The simplified expression of the Pozhar-Gubbins (PG) rigorous, nonequilibrium statistical mechanical theory of dense, strongly inhomogeneous fluids is used to calculate the viscosity of model fluids confined in a slit pore of several molecular diameters in width in terms of the equilibrium structure factors (i.e., the number density and pair correlation functions) of these nanofluids obtained by means of the equilibrium molecular dynamic simulations. These results are compared to those obtained by means of the nonequilibrium molecular dynamic simulations of the planar Poiseuille flow of the model nanofluids, and to the results supplied by several heuristic expressions for the nanofluid viscosity. This comparison proves that the PG transport theory provides a reliable, quantitatively accurate description of the viscosity coefficients of the model nanofluids while all the heauristic approaches fail. This success of the PG prediction of the nanofluid viscosity is because the theoretical expression accounts accurately for the nanofluid structure.

The generalized Enskog-like kinetic equation (GEKE) derived recently for inhomogeneous fluids [L. A. Pozhar and K. E. Gubbins, J. Chem. Phys. 94, 1367 (1991)] has been solved using the thirteen-moments approximation method to obtain linearized Navier-Stokes equations and the associated zero-frequency transport coefficients. Simplified transport coefficient expressions have been obtained for several special cases (simplified geometries, homogeneous fluid). For these cases it is shown that the main contributions to the transport coefficients can be related to those for dense homogeneous fluids calculated at "smoothed" number densities and pair correlation functions. The smoothing procedure has been derived rigorously and shown to be an intrinsic feature of the GEKE approach. These results have been established for an arbitrary dense inhomogeneous fluid with intermolecular interactions represented by a sum of hard-core repUlsive and soft attractive potentials in an arbitrary external potential field and/or near structured solid surfaces of arbitrary geometries.

Exchange bias (EB) phenomena have been observed in Nd 2/3 Ca 1/3 MnO 3 colossal magnetoresistance perovskite below the Curie temperature T C ~ 70 K and attributed to an antiferromagnetic (AFM) -ferromagnetic (FM) spontaneous phase segregated state of this compound. Field cooled magnetic hysteresis loops exhibit shifts toward negative direction of the magnetic field axis. The values of exchange field H EB and coercivity H C are found to be strongly dependent of temperature and strength of the cooling magnetic field H cool . These effects are attributed to evolution of the FM phase content and a size of FM clusters. A contribution to the total magnetization of the system due to the FM phase has been evaluated. The exchange bias effect decreases with increasing temperature up to T C and vanishes above this temperature with disappearance of FM phase.Relaxation of a non-equilibrium magnetic state of the compound manifests itself through a training effect also observed while studying EB in Nd 2/3 Ca 1/3 MnO 3 .

The theory of transport in highly inhomogeneous systems, developed recently by Pozhar and Gubbins, and the nonequilibrium molecular dynamics ͑NEMD͒ technique are employed to study the viscosity of WCA fluids confined in narrow slit pores of width 5.1 and 20 at reduced densities 3 of 0.422-0.713. Calculated quantities include the equilibrium and nonequilibrium density profiles, equilibrium pair correlation functions, flow velocity profiles, and the viscosity profiles. NEMD simulation results are compared with the theoretical predictions. The agreement is good except for the region within one molecular diameter from the walls. The viscosity was found to vary with position across the pore.

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