本文介绍了离子流强度累计测定同位素比的方法。用热表面离子源测定了锂同位素丰度,在样品全耗尽过程中累计离子流强度。用该方法,同位素分馏效应对丰度比测量结果几乎没有影响。文中比较了累计法与常规法测量锂同位素丰度时分馏效应的差异。 This article describes a method for the integrated determination of isotope ratios by the intensity of ion fluxes. The abundances of lithium isotopes were measured using a hot surface ion source and the ion current intensities were accumulated during the sample depletion. Using this method, isotope fractionation effects have little effect on abundance ratio measurements. In this paper, the difference between the fractional distillation effect when measuring the abundance of lithium isotopes is compared between the cumulative method and the conventional method.