Freezing Behavior in Porous Materials : Theory and Experiment

• Autorzy: Śliwińska-Bartkowiak M. , Dudziak G. , Sikorski R. , Gras R. , Gubbins K. E. , Radhakrishnan R. , Kaneko K.
• Języki publikacji: EN

Abstrakty

EN

We report both experimental measurements and molecular simulations of the melting and freezing behavior of simple fluids in porous media. Activated carbon fibers, having a mean pore width of 1.7 nm, were chosen as the porous medium. Differential scanning calorimetry (DSC) and dielectric relaxation spectroscopy (DS) were used to determine the melting point in these materials. The melting point was found to be very sensitive to the relative strength of the fluid-wall interaction compared to the fluid-fluid interaction. Monte Carlo simulations and Landau free energy formalism were used to determine the shift in the melting point, Tm, for simple fluids in pores having repulsive, weakly attractive and strongly attractive walls. The strength of the interaction of the fluid with the pore wall is shown to have a large effect on the shift in Tm, with Tm being reduced for weakly attracting walls. The theory of corresponding states is used to compare the experimental results for several systems to the simulation results. This approach also provides a unified approach in understanding the diverse freezing behavior in porous media.

Słowa kluczowe

EN

simulation; phase transition; calorimetry; corresponding states; fluids; hysteresis

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 2001
• Tom: Vol. 75, nr 4
• Strony: 547--555
• Opis fizyczny: Bibliogr. 22 poz., rys.

Twórcy

autor

Śliwińska-Bartkowiak M.

• Institute of Physics, University of A. Mickiewicz, Umultowska 85, 61-614 Poznań, Poland

autor

Dudziak G.

• Institute of Physics, University of A. Mickiewicz, Umultowska 85, 61-614 Poznań, Poland

autor

Sikorski R.

• Institute of Physics, University of A. Mickiewicz, Umultowska 85, 61-614 Poznań, Poland

autor

Gras R.

• Institute of Physics, University of A. Mickiewicz, Umultowska 85, 61-614 Poznań, Poland

autor

Gubbins K. E.

• North Carolina State University, 113 Riddick Labs, Raleigh, NC 27695-7905, USA

autor

Radhakrishnan R.

• North Carolina State University, 113 Riddick Labs, Raleigh, NC 27695-7905, USA

autor

Kaneko K.

• Department of Chemistry, Faculty of Science, Chiba University, Yayoi 1-33, Inage, Chiba 263-8522, Japan

Bibliografia

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