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
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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
Oct 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
November 2025
Nuclear Technology
Fusion Science and Technology
Latest News
Japan gets new U for enrichment as global power and fuel plans grow
President Trump is in Japan today, with a visit with new Prime Minister Sanae Takaichi on the agenda. Takaichi, who took office just last week as Japan’s first female prime minister, has already spoken in favor of nuclear energy and of accelerating the restart of Japan’s long-shuttered power reactors, as Reuters and others have reported. Much of the uranium to power those reactors will be enriched at Japan’s lone enrichment facility—part of Japan Nuclear Fuel Ltd.’s Rokkasho fuel complex—which accepted its first delivery of fresh uranium hexafluoride (UF₆) in 11 years earlier this month.
Mitsuru Kambe, Masaki Uotani
Nuclear Technology | Volume 122 | Number 2 | May 1998 | Pages 179-195
Technical Paper | Reactor Safety | doi.org/10.13182/NT98-A2861
Articles are hosted by Taylor and Francis Online.
To enhance the inherent safety of the fast breeder reactor (FBR), unique attempts are being made in reactivity control systems design to achieve maintenance-free and reliable performance at the Central Research Institute of the Electric Power Industry. The design involves the lithium expansion module (LEM) for inherent reactivity feedback and the lithium injection module (LIM) for inherent ultimate shutdown. Reactor physics calculation revealed the reactivity worth of LEM and LIM in a 60-MW(electric), metal-fueled FBR and a 1000-MW(electric) mixed-oxide-fueled FBR. The system dynamics analyses revealed that LEM and LIM are effective to avoid sodium boiling in unprotected transient overpower and unprotected loss-of-flow transients. Reliability, maintainability, and real-time monitoring for LEM and LIM are also discussed.
