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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 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.
A. M. Shahub, M. M. R. Williams
Nuclear Technology | Volume 86 | Number 1 | July 1989 | Pages 80-86
Technical Note | Nuclear Safety | doi.org/10.13182/NT89-A34286
Articles are hosted by Taylor and Francis Online.
The importance of Brownian and gravitational collision efficiencies in aerosol coagulation is examined through results from the AEROSIM computer code, which models the behavior of nuclear aerosol particles in a closed volume. Viscous, retarded London van der Waals and electrostatic forces are included in the NACE computer program for the calculation of collision efficiency. Results reveal that the minimum ratios of particle concentration with and without calculated collision efficiencies are 0.51 for Brownian coagulation plus sedimentation, 0.01 for gravitational coagulation plus sedimentation, and 0.08 when all the mechanisms are included.