Abstract: A porous ceramic material composed of a sintered porous body of a calcium phosphate compound is described. A multiplicity of capillary void paths having a diameter of 1 to 30 .mu.m and a multiplicity of pores having a diameter of 1 to 600 .mu.m are formed in the sintered porous body. At least part of the pores are connected to the exterior space of the sintered porous body through at least a part of the capillary voids. The porous ceramic material is valuable as a medical material, e.g., a substitute or prosthesis for bone or dental root, and also an electronic material and a genetic engineering material.When the porous ceramic material is embedded in a bone defect of human or animals, osteolytic cells, osteoblasts, erythrocytes and body fluid are selectively allowed to intrude through the porous ceramic material while almost no intrusion of osteoclasts and collagen fibers is allowed.

Abstract: The present invention concerns a method of making a silica-based membrane comprising the steps of:(1) pyrolyzing the material made of one of the class comprising polysilicone rubber, polysilane and polysiloxane at a temperature range of about 500.degree. C. to about 1000.degree. C. for about 2 hours (minimum) in an inert atmosphere; and(2) oxidizing the pyrolyzed material at a sufficient temperature range of about 300.degree. C. to about 1000.degree. C. to crosslink the material with oxygen. The membrane typically has a B.E.T. surface-area measurement of about 220 m.sup.2 /g which indicates a highly porous membrane--about 40 to 70% porosity.

Abstract: A process for the production of shaped articles from silicate material by extrusion and/or pelleting and subsequent annealing is described. In this process, pulverulent layered silicic acids of the general formula H.sub.2 Si.sub.y O.sub.2y+1, in which y is a number from 1.7 to 24, or salts thereof, in which all or some of the H is replaced by at least one cation from the group comprising Li.sup.+, Na.sup.+, K.sup.+, NH.sub.4.sup.+, Ca.sup.2+, Cu.sup.2+, Co.sup.2+, Ni.sup.2+ and Mg.sup.2+, are mixed with water or an organic solvent, the mixture is extruded and/or pelleted to give roll-shaped or tube-shaped pieces and these are then dried and annealed under conditions such that the starting material is chiefly converted into cristobalite and/or tridymite. The same material can also be pressed in a molding tool under pressure. Under these conditions, shaped articles which predominantly consist of cristobalite or tridymite and have a Shore hardness of at least 70 can be obtained.

Abstract: Refractory lining for e.g. casting boxes comprising a refractory matrix and precipitated silica, the silica being precipitated in situ to form a structure, imparting to the material a volume weight of from about 0.8 to about 1.2 g/cm.sup.3, the material being substantially free from carbon, hydrogen and available oxygen; process for the manufacture of such refractory lining.

Abstract: A process for preparing a porous ceramic thin film which comprises applying an anhydrous solution containing an organometallic compound and a multifunctional organic compound to a substrate, and thermally decomposing the compounds. The porous ceramic thin film prepared by the process has pores of not more than 10 .mu.m in pore size, and is useable as for materials of various sensors.

Abstract: The sol-gel process for forming dense, alumina-base ceramics, the process comprising1. preparing a dispersion of aluminum oxide monohydrate containing a precursor of a modifying additive in the form of a soluble salt;2. gelling the dispersion;3. drying the gel dispersion to form a solid;4. calcining the solid; and5. sintering the calcined solid,is improved by adding to the dispersion at least about 10 weight percent, based on the oxide equivalent of the soluble salt precursor, of at least one densification aid selected from the group consisting of alcohols, glycols and polyether compounds having a vaporization point in excess of the temperature at which the dispersion is dried. This improved process is particularly useful for manufacturing abrasive grains.

Abstract: UO.sub.2 particles are brought into contact with liquid water of low pH in an oxidizing environment to dissolve uranyl hydroxide from the particle surfaces and cause more uranyl hydroxide to form and be dissolved. When sufficient uranyl hydroxide has entered the solution, the pH is raised to cause uranyl hydroxide to leave the solution and deposit on the UO.sub.2 particles. The particles are then ready for contact with an appropriate reactant to form a fugitive binder.

Abstract: Cordierite coatings capable of withstanding severe mechanical and thermal conditions. Methods of applying such coatings and components protected thereby.

Abstract: A thermal shock resistant porous sound absorbing body having high durability in which the prior drawbacks of sound absorbing bodies have been obviated, is produced by sintering a mixture comprising 100 parts by volume of ceramic particles having a bulk density of 1.2-2.0 kg/l, a grain size of 0.3-4.0 mm, a thermal expansion coefficient of less than 70.times.10.sup.-7 /.degree. C. and a fire resistant temperature of higher than 1,000.degree. C. and 4-18 parts by volume of an inorganic binder having a melting temperature of lower than that of the ceramic particles and a thermal expansion coefficient of lower than that of the ceramic particles, and further a sizing agent.

Abstract: In the method for manufacturing a non-sintered quartz ware the quartz and clay are comminuted and fully mixed to make a batch of raw materials. The batch is then added with an effective amount of ore coagulant of which the composition comprises 2CaO.SiO.sub.2, 3CaO.SiO.sub.2 and 3CaO.Al.sub.2 O.sub.3, subsequently, the above components are blended with water and then molded into the desired shape by extrusion pressing. The molded product is then dried under slightly higher than the ambient temperature instead of firing which results in less mechanical strength of the conventional fired ceramic ware.

Abstract: The present invention relates to the treatment of gel materials to remove water therefrom.The invention provides a process for removing water from a gel material by contacting the gel material with a gaseous mixture of an organic compound and a gas. The organic compound, the gas and conditions of contacting are selected such that water is extracted from the gel material and passes into the gaseous mixture.The invention in one embodiment may be used to dry gel materials while maintaining an open porous network therein.

Abstract: A silicocalcareous mass with high porosity is obtained by using, in at least partial replacement of the usual silica, ultrafine synthetic silica with a large specific surface of 200 to 500 m.sup.2 per gram to a paste of lime and silica, and possibly adding nonreactive synthetic fibers of organic or inorganic origin. The silicocalcareous mass with high porosity can be used in the field of lining materials for containers intended to store dissolved gases and in the field of insulation materials.

Abstract: A high porosity silicocalcareous mass is obtained by using in at least partial replacement of the usual silica, amorphous ultrafine synthetic silica particles having a specific surface between 150 and 300 m.sup.2 per gram, and a high absorption capacity, and optionally adding nonreactive synthetic fibers of either inorganic or organic origin to the mixture containing the particles. The high-porosity silicocalcareous mass can be used as a lining material for containers, which are intended for storing liquified or dissolved gases and also as an insulation material, such as sound insulation in building construction.

Abstract: A foamed ceramic article is manufactured by adding hexagonally crystalline boron nitride as a foaming agent to a raw material formed preponderantly of a feldspar group mineral and sintering the resultant mixture.

Abstract: An aqueous preparations of a gel-like consistency, containing(a) oils in quantities of from 0.03 to 30% by weight,(b) water-soluble or swellable vinyl polymers in quantities of from 0.2 to 10% by weight,(c) water-soluble or swellable polymers based on natural substances in quantities of from 0.01 to 5% by weight,(d) surfactants in quantities of from 0.01 to 2% by weight and optionally(e) inorganic or organic powders in quantities of from 0.5 to 30% by weight.The aqueous preparation is useful as a porosifying agent in the production of porous ceramic bodies.

Abstract: The invention is concerned with a porous molding obtained by extruding a mixture containing at least one material selected from porous inorganic materials and carbonizable organic materials and at least one binder therefor in the form of threads or strings, accumulating the thready or stringy extrudates to form a mass, and then drying and sintering the accumulated mass. When the at least one material is an organic material, the sintered mass is carbonized in a non-oxidative atmosphere and then activated as usual.

Abstract: An improved process for the preparation of an expanded, water insoluble silicate aggregate. Anhydrous alkali metal silicate is hydrated in the presence of a curing agent, then is subjected to rapid thermal expansion. The process eliminates the use of liquid silicates, and the reaction is conducted in an essentially dry state. The expanded product has extremely low bulk density. When combined with a suitable binder and applied to various substrates, the aggregate functions as an excellent thermal barrier.

Abstract: A method of producing lightweight building blocks, in which an expandable or foamable ceramic material is charged into a mold, compacted and then fired with subsequent cooling.

Abstract: The porosity of heterogeneous type catalysts is increased by incorporating during the preparation a short fibrous type material commonly referred to as a whisker. This type material is highly effective in increasing the volume and diameter of the pores in the catalyst.

Abstract: The present invention resides in an improved ceramic foam filter particulary useful for filtering molten metal. The composition of the ceramic foam material is as follows: 50 to 70% Al.sub.2 O.sub.3 ; 2 to 10% micron sized reactive alumina; 1 to 5% montmorillonite; 1 to 10% ceramic fibers; and from 5 to 25% of a ceramic binder or air setting agent.

Abstract: The disclosed ceramic honeycomb filter comprises a ceramic honeycomb structural body with a multiplicity of parallel channels extending therethrough, selected channels being sealed at one ends thereof by sealing material while the remainder of the channels being sealed at opposite ends thereof by said sealing material in such a manner that, as dust-containing gas flows therethrough from said one ends to said opposite ends, the gas passes through walls between adjacent channels where the dust particles are collected. Said sealing material is alumina cement containing not more than 27% by weight of calcium oxide (CaO), or a mixture of the alumina cement and aggregates.

Abstract: Method and apparatus for measuring gases dissolved in molten metal. Also disclosed are method and apparatus for dissolving gases in molten metal and a method of forming a gas permeable but molten metal impervious ceramic tube. A ceramic member is leached by an invention process so as to be selectively gas permeable. The member is inserted into molten metal to submerge the permeable portion. Then a vacuum is applied to the member and dissolved gases are measured by the change in pressure caused by gases entering from the molten metal. In another embodiment gas is applied to the submerged member to cause it to dissolve in the molten metal.

Abstract: Elastic foamed products or articles having a much better heat resistance than that of the asbestos fiber foamed mass, prepared by drying of an aqueous fiber-dispersed slurry retaining bubbles and consisting essentially of inorganic fibers, synthetic fluormica of the non-restrictive swelling type and surface active agents. In the elastic foamed products, the inorganic fibers having films of the fluormica formed therebetween are evenly entangled with each other, said films having bubbles retained therein.

Abstract: Globular secondary particles of wollastonite group calcium silicate crystals represented by the formulalCaO.mSiO.sub.2.nH.sub.2 Owherein 1.ltoreq.l.ltoreq.6, 1.ltoreq.m.ltoreq.6 and 0.ltoreq.n.ltoreq.1, characterized in that the particles comprise hollow globular secondary particles of the wollastonite group calcium silicate crystals, the globular secondary particles having an average spontaneous sedimentation height of at least 800 ml, an outside diameter of 5 to 110 .mu.m, an average apparent density of 0.04 to 0.09 g/cm.sup.3 and an average shell density defined by the equationY=0.0033X+Bwherein Y is the average shell density, X is the average diameter of the particles, B is a constant, 15 .mu.m.ltoreq.X.ltoreq.40 .mu.m and 0.ltoreq.B.ltoreq.0.115.