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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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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.
Kostadin A. Dinov, Kazuo Kasahara
Nuclear Technology | Volume 115 | Number 1 | July 1996 | Pages 81-90
Technical Paper | Material | doi.org/10.13182/NT96-A35277
Articles are hosted by Taylor and Francis Online.
A theoretical approach is discussed that regards the kinetically determined pressurized water reactor (PWR) primary system as a set of thermodynamically defined metastable states that the related high-temperature aqueous system containing a combination of possible oxide phases (NixFe3−xO4, Fe3O4, and metallic nickel or NiO) and corresponding dissolution products may undergo under specified initial conditions. The study shows that stability zones of those metastable states, particularly M1 (NixFe3−xO4) and M3 [Ni(m) + NixFe3−xO4], cover practically the entire PWR operational range and depend on specific plant conditions and applied chemistry control. The thermodynamic analysis is predicated on the belief that defining the stability transition boundary between those states — found as a function of temperature, coolant pH, dissolved hydrogen (DH), and ferrite stoichiometry (x value) — is of primary importance for corrosion product behavior. Such a stability change influences both the particulate and ionic levels and the related activity transport and should be regarded as an important factor in optimizing PWR primary chemistry. The study offers an original approach to reassessing such important issues as thermodynamic data and the solubility of spinel oxides, the role of transport of particulates and soluble species, “optimum” pH and DH, and the chemistry effect on crud burst.
