Technical report with short reports covering (1) Effect of radiation on water and aqueous systems; (2) Effect of neutrons on graphite; (3) Effect of radiation on solid compounds; and (4) Scattering, stopping-power, ion-pair production, etc.

Abstract. thorium can be precipitated as a salt of p-dimethylaminoazophenylarsonic acid at a pH of about 1.5. the precipitate, collected on a sintered glass filter is washed with dilute ammonium hydroxide to dissolve the dye. the amount of thorium is determined by measuring the concentration of the dye spectrophotometrically at a wavelength of 450 millimicrons. Zirconium, which interferes, can be separated and determined using the same reagent in strong hydrochloric. the behavior of thorium metal upon treatment with various acids and upon fusion withKHSO4 is described. three satisfactory procedures are given for dissolving the metal with sulfuric acid, phosphoric acid, and by a potassium hydrogen sulfate fusion. The laboratory was presented with the problem of analyzing for a large number of elements in O2 metal. the results of a systematic study of methods for effecting solution of the metal are offered here since they may be of some interest and use to other laboratories. The four methods which effected complete solution of the metal are (1) Sulfuric acid method; (2) Fusion method; (3) Phosphoric acid method; and (4) Nitric acid-hydrofluoric acid method.

Abstract. Thorium peroxide was precipitated from thorium nitrate solutions containing varying amounts of sulfate ion and of hydrogen ion. The washed solids were analyzed both wet and dry. Analyses were made for thorium, peroxide oxygen, sulfate, nitrate, and water contents. X-ray powder photographs of the dried samples by W.H. Zachariasen showed the presence of only two phases. When precipitated from high sulfuric acid, the solid phase was isomorphous with Th(OO)SO4.3H20. More weakly acid solutions whose sulfate content was varied over wide limits [SO4--/Th(IV) (in solution before precipitation) = 0.005 to 67.0] yielded a solid, isomorphous with thorium peroxide nitrate and containing 3.0 to 3.8 peroxide oxygen atoms for each thorium atom. The sulfate content of this latter phase varied continuously between the limits SO4--/Th(IV) = 0.34 to 0.01 with nitrate ion present when the sulfate content was very low. This continuous variation in composition is in agreement with the previously proposed structure of this phase.