Journal ArticleDOI
Evaluation of Thermal Transitions in Some Cholesteryl Esters of Saturated Aliphatic Acids
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In this paper, the heats and temperatures of transition for fourteen cholesteryl esters of saturated aliphatic acids have been evaluated using a Perkin-Elmer Differential Scanning Calorimeter, DSC-IB.Abstract:
The heats and temperatures of transition for fourteen cholesteryl esters of saturated aliphatic acids have been evaluated using a Perkin-Elmer Differential Scanning Calorimeter, DSC-IB. Most esters tested were first recrystallized from n-pentyl alchol. Among several recrystallization solvents tested, n-pentyl alchol was most effective in removing impurities and eliminating ester transitions caused by these impurities. Ester purity was determined by a recently reported technique which is based on an analysis of the complete DSC recorder scan for transitions. The transition data in this study indicate that the lowest molecular weight saturated aliphatic ester of cholesterol to show mesophase behavior is the propionate. For the formate or acetate less pure samples may be supercooled in the melt so that mesophases may be observed. New transition data for the odd esters of cholesterol from undecanoate to nonadecanoate have also been obtained. Cholesteryl eicosanoate was examined and found to have only...read more
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Simple Molecular Model for the Smectic A Phase of Liquid Crystals
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Phase Transition Enthalpy Measurements of Organic and Organometallic Compounds and Ionic Liquids. Sublimation, Vaporization, and Fusion Enthalpies from 1880 to 2015. Part 2. C11–C192
TL;DR: A collection of phase change enthalpies of organic molecules including fusion, vaporization, and sublimation enthalphies for organometallic, ionic liquids, and a few inorganic compounds can be found in this paper.
Journal ArticleDOI
Divergence of Cholesteric Pitch near a Smectic-A Transition
TL;DR: In this paper, the authors measured the detailed temperature dependence of the cholesteric pitch in cholesteryl nonanoate near the smectic-$A$ transition and showed a power-law behavior with an exponent of 0.025.
Journal ArticleDOI
Physical properties of cholesteryl esters.
TL;DR: The phasebehavior of cholesteryl ester molecules is complex and cannot be determined a priori from the phase behavior of component cholesterol and fatty acid, so the data presented here should provide insight into the biological behavior of this lipid class.
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