Air Scattering of Co60 Gamma Rays: Theory Versus Experiment (open access)

Air Scattering of Co60 Gamma Rays: Theory Versus Experiment

For Co60 source at 15 meters, the air-scattered gamma dose rate predicted by theory is excerpted from ORNL-1575, pp. 167-203. This is compared with experimental measurements for the same source and comparable geometry reported by Convair in CVAC-170T. After applying an appropriate correction for ground scattering as estimated in Mart-55-16T (Convair), the two results are found to be in substantial agreement.
Date: April 17, 1958
Creator: Moran, Rubert S.
System: The UNT Digital Library
Development of the Excer Process (open access)

Development of the Excer Process

Two revised Excer process flowsheets are presented for the production of UF4 from urnayl nitrate solution. In both, the uranium is sorbed on a cation-exchange resin and eluted with aqueous HF. In one, the resulting UO2F2 in dilute HF is mixed with dilute sulfuric or hydrochloric acid and electrolytically reduced in a cation-exchange-membrane cell, and the precipitated UF4·0.75H2O is dried and dehydrated to anhydrous UF4. A cost of 20¢ per pound of reduced uranium is estimated. In the other, ammonium fluoride is also added to the uranyl fluoride solution before the electrolytic reduction step, and the precipitate is UF4·04NH4F. A flowsheet for preparing UF4 from raw ore is also shown. The uranium is sorbed on an anion-exchange resin from a sulfuric acid leach liquor and eluted with dilute HCl. Ammonium fluoride and HF are added to the UO2Cl2-HCl solution before the uranyl ion is electrolytically reduced to precipitate UF4·0.4NH4F. Decontamination factors as high as 45 and 9 for gross beta and gamma activities and of 10 to 5000 for light metal impurities were obtained in the electrolytic reduction step.
Date: April 17, 1956
Creator: Marinsky, J. A.
System: The UNT Digital Library
The Isolation and Purification of Americium (open access)

The Isolation and Purification of Americium

Gram amounts of americium were separated quantitatively from kilogram quantities of lanthanum to yield an americium product approaching 90% purity. The remaining impurity was chiefly yttrium. Elution of americium from 25% loaded Dowex 50 resin column with 0.15 M citric acid— 0.10 M diammonium citrate — 0.3 M ammonium nitrate, pH 3.3 gave a product containing 99% of the americium with a La/Am ratio of 1/100 or less in one fourth of a column volume, in this case about 1 100-fold volume reduction. Approximately 9 g of americium was purified by this method. Elution with 12.8 M hydrochloric acid from a 20 to 30% loaded column gave 90% of the americium in two column volumes of product with a La/Am ratio of about 1/4. About 1 g of americium was purified by this method.
Date: April 17, 1956
Creator: Campbell, D. O.
System: The UNT Digital Library