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The large class of amorphous insoluble hydrous oxides has interesting ion exchange properties. These materials have high capacities and suitable exchange rates and may therefore be used in packed columns in typical chromatographic (ion exchange) manner. Hydrous oxides may exhibit either cation exchange or anion exchange properties, or both. The type of adsorption depends on the element on which the oxide is based, on the acidity of the medium and, to some extent, on the ion adsorbed. Though some of the most acidic oxides are soluble (e.g., P/sub 2/O/sub 5/) or easily dispersible (e.g., MoO/sub 3/ WO/sub 3/) their intrinsic cation exchange properties may be utilized by incorporating them in excess into an insoluble matrix, i.e., by preparing certain insoluble acidic salts. Some of the materials with cation exchange properties may be used even with extremely small columns - for the separation of the alkali metals from each other - or of the alkaline earths. The specificity of these compounds for cesium in acidic solutions permits the almost unique isolation of this element from properties all others. Those oxides with anion exchange properties also have unusual selectivities compared with the organic ion exchangers. Oxides based on Bi(III) have high selectivities …

Pyrometallurgical methods studied are liquation, self-drossing and filtration, slagging by the addition of oxide, carbide, or halide, liquid metal extraction, complete conversion to halide, followed by filtration and selective reduction of the plutonium, and electrorefininng. Experimental techniques and results are presented for each method. (auth)

Radiochemical studies of the fast neutron fission of U/sup 235/ and U/sup 238/ have been made in the mass region beyond mass 143 with two neutron energy distributions. These studies provide measurements of the relative fission yields of several chains in the rare earth group in fission of U/sup 235/ and U/sup 238/ caused by neutrons with an energy distribution very close to unmoderated fission neutrons and by neutrons with an energy distribution peaked at 8 Mev. The increased contribution of very asymmetric modes of fission as the energy of the compound nucleus is increased is clearly shown by the results. In the fission of U/sup 238/ the yield at mass 161 is increased 2.9 times at the higher neutron energy. No previous measurements have been published on radiochemical studies of the fission of U/sup 238/at these neutron energies beyond mass 144 except at mass 156 for the lower neutron energy. (auth)

This paper discusses research and development effort on a direct-cycle air-cooled nuclear reactor and propulsion equipment. The reactor experiment was designed, constructed, and tested during the period 1953 to 1956 to prove the feasibility of operating a turbojet engine from the heat produced by an air-cooled reactor. A description is given of the reactor, turbomachinery, shielding, control system, and associated equipment used in the first propulsion system test which was run in 1956. The system consisted of a modified J-47 turbojet engine arranged so that compressed air from the compressor was ducted through a shielded reactor and a chemical combustor in series before passing through the turbine and exhaust nozzle. The experimental reactor was based on a unique design concept in which water moderated at low temperature is contained in an aluminum core structure. The air-cooled metal fuel elements containing enriched uranium were arranged in passages running through the reactor. Thermal insulation was provided to protect the aluminum structure from the high temperature fuel elements and air, and to reduce heat losses to the moderator water. The entire reactor shield and turbojet assembly was mounted on a four-rail flat car for easy transfer by a shielded locomotive from the test …