DOI: 10.1016/j.atmosenv.2014.03.023
Scopus记录号: 2-s2.0-84897070248
论文题名: A size-segregation method for monitoring the diurnal characteristics of atmospheric black carbon size distribution at urban traffic sites
作者: Cheng Y ; -H ; , Liao C ; -W ; , Liu Z ; -S ; , Tsai C ; -J ; , Hsi H ; -C
刊名: Atmospheric Environment
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2014
卷: 90 起始页码: 78
结束页码: 86
语种: 英语
英文关键词: Black carbon
; Mass size distribution
; Size segregation
; Taipei urban area
Scopus关键词: Atmospheric aerosols
; Particle size
; Segregation (metallography)
; Size distribution
; Atmospheric samples
; Average concentration
; Black carbon
; Geometric standard deviations
; Mass size distribution
; Particle size spectra
; Size segregation
; Urban areas
; Urban growth
; black carbon
; aerosol
; black carbon
; coagulation
; diurnal variation
; particle size
; pollution monitoring
; size distribution
; traffic emission
; urban area
; urban pollution
; wind velocity
; aerosol
; article
; atmosphere
; bioaccumulation
; chemical parameters
; chemical procedures
; circadian rhythm
; controlled study
; mass size distribution
; particle size
; priority journal
; sampling
; size segregation
; Taiwan
; traffic
; urban area
; velocity
; wind
; Taipei
; Taiwan
Scopus学科分类: Environmental Science: Water Science and Technology
; Earth and Planetary Sciences: Earth-Surface Processes
; Environmental Science: Environmental Chemistry
英文摘要: Understanding the characteristics of the size distribution of ambient black carbon (BC) in distinct environments is critical because the influence of BC aerosols on climate, visibility, and human health depends strongly on the distribution of BC aerosols over the particle size spectrum. In this study, a novel method for determining the mass size distribution of BC in atmospheric aerosols was developed. This size-segregation method relies on measuring BC in parallel using two aethalometers, one of which is used to measure the total BC (BCT) mass concentration as a reference level and the other is used to measure the BC (BCi) mass concentration for BC sizes below specific particle sizes that are selected using a size cut-off inlet. In this study, this method was applied to measure BC in atmospheric samples at an urban traffic site. The aethalometers were operated continually from December 15, 2012 to January 31, 2013, and from February 15, 2013 to March 31, 2013. The measurement results presented in this paper are for the diurnal variation patterns, average concentrations, mass fractions, and size distributions of BC aerosols. The results indicate that BCT mass concentration is approximately 2.8μgm-3 in the Taipei urban area. The levels of BC at this sampling site were affected markedly by traffic emission levels and local wind speed. At the sampling site, the average BC2.5/BCT, BC1.0/BCT, BC0.5/BCT, BC0.25/BCT, and BC0.1/BCT were 0.96±0.04, 0.92±0.07, 0.89±0.04, 0.73±0.10, and 0.18±0.08, respectively. The results indicate that approximately 90% of the BC aerosols were smaller than 0.5μm, that most of the BC aerosols (55%) were in the size range of 0.1-0.25μm, and that approximately 18% of the BC aerosols were ultrafine. Moreover, the daily average mass size distribution of BC exhibited a single accumulation mode at 0.16μm at this sampling site. The mode of the BC mass size distribution at rush hour (9 AM) was only 0.14μm, which is smaller than the daily average. Moreover, the mode of the BC mass size distribution at an early morning hour (3 AM) was 0.18μm, and a minor coarse mode was also observed during this period. The results further revealed that the geometric diameter (Dpg) of the BC aerosols varied between 0.14 and 0.22μm and the geometric standard deviation (σg) of these BC aerosols ranged between 1.4 and 2.3 during the sampling period. Because BC exhibits extremely low chemical reactivity; the size distribution of BC in the atmosphere does not change substantially except through coagulation. © 2014 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/80861
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Safety, Health and Environmental Engineering, Ming Chi University of Technology, 84 Gungjuan Rd, Taishan, New Taipei 24301, Taiwan; Institute of Environmental Engineering, National Chiao Tung University, 1001 University Rd, Hsinchu 30010, Taiwan; Graduate Institute of Environmental Engineering, National Taiwan University, 71 Jhoushan Rd., Daan, Taipei 10673, Taiwan
Recommended Citation:
Cheng Y,-H,, Liao C,et al. A size-segregation method for monitoring the diurnal characteristics of atmospheric black carbon size distribution at urban traffic sites[J]. Atmospheric Environment,2014-01-01,90