A method and system are provided for the creation of vertical and horizontal freeze wells, in a dome-like pattern around the ore body, as a hydraulic barrier to ensure the ISR mining solution and the mined minerals do not flow out of the ore body. A method to formulate a suitable mining solution used for ISR mining, where the lixivant does not freeze when using the freeze dome containment method and where the resulting PLS has a high concentration of dissolved minerals and thus eliminates the need for the solvent extraction/ion exchange step during processing is also described.

Electrical devices operating in a range of 273 C. to 100 C. are disclosed. The devices include an insulating substrate. A U0.sub.2+x crystal or oriented crystal U0.sub.2+x film is on a first portion of the substrate. The U0.sub.2+x crystal or film originates and hosts a non-equilibrium polaronic quantum phase-condensate. A first lead on a second portion of the substrate is in electrical contact with the U0.sub.2+x crystal or film. A second lead on a third portion of the surface is in electrical contact with the U0.sub.2+x crystal or film. The leads are isolated from each other. A U0.sub.2+x excitation source is in operable communication with the UO.sub.2+x crystal or film. The source is configured to polarize a region of the crystal or film thereby activating the non-equilibrium quantum phase-condensate. One source state causes the UO.sub.2+x crystal or film to be conducting. Another source state causes the U0.sub.2+x crystal or film to be non-conductive.

Electrical devices operating in a range of 273 C. to 100 C. are disclosed. The devices include an insulating substrate. A U0.sub.2+x crystal or oriented crystal U0.sub.2+x film is on a first portion of the substrate. The U0.sub.2+x crystal or film originates and hosts a non-equilibrium polaronic quantum phase-condensate. A first lead on a second portion of the substrate is in electrical contact with the U0.sub.2+x crystal or film. A second lead on a third portion of the surface is in electrical contact with the U0.sub.2+x crystal or film. The leads are isolated from each other. A U0.sub.2+x excitation source is in operable communication with the UO.sub.2+x crystal or film. The source is configured to polarize a region of the crystal or film thereby activating the non-equilibrium quantum phase-condensate. One source state causes the UO.sub.2+x crystal or film to be conducting. Another source state causes the U0.sub.2+x crystal or film to be non-conductive.

The method described herein may be characterized as reacting uranium dioxide with carbon to produce uranium carbide, and, reacting the uranium carbide with a silane, a silicon halide, a siloxane, or combinations thereof, and excess hydrogen to produce uranium silicide.

A multiphase composite, formed by freeze-casting, lyophilization, and sintering, has sintered particles forming a scaffold having at least one region of aligned porosity; and a second phase formed in pores of the scaffold. In a particular embodiment, the second phase is a nuclear fuel, in another, the first phase is a nuclear fuel, and in others, both phases are nuclear fuels. In some embodiments, the first phase is a ceramic, and in other embodiments a metal such as stainless steel. In other embodiments, the second phase is a metal, and in other embodiments a ceramic. In some embodiments the second phase is positioned in a subset of pores of the scaffold, at least some additional pores being filled with a third phase. In embodiments, the second phase is also sintered.

A multiphase composite, formed by freeze-casting, lyophilization, and sintering, has sintered particles forming a scaffold having at least one region of aligned porosity; and a second phase formed in pores of the scaffold. In a particular embodiment, the second phase is a nuclear fuel, in another, the first phase is a nuclear fuel, and in others, both phases are nuclear fuels. In some embodiments, the first phase is a ceramic, and in other embodiments a metal such as stainless steel. In other embodiments, the second phase is a metal, and in other embodiments a ceramic. In some embodiments the second phase is positioned in a subset of pores of the scaffold, at least some additional pores being filled with a third phase. In embodiments, the second phase is also sintered.

The invention relates to the ROANEX method, which extracts actinides from used nuclear fuel in a single purification cycle. The used nuclear fuel contains actinides, U, Am, Pu, Np. and Cm, and fission products, Cs, Sr and Tc. The fission products are separated first from the used nuclear fuel. The actinides are reduced to their lowest oxidation states and then oxidized to their highest oxidations states. Uranium, Pu and Np move to an organic phase solution and Am and Cm move to a nitrate solution. Uranium, Pu, and Np are stripped from the organic phase solution, and then treated with an oxalic acid to form a precipitate. Americium and Cm are treated with a potassium carbonate solution and Am precipitates. Actinides Am, U, Pu, and Np precipitates are heated in an oven and then blended together to form a mixed oxide fuel of UO.sub.2, PuO.sub.2, NpO.sub.2 and AmO.sub.2.

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 multiphase composite, formed by freeze-casting, lyophilization, and sintering, has sintered particles forming a scaffold having at least one region of aligned porosity; and a second phase formed in pores of the scaffold. In a particular embodiment, the second phase is a nuclear fuel, in another, the first phase is a nuclear fuel, and in others, both phases are nuclear fuels. In some embodiments, the first phase is a ceramic, and in other embodiments a metal such as stainless steel. In other embodiments, the second phase is a metal, and in other embodiments a ceramic. In some embodiments the second phase is positioned in a subset of pores of the scaffold, at least some additional pores being filled with a third phase. In embodiments, the second phase is also sintered.