Abstract: Inorganic crystals having one or more species of dopant ions which are photo-reactive are used as visible and or infrared light optical limiters to protect against laser radiation exposure while permitting passage of the visible and or infrared light spectrum at least until exposed to high energy laser radiation. The dopant ions are selected from ions of transition metals. The exposure of these ions within the transparent crystalline matrix either photo-ionize or are elevated to an excited state and thereby absorb or otherwise attenuate the passage of the laser beam radiation sufficiently to protect human eyes or photo-sensitive equipment. The crystals may be fabricated into such items as lenses for use in eyeglasses or on shields of flight helmets to protect the eyes of aircraft pilots.

Abstract: A semiconductor ceramic device includes a semiconductor ceramic sintered body and external electrodes. The semiconductor ceramic sintered body contains a lanthanum cobalt type oxide major component, about 0.1 to 10 mol % on an element conversion basis of an oxide of Cr as a sub-component, and about 0.001 to 0.5 mol % on an element conversion basis of at least one of the oxides of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ni, Cu and Zn.

Abstract: Negative thermal expansion materials, methods of preparation and uses therefor are disclosed. The materials are useful for negative thermal expansion substrates, such as those used for optical fiber gratings.

Abstract: A multi-phase solid electrolyte ion transport membrane comprising at least two phases wherein one of the phases comprises an oxygen ion single conductive material, or a mixed conductor. The other phase comprises an electronically-conductive metal or metal oxide that is incorporated into the membrane by deposition of the metal or metal oxide from a polymer made by polymerizing a chelated metal dispersion in a polymerizable organic monomer or prepolymer. The multi-phase composition advantageously comprises a first phase of a ceramic material and a second phase of a metal or metal oxide bound to a surface of the ceramic material. The multi-phase composition is advantageously prepared in an in-situ fashion before fabricating the membrane matrix. As another alternative, a preformed ceramic matrix is surface-coated with a metal or metal oxide.

Abstract: A ceramic compound which undergoes martensitic transformation comprises a compound represented by compositional formula Ln1-xSixAlO3+0.5x obtained by substituting a part of LnO1.5 in LnAlO3-type compounds with SiO2, where Ln represents at least one element selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb, and x=0.01 to 0.3.

Abstract: A layer crystal structure oxide, and memory element comprising same, comprising bismuth (Bi), a first element, a second element and oxygen (O), wherein the first element is at least one selected from the group consisting of sodium (Na), potassium (K), calcium (Ca), barium (Ba), strontium (Sr), lead (Pb), and bismuth (Bi), the second element is at least one selected from the group consisting of iron (Fe), titanium (Ti), niobium (Nb), tantalum (Ta), and tungsten (W), and the composition ratio of the bismuth with respect to the second element is larger than the stoichiometric composition ratio, wherein, the composition ratio of the bismuth with respect to the first element is in the range of (2±0.17)/(m−1) including the stoichiometric composition ratio 2/(m−1), where m is an integer from, and including, 2 to 5.

Abstract: The invention is a sol-gel processed metal-aluminum based oxide material useful as a catalyst including a NOx trapping catalyst. It is made from alkoxides comprising heterometallic alkoxides. The metal is transition metal, one or both of alkali metal and alkaline earth metal, and optionally also a lanthanide. Then invention is also a method of treating lean-burn internal combustion engine exhaust gas with this material, without any precious metal included with the material, in the exhaust gas system. The method comprises locating the NOx trap in the system where the NOx trap absorbs nitrogen oxides during lean cycle operation and desorbs the nitrogen oxides when the concentration of the oxygen in the exhaust gas is lowered as during a rich or stoichiometric cycle.

Abstract: Mixed oxides excellent in thermal stability of specific surface area and in oxidation-reduction performance are provided on an industrial scale. Catalyst materials useful in exhaust gas purification are also provided. The invention is concerned with mixed oxides containing cerium, zirconium and sulfur, namely cerium- and zirconium-based mixed oxides having the composition: 50 to 79% by weight as cerium oxide, 20 to 49% by weight as zirconium oxide, and 1 to 5% by weight as sulfate (SO.sub.4). The invention also relates to a method of producing cerium- and zirconium-based mixed oxides which comprises mixing a cerous-alkali metal sulfate double salt with a zirconium ion-containing solution and then adding a base to the mixed solution to thereby cause formation of a precipitate. The invention further relates to catalyst materials for exhaust gas purification which comprise a mixed oxide containing cerium, zirconium and sulfur, namely a cerium- and zirconium-based mixed oxide containing sulfur in an amount of 0.

Abstract: Sintered ITO having a relative density of at least 88% and an oxygen content of 15.5-17.0 wt %, as well as an ITO sputtering target made of this sintered ITO. Using the target, an optimal range for the proportion of oxygen in a mixture of argon and oxygen gases used as a sputtering atmosphere is sufficiently expanded to permit the consistent formation of ITO films.

Abstract: A ceramic composite containing alkali-metal-.beta.- or .beta."-alumina and an oxygen-ion conductor is fabricated by converting .alpha.-alumina to alkali-metal-.beta.- or .beta."-alumina. A ceramic composite with continuous phases of .alpha.-alumina and the oxygen-ion conducting ceramic, such as zirconia, is exposed to a vapor containing an alkali-metal oxide, such as an oxide of sodium or potassium. Alkali metal ions diffuse through alkali-metal-.beta.- or .beta."-alumina converted from .alpha.-alumina and oxygen ions diffuse through the oxygen-ion conducting ceramic to a reaction front where .alpha.-alumina is converted to alkali-metal-.beta.- or .beta."-alumina. A stabilizer for alkali-metal-.beta."-alumina is preferably introduced into the .alpha.-alumina/oxygen-ion conductor composite or introduced into the vapor used to convert the .alpha.-alumina to an alkali-metal-.beta."-alumina.

Abstract: An improved highly oxygen permeable substrate is provided comprising Sr--Fe--Co-oxide and a metal combined with said material. Also provided is a method for producing an improved membrane to facilitate oxidation of compounds comprising combining metal or metal alloys with Sr--Fe--Co-oxide to create a mixture, and sintering the mixture so as to allow the metal to melt within the mixture. The membrane is also utilized in a method for converting methane to syngas whereby a fluid containing oxygen is contacted to a first surface of the membrane for a sufficient period of time so as to cause some of the oxygen to be transported to a second surface of the membrane; and contacting methane to the second surface for a sufficient period of time to cause oxidation of the methane.

Abstract: A two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion. The dehydrogenation portion is a group VIII metal and the oxide-ion conducting portion is selected from a ceramic oxide crystallizing in the fluorite or perovskite structure. There is also disclosed a method of forming a hydrogen rich gas from a source of hydrocarbon fuel in which the hydrocarbon fuel contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion at a temperature not less than about 400.degree. C. for a time sufficient to generate the hydrogen rich gas while maintaining CO content less than about 5 volume percent. There is also disclosed a method of forming partially oxidized hydrocarbons from ethanes in which ethane gas contacts a two-part catalyst comprising a dehydrogenation portion and an oxide-ion conducting portion for a time and at a temperature sufficient to form an oxide.

Abstract: The present invention provides magnetostrictive compositions that include an oxide ferrite which provides mechanical properties that make the magnetostrictive compositions effective for use as sensors and actuators.

Abstract: The present invention provides a ceramic sintered body excellent in oxidation resistance under high temperatures and markedly superior to the conventional ceramic sintered body in the mechanical strength over a wide temperature range of between room temperature and 1,500.degree. C. The ceramic sintered body of the present invention comprises at least one ceramic crystal grain selected from the group consisting essentially of a monosilicate represented by the general formula RE.sub.2 SiO.sub.5, where RE denotes a IIIa group element including yttrium, and a disilicate represented by the general formula RE.sub.2 Si.sub.2 O.sub.7, where RE denotes a IIIa group element including yttrium, and at least one additional element selected from the group consisting of Al, Cr, Hf, Nb, Zr, Ti, V, Ta, Ca and Mg which is segregated in the boundaries of the ceramic crystal grains in an amount of 0.1 to 15% by weight of the sintered body in terms of the oxide thereof.

Abstract: An oxide ion mixed conductive substance has the formula of A.sub.1-x Ca.sub.x Ga.sub.1-y B.sub.y oxide, wherein A is at least one lanthanoid element having a trivalent octacoordinated ion radius of 1.05 to 1.15 .ANG., B is at least one element selected from the group consisting of Co, Fe, Ni and Cu, x is 0.05 to 0.3, y is 0.05 to 0.3. The oxide ion mixed conductive substance has the perovskite structure.

Abstract: A semiconductive ceramic composition having negative resistance-temperature characteristics, wherein the composition comprises lanthanum cobalt oxide as the primary component, and, as secondary components, at least one oxide of an element selected from B, Fe and Al and at least one oxide of an element selected from Si, Zr, Hf, Ta, Sn, Sb, W, Mo, Te, Ce, Nb, Mn, Th and P. A semiconductive ceramic composition having a resistivity of approximately 10 .OMEGA..multidot.cm to 100 .OMEGA..multidot.cm at room temperature is obtained by controlling the amount of additives. Since the resistivity at room temperature can be enhanced to several times or more that of the conventional compositions while characteristics of the conventional compositions are maintained, the composition may be widely applied to control heavy current.

Abstract: A method is provided for forming a molten oxide ceramic electrode for a plasma arc ignited between first and second electrodes within a plasma arc chamber, wherein the conductivity the oxide ceramic is a function of temperature alone. Following ignition of the plasma arc, a mixture is formed of a small quantity of molten oxide ceramic and a sufficiently high concentration of a volatile contaminant to render the mixture electrically conductive. The plasma arc is then transferred from one of the electrodes to the mixture. The temperature of the mixture is raised sufficiently to render the oxide ceramic electrically conductive. Finally, the volatile contaminant is progressively removed from the mixture so as to leave an electrode composed of substantially pure molten oxide ceramic.

Abstract: Inorganic media for barrel finishing produced by sintering a media green body formed from a mixed material comprising clay fine grains as a binder, abrasive grains and aluminum hydroxide fine grains as a brittleness imparting agent. The inorganic media is excellent in finishing performance, with which rough finishing can be conducted by dry barrel finishing.

Abstract: A semiconductive ceramic in which the B constant is maintained at about 4000 K or more at elevated temperature to thereby decrease power consumption, and the B constant is lowered less than 4000 K at low temperature so as to avoid unnecessary increase of resistance; as well as a semiconductive ceramic element using the same. The semiconductive ceramic is formed of a lanthanum cobalt oxide, which serves as the primary component, and, as a secondary component, at least one oxide of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba, Ni, Cu and Zn. The semiconductive ceramic element is fabricated through use of the semiconductive ceramic and an electrode formed thereon.

Abstract: A filler for a sliding gate containing 70 to 90 wt % of chromite sand and 10 to 30 wt % of silica sand in which the particle size distribution of the chromite sand is substantially from 500 to 1,000 .mu.m, which is not melted, sintered or penetrated by molten metal (molten steel) poured in a ladle in a steel works, and therefore is easily discharged to let the gate through.

Abstract: A novel ceramic substrate useful for the preparation of superconducting films, said substrate having the formula REBa.sub.2 MO.sub.6 where RE represents rare earth metals--Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and M represents metals Nb, Sb, Sn, Hf, Zr; and a process for the preparation of superconducting YBa.sub.2 Cu.sub.3 O.sub.7-.delta. thick films on new ceramic substrate.

Abstract: A precursor solution for the preparation of metal phosphates is provided. Two components are prepared in which the first is a metal salt dissolved in alcohol, and the second component is phosphorous pentoxide dissolved in alcohol. The two components are mixed and may be applied as a liquid coating to a variety of substrates. The coated substrate is then heated, causing removal of all other components and leaving a layer of pure metal phosphate.

Abstract: A sintered ITO compact is provided which is capable of retarding nodule formation, or particle generation. The sintered ITO compact is composed of In, Sn, and O, and has avelage length of void size of not larger than 0.7 .mu.m. This sintered ITO compact is produced by sintering, substantially in an oxygen atmosphere, a green compact formed from a mixed powder of indium oxide power and tin oxide powder, the mixed powder containing the tin oxide powder at a content ranging from 5% to 15%, and the tin oxide powder having particles of a particle size of not more than 1 .mu.m constituting not less than 90% portion thereof; or produced by sintering, in an oxygen atmosphere, a green compact formed from a mixed powder of indium oxide powder and tin oxide powder, the mixed powder having a tap density of not less than 1.8 g/cm.sup.3, and the tin oxide powder having a maximum particle size of not larger than 1 .mu.m and a median diameter of not larger than 0.4 .mu.m.

Abstract: A process for making a crystalline solid-solution powder which involves reacting at least two reactants in a plasma arc of a plasma chamber and blast-cooling the resultant product in a high velocity gas stream to form the powder. The first reactant is a molten metal alloy and the second reactant is a gas. The reaction is carried out in a plasma arc and the products rapidly cooled by a gas stream acting at the outlet opening of the plasma chamber. The crystalline solid-solution powder formed by the process has a low electrical resistivity. If an indium-tin alloy is used as the first reactant and oxygen as the second reactant, there is obtained an indium-tin-oxide (ITO) crystalline solid-solution powder which, when compacted to 40% of its theoretical density, has an electrical resistivity in the range of about 2 .OMEGA.cm. This ITO crystalline solid-solution powder is particularly suitable for preparing an ITO target, with high electrical conductivity and thus high achievable sputtering rates.

Abstract: The present invention is ceramic article of stabilized zirconia wherein the stabilized zirconia has a molar ratio of rare earth oxide:zirconia of from 1:99 to 15:85, at a weight percent of from about 97 to 75. The ceramic article includes smectite clay from about 3 to 25 weight percent wherein the article is a mass of sintered particles having a continuous tetragonal phase having dispersed therein monoclinic phase particles having size of less than 100 nm.

Abstract: A ceramic composite material consisting of two or more crystal phases of different components, each crystal phase having a non-regular shape, said crystal phases having three dimensional continuous structures intertwined with each other, at least one crystal phase thereof being a single crystal. Further, by removing at least one crystal phase from this ceramic composite material, there is provided a porous ceramic material consisting of at least one crystal phase and pores, said crystal phase and pores having non-regular shapes and being three dimensionally continuous and intertwined with each other.

Abstract: The invention aims at providing highly reliable zinc oxide varistors through simple production steps. The varistor is produced by dispersing a powdery raw material comprising 1-40 molar % (in terms of Fe.sub.2 O.sub.3) iron, 0-20 molar % (in terms of Bi.sub.2 O.sub.3) bismuth, and the balance consisting of SiO.sub.2 in a solution of a water-soluble binder such as polyvinyl alcohol, and applying the formed dispersion to a molded or calcined zinc oxide varistor to form on the lateral face thereof a lateral high-resistance layer (2) containing Zn.sub.2 SiO.sub.4 as the principal ingredient and a solid solution of iron in Zn.sub.7 Sb.sub.2 O.sub.12 as the auxiliary ingredient.

Abstract: A carbon-graphite/silicon carbide composite article is provided. The composite article includes a carbon-graphite body intimately bonded to a dense silicon carbide body by a transition/bonding region which links the two bodies. The transition/bonding region between the carbon-graphite body and the silicon carbide body typically includes a layer rich in silicon metal and a small silicon carbide/silicon metal/carbon graphite area where some of the carbon-graphite from the carbon-graphite body has been converted to silicon carbide. The carbon-graphite body may also include a variety of impregnants.

Abstract: Scandium-substituted thallium manganese pyrochlore compounds having increased magnetoresistance compared to unsubstituted compounds are disclosed. Such compounds are suitable for use in magnetic read heads and provide the choice of resistivity range.

Abstract: Low or negative thermal expansion compounds are described having a formula of A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12. It currently is believed that y can vary from about 0 to about 2, x equals the sum of y and z and varies from about 0.1 to about 1.9. Without limitation, novel compounds satisfying the formula A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12 where y=0 may be selected from the group consisting of Al.sub.1.5 In.sub.0.5 W.sub.3 O.sub.12, Al.sub.1.6 In.sub.0.4 W.sub.3 O.sub.12, Al.sub.1.7 In.sub.0.3 W.sub.3 O.sub.12, Al.sub.1.8 In.sub.0.2 W.sub.3 O.sub.12, YAlW.sub.3 O.sub.12, ScAlW.sub.3 O.sub.12, ScGaW.sub.3 O.sub.12, ScInW.sub.3 O.sub.12, ScHoW.sub.3 O.sub.12, ScYbMo.sub.3 O.sub.12 and ErInW.sub.3 O.sub.12. Without limitation, novel compounds satisfying the formula A.sub.2-x.sup.3+ A.sub.y.sup.4+ M.sub.z.sup.3+ M.sub.3-y.sup.6+ P.sub.y O.sub.12 where y=2 may be selected from the group consisting of Hf.sub.2 WP.sub.2 O.

Abstract: According to the method, an aqueous salt solution containing either tin, indium or both, are mixed with an alkali to produce a slurry containing precipitated particles. Then, the slurry is maintained at a predetermined temperature range for a time sufficient to convert the precipitated particles to larger size particles by coagulation or agglomeration. The resulting slurry is then dried and calcined to produce a mixed power. The mixed power is ball milled, press molded and/or cold isostatic press (CIP) molded. The molded body is then sintered to form an ITO sintered body. The ITO sintered body obtained by this process offers superior sinterability whose theoretical density can reach more than 95%.

Abstract: A semiconducting ceramic having negative resistance-temperature characteristics and a critical temperature consisting essentially of a rare-earth transition element oxide which is an oxide of a combination of samarium and nickel, wherein the samarium is partially replaced with Ln which is at least one other element selected from the group consisting of bismuth and rare-earth elements excluding lanthanum and cerium.

Abstract: An oxygen sensor made of alkaline-earth-doped perovskitic lanthanum ferrites with the general formula:La.sub.1-x Me.sub.x FeO.sub.3-.delta.where Me is one of the alkaline earth metals, Mg, Ca, Sr, and Ba and x is the degree of doping, and the oxygen deficit of anion .delta.=0 to 0.25. The degree of doping of the lanthanum ferrites is x=0.1 to 0.3 and resistance is measured in the lanthanum ferrites as a function of oxygen partial pressure.

Abstract: A ceramic composition for absorbing electromagnetic waves and a method for manufacturing the same are disclosed. The composition comprises a raw powder comprising by weight between about 60% and about 80% Fe.sub.2 O.sub.3, between about 3% and about 8% NiO, between about 15% and about 25% ZnO, and between about 3% and about 8% CuO, and a mixture around the raw powder comprising by weight between about 30% and about 50% water, between about 0.2% and about 0.6% a dispersing agent, between about 0.5% and about 1.0% a plasticizer, and between about 0.1% and about 0.4% a lubricant. The method comprises the steps of grinding the powder, converting the grounded powder into granulates, forming the granulates into a shaped body, sintering the shaped body in a furnace, and cooling the sintered body gradually. The ceramic composition can absorb much of the electromagnetic waves generated from electric devices such as cellular phones, beepers, computers, wireless telephones, etc.

Abstract: A real-time, multi-color image ?36! is displayed in a flat screen ?20! composed of a low-phonon, optically transparent, non-pixelated host material doped with active ions. The display uses intersecting infrared laser beams ?22, 24! of different wavelengths to induce a two-frequency upconversion process in the active ions at a point ?28! in the screen. When the ions relax, visible fluorescence is produced. Different points in the display are activated by directing the laser beams ?22, 24! to intersect at different locations within the screen. In one embodiment, beams from two lasers ?28, 30! are controlled by single axis mirrors ?32, 34!. In other embodiments, laser arrays or slab lasers are used to activate points within the screen. Through the use of additional lasers and dopants, multi-color images may be displayed.

Abstract: A certain group of electrically conductive refractory materials presently known for use in high temperature applications as throat constructions, melter sidewalls, forehearth, stacks, port sills, hot face lining for slagging coal gasifiers, slag runners, and linings for nuclear waste encapsulation furnaces may be used as electrodes permitting joule heating at temperatures in excess of 1200 C. in excess of about 4400 hours even in the presence of transition group element(s). More specifically, the invention is an electrode for melting earthen materials, wherein the electrode is made from an electrically conductive refractory material, specifically at least one metal oxide wherein the metal is selected from the group consisting of chrome, ruthenium, rhodium, tin and combinations thereof.

Abstract: An electrochemical process for producing unsaturated hydrocarbon compounds from unsaturated hydrocarbon compounds and for extracting oxygen from a gas containing N.sub.2 O, NO, NO.sub.2, SO.sub.2, or SO.sub.3 is described. The process is characterized by the use of mixed metal oxide materials having a perovskite structure represented by the formula:A.sub.s A'.sub.t B.sub.u B'.sub.v B".sub.w O.sub.xwherein A represents a lanthanide or Y, or a mixture thereof; A' represents an alkaline earth metal or a mixture thereof; B represents Fe; B' represents Cr or Ti, or a mixture thereof; and B" represents Mn, Co, V, Ni, or Cu, or a mixture thereof.

Abstract: The invention is directed to a non-vapor phase process for forming a metal/ceramic composite containing a relatively inert metal such as silver, copper, or nickel by the reaction of a reactive metal or metal alloy containing the inert metal, and a sacrificial ceramic preform. The resulting metal/ceramic composite is essentially the same shape and dimensions as the sacrificial ceramic preform, and exhibits improved physical and mechanical properties, including improved corrosion and wear resistance.

Abstract: A magnetic detecting device is constructed of a substrate, a first magnetic layer formed on the substrate, a first magnetic layer formed on the substrate, an intermediate layer containing an atom indicative of weak spincoupling and formed on the first magnetic film, and a second magnetic layer formed on the intermediate layer. The magnetic detecting device further comprises a unit or supplying a current through the first and second magnetic layers, and a unit for detecting a voltage generated between the first magnetic layer and the second magnetic layer while the current is supplied thereto.

Abstract: New oxide phosphors based on doped gallium oxides, alkaline earth gallates and germanates for electroluminescent display materials. Bright orange red electroluminescence has been obtained in amorphous and crystalline oxides Ga.sub.2 O.sub.3 :Eu for the first time. SrGa.sub.2 O.sub.4 and SrGa.sub.4 O.sub.9 doped with 1-8 mole % of Eu and Tb, CaGa.sub.2 O.sub.4, Ca.sub.3 Ga.sub.2 O.sub.6 and CaGa.sub.4 O.sub.7 doped with 1-4 mole % of Eu, Tb, Pr and Dy, BaGa.sub.2 O.sub.4 doped with 1-2 mole % of Eu and Tb, have been prepared using RF magnetron sputtering onto ceramic dielectric substrates and annealed at 600.degree. C.-950.degree. C. in air or Ar for 1-2 hours. Bright electroluminescent (EL) emission was obtained with wavelengths covering the visible spectrum from 400 to 700 nm, and infrared emission above 700 nm with spectral peaks characteristic of rare earth transitions. The films of CaGa.sub.2 O.sub.4 with 1 mole % Eu achieved 22 fL (75 cd/m.sup.2) at 60 Hz and had a maximum efficiency of 0.

Abstract: The disclosed invention is directed to novel ceramic compositions, and to stabilizer compositions for use with those ceramic compositions. The ceramic materials are formed of rare earth chromium oxides that include a novel combination of stabilizing compounds. Also, dryer or sterilizer devices which incorporate these ceramic compositions for generating infrared radiation for drying or sterilizing various articles.

Abstract: A particle dispersed glassy material includes ultrafine metal particles that are present in a high concentration. The particles are surrounded by a fixation component and, optionally, can be surrounded by a skeleton forming component. The glassy material is produced by firing a substrate having a film thereon that includes a polymer composite having the ultrafine particles uniformly dispersed therein, a fixation reagent and, optionally, a skeleton forming reagent under relatively mild conditions that do not damage the substrate. A method of making the glassy material includes the steps of making a film-forming composition that includes the polymer composite, the fixation reagent and, optionally, the skeleton forming reagent, applying the composition to a substrate, drying the applied composition to produce a film and firing the film to produce the glassy material.

Abstract: Process for preparing a high-T.sub.c superconductor as a precursor material for the oxide-powder-in-tube method (OPIT). The present invention relates to a process for preparing a high-T.sub.c superconductor as a precursor material for the oxide-powder-in-tube method, which involves mixing the oxides of the elements Bi, Sr, Ca and Cu and completely melting them at temperatures of >1000.degree. C., then casting the melt onto a substrate which is kept at room temperature, and disintegrating the cooled melt block and grinding it into a powder.

Abstract: A ceramic composition for absorbing electromagnetic waves and a method for manufacturing the same are disclosed. The composition comprises a raw powder comprising by weight between about 35% to 65% Fe.sub.2 O.sub.3, between about 1% to 5% Al.sub.2 O.sub.3, between about 0.5% to 1.5% Zn, between about 0.5% to 1.0% Cr, between about 3% to 10% Cu, between about 3% to 8% Mn, and between about 1% to 4% Co, and a mixture around the raw powder comprising by weight between 30% to 40% water, between 1.5% to 2.0% a dispersing, and between 1.5% to 2% a plasticizer. The method comprises the steps of grinding the powder, spray drying the grounded powder, forming the sprayed powder into a predetermined shape, calcinating and sintering the shape in a furnace, and cooling the sintered shape gradually. The ceramic composition absorbs the electromagnetic waves generated from electric devices such as cellular phones, beepers, computers, cordless telephones, etc.

Abstract: Thermodynamically stable ceramic composites are provided for use in high temperature reactive environments. A phosphate selected from monazites and xenotimes functions as a weak bond material in the composite. Monazite comprises a family of minerals having the form MPO.sub.4, where M is selected from the larger trivalent rare earth elements of the lanthanide series (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, and Tb) and coupled substituted divalents and tetravalents such as Ca or Sr with Zr or Th. Xenotimes are phosphates similar to monazite where M is selected from Sc, Y, and the smaller trivalent rare earth elements of the lanthanide series (Dy, Ho, Er, Tm, Yb, and Lu).

Abstract: A process for producing ultra-fine barium hexaferrite particles. In the first step of this process, a ceramic precursor material containing barium and trivalent ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.

Abstract: A process for producing ultra-fine yttrium-iron-garnet particles. In the first step of this process, a ceramic precursor material containing yettrium and ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.

Abstract: A sintered ceramic for high-stability thermistors is based on Ni.sub.x Mn.sub.3-x O.sub.4, where x>0. The sintered ceramic has the general formula Cu.sub.z Fe.sub.1-y Ni.sub.x Mn.sub.2-x-z+y O.sub.4, where z=0 to 1.5; y =-0.1 to 0.02; and 1>z>0.5. A method for producing a sintered ceramic for high-stability thermistors includes converting a mixture of starting materials MnO.sub.x, NiO and Fe.sub.2 O.sub.3 into a stable ceramic of an iron-nickel-manganese oxide spinel phase with high thermal stability and aging stability. Another method for producing a sintered ceramic for high-stability thermistors includes calcining a mixture of nickel carbonate, manganese carbonate and .alpha.-iron (III) oxide by heating to over 600.degree. C. in air. After granulometric preparation and compression molding, sintered ceramic bodies are produced by sintering in air or in an oxygen atmosphere.

Abstract: A method for improving the properties of ceramic green bodies is provided. In particular, ceramic green bodies having improved green strength are provided. Incorporating certain acid-containing polymers as binders at a level of at least about 1 to about 15, preferably at least about 3 to about 10 percent by weight based on the weight of ceramic particles improves the green strength of the resulting ceramic green bodies.

Abstract: Enhancement of mechanical properties of ceramic membranes by introduction of a uniformly distributed high-temperature oxidation-resistant metal phase into the brittle ceramic phase to achieve mechanically strong ceramic/metal composites operable in an oxidation atmosphere and at elevated temperatures.