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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.”
Graiciany de Paula Barros, Claubia Pereira, Maria A. F. Veloso, Renan Cunha, Antonella L. Costa
Fusion Science and Technology | Volume 61 | Number 1 | January 2012 | Pages 256-261
Fusion-Fission Hybrids and Transmutation | Proceedings of the Fifteenth International Conference on Emerging Nuclear Energy Systems | doi.org/10.13182/FST12-A13429
Articles are hosted by Taylor and Francis Online.
Accelerators Driven Systems (ADS) are an innovative type of nuclear system, which is useful for long-lived fission product transmutation and fuel regeneration. The ADS consist of a coupling of a sub-critical nuclear core reactor and a proton beam produced by a particle accelerator. These particles are injected into a target for neutrons production by spallation reactions. The neutrons are then used to maintain the fission chain in the subcritical core.The aim of this study is to investigate the nuclear fuel evolution of a lead cooled accelerator driven system used for energy production and high-level waste transmutation. The fuel studied is a mixture based upon 232Th-233U and Pu-MA extracted from PWR spent. The target is a lead spallation target and the core is filled with a hexagonal lattice. In order to reduce the negative reactivity caused by the presence of protactinium, moderator is not used.In this work is used the Monte Carlo code MCNPX 2.6.0, that presents the depletion/burnup capability, combining a ADS source and kcode-mode. The keff evolution, the neutron energy spectra in the core and the nuclear fuel depletion during the burnup are evaluated. Keywords: ADS, thorium, MCNPX.
