Ultrasonic Attenuation in Ice Crystals near the Melting Temperature
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چکیده
Ultrasonic attenuation in crystals of ice Ih has been measured as functions of frequency (15 a 85 MHz) and temperature ( 8°C a O.l°C). Data were analyzed on the basis of vibrating string model of dislocation, and the following results have been obtained: Density of dislocations is on the order of 106 cm-*; pinning of dislocations may be due to impurity ions; dislocation density severely fluctuates with time near the melting point.
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تاریخ انتشار 2016