Determination of traces of boron in heat-resisting alloy standards by isotope dilution mass spectrometry

Traces (0.6∼130ppm) of boron in heat-resisting alloy standards of J AERI(Japan Atomic Energy Research Institute)and of NBS(National Bureau of Standards, U. S.)were determined by isotope dilution mass spectrometry which involved addition of 95% enriched boron-10 as the spike and isolation of boron from acid solution of samples by methyl borate distillation. The tantalum ribbon single filament technique was used for isotopic analysis of boron. Except for one JAERI standard, the results obtained by isotope dilution gave a relative standard deviation of less than 3%. Determination of boron in boron-added water samples, fly ash standard NBS 1633 and geochemical rock standards JG-1 and JB-1 was also carried out for comparison.