Used Nuclear Fuel (UNF) contains transuranic (TRU) elements and numerous fission products as a result of the uranium fission process and neutron activation that occur in commercial light water power reactors. Recent environmental and nuclear proliferation concerns have spawned the development of advanced reprocessing techniques to close the nuclear fuel...
High-energy delayed γ-rays from photofission were demonstrated to be signatures for detection and identification of special nuclear materials. Such γ-rays were measured in between linac pulses using independent data acquisition systems. A list-mode system was developed to measure low-energy delayed γ-rays after irradiation. Photofission product yields of ²³⁸U and ²³⁹Pu...
In this work, three isomeric forms of N, N'-diethyl, N, N'-ditolyldipicolinamide (EtTDPA) were synthesized. The elements thorium through americium, which make up a significant portion of the actinides in used nuclear fuel (with the exception of curium), and two fission products, molybdenum and technetium, were tested for their ability to...
Renewed interest in fast nuclear reactors is creating a need for better understanding of fission gas bubble behavior in non-oxide fuels. Collisions between fission fragments and their subsequent cascades can knock fission gas atoms out of bubbles and back into the fuel lattice, resulting in a loss term for the...
The Boltzmann transport equation derived in the Self-Adjoint Angular Flux (SAAF) formulation is applied to simulate phonon transport. The neutron transport code Rattlesnake is leveraged in this fashion, slightly modi ed to accept input from variables consistent with phonon transport simulations. Several benchmark problems are modeled to assess the potential...
Pyroprocessing is an advanced technology for recycling used nuclear fuel. Pyrochemical processes encompass a wide range of chemical, physical, and electrochemical methods to partition fission products and other components from used nuclear fuel, which allows for the reuse of the actinides in nuclear fuel. This dissertation investigates two chemical systems...
The Advanced Test Reactor (ATR) is conducting
scoping studies for the conversion of its fuel from a
highly enriched uranium (HEU) composition to a low-enriched
uranium (LEU) composition, through the
Reduced Enrichment for Research and Test Reactors
Program, within the Global Threat Reduction Initiative.
These studies have considered a wide...
The most widely used and versatile medical radioisotope today is ⁹⁹[superscript]mTc. Roughly 30 million people depend on this radioisotope for diagnostic imaging procedures each year, and this demand is expected to grow. Although there are numerous ways of producing this isotope, the most common is from fission product 99Mo, which...
One of the most important components in the safety analysis of a nuclear reactor is its critical heat flux (CHF), as it can compromise the structural integrity of the clad and lead to the release of fission products into the primary coolant. Groeneveld et. al. has published a series of...
Effective separation of lanthanides (Ln) from the minor actinides (MA) is a crucial technical challenge to closing the nuclear fuel cycle. This separation is a necessary prerequisite to transmute long-lived isotopes of Am and Cm, which will allow a reduction of the repository volume, thermal load, and radiological toxicity of...