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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Latest News
Steam is a sign of cooling system function . . . at ITER
Steam from one of ITER’s ten induced-draft cooling cells offers visual confirmation of a successful cooling system test, the ITER organization announced April 30. ITER’s cooling system features 60 kilometers of piping with pumps, filters, and heat exchangers that can pull water through at up to 14 cubic meters per second. Once fully operational, two cooling loops—one to remove the heat generated by the plasma in the ITER tokamak and one for its supporting infrastructure—will be capable of extracting up to 1,200 MW of heat.
Nathan Andrews, Koroush Shirvan, Edward E. Pilat, Mujid S. Kazimi
Nuclear Technology | Volume 194 | Number 2 | May 2016 | Pages 204-216
Technical Paper | doi.org/10.13182/NT15-41
Articles are hosted by Taylor and Francis Online.
A comparison of burning weapons-grade plutonium in a standard pressurized water reactor (PWR) using thoria or urania as a fuel matrix has been performed. Two cladding options were considered: a silicon carbide (SiC) matrix of 0.76-mm thickness and Zircaloy of 0.57-mm thickness. As expected, in terms of percentage and total plutonium mass burned, there was a large benefit in using thoria as a matrix compared to urania. Additionally, a smaller amount of plutonium is required in a core when SiC is the cladding because of lower neutron absorption in SiC. The thorium system was also better from a plutonium-burning viewpoint. It resulted in less weapons-useable U and Pu at discharge and more burned over an assembly’s lifetime. At discharge, the fuel was shown to have lower multiples of minimum amounts needed for weapons, even when 233U breeding was taken into account. Thoria-plutonia fuel has different kinetic characteristics from urania-plutonia or enriched urania fuel, so a limited safety comparison of such fuels was made for two reactivity insertion accidents: (1) the highest worth rod ejection and (2) main-steam-line break (MSLB). The accident analyses were performed at both beginning and end of cycle. While the control rod worths are higher in the simulated thoria-plutonia and urania-plutonia cores than in conventional urania-loaded cores, the enthalpy added during the accident was lower than current safety limits for conventional cores. During the MSLB accident, all cases showed acceptable behavior, indicating that the less negative moderator temperature coefficients of thoria-plutonia and urania-plutonia fuel were not limiting.