Abstract
The experimental thermal diffusion factors αT of He4–Ar40 and Ne20–Xe132 gas mixtures at different compositions of the lighter components and an isotopic natural mixture of Ne20–Ne22 are estimated at the mean temperature \barT=340 K by the column calibration factor method from the available values of ln qe(qe being the equilibrium separation factor) for those mixtures at different pressures in atmosphere for each composition, measured by J. M. Saviron et al. in a thermal diffusion column with the column calibration factor Fs=3.946, the value (at \barT=340 K) derived from the formula Fs=68.94796−0.3174514 \barT+3.71383×10−4T2 as obtained by S. Acharyya et al. It is shown that the experimental αT’s, thus estimated with the help of Fs and ln qmax, agree excellently with those due to the existing methods using molecular models as well as with those due to Slieher’s model-independent method, so far as their magnitudes and the trends of their variation with the mole fraction of the lighter components are concerned. This suggests that the present method is a unique one which can safely be used to study the composition dependence of αT in both the isotopic and nonisotopic cases.
