image: These are characteristic particle types observed during the experiment: (A) A droplet of secondoary organic material. (B) Mixed organic-inorganic particle. (C) Pyrogenic carbon particle with organic coating. (D) Mineral dust particle without coating. (E and F) Primary biological aerosol particle (E) with and (F) without organic coating. The organic droplets and coatings appear dark gray, filter pores appear black, and filter material appears light gray (8). view more
Credit: Courtesy of Scot Martin, Harvard School of Engineering and Applied Sciences, and colleagues.