Dose responses of scattered- and direct-X-ray-irradiated CR-39 and methylviologen-encapsulated silica nanocapsule-doped CR-39 and their mechanisms

Abstract

The photoexcited emissions of direct- and scattered-X-ray-irradiated CR-39 and methylviologen-encapsulated silica nanocapsule (MV2+@SiO2 NC)-doped CR-39 were observed, and they showed a dose response. The benzophenone radical was formed in a shallow trap in CR-39 upon X-ray irradiation from 10 to 30 Gy, and the fluorescence intensity increased with the dose. Methylviologen in SiO2 NCs competitively captured electrons generated by X-ray irradiation, and the captured electrons were reverse transferred to the shallow traps with time. A minimum dose rate of 300 µGy/s was observed between 1 and 5 Gy. Finally, a dose response of less than 2 mGy for scattered X-rays was obtained in this system.

Keywords

• Direct X-ray
• Scattered X-ray
• CR-39
• Photoexcited emission
• Dose response
• Silica nanocapsule