Abstract: Low silica ceramic fiber compositions comprising from 46-49% alumina, 23-25% silica and 27-29% zirconia.

Abstract: A coking process in which tar impregnated refractory products are heated in a muffle within a furnace to a temperature sufficient to cause emission or release of the volatile constituents in the tars and pitches used for impregnation, whether by decomposition or distillation, for a time which is sufficient to remove substantially all of such constituents from the products, characterized by heating the refractory products in a muffle within the furnace while maintaining a positive pressure within the muffle during the emission of the volatile constituents, and thereafter cooling the refractories in a substantially nonoxidizing atmosphere. After the temperature of the refractory products is low enough to avoid any thermal shocking of the brick the brick are removed from the furnace and the muffle.

Abstract: A new group of bulk polycrystalline materials which are capable of exhibiting, selectively, either memory switching or threshold switching. The body of the material, which can be molded into a suitable ceramic resistor configuration with ohmic electrodes and a sintered body composition, comprises as a majority proportion zinc oxide with the balance being another polycrystalline inorganic oxide such as bismuth oxide, cobalt oxide, chromium oxide, antimony oxide, praseodymium oxide, lanthanum oxide, holmium oxide and manganese oxide, or mixtures thereof.

Abstract: An improved process for preparing active oxide powders in which cation hydroxide gels, prepared in the conventional manner are chemically dried by alternately washing the gels with a liquid organic compound having polar characteristics and a liquid organic compound having nonpolar characteristics until the mechanical water is removed from the gel. The water-free cation hydroxide is then contacted with a final liquid organic wash to remove the previous organic wash and speed drying. The dried hydroxide treated in the conventional manner will form a highly sinterable active oxide powder.