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The Liquidus Temperature for Methanol-Water Mixtures at High Pressure and Low Temperature, with Application to Titan

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 نشر من قبل Andrew Dougherty
 تاريخ النشر 2018
  مجال البحث فيزياء
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Methanol is a potentially important impurity in subsurface oceans on Titan and Enceladus. We report measurements of the freezing of methanol-water samples at pressures up to 350~MPa using a volumetric cell with sapphire windows. For low concentrations of methanol, the liquidus temperature is typically a few degrees below the corresponding ice freezing point, while at high concentrations it follows the pure methanol trend. In the Ice-III regime, we observe several long-lived metastable states. The results suggest that methanol is a more effective antifreeze than previously estimated, and might have played an important role in the development of Titans subsurface ocean.



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