Disclosed is a composition having nanoparticles or particles of a refractory metal, a refractory metal hydride, a refractory metal carbide, a refractory metal nitride, or a refractory metal boride, an organic compound consisting of carbon and hydrogen, and a nitrogenous compound consisting of carbon, nitrogen, and hydrogen. The composition, optionally containing the nitrogenous compound, is milled, cured to form a thermoset, compacted into a geometric shape, and heated in a nitrogen atmosphere at a temperature that forms a nanoparticle composition comprising nanoparticles of metal nitride and optionally metal carbide. The nanoparticles have a uniform distribution of the nitride or carbide.

A material including a body including B.sub.6O.sub.X can include lattice constant c of at most 12.318. X can be at least 0.85 and at most 1. In a particular embodiment, 0.90≤X≤1. In another particular embodiment, lattice constant a can be at least 5.383 and lattice constant c can be at most 12.318. In another particular embodiment, the body can consist essentially of B.sub.6O.sub.X.

A thermoelectric conversion material made of a sintered body containing a magnesium silicide as a major component includes: a magnesium silicide phase; and a magnesium oxide layer formed on a surface layer of the magnesium silicide phase, in which an aluminum concentrated layer having an Al concentration higher than an aluminum concentration in an inside of the magnesium silicide phase is formed between the magnesium oxide layer and the magnesium silicide phase, and the aluminum concentrated layer has a metallic aluminum phase including aluminum or an aluminum alloy.

High quality, catalyst-free boron nitride nanotubes (BNNTs) that are long, flexible, have few wall molecules and few defects in the crystalline structure, can be efficiently produced by a process driven primarily by Direct Induction. Secondary Direct Induction coils, Direct Current heaters, lasers, and electric arcs can provide additional heating to tailor the processes and enhance the quality of the BNNTs while reducing impurities. Heating the initial boron feed stock to temperatures causing it to act as an electrical conductor can be achieved by including refractory metals in the initial boron feed stock, and providing additional heat via lasers or electric arcs. Direct Induction processes may be energy efficient and sustainable for indefinite period of time. Careful heat and gas flow profile management may be used to enhance production of high quality BNNT at significant production rates.

A sintered MnZn ferrite comprising as main components 53.5 to 54.3% by mol of Fe calculated as Fe.sub.2O.sub.3, and 4.2 to 7.2% by mol of Zn calculated as ZnO, the balance being Mn calculated as MnO, and comprising as sub-components 0.003 to 0.018 parts by mass of Si calculated as SiO.sub.2, 0.03 to 0.21 parts by mass of Ca calculated as CaCO.sub.3, 0.40 to 0.50 parts by mass of Co calculated as Co.sub.3O.sub.4, 0 to 0.09 parts by mass of Zr calculated as ZrO.sub.2, and 0 to 0.015 parts by mass of Nb calculated as Nb.sub.2O.sub.5, per 100 parts by mass in total of the main components (calculated as the oxides), C.sub.(zn)/C.sub.(co) being 9.3 to 16.0 wherein C.sub.(zn) is the content of Zn contained as a main component (% by mol calculated as ZnO in the main components), and C.sub.(co) is the content of Co contained as a sub-component (parts by mass calculated as Co.sub.3O.sub.4 per 100 parts by mass in total of the main components).

The present application relates to the field of engineering ceramic materials, and specifically discloses a solid-phase-sintered silicon carbide article and a preparation method thereof. A method for preparing a solid-phase-sintered silicon carbide article includes the following steps: grinding of raw materials: mixing a micron-scale silicon carbide powder with a boron-containing sintering aid and wet grinding to obtain a slurry; spray granulating: adding a water-soluble carbon black and a binder to the slurry, stirring evenly, and spray granulating to obtain a granulated powder of silicon carbide; mixing; ageing: ageing the wet powder obtained by mixing to obtain a aged material; post-processing: subjecting the aged material to pugging, extruding, drying and heating.

A complex ceramic particle and ceramic composite material may be made of a pretreated coal dust and a polymer derived ceramic that is mixed together and pyrolyzed in a nonoxidizing atmosphere. Constituent portions of the particle mixture chemically react causing particles to increase in density and reduce in size during pyrolyzation, yielding a particle suitable for a plurality of uses including composite articles and proppants.

A ceramic honeycomb structure includes: an outer peripheral wall; and a partition wall disposed on an inner side of the outer peripheral wall, the partition wall defining a plurality of cells, each of the plurality of cells to form a fluid flow path extending from one end face to other end face. The honeycomb structure contains: 1) particles including one or more selected from silicon carbide, silicon nitride and aluminum nitride; and 2) silicon doped with a dopant. The dopant is a Group 13 element or a Group 15 element. The honeycomb structure has a silicon content (B) of from 20 to 80% by mass, and the honeycomb structure has a porosity of 30% or less.

A honeycomb structure includes: an outer peripheral wall; and partition walls disposed on an inner side of the outer peripheral wall, the partition walls defining a plurality of cells, each of the plurality of cells extending from one end face to the other end face to form a flow path for a fluid. The partition walls and the outer peripheral wall include ceramics containing at least silicon. A content of silicon in the ceramics is 30% by mass or more. A concentration of at least one dopant in the silicon is from 10.sup.16 to 5×10.sup.20/cm.sup.3.

A production method of boron carbide nano-sized particles and/or submicron particles includes the following sequential steps: obtention of a fluid mixture including elemental boron, glycerin and one or more carboxylic add, wherein a molar ratio of glycerin to the one or more carboxylic acids is within a range between 10:1 and 10:7.5. Heating of the fluid mixture to obtain a first mid-product in a form of a gel including borate ester bonds. Solidification of the first mid-product by heating a reaction product to obtain a second mid-product in solid form. Sintering the second mid-product to obtain boron carbide in a form of particles.