A study of the performance of different acidic aerosol samplers and the characteristics of acidic aerosols in Hsinchu Taiwan

Conference · Thu Jul 01 04:00:00 EDT 1999

OSTI ID:20006508

Tsai, C J; Perng, S B; Chiou, S F; Lin, T Y

An annular denuder system (ADS), a honeycomb denuder system (HDS) and a micro-orifice uniform deposit impactor (MOUDI) were used to investigate the physical and chemical characteristics of acidic aerosols in Hsinchu Taiwan. The performances of different denuder samplers were also compared. The concentrations (in {mu}g/m{sup 3}) of major ionic species: H{sup +}, SO{sub 4}{sup 2{minus}} NO{sub 3}{sup {minus}} and NH{sub 4}{sup +} are found to average 0.019{+-}0.01 (std. dev.) (range: 0.00--0.02), 7.60{+-}5.08 (range: 1.37--16.54), 7.67{+-}5.50 (range: 1.18--21.58) and 5.27{+-}2.90 (range: 1.14--9.42), as measured by the ADS, respectively. Aerosol acidity is not severe compared to urban cities in other countries, due to neutralization of aerosol acidity by ammonia in Hsinchu. The results indicate that the size distributions of H{sup +} and NH{sub 4}{sup +} are in the single mode while those of NO{sub 3}{sup {minus}} and SO{sub 4}{sup 2{minus}} are found to be mainly bimodal. The ions such as SO{sub 4}{sup 2{minus}}, NO{sub 3}{sup {minus}}, NH{sub 4}{sup +} and H{sup +} are dominant in the fine mode, while ions such as Cl{sup {minus}}, Na{sup +} and K{sup +} are found to be in both fine and coarse modes. Comparing two different denuder samplers, the average concentration of HNO{sub 3} measured by the HDS is found to be 40% higher than that of the ADS while the average concentrations of NO{sub 3}{sup {minus}} and Cl{sup {minus}} measured by the ADS are higher than those of the HDS by 12% and 14%, respectively. The concentrations of other species are found to be similar in both denuder samplers.

• Research Organization: National Chiao Tung Univ., Hsinchu (TW)
• OSTI ID: 20006508
• Report Number(s): CONF-990608--
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
AEROSOL MONITORING
AIR POLLUTION
AIR SAMPLERS
NITRATES
NITRIC ACID
PARTICLE SIZE
PERFORMANCE
SULFATES
TAIWAN