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ANS Student Conference 2025
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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
Jorma Jokiniemi, Kimmo Koistinen, Taisto Raunemaa
Nuclear Technology | Volume 90 | Number 3 | June 1990 | Pages 394-407
Technical Paper | RELAP/MOD2 / Nuclear Safety | doi.org/10.13182/NT90-A34403
Articles are hosted by Taylor and Francis Online.
Hygroscopic aerosols were studied at 40° C at different relative humidity levels in a flow-type reactor chamber. The main interest was in growth of hygroscopic aerosols under higher humidity conditions. The time development of the aerosol in the 0.01- to 17-µm size range was determined using electrical aerosol analyzer and optical particle counter aerosol analyses. Low velocity and laminar flow were used to facilitate the comparison with theoretical considerations. Cesium hydroxide (CsOH) and sodium hydroxide (NaOH) were used as hygroscopic materials. Cesium is one of the most abundant species in core melt release, and NaOH is well known for its hygroscopic properties. The primary particles were produced by a constant output atomizer. The dry particle size, as volume median diameter (VMD), for CsOH was 1.8 µm. The observed airborne particle size after 2 min of travel was 6.3 µm, after 5 min 5.3 µm, and after 10 min 3.4 µm at saturated conditions. For dry NaOH aerosol, the measured initial VMD was 2.7 µm. At saturated conditions, the observed VMD was 6.7 µm after a 10-min travel. Theoretical calculations with the modified NAUA code showed that during travel through the chamber, the particle size change can be attributed to hygroscopic growth and sedimentation.