Linked Life Data

16942349

Source:http://linkedlifedata.com/resource/pubmed/id/16942349

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2006-8-31
pubmed:abstractText
For nonpolymeric supercooled liquids, the empirical correlation m = 56Tg DeltaCp(Tg)/DeltaHm provides a reliable means of correlating dynamic and thermodynamic variables. The dynamics are characterized by the fragility or steepness index m and the glass transition temperature Tg, while thermodynamics enter in terms of the heat capacity step DeltaCp at Tg and the melting enthalpy DeltaHm. The combination of the above correlation with the 23 rule for the Tg/Tm ratio yields an expression, m = 40DeltaCp(Tg)/DeltaSm, which was rationalized as the correlation of the thermodynamic and kinetic fragilities. Defining a thermodynamic fragility via DeltaCp(Tg)/DeltaSm also reveals that the slopes in Kauzmann's original DeltaS(T)/DeltaSm versus T/Tm plot reflect the fragility concept [Chem. Rev. 43, 219 (1948)], so long as Tm/Tg = 1.5. For the many liquids whose excess heat capacity is a hyperbolic function of temperature, we deduce that the fragility cannot exceed m = 170, unless the Tg/Tm = 2/3 rule breaks down.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9606
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
125
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
074505
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Fragility and thermodynamics in nonpolymeric glass-forming liquids.
pubmed:affiliation
Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't