A precision spin stand was used to study the effects of pitch static angle and roll static angle on lubricant transfer between a disk and a slider in a hard disk drive. The lubricant distribution on the slider was determined by timeof-flight secondary ion mass spectrometry, while the lubricant distribution on the disks was obtained using optical surface analysis. Lubricant transfer from the dis...

Perfluoropolyethers ~PFPE! are used extensively to lubricate hard disks for high density information storage. Some PFPE lubricants have been shown to be vulnerable to dissociative electron attachment as well as electron bombardment. Triboelectric charges generated during sliding contact may generate quasi-free electrons capable of degrading the lubricant. We describe measurements of triboelectr...

Clustering is an unsupervised learning technique that seeks “natural” groupings in data. One form of data that has not been widely studied in the context of clustering is binary data. A rich statistical framework for clustering binary data is the Bernoulli mixture model for which there exists both Bayesian and non-Bayesian approaches. This paper reviews the development and application of Bernou...

A recently developed analytical version of the discrete-ordinates method is used to establish a concise and particularly accurate solution to the problem of Couette #ow of a binary gas mixture in a plane channel. The model kinetic equations used to describe the #ow are based on the BGK theory of the linearized Boltzmann equation, and, in addition to the complete distribution functions for the t...

When the re:fiigerant R l34a is mixed with an ester oil and usea m compressor bearing lubrication, no EP action is experienced. The refrigerant contains no chlorine and the lubricant additives can not be chemically active like normal EP additives, not to deposit in and destroy the heat excha..>Jgers. The iubricant film thickness thus needs to be considerably larger for an Rl34a compressor beari...

The a-master functions of the mode coupling theory for a binary soft-sphere mixture are presented. They are directly determined by the static structure factors S,. The asymmetric stretching of the susceptibility spectra, which is mainly caused by the common von Schweidler high frequency asymptote, is well described by Kohlrausch fits. The stretching parameters and a-relaxation times for various...

We experimentally study one-dimensional, lattice-modulated Bose gases in the presence of an uncorrelated disorder potential formed by localized impurity atoms, and compare to the case of correlated quasidisorder formed by an incommensurate lattice. While the effects of the two disorder realizations are comparable deeply in the strongly interacting regime, both showing signatures of Bose-glass f...