Abstract
The thermal conductivities and the thermodiffusion ratios of 3He-4He systems up to 33% mixtures have been measured in vicinity of the lambda line to see how the dynamic critical phenomana is reflected on the kinetic coefficients. The thermal diffusivities deduced from these coefficients show the anomalies with the critical exponent of about 1/3, which verifies the dynamic scaling hypothesis in these system as well as in the pure system And, also, the diffusivities in He I, which correspond to the second sound damping coefficients in He II, show the same type of anomalies
These results verify the prediction given by the mode coupling theory, that the direct cancellation between two anomalously divergent terms causes the finiteness of the thermal conductivities in the mixtures.
On the other hand, the temperature dependence of the other diffusivities in He I, which correspond to the diffusion mode in He II, proved that the dynamic scaling hypothesis is not applied to this mode.
