Alla Zelenyuk uses laboratory and field studies to probe two questions important to understanding clouds and climate: the complex processes that govern the atmospheric lifecycle of aerosols and the characterization of combustion particles. She has conducted this research at PNNL since 2003. Zelenyuk earned her Ph.D. in chemical physics at the Moscow Institute of Physics and Technology in Russia and served as a research scientist at Semenov Institute of Chemical Physics in Moscow. In the U.S., she conducted research at the University of North Carolina at Chapel Hill and Brookhaven National Laboratory before joining PNNL. The dual-use tools she has developed aim to bridge the gap between fundamental and applied sciences, advancing the understanding of chemical and physical transformations of nanoparticles while also shedding light on the role of aerosols in cloud condensation and the nucleation of atmospheric ice.