Abstract:
A random laser comprising a substrate and a rare earth-doped glass fabricated on the substrate in the form of a waveguide, wherein the glass comprises a germanium glass, a titanium glass, or a chalcogenide glass.
Abstract:
The present invention seeks to improve beneficiation of a titanium oxide-containing composition (such as a low-grade or highly radioactive TiO2 ore) by combining a roasting and selective leaching steps.
Abstract:
An improved process for recovering a titanium dioxide product from a titanium oxide-containing roasted mass of the type derived from roasting an ilmenite, anatase or perovskite ore by exploiting an organic acid, such as mixture of oxalic acid and ascorbic acid.
Abstract:
The present invention relates to a zero-waste process for extraction of alumina from different types of bauxite ores and red mud residues and of titanium dioxide from ilmenite. Iron oxide is first reduced to metallic iron above the melting point of C-saturated cast iron alloy which yields a high-C iron alloy and an Al and Ti metal oxide rich slag which is then treated with alkali carbonate to form alkali aluminates and titanates. The alkali aluminates are separated by water leaching from which the hydroxide of alumina is precipitated by bubbling CO2. The residue from water leaching is treated with sulphuric acid and TiO2 is precipitated via a hydrolysis route. The process recovers most of the metal values and generates only small quantities of silicious residues at pH4-5 which can be used for soil conditioning. The present also relates to a method for selective separation of TiO2-rich oxides from titaniferrous ore/residue materials via oxidative roasting in the presence of alkali carbonate or carbonates followed by aqueous leaching of the roasted material and selective precipitation of TiO2 under controlled condition below pH=4.
Abstract:
The present invention relates to a photosensitive composition comprising synthetic nanocrystalline hydroxyapatite or a synthetic precursor thereof doped with a rare earth ion, the use of the composition in restorative or cosmetic dentistry, a process for preparing the composition and a method of generating an image of an exposed dentinal surface of a tooth.
Abstract:
This invention relates to a process for beneficiating a titaniferous ore. The process comprises calcining the titaniferous ore, at least one alkali or alkaline earth metal salt, and at least one alumina-containing material in the presence of oxygen to form a calcined ore mixture, then leaching the calcined ore mixture with a solution comprising ammonium, sodium or magnesium chloride in the presence of oxygen to form a leached ore mixture, and contacting the leached ore with an acid to form a beneficiated ore.
Abstract:
This invention relates to a process for beneficiating a titaniferous ore. The process comprises calcining the titaniferous ore, at least one alkali or alkaline earth metal salt, and at least one alumina-containing material in the presence of oxygen to form a calcined ore mixture, then leaching the calcined ore mixture with a solution comprising ammonium, sodium or magnesium chloride in the presence of oxygen to form a leached ore mixture, and contacting the leached ore with an acid to form a beneficiated ore.
Abstract:
This invention relates to halide glasses which have particular utility as hosts for rare earth elements in order to provide optical amplification by laser activity. The glasses are characterized in that the metal content is similar to conventional ZBLAN glasses except that it has been discovered that the replacement of Al by Y and In and the use of more than one alkali metal fluoride, e.g., NaF, CsF and LiF, has synergistic benefits. The synergistic benefits are good lasing performance (due to the low content of aluminum) and good stability in spite of the low content of aluminum. Pr.sup.3+ constitutes a good lasing species for amplifying telecommunications signals at 1300 nm using pump radiation at 1020 nm.
Abstract:
The present invention relates to a zero-waste process for extraction of alumina from different types of bauxite ores and red mud residues and of titanium dioxide from ilmenite. Iron oxide is first reduced to metallic iron above the melting point of C-saturated cast iron alloy which yields a high-C iron alloy and an Al and Ti metal oxide rich slag which is then treated with alkali carbonate to form alkali aluminates and titanates. The alkali aluminates are separated by water leaching from which the hydroxide of alumina is precipitated by bubbling C02. The residue from water leaching is treated with sulphuric acid and Ti02 is precipitated via a hydrolysis route. The process recovers most of the metal values and generates only small quantities of silicious residues at pH 4-5 which can be used for soil conditioning. The present also relates to a method for selective separation of Ti02-rich oxides from titaniferrous ore/residue materials via oxidative roasting in the presence of alkali carbonate or carbonates followed by aqueous leaching of the roasted material and selective precipitation of Ti02 under controlled condition below pH=4.
Abstract:
The present invention relates to a method for determining the extent of electrochemical extraction of a metal (M) from a metal (M) oxide caused by a voltage applied between a cathode comprising (or consisting essentially of) or in contact with the metal (M) oxide and an inert metal alloy anodein an oxygen-dissolving molten electrolyte.