Effects of NO<i>_y</i> Aging on the Dehydration Dynamics of Model Sea Spray Aerosol

作     者：Woods, Ephraim, III Heylman, Kevin D. Gibson, Amanda K. Ashwell, Adam P. Rossi, Sean R. 

作者机构：Colgate Univ Dept Chem Hamilton NY 13346 USA 

出 版 物：《JOURNAL OF PHYSICAL CHEMISTRY A》 (J Phys Chem A)

年 卷 期：2013年第117卷第20期

页      面：4214-4222页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 070304[理学-物理化学(含∶化学物理)] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 0702[理学-物理学] 

基　　金：National Science Foundation [CHE-1012224] Direct For Mathematical & Physical Scien Division Of Chemistry [1012224, 0963223] Funding Source: National Science Foundation 

主　　题：DEHYDRATION (Chemistry) AEROSOL spray analysis NITRIC oxide analysis ANION separation MORPHOLOGY NITRATES PHASE transformations (Physics) 

摘      要：The reactions of NO, species in the atmosphere with sea spray aerosol replace halogen anions with nitrate. These experiments show the effect of increasing the nitrate content of model sea spray aerosol particles on the morphology changes and the phase transitions driven by changes in relative humidity (RH). The components of the model particles include H2O, Na+, Mg2+, Cl-, NO3-, and SO42-. Tandem differential mobility analyzer (TDMA) measurements yield the water content and efflorescence relative humidity (ERH) of these particles, and probe molecule spectroscopic measurements reveal subsequent phase transitions and partially characterize the salt composition on the surface of dry particles. The results show three effects of increasing the nitrate composition: decreasing the EFH (46 to 29%), production of a metastable aqueous layer on the surface of effloresced particles, and decreasing the sulfate content near the surface of dry particles. For the mixtures studied here, the initial crystallization event NaCl. For particles that contain a substantial metastable aqueous layer following efflorescence, probe molecule spectroscopy shows a second crystallization at a lower RI-I. This subsequent phase transition is likely the formation of Na2SO4. Homogeneous nucleation theory (HNT) using a semiempirical formulation predicts the ERR of all mixtures within 2.0% RH, with a mean absolute deviation of 1.0%. The calculations suggest that structures associated with highly concentrated or supersaturated magnesium ions strongly affect the interfacial tension between the NaCl crystal nucleus and the droplet from which it forms. forms a core of