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Deep Fission raises $30M in financing
Since the Department of Energy kicked off a 10-company race with its Nuclear Reactor Pilot Program to bring test reactors on line by July 4, 2026, the industry has been waiting for new headlines proclaiming progress. Aalo Atomics broke ahead of the pack first by announcing last week that it had broken ground on its 50-MWe Aalo-X at Idaho National Laboratory.
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.
