Title Page
Contents
요약 10
Abstract 13
1. Introduction 15
2. Materials and Methods 18
2.1. Study area 18
2.2. Sample collection and preparation 20
2.3. Elemental and isotopic analyses 22
2.3.1. Elemental analysis 22
2.3.2. Isotope analyses 24
2.4. Statistical analysis 28
3. Results and discussion 29
3.1. Characteristics of elemental composition in PM₂.₅ 29
3.1.1. Comparison of elemental composition in PM₂.₅ 30
3.1.2. Variations in elemental composition of PM₂.₅ 33
3.1.3. Correlation between elemental compositions 39
3.1.4. Principal component analysis of elemental composition 40
3.2. Characteristics of Pb and Sr isotopes in PM₂.₅ 43
3.2.1. Variations of Pb and Sr isotopes 43
3.2.1. Correlations between Pb isotopes and Pb concentration 48
3.2.2. Correlation between Sr isotopes and Sr concentration 50
3.3. Elemental and isotopic characteristics of potential sources 54
3.3.1. Exhaust gas 54
3.3.2. Brake dust 55
3.3.3. Urban and Road dust 55
3.3.4. Power plant dust 56
3.3.5. Incinerator dust of rural and urban areas 57
3.4. Source identification using Pb and Sr isotopes 60
4. Conclusions 66
References 69
Table 1. Elemental concentration and recovery rate of certified reference material (CZ-120, IRMM). 23
Table 2. Comparison of elemental concentrations in PM₂.₅ among different cities (SU, DJ, CC, and BJ represent Seoul, Daejeon, Chuncheon, and Beijing, respectively). 32
Table 3. Elemental concentrations of PM₂.₅ collected at KIST, Seoul during February to March 2021. 35
Table 4. Pearson's correlation of measured elements in PM₂.₅. 41
Table 5. Elemental and isotope geochemistry of Sr and Pb in PM₂.₅ collected at KIST, Seoul during February and March 2021. 44
Table 6. Elemental concentrations of potential sources. 58
Table 7. Elemental and isotope geochemistry of Sr and Pb in potential sources. 59
Figure 1. A map showing sampling sites of potential sources (a) and PM₂.₅ (KIST, Seoul) (b). (Road dust in Deajeon, power plant and incinerator dust (urban) in... 19
Figure 2. Flow chart of sample preparation processes. 21
Figure 3. Flow charts of purification processes for Sr (a) and Pb (b), respectively. 27
Figure 4. Temporal variations of elemental concentrations in PM₂.₅ during February 5th and March 31st, 2021; Al, Ca and Fe (a), Zn, Cr and Cu (b), Ni, Ba...[이미지참조] 38
Figure 5. Component-loading plot for the principal component analysis. PC1 and PC2 account 44.1% and 13.7%, respectively. 42
Figure 6. Variations of Pb isotopes in PM₂.₅ during sampling periods. (Air quality alert: PM₂.₅ concentration of higher 75µg/m³ lasted for more than 2 hours, Aeolian... 46
Figure 7. Variation of ⁸⁷Sr/⁸⁶Sr ratio in PM₂.₅ during sampling periods . (Air quality alert: PM₂.₅ concentration of higher 75µg/m³ lasted for more than 2 hours, Aeolian... 47
Figure 8. Plots of Pb isotopes versus Pb concentration in PM₂.₅; ²⁰⁶Pb/²⁰⁴Pb ratio (a), ²⁰⁷Pb/²⁰⁴Pb ratio (b), and ²⁰⁸Pb/²⁰⁴Pb ratio (c). 49
Figure 9. Plot of ⁸⁷Sr/⁸⁶Sr ratios versus Sr concentration in PM₂.₅. 52
Figure 10. Plot of ⁸⁷Sr/⁸⁶Sr ratios versus Ca/Sr ratios in PM₂.₅ and bedrock. OCR represents old crystalline rocks (e.g. gneisses or granites) from Choi et al. (2023);... 53
Figure 11. Plots of ²⁰⁶Pb/²⁰⁷Pb ratio versus ²⁰⁸Pb/²⁰⁶Pb ratio in PM₂.₅ and potential sources, where DJ, BJ and SU represent Daejeon, Beijing, and Seoul, respectively.... 63
Figure 12. Plot of ⁸⁷Sr/⁸⁶Sr ratios in PM₂.₅ and potential sources, where NC and DJ represent Nanchang and Daejeon, respectively. Soil, construction, road dust, and... 64
Figure 13. Plot of ²⁰⁸Pb/²⁰⁶Pb ratios versus ⁸⁷Sr/⁸⁶Sr ratios in PM₂.₅ and potential sources. BJ represents Beijing. 65