“…The neutron-activa tion method described by J. J. Rowe in Page and others (1976) and by Haffty and others (1977), although more sensitive, is tedious and time consum ing. This method is also subject to fission product interference from 103Ru produced from U, unless sample pretreatment consisting of separating the Ru as the tetroxide, as described by Koda (1970), is employed.…”