| Project/Area Number |
10650670
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Inorganic materials/Physical properties
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| Research Institution | Yokohama City University, Faculty of Science |
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Principal Investigator |
KOJIMA Kenichi Faculty of Science Yokohama City Univ. Prof., 理学部, 教授 (90046095)
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| Co-Investigator(Kenkyū-buntansha) |
TACHIBANA Masaru Faculty of Science Yokohama City Univ. Research Associate, 理学部, 助手 (80236546)
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| Project Period (FY) |
1998 – 1999
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| Project Status |
Completed (Fiscal Year 1999)
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| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 1999: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1998: ¥3,000,000 (Direct Cost: ¥3,000,000)
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| Keywords | Mechanical Properties of fullerene crystals / Strength of fullerene crystals / Raman peaks of fullerene crystals / Dislocations in fullerene crystals / C60膜のラマン分光 / フラーレン結晶 / 結晶の強度 / 光ポリマー / 光照射硬化 / 転位 / 微小かたさ / C_<60>結晶 / C_<70>結晶 |
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| Research Abstract |
We carried out the experiments of Vickers micro-hardness of C60 and C70 crystals. As results, we have found that the micro-hardness of C60 and C70 crystals increased after they are illuminated with white light. We call this phenomenon "Photo-illumination hardening". The results are as following,
1. The hardness increases with illumination of time, and then approaches a constant value.
2. The hardening depends on the specimen temperature, and disappears at temperatures higher than 400K.
3. The hardness strongly depends on the wavelength of illumination of light. The magnitude of the hardness reaches a maximum at 700nm.
4. The Raman peaks of C60 crystals, which were illuminated as a function of illumination time, shift from an intrinsic peak 1469cmィイD1-1ィエD1 to a photo-polymerized peak 1460 cmィイD1-1ィエD1 via 1465 cmィイD1-1ィエD1 and 1464 cmィイD1-1ィエD1.
5. In case of C70 crystals, we also observed the same kinds of behaviors due to photo-illumination. although the illumination time needs more longer.
From these results, we conclude the hardening is due to the photo-induced polymers of C60 or C70.
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