Abstract: A method of making a glass article such as an optical waveguide preform is disclosed. The method comprises drawing a rod in at least two steps. In the first step an elongated, consolidated preform having an aperture therethrough is drawn to a reduced diameter preform. The second step involves drawing the reduced diameter preform into a rod, preferably at a lower temperature than the first step. The method substantially reduces the formation of inclusions in the glass article during drawing.

Abstract: A method for heated mold changing at a forming station (24) is performed by apparatus (32) in a heated chamber (22) where heated glass sheets are cyclically formed. A switching station (318) is located adjacent the forming station (24). An unloading station (320) and a mold preheating station (322) are each located adjacent the switching station. An unloading cart (324) is initially movable from the loading station (320) to the switching station (318) and then to the forming station (24) to receive one or more heated molds from the forming station and is subsequently moved from the forming station back through the switching station to the unloading station to permit unloading of each heated mold. A loading cart supports a second mold or a pair of molds for heating within the mold preheating station (322) and is movable from the mold preheating station to the switching station (318) and then to the forming station for mold loading.

Abstract: In a method for producing a streak-free quartz glass sheet with a highly homogeneous degree of refraction, a quartz glass rod is lowered into a melting pot parallel to a longitudinal axis of the quartz glass rod. A cross-section of the melting pot is larger than a cross-section of the quartz glass rod and determines a contour of the quartz glass sheet. The quartz glass rod is heated in the melting pot to a flow temperature whereupon the quartz glass rod is lowered until the quartz glass rod melts and a height of the quartz glass flowing in the melting pot reaches a desired quartz glass sheet thickness. The melting pot and the quartz glass rod move relative to each other in a direction which is perpendicular to the longitudinal axis of the quartz glass rod during the melting process. Preferably, the movement involves a rotational and a transverse movement.

Abstract: A smoking deterring ashtray device for using as a smoking deterrent to get the user to stop smoking. The smoking deterring ashtray device includes a base member; and also includes a body assembly including a torso-shaped body member being securely disposed upon said base member and having a passageway extending therethrough with the torso-shaped body member further having an upper portion, a lower portion and a front; and further includes an ashtray assembly including a container being securely mounted upon the base member; and also includes a cigarette/cigar support assembly being securely disposed upon the container and being disposed upon the front and at the lower portion of the torso-shaped body member.

Abstract: A glass quenching apparatus for quenching a glass sheet heated to a predetermined temperature, includes a first nozzle group for jetting blower air onto opposite surfaces of the glass sheet, and a second nozzle group for jetting compressor air onto at least one of the opposite surfaces of the glass sheet. The first nozzle group is comprised of stationary nozzles, and the second nozzle group is comprised of movable nozzles which are capable of moving parallel to a plane of the glass sheet. The glass quenching apparatus of the foregoing construction is able to quench the glass sheet uniformly over the entire area thereof without undue wastage of quenching air.

Abstract: A film of fluorine-doped silicon glass (“FSG”) is exposed to a nitrogen-containing plasma to nitride a portion of the FSG film. In one embodiment, the FSG film is chemically-mechanically polished prior to nitriding. The nitriding process is believed to scavenge moisture and free fluorine from the FSG film. The plasma can heat the FSG film to about 400° C. for about one minute to incorporate about 0.4 atomic percent nitrogen to a depth of nearly a micron. Thus, the nitriding process can passivate the FSG film deeper than a via depth.

Abstract: A composition for production of silica glass using a sol-gel process is described, comprising silica particles, a dispersing agent, and a solution containing a polymerizable monomer for formation of acrylic resin and a crosslink agent dissolved in distilled water. The polymerizable monomer is n-methylol acrylamide or n-methylol methacrylamide. A method for production of silica glass is described, including the step of adding silica particles and a dispersing agent to a premix solution of the polymerizable monomer for formation of acrylic resin and the crosslink agent dissolved in distilled water.

Abstract: A continuous fiber of titania are made having an average diameter per a monofilament of from 5 to 50 &mgr;m, which has a BET specific surface area of 10 m2/g or more, a pore volume of 0.05 cc/g or more, a volume of pores having a pore diameter of not less than 10 angstroms being 0.02 cc/g or more and an average tensile strength per a monofilament of 0.1 GPa or more, or which has an average tensile strength per a monofilament of 0.5 GPa or more.

Abstract: An opaque silica glass article comprising a transparent portion and an opaque portion, wherein the opaque portion has an apparent density of 1.70-2.15 g/cm3 and contains 5×104-5×106 bubbles per cm3, said bubbles having an average diameter of 10-100 &mgr;m; and the transparent portion has an apparent density of 2.19-2.21 g/cm3 and the amount of bubbles having a diameter of at least 100 &mgr;m in the transparent portion is not more than 1×103 per cm. The opaque silica glass article is made by a process wherein a mold is charged with a raw material for forming the opaque portion, which is a mixture comprising a silica powder with a small amount of a silicon nitride powder, and a raw material for forming the transparent portion so that the two raw materials are located in the positions corresponding to the opaque and the transparent portions, respectively, of the silica glass article to be produced; and the raw materials are heated in vacuo to be thereby vitrified.

Abstract: A method for fabricating a rib on a glass substrate includes steps of printing a first paste layer on the glass substrate, printing a second paste layer onto a first predetermined area of the first paste layer and the second paste layer having a hardener, activating the hardener of the second paste layer to harden the second paste layer, performing a stripping process to remove a portion of the first paste layer uncovered by the hardened second paste layer, and sintering the remaining first paste layer and the second paste layer to form the ribs. The first paste layer is formed by a solid printing process and the second paste layer is formed by a screen printing process. The second paste layer is a rib material having a photo-active hardener, such as polyvinyl cinnamate. The hardener of the second paste layer is activated by an exposure process. Finally, the hardener is removed from the second paste layer in the sintering process and the first paste layer is fused to the second paste layer.

Abstract: A method for producing composite ceramic material is provided wherein a core ceramic structure is produced and simultaneously enveloped with a sleeve of similar material.

Abstract: A process for producing Mn—Zn ferrite having large electrical resistance and being durable to the use in high frequency region exceeding 1 MHz easily and at low cost is disclosed. The process comprises pressing a mixed powder comprising a composition of 44.0 to 50.0 mol % of Fe2O3, 4.0 to 26.5 mol % of ZnO, 0.1 to 8.0 mol % of at least one member selected from the group consisting of TiO2 and SnO2, and the remainder being MnO, and if desired 0.1 to 16.0 mol % of CuO, sintering the resulting green compact in the air or an atmosphere containing an appropriate amount of oxygen, and then cooling the green compact, thereby securing the estimated high initial permeability even in a high frequency region of 1 MHz or more.

Abstract: The present invention provides a process for preparing a raw material powder for producing a sintered body of aluminum titanate comprising: pulverizing a mixture containing: (1) 100 parts by weight of aluminum titanate crystals pulverized until a maximum grain size of 30 to 50 &mgr;m is attained; and (2) 2 to 6 parts by weight of spinel crystals obtained by heating a mixture containing MgO and Al2O3 at 1250° C. to 1290° a molar ratio of MgO to Al2O3 being 1:0.95 to 1:1.05, said pulverizing being conducted by wet grinding process with a ball mill or cylinder mill.

Abstract: In many engineering production processes, for example glass or glass-ceramic manufacturing processes, liquids, such as glass melts, participate in the processes in which gases are dissolved, which in part form bubbles in the liquid. So that the quality of the final product is not disadvantageously influenced, the liquid, e.g. glass melt, should be refined to remove the bubbles. According to the method of the invention an overpressure acting on the liquid is provided which is such that the internal pressure in the bubbles immediately under the surface of the liquid in a refining chamber is at least as great as the sum of equilibrium pressures of the gases dissolved in the liquid and the sum of the vapor pressure of components evaporating from the liquid. A two stage apparatus is provided which performs a preferred embodiment of the refining method of the invention.

Abstract: A gas is supplied to the surface of the glass sheet transferred between a heating furnace and a cooling apparatus for tempering the glass sheet. The gas is supplied from the upstream side with respect to the direction of transfer of the glass sheet by an air curtain device. This gas runs along the glass sheet surface (upper surface) downstream with respect to the direction of transfer to obstruct the flow of cooling gas from the cooling apparatus in the upstream direction. The gas prevents cooling air from the cooling apparatus from invading the heating furnace so that the difference of the curvature of the glass sheet on the front and rear part can be eliminated.

Abstract: The invention provides a method for the manufacture of a dental restoration including the steps of forming a model of refractory material of a tooth, and forming, by flame spraying directly on to said refractory model, a base layer of predetermined thickness of said restoration, said refractory model being cooled during the formation of said base layer. The refractory model is subjected to burn out, and optionally hardening heat treatment, and one or more layers of dental porcelain are applied to the base layer following sintering of said base layer.

Abstract: Exemplary silicon carbide ceramic bodies having inclusions therein are produced according to the invention. An exemplary ceramic body includes silicon carbide in major amounts and unreacted particles of an additive in minor amounts which are bonded to the matrix. The particles are dispersed throughout the silicon carbide, and are preferably selected from one or more of the group consisting of boron nitride, aluminum nitride and titanium diboride.

Abstract: A continuous rod with a composite filler having a core constituting a small-diameter cigarette rod and a tube surrounding the core and being confined within a converted web of cigarette paper has axially spaced-apart densified sections in the core as well as in the tube. When the continuous rod is converted into a series of discrete cigarettes, it is severed simultaneously across the densified sections of the core as well as across the densified sections of the tube. If the densified sections of the core are not confined within the densified sections of the tube, a trimming device of the maker of the core is adjusted to shift the locations of the thereafter formed densified sections of the core until such densified sections register with those of the tube.

Abstract: A method of making a product which is generally impervious to water including the steps of making a generally homogenous mixture of slate particles and clay, setting the mixture as necessary to produce a formable composition, forming the wet mixture to a desired configuration, at least partially drying the formed mixture and subjecting the dried formed mixture to a temperature of at least 1145° C. for a time sufficient for at least some of the clay to convert into a binder to bind together the slate particles.

Abstract: Disclosed is a sol-gel process for making high-density monolithic alpha-alumina articles. Cracking problems caused by shrinkage of the gel during the drying and firing stages are minimized by controlling the temperature and humidity during the drying process and by using molds formed of prescribed polymeric materials, preliminarily coated with a silicone release agent. The process of the invention provides porous alpha-alumina articles having a controlled microstructure and a controlled pore size distribution, which are beneficial features when the material is used in practical applications, e.g., as substrates for gas sensors.