AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Application of Synchrotron Radiation for the Morphology and Internal Structure of Individual Aerosols
Chao-Wei Lai, Yu-Han Chen, Wan-Yi Chen, Chun-Chieh Wang, Yao-Tung Lin, LI-HAO YOUNG, China Medical University, Taiwan
Abstract Number: 392 Working Group: Instrumentation and Methods
Abstract The morphology of aerosols affects their transport, optical and hygroscopic properties. This study aims to utilize synchrotron-based transmission X-ray microscopy (TXM) 2D radiography and 3D tomography to identify the particle size, shape and internal structure of individual aerosols. Size-fractionated (2.5, 1, 0.5 and 0.25 μm) ambient aerosols were collected on transmission electron microscopy (TEM) grids, which were then subjected to TXM analysis at the National Synchrotron Radiation Research Center (NSRRC) in Taiwan. TXM 2D images were collected with 60s exposure time and a spatial resolution of about 60 nm. Subsequently, 3D images were reconstructed using sequential projections taken with the azimuth angle rotating from -90° to +90°. Transmission/scanning electron microscopy (TEM/SEM) images were also taken for comparison. Preliminary results show that the aerosols exhibited spherical, aggregate, rod, polygon and irregular shapes. More importantly, the synchrotron-based TXM 2D/3D images can reveal the complex internal structure of aerosols, including solid, porous, hallow or core-shell, that are not visible by TEM/SEM. In addition, heavy elements were found to be more associated with spherical aerosols. The outputs of this study provide us with new insights of the potential origin, formation mechanisms and aging processes of ambient aerosols.