Abstract: Enhanced micromachining rates are observed when lapping discs with standard SiO.sub.x lapping coatings are doped with trivalent or pentavalent additives, such as boron or phosphorous. Doping can be accomplished by subjecting the SiO.sub.x material to a "post glow", i.e., an argon plasma in the presence of a source of the dopant.

Abstract: There is disclosed a process for the separation of ethylene or propylene from a purified, multi-component gas stream produced from the thermal cracking of hydrocarbons and containing ethylene or propylene and other low molecular weight components comprising the steps of: introducing said multi-component gas stream into an aqueous silver salt solution stream to effect the absorption and/or complexing of said contained ethylene or propylene and reaction of trace acetylenes with the silver metal ions of such solution; venting of the silver salt solution stream at reduced pressure to remove the dissolved other low molecular weight components; treating the resulting silver salt solution stream to separate the absorbed and/or complexed ethylene or propylene from the silver salt stream; further treating the resultant silver salt solution stream to release the contained trace acetylenes therefrom and provide an aqueous silver salt stream; and recycling said aqueous silver salt stream to said introducing step.