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441.
O.G. Chorayan 《Fuzzy Sets and Systems》1982,8(2):141-147
The paper presents the results of investigation of the neuron of the frog visual analyzer central part and the crayfish 6th abdominal ganglion on the basis of fuzzy sets theory and some set-theoretical operations to establish the neuron membership in a particular ensemble in accordance with their essential characteristics. 相似文献
442.
FAN Hong-Yi 《理论物理通讯》2002,38(11)
We show that the Wigner function W = Tr(△ρ) (an ensemble average of the density operator ρ, △ is theWigner operator) can be expressed as a matrix element of ρ in the entangled pure states. In doing so, converting fromquantum master equations to time-evolution equation of the Wigner functions seems direct and concise. The entangledstates are defined in the enlarged Fock space with a fictitious freedom. 相似文献
443.
Karl W. Kratky 《Journal of statistical physics》1985,39(3-4):379-403
The equation of state of finite systems deviates from thermodynamic limit. The corresponding finiteness corrections of virial coefficients are studied. Most calculations are based on the canonical ensemble with periodic boundary conditions.Explicit andimplicit finiteness corrections occur. They are displayed up to the eighth virial coefficient. These results are applied to hard spheres in one, two, and three dimensions. 相似文献
444.
Hans-Otto Georgii 《Journal of statistical physics》1995,80(5-6):1341-1378
For systems of particles in classical phase space with standard Hamiltonian, we consider (spatially averaged) microcanonical Gibbs distributions in finite boxes. We show that infinite-volume limits along suitable subsequences exist and are grand canonical Gibbs measures. On the way, we establish a variational formula for the thermodynamic entropy density, as well as a variational characterization of grand canonical Gibbs measures. 相似文献
445.
Min Su Han 《Tetrahedron》2004,60(49):11251-11257
A sensing ensemble for cysteine was assembled conveniently by simply mixing N,N,N′,N′-tetra-(2-pyridylmethyl)-p-xylylenediamine (TPXD), cadmium perchlorate, and pyrocatechol violet in an 1:2:1 molar ratio in water of neutral pH. In the ensemble, [Cd2(TPXD)]4+ formed from TPXD and cadmium perchlorate serves as the receptor, and pyrocatechol violet functions as the indicator in sensing the analyte. The detection can be made either spectroscopically from the decrease of the UV-visible absorbance at 665 nm or visually from the color change to yellow upon addition of an aqueous solution of the analyte to the solution of the ensemble. The association constant (Kass) for the binding of the indicator to the receptor was determined with an isothermal titration calorimeter to be (2.77±0.98)×105 M−1 and that for the binding of cysteine to the receptor was obtained to have (1.62±0.97)×107 M−1 by the non-linear regression analysis of the titration curve obtained by titration of the solution of the ensemble with cysteine solution. The chemosensor showed excellent selectivity for cysteine over other amino acids including homocysteine. 相似文献
446.
Ikeguchi M 《Journal of computational chemistry》2004,25(4):529-541
A partial rigid-body method of molecular dynamics simulations for proteins and membranes is presented. In this method, the symplectic integrator for rigid bodies is combined with the equations of motion for the NPT ensemble. The standard NPT ensemble is extended to the membrane-specific ensembles, the NPAT (constant normal pressure and lateral surface area of membranes and constant temperature) and NPgammaT (constant normal pressure and lateral surface tension of membranes and constant temperature) ensembles. By more than 30-ns simulations of aqueous proteins and hydrated lipid bilayers, the results of the partial rigid-body method demonstrated excellent conservation of total energy and consistent behavior with the traditional constraint method in terms of structural distribution and fluctuation of proteins and lipids. The efficient implementation of the partial rigid-body method in parallel computation is presented, which is shown to work well in large-scale molecular dynamics simulations. 相似文献
447.
From analysis of numerous experimental data on grain boundary (GB) statistics in polycrystals it has been established that certain groups of materials with cubic structure reveal similar GB character distributions (GBCD) (distribution of GBs by reciprocal density of coincidence sites ). It has been shown that GBCD can be described with an empirical low with different parameters for various groups. Several criteria for classification of materials by these groups (the stacking fault energy value, hierarchy of GB energies and mechanism of replacement of high-energy GBs with low-energy ones) have been considered. It has been found that peculiarities of electronic structure of materials are correlated with the classification proposed. 相似文献
448.
In the Laguerre ensembleof n xN Hermitian matrices, it is of interest both theoretically and for applications to quantum transport problems to compute the variance of a linear statistic, denoted varN
f, asN . Furthermore, this statistic often contains an additional parameter a for which the limit is most interesting and most difficult to compute numerically. We derive exact expressions for both limN varN
f and lim , limN varN
f. 相似文献
449.
Christopher G. Jesudason 《Journal of mathematical chemistry》2007,42(4):893-908
The hysteresis dimer reaction of the first sequel is applied to test the Gibbs density-in-phase hypothesis for a canonical
distribution at equilibrium. The probability distribution of variously defined internal and external variables is probed using
the algorithms described, in particular the novel probing of the energy states of a labeled particle where it is found that
there is compliance with the Gibbs’ hypothesis for the stated equilibrium condition and where the probability data strongly
suggests that an extended equipartition principle may be formulated for some specific molecular coordinates, whose equipartition
temperature does not equal the mean system temperature and a conjecture concerning which coordinates may be suitable is provided.
Evidence of violations to the mesoscopic nonequilibrium thermodynamics (MNET) assumptions used without clear qualifications
for a canonical distribution for internal variables are described, and possible reasons outlined, where it is found that the
free dimer and atom particle kinetic energy distributions agree fully with Maxwell–Boltzmann statistics but the distribution
for the relative kinetic energy of bonded atoms does not. The principle of local equilibrium (PLE) commonly used in nonequilibrium
theories to model irreversible systems is investigated through NEMD simulation at extreme conditions of bond formation and
breakup at the reservoir ends in the presence of a temperature gradient, where for this study a simple and novel difference
equation algorithm to test the divergence theorem for mass conservation is utilized, where mass is found to be conserved from
the algorithm in the presence of flux currents, in contradiction to at least one aspect of PLE in the linear domain. It is
concluded therefore that this principle can be a good approximation at best, corroborating previous purely theoretical results
derived from the generalized Clausius Inequality, which proved that the PLE cannot be an exact principle for nonequilibrium
systems.
相似文献
450.
V. E. Gorin 《Functional Analysis and Its Applications》2008,42(3):180-197
We compute the bulk limit of the correlation functions for the uniform measure on lozenge tilings of a hexagon. The limiting determinantal process is a translation-invariant extension of the discrete sine process, which can also be described by an ergodic Gibbs measure with appropriate parameters. 相似文献