Development of Heat Capacity Spectroscopy and Application to Relaxation Process in Amorphous Materials
| Project/Area Number |
62850120
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| Research Category |
Grant-in-Aid for Developmental Scientific Research
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| Allocation Type | Single-year Grants |
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| Research Field |
Physical properties of metals
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| Research Institution | Tokyo Institute of Technology |
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Principal Investigator |
SAITO Yasutoshi (1988) The Research Laboratory of Engineering Materials, Tokyo Institute of Technology, Professor, 工業材料研究所, 教授 (40005236)
斎藤 安俊 (1987) 東京工業大学, 工業材料研究所, 教授
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| Co-Investigator(Kenkyū-buntansha) |
MAESONO Akikazu SINKU-RIKO Inc., Director of President, 取締役社長
ITO Yoshitaka The Research Laboratory of Engineering Materials, Tokyo Institute of Technology,, 工業材料研究所, 助手 (70016822)
MARUYAMA Toshio Tokyo Institute of Technology, 工学部, 助教授 (20114895)
ATAKE Tooru The Research Laboratory of Engineering Materials, Tokyo Institute of Technology,, 工業材料研究所, 助教授 (30028229)
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| Project Period (FY) |
1987 – 1988
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| Project Status |
Completed (Fiscal Year 1988)
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| Budget Amount *help |
¥9,000,000 (Direct Cost: ¥9,000,000)
Fiscal Year 1988: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1987: ¥8,000,000 (Direct Cost: ¥8,000,000)
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| Keywords | Heat capacity spectroscopy / Ac method / Amorphous materials / Liquid crystals / Glass transition / 緩和機構 |
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| Research Abstract |
The frequency dependence of the heat capacity is expected to be observed near the glass transition temperature of a supercooled material. However, the maximum measurable frequency in conventional ac calorimetry is ultimately limited by the thermal divvusivity and the size of sample. The purpose of this research is to develop a new technique that makes it possible to obtain the frequency-dependent heat capacities over a wide range of frequency between 1 Hz and 100 kHz.
A cryostat working in a temperature region from liquid helium temperature up to ablut 100゜c and a high-precision system for temperature control have been constructed. The electrical circuits using a lock-in amplifier have been also constructed for heat capacity measurements on the basis of ac method. The calorimetry system has been automated by using a microcomputer. A thin metal resistor element for the use as heater/thermometer has been devised by vapor deposition(Ni, Au) and rf sputtering(Au, Pt). It has been found that the measurement system can be simplified by combining the two elements with the same temperature coefficient of resistance. A thin wire method has been also developed. The performance of the system has been tested by doing experiments on the blass transition of glycerol. The materials of liquid crystals have been also studied. Thermodynamic properties of pentylcyanobiphenyl and the related compounds (replacing the benzene ring by cyclohexane ring) have been studied by DTA, heat capacity measurements and Raman spectroscopy. The relaxation mechanisms have been discussed about the blass transition phenomena of the mixtures.
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Report
(2 results)
Research Products
(5 results)
