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871.
Hans Christian Öttinger 《ournal of non Newtonian Fluid Mechanics》2010,165(17-18):1005-1013
Poisson brackets provide the mathematical structure required to identify the reversible contribution to dynamic phenomena in nonequilibrium thermodynamics. This mathematical structure is deeply linked to Lie groups and their Lie algebras. From the characterization of all the Lie groups associated with a given Lie algebra as quotients of a universal covering group, we obtain a natural classification of rheological models based on the concept of discrete reference states and, in particular, we find a clear-cut and deep distinction between viscoplasticity and viscoelasticity. The abstract ideas are illustrated by a naive toy model of crystal viscoplasticity, but similar kinetic models are also used for modeling the viscoplastic behavior of glasses. We discuss some implications for coarse graining and statistical mechanics. 相似文献
872.
Wolfgang Scherer Prof. Dr. Christoph Hauf Dipl.‐Phys. Manuel Presnitz Dipl.‐Phys. Ernst‐Wilhelm Scheidt Dr. Georg Eickerling Dr. Volker Eyert Dr. Rolf‐Dieter Hoffmann Dr. Ute C. Rodewald Dipl.‐Ing. Adrienne Hammerschmidt Dr. Christian Vogt Dr. Rainer Pöttgen Prof. Dr. 《Angewandte Chemie (International ed. in English)》2010,49(9):1578-1582
873.
This article is the first in a series dealing with the thermodynamic properties of quantum Coulomb systems.In this first part, we consider a general real-valued function E defined on all bounded open sets of R3. Our aim is to give sufficient conditions such that E has a thermodynamic limit. This means that the limit E(Ωn)|Ωn|−1 exists for all ‘regular enough’ sequence Ωn with growing volume, |Ωn|→∞, and is independent of the considered sequence.The sufficient conditions presented in our work all have a clear physical interpretation. In the next paper, we show that the free energies of many different quantum Coulomb systems satisfy these assumptions, hence have a thermodynamic limit. 相似文献
874.
C. Yohannan Panicker Hema Tresa Varghese K. Madhusoodanan Pillai Y. Sheena Mary K. Raju T.K. Manojkumar Anna Bielenica Christian Van Alsenoy 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(5):1559-1565
Fourier-transform-Raman and infrared spectrum of 4-azatricyclo [5.2.2.02,6] undecane-3,5,8-trione were recorded and analyzed. The vibrational wavenumbers were examined theoretically using the Gaussian03 set of quantum chemistry codes, and the normal modes were assigned by potential energy distribution (PED) calculations. The first hyperpolarizability, predicted infrared intensities and Raman activities are reported. The calculated first hyperpolarizability is comparable with reported values of similar structures which makes this compound an attractive object for future studies of nonlinear optics. Optimized geometrical parameters of the compound are in agreement with similar reported structures. The red shift of the NH stretching wavenumber in the infrared spectrum from the computational wavenumber indicates the weakening of NH bond. 相似文献
875.
876.
In this article we answer a question proposed by Gelfond in 1968. We prove that the sum of digits of squares written in a
basis q ⩾ 2 is equidistributed in arithmetic progressions. 相似文献
877.
878.
879.
880.
The set of doubly-stochastic quantum channels and its subset of mixtures of unitaries are investigated. We provide a detailed
analysis of their structure together with computable criteria for the separation of the two sets. When applied to O(d)-covariant channels this leads to a complete characterization and reveals a remarkable feature: instances of channels which
are not in the convex hull of unitaries can become elements of this set by either taking two copies of them or supplementing
with a completely depolarizing channel. These scenarios imply that a channel whose noise initially resists any environment-assisted
attempt of correction can become perfectly correctable. 相似文献