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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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The Frisch-Peierls memorandum: A seminal document of nuclear history
The Manhattan Project is usually considered to have been initiated with Albert Einstein’s letter to President Franklin Roosevelt in October 1939. However, a lesser-known document that was just as impactful on wartime nuclear history was the so-called Frisch-Peierls memorandum. Prepared by two refugee physicists at the University of Birmingham in Britain in early 1940, this manuscript was the first technical description of nuclear weapons and their military, strategic, and ethical implications to reach high-level government officials on either side of the Atlantic. The memorandum triggered the initiation of the British wartime nuclear program, which later merged with the Manhattan Engineer District.
Mitsuru Kambe
Nuclear Technology | Volume 128 | Number 1 | October 1999 | Pages 12-24
Technical Paper | Fission Reactors | doi.org/10.13182/NT99-A3010
Articles are hosted by Taylor and Francis Online.
A 60-MW(electric) fast reactor concept, RAPID-A, without any control rods has been shown to achieve inherent safety and highly automated reactor operation and to provide reactivity control systems with maintenance-free and reliable performance over the plant design lifetime. RAPID-A is one of the variants of the refueling by all pins integrated design (RAPID), fast reactor concept, which enables quick and simplified refueling 2 months after reactor shutdown. In addition to the aforementioned advantages, unique challenges in reactivity control system design have been attempted in the RAPID-A concept. The design involves the following innovative reactivity control systems: lithium expansion modules for inherent reactivity feedback, lithium injection modules for inherent ultimate shutdown, and lithium release modules for automated reactor startup.