2012 Fiscal Year Final Research Report
A novel technique for gas hydrate study using terahertz spectroscopy
| Project/Area Number |
23760846
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Energy engineering
|
|---|
| Research Institution | Nagoya University |
|---|
Principal Investigator |
TAKEYA Kei 名古屋大学, 工学研究科, 助教 (70515874)
|
|---|
| Project Period (FY) |
2011 – 2012
|
| Keywords | 自然エネルギーの利用 / テラヘルツ波 / メタンハイドレート |
|---|
| Research Abstract |
The optical and dielectric properties of gas hydrates at THz frequencies are expected to provide meaningful information. The present study reports a THz-TDS study of gas hydrates over a wide temperature range (10-250 K) at atmospheric pressure. The real and imaginary dielectric constants ε' and ε'' of SF6 hydrate have been measured in the frequency range 0.3-1.2 THz and in the temperature range 10.3-240 K using THz-TDS with a gas cooling cryostat. The constant ε' increases with frequency, and its mathematical analysis of the increase in ε', shows a local maximum at a few THz. The polarizability ε obtained from ε' shows a linear increase against the square of temperature. The constant ε'', which is mainly influenced by infrared phonon absorption, increases with frequency and temperature over the entire range considered in this study. We discuss the frequency and temperature dependence of ε'' using a mathematical model and obtain parameters to describe the fitted curves of ε''. We check our results using a mathematical model for ice.
|
