Silicon-bearing minerals

Emission spectroscopy analyses of the anthracites (Table IX) show that 90% of the ash of Pennsylvania anthracites is composed of silicon, aluminum, and iron-bearing minerals. 

Silicon (Si ") Bearing Minerals Table 412 Crare-earth elements in titanite sample (ppm)... 

Suspensions of solid lubricants are used as a colloidal or partially colloidal dispersion, in mineral oils, polyglycols or silicone oils as carrier liquids. These suspensions are used to impregnate sintered bearings or added to running-in oils for bearings. 

Silicone oils are good hydrodynamic lubricants but have generally poor frictional lubricating properties (352—354). The latter can be improved by incorporating chlorophenyl groups into the polymer side chains (355). For steel on steel, the coefficient of friction is about 0.3—0.5. The load-bearing capacity of PDMS (Almen-Wieland machine) is only 50—150 kg, compared with 1000 kg for polychlorophenylmethylsiloxane and up to 2000 kg for mineral oil. 

Miner, J. R., Grace, W. A., and Valori, R. (1980). Demonsnation of High-speed gas Turbine bearings using silicon nitride rolling elements, ASLE Preprint, 80-AM-3C-3. 

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