscopic signatures are the groups of the IR‐intensive bands around 800 and 1050 cm?1. In highly concentrated HCl solutions with the 1 : 40 water–ethanol ratio, a neutral Et(H)O···H+···Cl? complex exists. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
42.
《Physics and Chemistry of Liquids》2012,50(2):157-165
In the Thomas–Fermi (TF) regime, S. Stringari [Phys. Rev. Lett., 77, 2360 (1996)] established the hydrodynamic normal modes of an interacting dilute Bose-condensed fluid confined in an isotropic harmonic trap. Here, we extend this treatment beyond the TF condensate using the work of B. Hu, G. Huang and Y. Ma [Phys. Rev. A, 69, 063608 (2004)] as a starting point. Both numerical results for low-lying eigenfrequencies, for various angular momentum quantum numbers???and n?=?0, and also samples of corresponding eigenfunctions, are presented. Finally, eigenfrequencies are also given for some collective excitations in an axially symmetrical trap. 相似文献
43.
44.
Investigation of the limit of lateral beam shifts on a symmetrical metal-cladding waveguide
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This paper reports that Goos--H\"anchen (GH) shifts
occurring on a symmetrical metal-cladding waveguide are
experimentally identified. It was found that there exists a critical
thickness of the upper metal layer, h_cr, above which negative
shift is observed and, reversely, positive shift occurs. Both
positive and negative GH shifts near the critical thickness do not vary
dramatically and can achieve a maximum on the submillimeter scale, which
is different from simulated results using the stationary-phase
method. It also shows that this critical thickness, h_cr, can be
obtained at the position for zero reflectivity by setting the
intrinsic damping to be the same as the radiative damping. The GH
effects observed near the critical thickness are produced by extreme
distortion of the reflected beam profiles, which limits the
amplitude of the GH shift and, further, the sensitivity of the GH optical
sensor based on the symmetrical metal-cladding waveguide. 相似文献
45.
含有大位移动边界的复杂流场的数值模拟 总被引:1,自引:1,他引:0
含有运动弹丸的膛口流场是典型的大位移动边界问题,同时弹丸在出膛过程中,流场的结构也会发生变化,增加了流场的复杂程度.在对该流场的数值模拟中,将它分为两个区:弹丸运动区和普通流场区,它们之间用一个特殊的分区边界联系,同时运用网格局部重构技术处理弹丸运动造成的网格变形问题,并将对称轴定义为网格变形边界,使得弹丸在对称轴上运动过程中不会导致对称轴上的网格体积为负.从计算结果可以看出整个膛口波系结构变化过程和弹丸先加速后减速的过程,从而表明该动网格处理方法是成功的. 相似文献
46.
47.
48.
The collective variables method with a reference system is developed for the case of the grand canonical ensemble for a multicomponent continuous system. The method is used to investigate phase transitions in a binary system. For a binary symmetrical system the relations between microscopic parameters determining the alternation of gas-liquid and separation phase transitions are found. The functional of the grand partition function of the symmetrical mixture is examined in the framework of parameters containing the separation point. The system is described with two sets of collective variables: k, a set connected with the gas-liquid critical point, andc
k, a set connected with the separation phenomenon. The fourfold basic density measure is constructed inc
k-variable phase space which contains the variablec
v
connected with the order parameter of the system. It is shown that the problem can be reduced to the 3D Ising model in an external field. 相似文献
49.
Li Shirong 《代数通讯》2013,41(6):1913-1918
In this paper, the minimal subgroups of a finite group G are studied. Using the normalizes of Sylow subgroups of G, we obtain some sufficient conditions for G to be p-milpotent and supersolvable, which ae extensions of the related results of Burnside, Ito, Buckley and Asaad. 相似文献
50.