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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
Gunzo Uchiyama, Shinobu Hotoku, Sachio Fujine, Mitsuru Maeda
Nuclear Technology | Volume 122 | Number 2 | May 1998 | Pages 222-227
Technical Paper | Enrichment | doi.org/10.13182/NT98-A2864
Articles are hosted by Taylor and Francis Online.
The kinetics of the reaction between Np(VI) and butyraldehyde isomers in nitric acid solution was studied to find flow-sheet conditions of the Np separation process from U and Pu. Iso-butyraldehyde was found to have a higher reduction rate than n-butyraldehyde. The former reduction rate at T = 283 to 323 K is described by the following equation:-d[Np(VI)]/dt= 6.0 × 106exp(-4.1 × 103/T)× [Np(VI)][iso-C3H7CHO]0[H+] (M/min).The latter reduction rate is described by the following equation:-d[Np(VI)]/dt= 4.2 × 104exp(-3.4 × 103/T)× [Np(VI)][n-C3H7CHO]0[H+] (M/min).
