Temperature dependent phase transitions of aerosol droplets

I designed and developed microfluidic devices and experimental protocols for studying phase changes such as liquid-liquid phase separation (LLPS) and efflorescence (crystallization) in aerosol droplets as a function of temperature, relative humidity and organic to inorganic ratio of solutes. For this project, I led a group of graduate students from UMN and UC San Diego to perform complementary experiments. I performed a cost analysis before purchasing a temperature-controlled static stage, designed and fabricated microfluidic devices to use with the stage, performed the microfluidic experiments and performed confocal Raman spectroscopic studies on phase separated droplets to identify the chemical nature of separated phases.

Publications

• Roy P., Liu S., Dutcher C.; Droplet interfacial tensions and phase transitions measured in microfluidic channels. Annual Reviews in Physical Chemistry, 72, In press.

• Roy P., Mael L., Makhnenko I., Martz R., Grassian V. & Dutcher C.; Temperature-dependent phase transitions of aqueous aerosol droplet systems in microfluidic traps. ACS Earth and Space Chemistry, 2020, 4(9), 1527-1539.

• Roy P., Liu S. & Dutcher C.; Modeling and microfluidic measurements of surface tension and phase behavior in aerosol systems. Annual Meeting of Center for Aerosol in the Chemistry of the Environment (CAICE), UC San Diego, November 5-7, 2018, San Diego, CA. Podium Talk.