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2026 ANS Winter Conference & Expo
November 15–18, 2026
Phoenix, AZ|Arizona Grand Resort & Spa
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Fusion Science and Technology
August 2026
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Five companies, five bases: The Army’s Janus Program takes shape
Between the Nuclear Lifecycle Innovation Campuses and Nuclear Energy Launch Pad programs, August has already been a busy month for federal partnerships with the nuclear industry.
That trend continues: On Wednesday, the Department of the Army announced that it has selected five nuclear reactor developers—Antares Nuclear, BWXT Advanced Technologies, General Atomics Electromagnetic Systems, Radiant Industries, and Westinghouse Government Services—each paired with a different military installation, for its Janus Program.
This week, the nuclear community descended on Dallas, Texas, for the second annual Nuclear Energy Conference and Expo, the premier industry-focused nuclear conference cohosted by the American Nuclear Society and the Nuclear Energy Institute. Among the plenary panelists was Jeff Waksman, principal deputy assistant secretary of the Army for installations, energy, and environment. Waksman has been closely involved in the development of the Janus Program, and the morning before the program’s new selections were unveiled, he provided insights on its ultimate goals at NECX 2026.
Nicolae Bidica, Narcisa Ghimis, Bogdan Monea
Fusion Science and Technology | Volume 80 | Number 3 | April-May 2024 | Pages 504-519
Research Article | doi.org/10.1080/15361055.2024.2316477
Articles are hosted by Taylor and Francis Online.
Tritium permeation through structural materials of fusion reactors is an important issue from both safety and tritium self-sufficiency points of view. Mutual influences among hydrogen isotopes are also important in assessments of tritium permeation fluxes, and although some theoretical and experimental works have been carried out so far—which have all focused on steady-state permeation—their conclusions are insufficiently clear about how one isotope affects the permeation of another. This was motivation to further investigate this problem, both theoretical and experimental in a non-steady-state approach and also in the surface-limited regime (SLR) of permeation. After initial theoretical work, a dedicated experimental installation for gas-driven permeation experiments was designed and assembled. Then, initial experimental work was completed for testing monoisotope permeation of deuterium through a very thin (0.075-mm) nickel membrane in the temperature range of 473 to 773 K and for a driving pressure of deuterium gas in the range of 10−2 to 1 Pa. This work was done in preparation for subsequent multi-isotope experiments, with the proposed goal to observe how hydrogen affects the permeation of deuterium. The main objectives of the work were to confirm experimentally the achievement of the SLR of permeation for the selected conditions of testing; to determine experimentally the kinetic coefficients of surface transport for deuterium in nickel; and to test and validate the experimental setup, procedures, and methods used and their reliability to more stringent requirements of the multi-isotope experiments. Within this paper, the experimental setup and all the operating procedures used both in calibration operations and in permeation experiments are presented in detail, as well as their results. The obtained results confirmed that permeation occurred in the SLR in the tested range of pressure for each testing temperature. The surface-rate coefficients of dissociation and recombination were both determined experimentally. The values obtained for the dissociation coefficient were in very good agreement with other similar experimental data available in the literature. For the recombination coefficient, agreement was not quite satisfactory, but comparison could be made with values calculated based only on the dissociation and solubility coefficients, as data for these coefficients for the nickel-hydrogen system (determined directly from gas-driven permeation experiments) were not found in the literature. However, these results indicated good reliability of the installation, its calibration, and operating procedures in order to proceed to experimental testing of multi-isotope permeation.