title: Simple radiochemical neutron-activation method for the determination of uranium in ultramafic rocks.
abstract: A radiochemical neutron-activation method for the determination of trace concentrations of uranium in rocks is described. The method is based on separation of 23.5-min (239)U after alkaline fusion by extraction with tri-n-butyl phosphate from moderately concentrated nitric acid, followed by measurement of the 74-keV gamma-ray with a Ge(Li) detector. The limit of detection is 0.2 ng of U under the present conditions, and the precision at the 0.005 ppm level is about 10%. The method is especially useful for determination of uranium in ultramafic rocks.
authors.affiliation: Institutt for Atomenergi, Isotope Laboratories, Kjeller, Norway.
authors.forename: E
authors.initials: E
authors.lastname: Steinnes