| Project/Area Number |
15350001
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Physical chemistry
|
|---|
| Research Institution | Hokkaido University |
|---|
Principal Investigator |
ITAMI Toshio Hokkaido Univ., Graduate Sch.of Sci., Associate Professor, 大学院・理学研究科, 助教授 (40113518)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
WATANABE Masahito Gakushuuin University, Faculty of Science, Professor, 理学部, 教授 (40337902)
MIZUNO Akitoshi Gakushuuin University, Faculty of Science, Assistant, 理学部, 助手 (10348500)
|
|---|
| Project Period (FY) |
2003 – 2005
|
| Project Status |
Completed (Fiscal Year 2005)
|
| Budget Amount *help |
¥10,400,000 (Direct Cost: ¥10,400,000)
Fiscal Year 2005: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 2004: ¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2003: ¥4,900,000 (Direct Cost: ¥4,900,000)
|
|---|
| Keywords | liquid metals / eutectic alloys / concentration fluctuations / supercooling / 過去冷却 / ミクロ凝固 |
|---|
| Research Abstract |
The present investigator has found the existence of concentration fluctuations near the eutectic point in the homogeneous liquid phase of eutectic systems. The purposes of this research program are to establish the rigorous evidences for this concentration fluctuation and to present the detailed view about it. The EXAFS experiment in the Spring-8 for liquid deep eutectic system, Au-Ge, showed some evidence for the existence of such a concentration fluctuation. The precise measurements of electrical resistivity for "deep eutectic systems", Au-Si, Au-Ge, Ag-Si, Ag-Ge systems, showed the large concentration fluctuations, which amounts to 7 vol.%. The accurate electrical resistivity measurements for liquid "eutectic systems with multi eutectic points" showed an anomalous behavior around every eutectic composition in homogeneous liquid phases. The concentration fluctuation in the homogeneous liquid phase of eutectic composition may appear as the microscopic presolidification phenomena. This
… More
implies that the supercooling tendency of homogeneous liquids must be smallest at the eutectic composition. This proposal is different from the prevailing common sense about the eutectic liquids, which tells us that the eutectic liquid has the largest supercooling tendency and glass forming ability. The analysis of previous literatures about the homogeneous supercooling in some eutectic systems showed that the supercooling tendency of homogeneous liquid phase is smallest at the eutectic composition. Therefore, the supercooling behavior was investigated by the DSC experiments for liquid deep eutectic system, Au-Ge. Surely the supercoling tendency is smallest at the eutectic composition. This strongly supports the existence of concentration fluctuations around the eutectic composition in the homogeneous liquid phase. In future, the detailed structure analysis must be performed by the large scale computer simulations. It must be confirmed that the concentration fluctuations exist around the eutectic composition in the homogeneous liquid phase universally in various eutectic liquids of many kinds, such as ionic liquids, water solutions, etc. Less
|
