In this thesis, the use of the Fricke-gelatin dosimeter in NMR-based radiation dosimetry is investigated. The relationship between the proton spin-lattice relaxation rate and the absorbed dose for the Fricke-gelatin dosimeter is determined using pulsed NMR at 25 MHz. This relationship is used to calculate the NMR dose sensitivity. Practical considerations of Fricke-gelatin dosimetry, such as the spontaneous conversion of ferrous to ferric ions and the effects of oxygen and sodium chloride on the dose response, are determined. Sensitization of the dosimeter by bubbling with a nitrous oxide/oxygen gas mixture is investigated. The system is modelled assuming a multi-site fast exchange between water bound to gelatin, water bound to ions, and water in the bulk. Preliminary aspects of the model are investigated and compared with experimentally determined data. Finally, the utility of the dosimeter is demonstrated by magnetic resonance imaging a Fricke-gel irradiated with an $ sp{192}$Ir radioactive seed.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.68194 |
| Date | January 1994 |
| Creators | Keller, Brian Michael |
| Contributors | Schreiner, L. John (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Medical Radiation Physics.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001397517, proquestno: AAIMM94452, Theses scanned by UMI/ProQuest. |
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