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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
S. Moriyama, T. Fujii, H. Kimura, K. Anno, K. Yokokura, S. Shinozaki, M. Terakado, S. Hiranai
Fusion Science and Technology | Volume 42 | Number 2 | September-November 2002 | Pages 467-481
Technical Paper | doi.org/10.13182/FST02-A241
Articles are hosted by Taylor and Francis Online.
Research and developments on the ion cyclotron range of frequency (ICRF) heating system in the JT-60 upgrade (JT-60U) are presented. The developments and experiences on the operation of the ICRF heating system contribute to its upgrade and to future ICRF heating systems in ITER. The ICRF heating system for JT-60U started operation in January 1992. RF power up to 7 MW for 1.1 sec at 116 MHz has been coupled to a plasma as a result of the developments described in this paper. New high power tetrodes having pyrolitic graphite grids for higher dissipation of screen and control grids were tested in the ICRF amplifier, and 1.7 MW of the output power at 131 MHz for 5.4 seconds was achieved. This was the highest power level for fusion research above 110 MHz in 1990. A pair of phased loop antenna arrays (2 × 2) showed sufficiently high coupling resistance. To keep the impedance matching between the antenna and the transmission line, a frequency feedback control (FFC) system was developed, and its effectiveness was proved to couple high power RF continuously to the variable plasma. In ITER, enhancement of dielectric loss tangent of ceramics due to neutron irradiation will limit power injection capability of the antenna significantly. To solve this problem, an all-metal support (AMS) was developed in the JT-60U ICRF heating system as a substitute for a ceramic support of a central conductor of a coaxial antenna feeder in the ITER ICRF antenna.