Abstract: Uniform sialon powders having a sharp particle size distribution are obtained by mixing (i) amorphous silicon nitride powders, (ii) an oxygen-containing compound of silicon or/and aluminum, and (iii) aluminum metal, aluminum nitride and/or silicon, and then heating the resultant mixture at 1300.degree. to 1800.degree. C. in an atmosphere containing nitrogen.

Abstract: An aluminum nitride ceramic body with a thermal conductivity of at least 0.5 W/cm.multidot.K at 25.degree. C. is produced by shaping a particulate mixture of aluminum nitride powder and an additive selected from the group consisting of YF.sub.3, ScF.sub.3, LF.sub.3 where L is La, Ce, Pr, Nd, Sm, Gd, Dy, Ho and Er and a mixture thereof into a compact and liquid phase sintering the compact.

Abstract: A building material plate formed by compression in the hydration-water moist state and having quality features resembling asbestos-reinforced cement and made of an asbestos-free material mixture having up to 30 vol. % of cellulose fiber proportions in the high-packed state of a diameter spectrum D.sub.C, singly bound into a hydration binder particle mixture still present in the moist forming state of a grain size-main distribution spectrum D.sub.o within the ratio range0.9.ltoreq.D.sub.C /D.sub.o .ltoreq.1.1,which in case of a participation of cement in the binder contains special additives showing a pozzuolana reaction for securing constancy in longterm quality.

Abstract: The invention relates to an admixture to be used in preparing a fresh concrete with enhanced flowability and air-entraining property.

Abstract: A method of producing self-supporting ceramic structures comprising (i) a polycrystalline oxidation reaction product formed upon oxidation of a body of molten parent metal with an oxidant, and (ii) interconnected porosity at least partially accessible from one or more surfaces of said ceramic body. A second polycrystalline ceramic material is incorporated into the porosity of said ceramic body to modify or contribute to its properties.

Abstract: A ceramic material which comprises a composite of zirconia and O'-sialon or silicon oxynitride.The ceramic material may comprise a dispersion of zirconia in an O'-sialon matrix and such a dispersion is obtained when the amount of zirconia is from 5 to 30 volume percent, preferably 15 to 25 volume percent, based on the total volume of the composition.

Abstract: The invention is generally accomplished by forming a three-dimensionally shaped, externally worn feminine protection device which has been mechanically shaped by folding, molding or other forming techniques in such a way that it has a raised portion located within the back one-half to two-thirds of the device that functions to cause the pad to readily fit to and generally align itself within the inverted V-shaped regions of the woman's lower abdominal region, vulva, perineum and the anterior portion between the buttocks. The forward portion of the device of the invention generally is flattened in use to cover externally the area of the pubic mons and the area exterior of the clitoris. The back portion of the device is formed in a peak like shape which readily adjusts to and molds to the inverted V-shape of the rear portion of the labia, the perineum and the forward portion of the area between the buttocks.

Abstract: The invention is a molded body of polycrystalline aluminum nitride having a density of at least 99.8% TD and comprising:at least 99% by weight AlNup to 0.35% by weight residual oxygenup to 0.35% by weight residual carbon andup to 0.03% by weight metallic impurities (Fe, Si, Ca, Mg).In the molded body, the aluminum nitride is present in the form of a single phase, homogeneous, isotropic microstructure having a maximum grain size of 5 .mu.m. The residual oxygen and the residual carbon are present in the form of a solid solution in the aluminum nitride lattice and caromografically not detectable as separate phase(s) up to a magnification of 2400 times. The molded bodies have a bending strength measured according to the 4-point method, at room temperature and up to about 1400.degree. C., of at least 500 N/mm.sup.2, a predominantly transcrystalline rupture modulus and a thermal conductivity at 300 K of at least 150 W/mK.

Abstract: Refractory fibers comprising a homogeneous mixture of 60 to 95 weight percent amorphous alumina and 40 to 5 weight percent amorphous phosphorus pentoxide. The fibers optionally can contain chloride, and up to 20 weight percent carbon derived from the alumina precursor material. Other organic residues can be present. The fibers are useful in the manufacture of fireproof consumer fabrics as well as reinforcement or polymeric composites.

Abstract: A high-toughness ceramic tool material consisting essentially of 50-95% by volume of a main sialon base phase wherein at least 10% by volume of the sialon base phase consists of alpha-sialon, and 5-50% by volume of a SiC whisker phase. This ceramic material is produced by sintering a composition comprising:50-95% by volume of a sialon forming component such that at least 10% by volume, calculated on the entire sialon, of alpha-sialon is formed, and5-50% volume of SiC whiskers;said sialon forming component consisting essentially of 50-95% by weight of Si.sub.3 N.sub.4 and 50-50% by weight of constituents of sialon-consistituting elements other than Si.sub.3 N.sub.4,said constituents consisting of a mixture of AlN and Al.sub.2 O.sub.3, and at least one oxide selected from the group consisting of oxides of yttrium and rare earth elements, said mixture of AlN and Al.sub.2 O.sub.

Abstract: The particulate solid is maintained in a bed in contact with a liquid within a high pressure vessel. The particulate solid is supported in the vessel in a cone-like configuration. A discharge tube is provided communicating with the particulate solid running from the bottom of the cone externally of said vessel and pressure on the supported particulate is produced to discharge said particulate out of said vessel via the discharge tube.

Abstract: An improved process for producing a translucent polycrystalline alumina body comprising rapid-sintering a prefired compacted green body of alumina of predetermined shape is disclosed. The green body of alumina includes alumina doped with one or more sintering aids. Rapid sintering in accordance with the method of the present invention comprises the steps of raising the temperature of the prefired compacted green body of predetermined shape up to maximum sintering temperature at a heating rate greater than or equal to about 0.1.degree. C./second and less than the rate at which the green body experiences thermal shock; and heating the green body at the maximum sintering temperature for a period of time sufficient to produce a translucent polycrystalline alumina body. The rapid sintering is carried out under a flowing gas mixture of nitrogen and at least about 2.5 volume percent hydrogen.

Abstract: An electrically conductive hot press sintered ceramic product comprising boron nitride, titanium diboride and aluminum nitride and having a flexural strength of at least 900 kg/cm.sup.2, a specific resistance of from 300 to less than 2,500 .mu..OMEGA.cm and less anisotropy.

Abstract: A dielectric ceramic composition for high frequencies consisting essentially of a basic composition expressed by the general formula:xMgO--yAl.sub.2 O.sub.3 --zSiO.sub.2wherein x, y and z are mole percentage of the respective components, x+y+z=100, 65.ltoreq.x.ltoreq.77, 1.ltoreq.y.ltoreq.15, and 8.ltoreq.z.ltoreq.34 and an exclusive additive of 0.1 to 10.0 weight % of Li.sub.2 O. The basic composition has a set of x, y and z falling within an area defined by a polygon ABCD encompassed by the points A, B, C and D in FIG.

Abstract: Disclosed is a spray concrete which, even at a water-cement ratio of 0.45 to 0.55, is still easy to work, can be sprayed well, and sets and hardens rapidly. It contains, in addition to the conventional additives, additions of naphthalinesulfonicacid-formaldehyde condensation products and highly concentrated alkaline aqueous solutions of potassium aluminate, potassium carbonate and caustic potash. The concrete according to the invention displays an especially rapid solidification when it contains up to 3% by weight alkali silicates or an adequate amount in highly dispersed silicic acid (SiO.sub.2). The additives are incorporated into the concrete preferably directly at the worksite prior to spraying.

Abstract: A type I dielectric composition based on neodymium titanate is formed of a mixture comprising 58% to 78% by weight of neodymium titanate (Nd.sub.2 O.sub.3 -3TiO.sub.2), 10 to 21% by weight of lead titanate (PbTiO.sub.3), 5% to 14% by weight of barium titanate (BaTiO.sub.3), 4% to 15% by weight of barium zirconate (BaZrO.sub.3) and 0.2% to 1.2% by weight of yttrium oxide (Y.sub.2 O.sub.3).

Abstract: A polycrystalline body having a composition comprised of Y.sub.2-x Sr.sub.x O.sub.3-x/2 wherein x ranges from about 0.0015 to about 0.012.

Abstract: A crystallized glass-ceramic molded product having a glass matrix and crystallized calcium fluoride and fluormica dispersed therein. The molded product is prepared by mixing and melting together the necessary constituents for forming the glass, calcium fluoride and fluormica and rapidly cooling the melt to produce a frit. Particles of the frit or of two or more frits are then subjected to sintering and crystallizing heat treatments.

Abstract: An aluminum nitride-based sintered body having a high thermal conductivity and a total oxygen content of 0.01 to 20% by weight which is prepared by mixing a main component of aluminum nitride powder containing 0.001 to 7% by weight of oxygen with 0.01 to 15% by weight of at least one of the group consisting of a powder of a rare earth element and/or a powder of a material containing the rare earth element (said 0.01 to 15% by weight being counted on the basis of the content of the rare earth element), and sintering said powder mixture.

Abstract: A process for producing an aluminum nitride ceramic body having a composition defined and encompassed by polygon ABCDEFGH excluding line DE of FIG. 2, a porosity of less than about 10% by volume, and a thermal conductivity greater than 0.70 W/cm.multidot.K at 25.degree. C. which comprises forming a mixture comprised of aluminum nitride powder containing oxygen, an Ln oxide selected from the group consisting essentially of erbium oxide, holmium oxide, a mixture and solid solution thereof, and free carbon, shaping said mixture into a compact, said mixture and compact having a composition wherein the equivalent % of Ln and aluminum ranges from point A up to point E of FIG. 2, said mixture and said compact having an equivalent % composition of Ln, Al, O and N outside the composition defined and encompassed by polygon ABCDEFGH of FIG.