| Project/Area Number |
08650060
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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 |
Applied physics, general
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| Research Institution | HOKKAIDO UNIVERSITY |
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Principal Investigator |
HORIGUCHI Kaoru Institute of Low Temperature Science, Hokkaido Univ., Asso.Pro., 低温科学研究所, 助教授 (60001658)
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| Co-Investigator(Kenkyū-buntansha) |
MIZUNO Yukiko Institute of Low Temperature Science, Hokkaido Univ., Asso.Pro., 低温科学研究所, 助教授 (10002461)
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| Project Period (FY) |
1996 – 1998
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| Project Status |
Completed (Fiscal Year 1998)
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| Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1998: ¥100,000 (Direct Cost: ¥100,000)
Fiscal Year 1997: ¥100,000 (Direct Cost: ¥100,000)
Fiscal Year 1996: ¥1,700,000 (Direct Cost: ¥1,700,000)
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| Keywords | Adhesive strength / Hydrophobic / Contact angle / Unfrozen water / Surface roughness / Cohesive strength |
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| Research Abstract |
Many works have been done on the adhesive properties of ice from the point of view of mechanics, basing upon the general view that substances with which water forms a large contact angle adhesive less to ice than those which show a small contact angle. However, we found that snow cover on glass slide well compared with Teflon near 0ﾟC.In order to make clear this phenomenon, shear experiment for ice adhesion on glass and Teflon with smooth surface were carried out in the temperature range of - 1ﾟC to -15ﾟC.Force and energy were supplied to the ice by a driving motor through a steel rod and the load cell which has an elastic displacement of 6.5 mu m per 10 kgw. There are two types of failure in a stress-time curve, that is, brittle failure and viscous failure. Teflon showed only the brittle failure. The other side, the failure type of glass is brittle at temperature lower than about -7ﾟC, and is viscous at temperature higher than -7ﾟC.The magnitude of shear strength of glass is larger than that of Teflon at temperature lower than about -5ﾟC, but this relationship reversed at temperature higher than -3ﾟC.Adhesion work for brittle failure is directly proportional to square of shear strength. Then, we got the relationship between shear strength and temperature for brittle failure and the relationship between the energy being supplied by a driving motor to make viscous failure and temperature.
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