Abstract: The photocatalytic granular mixture for mortar and concrete includes a photocatalyst in the form of at least two granular classes with different B.E.T. specific surfaces. It has a photocatalytic activity greater than that of a monodisperse photocatalyst with a single range of B.E.T. specific surface, and thus permits, in association with a conventional hydraulic binder, to obtain construction and repair materials whose aptitude for self cleaning, for the reduction of odors, and for the depollution of ambient air, is considerably improved.

Abstract: Methods for cementing and cement compositions are provided, wherein the cement composition comprises cementitious material and an aqueous suspension of zeolite and a chromate reducing agent.

Abstract: Cement compositions are provided that comprise a hydraulic cement, water, and a set retarder composition, the set retarder composition comprising an acrylamide polymer derivative; and an iron compound. In some embodiments, cement compositions are provided that comprise a hydraulic cement comprising a cement, water, and a set retarder composition, the set retarder composition comprising a lignin-based retarder and an iron compound.

Abstract: A fiber reinforced cementitious material and the fiber used therein are disclosed. The fiber reinforced cementitious material includes a conventional cementitious material and less than 5 pounds per cubic yard of the cementitious material of fibers dispersed therein. The fibers are made of a mixture of a thermoplastic polymer and an organometal compound wherein the metal of the compound is selected from the group consisting of Ti, Si, Zr, Al, and combinations thereof, and the organometal compound comprising less than 10% by weight of said fibers.

Abstract: A chromium VI reducing composition comprising particles of solid material selected from the group consisting of iron (II) sulfate and tin sulfate, the particles being substantially uniformly dispersed within a liquid carrier. Methods for modifying hydratable cementitious materials using the chromium reducing composition are also disclosed and provide advantages over dry powder or dissolved forms of sulfate compositions when used in cement manufacturing.

Abstract: A magnetic device and method for making it involve a magnetic device specifically constructed of grains in a matrix. The matrix may be cement or plaster. The grains have an average diameter that is greater than their magnetic domains. The device may be applied to shielding applications for frequencies ranging from 100 kHz to 10 GHz. The shielding may be applied to walls of a building, consumer products such as magnetic disks, and the like. The grains may be any ferromagnetic material, including ferrite.

Abstract: A hydraulic binder includes cement as main ingredient, and a mixture added to the cement and made of moist green vitriol and a drying agent selected from the group consisting of dry sand with a granulation between 0.1 mm and 0.4 mm, catalytic dust, silica gel and alumina.

Abstract: A fiber reinforced cementitious material and the fiber used therein are disclosed. The fiber reinforced cementitious material includes a conventional cementitious material and less than 5 pounds per cubic yard of the cementitious material of fibers dispersed therein. The fibers are made of a mixture of a thermoplastic polymer and an organometal compound wherein the metal of the compound is selected from the group consisting of Ti, Si, Zr, Al, and combinations thereof, and the organometal compound comprising less than 10% by weight of said fibers.

Abstract: A method is disclosed for constructing, verifying, and maintaining underground vaults that isolate and contain radioactive burial sites. The method employs a buoyant lift technique to isolate a block of soil containing the contaminates from the surrounding soil. An impermeable synthetic liner is embedded in the vault to enhance the integrity of the system. The integrity of the vault is monitored by a system of sensors placed both inside and outside of the sealed vault. The method eliminates the need to excavate or drill in the contaminated areas.

Abstract: A colored cement composition and method for preparing colored cement for use as mortars, grouts, stuccos or pool plasters that uses a colored cement produced from clinkers formed with pigment prior to sintering and a naturally occurring colored or pigmented inert filler.

Abstract: A settable composition suitable for coating surfaces; e.g., walls of a mine comprises (i) a cementitious composition comprising the following components: (a) at least 25% preferably at least 40% of a reactive cement having a C to A or (A+X) ratio of greater than 1:1 preferably greater than 1.2:1, where X is S* or S or F (b) from 0 to 10% of lime and (c) from 5 to 70% preferably 10 to 40% of calcium sulphate, and where the sum of (b) and (c) is at least 15% the % being by weight based on the combined weight of (a), (b) and (c) and where the proportions of the components are such that the composition on hydration is capable of absorbing at least its own weight of water and (ii) an aqueous emulsion of an organic polymer, the amount of (ii) in relation to (i) being such as to provide a weight ratio of polymer solids to combined weight of (a), (b) and (c) of from 0.5:1 to 10:1, preferably 0.

Abstract: The invention provides an antibacterial agent for concrete comprising a silver compound, a copper compound and an ion-retaining compound; a concrete composition comprising the antibacterial agent; and a concrete product produced from the concrete composition. The concrete composition containing the antibacterial agent and the concrete product produced using the concrete composition show excellent antibacterial effect against causative bacteria of the corrosion of concrete such as sulfur reducing bacteria, sulfur oxidizing bacteria and carboxylic acid-producing bacteria, in particular, in sewage treatment plants.

Abstract: The invention provides an antibacterial agent for concrete comprising a silver compound, a copper compound and an ion-retaining compound; a concrete composition comprising the antibacterial agent; and a concrete product produced from the concrete composition.

Abstract: A hydraulic binder, includes cement, and a mixture added to the cement and made of moist green vitriol and an inert carrier substance in the form of silica gel or alumina.

Abstract: A composition and method for preparing colored cement for use as mortars, grouts, stuccos or pool plasters that employs a pigmented inert filler.

Abstract: A conductive paste for defogging heat wires of automobile windows contains a silver powder having particle size in the range of about 0.1 to 20 &mgr;m, a molybdenum compound such as molybdenum silicide or molybdenum boride, a glass frit having a softening point of 730° C. or less and an organic vehicle. The conductive paste can uniformly darken the conductive heat wire regions of the automobile window without producing any harmful substances. Also, it can ensure sufficient bonding strength of lead wires.

Abstract: The invention provides cementitious dry mortars comprising a) from 0.5 to 80% by weight of cement, b) from 0 to 97% by weight of fillers, c) from 0 to 3.5% by weight of thickeners, wherein a polymer powder composition is present, with d) from 1.0 to 80% by weight of redispersible polymer powder, e) from 0.02 to 4.0% by weight of one or more compounds from the group consisting of zinc oxide, zinc hydroxide, and zinc hydroxide carbonate, f) from 0 to 30% by weight of alkali metal hydroxide and/or alkaline earth metal hydroxide, based in each case on the overall weight of the dry mortar, the percentages by weight adding up to 100% by weight.

Abstract: The invention relates to a cement slurry for cementing an oil well or the like, the slurry having a density lying in the range 0.9 g/cm3 to 1.3 g/cm3, and being constituted by a solid fraction and a liquid fraction, having porosity (volume ratio of liquid fraction over solid fraction) lying in the range 38% to 50%. The solid fraction is constitued by a mixture of lightweight particles, microcement and optionally portland cement and gypsum. Such cements have remarkable mechanical properties due to their very low porosity in spite of having very low density.

Abstract: The invention provides a hydraulic binder, dry premixes and cement compositions having the improved property of maintaining unaltered, brilliance and coloring quantity for a longer time period. These compositions contain, in bulk, particles of a photocatalyst capable of oxidizing polluting substances in the environment in the presence of light, oxygen and water.

Abstract: Described herein is the use of a combination of organic additives that is particularly advantageous for the preparation of cementitious compositions having a high conservation of the degree of white, which contain in mass a photocatalyst that is able to oxidize, in the presence of light, air and ambient humidity, pollutant substances present in the environment, the said photocatalyst being, in particular, titanium dioxide prevalently in the form of anatase. The above combination of additives comprises the following: a melamine resin; a cellulose ether; a polymer chosen from among an ethylene polymer, an acrylic polymer, and a terpolymer comprising as co-monomers at least one ester of acrylic acid with an alcohol and at least one ester of vinyl alcohol with a carboxylic acid, or alternatively, an acrylic, styrene or butadiene latex; and a chemically modified starch.

Abstract: Amorphous ferrophosphorus alloys (Formula II) are useful as shrinkage control agents in cement composites, and new amorphous ferrophosphorus alloys particularly useful for this purpose are disclosed having the formula: FeaCrbMcPdCeSif  (Formula I) wherein M is a metal selected from the group consisting of Vg, Nih, Mni and mixtures thereof, and a is about 66-76, b is about 1-10, c is about 2-7, d about 12-20, e about 1-6, f is less than about 2, g is about 1-5, h is less than about 2 and i is less than about 2, atomic percent.

Abstract: This invention provides a resin composition which is cured by active radiation rays, shows less absorption in the visible light region, has solar radiation blocking ability and is excellent in scratch resistance, and a film coated with the resin composition. Said resin composition comprises solar radiation absorbable fine particles of a metal oxide such as zinc antimonate anhydride, tin oxide, ATO (antimony doped tin oxide), ITO (tin doped indium oxide) or the like and an active radiation ray polymerizable (meth)acrylate having a (meth)acryloyl group, and a coating obtained therefrom has excellent paint film hardness and scratch resistance.

Abstract: A method for forming a radiation-absorbing barrier around a radioactive component by flowing a radiation-absorbing cement grout into a container which encloses the component. The radiation-absorbing cement grout comprises a cement slurry, a finished foam material, a bentonite gel, and a radiation-absorbing metal constituent.

Abstract: Production of an anti-microbial effect in an alcohol or water based electrolyte is achieved by preparing silver materials that form complex ions other than Ag.sup.+, Ag.sup.2+, or Ag.sup.3+, and which produce an anti-microbial effect that is greater than that produced by an equivalent amount of silver as Ag.sup.+. Exemplary complex silver ions produced include Ag(CN).sub.2.sup.-, AgCN(.sub.aq)(ion pair), Ag(NH.sub.3).sub.2.sup.+, AgCl.sub.2.sup.-, Ag(OH).sub.2.sup.-, Ag.sub.2 (OH).sub.3.sup.-, Ag.sub.3 (OH).sub.4.sup.-, and Ag(S.sub.2 O.sub.3).sub.2.sup.3-. The silver materials may be prepared as powders or as solutions or suspensions containing the complex silver ions. The silver materials might also be prepared as coatings, foils, powders, or fine grain or nanocrystalline powders, which are formed with atomic disorder to provide sustained release of the complex silver ions.

Abstract: A method for coloring cementitious systems using compacted inorganic granules, wherein said compacted inorganic granules comprise an inorganic pigment and a dispersing agent. Particularly, a method for coloring cementitious systems using compacted inorganic granules; wherein said compacted inorganic granules are produced by a process consisting of: (a) mixing an inorganic pigment and a dispersing agent, (b) compacting the mixture, (c) milling the compacted mixture, and (d) classifying the compacted mixture into at least one oversize material stream, at least one undersize material stream and at least one product stream of compacted inorganic granules; and wherein the coloring effect of the compacted inorganic granules in the cementitious system equals or exceeds the powder standard.

Abstract: A Portland cement clinker free of C.sub.4 A.sub.3 S having the following proportions of clinker phases, in % by wt.:--C.sub.3 S: 40 to 80--C.sub.4 AF: <20--C.sub.2 S: <30--C.sub.3 A: <20and a SO.sub.3 content from 1.0 to 3.0% by wt., based on the clinker, obtained by burning a mixture of raw materials containing CaO, SiO.sub.2, Al.sub.2 O.sub.3, Fe.sub.2 O.sub.3 and an additive containing SO.sub.3 at temperatures from 1200.degree. to 1350.degree. C. centigrade, the use thereof and a Portland cement.

Abstract: A method for forming a radiation-absorbing barrier around a radioactive component by flowing a radiation-absorbing cement grout into a container which encloses the component. The radiation-absorbing cement grout comprises a cement slurry, a finished foam material, a bentonite gel, and a radiation-absorbing metal constituent.

Abstract: Anti-microbial coatings and method of forming same on medical devices are provided. The coatings are formed by depositing a biocompatible metal by vapor deposition techniques to produce atomic disorder in the coating such that a sustained release of metal ions sufficient to produce an anti-microbial effect is achieved. Preferred deposition conditions to achieve atomic disorder include a lower than normal substrate temperature, and one or more of a higher than normal working gas pressure and a lower than normal angle of incidence of coating flux. Anti-microbial powders formed by mechanical working to produce atomic disorder are also provided. The invention extends to other metal coatings and powders similarly formed so as to provide enhanced solubility.

Abstract: A method of recovering steel plant waste revert materials including blast furnace flue dust and sludges involves mixing the revert materials with water to provide a total moisture content of about 14-20% by weight, then adding Portland cement as a sole binder, mixing, and, when the water content is limited to about 18 to 20%, casting the mixture onto the ground in the form of a slab or, when the water content is limited to about 14 to 16% and an accelerator for curing the cement is used, casting the mixture onto a conveyor in the form of preformed streams, curing the cast mixture and breaking it up to provide 1/2 inch to 5 inch agglomerate particles that can be recycled to the blast furnace.

Abstract: A Low Heat High Performance Concrete (LHHPC) composition having a very low cement content and high W/CM ratio offers high strengths, low heat of hydration, excellent volumetric stability, low chloride permeability and low pH. To reduce the cement content while maintaining high performance, silica fume and silica flour are used in large quantities. The LHHPC composition can be used for high mass concrete structures and other applications which require low heats of hydration yet offers compressive strength comparable to Standard High Performance Cement (SHPC).

Abstract: An article of manufacture and method of manufacture of a cement product composition. A cementitious clinker consisting essentially of an alpha belite and a ferrite phase having a composition of about 0.04-0.13 moles Na.sub.2 O, 0.03-0.07 moles K.sub.2 O, 0.09-0.18 moles Fe.sub.2 O.sub.3, and 2.8 moles dicalcium silicate.

Abstract: A toxic waste fixant for detoxification of a contaminated soil, sediment, and or sludge material includes a mixture of: ferric and/or ferrous sulfate, manganese sulfate, and/or aluminium sulfate and/or Portland cement, and/or gypsum (calcium sulfate), and/or blast furnace slag, and/or lime (calcium oxide). Fixants made from mixtures of the above compounds are designed to prevent leaching in excess of regulatory standards for specified inorganic and organic toxic compounds and elements. These fixants will also reduce the concentration of most organic toxic compounds through various chemical reactions and bonding as determined by solvent extractions and analysis by GC/MS. The ferric and/or ferrous sulfate may be partially or completely replaced by cobalt sulfate, whereas instead of the respective sulfates the corresponding chlorides may be used as well.

Abstract: A cementitious composition which contains a base which preferably has a solubility which is greater than that-of calcium hydroxide. The amount of this base is such as to provide 0.1 to 2% by-weight of hydroxide relative to the weight of the cementitious composition. The cementitious composition may be a polymer modified mortar which is used as the anode overlay in a cathodically protected reinforced concrete.

Abstract: There is provided a method for the ecologically safe disposal of lead-contaminated hazardous industrial wastes (such, as for example, those generated as discardable by-products in primary and secondary lead smelting operations, especially, blast furnace slags and matte), which comprises reducing the size of the lead-contaminated industrial wastes and treating them, prior to encapsulation in a hardenable material, with the naturally occurring zeolite, clinoptilolite, in an amount sufficient to prevent lead ions (Pb.sup.+2) from leaching out of the industrial wastes, through exposure to the action of atmospheric agents (e.g., hot air and rain, or as a result of cyclical freezing and thawing in temperature climates), even over an extended period of time.

Abstract: Chromite by-products having a composition which includes FeCr.sub.2 O.sub.4 as well as iron, aluminum, magnesium, sodium, calcium and silicon oxides are directly mixed with cement mortar and with the aggregates on use, or added to the water, producing the effect of corrosion inhibition of the steel reinforcements.

Abstract: The present invention relates to the use of manganomanganic oxide particles containing at least 90% by weight of manganomanganic oxide, said particles having a density of 4.50 to 4.75 g/cm.sup.3 and a particle size of at least 98% below 10 .mu.m, as a weight material for drilling mud fluids and for cement slurries for cementing oil wells.The manganomanganic oxide particles which are used are preferably recovered from off-gases which evolves during refining of ferro-manganese melts.

Abstract: A refractory composition is disclosed which possesses low porosity, high density, exceptional strength and high abrasion resistance and is useful for lining fluid catalytic converter units, e.g., catalyst transfer lines, riser lines, J-bends, cyclones and all other areas where hot abrasion resistance and low thermal conductivity are desired. The composition consists essentially of by weight: (a) 44 to 89% of an abrasion-resistant refractory grain; (b) 10 to 50% of a hydraulically setting cement; (c) 1 to 6% of a filler consisting of very fine, substantially spherical particles of a metal oxide selected from the group consisting of Al.sub.2 O.sub.3, Cr.sub.2 O.sub.3, ZrO.sub.2, TiO.sub.2, clay minerals, carbon and fume SiO.sub.2 ; and (d) 0.01 to 1%, based on the total weight of the constituents (a), (b) and (c), of additives selected from deflocculants and wetting agents.

Abstract: A semiconducting internal boundary layer ceramic composition having a fine grain structure suitable for use in thin-layer multilayer capacitors is made in one step by firing a mixture comprising a major amount of finely divided strontium titanate, a minor amount of a compound containing either strontium or titanium, or an element functionally equivalent thereto, a minor amount of a semiconductor forming ingredient (dopant), the identity of which depends on whether the mixture is rich in strontium or in titanium, and a minor amount of a counterdopant selected from cuprous oxide or silver oxide. When the mixture is rich in titanium, the chemical doping agent used to produce semiconductivity is an oxide of a trivalent metal selected from bismuth, boron, iron, antimony, lanthanum and the rare earth and transition metals. When the mixture is rich in strontium, the dopant is an oxide of a pentavalent or hexavalent metal selected from tungsten (+6), niobium (+5), tantalum (+5), and molybdenum (+6).

Abstract: Monolithic capacitors having Q's of 3500 include copper electrodes buried in a non-reducible body that consists of a crystalline magnesium titanate phase and an intergranular glass phase. The crystalline phase contains magnesium meta-titanate and/or ortho-titanate. Magnesium di-titanate is excluded from the body as are the oxides of lead, bismuth and cadmium, which materials are reducible at the firing conditions necessary to preserve the integrity of the copper electrodes.

Abstract: A particulate mixture of an alkali metal hydroxide solvent, a reactant selected from the group consisting of titanium oxide, zirconium oxide and mixtures thereof, and an alkaline earth reactant selected from the group consisting of barium oxide, strontium oxide, and mixtures thereof, is heated to melt the alkali metal hydroxide solvent in which the reactants dissolve and react precipitating a titanate, zirconate or solid solutions thereof.

Abstract: An improved polycrystalline semiconducting ceramic composition can be produced from a novel powder which comprises a reduced alkaline earth metal titanate doped with a hexavalent metal oxide such as (MO.sub.3) (Bi.sub.2 O.sub.3).sub.x where M is tungsten or molybdenum, and x ranges from 0 to 7. This powder, which has a mean particle size on the order of less than 10 microns, may be liquid phase sintered with lead germanate to produce a ceramic composition having an extremely fine grain size. By reducing the earth metal titanate (either chemically or gaseously) prior to the liquid phase sintering with lead germanate, particle or grain size growth is substantially eliminated, and the grain size of the ceramic composition is similar to the original particle size of the earth metal titanate.

Abstract: Addition of from about 0.1 to about 6.0% by weight of V.sub.2 O.sub.5 to (PZT)lead zirconate-lead titanate powder promotes rapid densification at temperatures below 1000.degree. C. and eliminates the need for PbO atmosphere control. Densification to greater than 98% of theoretical density is achieved with firing times as short as 1-5 minutes. Dielectric properties depend upon the amount of V.sub.2 O.sub.5 added and upon the microstructure developed, but in general are equivalent to those reported for conventional PZT compositions.

Abstract: Submicron titanium diboride powder and other hard, refractory metal boride powders, such as zirconium diboride and hafnium diboride powders, are prepared by vapor phase reaction of the corresponding metal halide, e.g., titanium halide, and boron source reactants in the presence of hydrogen in a reaction zone and in the substantial absence of oxygen, either combined or elemental. In a preferred embodiment, the metal halide, e.g., titanium tetrachloride, and boron source, e.g., boron trichloride, reactants are mixed with a hot stream of hydrogen produced by heating hydrogen in a plasma heater. The reaction zone is maintained at metal boride forming temperatures and submicron solid metal boride powder is removed promptly from the reactor and permitted to cool. The preponderant number of metal boride particles comprising the powder product have a particle size in the range of between 0.05 and 0.7 microns.

Abstract: A method of making articles of Group IVb metal diboride powder by cold pressing and sintering is disclosed. Group IVb metal diboride powder is pressed in a mold substantially below sintering temperatures to form a cold pressed green piece having substantially uniform compaction over its major surfaces. The piece is enclosed but not confined in a thermally conductive receptacle which has been pre-fired to remove volatile impurities, and the enclosed piece sintered without the simultaneous application of pressure. The powder and green piece are maintained under inert atmosphere before and during sintering. The method is particularly useful for the production of flat plates, where warpage during sintering may otherwise be a problem.

Abstract: Cold formed and sintered titanium diboride shapes of high density are prepared by grinding particulate carbothermic titanium diboride in a mill having non-contaminating grinding media in the presence of an inert, substantially oxygen-free liquid grinding aid to form finely-divided titanium diboride powder having a surface area of at least about 3 square meters per gram, cold forming the finely-divided titanium diboride powder into a desired shape and sintering the shape to produce a titanium diboride article having a density of at least 95 percent of the theoretical density of titanium diboride.

Abstract: A basic ceramic composition of high dielectric constant type ceramic composition comprises from 68.67 to 69.19% of PbO, from 3.67 to 4.09% of MgO, from 24.17 to 26.99% of Nb.sub.2 O.sub.5 and from 0.25 to 2.97% of TiO.sub.2, all percentages being by weight. Modified composition may comprise additive of Pb(Mn.sub.2/3 W.sub.1/3)O.sub.3, Pb(Mn.sub.1/3 Nb.sub.2/3)O.sub.3, Pb(Mn.sub.1/3 Ta.sub.2/3)O.sub.3, Pb(Mn.sub.1/2 W.sub.1/2)O.sub.3, MnO, and MgO. Modified composition may comprise Ba, Sr and Ca, which replace Pb of the basic ceramic composition. In a modified composition, the content of B site elements may be larger than that of A site element of an ABO.sub.3 crystal of the high dielectric constant type ceramic composition. A high dielectric constant, low dielectric loss, low temperature dependence of capacitance, high insulation resistance and a low sintering temperature are provided by the ceramic compositions of the present invention.

Abstract: A novel high strength, high heat resistance sintered body suitable for use as refractory and abrasive materials is proposed. The sintered body comprises from 99.99 to 70% by weight of a combination of at least two kinds of metal diborides selected from the group consisting of diborides of Ti, Ta, Cr, Mn, Mo, Y, V, Hf, Nb, Al and Zr and from 0.01 to 30% by weight of a metal boride or borides selected from the group consisting of borides of nickel, iron and cobalt.The sintered body of the invention can be prepared by sintering the powdery mixture of the components at a relatively low temperature of 1800.degree. C. or lower and has a bending strength as high as 190 kg/mm.sup.2 and a Vickers hardness of 3300 kg/mm.sup.2 at room temperature and 2400 kg/mm.sup.2 at 1000.degree. C.

Abstract: A method for producing piezoelectric ceramics of a Pb(Sn.sub..alpha. Sb.sub.1-.alpha.)O.sub.3 -PbTiO.sub.3 -PbZrO.sub.3 system is disclosed which comprises providing a piezoelectric ceramic composition expressed by the general formula:xPb(Sn.sub..alpha. Sb.sub.1-.alpha.)O.sub.3 -yPbTiO.sub.3 - zPbZrO.sub.3wherein subscripts .alpha., x and y are mole fractions of the respective components and have the following values, x+y+z= 1.00, 1/4.ltoreq..alpha..ltoreq.3/4, said composition falling within a polygonal area defined by points A, B, C, D and E in FIG. 3, forming powder of the composition into forming bodies, and firing the forming bodies in an oxygen atmosphere containing not less than 80 vol % of oxygen. The firing in the oxygen atmosphere is effected at a temperature not less than 1000.degree. C. A part of lead in the composition may be replaced with not more than 20 atomic percent of at least one metal selected from the group consisting of Ba, Ca, Sr and Cd.

Abstract: Adding compounds which form in the temperature range of 1000.degree. to 1250.degree. C. the eutectics CuO.Cu.sub.2 O or CuO.Cu.sub.2 O Me.sup.IV O.sub.2 to materials having a perowskite structure results in a reduction of the sintering temperature of the perowskite ceramic to between 1050.degree. and 1185.degree. C. For the perowskite ceramic the relevant materials are alkaline earth titanates, -zirconates, -stannates and mixed crystals thereof; Me.sup.IV O.sub.2 represents the oxides of the elements of group IV of the periodic system of elements.

Abstract: A dielectric ceramic composition for microwave applications consists essentially of a sintered mixture represented by the general formula:(1-x)MgTiO.sub.3 --x(Ca.sub.1-y Me.sub.y)TiO.sub.3wherein Me is at least one rare earth element selected from the group of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, and wherein x and y are molar fractions of respective components and take values within the following respective ranges: 0.03.ltoreq.x.ltoreq.0.15, 0.001.ltoreq.y.ltoreq.0.06. The composition is a fine-grained, dence ceramic and enables to produce microwave devices with high permittivity, high quality factor and small temperature coefficient of resonance frequency.