Project/Area Number |
06452419
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
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Allocation Type | Single-year Grants |
Research Field |
プラズマ理工学
|
Research Institution | Nagoya University |
Principal Investigator |
SUGAI Hideo Nagoya University, Faculty of Engineering, Professor, 工学部, 教授 (40005517)
|
Co-Investigator(Kenkyū-buntansha) |
SASAKI Kohichi Nagoya University, Faculty of Engineering, Assistant Professor, 工学部, 助手 (50235248)
NAKAMURA Keiji Nagoya University, Faculty of Engineering, Assistant Professor, 工学部, 助手 (20227888)
TOYODA Hirotaka Nagoya University, Faculty of Engineering, Associate Professor, 工学部, 講師 (70207653)
|
Project Period (FY) |
1994 – 1995
|
Project Status |
Completed (Fiscal Year 1995)
|
Budget Amount *help |
¥6,700,000 (Direct Cost: ¥6,700,000)
Fiscal Year 1995: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1994: ¥5,000,000 (Direct Cost: ¥5,000,000)
|
Keywords | first wall conditioning / boron coating / rithium coating / hydrogen recycling / oxygen gettering / impurity control / decaborane / ECR plasma |
Research Abstract |
Studies on stationary rectors with use of superconducting magnets have recently become more important. In this situation, conventional dc glow plasmas under no magnetic field is useless and, instead of them, magnetized plasmas such as ECR microwave plasmas have to be used. Furthemore, such techniques as lithium pellet injection will be promising for in situ wall conditioning without interrupting fusion plasmas. Most of this study was devoted to lithium coating and ECR-based boronization as follows : (1) Boron coating Two methods for new boronization in stationary reactors were proposed. One is injection of decaborane pellet injection and the other is boronization based on ECR microwave discharge under magnetic field. The basic experiment of ECR boronization showed a neutral radical deposition localized near the gas inlet and wider deposition of ionic radicals transported along magnetic lines of force, thus making a large vessel coating possible. (3) Lithium coating It was found for the first time that a lithium layr has a storong gettering effect on various molecules such as O_2, H_2O,CO and CH_4 while it absorbs a hydrogen atom per a lithium atom. Moreover, studies on the temperature dependence of hydrogen desorption and on hydrogen state in lithium layr. In future, lithium pellet injection could be a powerful tool of conditioning walls without interrupting a fusion plasma.
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