DOI: 10.1016/j.atmosenv.2015.06.053
Scopus记录号: 2-s2.0-84937439268
论文题名: Modeling and analysis of sampling artifacts in measurements of gas-particle partitioning of semivolatile organic contaminants using filter-sorbent samplers
作者: Wang X ; , Bi C ; , Xu Y
刊名: Atmospheric Environment
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2015
卷: 117 起始页码: 99
结束页码: 109
语种: 英语
英文关键词: Air sampling
; Gas/particle partitioning
; Modeling
; Sampling artifacts
; Semivolatile organic compounds (SVOCs)
Scopus关键词: Gases
; Hydrostatic pressure
; Ionization of gases
; Models
; Organic compounds
; Particle size
; Sorbents
; Sorption
; Air sampling
; Distribution of particles
; Gas/particle partitioning
; Mechanistic modeling
; Partition coefficient
; Sampling artifacts
; Semi-volatile organic compounds (SVOCs)
; Semi-volatile organic contaminants
; Air filters
; polychlorinated dibenzodioxin
; polychlorinated dibenzofuran
; polycyclic aromatic hydrocarbon
; semivolatile organic compound
; sorbent
; unclassified drug
; volatile organic compound
; air sampling
; error analysis
; filter
; gas phase reaction
; organic pollutant
; particle size
; size distribution
; sorption
; volatile organic compound
; air filter
; air sampling
; Article
; artifact
; gas
; priority journal
; sampling bias
; validation process
; vapor pressure
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: Measurements of gas/particle partition coefficients for semivolatile organic compounds (SVOCs) using filter-sorbent samplers can be biased if a fraction of gas-phase mass is measured erroneously as particle-phase due to sorption of SVOC gases to the filter, or, if a fraction of particle-phase mass is measured erroneously as gas-phase due to penetration of particles into the sorbent. A fundamental mechanistic model to characterize the air sampling process with filter-sorbent samplers for SVOCs was developed and partially validated. The potential sampling artifacts associated with measurements of gas-particle partitioning were examined for 19 SVOCs. Positive sampling bias (i.e., overestimation of gas/particle partition coefficients) was observed for almost all the SVOCs. For certain compounds, the measured partition coefficient was several orders of magnitude greater than the presumed value. It was found that the sampling artifacts can be ignored when the value of log[Kf /(Kp {dot operator}Cp,a )] is less than 7. By normalizing the model, general factors that influence the sampling artifacts were investigated. Correlations were obtained between the dimensionless time required for the gas-phase SVOCs within the filter to reach steady state (Ts,s*) and the chemical Vp values, which can be used to estimate appropriate sampling time. The potential errors between measured and actual gas/particle partition coefficients of SVOCs as a function of sampling velocity and time were calculated and plotted for a range of SVOCs (vapor pressures: 10-8 10-3 Pa). These plots were useful in identifying bias from the sampling in previously-completed field measurements. Penetration of particles into the sorbent may result in significant underestimation of the partition coefficient for particles in the size range between 10 nm and 2 μm. For most of the selected compounds, backup filters can be used to correct artifacts effectively. However, for some compounds with very low vapor pressure, the artifacts remained or became even larger than they were without the backup filter. Thus, the option of backup filters must be considered carefully in field measurements of the gas/particle partitioning of SVOCs. The results of this work will allow researchers to predict potential artifacts associated with SVOC gas/particle partitioning as functions of compounds, the concentration of particles, the distribution of particle sizes, sampling velocity, and sampling time. © 2015 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/81582
Appears in Collections: 气候变化事实与影响
There are no files associated with this item.
作者单位: School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, China; Department of Civil, Architectural and Environmental Engineering, The University of Texas at AustinTX, United States
Recommended Citation:
Wang X,, Bi C,, Xu Y. Modeling and analysis of sampling artifacts in measurements of gas-particle partitioning of semivolatile organic contaminants using filter-sorbent samplers[J]. Atmospheric Environment,2015-01-01,117