Uranium oxide, suspensions

J. J. Went and H. de Rruyn, The Design of a Small Scale Prototype of a Homogeneous Power Reactor Fueled with Uranium Oxide Suspension, in Proceedings of the International Conference on the Peaceful Uses of Atomic Energy, Vol. 3. New York United Nations, 1956. (P/936)... 

The systems used as sources for the fission fragments were either uranium oxide films, or very fine grains of these same oxides which can eventually give suspensions. Quartz fiber systems (38) in which uranium oxide is incorporated have been used as well. The radiochemical nitrogen fixation reaction which is realized by means of these systems is usually considered as homogeneous. 

A single-region converter fueled with natural or slightly enriched uranium oxide as a suspension avoids the problems of plutonium precipitation, phase separation, and corrosion mentioned above. The advantage of such a converter reactor for power production is the elimination of radiation damage and fuel bumup problems encountered with solid-fuel elements however, the problem of radiation damage to the reactor pressure vessel must be considered. 

Tuovinen, O.H. and Kelly, D.P., (1974 (a) (b) (c). Studies on the growth of Thiobacillus ferrooxidans. II. Toxicity of uranium to growing cultures and tolerance conferred by mutation, other metal cations and EDTA. Arch. Mikrobiol., 95 153—164. III. Influence of uranium, other metal ions and 2,4-dinitrophenol on ferrous iron oxidation and carbon dioxide fixation by cell suspensions, ibid, 95 165—180. IV. Influence of monovalent metal cations on ferrous iron oxidation and uranium toxicity in growing cultures, ibid, 98 167—174. 

In accordance with the present invention, a novel process and apparatus for establishment of a self-sustaining neutron chain reaction of neutrons with a neutron fissionable isotope such as U, and 94 2 is provided. The invention is particularly advantageous since it may be applied to establishment of such a reaction in compositions such as natural uranium where the concentration of fissionable material is low. Thus, we have found that a self-sustaining reaction may be established by use of a suspension of natural uranium in a liquid moderator containing about 0.0025 to 0.04 atom of uranium per molecule of a moderator such as deuterium oxide or about 0.0013 to 0.02 atom of uranium per atom of deuterium. Where the liquid moderator is less efficient, and absorbs more neutrons than deuterium oxide, this range of uranium concentration is somewhat narrower. 

Mercuric oxide. Uranium la precipitated rt en a suspension of mercuric oxide Is boiled In an aqueous solution containing ammonium chloride. Separation Is made from alkali metals and alkaline earths. Hydroxy acids Interfere. 

Mhere materials are labelled with an asterisk, a large number of powders were successfully deposited using the suspension medium described. Mizuguchi et al included alumina barium, strontium and calcium carbonates magnesia, zinc oxide, titanium dioxide, silica, indium oxide, lanthanum boride, tungsten carbide, cadmium sulfide and several metals and phosphors. The list of materials described by Gutierrez et al included several metals carbides of molybdenum, zirconium, tungsten, thorium, uranium, neptunium and plutonium zirconium hydride, tantalum oxide and uranium dioxide. In addition, many metallic and oxide powder suspensions in alcohols, acetone and dinitromethane were studied by Brown and Salt ... 

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