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Title: Highly precise experimental device for determining the heat capacity of liquids under pressure

Abstract

An experimental device for making isobaric heat capacity measurements of liquids under pressure is presented. The device is an adaptation of the Setaram micro-DSC II atmospheric-pressure microcalorimeter, including modifications of vessels and a pressure line allowing the pressure in the measurement system to be set, controlled, and stabilized. The high sensitivity of the apparatus combined with a suitable calibration procedure allows very accurate heat capacity measurements under pressure to be made. The relative uncertainty in the isobaric molar heat capacity measurements provided by the new device is estimated to be 0.08% at atmospheric pressure and 0.2% at higher levels. The device was validated from isobaric molar heat capacity measurements for hexane, nonane, decane, undecane, dodecane, and tridecane, all of which were highly consistent with reported data. It also possesses a high sensitivity as reflected in its response to changes in excess isobaric molar heat capacity with pressure, which were examined in this work for the first time by making heat capacity measurements throughout the composition range of the 1-hexanol+n-hexane system. Finally, preliminary measurements at several pressures near the critical conditions for the nitromethane+2-butanol binary system were made that testify to the usefulness of the proposed device for studying critical phenomenamore » in liquids under pressure.« less

Authors:
; ; ; ; ; ;  [1];  [2]
  1. Departamento de Fisica Aplicada, Facultad de Ciencias de Ourense, As Lagoas s/n, 32004 Ourense (Spain)
  2. (France)
Publication Date:
OSTI Identifier:
20953457
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 5; Other Information: DOI: 10.1063/1.2736776; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; ATMOSPHERIC PRESSURE; BUTANOLS; CALIBRATION; CALORIMETERS; CALORIMETRY; CONTAINERS; DECANE; DODECANE; EQUIPMENT; HEXANE; LIQUIDS; NITROMETHANE; SENSITIVITY; SPECIFIC HEAT

Citation Formats

Gonzalez-Salgado, D., Valencia, J. L., Troncoso, J., Carballo, E., Peleteiro, J., Romani, L., Bessieres, D., and Laboratoire de Fluides Complexes, Groupe Haute Pression, Universite de Pau et des Pays de l'Adour, BP 1155, 64013 Pau. Highly precise experimental device for determining the heat capacity of liquids under pressure. United States: N. p., 2007. Web. doi:10.1063/1.2736776.
Gonzalez-Salgado, D., Valencia, J. L., Troncoso, J., Carballo, E., Peleteiro, J., Romani, L., Bessieres, D., & Laboratoire de Fluides Complexes, Groupe Haute Pression, Universite de Pau et des Pays de l'Adour, BP 1155, 64013 Pau. Highly precise experimental device for determining the heat capacity of liquids under pressure. United States. doi:10.1063/1.2736776.
Gonzalez-Salgado, D., Valencia, J. L., Troncoso, J., Carballo, E., Peleteiro, J., Romani, L., Bessieres, D., and Laboratoire de Fluides Complexes, Groupe Haute Pression, Universite de Pau et des Pays de l'Adour, BP 1155, 64013 Pau. Tue . "Highly precise experimental device for determining the heat capacity of liquids under pressure". United States. doi:10.1063/1.2736776.
@article{osti_20953457,
title = {Highly precise experimental device for determining the heat capacity of liquids under pressure},
author = {Gonzalez-Salgado, D. and Valencia, J. L. and Troncoso, J. and Carballo, E. and Peleteiro, J. and Romani, L. and Bessieres, D. and Laboratoire de Fluides Complexes, Groupe Haute Pression, Universite de Pau et des Pays de l'Adour, BP 1155, 64013 Pau},
abstractNote = {An experimental device for making isobaric heat capacity measurements of liquids under pressure is presented. The device is an adaptation of the Setaram micro-DSC II atmospheric-pressure microcalorimeter, including modifications of vessels and a pressure line allowing the pressure in the measurement system to be set, controlled, and stabilized. The high sensitivity of the apparatus combined with a suitable calibration procedure allows very accurate heat capacity measurements under pressure to be made. The relative uncertainty in the isobaric molar heat capacity measurements provided by the new device is estimated to be 0.08% at atmospheric pressure and 0.2% at higher levels. The device was validated from isobaric molar heat capacity measurements for hexane, nonane, decane, undecane, dodecane, and tridecane, all of which were highly consistent with reported data. It also possesses a high sensitivity as reflected in its response to changes in excess isobaric molar heat capacity with pressure, which were examined in this work for the first time by making heat capacity measurements throughout the composition range of the 1-hexanol+n-hexane system. Finally, preliminary measurements at several pressures near the critical conditions for the nitromethane+2-butanol binary system were made that testify to the usefulness of the proposed device for studying critical phenomena in liquids under pressure.},
doi = {10.1063/1.2736776},
journal = {Review of Scientific Instruments},
number = 5,
volume = 78,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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