Abstract: The counting accuracy of the Chicago Scalers, Models 961A and 961B, is a function of the bias setting of the limiter (V2). this report gives quantitative data supporting this thesis. A method of making bias settings is suggested. These tests were run at the suggestion of Mr. V. C. Hanson.

Abstract: Pure UO2F2 is made by reaction between anhydrous HF and pure UO3. Although it is difficult to prepare free of water, it is not very hygroscopic. Prolonged heating at 100-105 degrees releases 99.9% of the water in an aqueous solution; the rate of loss of water is very small after saturation is reached. X-ray diffraction data give a density of 6.2 for the solid. The density of a 1.004 M solution is 1.274; the density of a saturated solution (5.130 M) is 2.400. The densities of F-9 solutions have been calculated from the densities of ordinary aqueous solutions, and the values are compared graphically. Data on the solubility indicate that there is a small increase in the range 25-100 degrees. Recovery of pure F-9 from a solution is hampered by hydrolysis of U)2F2 to give HF. The HF may be held back by addition of UO3 or CaO; the use of the latter, however, makes more difficult the recovery of all the F-9. Molar conductivities of UO2F2 solutions at 25 degrees, as well as the specific conductivities of a 1 molar solution containing various concentrations of UO3, have been determined. The addition of UO3 lowers the conductivity. The low …