Real-Time Measurement of Oligomeric Species in Secondary Organic Aerosol with the Aerosol Time-of-Flight Mass Spectrometer
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- 作者：Deborah S. Gross ; Markus E. Gä ; lli ; Markus Kalberer ; Andre S. H. Prevot ; Josef Dommen ; M. Rami Alfarra ; Jonathan Duplissy ; Kathrin Gaeggeler ; Astrid Gascho ; Axel Metzger ; and Urs Baltensperger
- 刊名：Analytical Chemistry
- 出版年：2006
- 出版时间：April 1, 2006
- 年：2006
- 卷：78
- 期：7
- 页码：2130 - 2137
- 全文大小：668K
- 年卷期：v.78,no.7(April 1, 2006)
- ISSN：1520-6882
文摘
Real-time detection of oligomers in secondary organicaerosols has been carried out with an aerosol time-of-flightmass spectrometer sampling particles generated in asmog chamber. The photooxidation products of 1,3,5-trimethylbenzene and NOx were studied over a range ofinitial 1,3,5-trimethylbenzene concentrations (137-1180ppb), while keeping the 1,3,5-trimethylbenzene to NOxratio nearly constant. The photooxidation products of amixture of 
-pinene (initial concentration 191 ppb),1,3,5-trimethylbenzene (60 ppb), and NOx were alsoinvestigated. In both systems, ions were observed in thesingle-particle mass spectra up to 750 Da; the speciesobserved differed in the two systems. These high-massions occur with characteristic spacing of 14 and 16 Da,indicative of oligomeric species. The results obtainedagree well with off-line (matrix-assisted) laser desorption/ionization mass spectrometry results. The real-time capabilities of the aerosol time-of-flight mass spectrometermake it possible to investigate the temporal developmentof the oligomers with 5-min time resolution and alsodemonstrate that there are certain ions within the oligomer population that occur in nearly all of the particles andwith relatively high signal intensity, suggesting that theseions have higher stability or that the species are formedpreferentially.
-pinene (initial concentration 191 ppb),1,3,5-trimethylbenzene (60 ppb), and NOx were alsoinvestigated. In both systems, ions were observed in thesingle-particle mass spectra up to 750 Da; the speciesobserved differed in the two systems. These high-massions occur with characteristic spacing of 14 and 16 Da,indicative of oligomeric species. The results obtainedagree well with off-line (matrix-assisted) laser desorption/ionization mass spectrometry results. The real-time capabilities of the aerosol time-of-flight mass spectrometermake it possible to investigate the temporal developmentof the oligomers with 5-min time resolution and alsodemonstrate that there are certain ions within the oligomer population that occur in nearly all of the particles andwith relatively high signal intensity, suggesting that theseions have higher stability or that the species are formedpreferentially.