Abstract: New sealant compositions for sealing end closures or inleads in ceramic envelopes are based on the system Dy.sub.2 O.sub.3 -Al.sub.2 O.sub.3 -SiO.sub.2. These compositions will withstand metal halides used as arc materials up to temperatures exceeding 1200.degree. C, and make possible more efficient lamps of improved color rendition.

Abstract: A method of making improved SIALON ceramics without the need for hot pressing, is disclosed. A homogeneous slip is prepared from Si.sub.3 N.sub.4, Al.sub.2 O.sub.3 and Y.sub.2 O.sub.3 in the presence of a suspension agent; Y.sub.2 O.sub.3 being present in at least 1% by weight (preferably between 1-25%) and Al.sub.2 O.sub.3 being present in the range 16-40% by weight (preferably 16-18%). The slip is cast and dehydrated. The cast shape is reaction sintered at about 1550.degree.-1700.degree. C (preferably 1600.degree. C) for no less than 3 hours (preferably between 3-12 hours).

Abstract: Ceramics having nonlinear voltage characteristics in which (1) zinc oxide is used as a main component and (2) praseodymium, (3) one or more of magnesium or calcium, and (4) cobalt are added thereto as subcomponents, in elemental form or as a compound thereof, in an amount of from about 0.08 to about 10.0 atomic % for praseodymium, from about 0.08 to about 10.0 atomic % for the one or more of magnesium or calcium, and from about 0.1 to about 8.0 atomic % for the cobalt, each calculated as praseodymium, magnesium or calcium and cobalt.

Abstract: A sintered ceramic dielectric body is provided which exhibits a high dielectric constant as well as a low dielectric loss and almost no variation in the dielectric constant and the dielectric loss with respect to a wide variation of an applied high AC or DC voltage, respectively. The ceramic dielectric composition consists essentially, by weight, of approximately 18 to 70% of strontium titanate (SrTiO.sub.3), approximately 4 to 75% of barium titanate (BaTiO.sub.3), 2.5 to 17.4% of bismuth oxide (Bi.sub.2 O.sub.3) and 1.7 to approximately 20% of titanium oxide (TiO.sub.2); the ratio by mole of the titanium oxide (TiO.sub.2) to the bismuth oxide (Bi.sub.2 O.sub.3) being within the range from approximately 1 to 18.

Abstract: A ceramic compound having the formula (La.sub.x A.sup.+2.sub.1-x).sub.2 (Ti.sub.x B.sup.+5.sub.1-x).sub.2 O.sub.7 wherein A.sup.+2 is a positive divalent element selected from the group consisting of Ba, Ca, Cd, Mg, Sr and mixtures thereof and B.sup.+5 is a positive pentavalent element selected from the group consisting of Sb, Mo, Nb, Ta, W and mixtures thereof and x is a numeral ranging from 0.70 to 0.99. This compound is characterized by a relatively small temperature coefficient of permittivity, a relatively high insulation resistance, a relatively low loss factor and is compatible with relatively low cost noble metals, making it useful for forming dielectric elements in monolithic multi-layer capacitor elements.

Abstract: Disclosed is a silicon nitride-based sintered material having high heat resistance and containing crystal compounds prepared from the silicon nitride and at least one of oxides of the elements belonging to the III A group in the periodic table.

Abstract: Multiple oxides of the general formula (L.sub.1 -x Mx) (Q.sub.1 -y Ry)O.sub.3, in which L is an element of atomic number 57 - 71, M is an element of Ca, Sr or Ba, Q and R are mutually different elements of atomic number 21 - 30 or Zr, 0 .ltoreq. x < 1 and 0 < y < 1, have excellent electron-conductivity and thermal stability.

Abstract: This ceramic composition is produced from a mixture of yttrium oxide and heavy rare earth oxides having an atomic number of from 64-71 in selected proportions for the construction of crucibles and the lining of molds employed in making castings of reactive metals, such as titanium and alloys thereof. The elements utilized in the composition impart a minimum of contamination to the molten metal during the melting and casting phases and are produced from an ore with only the refinement steps necessary so as to secure maximum economy and yet insure the production of castings of the highest quality.

Abstract: Silicon nitride based refractory articles with flexural strengths at room temperature of up to 150,000 p.s.i. and at 1375.degree. C of up to about 117,000 p.s.i. result when mixtures of 80 to 98.5% by weight of silicon nitride, 1 to 15% by weight of yttrium oxide, and 0.5 to 10% by weight of thorium oxide are pressure sintered according to conventional methods.

Abstract: A ceramic having non-linear voltage characteristics, comprising the product obtained on mixing (a) zinc oxide, as a principal component, and (b) (1) cobalt and (2) one of neodymium, samarium or dysprosium, either in an elemental form or as a compound thereof, each in an amount of 0.1 to 10 atomic % for the cobalt, neodymium, samarium and dysprosium, calculated as cobalt, neodymium, samarium and dysprosium as subcomponents, and calcining the mixture at a temperature of from about 1150.degree. to about 1400.degree. C.

Abstract: Disclosed is a solid diffusion source for the phosphorus doping of semiconductors, which comprises a substance composed of at least one kind of compound R.sub.2 O.sub.3 selected from the group consisting of Y.sub.2 O.sub.3, La.sub.2 O.sub.3 and Ce.sub.2 O.sub.3 and P.sub.2 O.sub.5 and containing mainly a compound with a chemical formula R.sub.2 O.sub.3.5P.sub.2 O.sub.5.

Abstract: Ceramics having nonlinear voltage characteristics comprising the product obtained on preparing a mixture of zinc oxide as a main component, and, as subcomponents, cobalt plus one of praseodymium or terbium, either in an elemental form or as a compound thereof, in an amount of from 0.1 to 8.0 atomic % for the cobalt, from 0.08 to 8.0 atomic % for the praseodymium and from 0.1 to 8.0 atomic % for the terbium, each calculated as cobalt, praseodymium and terbium, and calcining the mixture at a temperature in the range of from about 1150.degree. to about 1400.degree. C and a method for preparing the ceramics. An embodiment includes, as an additional subcomponent, lanthanum, either in an elemental form or as a compound in an amount of from 0.08 to 8.0 atomic %, calculated as lanthanum, with the zinc oxide, cobalt and praseodymium.

Abstract: A rare earth ceramic having a microcrystal phase buried in a glassy phase for the coversion of radiation in the near-infrared band from about 0.85 to 1.06 um into visible light. It comprises a mixture of lead fluoride PbF.sub.2, ytterbium oxide Yb.sub.2 O.sub.3, at least one glass-forming oxide selected from the oxides of B, Si, P, Ge, Te, and at least one compound of a rare earth doping element chosen as a function of the desired emission color, i.e.A compound containing thulium ions Tm.sup.3.sup.+ for a blue emission mixture;A compound containing erbium ions Er.sup.3.sup.+ for a green emission mixture;A compound containing holmium ions Ho.sup.3.sup.+ for a green emission mixture;A compound containing erbium ions Er.sup.3.sup.+ for a red emission mixture, whereby the oxygen ions from the oxides are exclusively located in the glassy phase while ytterbium and the rare earth are exclusively located in the microcrystal phase.

Abstract: A ceramic dielectric material according to the present invention has a composition consisting essentially of La.sub.2 Ti.sub.2 O.sub.7, Sr.sub.2 Nb.sub.2 O.sub.7, and 1/2Mg.sub.2x --Ti.sub.2.sub.-2x O.sub.4.sub.-2x, where x lies in a range of 0 to 1.0. This material has a relatively large dielectric constant, a very stable temperature coefficient of the dielectric constant over a wide temperature range, a widely controllable value of the temperature coefficient of the dielectric constant, and a small dielectric loss. The temperature coefficient of the dielectric constant can be determined optionally in a wide range of value by simply changing the ratios among the three constituents of the composition.

Abstract: A ceramic dielectric composition is provided including 30 to 94% by mol of SrTiO.sub.3, 1 to 22% by mol of Bi.sub.2 O.sub.3 and 5 to 69% by mol of TiO.sub.2, and further including 0.1 to 20% by weight of MgO with respect to the total weight of the above-mentioned three compounds SrTiO.sub.3, Bi.sub.2 O.sub.3 and TiO.sub.2, whereby the ceramic dielectric composition has a high dielectric constant and a low dielectric loss and further the variations of the dielectric constant and the dielectric loss with respect to the variation of an applied voltage, are respectively, very small.

Abstract: Multifocal photochromic opthalmic lenses are produced by nucleating potentially photochromic major lens blanks through heat treatment, combining the nucleated blanks with compatible button or segment glasses, and fusing the combined glasses at temperatures suitable for achieving both fusion and the simultaneous development of full photochromic properties in the previously nucleated major lens blanks.

Abstract: New compositions of matter each consisting essentially of a solid solution of compounds and a halide binder aid. The novel compositions have melting points above 1800.degree. C, high mechanical integrity, low thermal conductivity, and are essentially non-reactive with molten reactive and refractory metals. The novel compositions sinter at 1000.degree. to 1300.degree. C.

Abstract: Hot conductors containing a mixture of neodymium oxide and samarium oxide are suitable for use at high temperatures.

Abstract: Hot conductors containing a mixture of terbium oxide and erbium oxide are suitable for use at high temperatures.

Abstract: Hot conductors containing a mixture of praseodymium oxide and erbium oxide are suitable for use at high temperatures.

Abstract: Hot conductors containing a mixture of neodymium oxide and gadolinium oxide are suitable for use at high temperatures.

Abstract: Hot conductors containing a mixture of cerium oxide and gadolinium oxide are suitable for use at high temperatures.

Abstract: A ceramic material characterized by a high degree of resistance to failure by thermal fracture which comprises a composite of a refractory oxide and flaked boron nitride. The boron nitride flakes are incorporated into a refractory oxide matrix as an inert, nonreactive, uniform dispersed phase in proportions sufficient to provide the oxide composite with an increased resistance to thermal shock.

Abstract: An improved reduction-reoxidation type semiconducting ceramic capacitor and the method for producing the same are disclosed. The main components of the substrate of the capacitor are CaTiO.sub.3, SrTiO.sub.3 and Bi.sub.2 O.sub.3.xTiO.sub.2. Said substrate also contains at least one member selected from the group consisting of manganese, cobalt, nickel, chromium, vanadium, niobium, tantalum, lanthanum and cerium ions in total amounts of 0.025 to 0.4% by weight. The capacitor according to the present invention excels, in the temperature independency of the capacitance and tan .delta., etc.

Abstract: Ceramic bodies coated or joined to one another with ceramic eutectic compositions of alumina, silica and rare earth oxides melting below 1600.degree. C are described. An exemplary composition contains about 20 weight percent alumina, 58 weight percent silica, and 22 weight percent yttria. Composite structures of such bodies exhibit good to excellent thermal shock resistance, resistance to chemical attack, and joint strengths between bodies and coatings or between various silica, alumina and rare earth oxide based ceramics joined together or to each other.

Abstract: We had previously disclosed a heat resistive and reinforced composite material which was prepared by sintering a finely powdered mixture of trisilicon tetranitride and an oxide of yttrium group elements.More improved similar composite material having excellent bending strength can be obtained by sintering a finely powdered mixture of trisilicon tetranitride, yttrium oxide and aluminum oxide. Cerium oxide, lanthanum oxide or scandium oxide can also be used instead of yttrium oxide.

Abstract: An electrical discharge device and in particular a low voltage or shunt-type igniter plug is disclosed, said plug having a beryllium oxide ceramic insulator disposed between the center electrode firing tip and the ground electrode, said insulator having a novel semi-conducting metal oxide coating formed thereon to provide an ionized path along which spark discharge between said electrodes occurs.

Abstract: A dense barium borosilicate glass is disclosed having a refractive index greater than 1.64 and a dispersive index of at least 53, together with a high degree of chemical durability such that optical blanks molded from the glass can be finished on automatic machinery with minimal danger of staining. The glass consists essentially of 18-30% SiO.sub.2, 8-22% B.sub.2 O.sub.3, 25-48% BaO, 0-10% other divalent metal oxides, 25-45% total divalent metal oxides, 10-30% La.sub.2 O.sub.3, 0-6% ZrO.sub.2 and/or SnO.sub.2, with the mole ratio of BaO:SiO.sub.2 not exceeding 0.6 and preferably not exceeding 0.5.

Abstract: A pump member for molten metal manufactured from a sintered mass including aluminium nitride as a major component and 0.1 to 10% by weight of at least one oxide selected from the group consisting of oxides of Group IIIA elements of the Periodic Table.