ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
Apr 2026
Jan 2026
Latest Journal Issues
Nuclear Science and Engineering
May 2026
Nuclear Technology
February 2026
Fusion Science and Technology
Latest News
UIUC submits MMR construction permit application
The University of Illinois–Urbana-Champaign, in partnership with Nano Nuclear Energy, has submitted a construction permit application to the Nuclear Regulatory Commission for construction of a Kronos micro modular reactor (MMR). This is the first major step in the two-part 10 CFR Part 50 licensing process for the research and test reactor and is the culmination of years of technical refinement and regulatory alignment.
The team chose to engage with the NRC in a preapplication readiness assessment, providing the agency with draft versions of the majority of the CPA’s technical content for feedback, which is expected to ensure a high-quality application.
Kun Jie Yang, Yue-Lin Liu, Ning Liu, Peng Shao, Xu Zhang, Yuming Ma
Fusion Science and Technology | Volume 76 | Number 5 | July 2020 | Pages 616-631
Technical Paper | doi.org/10.1080/15361055.2020.1740556
Articles are hosted by Taylor and Francis Online.
We performed systematically first-principles calculations to investigate interstitial H diffusion/permeation of temperature dependence in tungsten (W). The interstitial H diffusion is primarily through two nearest-neighbor tetrahedral positions and its activation energy increases significantly with rising temperature. Phonon vibration plays a decisive role in the behavior of the H activation energy with rising temperature. The H permeation activation energy also depends strongly on the temperature since it is the sum of the formation energy and diffusion activation energy of H. Our calculated H diffusivity/permeability with the temperature agree quantitatively with the reliable experimental data within the error range in W. The vacancy-capturing effect can give a reasonable explanation of the discrepancy between simulation and experiment. Although the diffusion/permeation activation energy and the prefactor strongly depend on the temperature, the diffusivity/permeability of H still obeys quasi-Arrhenius behavior with rising temperature, which is attributed to the compensation effect between the activation energy and the prefactor, i.e., the increment of the prefactor compensates directly the modification of the diffusivity/permeability in the case of a variation in the activation energy with rising temperature.