Abstract
As our basic work to establish precisely the reference isotopic abundance ratios of ruthenium, we examined carefully the isotopic abundance ratios of seven stable isotopes of ruthenium using its solution prepared by Aldrich Chemical Co., Inc., Milwaukee, WI, USA. Prior to our examination, Poths, Schmitt-Strecker and Begemann (1987) at Max-Planck-Institut für Chemie, Mainz, also determined precisely the corresponding ratios using Ru of Ventron-Alpha Co. Our 98Ru/99Ru ratio is about 11 ε higher than that reported by Poths et al., while our 104Ru/99Ru ratio is about 10 ε lower than that by them. As regards 96Ru, 100Ru, 101Ru and potentially 99Ru, there are little if any remarkable differences between us and them. The difference in 104Ru/99Ru is judged to reflect the interference from (88Sr16O)+ ion in their measurement. However, it is difficult to account for the difference in 98Ru/99Ru ratio. One cannot rule out the possibility that this has resulted from the difference in nuclear-decay contribution from 98Tc.
