Figure S3. Linear relationships between the transitional temperature of nitric acid condensation (Tc , defined as the temperature at which the moles of total nitrate in the condensed phases equals to 5% of the initial moles of nitric acid and determined in this study.) and logarithm of MEA mole fraction (mol %) in total moles of RNCs (ammonia and MEA) in the system at 298K. All simulations have the same total moles of ammonia as 8.86895×10−8 and the same initial moles of HNO3 and H2SO4 as 1.11151×10−9­­ and 2.03777×10−11, respectively. The system has a fixed initial moles of water vapor as 0.07848 (equivalent to 60% RH at 263.15 K and 101,325 Pa in 1 m3).