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The paper describes an experimental technique combining optical interferometry and ultrasonic attenuation to measure the bulk modulus (compressibility) and film thickness profiles of oil and grease films entrapped between a stationary steel ball and a sapphire plate. Results are presented for lithium- and urea-based greases, and their base oils alone, at contact pressures up to and around 3 GPa, and are compared with some models and results from other studies, extrapolated to the higher pressures achieved here. Results show that the bulk modulus of a particular grease and its base oil are found to be similar, at a given pressure, and largely dependent on the base-oil properties, which is demonstrated to be what is expected with the concentration levels of fillers and solid lubricants present. However, the film shapes measured for the grease and its base oil can be quite different. This is seemingly due to the manner in which the lubricant samples 'solidify', due to the high pressures, and also to the way in which the edges of the squeeze-film entrapped fluid are sealed. This latter sealing effect seems to be assisted by secondary phases, particularly with greases where fillers and solid lubricants are present, creating a very effective sealed contact where the entrapped lubricant samples could be observed to remain stable for several hours. [DOI: 10.1115/1.2125887]

An approximately 15 [mu]m thick polymer film doped (approximately 5 mM) with a laser dye, when coated on large pseudotabular Ag islands and pumped by a nanosecond laser, generates a single sharp stimulated emission with a bandwidth down to 2.5 nm. This low-threshold (approximately 1 ml/[cm.sup.2]) lasing action is attributed to the surface-enhanced fluorescence of the dyes very near the Ag islands.

Excitation diffusion is studied in 5-25-nm-thick films of zinc tetra-(p-octylphenyl)-porphyrin (ZnTOPP) spin-coated onto quartz slides by doping with quenchers using steady-state and time-resolved fluorescence spectroscopy. The neighboring stacks aggregate in a herringbone structure, forming ordered domains that were randomly oriented in the substrate plane, and an energy-transfer rate constant of (7 plusmn 2) x 10(super 10)s(super minus1).

A technique is formulated to determine both thickness and refractive indices of free-standing films with biaxial symmetry from polarized transmission spectra. The films must be transparent and are found to show little dispersion in refractive indices in the wavelength range where the transmission spectra are collected.

A one-dimensional (1D) bulk absorption model to simulate the accelerating process of laser-driven flyer plate, in which the laser energy deposition and acceleration of flyer plates are included, is presented. The calculations show that an aluminum foil of original thickness of 10 Mu m may be accelerated to a velocity of about 2 km/s, the calculated average ionized charge number of plasma Z is >3 peak temperature and plasma pressure is in the order of 2.1X10(Super 5) K and 1.5 X 10(Super 3) GPa, respectively, and the maximum Rosseland opacity is about 1.9 X 10(Super 5) cm-1.

Kerr microscopy is used for examining the domain structures in patterned magnetostrictive Ni(sub x)Fe(sub 1-x) films. An anisotropic structured patterned is observed for positive magnetostriction films.

Laser pulse was taken as directed input of finite element analysis rather than the measurement of the free surface velocity. Numerical simulation of measurement of the film- matrix interface strength by laser spallation was investigated.

Thick films of lithium niobate are epitaxially grown on sapphire substrates by multistep radio frequency magnetron sputtering. Results indicate that the angular width of the excited optical guided modes varies with the film thickness.

It is shown that the refractive index and thickness of nanocrystalline diamond (NCD) films can be measured accurately by the prism coupling technique. The index of the NCD films was found homogeneous within the films with negligible changes observed at the film-substrate interface and the overall results suggest the reliability and consistency of the continuous controlled bias current density process to grow NCD in a MPCVD system.

The results of investigations of lithium niobate (LiNbO3) films grown on (0001) sapphire substrate by radio-frequency magnetron sputtering are presented. The film properties between each growth step and between the substrate to layer interface, directly from the measured optical data are qualified.