Measurements on mass size distribution of roadside aerosols were obtained in downtown Jeju City from July 2018 to May 2020 using an 8-stage cascade impactor sampler and the compositions of aerosols were analyzed. The mass size distribution of total aerosols was bimodal with aerosols existing in both the fine and coarse modes. The mass size distributions of Na+, Mg2+, Ca2+, Cl-, NH4 + and SO4 2- were unimodal, whereas that of K+ was bimodal. For NO3 -, the size distribution in winter and spring was bimodal with the peaks in both fine and coarse modes, whereas for summer and autumn the distribution was unimodal with a peak in the coarse mode. NH4 + was found to co-exist with SO4 2- in the fine mode with an average molar ratio of [NH4 +]/[SO4 2-] equal to 2.05. Good correlation was observed between NO3 - and NH4 + in the fine mode particles in spring and winter. Based on the value of the marine enrichment factor for Cl-, Mg2+, K+, Ca2+ and SO4 2-, it may be inferred that a major part of the roadside aerosols in downtown Jeju City was largely contributed by terrigenous sources, although the influence of sea salt was normally present.

Abstract
1. 서 론
2. 재료 및 방법
    2.1. 측정 지점 및 시료 채취
    2.2. 시료의 분석
    2.3. 농축 계수
3. 결과 및 고찰
    3.1. 도로변 에어로졸의 질량농도
    3.2. 수용성 이온성분의 질량농도
    3.3. 입경별 분포 및 질량중위입경
    3.4. NO3-와 SO42-, NH4+, Na+ 사이의 상관관계
    3.5. 해양의 영향
4. 결 론
REFERENCES

• 이기호(제주대학교 환경공학과) | Ki-Ho Lee (Department of Environmental Engineering, Jeju National University)
• 김수미(제주특별자치도 보건환경연구원 대기환경과) | Su-Mi Kim (Air Environmental Division, Jeju Special Self-Governing Province Research Institute of Health & Environment)
• 허철구(제주대학교 환경공학과) | Chul-Goo Hu (Department of Environmental Engineering, Jeju National University) Corresponding author