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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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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INL’s new innovation incubator could link start-ups with an industry sponsor
Idaho National Laboratory is looking for a sponsor to invest $5 million–$10 million in a privately funded innovation incubator to support seed-stage start-ups working in nuclear energy, integrated energy systems, cybersecurity, or advanced materials. For their investment, the sponsor gets access to what INL calls “a turnkey source of cutting-edge American innovation.” Not only are technologies supported by the program “substantially de-risked” by going through technical review and development at a national laboratory, but the arrangement “adds credibility, goodwill, and visibility to the private sector sponsor’s investments,” according to INL.
Joonhong Ahn, Shinichi Nakayama
Nuclear Technology | Volume 97 | Number 3 | March 1992 | Pages 323-335
Technical Paper | Radioactive Waste Management | doi.org/10.13182/NT92-A34640
Articles are hosted by Taylor and Francis Online.
Numerical results are presented for an analysis of diffusion of237Np, a redox-sensitive radionuclide, in engineered barriers consisting of overpack and bentonite-filled buffer regions, with oxidation-reduction kinetics of neptunium with iron and dissolved oxygen. Steady-state distributions of Fe(II) and dissolved oxygen are first obtained by considering the oxidation reaction of Fe(II) with oxygen. Based on these profiles, the neptunium diffusion models for pH 6.5 and 9.0 are established. Analytical or finite element solutions are obtained for the corresponding mathematical problems. At pH 9.0, even if dissolved oxygen intrudes on the buffer region from the rock/buffer interface, the penetration of oxygen into the overpack region and to the surface of the waste solid can be avoided. Thus, less soluble, strongly sorbing Np(IV) is released from the waste solid. At pH 6.5, dissolved oxygen can reach the waste surface. Weakly sorbing, soluble Np(V) is released from the waste solid. Although the released Np(V) is reduced to Np(IV) by Fe(II) in the overpack region, the Np(IV) is quickly oxidized by Fe(III) and dissolved oxygen at the overpack-buffer interface. Neglecting the existence of dissolved oxygen and assuming that the repository is kept under a reducing environment so that only Np(IV) migrates might lead to quite an optimistic estimate of the neptunium release rate from the engineered barriers.
