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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.
Bau-Shei Pei, Ge-Ping Yu, Guei-Ching Lin, Yin-Pang Ma
Nuclear Technology | Volume 90 | Number 1 | April 1990 | Pages 49-62
Technical Paper | Nuclear Safety | doi.org/10.13182/NT90-A34385
Articles are hosted by Taylor and Francis Online.
Due to the potential threat of reactor coolant system (RCS) overpressurization, loss-of-normal-feed-water (LONF) transients without reactor trip have received special attention in the analysis of pressurized water reactor (PWR) anticipated transients without trip (ATWT). The U.S. Nuclear Regulatory Commission requires every PWR to be equipped with an ATWT mitigation system actuation circuitry (AMSAC) so that the turbine will be tripped and auxiliary feedwater (AFW) added when an LONF transient occurs. An AMSAC design proposed by Westinghouse Electric Corporation will be installed in both units of the Maanshan Nuclear Power Station (MNPS) to deal with ATWTs under LONF transient conditions. A best-estimate transient analysis performed with the RETRAN-02/MOD3 code is used to assess the safety function of the actuation circuitry designed for MNPS. Analytical results show that the peak RCS pressure will not exceed the 22.16-MPa safety limit if the moderator temperature coefficient is sufficiently negative and the actuation circuitry functions normally. Effects of the moderator temperature coefficient, the Doppler coefficient, pressurizer power-operated relief valves, effective time of the AFW system, the steam dump system, and the automatic control rod system are discussed.
