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https://hdl.handle.net/11681/5747| Title: | Self-diffusion in ice single crystals |
| Authors: | Hokkaido University. Itagaki, Kazuhiko |
| Keywords: | Ice ice crystals Self-diffusion Ice crystal structures Ice crystal structure Thermal properties Anisotropy |
| Publisher: | Cold Regions Research and Engineering Laboratory (U.S.) Engineer Research and Development Center (U.S.) |
| Series/Report no.: | Research report (Cold Regions Research and Engineering Laboratory (U.S.)) ; 178. |
| Description: | Research Report Abstract: Measurements of the diffusion constants in single crystals of ice in directions parallel and perpendicular to the c-axis are described. The anisotropy of activation energy was obtained. Natural ice crystals grown in the Mendenhall Glacier, Alaska, were used. After the crystallographic axes were determined by reflection goniometry from hoarfrost grown on the crystal surface, the samples were cut into disc-shaped specimens of desired orientations. The disc surface was smoothed by a microtome and activated by sublimation of tritiated water. The diffusion of the tritiated water molecules from the end plane was measured. The temperature of diffusion annealing was kept at -10°, -20° and -30°C within limits of 0. 5°C. The surface activity at a certain depth in the specimen was measured with a gas flow counter using Q-gas after each removal of a surface layer about 10 microns thick. Higher activation energy was observed perpendicular to the c-axis. This indicates the free interstitial molecular jump mechanism for diffusion. |
| Rights: | Approved for public release; distribution is unlimited. |
| URI: | http://hdl.handle.net/11681/5747 |
| Appears in Collections: | Research Report |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| CRREL-Research-Report-178.pdf | 1.1 MB | Adobe PDF |  View/Open |