The objective was to evaluate the impact of additional lubricant on condom breakage and slippage. Two hundred and sixty-eight couples used 6 new and 6 aged condoms during vaginal intercourse and were instructed to use 2 of each type with either water-based lubricant, oil-based lubricant or no additional lubricant. The use of either oil-based or water-based lubricant increased slippage rates of ...

In disk drive technology, lubricant thickness and roughness are important, but often overlooked, contributors to slider–disk spacing. In this paper, we use X-ray reflectivity to measure the thickness and lubricant–air roughness of a perfluoropolyether lubricant (Fomblin Zdol) on silicon wafers and carbon overcoats. For Zdol on smooth silicon, the roughness increases with increasing lubricant th...

Using shear dynamics simulations we investigated the structure and dynamics of hexadecane (n-C 16 H 34) lubricant lms connned between two solid surfaces (Fe 2 O 3) covered with a self-assembled monolayer of wear inhibitors dithiophosphate molecules DTP = S 2 P(OR) 2 with R = iPr, iBu, and Ph]. We found signiicant density oscillations in the lubricant lms, especially near the top and bottom boun...

Understanding the physical behavior of polymer-based lubricants on the nanoscale is of critical importance to a myriad of engineering applications and devices. We have used molecular dynamics simulations to quantitatively evaluate the physical mechanisms underlying perfluoropolyether lubricant spreading on a solid substrate. We quantify the effect of molecular mass, molecule length, and lubrica...

This paper explains the effect of various lubricant and engine temperatures on the intake mass air flow, engine noise and lubricant pressure behaviour of a motor-driven spark ignition engine. The lubricant pressure, engine noise and mass air flow changes were recorded under a steady state operating condition with an increased engine speed in which both the volume and temperature of the lubrican...

Vapor phase lubrication is considered one of the most likely means of lubricating MEMS devices with replenishable solid films. Since gas phase diffusion is the primary means of vapor lubricant transport into the long, narrow channels of MEMS devices, it is necessary to determine that this is sufficient to replenish lubricant films worn at high rates. The diffusion of vapor phase lubricant into ...

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...

OBJECTIVE Over-the-counter vaginal lubricants have been shown to negatively affect in vitro sperm motility. The objective of this study was to estimate the effect of vaginal lubricant use during procreative intercourse on natural fertility. METHODS Women aged 30-44 years with no history of infertility who had been trying to conceive for less than 3 months completed a baseline questionnaire on...

Ultra-thin lubricant films are essential in the design of nanoscale systems and devices as surface effects become increasingly important on the nanoscale. We have used molecular dynamics simulations to quantify terraced spreading of perfluoropolyether lubricant on a flat substrate as a function of polymer chain length, lubricant thickness, and functional end groups of the lubricant and the subs...