東京工業大学 · Physics and Astronomy
테규타 요코야마 교수의 연구실은 플라즈마 물리학과 표면화학을 기반으로 한 고체 표면 상의 분자 상호작용 및 플라즈마 안정화 메커니즘을 연구합니다. 특히 대기압에서의 글로우 discharge 안정화를 위한 He 기체 혼합, 고주파 전원, 유전체 플레이트의 조합 원리를 규명하며, 이는 플라즈마 응용 기술의 핵심 요소입니다. 또한 우라늄·Thorium 분離 기법 개발을 통해 지구화학 및 고체상태에서의 원소 분離 메커니즘을 탐구하고 있습니다. 연구는 표면 분석, 플라즈마 제어, 천연 우라늄-Thorium 계통의 고체상 동역학 등 다학제적 접근을 특징으로 합니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Some reasons are discussed for the stabilisation of a glow discharge at atmospheric pressure which was attained by controlling the following three conditions: the use of a high-frequency source, the use of He gas for dilution and the insertion of a dielectric plate between electrodes. The three conditions interact: the dielectric plate in a plasma forms the pulsed discharge from a low-frequency source, the fast duration of pulse current prevents a transition to an arc style discharge and a large
Some reasons are discussed for the stabilisation of a glow discharge at atmospheric pressure which was attained by controlling the following three conditions: the use of a high-frequency source, the use of He gas for dilution and the insertion of a dielectric plate between electrodes. The three conditions interact: the dielectric plate in a plasma forms the pulsed discharge from a low-frequency source, the fast duration of pulse current prevents a transition to an arc style discharge and a large
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A new chemical separation technique to isolate Th and U from silicate rocks was established by using two kinds of commercial extraction chromatographic resins. In the first column procedure, with U/TEVA·spec resin, almost all elements except Th and U were eluted by 4 M HNO(3). Th was then separated by using 5 M HCl, and U was finally isolated by successive addition of 0.1 M HNO(3). A significant amount of Zr still remained in the Th fraction, which was then further purified in the second column
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