The present invention relates to Mn-activated luminescent materials, to a process for preparation thereof and to the use thereof as luminophores or conversion luminophores in light sources. The present invention further relates to a radiation-converting mixture comprising the luminescent material of the invention and a light source comprising the luminescent material of the invention or the radiation-converting mixture. The present invention further provides light sources, especially LEDs, and lighting units comprising a primary light source and the luminescent material of the invention or the radiation-converting mixture. The Mn-activated luminescent materials of the invention are especially suitable for creation of warm white light in LEDs.

A method for enhancing radionuclide activity of a daughter radionuclide-containing eluate obtained from a mixture of mother/daughter radionuclides is disclosed. This method comprises i) contacting separation particles with an aqueous solution containing a mixture of mother and daughter radionuclides wherein daughter radionuclides bind to separation particles and mother radionuclides does not. That contact is maintained ii) for a time for unbound daughter radionuclide to bind to the separation particles. Unbound mother radionuclide is iii) separated from the daughter radionuclide-bound separation particles using a washing solution. Steps i) and ii) are repeated at least once iv). The bound daughter radionuclide is stripped v) from the separation particles using a volume of stripping solution less than that used if only steps i), ii), iii) and v) were used for each of the recited at least two separations to form an aqueous eluate having enhanced daughter radionuclide activity.

A method is provided which can separate rhenium from a solution containing rhenium by a simple procedure in a shorter time. A method of selectively recovering rhenium from a solution containing rhenium and one or more different metals is also provided. A method of recovering rhenium is used. The method involves (A) adding an electron donor (aliphatic secondary alcohol or aliphatic secondary thioalcohol) and a ketone compound to a solution containing perrhenate ions, (B) irradiating the solution after the addition step with ultraviolet light to precipitate a reduced species of the perrhenate ions contained in the solution, and (C) separating the reduced species of perrhenate ions from the solution, the reduced species being precipitated during the ultraviolet light irradiation.

A method for separating an amount of osmium from a mixture containing the osmium and at least one other additional metal is provided. In particular, method for forming and trapping OsO.sub.4 to separate the osmium from a mixture containing the osmium and at least one other additional metal is provided.

A method for separating an amount of osmium from a mixture containing the osmium and at least one other additional metal is provided. In particular, method for forming and trapping OsO.sub.4 to separate the osmium from a mixture containing the osmium and at least one other additional metal is provided.

Separation of rhenium disulfide nanomaterials and related fluid density gradient media.

Separation of rhenium disulfide nanomaterials and related fluid density gradient media.

Nanocrystalline metal powders comprising tungsten, molybdenum, rhenium or niobium can be synthesized using a combustion reaction. Methods for synthesizing the nanocrystalline metal powders are characterized by forming a combustion synthesis solution by dissolving in water an oxidizer, a fuel, and a base-soluble, ammonium precursor of tungsten, molybdenum, rhenium, or niobium in amounts that yield a soichiometric burn when combusted. The combustion synthesis solution is then heated to a temperature sufficient to substantially remove water and to initiate a self-sustaining combustion reaction. The resulting powder can be subsequently reduced to metal form by heating in a reducing gas environment.

The present disclosure relates to hydrometallurgical methods for the isolation and recovery of platinum from rhenium-containing materials, and more particularly, from superalloys containing rhenium, platinum, and other metals. The disclosure also relates to apparatuses capable of carrying out the hydrometallurgical methods and the product streams generated from the methods and apparatuses.

The invention provides a process for exfoliating a 3-dimensional layered material to produce a 2-dimensional material, said process comprising the steps of mixing the layered material in a solvent to provide a mixture; applying energy, for example ultrasound, to said mixture, and removing the energy applied to the mixture, such that sedimentation of the 2-dimensional material out of solution as a weakly re-aggregated, exfoliated 2-dimensional material is produced. The invention provides a fast, simple and high yielding process for separating 3-dimensional layered materials into individual 2-dimensional layers or flakes, which do not strongly re-aggregate, without utilising hazardous solvents.