Fig. 3. (a) Fractional change in droplet size over 1500 s for a MA/sucrose droplet at three different RHs, 70% (black), 50% (red) and 30% (blue), showing the gradual retardation to the evaporation of MA as the RH decreases. The range of the fractional change for the mixture at 10% RH is shown by the green envelope (data not explicitly shown for clarity). (b) Estimates of the effective vapour pressure at each RH step tend toward the reported pure component vapour pressure of aqueous MA (blue band) at high RHs.