1995 Fiscal Year Final Research Report Summary
Elecronic critical phenomena under microgravity and gravity circumstances
| Project/Area Number |
06453012
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Physical chemistry
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| Research Institution | Hokkaido university |
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Principal Investigator |
ITAMI Toshio Graduate School of Science, Hokkaido University, Associate Professor, 大学院理学研究科, 助教授 (40113518)
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| Project Period (FY) |
1994 – 1995
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| Keywords | liquid metals / microgravity / thermal expansion coefficient / density / resistivity / spinodal / critical phenomena / two liquid separation |
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| Research Abstract |
In this science plan the two phase separation (TPS) for liquid alloys with critical mixing was investigated both under microgravity condition and under gravity condition with particular interest in the electronic properties in the critical phenomena. The electricl resistivity, R,was studied for liquid Hg-Ga, Cd-Ga and Bi-Ga alloys in a laboratory on the ground. The concentration dependence of resistivity, R,show a monotonous variation even around the critical concentration (CC). However, the temperature coefficients of resistivity (TCR) around CC show maximum behaviors for liquid Bi-Ga and Cd-Ga alloys and a minimum behavior for liquid Hg-Ga alloys. The concentration dependence of measured TCR for liquid Bi-Ga alloys shows a far larger maximum behavior at CC under microgravity, which was realized as the ELM project by the launch of S520-19 rocket belonging to the Institute of Space and Astronautical Science (ISAS) in Japan. These behaviors are explained by the degree of growth of concentration fluctuations near the critical point (CP). In addition to these, the supercooling behavior of homogeneous liquid (HL) was extracted from the behavior of R on cooling process. The degree of supercooling for Bi-Ga in the HL range was far larger under microgravity than under gravity conditions. The microgravity condition provides an ideal circumstance for the study of supercooling and spinodal behaviors.
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