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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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.”
P. Savva, S. Chatzidakis, M. Varvayanni, A. Ikonomopoulos, N. Chrysanthopoulou, N. Catsaros, M. Antonopoulos-Domis
Nuclear Technology | Volume 188 | Number 3 | December 2014 | Pages 322-335
Technical Note | Fission Reactors | doi.org/10.13182/NT13-108
Articles are hosted by Taylor and Francis Online.
Research reactors are used for many applications: material testing; radioisotope production; beam-line applications for material research; nuclear transmutation doping; neutron activation analysis; neutron radiography experiments; fuel waste management; and other neutron and nuclear material related quantities, features, and research areas of interest. Each application requires enhanced neutron fluxes in a specific section of the energy spectrum; therefore, appropriate irradiation positions in the core or an appropriate configuration of the beam line need to be chosen. In several cases the required flux exceeds the maximum value that can be obtained in the existing irradiation positions of the operating reactor core, but the desired neutron flux amplification through the reactor power upgrade would require large-scale transformations, high costs, and long shutdown periods. With the creation of a flux trap at a central core position in the open pool Greek Research Reactor (GRR-1), a noticeable local increase of the thermal neutron flux was achieved, compared to the irradiation channels at peripheral core positions. In the present technical note, calculational and measurement results concerning the original core modification are presented, while the possibility of larger sample irradiation at higher thermal neutron flux in the GRR-1 is investigated. The presented results are based on deterministic and stochastic neutronic calculations with numerical models validated using measurements conducted for the original flux trap. The work is completed with a thorough thermal-hydraulic analysis to evaluate the impact of the proposed modifications to reactor operation. The study showed that the flux trap enlargement with complete removal of a central control fuel assembly increases the maximum thermal neutron flux by ∼41%, while further removal of the neighboring fuel assembly leads to an average flux increase of ∼45%, thus offering capabilities for extended reactor utilization such as additional isotope production.