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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.
Riyadh M. Motny, Michael E. Woods, Supathorn Phongikaroon
Nuclear Technology | Volume 206 | Number 12 | December 2020 | Pages 1932-1944
Technical Paper | doi.org/10.1080/00295450.2020.1730672
Articles are hosted by Taylor and Francis Online.
The leaching behavior of cerium and cesium from different mixtures of rapid setting cement (RSC) with deionized water (DIW) and artificial seawater (ASW) under both dynamic and static leach conditions was investigated according to the method in American National Standard ANSI/ANS-16.1-2003. The leachate solution was collected, diluted with HNO3, and analyzed using inductively coupled plasma–mass spectrometry after leaching periods of 2, 7, and 24 h and 2, 3, 4, 5, 14, 28, 43, and 90 days. Two models [the first-order reaction model (FRM) and the diffusion model (DM)] and their combination [the first-order reaction/diffusion model (FRDM)] were fitted to assess the leaching parameters and identify the type of immobilized radionuclides in the RSC matrix. The result indicated that leaching of 140Ce and 133Cs from the RSC matrices with DIW and ASW under both dynamic and static leach conditions was less than 20% and suggested that the leaching behavior of 140Ce and 133Cs approximated that of a semi-infinite medium. The leaching phenomena of 140Ce and 133Cs could not be fully represented with a single model (the FRM and the DM), and the FRDM was best fitted to these experimental data sets. Overall, the average leachability index L values for 140Ce and 133Cs were greater than the minimum limit indicating their acceptance for disposal recommended by the International Atomic Energy Agency. It could also be stated that RSC with DIW or ASW had a potential for immobilizing radioactive materials.
