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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.
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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.”
A. Boeuf, G. Casini, E. Macke, L. T. Papay, S. Tassan
Nuclear Science and Engineering | Volume 52 | Number 3 | November 1973 | Pages 360-381
Technical Paper | doi.org/10.13182/NSE73-A19483
Articles are hosted by Taylor and Francis Online.
The reactivity worths of synthetic plutonium-uranium clustered fuel elements in a heavy-water-moderated assembly have been experimentally determined using the reactor oscillation method. Several test-fuel compositions have been investigated, representing varying degrees of fucl burnup and burnup distributions; two uranium samples with different U enrichment have been used as standard. The technique selected was aimed to establish “clean” experimental conditions, in order to effectively simplify the analysis of the results. Basically, the technique involved oscillating, according to a square-wave pattern, a 6-m-long fuel element containing a 50-cm-high test section with the fuel composition to be investigated the corresponding neutron density modulation was interpreted in terms of a Fourier analysis. The results of the experiment form a consistent set of data that can be used as test values for refined reactor burnup calculation codes. The overall experimental error, typically ±0.015 pcm (1 pcm = 10-5 Δkeff/keff). is considered remarkably low in view of the massive experimental setup required. A method for the theoretical analysis of the measured reactivity worths is presented. A multigroup perturbation transport calculation in one dimension (S4 approximation) has been developed to account for the radial environmental conditions. The axial effects have been evaluated with a two-dimensional transport calculation. The group cross-section data used in the analysis were basically taken from the GAM-II and GATHER-II libraries. Using the same basic one-dimensional code with an appropriately adjusted input parameter, infinite lattice multiplication factors have also been calculated from he experimental reactivity results. These results are compared to the values of k∞ obtained from null-reactivity measurements of identical clusters which were performed in association with the Comitato Nazionale Energia Nucleare, Italy, in RB-1 Reactor in Bologna. The agreement between the two sets of results is satisfactory.
