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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
Work advances on X-energy’s TRISO fuel fabrication facility
Small modular reactor developer X-energy, together with its fuel-developing subsidiary TRISO-X, has selected Clark Construction Group to finish the building construction phase of its advanced nuclear fuel fabrication facility, known as TX-1, in Oak Ridge, Tenn. It will be the first of two Oak Ridge facilities built to manufacture the company’s TRISO fuel for use in its Xe-100 SMR. The initial deployment of the Xe-100 will be at Dow Chemical Company’s UCC Seadrift Operations manufacturing site on Texas’s Gulf Coast.
Robert J. Tuttle
Nuclear Science and Engineering | Volume 21 | Number 4 | April 1965 | Pages 451-462
Technical Paper | doi.org/10.13182/NSE65-A18789
Articles are hosted by Taylor and Francis Online.
The variation of neutron importance with energy and position has been investigated in a multiregion critical assembly having a series of test regions typical of slightly epithermal to fast power reactors. Values of neutron importance at the center of the test regions were measured using neutron sources and a reactivity oscillator. The variation of neutron importance with position was determined using neutron sources in conjunction with a dynamic reactivity-measurement technique. Analysis of data from similar beryllium- and carbon-moderated test regions indicates the significance of the Be(n, 2n) reaction. The neutron sources used in this study were Po-Be, Po-B11, Po-CaF2, Po-Li7, Mock Fission and Sb-Be. Published source spectra were used in the analysis of the data; the Mock-Fission-source spectrum was determined by gamma-ray spectroscopy. Relative yields of these sources were determined by calibration in a manganese sulfate bath.
