A5040359616- Glass properties and applications
- Material Dynamics and Properties
- Ionic liquids properties and applications
- Liquid Crystal Research Advancements
- Perfectionism, Procrastination, Anxiety Studies
- Chemical Thermodynamics and Molecular Structure
- Healthcare professionals’ stress and burnout
- Doctoral Education Challenges and Solutions
- Ion-surface interactions and analysis
- Adsorption, diffusion, and thermodynamic properties of materials
- nanoparticles nucleation surface interactions
- Advanced Materials Characterization Techniques
- Surface and Thin Film Phenomena
- Phase-change materials and chalcogenides
University of Wisconsin–Madison
2016-2020
In situ AC nanocalorimetry was used to characterize vapor-deposited glasses of six mono- and di-alcohol molecules. Benzyl alcohol with high kinetic stability decreased heat capacity were prepared. When annealed above the glass transition temperature Tg, transformation these into supercooled liquid took 103.4 times longer than relaxation time (τα). This is similar other highly stable organic prepared by vapor deposition first clear demonstration an forming a glass. Vapor deposited five...
Spectroscopic ellipsometry was used to characterize vapor-deposited glasses of ethylbenzene (Tg = 115.7 K). For this system, previous calorimetric experiments have established that a transition the ideal glass state is expected occur near 101 K (the Kauzmann temperature, TK) if low-temperature supercooled liquid has properties based upon extrapolation from above Tg. Ethylbenzene were at substrate temperatures between 100 (∼0.86 Tg) and 116 (∼Tg), using deposition rates 0.02–2.1 nm/s. Down...
Previous work has shown that vapor-deposition can prepare organic glasses with extremely high kinetic stabilities and other properties would be expected from liquid-cooled only after aging for thousands of years or more. However, recent reports have some molecules form vapor-deposited limited stability when prepared using conditions to yield a stable glass. In this work, we vapor deposit 2-ethyl-1-hexanol over wide range deposition rates test several hypotheses why molecule does not highly...
In situ interdigitated electrode broadband dielectric spectroscopy was used to characterize the excess wing relaxations in vapor-deposited and aged glasses of methyl-m-toluate (MMT, Tg = 170 K). MMT displays typical spectra its supercooled liquid glasses. Physical vapor deposition produced with degrees suppression relaxation that varied systematically conditions, up a maximum more than factor 3. The glass deposited at relatively high temperature, 0.96 (163 K), showed same amount as...
In situ AC nanocalorimetry was used to characterize vapor-deposited glasses of three phosphates with increasing lengths alkyl side chains: trimethyl phosphate, triethyl and tributyl phosphate. The as-deposited were assessed in terms their reversing heat capacity, onset temperature, isothermal transformation time. Glasses a range kinetic stabilities prepared, including kinetically stable glasses, as indicated by high temperatures long times. Trimethyl phosphate forms similar many other...
In situ AC nanocalorimetry and dielectric spectroscopy were used to analyze films of vapor-deposited triphenyl phosphite. The goal this work was investigate the properties glasses known polyamorphic system determine which liquid is formed when glass heated. We find that phosphite forms a kinetically stable prepared at substrate temperatures 0.75-0.95Tg, where Tg transition temperature. Regardless temperature utilized during deposition phosphite, heating always ordinary supercooled (liquid...
This article describes a graduate student-led effort to develop climate survey assess, advocate for, and improve the well-being mental health of students postdocs in Department Chemistry at University Wisconsin–Madison. Graduate have an increased incidence depression relative general population, given transient nature student understanding addressing concerns can be challenging. The goal this is illustrate how students, with support departmental faculty, staff, existing on-campus resources,...