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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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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.”
William E. Kastenberg
Nuclear Science and Engineering | Volume 37 | Number 1 | July 1969 | Pages 19-29
Technical Paper | doi.org/10.13182/NSE69-A20895
Articles are hosted by Taylor and Francis Online.
A general formalism for the determination of stability criteria by the method of comparison functions is derived for nuclear reactors whose system dynamics are governed by a coupled set of space-dependent nonlinear differential equations. The results obtained are applicable to the nonlinear multigroup diffusion equations with temperature feedback. A stability criterion for the nontrivial equilibrium state is presented in a theorem. In addition, two corollaries are presented for the particular cases of negative feedback. The criteria so obtained represent a measure of the “dissipative” forces as estimated by the eigenvalues of the linearized problem vs a measure of the “disruptive” forces caused by the feedback. If the net effect is dissipative then the system is asymptotically stable in the sense of Lyapunov. Two examples are presented to illustrate the formalism and use of the criteria. In the second example, a stability criteria for two-group theory with linear temperature feedback is derived directly from the equations of motion by this method.
