A general procedure applied to a variety of sol-gel precursors and solvent systems for preparing and controlling homogeneous dispersions of very small particles within each other. Fine homogenous dispersions processed at elevated temperatures and controlled atmospheres make a ceramic powder to be consolidated into a component by standard commercial means: sinter, hot press, hot isostatic pressing (HIP), hot/cold extrusion, spark plasma sinter (SPS), etc.

An apparatus and method for manufacturing solid particles based on inert gas evaporation. The method includes forming a continuous gaseous feed flow, and injecting the continuous gaseous feed flow through an inlet into a free-space region of a reactor chamber in the form of a feed jet flow, and forming at least one continuous jet flow of a cooling fluid and injecting the at least one jet flow of cooling fluid into the reaction chamber. The feed jet flow is made by passing the feed flow at a pressure above the reactor chamber pressure in the range from 0.01.Math.10.sup.5 to 20.Math.10.sup.5 Pa through an injection nozzle. The jet flow of cooling fluid is made by passing the cooling fluid through an injection nozzle which directs the jet flow of cooling fluid such that it intersects the feed jet flow with an intersection angle between 30 and 150°.

An apparatus and method for manufacturing solid particles based on inert gas evaporation. The method includes forming a continuous gaseous feed flow, and injecting the continuous gaseous feed flow through an inlet into a free-space region of a reactor chamber in the form of a feed jet flow, and forming at least one continuous jet flow of a cooling fluid and injecting the at least one jet flow of cooling fluid into the reaction chamber. The feed jet flow is made by passing the feed flow at a pressure above the reactor chamber pressure in the range from 0.01.Math.10.sup.5 to 20.Math.10.sup.5 Pa through an injection nozzle. The jet flow of cooling fluid is made by passing the cooling fluid through an injection nozzle which directs the jet flow of cooling fluid such that it intersects the feed jet flow with an intersection angle between 30 and 150°.

The present invention is directed to methods of transferring urea from an aqueous solution comprising urea to a MXene composition, the method comprising contacting the aqueous solution comprising urea with the MXene composition for a time sufficient to form an intercalated MXene composition comprising urea.

The present invention is directed to methods of transferring urea from an aqueous solution comprising urea to a MXene composition, the method comprising contacting the aqueous solution comprising urea with the MXene composition for a time sufficient to form an intercalated MXene composition comprising urea.

A method can be used for producing a powdery precursor material for an optoelectronic component having a first phase of the following general composition (Ca.sub.1-a-b-c-d-eZn.sub.dMg.sub.eSr.sub.cBa.sub.bX.sub.a).sub.2Si.sub.5N.sub.8, wherein X is an activator that is selected from the group of the lanthanoids and wherein the following applies: 0<a<1 and 0≦b≦1 and 0≦c≦ and 0≦d≦1 and 0≦e≦1. The method includes producing a powdery mixture of starting materials. The starting materials comprise ions of the aforementioned composition. At least silicon nitride having a specific surface area greater than or equal to 9 m/g is selected as a starting material and wherein the silicon nitride comprises alpha silicon nitride or is amorphous. The method also includes heat-treating the mixture under a protective gas atmosphere.

An (oxy)nitride phosphor powder has a fluorescence peak wavelength of 610 to 625 nm and also has higher external quantum efficiency than the conventional one. The (oxy)nitride phosphor powder includes an α-type SiAlON and aluminum nitride, represented by the compositional formula: Ca.sub.x1Eu.sub.x2Si.sub.12−(y+z)Al.sub.(y+z)O.sub.zN.sub.16−z wherein x1, x2, y, z fulfill the following formulae: 1.60≦x1+x2≦2.90, 0.18≦x2/x1≦0.70, 4.0≦y≦6.5, 0.0≦z≦1.0. The powder can additionally contain Li in an amount of 50 to 10000 ppm. The content of the aluminum nitride may be more than 0 mass % to less than 33 mass %.

An (oxy)nitride phosphor powder has a fluorescence peak wavelength of 610 to 625 nm and also has higher external quantum efficiency than the conventional one. The (oxy)nitride phosphor powder includes an α-type SiAlON and aluminum nitride, represented by the compositional formula: Ca.sub.x1Eu.sub.x2Si.sub.12−(y+z)Al.sub.(y+z)O.sub.zN.sub.16−z wherein x1, x2, y, z fulfill the following formulae: 1.60≦x1+x2≦2.90, 0.18≦x2/x1≦0.70, 4.0≦y≦6.5, 0.0≦z≦1.0. The powder can additionally contain Li in an amount of 50 to 10000 ppm. The content of the aluminum nitride may be more than 0 mass % to less than 33 mass %.

Provided is a method and system for making powdered Fe.sub.16N.sub.2. The method can include sealing iron powder and a fixed amount of ammonia (NH.sub.3) gas within a pressure vessel. The pressure of the fixed amount of ammonia gas in the pressure vessel can be elevated so that Fe.sub.16N.sub.2 can be formed from the iron powder. Use of a pressure vessel and a fixed amount of ammonia gas can provide economic and environmental benefits such as higher conversion rates of iron powder into Fe.sub.16N.sub.2, reduced ammonia gas use, and reclamation of used ammonia gas.

Phosphors include a CaAlSiN.sub.3 family crystal phase, wherein the CaAlSiN.sub.3 family crystal phase comprises at least one element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.