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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
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.”
J. R. L. de Ladonchamps, L. M. Grossman
Nuclear Science and Engineering | Volume 12 | Number 2 | February 1962 | Pages 238-242
Technical Paper | doi.org/10.13182/NSE62-A26063
Articles are hosted by Taylor and Francis Online.
The space energy distribution of neutrons diffusing in a source-free, nonabsorbing medium possessing a temperature gradient is obtained by solving the appropriate Boltzmann equation to a second order approximation using the expansion technique of Chapman and Enskog. The medium is assumed to possess a locally Maxwellian energy distribution and the neutron scattering is taken to be isotropic in the laboratory system of coordinates. It is found that the neutron current is increased in the direction of a negative temperature gradient and the “thermal diffusion” transport coefficient is evaluated as a function of the mass of the moderator nuclei. For the case of infinite mass nuclei, the results correspond to the kinetic theory model of a Knudsen gas in a binary Lorentzian gas mixture. An analysis of the results is carried out in the framework of the thermodynamic theory of coupled irreversible processes.
