1999 Fiscal Year Final Research Report Summary
Anisotropic Growth Kinetics and Pattern Formation of Ice
| Project/Area Number |
10044049
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| Research Category |
Grant-in-Aid for Scientific Research (B).
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
固体物性Ⅰ(光物性・半導体・誘電体)
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| Research Institution | Institute of Low Temperature Science, Hokkaido University |
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Principal Investigator |
FURUKAWA Yoshinori Hokkaido Univ., Inst. Low Temp Sci., Associate Professor, 低温科学研究所, 助教授 (20113623)
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| Co-Investigator(Kenkyū-buntansha) |
THUKAMOTO Katsuo Tohoku Univ., Graduate School of Science., Inst., 大学院・理学研究科, 助手 (60125614)
YOKOYAMA Etsurou Yamaguchi Univ., Facutly of Engneering, Associate Professor, 工学部, 助教授 (40212302)
GIGA Yoshikazu Hokkaido Univ. Graduate School of Science Professor, 大学院・理学研究科, 教授 (70144110)
NADA Hiroki National Institute Resource and Environment, Researcher, 資源環境技術総合研究所, 研究員
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| Project Period (FY) |
1998 – 1999
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| Keywords | Pattern formation / Ice crystal / Morphological instability / Diffusion field / Mullins-Sekerka instability / Interferometry / Molecular dynamics simulation |
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| Research Abstract |
Pattern formation mechanisms of ice crystals with the faceted faces were carried out in cooperation with the researchers of Carnegie-Mellon Univ. Pittsburgh.
First of all, pattern formation of ice crystal interface during the one-directional growth was observed in-situ using a Mach-Zehnde interferometer. A direct evidence for the constitutional supercooling, which develops in front of the interface, was first given from the analysis of diffusion field of impurity using the interference fringes. The Mullins-Sekerka instability theory, which is basically a linear and steady state theory, is also applicable to the pattern formation of ice interface.
Second, a new model for the ice disk growth of ice in the supercooled water was also developed on the basis of the experimental results for ice crystal growth.
As a result, we showed that there are two different modes for ice crystal processes in the supercooled water depending on the growth kinetics of basal faces (namely, the spiral growth or the two-dimensional nucleation growth of basal faces). This result gives the new prospect for the understanding of the pattern formation of crystals with faceted faces.
Third, the molecular dynamics simulations were .also carried out for the ice surfaces and the ice-water interfaces. The physical properties of quasi-liquid layers on the ice surfaces and the growth processes of ice crystals from the supercooled water were precisely discussed in the molecular level. Most important argument was that we showed the anisotropic growth modes between basal and prismatic interfaces of ice. We begin to develop a new model for the pattern formation of ice crystal on the basis of these results obtained in the period of this international project. Related symposiums about the pattern formation of crystals with faceted faces were also held in Sapporo twice during the project periods. More than 50 researchers were participated for both.
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