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 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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
Dec 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
January 2026
Nuclear Technology
December 2025
Fusion Science and Technology
November 2025
Latest News
What’s the most difficult question you’ve been asked as a maintenance instructor?
Blye Widmar
"Where are the prints?!"
This was the final question in an onslaught of verbal feedback, comments, and critiques I received from my students back in 2019. I had two years of instructor experience and was teaching a class that had been meticulously rehearsed in preparation for an accreditation visit. I knew the training material well and transferred that knowledge effectively enough for all the students to pass the class. As we wrapped up, I asked the students how they felt about my first big system-level class, and they did not hold back.
“Why was the exam from memory when we don’t work from memory in the plant?” “Why didn’t we refer to the vendor documents?” “Why didn’t we practice more on the mock-up?” And so on.
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.