Abstract: Radioactive waste materials are converted into solid form by mixing the radioactive waste with a novel polymeric formulation which, when solidified, forms a solid, substantially rigid matrix that contains and entraps the radioactive waste. The polymeric formulation comprises, in certain significant proportions by weight, urea-formaldehyde; methylated urea-formaldehyde; urea and a plasticizer. A defoaming agent may also be incorporated into the polymeric composition. In the practice of the invention, radioactive waste, in the form of a liquid or slurry, is mixed with the polymeric formulation, with this mixture then being treated with an acidic catalyzing agent, such as sulfuric acid. This mixture is then preferably passed to a disposable container so that, upon solidification, the radioactive waste, entrapped within the matrix formed by the polymeric formulation, may be safely and effectively stored or disposed of.

Abstract: Athermopile for a microwatt thermoelectric generator suitable for implanting in the body. The thermopile comprises a series of semiconductive thermoelectric elements such as P- and N-type bismuth telluride deposited as a thin film on a substrate such as a polyimide by sputtering. After the thin film is deposited, the thermopile is heat treated to anneal the bismuth telluride. The thermopile is then ready for insertion in a microwatt thermoelectric generator.

Abstract: A microwatt thermoelectric generator suitable for implanting in the body. The disclosed generator utilizes a nuclear energy source. Provision is made for temporary electrical connection to the generator for testing purposes, and for ensuring that the heat generated by the nuclear source does not bypass the pile. Also disclosed is a getter which is resistant to shrinkage during sintering, and a foil configuration for controlling the radiation of heat from the nuclear source to the hot plate of the pile.

Abstract: A microwatt thermoelectric generator suitable for implanting in the body. The disclosed generator utilizes a nuclear energy source. Provision is made for temporary electrical connection to the generator for testing purposes, and for ensuring that the heat generated by the nuclear source does not bypass the pile. Also disclosed is a getter which is resistant to shrinkage during sintering, and a foil configuration for controlling the radiation of heat from the nuclear source to the hot plate of the pile.