“…Therefore, during the fitting for the shortest lifetime, As the o-Ps component is relevant to the free-volume properties, and it is markedly sensitive to the microstructure changes, in this paper, our main attention is paid to the s 3 and I 3 . The lifetime parameters for the samples in the initial state, before thermal treatment, have already been reported [10][11][12]. The variations of o-Ps pick-off lifetime and its intensity for the investigated samples before and after thermal treatment are presented in Table 2.…”