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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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
Standards Program
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.
Mark L. Williams, R. Raharjo
Nuclear Science and Engineering | Volume 126 | Number 1 | May 1997 | Pages 19-34
Technical Paper | doi.org/10.13182/NSE97-2
Articles are hosted by Taylor and Francis Online.
A new method is developed to determine space-dependent, self-shielded cross sections for resonance nuclides with no overlapping resonances, contained in an arbitrarily shaped absorber body within some general lattice configuration. The theoretical basis for the method is discussed, and analytical expressions are presented for the space-dependent flux spectrum in the vicinity of an isolated resonance and for the space-dependent variation in the shielded resonance integral and multigroup cross section. The shielded cross-section expressions contain space-dependent, “weighted escape probabilities” that correspond to the weighted average of the energy-dependent escape probability over each energy group. The method is implemented in an assembly lattice physics code, and results are compared to those obtained with a highly accurate transport theory calculation that uses pointwise cross-section data. The method gives good agreement for the radial variation in the self-shielded cross section through a boiling water reactor fuel pellet.