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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Senate committee hears from energy secretary nominee Chris Wright
Chris Wright, president-elect Trump’s pick to lead the U.S. Department of Energy, spent hours today fielding questions from members of the U.S. Senate’s committee on Energy and Natural Resources.
During the hearing, Wright—who’s spent most of his career in fossil fuels—made comments in support of nuclear energy and efforts to expand domestic generation in the near future. Asked what actions he would take as energy secretary to improve the development and deployment of SMRs, Wright said: “It’s a big challenge, and I’m new to government, so I can’t list off the five levers I can pull. But (I’ve been in discussions) about how to make it easier to research, to invest, to build things. The DOE has land at some of its facilities that can be helpful in this regard.”
W. S. Yang, Y. Kim, R. N. Hill, T. A. Taiwo, H. S. Khalil
Nuclear Science and Engineering | Volume 146 | Number 3 | March 2004 | Pages 291-318
Technical Paper | doi.org/10.13182/NSE04-A2411
Articles are hosted by Taylor and Francis Online.
A systematic study on long-lived fission products (LLFPs) transmutation has been performed with the aim of devising an optimal strategy for their transmutation in critical or subcritical reactor systems and evaluating impacts on the geologic repository. First, 99Tc and 129I were confirmed to have highest transmutation priorities in terms of transmutability and long-term radiological risk reduction. Then, the transmutation potentials of thermal and fast systems for 99Tc and 129I were evaluated by considering a typical pressurized water reactor (PWR) core and a sodium-cooled accelerator transmutation of waste system. To determine the best transmutation capabilities, various target design and loading optimization studies were performed. It was found that both 99Tc and 129I can be stabilized (i.e., zero net production) in the same PWR core under current design constraints by mixing 99Tc with fuel and by loading CaI2 target pins mixed with ZrH2 in guide tubes, but the PWR option appears to have a limited applicability as a burner of legacy LLFP. In fast systems, loading of moderated LLFP target assemblies in the core periphery (reflector region) was found to be preferable from the viewpoint of neutron economy and safety. By a simultaneous loading of 99Tc and 129I target assemblies in the reflector region, the self-generated 99Tc and 129I as well as the amount produced by several PWR cores could be consumed at a cost of ~10% increased fuel inventory. Discharge burnups of ~29 and ~37% are achieved for 99Tc and 129I target assemblies with an ~5-yr irradiation period.Based on these results, the impacts of 99Tc and 129I transmutation on the Yucca mountain repository were assessed in terms of the dose rate. The current Yucca Mountain release evaluations do not indicate a compelling need to transmute 99Tc and 129I because the resulting dose rates fall well below current regulatory limits. However, elimination of the LLFP inventory could allow significant relaxation of the waste form and container performance criteria, with associated economic benefits. Therefore, some development of either specialized waste form or transmutation target for the LLFP is prudent, especially considering the potential accumulation of large LLFP inventory with sustained use of nuclear energy into the future.