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941.
The interaction of comenic acid with cetylpyridinium chloride in aqueous solutions was studied by spectrophotometry. Compositions of ionic associates formed depending on cetylpyridinum chloride concentration were found, and logarithms of equilibrium constants of corresponding association reactions were determined. 相似文献
942.
J.-P. Blaizot E. Iancu A. Rebhan 《The European Physical Journal C - Particles and Fields》2003,27(3):433-438
We compare our previously proposed hard-thermal-loop (HTL) resummed calculation of quark number susceptibilities using a
self-consistent two-loop approximation to the quark density with a recent calculation of the same quantity at the one-loop
level in a variant of HTL-screened perturbation theory. Besides pointing out conceptual problems with the latter approach,
we show that it severely over-includes the leading-order interaction effects, while including none of the plasmon terms, which
is the main reason for requiring improved resummation schemes.
Received: 27 June 2002 / Revised version: 23 September 2002 / Published online: 31 January 2003 相似文献
943.
Y. V. Bludov A. J. Kirichenko A. E. Kogut V. V. Kutuzov V. A. Solodovnik 《Radiophysics and Quantum Electronics》2005,48(12):927-933
We experimentally study a new type of resonator, namely, a barrel-shaped dielectric resonator with whispering-gallery modes
which is formed by the cutting dielectric hemisphere. Compared with a hemispherical dielectric resonator, the E type oscillation
spectrum of such a resonator is rarefied with respect to the azimuthal index. Comparative analysis of the electromagnetic
characteristics of the barrel-shaped dielectric resonator and half-disk dielectric resonators shows that the radiation losses
of the mode energy from the spherical surface are smaller than those from the cylindrical surface. This fact stimulates the
high values of the internal Q-factor of modes of the barrel-shaped dielectric resonator.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 48, No. 12, pp. 1041–1048, December 2005. 相似文献
944.
945.
E.J. Avital 《Journal of sound and vibration》2004,270(3):483-494
A new Dispersion-Relation-Preserving (DRP) scheme has been developed using the Lax-Wendroff methodology. Two collocated grids are placed in a staggered formation and a staggered DRP scheme is used to calculate the spatial differentiation of the propagation and convection terms. A staggered filtering scheme of a six points stencil is developed to complete the transformation from one grid to another. Existing DRP Runge-Kutta schemes are used for the time marching. Stability limits and accuracy issues are investigated using a simple 1D advection equation. The new method is then tested for monopole and quadrupole radiation, diffraction effects of an aperture in a wall, and convection effects of shear flow. All demonstrate the good accuracy and numerical stability of the new method. 相似文献
946.
E. D. Tymchatyn M. Zarichnyi 《Proceedings of the American Mathematical Society》2004,132(9):2799-2807
We consider the question of simultaneous extension of (pseudo) metrics defined on nonempty closed subsets of a compact metrizable space. The main result is a counterpart of the result due to Künzi and Shapiro for the case of extension operators of partial continuous functions and includes, as a special case, Banakh's theorem on linear regular operators extending (pseudo)metrics.
947.
L. A. Lapkina Yu. G. Gorbunova S. E. Nefedov A. Yu. Tsivadze 《Russian Chemical Bulletin》2003,52(7):1633-1636
948.
The transformation of a shear surface magnetoelastic wave by the motion of the 180° confining domain wall in a ferromagnet is considered. Changes in the wave spectrum due to the motion of the wall are correlated with the variations of the energies of the elastic and magnetic subsystems. The efficiency of surface wave transformation by the domain wall motion is estimated in terms of energy. The frequency dependences of the mean energy density of the wave are found. It is shown that the energy density grows with wall velocity. 相似文献
949.
950.
In this paper we describe the experimental analysis of a novel ion-exchange polymer metal composite (IPMC) actuator under
large external voltage. The experimental analysis is supplemented with a coupled thermodynamic model, which includes mass
transport across the thickness of the polymer actuator, chemical reactions at boundaries, and deformation as a function of
the solvent (water) distribution. In this paper, the case of large electrode potentials (over 1.2 V) has been analyzed experimentally
and theoretically. At these voltage levels, electrochemical reactions take place at both electrodes. These are used in the
framework of overpotential theory to develop boundary conditions for the water transport in the bulk of polymer. The model
is then simplified to a three-component system comprised of a fixed negatively charged polymeric matrix, protons, and free
water molecules within the polymer matrix. Among these species, water molecules are considered to be the dominant species
responsible for the deformation of the IPMC actuators. Experiments conducted at different initial water contents are described
and discussed in the context of the proposed deformation mechanism. Comparison of numerical simulations with experimental
data shows good agreement. 相似文献