Abstract: A new polymerization catalyst system comprising an aluminum compound and a transition metal compound on an alumina-based aerogel support, a process for preparing the polymerization catalyst system and use of the catalyst system for polymerization and copolymerization of alpha-olefins are disclosed. A heat-activated alumina-based aerogel useful as a catalyst support and having a morphology by transmission electron microcopy comprising extremely thin folded film-like ribbons or plates and having a high BET surface area, high pore volume, and low bulk density is also disclosed.

Abstract: Finely divided, hydrogen-activated catalyst compositions comprising iron, silicon and carbon or iron and silicon that selectively convert gaseous mixtures of CO and H.sub.2, at a temperature of about 150.degree.-450.degree. C. and at pressures of about 10-2000 kPa, into reaction mixture containing at least about 75% C.sub.2 -C.sub.6 alkenes and no more than about 25% of CH.sub.4 and undesirable CO.sub.2 by-products are disclosed. A wide range of iron/silicon-based catalyst compositions are conveniently prepared by laser pyrolysis and hydrogen-pretreatment and readily reactivated with hydrogen at elevated temperatures.

Abstract: Rapidly solidified chromium and cobalt free superalloy powders are described. The compositions of the alloys are as follows:Ni.sub.Bal Al.sub.a Ti.sub.b Nb.sub.c Hf.sub.d Mo.sub.e Zr.sub.f B.sub.gwhere the subscripts of the elemental additions are atomic percents and have the following values;a=10-15b=3-10c=0-4d=0-4e=0-4f=0-1g=2-5These alloys maintain their strength at temperatures in excess of 800.degree. C. and show excellent oxidation resistance.