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https://hdl.handle.net/11681/5958| Title: | Self-diffusion in ice monocrystals |
| Authors: | Ramseier, René O. |
| Keywords: | Ice Ice crystal structure Ice molecular structure Ice crystals Ice crystal growth Ice crystal self-diffusion Diffusivity Artificial ice crystals |
| 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.)) ; 232. |
| Description: | Research Report 232 Abstract: The self-diffusion of tritium, parallel and perpendicular to the optical axis of naturally occurring and artificially grown ice mcnocrystals, was studied between -2.5 and -35.9°C. The artificial ice monocrystals were grown using a zone-melting technique. Activated samples were stored for several weeks, then sectioned by microtome and analyzed in a liquid scintillation counter to obtain the self-diffusion coefficients. The plane source solution of Fick's second law was used in treating the data. The diffusion coefficients were found to be identical for both types of ice. A slight anisotropy was found due to the geometry of the crystal; however, the activation energy was found to be 0.62 𝖾 𝖵 for all cases. Based on the experimental data, it is concluded that the diffusion takes place by a vacancy mechanism and that entire H2O molecules are diffusing, i.e., molecular diffusion occurs. Theoretical calculations using the atomic diffusion theory and Zener's theory for 𝖣0 are in excellent agreement with the experimentally determined diffusion coefficient. |
| Rights: | Approved for public release; distribution is unlimited. |
| URI: | http://hdl.handle.net/11681/5958 |
| Appears in Collections: | Research Report |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| CRREL-Research-Report-232.pdf | 14.34 MB | Adobe PDF |  View/Open |