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M. Mujahid, P. Singh, D. S. Srivastava, S. Gupta, D. K. Avasthi and D. Kanjilal, “Study of Chain Scission versus Crosslinking in MeV Ion-Irradiated Polycarbonate Using Dielectric Constant Measurements and UV Spectroscopy,” Radiation Measurements, Vol. 38, No. 1-6, 2004, pp. 197-203.

has been cited by the following article:

• TITLE: Microstructural Investigation of PM-355 Nuclear Track Detector Subjected to Low-Dose Gamma Irradiation: A Positron Annihilation Lifetime Study

  AUTHORS: Emad Hassan Aly

  KEYWORDS: Positron Annihilation Lifetime; Nuclear Track Detector; TEM; Gamma Dose; TGA

  JOURNAL NAME: Materials Sciences and Applications, Vol.4 No.10, October 17, 2013

  ABSTRACT: Samples of the PM-355 polymeric solid state nuclear track detector were exposed to low gamma absorbed doses from 1 kGy (0.1 Mrad) up to 9 kGy (0.9 Mrad). Positron annihilation lifetime (PAL) in conjunction with transmission electron microscopy (TEM) and Thermo-gravimetric analysis (TGA) were performed on irradiated and pristine samples at room temperature. The observed lifetime spectra were resolved into three components where the ortho-positronium (o-Ps) lifetime component was associated with the pick-off annihilation of positronium trapped by the free volume. PAL studies of irradiated PM-355 samples showed that ortho-positronium (o-Ps) lifetime increases with an increase in dose up to 4 kGy and decreases at higher doses. In contrast, the intensity of the o-Ps component, I3, decreases with the dose up to about 2 kGy, followed by a much smooth decrease up to 7 kGy, and then it levels off. TGA analysis indicated that the PM-355 detector decomposed in one main breakdown stage. These results are discussed on the basis of chemical and physical changes occurring at the microscopic level in the PM-355 due to irradiation. Crosslinking dominates for doses between 1 and 4 kGy, while the degradation mechanism (Chain scission) prevails for doses up to 9 kGy.