Nuclear Engineering Commons^™

Novel Fission Track Detection For Identification And Characterization Of Special Nuclear Materials, Jonathan Allen Gill

Doctoral Dissertations

Fission track detection and analysis is used primarily in nuclear safeguards to identify special nuclear material. Identification of isotopic ratios is a crucial step in understanding the intended use of nuclear material and the nature of the materials production cycle. Unfortunately, this methodology uses etchable track detectors that require significant expertise and intensive labor to process.

This study developed a novel method using lithium fluoride (LiF) as a fluorescing nuclear track detector to conduct fission track analysis for isotopic prediction of uranium enrichment. Individual latent tracks produced by fission products were observed in LiF for the first time. These tracks …

Characterizing Local Order And Physical Properties Of Rare Earth Complex Oxides, Thomas Jacob Shamblin

Doctoral Dissertations

With more than 500 compositions, materials possessing the pyrochlore structure have a myriad of technological applications and physical phenomena. Three of the most noteworthy properties are the structure’s ability to resist amorphization making it a possible host matrix for spent nuclear fuel, its exotic magnetic properties arising from geometric frustration, and fast ionic conductivity for solid-oxide fuel cell applications. This work focuses on these three aspects of the pyrochlore’s many potential uses. Structural characterization revealed that pyrochlore-type oxides have a tendency to disorder from a high symmetry cubic structure to a lower symmetry orthorhombic arrangement in response to a variety …

Discovery And Development Of Rare Earth Activated Binary Metal Halide Scintillators For Next Generation Radiation Detectors, Kan Yang

Doctoral Dissertations

This work focuses on discovery and development of novel binary halide scintillation materials for radiation detection applications. A complete laboratory for raw materials handling, ampoule preparation, material rapid synthesis screening, single crystal growth, sample cutting, polishing and packaging of hygroscopic halide scintillation materials has been established. Ce³⁺ and Eu²⁺ activated scintillators in three binary systems: Alkali Halide – Rare Earth Halide (AX–REX₃), Alkali Halide – Alkaline Earth Halide (AX–AEX₂) and Alkalin Earth Halide – Rare Earth Halide (AEX₂–REX₃) were systematically studied. Candidates for new scintillation materials in the three systems …