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This study explores the effects of an Asian dust storm (ADS) and Southeast Asian biomass burning on the composition of atmospheric aerosols in the coastal area of southern Taiwan in spring 2010. Coarse and fine particles were collected using two manual dichotomous samplers (Dichots) that were equipped with Teflon and Quartz filters. The results reveal that the concentrations of PM 10 and PM 2.5 in the ADS period were about twice those before and after this. More than half of water-soluble ions in coarse particles (PM 2.5-10 ) were Cl -and Na + (sea salt), while 70% of water-soluble ions of fine particles were SO 4 2-and NH 4 + (secondary aerosols). The OC/EC ratios of PM 2.5 and PM 2.5-10 were all above 2.0. Over 98% of the metals in coarse and fine particles were crustal elements (98.1-99.1%), and over 60% of the metals in PM 10 were in coarse particles (PM 2.5-10 ). The water-soluble ion, EC, OC, and metal contents in PM 2.5 all exceeded those in PM 2.5-10 . The ADS was associated with higher concentrations of water-soluble ions in PM 2.5 and PM 2.5-10 than was the non-ADS period, except for K + in PM 2.5-10 . ADS most increased the Ca 2+ content and concentration, causing a rise in the average concentrations of Ca 2+ in coarse and fine particles by factors of 3.0 and 3.2, respectively. In the ADS period, although the OC and EC concentrations of coarse and fine particles increased, the OC and EC contents in these particles decreased. The ADS period was associated with higher metal contents in coarse and fine particles than the non-ADS period, and the increase in PM 2.5-10 (more than 2%) exceeded that in PM 2.5 . In PM 2.5-10 and PM 2.5 , the Ca and Ni contents increased the most, respectively. In addition, the concentrations of the water-soluble ions, EC, OC, and metals in PM 2.5-10 and PM 2.5 increased, but their contents decreased, while the contents of the other constituents (= total -(water-soluble ions + EC + OC + metals)) in PM 2.5-10 and PM 2.5 increased. It is also found that Southeast Asian biomass burning is related to the deterioration of the air quality of southern Taiwan.

The emission and distribution of polychlorinated debenzo-p-dioxins/dibenzofurans (PCDD/Fs) was investigated in two municipal solid waste incinerators (MSWIs) and one coal-fired power plant (PP) in southern Taiwan. Samples were collected from stack flue gases (SFG), bottom residues (BR), super heater (SH), economizer (EC), semi-dry absorber (SDA), bag filter (BF), and fly ash pit (FAP) in MSWIs. Stack flue gases, bottom residues and electrostatic dust collectors (ESD) in PP were also collected. In order to compare the difference between the results of MSWIs and PP, samples from SFG, BS, and FAP in a PP were also determined. Seventeen congeners of PCDD/Fs were analyzed by utilizing a highresolution gas chromatograph/high-resolution mass spectrometer (HRGC/HRMS). Distributions of total PCDD/F-I-TEQ in each unit of MSWI-A and MSWI-B were SFG (0.3%, 0.07%), BR (3.9%, 0.62%), SH (0.17%, 0.24%), EC (4.2%, 0.05%), SDA (1.29%, 7.06%), and BF (90.14%, 91.97%), respectively. However, those in SFG, BS, and FAP of PP were 99.58%, 0.17%, and 0.25%, respectively. The above results indicated 99.5% PCDD/Fs were trapped in the fly ash of MWSI. On the other hand, 99.7% PCDD/Fs was emitted to the atmosphere from PP. The results of this study provide useful information for controlling PCDD/Fs in MSWIs and PP.

A comprehensive model 10 predict the lead aerosol size distribution for typical incinerator operating conditions has been developed. Using the feed rate and incinerator operating conditions, the metal transfer rate to the gas phase is determined using a mass transfer calculation. A detailed, multicomponent aerosol dynamic model is developed accounting for the chemical kinetics and applied to a lead-oxygenchlorine system. Reasonable agreement is obtained between model predictions and experimental data from controlled studies for different aspects of the model. The effect of chlorine on the resulting aerosol size distribution has been determined. The role of the transfer rates of lead to the gas phase on the resulting size distributions have also been determined. Simulations have been performed for typical conditions encountered in a waste incinerator.