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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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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ANS designates Armour Research Foundation Reactor as Nuclear Historic Landmark
The American Nuclear Society presented the Illinois Institute of Technology with a plaque last week to officially designate the Armour Research Foundation Reactor a Nuclear Historic Landmark, following the Society’s decision to confer the status onto the reactor in September 2024.
R. E. Thoma, C. F. Weaver, H. bisley and H. A. Friedman
Nuclear Science and Engineering | Volume 19 | Number 4 | August 1964 | Pages 406-411
Technical Paper | doi.org/10.13182/NSE64-A18996
Articles are hosted by Taylor and Francis Online.
The equilibrium phase diagram of the condensed system NaF/BeF2/ThF4 is presented. Liquid/solid phase transitions were found in the temperature range from ∼300 to 1100 C. The phase diagram of the system is based on data obtained from thermal analysis and thermal-gradient-quenching experiments; phase identifications were made employing the polarizing light microscope and the x-ray diffractometer. Thirteen crystalline phases are precipitated as primary phases from molten NaF/BeF2/ThF4 solutions: 4NaF-ThF4, 7NaF·2ThF4, 2NaF·ThF4, 3NaF·2ThF4, α- and β -NaF·ThF4, NaF-2ThF4, 2NaF·BeF2, NaF·BeF2, NaF·BeF2, ·3ThF4, NaF, BeF2, and ThF4 solid solution. The character, location, and temperature of the fourteen invariant and singular points in the system were established. The ternary system is comprised of two subsystems, NaF/2NaF·ThF4/2NaF·BeF2 and 2NaF·ThF4/ThF4/BeF2/2NaF·BeF2, separated by the quasibinary section, 2NaF·BeF2/2NaF·ThF4. The lowest liquidus temperatures in the respective subsystems were found at the eutectics, 72NaF/22BeF2/6ThF4 (mole %), m.p. 509 C, and at 55NaF/43BeF2/2ThF4 (mole %), m.p. 320 C.
