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The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
A. H. Spano
Nuclear Science and Engineering | Volume 15 | Number 1 | January 1963 | Pages 37-51
Technical Paper | doi.org/10.13182/NSE63-A26262
Articles are hosted by Taylor and Francis Online.
Knowledge of the Doppler coefficient associated with the nonuniform temperature distribution conditions obtained in a reactor runaway is of importance to reactor safety considerations of low-enrichment oxide cores. Measurement of this dynamic coefficient has been made at Spert in an investigation of the kinetic behavior of a water-moderated, UO2-fuel-rod reactor, by means of self-limiting power excursion tests covering a range of initial asymptotic reactor periods from 31 sec to 3.2 msec. In the long-period region, reactor shutdown was provided both by various heat-transfer-dependent mechanisms effecting loss of moderator from the core and by Doppler broadening. In the short-period region below 7 msec, where the reactor period is small compared to the thermal time constant of the UO2 fuel rods and reactor shutdown is provided essentially by the Doppler reactivity alone, the data indicate Rc(tm) = −6.2 , where Rc(tm) and Em are, respectively, the compensated reactivity and energy (Mw-sec) at the time of peak power. An additional reactivity effect, positive in sign and resulting from systematic bowing of the fuel rods during the transient power burst, yielded a significant change in burst shape behavior. The fuel rod bowing effect was separated from other feedback effects by performing two series of tests, with and without mechanical constraints on the fuel rods. In the shortest period test, the maximum power was about 7500 Mw, the total energy released in the burst was about 110 Mw-sec, and the maximum pressure measured was less than 8 psi. No damage occurred as a consequence of this or any other test.