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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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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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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TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Tsutomu Sakurai, Akira Takahashi, Niro Ishikawa, Yoshihide Komaki
Nuclear Technology | Volume 83 | Number 1 | October 1988 | Pages 24-30
Technical Paper | Fuel Cycle | doi.org/10.13182/NT88-A34172
Articles are hosted by Taylor and Francis Online.
The composition of NOx generated in the dissolution of UO2 has been described in different ways by earlier authors. Finding a way to determine the NOx composition in the dissolution included experiments concerning the reactions of NO and NO2 with 3 to 6 M HNO3. The following conclusions have been obtained for the dissolution: (a) of the NOx, NO is the direct product of the dissolution [3UO2 + 8HNO3 → 3UO2(NO3)2 + 2NO + 4H2O]; (b) part of the NO is converted quickly to NO2 by the second reaction, i.e., NO + 2HNO3→ 3NO2 + H2O (the equilibrium constant of this reaction determines the NOx composition); (c) the dissolution is therefore expressible as 3UO2 + 4(2 + x)HNO3→3UO2(NO3)2 + 2(1 — x)NO + 6xNO2 + 2(2 + x)H2O, (0 < × < 1) (some values of the × were obtained); (d) the amount of NO2 in the NOx is considerably smaller than that reported by earlier authors, e.g., 25% for 6.7 MHNO3 at 101°C; (e) UO2(NO3)2 coexisting in the solution tends to increase the NO component in the NOx.
