Proposed is a nuclear fuel pellet manufactured with UO.sub.2 powder and being in a cylindrical shape, the nuclear fuel pellet including: a dish (10) provided in a shape of a spherical groove having a predetermined curvature and a diameter of 4.8 to 5.2 mm at a center of each of top and bottom surfaces of the nuclear fuel pellet; a shoulder (20) provided in an annular plane along a rim of the dish (10); a first chamfer (310) provided along a rim of the shoulder (20) while being adjacent to the shoulder (20); and a second chamfer (320) provided along a rim of the first chamfer (310), wherein a width (SW) of the shoulder (20) is 0.4565 mm to 0.6565 mm, an angle between the first chamfer (310) and a horizontal plane is 2.0°, and an angle between the second chamfer (320) and the horizontal plane is 18.0°.

A method of preparing a fine powder of calcium lanthanoid sulfide is disclosed. The method includes spraying soluble calcium and lanthanoid salts into at least one precipitating solution to form a precipitate comprising insoluble calcium and lanthanoid salts, optionally, oxidizing the precipitate comprising insoluble calcium and lanthanoid salts, and sulfurizing the optionally oxidized precipitate to form a fine powder of calcium lanthanoid sulfide. An alternative method for forming the powder is by flame pyrolysis. The calcium lanthanoid sulfide powder produced by either method can have an impurity concentration of less than 100 ppm, a carbon concentration of less than 200 ppm, a BET surface area of at least 50 m.sup.2/g, and an average particle size of less than 100 nm.

An object shaping method includes a step of forming a powder layer using first powder, a step of placing second powder having an average particle diameter smaller than an average particle diameter of the first powder at a part of a region of the powder layer, and a first heating step of heating the powder layer in which the second powder is placed. The average particle diameter is equal to or larger than 1 nm and equal to or smaller than 500 nm, and the first heating step performs heating the powder layer at a temperature at which particles contained in the second powder are sintered or melted.

Microwave apparatus and methods provide for non-resonant microwave thermal processing that utilize non-resonant, cross polarized, slotted waveguide arrays in conjunction with a granular susceptor material to homogenously distribute microwave energy inside a microwave cavity, resulting in highly uniform temperature distributions and part heating profiles during processing.

Proposed are nuclear fuel pellets showing high oxidation resistance in a steam atmosphere and a method for manufacturing same. The method includes: preparing a powder mixture by mixing a sintering additive powder including Cr2O3, MnO, and SiO2 with a uranium dioxide powder; forming a molded body by subjecting the powder mixture to compression molding; and sintering the molded body in a weak oxidative atmosphere in which an oxygen potential is −581.9 kJ/mol to −218.2 kJ/mol. The nuclear fuel pellets contain 0.05% to 0.16% by weight of the sintering additive composed of Cr2O3, MnO, and SiO2. A liquid phase generated during the sintering accelerates grain growth and inhibits reaction between uranium dioxide with steam by forming a film at the grain boundary of the uranium dioxide. This reduces leakage of a fission material by improving high-temperature water vapor oxidation resistance at around 1204° C. in a loss-of-coolant accident condition.

Proposed are nuclear fuel pellets showing high oxidation resistance in a steam atmosphere and a method for manufacturing same. The method includes: preparing a powder mixture by mixing a sintering additive powder including Cr2O3, MnO, and SiO2 with a uranium dioxide powder; forming a molded body by subjecting the powder mixture to compression molding; and sintering the molded body in a weak oxidative atmosphere in which an oxygen potential is −581.9 kJ/mol to −218.2 kJ/mol. The nuclear fuel pellets contain 0.05% to 0.16% by weight of the sintering additive composed of Cr2O3, MnO, and SiO2. A liquid phase generated during the sintering accelerates grain growth and inhibits reaction between uranium dioxide with steam by forming a film at the grain boundary of the uranium dioxide. This reduces leakage of a fission material by improving high-temperature water vapor oxidation resistance at around 1204° C. in a loss-of-coolant accident condition.

Various embodiments of the disclosure provide methods using spark plasma sintering (SPS) at moderate temperatures and moderate pressures to fabricate high-density graphite material. The moderate temperatures may be temperatures not exceeding about 1200° C. The moderate pressures may be pressures not exceeding about 300 MPa. The high density exhibited by the resulting, sintered, high-density graphite material may be greater than about 1.75 g/cm.sup.3 (e.g., greater than about 2.0 g/cm.sup.3).

A type of composite material where the matrix material and additive are held together by covalently or non-covalently bound ligands is described. A particularly useful composite material covered by the present invention is a carbon nanotube-reinforced composite material where the matrix consists of a polymer, covalently attached to a linker, where said linker is non-covalently attached to the carbon nanotube. Methods for the preparation of such composite materials are provided.

A type of composite material where the matrix material and additive are held together by covalently or non-covalently bound ligands is described. A particularly useful composite material covered by the present invention is a carbon nanotube-reinforced composite material where the matrix consists of a polymer, covalently attached to a linker, where said linker is non-covalently attached to the carbon nanotube. Methods for the preparation of such composite materials are provided.

An antimicrobial material including a substrate and an antimicrobial mixed metal oxide, mixed metal sulfide, or mixed metal oxysulfide in and/or on the substrate is described, as well as antimicrobial coating materials and coatings formed therefrom. The antimicrobial material may be constituted in an antimicrobial surface of a surface-presenting substrate, to combat transmission and spread of microbial disease, e.g., disease mediated by microbial pathogens such as bacteria, viruses, and fungi. Antimicrobial mixed metal oxide, mixed metal sulfide, or mixed metal oxysulfide as described may be contacted with microorganisms to effect inactivation thereof.