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60 Years of U: Perspectives on resources, demand, and the evolving role of nuclear energy
Recent years have seen growing global interest in nuclear energy and rising confidence in the sector. For the first time since the early 2000s, there is renewed optimism about the industry’s future. This change is driven by several major factors: geopolitical developments that highlight the need for secure energy supplies, a stronger focus on resilient energy systems, national commitments to decarbonization, and rising demand for clean and reliable electricity.
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.
