Glass transition temperatures and glass-forming region of the system lithium chloride-dimethyl sulphoxide-water

1985 ◽  
Vol 50 (5) ◽  
pp. 1161-1167
Author(s):  
Jarmila Malá ◽  
Ivo Sláma
Keyword(s):  
Glass Transition ◽  
Mixed Solvent ◽  
Solid Phase ◽  
Aqueous System ◽  
Transition Temperatures ◽  
Constant Composition ◽  
Glass Transition Temperatures ◽  
Glass Forming ◽  
Complicated Pattern ◽  
Phase Nucleation

Glass transition temperatures (Tg) of the system LiCl-DMSO-H2O have been measured. A small addition of DMSO to the binary aqueous system removes its unusual variation of Tg with salt concentration. The concentration dependence of Tg of the ternary system at a constant composition of the mixed solvent can be described by a linear equation. The variation in Tg with the mixed solvent composition at constant LiCl concentration follows a complicated pattern which cannot be described by commonly used relations. The boundaries of glass-forming region are discussed in terms of the effect of a change in solution composition on the induction period of equilibrium solid phase nucleation.

Glass transition temperatures in the system calcium chloride-water-dimethylsulphoxide

1983 ◽  
Vol 48 (6) ◽  
pp. 1558-1563
Author(s):  
Jarmila Malá ◽  
Ivo Sláma
Keyword(s):  
Glass Transition ◽  
Transition Temperature ◽  
Mole Fraction ◽  
Mixed Solvent ◽  
Transition Temperatures ◽  
Composition Region ◽  
Glass Transition Temperatures ◽  
Glass Forming ◽  
Dmso System ◽  
Chloride Water

The glass-forming composition region of the CaCl2-H2O-DMSO system has been established, and the glass transition temperatures of the mixtures have been determined as a function of the CaCl2 content at a constant DMSO mole fraction in the mixed solvent. The dependence of the glass transition temperature on the CaCl2 mole fraction at a constant mole fraction of DMSO in the mixed solvent can be described by a linear relationship.

Glass formation and glass structure of BiO1.5–CuO–Ca0.5Sr0.5O system

1989 ◽  
Vol 4 (4) ◽  
pp. 911-915 ◽  
Author(s):  
Haixing Zheng ◽  
Ren Xu ◽  
J. D. Mackenzie
Keyword(s):  
Glass Transition ◽  
Glass Formation ◽  
Glass Structure ◽  
Molecular Volume ◽  
Transition Temperatures ◽  
Glass Transition Temperatures ◽  
Glass Forming ◽  
Glass Rods

The glass-forming region of the BiO1.5–CuO–Ca0.5Sr0.5O system has been determined by melting 5 g batches. Glass rods 4 mm in diameter and 75 mm long have been made. The glass transition temperatures (TG) and the onset crystallization temperatures (Tx) are around 390 °C and 440 °C, respectively. Densities of these glasses range from 5.5 to 7.0 g/cm3. The glass structure consists of the [BiO3] and [BiO6] units, and the conversion between these two polyhedra mainly depends on the Ca0.5Sr0.5O amount. The molecular volume of the glasses indicated that increasing Ca0.5Sr0.5O caused loose glass structures.

scholarly journals Kinetic Controlled Glass Transition Measurement of Organic Aerosol Thin Films Using Broadband Dielectric Spectroscopy

2018 ◽  
Author(s):  
Yue Zhang ◽  
Shachi Katira ◽  
Andrew Lee ◽  
Andrew T. Lambe ◽  
Timothy B. Onasch ◽  
...  
Keyword(s):  
Glass Transition ◽  
Dielectric Spectroscopy ◽  
Solid Phase ◽  
Organic Aerosols ◽  
Transition Temperatures ◽  
Glass Transitions ◽  
Relaxation Rates ◽  
Cooling Rates ◽  
Glass Transition Temperatures ◽  
Broadband Dielectric Spectroscopy

Abstract. Glass transitions from liquid to semi-solid and solid phase states have important implications for reactivity, growth, and cloud forming (cloud condensation nuclei and ice nucleation) capabilities of secondary organic aerosols (SOA). The small size and relatively low mass concentration of SOA in the atmosphere make it difficult to measure atmospheric SOA glass transitions using conventional methods. To circumvent these difficulties, we have adopted a new technique for measuring glass forming properties of atmospherically relevant organic aerosols. Aerosol particles to be studied are deposited in the form of a thin film onto an interdigitated electrode (IDE) using electrostatic precipitation. Dielectric spectroscopy provides dipole relaxation rates for organic aerosols as a function of temperature (373 to 233 K) that are used to calculate the glass transition temperatures for several cooling rates. IDE-enabled broadband dielectric spectroscopy (BDS) was successfully used to measure the kinetically controlled glass transition temperatures of glycerol and citric acid aerosols with selected cooling rates. The glass transition results agree well with available literature data for these two compounds. The results indicate that the IDE-BDS method can provide accurate glass transition data for organic aerosols under atmospheric conditions. The BDS data obtained with the IDE-BDS technique can be used to characterize glass transitions for both simulated and ambient organic aerosols and to model their climate effects.

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