Radiation induced defects in graphite.

The Raman intensity ratio I/I for: (a) graphite-rich pencil rods irradiated using x-ray doses up to 20 Gy; (b) a restricted view of the I/I response for the same group of media, limited to x-ray doses of no more than 6 Gy; (c1 and c2) an extended group of graphite-rich media irradiated using Co gamma-rays; (d) a restricted view of the I/I response for a restricted group of the media shown in (c), with Co gamma-ray doses limited to no more than 20 Gy; (e) 2B graphite-rich pencil rods irradiated using 6 MeV electrons, and: (f) irradiation of a subset of the media by thermal (0.025 eV) neutrons. The fluctuation of I/I with dose for carbon-rich human hair of nominal diameter 60 μm is indicated by the dashed line in (c) and (d).

Graphite sheets in study of radiation dosimetry and associated investigations of damage.

Present work builds upon prior investigations concerning the novel use of graphite-rich polymer pencil-lead for passive radiation dosimetry. Working with photon-mediated interactions at levels of dose familiar in radiotherapy, exploratory investigations have now been made using graphite produced commercially in the form of 50 μm thick sheets. Focusing on the relationship between absorbed radiation energy and induced material changes, investigations have been made of thermo- and photoluminescence dose dependence, also of alterations in Raman spectroscopic features.

Studies of thermoluminescence kinetic parameters of polymer pencil lead graphite under photon exposures.

This study analysed thermoluminescence (TL) glow curves of the polymer pencil lead graphite (PPLG) due to its potential applications in radiation dosimetry. The TL glow curves provide information on the physical parameters of the defects participating in luminescence process. The glow curves for different diameters PPLG samples were obtained with varying temperature from 50 to 300 °C, at a fixed heating rate of 10 °Cs.

Raman and photoluminescence spectroscopy analysis of gamma irradiated human hair.

Preliminary study has been made of black human hair, carbon concentration of some 53%, a model in examining the potential of hair of the human head in retrospective and emergency biodosimetry applications, also offering effective atomic number near to that of water. The hair samples were exposed to [Formula: see text]Co gamma rays, delivering doses from 0 to 200 Gy. Structural alterations were observed, use being made of Raman and photoluminescence (PL) spectroscopy.