The application discloses a preparation method of monocrystal uranium dioxide nuclear fuel pellets, comprising: granulating and pelleting UO.sub.2 powder to obtain UO.sub.2 pellets; then coating surfaces of the UO.sub.2 pellets with monocrystal growth additive micro powder to form core-shell structure particles; and activated-sintering the core-shell structure particles at high temperature, liquefying the monocrystal growth additive on the surface of the core-shell structure particle at high temperature and then diffusing into UO.sub.2 pellets, dissolving the UO.sub.3 in the liquid monocrystal growth additive, and recrystallizing the UO.sub.2 to form the monocrystal UO.sub.2 nuclear fuel pellets.

The application discloses a preparation method of monocrystal uranium dioxide nuclear fuel pellets, comprising: granulating and pelleting UO.sub.2 powder to obtain UO.sub.2 pellets; then coating surfaces of the UO.sub.2 pellets with monocrystal growth additive micro powder to form core-shell structure particles; and activated-sintering the core-shell structure particles at high temperature, liquefying the monocrystal growth additive on the surface of the core-shell structure particle at high temperature and then diffusing into UO.sub.2 pellets, dissolving the UO.sub.3 in the liquid monocrystal growth additive, and recrystallizing the UO.sub.2 to form the monocrystal UO.sub.2 nuclear fuel pellets.

A method for producing a material based on silicon nanowires is provided. The method includes the steps of: i) bringing into contact, in an inert atmosphere, a sacrificial support based on a halogenide, a carbonate, a sulfate or a nitrate of an alkali metal, an alkaline earth metal or a transition metal having metal nanoparticles, with the pyrolysis vapours of a silicon source having a silane compound, by which silicon nanowires are deposited on the sacrificial support; and optionally ii) eliminating the sacrificial support and recovering the silicon nanowires produced in step ii).

Apparatuses and methods are provided for manufacturing diamond electronic devices. The apparatus includes a base comprising a water-block and a cover that at least partially covers the water-block. The apparatus includes a sample stage disposed on the base. The apparatus further includes a sample holder disposed on the sample stage and configured to accept a diamond substrate. The apparatus includes controlled thermal interfaces between water-block, sample stage, sample holder and diamond substrate.

A diode includes an n-type semiconductor layer including an n-type Ga.sub.2O.sub.3-based single crystal, and a p-type semiconductor layer including a p-type semiconductor in which a volume of an amorphous portion is higher than a volume of a crystalline portion. The n-type semiconductor layer and the p-type semiconductor layer form a pn junction.

A composite diamond body includes a diamond base material and a stable layer disposed on the diamond base material. The stable layer may have a thickness of 0.001 m or more and less than 10 m, and may include a plurality of layers. A composite diamond tool includes the composite diamond body. There are thus provided highly wear-resistant composite diamond body and composite diamond tool that are even applicable to mirror-finish planarization of a workpiece which reacts with diamond to cause the diamond to wear.

A composite diamond body includes a diamond base material and a stable layer disposed on the diamond base material. The stable layer may have a thickness of 0.001 m or more and less than 10 m, and may include a plurality of layers. A composite diamond tool includes the composite diamond body. There are thus provided highly wear-resistant composite diamond body and composite diamond tool that are even applicable to mirror-finish planarization of a workpiece which reacts with diamond to cause the diamond to wear.

The process for growing at least one semiconductor nanowire (3), said growth process comprising a step of forming, on a substrate (1), a nucleation layer (2) for the growth of the nanowire (3) and a step of growth of the nanowire (3). The step of formation of the nucleation layer (2) comprises the following steps: deposition onto the substrate (1) of a layer of a transition metal (4) chosen from Ti, V, Cr, Zr, Nb, Mo, Hf, Ta; nitridation of at least a part (2) of the transition metal layer so as to form a transition metal nitride layer having a surface intended for growing the nanowire (3).

A method of fabricating a plurality of single crystal CVD diamonds, the method comprising: coating a carrier substrate with a layer of polycrystalline CVD diamond material; bonding a plurality of single crystal diamond substrates to the layer of polycrystalline CVD diamond material on the carrier substrate; growing single crystal CVD diamond material on the plurality of single crystal diamond substrates to form a plurality of single crystal CVD diamonds; and separating the plurality of single crystal CVD diamonds from the layer of polycrystalline CVD diamond material on the carrier substrate and any polycrystalline CVD diamond material which has grown between the plurality of single crystal CVD diamonds to yield a plurality of individual single crystal CVD diamonds.

A window assembly heat transfer system is disclosed in which a window member has a selected transparency to monitored or sensed light wavelengths. One or more passages are provided in the window member for flowing a single-phase or two-phase heat transfer fluid, the passages being optically non-transparent to the monitored or sensed light wavelengths. A mechanism allows either evaporation or condensation of the fluid and/or balancing of a flow of the fluid within the passages. In one embodiment, the window assembly can be made by producing passages in a top surface of a first single plate, optionally producing passages in a bottom surface of a second single plate and bonding the top surface of the first plate to a bottom surface of a second single plate to form the window member with the passage or passages. In another embodiment, the window assembly can be made by providing a core around which the window member material is grown and thereafter removing the core to produce the passage or passages.