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Division Spotlight
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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ANS 2025 election is open
The American Nuclear Society election is now open. Members can vote for the Society’s next vice president/president-elect and treasurer as well as six board members (four U.S. directors, one non-U.S. director, and one student director). Completed ballots must be submitted by 1:00 p.m. (EDT) on Tuesday, April 15, 2025.
G. Klotzkin, R. F. Valentine, C. A. Flanagan, J. C. Stachew
Nuclear Science and Engineering | Volume 44 | Number 3 | June 1971 | Pages 413-422
Technical Paper | doi.org/10.13182/NSE71-A20172
Articles are hosted by Taylor and Francis Online.
A series of experiments performed at the High Temperature Test Facility of the Bettis Atomic Power Laboratory indicated that placing lead in the water-reflector region of a water-moderated thermal reactor causes the reactivity of the core to increase. Two-dimensional diffusion theory calculations of the above-mentioned experiments also predicted this, but undercalculated the Δk/k effect of 6 in. of lead by 25%. In addition, two-dimensional diffusion theory and Monte Carlo calculations were used to analyze the reactivity effect of a lead shipping container surrounding a Seed 2 cluster from Shippingport Core 2. All the calculations revealed that the presence of lead in the reflector region of a water-moderated core causes the reactivity of the core to be significantly higher than a core with a pure-water reflector.
