Thermally-Induced Dielectric Relaxation Spectra in Three Aldohexose Monosaccharides
Abstract
Three aldohexose monosaccharides, D-glucose, D-mannose, and D-galactose, were examined by scanning temperature dielectric analysis (DEA) from ambient temperatures through their melts. Phase transitions, including glass transition (T g) and melting temperature (T m), were evaluated by differential scanning calorimetry (DSC). The monosaccharides were found to exhibit thermally-induced dielectric loss spectra in their amorphous-solid phase before melting. Activation energies for electrical charging of each of the monosaccharides were calculated from an Arrhenius plot of the tan delta (e″/e′, dielectric loss factor/relative permittivity) peak frequency versus reciprocal temperature in Kelvin. The DEA profiles were also correlated with the DSC phase diagrams, showing the changes in electrical behavior associated with solid–solid and solid–liquid transitions.
Publication
Journal of Thermal Analysis and Calorimetry (10/26/11)
Podiums
American Chemical Society (ACS) Central Region Meeting (05/20/09)*
Cleveland State University’s Thermal Analysis Seminar (04/18/09)
Posters
North American Thermal Analysis Society (NATAS) Conference (08/15/10)*
Cleveland State University’s College of Science Research Day (04/30/10)
Midwest Carbohydrate and Glycobiology Symposium (10/04/08)
*Presented by a colleague
Model Chemistry Study Of Choline And Urea Based Deep Eutectic Solvents
Abstract
Gaussian and GaussView software were utilized to characterize interactions between choline salts and urea, which form a deep eutectic solvent (DES). The initial system studied was choline chloride and urea, at a 1:2 molar ratio, which is also known as reline. Subsequent systems, substituting the chloride anion with other anions (fluoride, bromide, and hydroxide), were studied to show that the system with greater calculated strength of interaction will have more non-ideal physical properties, such as melting point (found in literature). Observations regarding structure related to counterion electron density and hydrogen bonding were made throughout the studies.
Publication
OhioLink ETD (12/2018)