Skip to Main content Skip to Navigation
Theses

Développement de la spectroscopie de résonance paramagnétique électronique pour la dosimétrie d'accident radiologique sur les ongles des victimes

Abstract : The purpose of this work is to assist in the management of emergency situations following accidental exposition to ionizing radiations. The earlier absorbed doses are quantified following exposure, the more efficient the medical team will be able to handle and treat the victims. In most of radiological accidents, irradiation is localized and especially to the hands. Up to now, no techniques exist to estimate these doses with sufficient accuracy. IRSN is implementing a dosimetry technique based on the quantification of radiation induced free radicals using Electron Paramagnetic Resonance (EPR) spectroscopy in fragments human nails. However, the analysis of irradiated nails by EPR spectroscopy remains extremely complicated. A first step was to characterize the nature of radicals at the origin of the endogenous and radio-induced signals and to study their physicochemical properties. We also study the variability of these signals, and we identified a stable UV-induced signal that definitely contributes to the endogenous signal. Two approaches to measure low doses have been proposed: one is based on the behavior of radiation-induced signals with the microwave radiation power; the other is based on the selective regrowth of the radio-induced signal after its total elimination by means of chemical treatment. We have also raised the issue of spectral analyses that is operator-dependent. To avoid manual adjustments, we proposed a uniform EPR data processing approach. Traditional EPR procedures have been vastly improved through simple, repeatable and automatic functional processing of EPR spectra.
Complete list of metadatas

Cited literature [184 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02481127
Contributor : Abes Star :  Contact
Submitted on : Monday, February 17, 2020 - 11:52:42 AM
Last modification on : Friday, October 23, 2020 - 4:45:38 PM
Long-term archiving on: : Monday, May 18, 2020 - 3:05:55 PM

File

TKATCHENKO_Nicolas_these_2018....
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02481127, version 1

Citation

Nicolas Tkatchenko. Développement de la spectroscopie de résonance paramagnétique électronique pour la dosimétrie d'accident radiologique sur les ongles des victimes. Physique [physics]. Sorbonne Université, 2018. Français. ⟨NNT : 2018SORUS231⟩. ⟨tel-02481127⟩

Share

Metrics

Record views

90

Files downloads

336