ISSN:0005-9021    

DOI:10.1002/bbpc.19900940302

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940303

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

摘要:

AbstractThe interrelation between the flow properties of fluids and the shear‐induced changes of their structure is discussed and the methods for their study are reviewed. The fruitful interaction between (conventional) theory, simulation, experiment and application is emphasized. Results are presented for simple fluids where the distortion of the local (short range) order, as described by the pair‐correlation function or the static structure factor, is found to be in good agreement with kinetic theory predictions. Experimental data are compared with results of nonequilibrium molecular dynamics (NEMD) computer simulations which are also used to study the non‐newtonian flow behavior of simple fluids. The spectacular long range positional order found in NEMD simulations at high shear rates is reviewed and interpreted as a hydrodynamic instab

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940304

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

摘要:

AbstractWe give a brief review of the theory of sedimentation in suspensions. Ensemble averaging is used to obtain equations relating the average velocity of the scattering particles to the average suspension velocity and the applied forces. A theoretical difficulty due to the long range of the hydrodynamic interactions is overcome by a proper formulation of the constitutive equations on the macroscopic level.

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940305

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

摘要:

AbstractWhen suspended in a liquid, hard spherical colloidal particles can show fluid, crytalline and glassy phases. A light scattering study of the dynamics of the metastable fluid and glassy phases is reported. Comparison is made with the predictions of mode‐coupling theories applied to the glass transition of simple atomic system

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940306

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

摘要:

AbstractParticle transport in pores bounded by a pair of parallel, semi‐infinite absorbing boundaries, ideally permeable to the suspending medium, is studied theoretically by solving the classical convective‐diffusive transport equation both for the first passage times and for the particle number versus time profiles. The initial transient appearing in the profiles is ascribed to the initial condition specifying the particle distribution in the pore before the onset of transport and absorption. At small convective flows, the post‐transient period in the profile is characterised by first‐order kinetics, but at large flow rates this period splits into two distinct regimes, one exhibiting zero‐order and the other first‐order kinetic behaviour. The rate constants obtained from the profiles are compared with those derived from the first pa

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940307

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

摘要:

AbstractA quantum mechanical mechanism causing high ionic conductances in condensed phases is revealed through the application of the Complex Scaling Method into the statistical mechanics of amorphous condensed matter. It is argued that the predicted high conductivities are due to quantum delocalization of the considered ions, which causes their mass interference with the equivalent particles (ions, atoms) in their surroundings. The physical contexts (i) of the H+and OH−conductivity in aqueous solutions, and (ii) of the ionic conductivity in molten alkali chlorides are considered explicitly. A common mechanism for the well known high conductivities in these systems is presented. Direct connection with existing experimental data is made. A proposed experiment to test the theory is mentioned, and first experimental results verifying the theory are presente

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940308

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

摘要:

AbstractWe present the results of a computer simulation of the dynamics of a hard sphere suspension without hydrodynamic interactions that was performed using an algorithm recently developed by the authors. The dynamical structure factors and the mean‐square displacement have been calculated for various volume fractions between 0.1 and 0.5. Is is shown that the temporal behaviour of the time derivative of the mean‐square displacement is very well described by the stretched exponential function exp(‐const.√t). It is also shown that the results for the dynamical structure factors almost perfectly agree with those of a theory combining in the proper way the Enskog term with the mode‐mode coup

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940309

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

摘要:

AbstractWe give a brief outline of the theory and algorithms used in performing nonequilibrium molecular dynamics simulations of the properties of liquids undergoing planar Couette flow. We then give a very brief account of some of the results that can be performed using this type of calculation.

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940310

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY

摘要:

AbstractThe thermodynamic irreversibility of molecular processes involving heat transfer is established by incorporating time‐reversible dynamical thermostats in the equations of motion. It is then possible to understand why nonequilibrium steady statesmustobey the Second Law of Thermodynamics, not just with high probability, butwith probability one.This is because nonequilibrium states are sorare, relative to equilibrium ones, as to occupy a zero‐volume multifractal part of equilibrium phase space. These conclusions are generally valid. We illustrate them here by studying equilibrium manybody systems, both solid and fluid, as well as a simple one‐body chaotic nonequilibrium steady state. In all these cases we follow the motion of an orthonormal set of comoving vectors {δ}, determining the time‐averaged “Lyapunov Spectrum” of dynamic instability rates, as well as the vectors “Rotation Spectrum”, and relating these spectra to the irreversible nature of nonequilibrium flows

ISSN:0005-9021    

DOI:10.1002/bbpc.19900940311

出版商:Wiley‐VCH Verlag GmbH&Co. KGaA    

年代:1990

数据来源: WILEY