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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
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.”
Joonhong Ahn, Shinichi Nakayama
Nuclear Technology | Volume 97 | Number 3 | March 1992 | Pages 323-335
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT92-A34640
Articles are hosted by Taylor and Francis Online.
Numerical results are presented for an analysis of diffusion of237Np, a redox-sensitive radionuclide, in engineered barriers consisting of overpack and bentonite-filled buffer regions, with oxidation-reduction kinetics of neptunium with iron and dissolved oxygen. Steady-state distributions of Fe(II) and dissolved oxygen are first obtained by considering the oxidation reaction of Fe(II) with oxygen. Based on these profiles, the neptunium diffusion models for pH 6.5 and 9.0 are established. Analytical or finite element solutions are obtained for the corresponding mathematical problems. At pH 9.0, even if dissolved oxygen intrudes on the buffer region from the rock/buffer interface, the penetration of oxygen into the overpack region and to the surface of the waste solid can be avoided. Thus, less soluble, strongly sorbing Np(IV) is released from the waste solid. At pH 6.5, dissolved oxygen can reach the waste surface. Weakly sorbing, soluble Np(V) is released from the waste solid. Although the released Np(V) is reduced to Np(IV) by Fe(II) in the overpack region, the Np(IV) is quickly oxidized by Fe(III) and dissolved oxygen at the overpack-buffer interface. Neglecting the existence of dissolved oxygen and assuming that the repository is kept under a reducing environment so that only Np(IV) migrates might lead to quite an optimistic estimate of the neptunium release rate from the engineered barriers.
