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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
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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.”
K. Toi, F. Watanabe, S. Ohdachi, S. Morita, X. Gao, K. Narihara, S. Sakakibara, K. Tanaka, T. Tokuzawa, H. Urano, A. Weller, I. Yamada, L. Yan, LHD Experiment Group
Fusion Science and Technology | Volume 58 | Number 1 | July-August 2010 | Pages 61-69
Chapter 3. Confinement and Transport | Special Issue on Large Helical Device (LHD) | doi.org/10.13182/FST10-A10794
Articles are hosted by Taylor and Francis Online.
The L-H transition was observed in a unique helical divertor configuration where the core plasma is surrounded by ergodic layer, exhibiting rapid increase in edge electron density with sudden depression of H emission. Just after the transition, edge transport barrier (ETB) is formed at the plasma edge in the magnetic hill region, developing a steep density gradient. ETB region extends in ergodic layer beyond the last closed flux surface defined by the vacuum field. The transition occurs in relatively high beta plasmas when neutral beam absorbed power (Pabs) exceeds one to three times the ITER H-mode power threshold. Improvement of energy confinement time is modest (<1.1) for the ISS95 international stellarator scaling, whereas the particle confinement is clearly improved. The ETB width tends to increase with the increase in the toroidal beta at the ETB shoulder. ETB formation leads to destabilization of edge magnetohydrodynamic (MHD) modes with m/n = 2/3 or 1/2 (m and n being the poloidal and toroidal mode numbers) in ETB region of the inward-shifted configurations. Edge-localized modes (ELMs) are excited by these edge MHD modes through nonlinear evolution. Sometimes in outward-shifted plasmas, edge MHD modes are clearly suppressed in the H-phase and lead to an ELM-free H-mode. When large m/n = 1/1 resonant magnetic perturbations are applied to neutral beam injection-heated plasmas, the transition takes place at lower line-averaged electron density having the modest increase in electron temperature and small-amplitude ELMs.