Pulsed-Neutron Measurements in Diphenyl at 24, 85, and 105°C

The diffusion parameters of diphenyl at 24, 85, and 105°C were investigated using a pulsed-neutron source. Particular emphasis was placed on reducing the effect of room-return background, a major source of error in experiments of this type. The data were analyzed by the usual three-parameter fit and in terms of the thermalization time constant. The results are in good agreement with a theoretical calculation and measurements using differential techniques but do not show a discontinuity of D₀ vs T in going from the solid to the liquid phase.