On the use of neodymium isotopes in burnup analysis of spent nuclear fuel

For burnup determination a simplification of the radiochemical sample treatment with the choice of such stable fission product isotopes not being disturbed by isobares of adjacent elements and offering good monitor qualities is presented. Neodymium isotopes 143Nd, 145Nd, and 146Nd have been used as monitor, isotopic spike and for correction due to natural neodymium contamination in mass spectrometric isotope dilution analysis. The formulas for calculating the burnup values have been derived and the sample treatment and measurement procedures are presented. (author)