Abstract: Disclosed herein is a dual density disc comprising a dense outer tube comprising alumina having a purity of greater than 99%; and a porous core comprising alumina of a lower density than a density of the dense outer tube; wherein the porous core has an alumina purity of greater than 99%. Disclosed herein too is method comprising disposing in a dense outer tube a slurry comprising alumina powder and a pore former; heating the dense outer tube with the slurry disposed therein to a temperature of 300 to 600° C. to activate the pore former; creating a porous core in the dense outer tube; and sintering the dense outer tube with the porous core at a temperature of 800 to 2000° C. in one or more stages.

Abstract: Disclosed herein is a dual density disc comprising a dense outer tube comprising alumina having a purity of greater than 99%; and a porous core comprising alumina of a lower density than a density of the dense outer tube; wherein the porous core has an alumina purity of greater than 99%. Disclosed herein too is method comprising disposing in a dense outer tube a slurry comprising alumina powder and a pore former; heating the dense outer tube with the slurry disposed therein to a temperature of 300 to 600° C. to activate the pore former; creating a porous core in the dense outer tube; and sintering the dense outer tube with the porous core at a temperature of 800 to 2000° C. in one or more stages.

Abstract: Disclosed herein is a porous membrane comprising a porous substrate; a porous ceramic coating disposed on the porous substrate; where an average pore size of pores in the porous substrate are larger than an average pore size of pores in the porous coating. Disclosed herein is a method of manufacturing a porous membrane comprising disposing upon a porous substrate a porous ceramic coating, where the porous ceramic coating has an average pore size that is less than an average pore size of the porous substrate.

Abstract: The present disclosure provides a disposal container for nuclear materials. According to certain ambodiments, the disposal container includes a nuclear material sub-container of a first type and a plurality of nuclear material sub-containers of a second type. In particular implementations, the disposal container includes a plurality of nuclear material sub-containers of a first type. The nuclear material sub-containers of a second type may surround the nuclear material sub-container of a first type. In particular examples, the nuclear material sub-containers of a second type are arranged concentrically around the nuclear material sub-container of a first type. The disclosed disposal containers may provide more efficient storage of nuclear materials, such as nuclear waste.