03/26/2024
By Zhiyong Gu
Title: Understanding Nuclear Materials and Radiochemical Processing using Neutron and Photon Spectroscopic
Techniques
Kristian Myhre
Radiochemist, R&D Staff
Oak Ridge National Laboratory
Abstract:
An in-depth understanding of how nuclear materials behave and radiochemical processes function is required for the advancement of nuclear energy, security, and medical technologies. Advanced spectroscopic techniques that use neutrons and photons to probe these materials and processes can provide a wealth of information. Neutrons offer a unique ability to penetrate high-Z materials, such as uranium, when x-rays would not. This ability allows neutrons to be used for imaging on various high-Z materials, including uranium fuel. Advanced neutron sources and detectors have enabled the development of spectroscopic neutron imaging techniques. These techniques can provide a wealth of 3D imaging, including isotopic or elemental content and crystallographic information. This presentation will discuss recent work at Oak Ridge National Laboratory on developing spectroscopic neutron imaging techniques, such as neutron energy resonance imaging, to study nuclear materials (e.g., tristructural-isotropic fuel materials). Additionally, photons offer a unique ability to be moved large distances through optical elements such as optical fibers. This ability allows many optical spectroscopy techniques to be used remotely, even within high radiation environments such as a hot cell. This presentation will also discuss efforts at the Radiochemical Engineering Development Center to stand up various optical spectroscopic techniques to monitor radiochemical processes in high-radiation environments.
Biography:
Kristian Myhre has been a research scientist at ORNL since 2016. He recently returned to research at ORNL after spending two years at the Department of Energy within the Office of Isotope R&D and Production as a technical advisor. His current focus is on improving radioisotope manufacturing technologies through innovative science and engineering R&D. He originally came to ORNL as a graduate student in 2013 through the joint ORNL and the University of Tennessee Bredesen Center’s Energy Science and Engineering Ph.D. program. Myhre’s dissertation research focused on the development of a new f-element separation technique utilizing solid electrolytes and molten salts. Myhre was first introduced to nuclear science and engineering through an undergraduate research assistant position at the University of Washington Medical Center’s Radiation Oncology Research Laboratory in Seattle, Washington.