Abstract: Method of synthesis for a material made of particles having a core and a coating and/or being connected to each other by carbon cross-linking, the core of these particles containing at least one compound of formula LixM1?yM?y(XO4)n, in which x,y and n are numbers such as 0?x?2, 0?y?0.6 and 1?n?1.5, M is a transition metal, M? is an element with fixed valency, and the synthesis is carried out by reaction and bringing into equilibrium the mixture of precursors, with a reducing gaseous atmosphere, in such a way as to bring the transition metal or metals to the desired valency level, the synthesis being carried out in the presence of a source of carbon called carbon conductor, which is subjected to pyrolysis. The materials obtained have excellent electrical conductivity as well as very improved chemical activity.

Abstract: Improved solid acid electrolyte materials, methods of synthesizing such materials, and electrochemical devices incorporating such materials are provided. The stable electrolyte material comprises a solid acid in a eulytine structure capable of undergoing rotational disorder of oxyanion groups and capable of extended operation at elevated temperatures, that is, solid acids having hydrogen bonded anion groups; a superprotonic disordered phase; and capable of operating at temperatures of ˜100° C. and higher.

Abstract: A condensed phosphate containing an alkaline earth metal is caused to be present on the surface of titanium dioxide fine particles, and as a result, the condensed phosphate is firmly coupled with the fine particles and is barely liberated from the surface of the fine particles into a medium such as a binder or a resin. As a result, photo-functional particles exhibiting durability and dispersion stability are obtained. By use of the photo-functional particles, a powder and a slurry exhibiting excellent photo-functional property, durability, dispersion stability, and hydrophilicity are produced. In addition, by use of the powder and slurry, a polymer composition, a coating agent, a photo-functional formed article, and a photo-functional structure are produced.

Abstract: The present invention provides a novel process for producing a calcium phosphate cement or filler which hardens in a temperature dependent fashion in association with an endothermic reaction. In the reaction a limited amount of water is mixed with dry calcium phosphate precursors to produce a hydrated precursor paste. Hardening of the paste occurs rapidly at body temperature an is accompanied by the conversion of one or more of the reactants to poorly crystalline apatitic calcium phosphate. The hardened cements, fillers, growth matrices, orthopedic and delivery devices of the invention are rapidly resorbable and stimulate hard tissue growth and healing.

Abstract: The disclosed invention relates to novel crystalline compositions which may be obtained by doping the alpha (?) form of AlPO4 ceramics, which find use as piezoelectric materials, stable supports for catalysts, biotechnology uses, and the like.

Abstract: In a process of eluting phosphorus from sludge into a liquid phase and recovering the phosphorus efficiently, cell walls of microorganisms in the sludge are ruptured by a process selected from crushing sludge (for example, treating with an ultrasonic wave homogenizer), treating with ozone, and treating with heat. Then the liquid phase is treated with alkali, thereby eluting the phosphorus into a liquid phase efficiently in a short time. By coagulating and precipitating, the phosphorus eluted into the liquid phase is recovered.

Abstract: A condensed phosphate containing an alkaline earth metal is caused to be present on the surface of titanium dioxide fine particles, and as a result, the condensed phosphate is firmly coupled with the fine particles and is barely liberated from the surface of the fine particles into a medium such as a binder or a resin. As a result, photo-functional particles exhibiting durability and dispersion stability are obtained. By use of the photo-functional particles, a powder and a slurry exhibiting excellent photo-functional property, durability, dispersion stability, and hydrophilicity are produced. In addition, by use of the powder and slurry, a polymer composition, a coating agent, a photo-functional formed article, and a photo-functional structure are produced.

Abstract: Methods of making porous calcium phosphate bone replacement materials are discussed.

Abstract: A bone replacement material and therapy comprises the combination of calcium phosphate compounds and two or more soluble fillers in the form of fibers, mesh or other materials which have the dual functions of reinforcing an in vivo implant while dissolving at a programmed rate to form macropores capable of receiving natural bone ingrowth.

Abstract: Uniformly sized and shaped particles of metal salts are provided comprised of one or more metal cations in combination with one or more simple oxoacid anions and a general method for the controlled precipitation of said metal salts from aqueous solutions. The methods proceed via the in situ homogeneous production of simple or complex oxoacid anions in which one or more of the nonmetallic elements e.g. Group 5B and 6B (chalcogenides), and 7B (halides) comprising the first oxoacid anion undergo oxidation to generate the precipitant anionic species along with concurrent reduction of the nonmetallic element of a second, dissimilar oxoacid anion. The oxoacid anions are initially present in solution with one or more metal cations known to form insoluble salts with the precipitant anion.

Abstract: A bone replacement material and therapy comprises the combination of calcium phosphate compounds and two or more soluble fillers in the form of fibers, mesh or other materials which have the dual functions of reinforcing an in vivo implant while dissolving at a programmed rate to form macropores capable of receiving natural bone ingrowth.

Abstract: The invention relates to zirconium phosphate of H form which is characterized by a 31P NMR spectra comprising peaks at ?4.7 ppm, ?12.8 ppm and ?17.0 ppm (all peaks being in a range of ±0.5 ppm). Also featured is a Na form of the material. The zirconium phosphate material is characterized by a unique surface area, pore size distribution and surface morphology, as well as by an affinity for NH4+ ions and moisture insensitivity. Also featured is hafnium phosphate characterized by moisture insensitivity. The zirconium phosphate may be amorphous and possess a framework-type structure. The inventive method of making zirconium phosphate includes the steps of heating an aqueous mixture including a zirconium compound and a phosphorous-containing reagent at a temperature of at least 120° C. to form a reaction product, and treating the reaction product with acid at a temperature of at least 60° C.

Abstract: As-prepared AlPO4—B2O3—Na2O-based glasses were placed in an autoclave together with distilled water and were treated at 150° C. for two hours. Although the specific surface area of the as-prepared glass prior to autoclave treatment was negligibly small, the autoclave treatment dissolved most of the borate component and the sodium component to obtain a mesoporous material having a specific surface area of 236 m2/g and a pore size distribution of 5 to 10 nm. This mesoporous material is hydrophobic and has weak solid acidity and small polarity.

Abstract: The invention relates a process for producing an alkali metal nitrate and an alkali metal phosphate in the same process from a phosphate raw material and a nitrate raw material comprising the steps of: a) reacting the phosphate raw material with the nitrate raw material to provide an aqueous nitrophosphate feed, optionally followed by the separation of solid material, b) introducing the aqueous nitrophosphate feed into a first ion exchange step comprising an alkali metal-loaded cationic exchange resin for exchanging cations present in the feed with alkali metal ions present on the resin to obtain a stream enriched in alkali metal ions, c) subjecting the stream from step (b) to a first crystallization under such conditions that an alkali metal nitrate is crystallized and separating the crystallized alkali metal nitrate from the mother liquor, d) introducing the mother liquor from step (c) into a second ion exchange step comprising an alkali metal-loaded cationic exchange resin for exchanging cations present

Abstract: The invention provides a stable metal zirconium phosphates having formula (I), in which X is a metal or a combination of metals selected from Co, Mn, Ni, Cu, Cd, Fe, Cr, Al, Sn, V, Zn, Sc, Na, Mg, Ca and Si; and n has a molar value in the range of 1.25 to 22. These metal zirconium phosphates are prepared by sol-gel process.

Abstract: The invention relates to a hydroxylapatite material containing phosphate wherein the microporous structure of algae hard-tissue raw material is retained in the end product and which can be obtained by reacting an organic compound devoid of algae hard-tissue in an alkaline aqueous phosphate solution by adding magnesium ions at an elevated temperature. The invention also relates to a method for the production of said hydroxylapatite material containing tricalcium phosphate, which is characterized in that it is especially well resorbed in the body, is especially suitable as a bone substitute material or as a carrier material for active ingredients. Said material can also be used as a filter material.

Abstract: The present invention is directed to a synthetic biomaterial compound based on stabilized calcium phosphates and more particularly to the molecular, structural and physical characterization of this compound. The compound comprises calcium, oxygen and phosphorous, wherein at least one of the elements is substituted with an element having an ionic radius of approximately 0.1 to 1.1 ?. The knowledge of the specific molecular and chemical properties of the compound allows for the development of several uses of the compound in various bone-related clinical conditions.

Abstract: A method of making sodium zirconium carbonate is described which involves forming a mixture of zirconium oxychloride with soda ash and then heating at a sufficient temperature and for a sufficient time to form the sodium zirconium carbonate. Subsequent washing and filtration steps can further form parts of this process. A novel sodium zirconium carbonate is further described which contains from about 2 wt % to about 5 wt % Na+; from about 44 wt % to about 50 wt % ZrO2; from about 12 wt % to about 18 wt % CO32−; and from about 32 wt % to about 35 wt % H2O. Methods of making zirconium basic carbonate are further described which involve titrating an aqueous slurry of sodium zirconium carbonate to a pH of from about 3.5 to about 4.0 with an acidic agent wherein the sodium zirconium carbonate has a moisture content of from about 15% to about 25% LOD in solid form. The process further involves washing the aqueous slurry containing the formed zirconium basic carbonate with water.

Abstract: A new crystalline maganese phosphate composition having an empirical formula: Mn3(PO4)4.2(H3NCH2CH2)3N.6(H2O). The compound was determined to crystallize in the trigonal space group P-3c1 with a=8.8706(4) Å, c=26.1580(2) Å, and V (volume)=1783 Å3. The structure consists of sheets of corner sharing Mn(II)O4 and PO4 tetrahedra with layers of (H3NCH2CH2)3N and water molecules in-between. The pronated (H3NCH2CH2)3N molecules provide charge balancing for the inorganic sheets. A network of hydrogen bonds between water molecules and the inorganic sheets holds the structure together.

Abstract: The disclosed invention relates to novel crystalline compositions which may be obtained by doping the alpha (&agr;) form of AlPO4 ceramics, which find use as piezoelectric materials, stable supports for catalysts, biotechnology uses, and the like.

Abstract: A method of manufacturing a phosphate-bonded refractory product entirely during the mixing cycle by reacting phosphoric acid and alumina derived from one or more sources of finely divided reactive alumina, for example &bgr;-alumina and/or alumina hydroxide to form a proto aluminum orthophosphate gel or paste binder in the pan of a high-intensity mixer at ambient temperatures.

Abstract: The invention describes a method of preparing alpha- or beta-tricalcium phosphate, brushite (CaHPO4.2H2O), calcium pyrophosphate (Ca2P2O7) or hydroxyapatite (Ca5(PO4)3(OH)) or mixtures thereof in the form of morsels or granules via gelatin processing. These morsels or granules can be used as bone or tooth fillers or bone substitutes in applications, especially when higher rates of resorption or taking part in the bone remodelling processes of the implanted material are desired.

Abstract: The present invention relates to a method for preparation of the supersaturated calcium and phosphate ions solution and a method for preparation of the thin film of calcium phosphate crystal on solid surface by using the said solution. Particularly, the lowered temperature and/or the use of suitable buffer system inhibit the nucleation of calcium phosphate in aqueous solution, and thereby highly supersaturated calcium and phosphate ions solution can be prepared. And the thin film of calcium phosphate crystal on solid surface can be prepared with rapidity and good quality of high reactivity and low crystallinity by using the said solution. Also the thin film of calcium phosphate crystal prepared according to the present invention has biocompatibility and can be applied as biomaterials.

Abstract: The present invention relates to an inorganic compound with a lamellar structure, to its process of preparation and to its use in the reinforcement of macromolecular materials. It relates more specifically to a compound based on zirconium and/or titanium phosphate. The process for the preparation of the compound comprises a stage of treatment at a pH of between 3 and 9.

Abstract: A method of making sodium zirconium carbonate is described which involves forming a mixture of zirconium oxychloride with soda ash and then heating at a sufficient temperature and for a sufficient time to form the sodium zirconium carbonate. Subsequent washing and filtration steps can further form parts of this process. A novel sodium zirconium carbonate is further described which contains from about 2 wt % to about 5 wt % Na+; from about 44 wt % to about 50 wt % ZrO2; from about 12 wt % to about 18 wt % CO32−; and from about 32 wt % to about 35 wt % H2O. Methods of making zirconium basic carbonate are further described which involve titrating an aqueous slurry of sodium zirconium carbonate to a pH of from about 3.5 to about 4.0 with an acidic agent wherein the sodium zirconium carbonate has a moisture content of from about 15% to about 25% LOD in solid form. The process further involves washing the aqueous slurry containing the formed zirconium basic carbonate with water.

Abstract: In a method for synthesizing reduced metal compounds using electromagnetic radiation, starting materials comprising at least one particulate metal compound and at least one source of carbon are combined to form a mixture. The mixture is exposed to electromagnetic radiation to form a reaction product. Preferably, the carbon is a reducing carbon, and at least one metal of the starting materials is reduced in oxidation state during radiation exposure. Reducing carbon may be supplied by elemental carbon, by an organic material, or by mixtures. Preferably, the solid state reactants also include an alkali metal compound. The products of the method are preferably useful as cathode active materials in lithium ion batteries. The electromagnetic radiation is selected from among microwave, infrared, and radio frequencies of about 1 MHz to 3000 GHz.

Abstract: The invention relates to zirconium phosphate of H form which is characterized by a 31P NMR spectra comprising peaks at −4.7 ppm, −12.8 ppm and −17.0 ppm (all peaks being in a range of ±0.5 ppm). Also featured is a Na form of the material. The zirconium phosphate material is characterized by a unique surface area, pore size distribution and surface morphology, as well as by an affinity for NH4+ ions and moisture insensitivity. Also featured is hafnium phosphate characterized by moisture insensitivity. The zirconium phosphate may be amorphous and possess a framework-type structure. The inventive method of making zirconium phosphate includes the steps of heating an aqueous mixture including a zirconium compound and a phosphorous-containing reagent at a temperature of at least 120° C. to form a reaction product, and treating the reaction product with acid at a temperature of at least 60° C.

Abstract: A zirconium phosphate compound having a Zr:P ratio of from about 1.80-2.0 to 1, which compound's H-form exhibits a single peak at −13.7±0.5 ppm in the 31P NMR spectra. The compound is useful as a catalyst, catalyst support and ion exchange media having a high affinity for cobalt and nickel ions.

Abstract: The invention describes a wet-chemical process for the preparation of alpha- and beta-tricalcium phosphate (TCP) powders. The procedure simply comprises immediate addition of di-ammonium hydrogen phosphate to an aqueous solution of calcium nitrate tetrahydrate, or vice versa. Calcination of the recovered precursor powders at 800° C. in air produces beta-TCP, whereas the calcination of the same at 1200° C., followed by rapid cooling to room temperature yields submicron-particulated alpha-TCP powders. These powders can be the raw materials for bioceramics, such as artificial bones, artificial joints, artificial tooth roots, and calcium phosphate-based self-setting, self-hardening cements.

Abstract: Provided is a method for production of nanocrystalline hydroxyapatite particles, and nanocrystalline hydroxyapatite particles produced according to the method. The nanocrystalline hydroxyapatite particles exhibit substantially superior cell transformation abilities as compared to known and commercially-available calcium phosphate kits. The nanocrystalline hydroxyapatite particles also find use in tissue engineering applications, for example bone and tooth engineering and repair applications.

Abstract: Process for the preparation of a vanadium phosphate catalyst comprising treatment of a vanadium compound with formic acid, water and a phosphorus compound.

Abstract: The present invention is directed to a synthetic biomaterial compound based on stabilized calcium phosphates and more particularly to the molecular, structural and physical characterization of this compound. The compound comprises calcium, oxygen and phosphorous, wherein at least one of the elements is substituted with an element having an ionic radius of approximately 0.1 to 1.1 Å. The knowledge of the specific molecular and chemical properties of the compound allows for the development of several uses of the compound in various bone-related clinical conditions.

Abstract: A process for the preparation of a single phase magnesium- and carbonate-substituted hydroxyapatite composition, which process comprises the steps of (i) preparing an aqueous solution containing CO32− and PO43− ions in the substantial absence of cations other than H+ ions; (ii) mixing the solution from step (i) with an aqueous calcium- and magnesium-containing solution or suspension; and (iii) collecting and drying the precipitate formed in step (ii); the ratio of (Ca+Mg/P) in the calcium- and magnesium-containing solution or suspension and the phosphorus-containing solution, when mixed together, being maintained at 1.67, or above. The product of the process is novel and comprises up to 0.5% magnesium and up to 1% of carbonate substituted into the hydroxyapatite structure and which does not contain Na+ or NH4+ ions, the ratio of (Ca+Mg/P) being greater than 1.67.

Abstract: A process for the preparation of a single phase carbonate-substituted hydroxyapatite composition, which process comprises the steps of (i) preparing an aqueous solution containing Co32− and PO43− ions in the substantial absence of cations other than H+ ions: (ii) mixing the solution from step (i) with an aqueous solution or suspension of a calcium compound; and (iii) collecting and drying the precipitate formed in step (ii); the ratio of Ca/P in the calcium-containing solution or suspension and the phosphorus-containing solution, when mixed together, being maintained above 1.67. The product of the process is novel with a Ca/P molar ratio of greater than 1.67 and comprises up to 5% by weight of CO32− ions substituted in the B site or the B and A sites of the hydroxyapatite structure, with at least 50% of the CO32− ions being substituted on the B site. This product does not contain Na+ or NH4+ ions.

Abstract: Compositions including zirconium phosphate particles as well as methods of synthesizing and using same are provided. The zirconium phosphate particles are synthesized through the use of polyphosphate and zirconyl chloride.

Abstract: The present invention provides a method of manufacturing calcium phosphate powder comprising the steps of preparing a mixed material by mixing calcium hydroxide (Ca(OH)2) powder and calcium hydrogenphosphate powder so that a molar ratio (Ca/P) of calcium to phosphor is set to a range of 1.45-1.72; conducting a mixing/milling treatment to the mixed material to cause a soft-mechanochemical compositing reaction thereby to prepare a calcium phosphate precursor; and conducting a heat treatment to thus obtained precursor at a temperature of 600° C. or more thereby to prepare calcium phosphate powder. According to the present invention, the manufacturing process is simple and the manufacturing cost can be remarkably reduced. In addition, fine calcium phosphate powder excellent in characteristics can be easily manufactured in a short time.

Abstract: A method for the conditioning of phosphoric acid containing solutions is described, wherein the solution is converted to a solid material by adding an aluminum compound. This solid material can readily be stored in disposal sites because it is not water-soluble. This method is particularly suited for the conditioning of phosphoric acid containing solutions from metal processing. An apparatus (10) for carrying out the method comprises a mixing tube (12) with a longitudinal axis (M) as well as an inlet (14) and an outlet (16). At least two liquid supply nozzles (18 and 20) opens into the mixing tube inlet (14) and, with respect to the inlet cross-sectional area of same, into a central area. Moreover, at least one gas supply nozzle (22) which is arranged radially outward of the liquid supply nozzles (18 and 22) opens into the mixing tube inlet (14). The longitudinal axis (G) of each gas supply nozzle (22) is inclined relative to the longitudinal centre axis (M) in such manner that said axes do not intersect.

Abstract: The present invention provides delivery vehicles comprising a synthetic, poorly crystalline apatite (PCA) calcium phosphate and a biologically active agent. The PCA calcium phosphate offers many advantages over known delivery materials and is particularly useful for delivery of agents to bone sites, the central nervous system, intramuscular sites, subcutaneous sites, interperitoneal sites, and occular sites. The invention also provides methods of preparing delivery vehicles, of altering delivery vehicle characteristics, and of delivering biologically active agents to a site. The invention is useful for both medical and veterinary applications.

Abstract: A solid powder product with a Ca/P ratio of between 1.40 and 1.90 is prepared from tricalcium phosphate and tetracalcium phosphate. An aqueous solution containing calcium ions and phosphate ions with a Ca/P ratio higher than 0.20 and lower than 0.50 is prepared. The aqueous solution and the solid powder product and optionally water are mixed to obtain a mixture with a liquid/solid weight ratio of between 0.30 and 0.65 and a resulting paste with a Ca/P ratio of between 1.50 and 1.67.

Abstract: The present invention relates to methods for the preparation of inorganic nanoparticles capable of fluorescence, wherein the nanoparticles consist of a host material that comprises at least one dopant. The synthesis of the invention in organic solvents allows to gain a considerably higher yield compared to the prior art synthesis in water. All kinds of objects can advantageously be marked and reliably authenticated by using an automated method on the basis of a characteristic emission. Further, the size distribution of the prepared nanoparticles is narrower which renders a subsequent size-selected separation process superfluous.

Abstract: A method of manufacturing a phosphate-bonded refractory product entirely during the mixing cycle by reacting phosphoric acid and alumina derived from one or more sources of finely divided reactive alumina, for example &bgr;-alumina and/or alumina hydroxide to form a proto aluminum orthophosphate gel or paste binder in the pan of a high-intensity mixer at ambient temperatures.

Abstract: Nanoscale and submicron particles have been produced with polyatomic anions. The particles can be crystalline or amorphous. The particles are synthesized in a flowing reactor, preferably with an intense light beam driving the reaction. In preferred embodiments, the particles are highly uniform. Batteries can be formed from submicron and nanoscale lithium metal phosphates. Coatings also can be formed from the particles.

Abstract: Process for the preparation of a vanadium phosphate catalyst comprising treatment of a vanadium compound with formic acid, water and a phosphorus compound.

Abstract: This invention relates to novel sol-gel calcium phosphate, in particular hydroxyapatite ceramic coatings and processes of making same at low temperature. Such coatings are useful, inter alia, for dental implants and bone-metal contact appliances. A sol-gel process for preparing a crystallized hydroxyapatite which comprises: (a) hydrolysing a phosphor precursor in a water based medium; (b) adding a calcium salt precursor to the medium after the phosphite has been hydrolysed to obtain a hydroxyapatite gel; and (c) calcining the crystallized hydroxyapatite at a suitable elevated temperature.

Abstract: The present invention relates to the use of a compound based on a thulium-containing lanthanum phosphate as a phosphor in a plasma or X-ray system. This phosphate may furthermore contain gadolinium. The thulium content of the compound, expressed in at % with respect to the lanthanum, is between 0.1 and 10, more particularly between 0.5 and 5. The invention also covers a lanthanum phosphate which is characterized in that it contains thulium and in that it consists of particles having a mean size of between 1 and 20 &mgr;m with a dispersion index of less than 0.6.

Abstract: A process for removing impurities contained in the crystal lattice of minerals, comprising the steps of forming a mixture of a mineral capable of structurally reorganizing its crystal lattice which contains an impurity in its crystal lattice and a halogen anion, and water; heating the mixture to the mineral's structural reorganization transition temperature; holding the mixture at the structural reorganization transition temperature for a sufficient period of time to allow the impurity to freely migrate from the lattice to combine with the halogen anion; and separating the combined impurity and anion from the mixture to render the mineral essentially free of the impurity. The process is applicable to numerous minerals and impurities, but is especially useful to remove arsenic from fluorspar. Numerous halogen anions can be employed, such as chlorides, fluorides, bromides and iodides, but the preferred halogen anion is a metal chloride such as calcium chloride.

Abstract: A hydroxyapatite consisting substantially of Ca10(PO4)6(OH)2, and having a crystal structure which has at least two diffraction peaks at 31-32 degrees and 26 degrees in X-ray diffractometry; and a process for producing a hydroxyapatite which comprises the step (A) of immersing a substrate in a first aqueous solution containing calcium ions and a second solution containing PO4 ions to generate the hydroxyapatite at least on the surface of the substrate and the step (B) of recovering the hydroxyapatite from the substrate.

Abstract: Uniformly sized and shaped particles of metal salts are provided comprised of one or more metal cations in combination with one or more simple oxoacid anions and a general method for the controlled precipitation of said metal salts from aqueous solutions. The methods proceed via the in situ homogeneous production of simple or complex oxoacid anions in which one or more of the nonmetallic elements e.g. Group 5B and 6B (chalcogenides), and 7B (halides) comprising the first oxoacid anion undergo oxidation to generate the precipitant anionic species along with concurrent reduction of the nonmetallic element of a second, dissimilar oxoacid anion. The oxoacid anions are initially present in solution with one or more metal cations known to form insoluble salts with the precipitant anion.

Abstract: A biphasic cement of &agr;-TCP/HAP is primarily composed of 30-60 wt % &agr;-tricalcium phosphate (Ca3(PO4)2, &agr;-TCP) and 40-70 wt % of hydroxyapatite (Ca10(PO4)6(OH)2, HAP). The biphasic cement of &agr;-TCP/HAP of the present invention is superior since it can set rapidly while soaking in a water solution. The present invention also provides a process for preparing the biphasic cement of &agr;-TCP/HAP, in which the composition of the biphasic cement of &agr;-TCP/HAP can be controlled.

Abstract: Uniformly sized and shaped particles of metal salts are provided comprised of one or more metal cations in combination with one or more simple oxoacid anions and a general method for the controlled precipitation of said metal salts from aqueous solutions. The methods proceed via the in situ homogeneous production of simple or complex oxoacid anions in which one or more of the nonmetallic elements e.g. Group 5B and 6B (chalcogenides), and 7B (halides) comprising the first oxoacid anion undergo oxidation to generate the precipitant anionic species along with concurrent reduction of the nonmetallic element of a second, dissimilar oxoacid anion. The oxoacid anions are initially present in solution with one or more metal cations known to form insoluble salts with the precipitant anion.