On the other hand, the increase of λd in the ∆ƒlong-z and Fcons, long-z curves showed more steeper time-temperature dependence. Since the 16 h-heated sample showed a similar λd value to the 142 h-settling sample, the shift factor aT,long and the activation energy ∆Elong of λd elongation are calculated to be aT, long =(142-24)/16 = 7.4 and Elong = 32 kJ mol -1 , which are obviously larger than ∆Eshort, aT, short and ∆Eη, aT, η. This suggests that the elongation rate of λd is determined by a different mechanism from the suppression of the short-range oscillatory component or the bulk viscous relaxation.