| Abstract: | For the experimental determination of the H0 2/K ratio of the constants for prototype thermal diffusion columns from initial state mole fraction measurements there was a lack of sufficiently exact simple evaluation methods for polynary isotopic mixtures. The investigation of mole fraction changes at closed ends obtained by numerical integration of the corresponding system of second order partial differential equations resulted in a concept of approximation which allows to utilize approximative analytical solutions originally developed for binary isotopic mixtures. In the approximation the initial mole fractions are indirectly represented by the mean mass number of the initial mixture. Thus, the measured mole fraction changes can be attributed to the difference between the actual mass number of the components and the mean mass number of the enclosed mixture. By simple regression analysis a partial derivative can be obtained which can be attributed to the approximative analytical solutions for binary mixtures. |
