Abstract View
Exploring the Physicochemical Properties of Aerosol Using a Linear Quadrupole Electrodynamic Balance
JAMES F. DAVIES, Jack Choczynski, Chelsea Price, Brandon Wallace, Thomas Preston, Ryan Davis, University of California, Riverside
Abstract Number: 26
Working Group: Aerosol Chemistry
Abstract
From seeding clouds to scattering and absorbing light, aerosol play a significant role in the atmosphere and have profound effects on the global environment. To fully anticipate the changing impacts of aerosol over their lifetime, we must understand how key physicochemical properties develop as evaporation/condensation, oxidative aging and other chemical mechanisms evolve the composition of the particle phase.
We have developed a suite of methods based around single particle levitation using a linear quadrupole electrodynamic balance. The radius and refractive index of micron-sized aerosol particles is measured using Mie resonance spectroscopy and compositional information is determined by coupling to paper spray mass spectrometry. With these methods we explore the hygroscopicity, optical properties, phase morphology and mass transport in droplet samples in a contactless manner, allowing us to effectively simulate environmental conditions.
In this work, we report a newly developed dual-droplet approach that allows us to accurately quantify in-situ relative humidity and report hygroscopic growth for a range of model aerosol particle systems. Additionally, we explore the use of aerodynamic forces to characterize the density of levitated samples. We will focus discussion on mixed organic and inorganic particles (calcium chloride and sugars; citric acid and ammonium sulfate) that have recently been shown to exhibit interesting phase morphologies, such as gel formation, and water transport characteristics.