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Is Soret equilibrium a non-equilibrium effect?

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 نشر من قبل Alois Wuerger
 تاريخ النشر 2014
  مجال البحث فيزياء
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 تأليف Alois Wurger




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Recent thermophoretic experiments on colloidal suspensions revived an old debate, namely whether the Soret effect is properly described by thermostatics, or necessarily requires non-equilibrium thermodynamics. Based on colloidal transport theory and the entropy production of the related viscous flow, our analysis leads to the conclusion that the equilibrium approach may work for small ions, yet fails for colloidal particles and polymers. Regarding binary molecular mixtures, our results shed some doubt on the validity of thermostatic approaches that derive the Soret coefficient from equilibrium potentials.



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