@article {1469,
	title = {Surface characterization of polytetrafluoroethylene (PTFE) transfer films during rolling-sliding tribology tests using X-ray photoelectron spectroscopy},
	journal = {Wear},
	volume = {261},
	number = {10},
	year = {2006},
	note = {ISI Document Delivery No.: 113XZTimes Cited: 4Cited Reference Count: 33Lu, X. Wong, K. C. Wong, P. C. Mitchell, K. A. R. Cotter, J. Eadie, D. T.},
	month = {Nov},
	pages = {1155-1162},
	type = {Article},
	abstract = {A disk-on-disk Amsler wear tester simulating the rolling-sliding motion and high pressure during wheel/rail contact, was used to study the wear performance of PTFE including its film transfer and material flow properties. The chemical composition of the transfer film formed on the wheel-disk surface at various test stages were analyzed by X-ray photoelectron spectroscopy (XPS). The friction curve of the PTFE films obtained on the Amsler can be divided into three regions, according to the friction level and disk surface morphology. Initially, there is a rapid increase of friction coefficient which is presumably accompanied by a fast material transfer from pre-coated rail-disk to the wheel-disk surfaces. In the second region, the friction remains stable throughout and the XPS results show the presence of PTFE on the wheel-disk surface which confirms a transfer of material between the two contact surfaces. In addition, the splitting of F 1s and C 1s photoelectron peaks of PTFE, as a result of a discrepancy in surface charging, suggests that the transfer film exists in two forms: thick patch and thin film. With an increase in rolling cycles, the thick patches become thinner, as well as its coverage reduces. By contrast, the thin film gains both in thickness and coverage. Using a simple model, the thin film is calculated to be only a few nanometers thick. At the beginning of the third region, only a thin film is left on the surface. Additional rolling leads to a rapid rise in friction and the transfer film thickness continues to decrease. The evidence supports the removal of PTFE out of the contact zone, and a high friction coefficient (mu = 0.6) is reached at the end of the test indicating an un-lubricated metal-metal contact. No major tribochemical reaction of PTFE is observed during this study. (c) 2006 Elsevier B.V. All rights reserved.},
	keywords = {(XPS), COMPOSITES, CONTACT, friction, friction modifier, INTERFACE, LUBRICATION, MODIFIER, polytetrafluoroethylene (PTFE), SURFACE, third body, TOP, WEAR, WHEEL-RAIL ADHESION, wheel/rail contact, X-ray photoelectron spectroscopy},
	isbn = {0043-1648},
	url = {<Go to ISI>://000242632600012},
	author = {Lu, X. and Wong, K. C. and Wong, P. C. and Mitchell, K. A. R. and Cotter, J. and Eadie, D. T.}
}
@article {1568,
	title = {Tracer diffusion in hard sphere fluids from molecular to hydrodynamic regimes},
	journal = {Journal of Chemical Physics},
	volume = {125},
	number = {20},
	year = {2006},
	note = {ISI Document Delivery No.: 110UZTimes Cited: 6Cited Reference Count: 43Sokolovskii, R. O. Thachuk, M. Patey, G. N.},
	month = {Nov},
	pages = {10},
	type = {Article},
	abstract = {Molecular dynamics is employed to investigate tracer diffusion in hard sphere fluids. Reduced densities (rho(*)=rho sigma(3), sigma is the diameter of bath fluid particles) ranging from 0.02 to 0.52 and tracers ranging in diameter from 0.125 sigma to 16 sigma are considered. Finite-size effects are found to pose a significant problem and can lead to seriously underestimated tracer diffusion constants even in systems that are very large by simulation standards. It is shown that this can be overcome by applying a simple extrapolation formula that is linear in the reciprocal cell length L-1, allowing us to obtain infinite-volume estimates of the diffusion constant for all tracer sizes. For higher densities, the range of tracer diameters considered spans diffusion behavior from molecular to hydrodynamic regimes. In the hydrodynamic limit our extrapolated results are clearly consistent with the theoretically expected slip boundary conditions, whereas the underestimated values obtained without extrapolation could easily be interpreted as approaching the stick limit. It is shown that simply adding the Enskog and hydrodynamic contributions gives a reasonable qualitative description of the diffusion behavior but tends to overestimate the diffusion constant. We propose another expression that fits the simulation results for all densities and tracer diameters. (c) 2006 American Institute of Physics.},
	keywords = {BOUNDARY-CONDITIONS, BROWNIAN PARTICLE, COEFFICIENT, DYNAMICS SIMULATION, friction, KINETIC-THEORY, RIGID PARTICLES, SINGLE-PARTICLE MOTION, SIZE DEPENDENCE, TRANSPORT-COEFFICIENTS, VELOCITY-AUTOCORRELATION FUNCTION},
	isbn = {0021-9606},
	url = {<Go to ISI>://000242408100031},
	author = {Sokolovskii, R. O. and Thachuk, M. and Patey, G. N.}
}
@article {2750,
	title = {DIELECTRIC-RELAXATION OF ELECTROLYTE-SOLUTIONS - IS THERE REALLY A KINETIC DIELECTRIC DECREMENT},
	journal = {Journal of Chemical Physics},
	volume = {98},
	number = {6},
	year = {1993},
	note = {ISI Document Delivery No.: KU222Times Cited: 31Cited Reference Count: 34},
	month = {Mar},
	pages = {4959-4966},
	type = {Article},
	abstract = {The dielectric behavior of model electrolyte solutions is studied by molecular dynamics simulations. For the systems considered, it is found that the zero-frequency dielectric constant depends only on equilibrium properties and that there is no measurable {\textquoteright}{\textquoteright}kinetic dielectric decrement.{\textquoteright}{\textquoteright} A theoretical explanation of the simulation results is presented. It is argued that no kinetic dielectric decrement exists for spherical ions in solvents of arbitrary molecular symmetry.},
	keywords = {AQUEOUS-ELECTROLYTES, COMPUTER-SIMULATION, CONSTANT, DISPERSION, DYNAMICS, ELECTROSTATIC SYSTEMS, friction, MOLECULAR THEORY, PERIODIC BOUNDARY-CONDITIONS, polarization},
	isbn = {0021-9606},
	url = {<Go to ISI>://A1993KU22200067},
	author = {Chandra, A. and Wei, D. Q. and Patey, G. N.}
}
@article {7146,
	title = {DIELECTRIC-RELAXATION OF ELECTROLYTE-SOLUTIONS},
	journal = {Journal of Chemical Physics},
	volume = {94},
	number = {10},
	year = {1991},
	note = {ISI Document Delivery No.: FL001Times Cited: 29Cited Reference Count: 49},
	month = {May},
	pages = {6795-6806},
	type = {Article},
	abstract = {The dielectric relaxation theory of electrolyte solutions is formulated in terms of solvent-solvent, ion-ion, and ion-solvent van Hove time correlation functions. General wave vector frequency-dependent expressions are given for the longitudinal components of the relevant (i.e., polarization-polarization, current-current, current-polarization, polarization-current) time correlation functions and of the susceptibility, dielectric, and conductivity tensors. The Kerr theory relating the distinct and self parts of the van Hove functions is extended to mixtures of molecular fluids and solved explicitly in the k {\textendash}> 0 limit for solutions of spherical ions (assuming that the self part of the van Hove functions is given by Fick{\textquoteright}s law) immersed in polar solvents. At this level of theory, the van Hove functions, the time correlation functions and the susceptibilities are all found to depend upon coupled ion-solvent motion. However, the dynamical coupling terms are shown to cancel exactly in the final expressions for the conductivity and dielectric constant yielding relatively simple results. Specifically, the conductivity obtained is independent of frequency and is related to the self diffusion constants of the ions by the Nernst-Einstein expression. If a spherical diffusor model is chosen for the solvent, then the frequency-dependent dielectric constant is given by a Debye-type formula with a concentration dependent relationship connecting the Debye and self reorientational relaxation times of the solvent. These results are discussed in the context of previous theories and experimental observations. It is shown that, although obviously oversimplified, the present theory does qualitatively predict the correct concentration dependence of the observed relaxation times for a number of salt solutions.},
	keywords = {DIPOLAR LIQUIDS, DISPERSION, FLUIDS, friction, INVARIANT EXPANSION, LIQUIDS, MEAN SPHERICAL MODEL, MOLECULAR THEORY, ORNSTEIN-ZERNIKE EQUATION, POLAR, TRANSLATIONAL DIFFUSION},
	isbn = {0021-9606},
	url = {<Go to ISI>://A1991FL00100048},
	author = {Wei, D. Q. and Patey, G. N.}
}
