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3. THE GLASS STATE AND THE GLASS TRANSITION: THERMODYNAMIC and KINETIC ASPECTS
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Differential Scanning Calorimetry Differential Thermal Analysis
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Is the glass transition a true thermodynamic phase transition ? T g depends on the cooling rate T g depends on the thermal history
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Ehrenfest relations Prigogine-Defay ratio must be = 1 if it were a phase transition with a single order parameter
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sub-T g aging and annealing T anneal.
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using Differential Scanning Calorimetry (DSC, TMDSC…) [J. M. Hutchinson, Thermochimica Acta 324 (1998) 165-174
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using Differential Scanning Calorimetry
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the fictive temperature T f B2O3B2O3
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Ethanol
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the fictive temperature T f phenomenological Tool-Narayanaswamy-Moynihan (TNM) approach [ Tool, J. Am. Ceram. Soc. 29 (1946) 240. Narayanaswamy, J. Am. Ceram. Soc. 54 (1971) 491. Moynihan et al., J. Am. Ceram. Soc. 59 (1976) 12. ] curve fitting method: [I. M. Hodge, J. Non-Cryst. Solids 169 (1994) 211]
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THE KAUZMANN PARADOX EXCESS OF ENTROPY: TKTK
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W. Kauzmann, Chem. Rev. 43, 219 (1948)
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THE KAUZMANN PARADOXNN 1.0
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STRONG AND FRAGILE GLASS-FORMING LIQUIDS 01
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Vogel-Tamman-Fulcher equation: (D: strength) fragility index m:
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STRONG AND FRAGILE GLASS-FORMING LIQUIDS C. A. Angell, J. Non-Cryst. Solids 102, 205 (1988)
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[I. Chang and H. Sillescu] Ecuación de Stokes-Einstein: [A. Einstein, Annalen der Physik 17, 549 (1905)]
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