Abstract: A dielectric ceramic for use in an electrostatic chuck, formed by firing in a reducing atmosphere a ceramic material mainly comprised of alumina, wherein said ceramic material comprises an alkaline earth metal in an amount of from 1.0 to 6.0% by weight in terms of oxide and a transition metal in an amount of from 0.5 to 6.0% by weight in terms of oxide, while controlling the dew point of atmosphere gas to be not more than 45.degree. C.Also disclosed is a method of making a dielectric ceramic for use in an electrostatic chuck, comprising firing a ceramic material mainly comprised of alumina and containing from 1.0 to 6.0% by weight of an alkaline earth metal in terms of oxide and from 0.5 to 6.0% by weight of a transition metal in terms of oxide, in a reducing atmosphere while controlling the dew point of atmosphere gas.

Abstract: Aqueous compositions of emulsified oxyaluminum acylate solutions comprising solutions of oxyaluminum acylate in a largely water insoluble solvent, an alcohol or an organic acid, an emulsifier or mixture of emulsifiers, and water are provided. Articles comprising substrates rendered water-repellent with such emulsions are provided as well. A process for the preparation of such articles is also provided.

Abstract: A composition is disclosed which is useful for the water-repellent impregnation of porous mineral building materials. The composition is based on organosilicon compounds which contain alkoxy groups and comprises an emulsion which contains 2.5 to 25% by weight of an alkoxysilane of the formulaR.sup.1 -Si(OR.sup.2).sub.3whereinR.sup.1 is an alkyl group with 3 to 12 carbon atoms andR.sup.2 is a methyl or ethyl group, 2 to 20% by weight of an alkoxysiloxane of the formula ##STR1## wherein R.sup.3 is an alkyl group with 1 to 6 carbon atomsa is 0.8 to 1.2 andb is 0.2 to 1.2,0.01 to 5% by weight of an emulsifier, 0.01 to 0.1% by weight of fillers with an effective surface area of at least 40 m.sup.2 /g and 49.9 to 95.48% by weight of water. The composition has a long shelf life and, due to its high penetration, a high water-repellent effect on the surface, as well as deep within, all mineral building materials.

Abstract: A building element based on plaster which is manufactured by dry mixing sand and plaster, by dampening the mixture, by placing the damp mixture in a mold, and by compressing the mixture in the mold while the plaster hydrates in order to densify the crystal lattice of the plaster. The building element (10) includes self-alignment projections (14) on its top face (12) and a vertical groove (22) at one of its ends for the purpose of casting a liquid sealant, such as plaster.

Abstract: A method for fabricating a high-temperature ceramic superconductor having a Y-Ba-Cu-O or other copper-oxide composition of comparable properties so as to render the ceramic porous to define interlaced diffusion channels throughout the entire body of the ceramic. As a consequence, oxygen, an essential component thereof, will in the course of firing the ceramic, diffuse throughout the interior of the body and thereby interact and become integrated with the crystal structure of the ceramic to form a superconductor having superior properties. The resultant porous ceramic body may be used as a superconductive device, or it may be ground into particles and dispersed as a filler in a binder acting as a plastic agent that can be extruded, molded, or otherwise shaped to create a Meisner-effect shield, a cylindrical superconductive bearing or other superconductive structure.

Abstract: According to the invention a pozzolan is selected which exhibits a capacity for fixing lime during the Chapelle test at 90.degree. C. greater than 700 mg of CaO per gram of pozzolan, a capacity for fixing lime during the Chapelle test at 50.degree. C. greater than 200 mg of CaO per gram of pozzolan and a ratio of the quantity of CaO fixed during the 50.degree. C. Chapelle test to the specific surface area of the pozzolan which is greater than about 10 mg of CaO per square meter of pozzolan. The composite material obtained is used in construction to produce facade elements, for example, which have improved resistance to aging.

Abstract: A copolymer reaction product of a salt of a quaternary acrylate and a polyalkylene glycol acrylate. The copolymer is useful as an anti-static agent in anti-static varnish compositions for packaging gravure printing.