Abstract: There has been discovered the increased E-Modulus and grinding performance of vitreous bonded sol-gel abrasive grit abrasive articles, particularly abrasive grinding wheels, by the incorporation therein of inorganic, non-metallic bubbles. In a practice of the invention the abrasive article comprises a) an abrasive phase having sintered sol-gel alumina abrasive grits and second abrasive grits that are not of the sintered sol-gel type, b) a vitreous bond and c) essentially hollow, essentially spherical alumina particles having a softening temperature at least 50.degree. F. greater than the firing temperature of the vitreous bond.

Abstract: An improved process for making an alcohol by hydration of an olefin in the presence of a cation exchange resin in the acid form as catalyst and in the presence of a solvent for the reactants and product alcohol, wherein the solvent and reactants are introduced to the reactor as a single homogeneous phase to a first-stage reactor. Part of the olefin is added to a second-stage reactor. The effluent from the second stage is passed to a third-stage reactor and the unreacted olefin and solvent from the third-stage effluent are recycled to the first-stage reactor after removal of substantially all of the product alcohol. The process provides improved conversions and yields and enables the use of smaller amounts of solvent.