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The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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.”
Kåre Hannerz, Lars Nilsson, Tor Pedersen, Christen Pind
Nuclear Technology | Volume 91 | Number 1 | July 1990 | Pages 81-88
Technical Paper | Safety of Next Generation Power Reactor / Nuclear Safety | doi.org/10.13182/NT90-A34443
Articles are hosted by Taylor and Francis Online.
The process inherent ultimate safety (PIUS) reactor is a 600-MW(electric) pressurized water reactor based on a concept developed and verified at ABB Atom during the last 10 years. It is designed to eliminate any possibility of a core degradation accident. Its basic design features a core that is openly connected, in a natural-circulation circuit, to a large pool of heavily borated water. This pool is kept in place by a prestressed concrete pressure vessel provided with redundant leakage barriers. The coolant pumps are operated so that there is hydraulic balance in the openings between the primary coolant loop and the pool. Therefore, the hot, low-boron primary loop water is kept separated from the pool water in spite of the always open natural-circulation path. In severe transients, such as loss of feedwater, this balance is affected, and pool water ingress occurs. Reactor shutdown and long-term residual heat removal are ensured without monitoring and intervention. Thus, safety is independent of potentially failure-prone devices and cannot be jeopardized by mistakes or malicious human acts. During normal operation, boron ingress to the primary loop due to turbulent diffusion can be kept at an adequately low level, as shown by a series of investigations and experiments. In transients the thermally stratified layer that separates hot primary coolant from cold high-boron pool water moves vertically. Large movements result in boron ingress and operational disturbances. These movements can be reliably calculated by computer simulations, as confirmed by test loop operation. Simulations and tests have shown that PIUS can survive even a grid voltage disturbance, implying loss-of-coolant pump power supply for >0.5 s, without boron ingress to the primary loop. (This severe operational transient is a Scandinavian requirement.) Hence, the risk that PIUS will experience spurious shutdowns due to the special arrangement for prevention of core degradation accidents is very small. The arrangement instead provides for plant simplification because of fewer safety systems and improved operator comprehension. PIUS should become a user friendly plant that can be run with high availability and for a long plant life.