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Adiabatic and isothermal sound waves: the case of supercritical nitrogen

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 Added by Filippo Bencivenga
 Publication date 2005
  fields Physics
and research's language is English




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The acoustic sound dispersion of nitrogen in its liquid and supercritical phases has been studied by Inelastic X-Ray Scattering. Approaching supercritical conditions, the gradual disappearance of the positive sound dispersion, characteristic of the low temperature liquid, is observed. In the supercritical state, evidence for a crossover between adiabatic and isothermal sound propagation regimes is inferred by an analysis of the dynamic structure factor based on generalized hydrodynamics.



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