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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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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.”
P. Mohanakrishnan, H. C. Huria
Nuclear Science and Engineering | Volume 68 | Number 2 | November 1978 | Pages 220-226
Technical Note | doi.org/10.13182/NSE78-A27294
Articles are hosted by Taylor and Francis Online.
A theoretical analysis of the reactivities of experimentally measured uniform light-water-moderated and -reflected PuO2 in UO2 lattices and Pu(NO3)4 solutions is presented here. The mixed-oxide single-rod lattices are homogenized by the use of multigroup integral transport theory, and diffusion theory is used for the cylindrical core calculations. The cross sections are derived from the WIMS library. The homogeneous spherical Pu(NO3)4 solutions are analyzed by discrete-ordinates transport theory. Due to the small size of these assemblies, it is necessary that one-dimensional core calculations also be performed with a cross-section energy-group structure that can accurately represent neutron slowing down and thermalization at the core-reflector interface. Due to the uncertainty present in the Battelle Northwest Laboratories analyses of the mixed-oxide lattices, the agreement of our predictions for these lattices with measurement is considered to be more satisfactory. Our reactivity predictions agree generally within +0.6% of measurements for the mixed-oxide lattices and within 1% for the solution systems.
