Abstract: A refractory product includes CaO component-containing refractory particles and MgO component-containing refractory particles. The refractory material contains, a chemical composition measured after it has undergone heating in a non-oxidizing atmosphere at 1000° C., one or more of the following metal oxides B2O3, TiO2, V2O5, P2O5 and SiO2 in a total amount of 0.1 to 5.0 mass %, and free carbon in an amount of 2 to 35 mass %, with the remainder including CaO and MgO whose mass ratio (CaO/MgO) is in the range of 0.1 to 1.5. In microscopic observation performed at room temperature on the refractory material which has undergone the above heating, an inorganic film comprised of CaO and the one or more metal oxides is formed in at least each CaO surface of the refractory particles each containing either one or both of a CaO component and an MgO component, with a thickness of 0.1 to 25 ?m.

Abstract: The present invention addresses a technical problem of realizing a sprayable refractory material capable of, even when used in a dry-spraying installation process, ensuring mixability between a silica sol and a refractory composition to promote a hardening reaction, thereby achieving excellent durability. Provided is a dry-sprayable unshaped refractory material which comprises a refractory composition, and a silica sol containing a silica solid component in a concentration of 20 mass % to 50 mass %.

Abstract: A mixture of fused grains mainly comprising or composed of an oxide phase of pseudo-brookite type and comprising titanium, aluminum and magnesium, the fused grains having the following chemical composition, in weight percentages on the basis of the oxides: less than 55% of Al2O3; more than 30% and less than 70% of TiO2; more than 1% and less than 15% of MgO, the fused grains also corresponding to the following composition, in molar percentages and on the basis of the single oxides Al2O3, TiO2, MgO: 180?3t+a?220, a?50, m=100?a?t, in which: a is the molar percentage of Al2O3; t is the molar percentage of TiO2; m is the molar percentage of MgO. A ceramic product obtained from such fused grains.

Abstract: The present invention relates to a basic-refractory composition containing magnesium orthotitanate (Mg2TiO4) and calcium titanate (CaTiO3) suitable for use in rotating kilns for the production of Portland cement or lime.

Abstract: A method for manufacturing cordierite ceramics is provided, including forming and heating a cordierite-forming raw material containing ?-alumina. The degree of orientation, expressed by (I006/(I300+I006), where Ihkl is height of X-ray diffraction intensity of an hkl-face of an ?-alumina crystal, by X-ray diffraction measurement of an ?-alumina crystal in a formed article of the raw material for forming cordierite is 0.10 or more.

Abstract: The present disclosure relates to a silica-based crucible material that includes, before sintering or firing, selected amounts of a thermal expansion stabilizer component (B2O3 and Ca2SiO4) which impart improved thermal shock resistance and enhanced ability to withstand repeated thermal cycling, to a sintered or fired crucible made of the material. An illustrative embodiment of the invention provides a crucible material whose chemical composition comprises, in weight %, about 91% to about 98% SiO2, about 1% to about 8% thermal stabilizer component, and up to about 1.0% of additional oxides including MgO, Al2O3 Fe2O3, CaO and ZrO2.

Abstract: The invention concerns a fireproof (refractory) ceramic mix (batch), a fireproof (refractory) ceramic molded body (workpiece) formed of that mix and the use of the molded body.

Abstract: Disclosed are high-porosity cordierite honeycomb substrates having fine pore size, narrow pore size distribution, little or no microcracking, and a high thermal shock resistance. The porous ceramic honeycomb substrates generally include a primary cordierite ceramic phase as defined herein. Also disclosed are methods for making and using the cordierite substrates.

Abstract: Disclosed are a fire-resistant ordinary ceramic batch and a fire-resistant product predominantly comprising a) at least one granular, fire-resistant, mineral, alkaline main component made of an MgO-based or MgO and CaO-based fire-resistant material that is based on at least one alkaline fire-resistant raw material, and b) at least one granular, fire-resistant, mineral, MgO-based, additional elasticator in the form of a forsterite material or a mixture forming forsterite material preferably as small molded articles such as pellets or granulate that is comminuted from compacts. The small molded articles have a grain size ranging from 0.3 to 8 mm while being advantageously provided with a binder at an amount that elasticates the main component.

Abstract: Molten ceramic grains are intended, for example, for applications involving abrading tools, having the following average chemical weight composition, expressed in weight percent based on oxide content: Al2O3: 93% to 97.5%; MgO: 2.2 to 6.5%; SiO2: <0.1%; other impurities: <0.4%.

Abstract: The present invention is directed to a noise suppressor for electronic signals. The noise suppressor at least includes Aluminum Oxide (Al2O3) that is sintered under high temperature, resulting in ceramic Aluminum Oxide (Al2O3) for effectively absorbing or suppressing noise, and reshaping the waveform or filtering waveform glitch of the electronic signals.

Abstract: The invention is directed to a thick film getter composition comprising: (a) desiccant material; dispersed in (b) organic medium comprising (1) curable organic polymeric binder; (2) monomer; and (3) photoinitiator.

Abstract: The composition applied to the refractory structure has a magnesia-based refractory material, calcium carbonate and a binder. After application of the refractory material to a refractory structure and upon application of heat to the applied refractory material a matrix is formed which protects against penetration of the slag into the refractory material. The resulting refractory material has improved hot strength, slag resistance and durability.

Abstract: The invention relates to a refractory ceramic product which comprises: a) ?93% by weight of at least one refractory basic component and b) ?7% by weight of at least one anticorrosive component from the group including: b1) transition metals, b2) compounds of transition metals with each other, b3) non-oxidic compounds of transition metals, b4) oxidic compounds of transition metals, b5) compounds of the transition metals with Ca, Ba, Sr.

Abstract: There is disclosed a ceramic clay obtained by kneading a forming material containing a ceramic forming material, wherein the forming material contains layered double hydroxide, in addition to the ceramic forming material, at a ratio of 0.5 to 50% by mass with respect to a total with the ceramic forming material, and hardness measured by an NGK clay hardness meter is set to 4 to 18 mm. A high-strength honeycomb structure can be obtained capable of preventing or inhibiting pollution and global warming when used in manufacturing a ceramic structure, and having few defects such as cracks.

Abstract: Disclosed is a continuous casting nozzle having a refractory portion formed to contain a dolomite clinker and arranged to define a surface region adapted to be in contact with molten steel, which is capable of protecting a working surface of the nozzle from alumina build-up due to alumina in molten steel, while improving corrosion resistance, even during long-term continuous casting of molten steel. The refractory portion is prepared by adding a binder to a mixed material and subjecting the obtained mixture to kneading, forming and heat treatment. The mixed material comprises a dolomite clinker which has an average particle size of 0.8 mm or less and a CaO content of 50 mass % or less. The mixed material has a ratio W1/W2 of 0.33 or more, wherein W1 is a content by mass of CaO, and W2 is a content by mass of MgO. The mixed material comprises a dolomite clinker and a magnesia clinker. Alternatively, the mixed material comprises a dolomite clinker and a magnesia clinker.

Abstract: The present invention relates to a composition for converting fabric into construction material. The present invention also relates to construction material made from fabric and the process of its manufacture.

Abstract: A fired spinel complex oxide is produced by firing a mixture containing a slag by-produced in chromium refining, a reducer, and a silica-containing material, and is essentially composed of: 29 to 40 percent by weight of Fe2O3; 15 to 20 percent by weight of Al2O3; 9 to 14 percent by weight of MgO; 0 to 4 percent by weight of Na2O; 9 to 17 percent by weight of Cr2O3; 14 to 20 percent by weight of SiO2; and 2 percent by weight or less of CaO. The fired spinel complex oxide shows a Cu—K? X-ray diffraction pattern in which the ratio (b/a) of the diffraction peak intensity of the silica-containing material (b) in the vicinity of 2?=26.7° to the {113} plane diffraction peak intensity (a) in the vicinity of 2?=36° is 0.1 or less.

Abstract: The invention relates to a batch composition for producing a refractory ceramic shaped body, to a shaped body produced therefrom and to the use thereof. The components used are: 68 to 97 wt.-% molten magnesite, sintered magnesite or mixtures thereof, 3 to 20 wt.-% CaO and 0 to 25 wt.-% of a third component.

Abstract: Ceramic mass and thermal transfer media suitable for use in thermal regenerative oxidizers made using a mixture of a ball clay, talc and optionally a dolomitic limestone have enhanced resistance to environments containing halogens and hydrogen halides. The media preferably comprises less than 0.25% by weight of alkali metal, expressed as the oxide, and has a cordierite: silica phase ratio of less than 1.2:1, as determined by X-ray diffraction.

Abstract: Electronically tunable thick film composites of tunable phases such as barium strontium titanate and additional dielectric oxide phases are disclosed. The composite thick films can contain multiple phases such as barium strontium titanate and MgTiO3, Mg2SiO4, CaSiO3, MgO, MgZrO3, CaTiO3, MgAl2O4, and MgSrZrTiO6. The thick films may contain further additives such as zirconnates, stannates, rare earths, niobates and tantalates, for example, CaZrO3, BaZrO3, SrZrO3, BaSnO3, CaSnO3, MgSnO3, Bi2O3/2SnO2, Nd2O3, Pr7O11, Yb2O3, Ho2O3, La2O3, MgNb2O6, SrNb2O6, BaNb2O6, MgTa2O6, BaTa2O6, and Ta2O3 to improve the electronic and microwave properties of the thick film composites. The particle size of these films may be controlled in order to optimize the electronic and microwave properties. The electronically tunable thick film composites may be made by techniques such as screen-printing or spray deposition.

Abstract: Disclosed is a ceramic material which is suitable for coating a body by way of a thermal spraying method and which has a coefficient of longitudinal thermal expansion that may be matched to that of a metal. The ceramic material includes 10 to 95% by weight of MgAl2O4, 5 to 90% by weight of MgO, up to 20% by weight of Al2O3, remainder standard impurities, and has grains of MgO which are embedded in a matrix of MgAl2O4.

Abstract: Ceramic mass transfer media suitable for use in thermal regenerative oxidizers made using a mixture of a clay, talc and optionally a dolomitic limestone have enhanced resistance to environments containing halogens and hydrogen halides.

Abstract: A low-temperature firing ceramic composition contains Sr2MgSi2O7 crystals forming a major crystal phase of the composition. This composition can be produced, for example, by a process including the steps of (a) mixing together a silica powder, a magnesia powder and a strontium oxide powder to obtain a powder mixture; (b) subjecting the powder mixture to a calcination at a temperature of 1,000-1,200° C. to obtain a calcination product containing Sr2MgSi2O7 crystals; (c) mixing the calcination product with alumina powder, boron oxide powder, lithium oxide powder, binder and ethanol to obtain a powder mixture; (d) granulating the powder mixture; (e) shaping the resulting granules into a green body; (f) compacting the green body by a hydrostatic pressing (CIP); and (g) firing the resulting compact in an atmosphere of air, thereby obtaining the composition.

Abstract: The invention relates to free-flowing refractory castable material and castings produced therefrom. Refractory nonbasic and basic refractory castable materials have been known for a long time. The traditional refractory castable materials have thixotropic properties and must be lined sing vibration technology. In the past, free-flowing refractory castable materials were solely based on alumina raw materials. Attempts to produce an aqueous, highly concentrated basic suspension which would Coma the basis of free-flowing refractory castable materials failed to meet the requirements in terms of theological properties and a low degree of to hydration of the MgO-based materials. It is the aim of the invention to provide the above-mentioned refractory castable material for the monolithic lining or repair of high-temperature equipment and for the production of refractory castings. This is achieved by providing a fine-grained and a mixed fine and coarse-grained alternative.

Abstract: A sensor material for measuring physical parameters capable of configuring a sensor capable of directly measuring a high value of physical parameters such as high stress or high pressure without employing a pressure resistance container. The sensor material for measuring static and dynamic physical parameters includes a matrix made of an electrically insulating ceramic material, and piezoresistance materials which are dispersed in the matrix so as to be electrically continuous to each other.

Abstract: A re-usable alumina-magnesia graphite refractory suitably used for a refractory for continuous casting, such as a long nozzle used for pouring a molten metal from a ladle capable of re-use or intermittent use to a tundish, an immersion nozzle used for charging a molten metal from a tundish to a mold and a long stopper for controlling the flow rate of the molten steel; and produced by blending 3 to 60 wt % of magnesia having a particle size of 0.02 to 1.0 mm to a compound comprising mainly alumina and graphite, and kneading, molding, and baking the compound. The raw material compound comprising mainly alumina and graphite can contain spinel or zirconia.

Abstract: The present invention relates to porous calcium zirconate/magnesia composites having a thermally and chemically stable porous structure, which consist of sintered compacts having a fine composite structure stable under high temperatures due to uniformly dispersed equimolar amounts of calcium zirconate [CazrO3] and magnesia [MgO] and controlled grain growth, and a method of producing the same, and the present porous composites are useful as, for instance, a functional material for filtering highly corrosion resistant materials, lightening members used at super-high temperatures, catalyst carriers, insulation or sound-absorbing materials, and the like.

Abstract: The present invention is directed at sintered ceramic articles exhibiting a crystalline phase assemblage comprising, by weight, of 65-95% cordierite and 5-35% of a secondary phase selected from the group consisting of mullite, magnesium-aluminate spinel, and sapphirine and having a bulk analytical composition consisting essentially of about, by weight, 32-51% SiO2, 35-49% Al2O3, 7-16% MgO. Furthermore, the ceramic articles exhibit an effective strength of greater than about 3000, a CTE of less than about 15×10−7/° C., over the temperature range of 25° C., to 1000° C., and a total intrusion porosity, as measured by a Hg intrusion method, of at least 20%. This invention also relates to a method for producing a sintered ceramic article having the aforementioned cordierite and secondary minor phase mixture.

Abstract: A graphite-containing monolithic refractory material comprises at least one component selected from alumina and alumina-magnesia spinel, which are divided into selected particle size regions, artificial graphite having a selected average particle size, and pitch powder. The refractory material may optionally comprise a selected amount of silicon carbide having a selected average particle size. The graphite-containing monolithic refractory material exhibits excellent casting workability at a low moisture content, and both excellent corrosion resistance and spalling resistance. The refractory material is suitable as a casting monolithic refractory material for lining a topedo ladle car.

Abstract: The invention relates to a porous ceramic used for producing alkali ion water. The ceramic of the invention includes finely particulate zeolite having an average particle size of 0.1 to 40 &mgr;m and an alkali ion producing material as components. Besides the above components, the invention preferably comprises a fibrous mineral and/or a clay mineral. To produce the ceramic of the invention, a slurry obtained by grinding zeolite by a wet process, a slurry obtained by grinding the alkali ion producing material and the clay mineral by a wet process and a slurry obtained by grinding the fibrous mineral are first mixed and stirred to prepare a mixed slurry. This mixed slurry is then dried and fired to obtain a sintered body.

Abstract: There is provided a jig for use in firing of ferrite-made member (e.g. deflection yoke). The jig contains MgO.Al.sub.2 O.sub.3 spinnel as the main component. In the jig, the molar ratio of total MgO and total Al.sub.2 O.sub.3 is 25:75 to 75:25; and RO, which is at least one kind of oxide selected from the group consisting of ZnO, CuO, MnO, NiO, CaO, SrO, BaO, PbO and CdO, is contained in an amount of 0 to 25 mole % per 100 mole % of the sum of total MgO and total Al.sub.2 O.sub.3. This jig is unreactive to a material (e.g. deflection yoke) to be fired and consequently gives rise to no dimensional change of the material to be fired.

Abstract: This invention is directed to ceramic metal composite useful as a refractory and having improved abrasion, corrosion, and oxidation resistance. The ceramic metal composite of the present invention is comprised of ceramic refractory aggregate, metal particulate, and a nonaqueous binder wherein the ceramic refractory aggregate, metal particulate, and binder residuals react to form a three-dimensional ceramic-metal matrix. The ceramic-metal matrix is further stabilized by bonds between the metal particulate, reaction products of the metal particulate, and the ceramic refractory aggregate.

Abstract: The present invention relates to a protection tube for protecting heaters and sensors used in melting furnace for reprocessing of incinerator ash, other melting furnace, and various other furnaces, the protection tube being excellent in resistance to heat and resistance to corrosion so as to be usable favorably for a long period. The heat- and corrosion-resisting protection tube is formed in a tubular body closed at an end, being composed of ceramics, and the ceramics have a softening point over 1700.degree. C. in the air atmosphere, a three-point bending strength of 150 MPa or more at 1450.degree. C., a resistance to heat shock of .DELTA.T of 150.degree. C. or more by water quenching method, and a mean grain size of 2 .mu.m or more, having a composition of 50 mol % or more of Al.sub.2 O.sub.3 and 50 mol % or less of MgO.

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: A microporous insulation material contains an ingredient which exhibits a phase transition and functions to maintain temperatures attained by an object shielded by the microporous insulation material, during exposure of the microporous insulation material to a high temperature environment, at an acceptable level over a given period of time. The insulation material is especially suitable for insulating flight data and voice recorder systems. The microporous insulation material contains inorganic particulate material; endothermic compounds, (optionally) an opacifier, inorganic fiber and preferably, a dry resin or other binder. The inorganic particulate material can comprise only hydrophilic material or both hydrophilic and hydrophobic material.

Abstract: Herein disclosed is a filter medium for molten metals which consists of a sintered body of a mixture comprising 100 parts by weight of at least one refractory grain selected from the group consisting of alumina particles and Al.sub.2 O.sub.3.MgO spinel crystal particles; and 5 to 25 parts by weight of an inorganic binder which comprises 60 to 90% by weight of Al.sub.2 O.sub.3.MgO spinel crystal powder, 5 to 12% by weight of B.sub.2 O.sub.3, and not more than 30% by weight of at least one oxide selected from the group consisting of Al.sub.2 O.sub.3, MgO and TiO.sub.2. The filter medium is used for filtering off solid impurities mixed in molten metals, in particular, molten aluminums.

Abstract: This invention relates to cement-free refractories exhibiting high green strength, improved corrosion resistance, and improved magnesium oxide hydration resistance useful as refractory castables for steel ladles, slag contact areas, ladle sidewalls and bottoms, and the like and as precast refractory shapes, such as well blocks, nest blocks, and the like. More particularly, this invention is directed hydraulically-bonded monolithic refractories containing a calcium oxide-free binder comprised of a hydratable alumina source and magnesium oxide and which exhibit high green strength, improved corrosion resistance, improved magnesium oxide hydration resistance, and controllable work and set times.

Abstract: A powdered mixture of chemicals for forming a refractory composition, including a filler consisting of refractory particles, metal particles and metal peroxide containing particles, wherein the metal peroxide containing particles have a calcium peroxide content of at most 75 wt %, a magnesium peroxide content of at most 30 wt %, a barium peroxide content of at most 92 wt %, and/or a strontium peroxide content of at most 90 wt %. A refractory composition prepared from said mixture, a method for forming said composition and a method for using same are also disclosed.

Abstract: The present invention relates to multi-purpose mineral powder emitting the large quantities of far infrared rays, negative ion and oxygen heat having ingredients of germanium of 20 weight percent, clinochlore of 10 weight percent, jade of 10 weight percent, zeolite of 10 weight percent and halite of 50 weight percent, and its process, in which the above five ingredients are pulverized to about 300 mesh; are placed into an inner surface having silver leaf (Ag) of an internal furnace made of chondrodite; are heated through a heating plate for nine days at about 1000.degree. C. so as to have thermal deformation after placing chondrodite pulverized to about 200 mesh between the inner surface of the electric heating plate and the outer surface of the internal furnace; and are then pulverized to about 325 mesh.

Abstract: The present invention relates to a refractory binder that comprises a mixture of aqueous phosphate and silica sol. The silica sol has been found to gel and set in a surprisingly effective and useful way. Preferably, the refractory binder further incorporates a small amount of magnesia as an accelerator. The present invention also provides a method of binding a refractory material such, for example, as alumina, zirconia mullite or aluminium silicate by using a refractory binder according to the invention.

Abstract: A ceramic and method of producing the same are disclosed, the ceramic having as principal ingredients natural zeolite and shells, wherein silver nitrate, magnesium oxide, potassium oxide, sodium oxide selenium oxide and ferric oxide are added thereto, and the resultant mixture fired to produce a granular ceramic. The granular ceramic enables the production of deoxidized water having an appropriately low oxidation reduction potential, for use as drinking water and the like.

Abstract: A thin film composite material comprises barium strontium titanate represented as Ba.sub.1-x Sr.sub.x TiO.sub.3 wherein x is greater than 0.0 but less than or equal to 0.75 and a magnesia-based compound such as MgZrO.sub.3, MgTiO.sub.3, MgAl.sub.2 O.sub.4 and mixtures thereof. The thin film ferroelectric composite is made using pulsed laser deposition and exhibits high tunability, low loss and a low dielectric constant.

Abstract: A microporous insulation material contains an ingredient which exhibits a phase transition and functions to maintain temperatures attained by an object shielded by the microporous insulation material, during exposure of the microporous insulation material to a high temperature environment, at an acceptable level over a given period of time. The insulation material is especially suitable for insulating flight data and voice recorder systems. The microporous insulation material contains inorganic particulate material; endothermic compounds, an opacifier, inorganic fiber and preferably, a dry resin binder. The inorganic particulate material can comprise only hydrophilic material or both hydrophilic and hydrophobic material.

Abstract: A pulverulent fiber-reinforced spray mix is disclosed in which about 0.02 to 0.3 wt. % of flexible, thermoset polymer fibers resistant to decomposition at a temperature up to about 400.degree. F. are added for each 100 wt. % of other solids in the mix to form a mix which both avoids formation of mat-like structures in the dry hopper of refractory spray apparatus and provides a sprayed lining that is resistant to cracking and peeling during dry-out and preheat. The invention also comprises sprayable compositions formed by admixing water with the mix.

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 castable refractory which comprises a matrix, making up 100 wt % in total, composed of 3-20 wt % of magnesia clinker having a particle diameter smaller than 0.21 mm and containing more than 95 wt % of MgO and 0.5-3.0 wt % of alumina cement in terms of CaO, with the remainder being alumina, and 0.1-3 wt % of ultrafine powder of amorphous silica and 3-9 wt % of alumina coarse grains having a particle diameter of 8-20 mm, both in terms of outer percentage of the amount of the matrix.

Abstract: A castable refractory which comprises a matrix, making up 100 wt % in total, composed of 3-20 wt % of magnesia clinker having a particle diameter smaller than 0.21 mm and containing more than 95 wt % of MgO and 0.5-3.0 wt % of alumina cement in terms of CaO, with the remainder being alumina, and 0.1-3 wt % of ultrafine powder of amorphous silica and 41-100 wt % of alumina coarse grains having a particle diameter of 10-50 mm, both in terms of outer percentage of the amount of the matrix.

Abstract: Ceramic ferroelectric composite material-BSTO-Magnesia based compounds hag a low dielectric constant, low loss tangent and high tunability are disclosed. The composite material comprises Barium Strontium Titanate (BSTO) and a magnesia compound selected from the group consisting, MgZrO.sub.3, MgAl.sub.2 O.sub.4, and MgTiO.sub.3. The preferred composite is represented by Ba.sub.1-x Sr.sub.x TiO.sub.3 -magnesia compound, wherein x is greater than 0.00, but less than or equal to 0.75, and wherein the percent weight ratio between BSTO and magnesia compound ranges from approximately 99%-40% and 1%-60%, respectively. The novel materials possess superior electronic properties, and they may be employed in various antenna systems.

Abstract: The present invention pertains to the use of a refractory ceramic brick based on MgO containing 3% to 23% of a pre-synthesized MgO.times.Al.sub.2 O.sub.3 (MA spinel) with an Al.sub.2 O.sub.3 content of 75 to 95 wt. % for lining cement rotary kilns.