The permeation behavior under oscillating-pressure conditions was studied. It was deduced from these results that the diffusivity could be described by:

D:     D (m2/s) = 5.08 x 10-7 exp[-39.6(kJ/mol)/RT]

H:     D (m2/s) = 6.60 x 10-7 exp[-40.4(kJ/mol)/RT]

Measurement of Permeation of Hydrogen Isotopes through Nickel by Oscillating Pressure Change. A.Tahara, Y.Hayashi: Journal of the Japan Institute of Metals, 1984, 48[12], 1152-6