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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Relative rate experiements were used to measure rate constants and temperature denpendencies of the reactions of OH with propane, n-butane, n-pentane, n-hexane, cyclopropane, cyclobutane, cyclopentane, and dimethyl ether.
High temperature tests to determine fatigue life of 120mm bore ball bearings with fluorocarbon, polyphenyl ether, and synthetic base paraffin base lubricants
Steroid trimethylsilyl ethers, analyzing peaks in mass spectra using deuterium labeling
Polysiloxane-s-triazinyl ether preparation, noting structural and physical properties of compounds
Lubrication performance and thermal shear degradation of polyphenyl ethers and refined mineral oils in high temperature vane pump loop
Lewis acidity of alanes, discussing interactions of trimethylalane with amines, ethers and phosphines
Large scale synthesis of amorphous poly/vinyl ethers/ for viscoelastic state study
Determining effect of humidity and wettability additive on boundary lubrication of steel in air and nitrogen with polyphenyl ether
Polyvinyl alkyl ethers multiple transitions at low temperatures, using linear variable differential transformer
Method for producing alternating ether-siloxane copolymers with stable properties when exposed to elevated temperatures and UV radiation
Chemical synthesis of hydroxy terminated perfluoro ethers as intermediates for highly fluorinated polyurethane resins
Test of rolling element fatigue life with fluorinated ether lubricant at cryogenic temperature using five ball fatigue tester
The preparation of poly(polyfluoroalkylene-glycol) mono (hydroxy polyfluoroalkylene) ethers from fluoroalkylene oxides is described.
The characteristics of organosilicon compounds for lubrication under extreme conditions are discussed. The substances considered are thiophenyl ether disiloxanes and trisiloxanes. These substances have low pour points and a high degree of radiation resistance. Substitution of sulfur for the phenoxy group oxygen of either siloxane compounds has been found to result in a marked improvement in lubricity. The chemical formulas of the organic compounds are presented.
The types of wear particles generated by a five-ring polyphenyl ether in boundary lubrication experiments in various atmospheres were determined by ferrographic analysis. The types of wear particles observed included cylindrical or rocklike organometallic debris, adhesive and cutting wear particles, and some spherical debris. Interpretations as to the mechanism of generation of the various types of particles are presented.
A minimum films thickness correlation applicable to heavily loaded elastohydrodynamic (EHD) contacts was formulated from experimental data obtained by an X-ray transmission technique. The correlation, based on data generated with fluorocarbon, type II ester, and polyphenyl ether lubricants, extends a previous analysis developed from data for a synthetic paraffinic oil. The resulting correlation represents the data of the four lubricants reasonably well over a large range of operating conditions. Contained within the derived relation is a factor to account for the high-load dependence displayed by the measurements beyond that which is provided for by the theory. Thermal corrections applied to a commonly used film thickness formula showed little improvement to the general disagreement that exists between theory and test. Choice of contact geometry and material are judged to have a relatively mild influence on the form of the semiempirical model.
Rolling-element fatigue tests were conducted with 12.7-mm-(1/2-in.-) diameter AISI 52100 steel balls in the NASA five-ball fatigue tester, with a maximum hertz stress of 5500 mN/m2 (800 000 psi), a shaft speed of 4750 rpm, lubricant temperature of 200 K (360 R), a contact angle of 20 deg, using four fluorinated ether lubricants of varying viscosities. No statistically significant differences in rolling-element fatigue life occurred using the four viscosity levels. Elastohydrodynamic calculations indicate that values of the lubricant film parameter were approximately 2 or greater.
The types of wear particles generated by a five-ring polyphenyl ether in boundary lubrication experiments in various atmospheres were determined by ferrographic analysis. The types of wear particles observed included: cylindrical or rock-like organo-metallic debris, adhesive and cutting wear particles, and some spherical debris. Interpretations as to the mechanism of generation of the various types of particles are presented.