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Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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.”
Milos I. Atz, Massimiliano Fratoni
Nuclear Technology | Volume 210 | Number 5 | May 2024 | Pages 795-813
Research Article | doi.org/10.1080/00295450.2023.2246736
Articles are hosted by Taylor and Francis Online.
Nuclear fuel cycle advancements will result in new types of fissile material, including nuclear wastes, that require security and safeguards. Nuclear wastes may be more vulnerable for diversion by non-state actors, and chemical processing to recover fissile material is not an insurmountable challenge. Previous work has applied a figure of merit (FOM) to assess material attractiveness and security risks. This analysis applies the material attractiveness FOM to wastes produced by fuel cycles from the Fuel Cycle Evaluation and Screening (FCES) study. Two aspects of security risk are studied: (1) the time before the fissile material in the waste becomes attractive and (2) the number of waste packages required to obtain a critical mass of fissile material. Two fuel cycles are presented to highlight detailed results: (1) once-through use of low-enriched U in light water reactors (LWRs) and (2) continuous recycle of Pu in sodium fast reactors (SFRs). Increasing LWR used nuclear fuel (UNF) package loading increases the time to attractiveness, but the larger packages contain enough Pu for multiple critical masses. The high-level waste (HLW) from processing the SFR fuels has similar FOM behavior but longer time to attractiveness due to the concentration of fission products. More HLW packages are required to obtain a critical mass; that number can be further increased by increasing the separation efficiency. Extended to all FCES fuel cycles, the minimum time before attractiveness is generally lower for UNF than for HLW because radioactivity is concentrated in HLW. For nearly all fuel cycles that produce UNF, only one package is required to recover enough fissile material for a critical mass. Notably, some advanced fuel cycles produce HLW, of which only two packages need to be recovered to obtain a critical mass, even when the target fissile material is recycled. Going forward, an assessment of the security risks posed by fissile material in nuclear wastes will need to quantify the challenge posed by separations. Ultimately, the assessment could inform security and response measures; whether any of the observations might affect these measures could be an area for future work. Finally, future analysis could study whether different fuel cycle wastes are more attractive for use in radiological dispersal devices or radiological exposure devices.