Empirical and Theoretical Models of Equilibrium and Non-Equilibrium Transition Temperatures of Supplemented Phase Diagrams in Aqueous Systems

2016 ◽  
Author(s):  
Horacio R. Corti ◽  
C. Austen Angell ◽  
Tony Auffret ◽  
Harry Levine ◽  
M. Pilar Buera ◽  
...  
Keyword(s):  
Phase Diagrams ◽  
Theoretical Models ◽  
Transition Temperatures ◽  
Aqueous Systems ◽  
Equilibrium Transition ◽  
Non Equilibrium

Empirical and theoretical models of equilibrium and non-equilibrium transition temperatures of supplemented phase diagrams in aqueous systems (IUPAC Technical Report)

2010 ◽  
Vol 82 (5) ◽  
pp. 1065-1097 ◽  
Author(s):  
Horacio R. Corti ◽  
C. Austen Angell ◽  
Tony Auffret ◽  
Harry Levine ◽  
M. Pilar Buera ◽  
...  
Keyword(s):  
Glass Transition ◽  
Aqueous Solutions ◽  
Standard Procedure ◽  
Theoretical Models ◽  
Transition Curve ◽  
Concentrated Solution ◽  
Equilibrium Transition ◽  
Natural Foods ◽  
Freezing Curve ◽  
Non Equilibrium

This paper describes the main thermodynamic concepts related to the construction of supplemented phase (or state) diagrams (SPDs) for aqueous solutions containing vitrifying agents used in the cryo- and dehydro-preservation of natural (foods, seeds, etc.) and synthetic (pharmaceuticals) products. It also reviews the empirical and theoretical equations employed to predict equilibrium transitions (ice freezing, solute solubility) and non-equilibrium transitions (glass transition and the extrapolated freezing curve). The comparison with experimental results is restricted to carbohydrate aqueous solutions, because these are the most widely used cryoprotectant agents. The paper identifies the best standard procedure to determine the glass transition curve over the entire water-content scale, and how to determine the temperature and concentration of the maximally freeze-concentrated solution.

Dynamic Phase Diagrams And Non-equilibrium Lever Principle Of Carbon Steel

2006 ◽  
Vol 21 (1) ◽  
pp. 21-27 ◽  
Author(s):  
Q. Zou ◽  
H. Cao ◽  
Z. Wang ◽  
Z. Zhang ◽  
X. Chen
Keyword(s):  
Carbon Steel ◽  
Phase Diagrams ◽  
Dynamic Phase Diagrams ◽  
Dynamic Phase ◽  
Non Equilibrium

Non-equilibrium transition state rate theory

2014 ◽  
Vol 5 (10) ◽  
pp. 3761-3769 ◽  
Author(s):  
Haidong Feng ◽  
Kun Zhang ◽  
Jin Wang
Keyword(s):  
Transition State ◽  
Rate Theory ◽  
Equilibrium Processes ◽  
State Rate ◽  
Equilibrium Transition ◽  
Biological Equilibrium ◽  
Non Equilibrium

Transition state or Kramers' rate theory has been used to quantify the kinetic speed of many chemical, physical and biological equilibrium processes successfully.

Non-equilibrium freezing behaviour of aqueous systems

1977 ◽  
Vol 278 (959) ◽  
pp. 167-189 ◽  
Keyword(s):  
Heterogeneous Nucleation ◽  
Homogeneous Nucleation ◽  
Living Cells ◽  
Crystalline Form ◽  
Model Systems ◽  
Aqueous Systems ◽  
Melting Points ◽  
Simultaneous Representation ◽  
Thermodynamic Factors ◽  
Non Equilibrium

The tendencies to non-equilibrium freezing behaviour commonly noted in representative aqueous systems derive from bulk and surface properties according to the circumstances. Supercooling and supersaturation are limited by heterogeneous nucleation in the presence of solid impurities. Homogeneous nucleation has been observed in aqueous systems freed from interfering solids. Once initiated, crystal growth is often slowed and, very frequently, terminated with increasing viscosity. Nor does ice first formed always succeed in assuming its most stable crystalline form. Many of the more significant measurements on a given system can be combined and displayed in the form of a ‘supplemented phase diagram’, the latter permitting the simultaneous representation of thermodynamic and non-equilibrium properties. The diagram incorporates equilibrium melting points, heterogeneous nucleation temperatures, homogeneous nucleation temperatures, glass transition and devitrification temperatures, recrystallization temperatures, and, where appropriate, solute solubilities and eutectic temperatures. Taken together, the findings on model systems aid the identification of the kinetic and thermodynamic factors responsible for the freezing - thawing survival of living cells.

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