| Summary: | 碩士 === 國立成功大學 === 環境工程研究所 === 83 === Particle size distributions of both PCBs and total-particle
mass witha particle size range between 0.056-100μm, as well as
dry deposition and air sampling were measured at the center of
Tainan city, Taiwan, by using two MOUDI (Micro- Orifice Uniform
Deposite Impactor), one NRI (Noll Rotary Impactor), several dry
deposition plates and several PS-1 (General Metal Work, PS-1)
samplers. The PCB analysis was conducted primarily by using a
gas chromatography (GC) equipped with a 63Ni electron capture
detector (ECD). Particle size distributions (dC/dlogDp v.s. Dp)
of total-PCBs were found to have bimodal size distributions.
The first peak was localized at the particle size range between
5.6 and 10.0μm and the second peak was localized at the
particle size range between 0.31 and 0.52 μm. Four PCB
homologues tetra-, penta-, hexa- and hepta-CBs have higher
concentrations and are dominating the particle size
distribution of total-PCBs. The total-PCB mass dominating in
the coarse particle mode was resulted from the resuspension of
ground dust; while the total- particle mass with a dominating
fine particle mode was due to the particulate emission from
mobile sources, which occurred throughout the condensation
process. More than 83% of both particle-bound total-PCB mass
and total-particle mass were mostly in the particle mode
smaller than 10 μm.
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