Abstract: Ceramic decalcomania for the production of overglaze decorations on ceramic ware which include, in addition to the design layer, two separate layers of powdered glass acting in combination during firing to seal off corrosive glass-pigment interactions and provide fired decorations of improved detergent durability are described.

Abstract: An apparatus is disclosed for drawing glass optical waveguide filaments having minimal diameter variation. A draw blank is supported within an elongated, heated, tubular muffle which heats the blank to its draw temperature. Gas is supplied to that end of the muffle opposite that from which the filament is drawn. A cylindrically shaped member at least 10 cm long is disposed adjacent to the end of the blank opposite the filament to form with the inner wall of the muffle a thin, cylindrically-shaped channel through which the gas must flow. The gas stream is thus uniformly heated at the time that it reaches the root of the filament so that diameter variations due to gas turbulence are minimized.

Abstract: This invention is directed to the production of glass-ceramic articles having compositions within the Li.sub.2 O-Al.sub.2 O.sub.3 -SiO.sub.2 field nucleated with a combination of TiO.sub.2 + ZrO.sub.2 wherein beta-spodumene solid solution constitutes the primary crystal phase. Mullite and/or corundum along with ZrTiO.sub.4 solid solution and, occasionally, ZrO.sub.2 solid solution are present as secondary crystal phases. Because of their low coefficients of thermal expansion and exceptional long time dimensional stability at temperatures up to 1000.degree. C., the compositions can be useful in applications where extreme changes in temperature are experienced; for example, the construction of honeycomb structures used in regenerative heat exhchangers for turbine engines.

Abstract: A heat exchange element, particularly suitable for use as a recuperator for external combustion engines or other multiple fluid flow path body, may be produced as a monolithic, ceramic, honeycombed body having a plurality of flow paths therethrough for two or three fluids wherein multiple flow paths of separate fluids are separated by walls which may be less than 10 mils thick.The honeycombed ceramic body is provided with a plurality of open-ended cells extending from one face end to another face end and arranged in vertical columns of cells separated by vertical fluid barrier wall surfaces. Selected columns of open-ended cells are closed on both face ends of the body and entrance to and exit from the selected cells is provided by removing portions of cell walls near face ends of the body between fluid barrier wall surfaces.

Abstract: A solar simulator comprising an SnO.sub.2 -containing glass ultraviolet absorption filter in combination with a xenon arc light source, which simulator closely approximates the characteristics of the terrestrial solar spectrum at violet and ultraviolet wavelengths, is described.

Abstract: A method for purifying a spent hydrofluoric acid etching solution containing siliceous by-products which comprises treating the solution with a weak anion exchange resin of the polyamine type to remove SiF.sub.6.sup.= ions therefrom is described. The anion exchange resin may be regenerated with aqueous NaOH.

Abstract: The absorptive and refractive properties of additively colored glasses containing an absorptive metallic silver phase and a separated silver halide phase are altered by irradiating the colored glasses with visible light. Polarization effects and multicolored images can be produced.

Abstract: Silver halide-containing photochromic glasses are rendered optically anisotropic by darkening with actinic radiation and irradiating with linearly polarized bleaching light. A photochromic glass so treated will be optically isotropic when it returns to the clear state, but may again become optically anisotropic when redarkened. Color adaptation results when darkened silver halide-containing photochromic glasses are irradiated with colored optical bleaching light.

Abstract: This invention relates to the production of chemically durable inorganic silicate coatings which are homogeneous, easy to apply, and exhibit essentially infinite shelf life. More specifically, this invention relates to the preparation of such coatings by incorporating a metal oxide (M.sub.x O.sub.y) wherein Y:X is at least 1.5, into a true aqueous solution of an alkali metal silicate, at least about 50% by weight of said alkali metal consisting of potassium, which will dry in air, i.e., be non-hygroscopic. Thereafter, upon drying and curing, a crystal phase precipitates in situ within the solution causing polymerization of the silica at the crystal interfaces and subsequently throughout the solution, thus yielding a durable coating consisting essentially of a crystal phase homogeneously dispersed in a silicate glassy matrix.

Abstract: A generally concave reflector member is provided with three or more bosses having flat outer surfaces. The surfaces define a plane perpendicular to the axis of the parabola so that specific points within the parabola can be located with great precision. By using the bosses as reference points, lamp filaments can be accurately placed within the lamp structure, regardless of variations in the reflector member which occur during the manufacturing process.

Abstract: Fired refractory articles are made of a shaped refractory composition predominantly comprising grain of fusion-cast AZS refractory having: (i) a three-phase microstructure of interlocking crystals of corundum (alpha alumina) phase and baddeleyite (zirconia) phase with intercrystalline glassy phase therebetween, the glassy phase being about 15-30 vol.% of the AZS refractory, and (ii) an oxide analysis consisting of 35-60 wt.% Al.sub.2 O.sub.3 plus Cr.sub.2 O.sub.3 with Cr.sub.2 O.sub.3 .ltoreq. 60 wt.% of Al.sub.2 O.sub.3 plus Cr.sub.2 O.sub.3, 25-50 wt.% ZrO.sub.2, 10-18 wt.% SiO.sub.2, 0.8-1.8 wt.% Na.sub.2 O plus K.sub.2 O, and up to 0.7 wt.% other ingredients (e.g. impurities). Refractory composition consists of: (A) 25-60 wt.% fusion-cast AZS refractory coarse grain being at least 89 wt.% -6+20 Tyler mesh, (B) 0-38 wt.% fusion-cast AZS refractory medium grain being at least 73 wt.% -10+35 Tyler mesh, and (C) 30-50 wt.% at least one component selected from the group consisting of: (1) 0-50 wt.

Abstract: The instant invention is related to the production of glass-ceramic articles which exhibit a hydrophobic character and an inherent tactile quality of being slippery or oily to the touch. Such articles are dervived from compositions within the MgO--Al.sub.2 O.sub.3 --SiO.sub.2 --F quaternary and contain the humite mineral norbergite (Mg.sub.2 SiO.sub.4. MgF.sub.2) as a major crystal phase. The intrinsic hydrophobic character and lubricity of the inventive compositions recommend their utility in such applications as (1) high temperature bearing or other low friction mechanical devices, an (2) non-sticking and easily-cleaned culinary ware.

Abstract: The present invention primarily comprises an improvement upon the method for producing photosensitive colored glasses or polychromatic glasses utilizing two sequences of exposure to high energy or actinic radiation followed by heat treatment. The invention contemplates replacing the second exposure/heat treatment step with a heat treatment conducted in a reducing atmosphere at a temperature of at least 350.degree. C., but below the strain point of the glass. The resultant articles can be particularly useful in ophthalmic applications.

Abstract: An analyzer for electrophoretic samples includes a sensor of extremities, more particularly valleys, in the output from the detector. The analysis of electrophoretic samples includes integration of the area under each of the fractions of the multicomponent output. In order to integrate each of the components, it is necessary to detect valleys in the output. The detector output is first applied to a non-linear processor such as a logarithmic amplifier and a differentiator. The logarithmic amplifier changes the shape of the output to make the detection less dependent upon relative component amplitude. A threshold comparator produces a pulse when the slope of the analyzer output, as represented by the output of the differentiator, exceeds a threshold. The threshold is changed after the detection of the first valley. Noise suppression circuitry prevents the detector from responding to closely occurring extremities in the analyzer output.

Abstract: An extrusion die for forming a honeycomb structure having a plurality of interconnected discharge slots provided with a plurality of relatively small sized feed holes directly communicating with intersecting portions of said discharge slots, and a plurality of relatively larger feed passageways each communicating with a plurality of said relatively small sized feed holes, with said feed holes and feed passageways extending longitudinally of said die and the flow through said die such that a portion of such flow may pass directly through such die in a linear path.

Abstract: A solar energy collector structure has been provided which comprises a plurality of at least partially evacuated tubular members arranged in a group and closely packed in parallel axial alignment. The tubular members are joined together to form a tube sheet. A pair of such tube sheets are placed in tandem with a pair of opposite margins thereof being sealed, one to the other, to form a flow channel therebetween. An absorber, disposed between the tube sheets, in the flow channel, intercepts and absorbs solar energy, which by heat transfer is carried off by a working fluid in the heat exchange relation with the absorber surface.

Abstract: A process for producing transparent high-annealing-point 96% silica glass comprising the steps of depositing a carbon film on the pore walls of the glass, heating the glass and film under non-oxidizing conditions, and removing the carbon film by oxidation, is described.