Absorption spectra of irradiated films of polyvinyl chloride coated with perylene.
The visible and UV spectra γ-irradiated films of polyvinyl chloride doped or coated with perylene were recorded. These films were irradiated either under a vacuum, in N2 O or in NH3. In the case of...
Chemical dosimetry with trans-stilbene-doped polystyrene film.
Polystyrene film doped with trans-stilbene has been found useful as a chemical dosimeter for ionizing radiation. It is insensitive to photon energy changes and dose rate over the photon energy range from 4.7 MeV to 1.25 keV (mean) and for rates from 300 rads/sec to $0.75\times 10^{14}\ {\rm rads}/{\rm sec}$ . The mechanism for the dosimetry reaction, isomerization of trans- to cis-stilbene, is analogous to the mechanism proposed for radiolytic isomerization for fluid solution in benzene and toluene. The useful range of these films is from 2× 105 to 108 rads.
RADIATION DOSIMETRY WITH DYED CELLOPHANE.
Abstract Bleaching of dyed cellophane has been used a method of electron and γ-dosimetry in the Mrad range. We have investigated the response over a wider range of doses and compared the changes with those produced by α-irradiation. No consistent difference was found between gamma and electrons indicating that the dose rate is not an important factor. The results with α-radiation are more scattered and dependent on the penetration of alphas through the film; this can be estimated from the limiting degree of bleaching. Within these wider fluctuations there is no significant trend indicating an increased L.E.T. effect. The radiation sensitivity of the film is due to some form of transfer from the base cellophane to the dye, resulting in the bleaching of the latter with an overall G-value of about 0.17 to 0.34. It is concluded that the cellophane dyed film can be used for α-dosimetry within fairly wide limits of dose and accuracy.