The lubricant is a critical component of an automotive AJC system. Besides providing good lubricity, it must exhibit sufficient solubility in the refrigerant to ensure lubricant return to the compressor. Stability in the presence of the refrigerant, metals, and common contaminants such as air, water, and mineral oil is critical. The lubricant must also be compatible with the hoses and other ela...

The hazardous organic residual wastes produced by the sodium hydrosulfite industry are demonstrated to be convertible into a novel solid lubricant. Identification and isolation of the organic residues are achieved by Fourier transform infrared (FTIR) spectroscopy, gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR). FTIR and GC-MS provide important information abo...

This paper presents the development of hall effect sensor for measuring the contamination of lubricant in industry. This technique is based on the principle of the magnetic field and Hall Effect. The magnetic field is made up of a permanent magnet which is measured by a Hall Effect sensor. The measured magnetic field can be estimated the level of contaminants in the oil by the ferrous particles...

The melting of an ultrathin lubricant film is studied at friction between atomically flat surfaces. We take into account fluctuations of lubricant temperature, which are defined by the Ornstein-Uhlenbeck process. Phase diagrams and portraits are calculated for secondand first-order transitions (the melting of an amorphous and that of a crystalline lubricants, respectively). It is shown that, in...

Melting of an ultrathin lubricant film confined between two atomically flat surfaces is studied using the rheological model for viscoelastic matter approximation. Phase diagram with domains, corresponding to sliding, dry, and two types of stick-slip friction regimes has been built taking into account additive noises of stress, strain, and temperature of the lubricant. The stress time series hav...

OBJECTIVE To compare the level of pain experienced by patients during transrectal ultrasound-guided prostatic biopsy using intrarectal 2% lidocaine gel versus plain lubricant gel. DESIGN Prospective double-blind randomised controlled trial. SETTING Regional hospital, Hong Kong. PATIENTS From March 2002 to December 2003, patients who underwent ultrasound-guided prostate biopsy at a Geriatr...

This paper presents the experimental results of normal lubricant, additives added lubricants and waste vegetable oil (WVO) contaminated bio-lubricants to evaluate the tribological properties such that friction and wear characteristics. The test was conducted using a four-ball tribotester with standard test method IP239. The balls used in four-ball tribotester were based on carbon-chromium steel...

In this work we study finite-size effects of nanoscale lubricant 2D droplets (or islands) by molecular dynamics. A small lubricant droplet is confined between two 2D crystalline layers; the bottom layer is static, while the top one slides rigidly. Simulations show that small nearly-lattice-matched islands can snap to commensuration entirely, changing their initial particleparticle distance ap t...

Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid ass...

wind gearbOx technOLOgy is developing at a fast pace, not least due to operators demanding ever more power and efficiency. Experience has shown that the lubricant used is a crucial factor in meeting the wish for ever-increasing performance. Besides strictly technical requirements, aspects of economy and ecology are receiving more and more attention in lubricant selection. The technical requirem...