| Project/Area Number |
06555251
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| Research Category |
Grant-in-Aid for Developmental Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
工業分析化学
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| Research Institution | HOKKAIDO UNIVERSITY |
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Principal Investigator |
ICHIKAWA Tsuneki Hokkaido Univ., Fac.of Eng., Assoc.Prof., 工学部, 助教授 (10001942)
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| Co-Investigator(Kenkyū-buntansha) |
TACHIKAWA Hiroto Hokkaido Univ., Fac.of Eng., Instructor, 工学部, 助手 (10207045)
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| Project Period (FY) |
1994 – 1995
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| Project Status |
Completed (Fiscal Year 1995)
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| Budget Amount *help |
¥4,600,000 (Direct Cost: ¥4,600,000)
Fiscal Year 1995: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 1994: ¥3,300,000 (Direct Cost: ¥3,300,000)
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| Keywords | ESR / Instrument / Adiabatic rapid-passage / Time domain ESR / ポリシラン / 高速ESR / パルス磁場 / 非断熱測定 / 高速磁場掃引 |
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| Research Abstract |
A fast and sensitive ESR spectrometer was developed for detecting 10^-15 mole of paramagnetic centers in cryogenic solids within 100 microseconds. The spectrometer detected transient ESR signals generated during adiabatic rapid-passage through the on-resonant condition of paramagnetic centers. The adiabatic passage by the rapid sweep of the magnetic field was much better than the frequency sweep, since a voltage-controlled microwave oscillator for the frequency sweep generated phase noises which induced irregular oscillation of the signal amplitude. The adiabatic passage was attained by applying microwave pulses while sweeping the magnetic field repeatedly. The numerical analysis of the transient ESR signals revealed that the adiabatic rapid passage was suitable for detecting paramagnetic centers with the transverse relaxation time longer than 100 microseconds. The sensitivity of the spectrometer for such a sample was 100 times more than a conventional CW ESR spectrometer. It was concluded that the adiabatic rapid-passage ESR spectrometer was quite powerful for detecting a very small amount of paramagnetic centers with very long relaxation times such as organic free radicals in cryogenic solids.
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