| Summary: | 碩士 === 國立中央大學 === 環境工程研究所 === 105 === On-road vehicle emission is an important source of contribution for PM2.5 in urban areas.The negative health effects of exposure to PM2.5 and other Traffic related air pollutants(TRAP) is well confirmed.For city dwekkers and cimuters can be exposed to higher concentrations of vehicle emissions. Ultrafine particles (UFP) and Black carbon (BC) are the typical surrogates for vehicle emissions, and they could vary dramatically in space and time within urban microenvironment. This exhibits great challenges for estimating human exposure and the resulting potential health effects. Conventional stationary monitoring stations/networks are not enough to effectively capture TRAPs spatial characteristics.Mobile monitoring approaches have been conducted to address poorly represented by ambient stationary monitoring.In this study, a mobile real-time monitoring system was established to characterize the on-road vehicle emissions along the selected route in different period and season, including particulate matter(PM2.5), UFP size distributions, lung deposition surface area(LDSA) , Black carbon(BC) and carbon monoxide (CO) in an urban city of northern Taiwan. The results showed that the concentration of particles in the experimental area were significant differences in the season.In the winter rush hour, the particle GMD was about 32.89 ± 6.59 [nm], the number of UFP was about 61228±38320 [#/cm3], PM2.5 was about 23±8 [μg/m3], BC was about 3.93±2.24 [μg/m3], the LDSA was about 229.29±119.99 [μm2/cm3] and the CO was about 2.44±2.07 [ppm], in the summer, the GMD was about 39.53±9.62 [nm], the number of UFP was about 30318±1584 [#/cm3], PM2.5 was about 18±9 [μg/m3], BC was about 3.93±2.24 [μg/m3], the LDSA was about 148.33±87.3 [μm2/cm3] and the CO is about 3.46±2.74 [ppm] on the busy road. PM2.5 variation was not in agreement with the traffic fluxes and no significant difference among 14 points in 2 routes and in the day.The variation of BC between each point was partially related to traffic flux, like P1 and P7 with higher traffic fluxes and BC level.However, the overall average concentration of BC was not affected by rush hour and seasonal variations show that on road BC in study area was relatively stable.The UFP number conc. , LDSA and CO in R1 exceed 2 times higher than R2, in cause of the R1 with higher traffic flux than R2.The UFP NC,LDSA and CO had same trend and were agreement with the traffic flux in each point. Traffic-related pollutants levels not only depend on the traffic flux, but also the local topography, such as road intersection or buildings environment around the street.The LDSA/SA ratio indicated that the particle’s irregular level, the ratio was not significant difference between R1 and R2 no matter summer and winter showed that on road PM’s characteristic was same in all time.The LDSA/SA ratio in summer noon was lowest level and the UFP、LDSA and BC identically had lowest level in all season and period of day. The number and LDSA conc. had significant correlation with all three types of vehicles. Significant correlations were also found for CO and GMD, however, GMD’s R shows a negative value.
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