Showing papers by "Myoseon Jang published in 1999"

Aerosol formation from the reaction of α-pinene and ozone using a gas- phase kinetics-aerosol partitioning model

Abstract: As a result of new aerosol compositional information, we have implemented an exploratory model for predicting aerosol yields from the reaction of α-pinene with ozone in the atmosphere. This new app...

Partitioning of Semivolatile Organic Compounds in the Presence of a Secondary Organic Aerosol in a Controlled Atmosphere

Abstract: The gas-particle partitioning of select semivolatile organic compounds (SOCs) was studied by injecting the SOCs into a 190 m3 Teflon film chamber containing a secondary organic aerosol (SOA) generated by volatilizing liquid α-pinene into an ozone-concentrated atmosphere. The concentration of total suspended particulates (TSP) and gas and particle-phase SOCs was measured over the course of three experiments spanning a temperature range of 268–297 K and a relative humidity range of 55–100%. An equilibrium partition coefficient, Kp, was calculated for each sampling event. Empirical relationships were then developed to predict the partitioning of the SOCs on the SOA particle source as a function of temperature. Partitioning in this SOA system was compared to that of a SOA generated by the photochemical reaction of NOx with m-xylene. The results indicate that partitioning is similar between the two SOA systems. The effects of multiple particle sources on partitioning was also examined, revealing that a weighted average of predicted Kp values for individual sources can be used to predict partitioning in aerosol mixtures.

A Predictive Model for Adsorptive Gas Partitioning of SOCs on Fine Atmospheric Inorganic Dust Particles

Abstract: The adsorptive gas/particle (G/P) partitioning of semivolatile organic compounds (SOCs) on inorganic Arizona road dust was studied using outdoor Teflon film chambers. Physicochemical parameters from SOC molecular structural information were implemented to describe nonspecific and specific interactions relating to G/P adsorption. Experimental partitioning data were successfully interpreted using physicochemical parameters such as vapor pressure, molecular polarizability, and solute solvation. To evaluate the effect of surface functional groups on the adsorptive G/P partitioning of SOCs, untreated and baked Arizona road dust particles were used. The partitioning coefficients, Kp, for a range of different SOCs on baked dust particles and on untreated dust particles were measured from simultaneous experiments in two outdoor Teflon film chambers that were operated at the same temperature and humidity conditions. Kp values for the two different surface properties of untreated and baked particles were better pre...