Evaluation of 1047-nm Photoacoustic Instruments and Photoelectric Aerosol Sensors in Source-Sampling of Black Carbon Aerosol and Particle-Bound PAHs from Gasoline and Diesel Powered Vehicles
详细信息 查看全文
- 作者：W. P. Arnott ; B. Zielinska ; C. F. Rogers ; J. Sagebiel ; Kihong Park ; Judith Chow ; Hans Moosmü ; ller ; John G. Watson ; K. Kelly ; D. Wagner ; A. Sarofim ; J. Lighty ; and G. Palmer
- 刊名：Environmental Science & Technology
- 出版年：2005
- 出版时间：July 15, 2005
- 年：2005
- 卷：39
- 期：14
- 页码：5398 - 5406
- 全文大小：279K
- 年卷期：v.39,no.14(July 15, 2005)
- ISSN：1520-5851
文摘
A series of measurements have been performed at HillAir Force Base to evaluate real-time instruments formeasurements of black carbon aerosol and particle-bound PAHs emitted from spark and ignition compressionvehicles. Vehicles were operated at idle or fast idle inone set of measurements and were placed under load ona dynamometer during the second series. Photoacousticinstruments were developed that operated at a wavelengthof 1047 nm where gaseous interference is negligible,although sensitivity to black carbon is good. Compact,efficient, solid-state lasers with direct electronic modulationcapabilities are used in these instruments. Black carbonmeasurements are compared with samples collected on quartzfiber filters that were evaluated using the thermal opticalreflectance method. A measure of total particle-boundPAH was provided by photoelectric aerosol sensors (PAS)and is evaluated against a sum of PAH mass concentrationsobtained with a filter-denuder combination. The PAS had tobe operated with a dilution system held at approximately150 
C for most of the source sampling to prevent spuriousbehavior, thus perhaps compromising detection of lighterPAHs. PA and PAS measurements were found to have a highdegree of correlation, perhaps suggesting that the PAScan respond to the polycyclic nature of the black carbonaerosol. The PAS to PA ratio for ambient air in Fresno,CA is 3.7 times as large in winter than in summer months,suggesting that the PAS clearly does respond tocompounds other than BC when the instrument is usedwithout the heated inlet.
C for most of the source sampling to prevent spuriousbehavior, thus perhaps compromising detection of lighterPAHs. PA and PAS measurements were found to have a highdegree of correlation, perhaps suggesting that the PAScan respond to the polycyclic nature of the black carbonaerosol. The PAS to PA ratio for ambient air in Fresno,CA is 3.7 times as large in winter than in summer months,suggesting that the PAS clearly does respond tocompounds other than BC when the instrument is usedwithout the heated inlet.