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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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sub-T g aging and annealing T anneal.
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Phase transitions of 1st and 2nd order (Ehrenfest classification) Clausius-Clapeyron Ehrenfest
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Phase transitions of 1st and 2nd order (Ehrenfest classification)
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1st-order, 2nd-order and Lambda-type transitions v 1 v 2 s 1 s 2 c p, , T v 1 = v 2 s 1 = s 2 c p, , T v 1 = v 2 s 1 = s 2 c p1 c p2 1 2 T1 T2 [ T 1 = T 2 ; P 1 = P 2 ; g 1 = g 2 ]
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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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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 [M. A. R. et al., J. Non-Cryst. Solids 221 (1997) 170]
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the fictive temperature T f Ethanol [B. Kabtoul and M. A. R., Phys. Status Solidi A 208, 2249–2253 (2011)]
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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] Stokes-Einstein equation: [A. Einstein, Annalen der Physik 17, 549 (1905)]
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B2O3B2O3 o-terphenyl v HH
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