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.
Division Spotlight
Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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!
Latest Magazine Issues
Jun 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
July 2025
Fusion Science and Technology
Latest News
Take steps on SNF and HLW disposal
Matt Bowen
With a new administration and Congress, it is time once again to ponder what will happen—if anything—on U.S. spent nuclear fuel and high-level waste management policy over the next few years. One element of the forthcoming discussion seems clear: The executive and legislative branches are eager to talk about recycling commercial SNF. Whatever the merits of doing so, it does not obviate the need for one or more facilities for disposal of remaining long-lived radionuclides. For that reason, making progress on U.S. disposal capabilities remains urgent, lest the associated radionuclide inventories simply be left for future generations to deal with.
In March, Rick Perry, who was secretary of energy during President Trump’s first administration, observed that during his tenure at the Department of Energy it became clear to him that any plan to move SNF “required some practical consent of the receiving state and local community.”1
K. Subba Rao, M. Srinivasan
Nuclear Technology | Volume 49 | Number 2 | July 1980 | Pages 315-320
Technical Note | Reactor | doi.org/10.13182/NT80-A32493
Articles are hosted by Taylor and Francis Online.
BeH2 could serve as an effective moderator in reducing critical masses in minimum critical mass systems on account of its (n,2n) reactivity bonus and the possibly higher hydrogen atomic density. A parametric study of the variation of keff and critical mass with BeH2 moderator density in the range of 600 to 1000 kg/m3 for the three main fissile nuclides of 235U, 233U, and 239Pu in small spherical thermal assemblies indicates that for 0.40-m-thick BeO-reflected spherical systems with BeH2 moderator of density ≥680 kg/m3 the critical masses are lower than with any other known moderator (such as H2O or CH2). With a moderator of crystalline BeH2 having a density of 780 kg/m3, critical masses are found to be lower than with CH2 by about 15%.
