Hostname: page-component-7c8c6479df-r7xzm Total loading time: 0 Render date: 2024-03-29T12:20:23.477Z Has data issue: false hasContentIssue false

A Continuous-Flow Gas Interface of a Thermal/Optical Analyzer With 14C AMS for Source Apportionment of Atmospheric Aerosols

Published online by Cambridge University Press:  07 November 2016

Konstantinos Agrios
Affiliation:
Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland Laboratory of Radiochemistry, Paul Scherrer Institute (PSI), Villigen, Switzerland
Gary Salazar*
Affiliation:
Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
Sönke Szidat
Affiliation:
Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
*
*Corresponding author. Email: gary.salazar@dcb.unibe.ch.

Abstract

This article reports on the performance of a continuous-flow interface for CO2 gas feeding into the ion source of a 200-kV accelerator mass spectrometer (AMS) in splitless mode. Distinct CO2 fractions and subfractions produced by a commercial Sunset OC/EC (organic carbon/elemental carbon) analyzer from ambient atmospheric aerosols filters are injected into the source and then analyzed by their 14C/12C ratio in real time. New features are revealed from organic aerosol subfractions, which thermally desorb close to each other and are only visible by real-time analysis. An optimized setup for this purpose is presented for the measurement of CO2 amounts from 3 to 45 μg C. Efficiencies of 4.5–8.0% for the formation of C- ions from CO2 are obtained for sample masses of 5–10 μg C and carbon mass flow rates below 2 µg min–1. However, this ionization efficiency is substantially suppressed at high carbon mass flow rates. The potential of this method for a refined apportionment of aerosol sources is demonstrated with ambient filter samples.

Type
Advances in Physical Measurement Techniques
Copyright
© 2016 by the Arizona Board of Regents on behalf of the University of Arizona 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Selected Papers from the 2015 Radiocarbon Conference, Dakar, Senegal, 16–20 November 2015

References

REFERENCES

Agrios, K, Salazar, G, Zhang, YL, Uglietti, C, Battaglia, M, Luginbühl, M. 2015. Online coupling of pure O2 thermo-optical methods – 14C AMS for source apportionment of carbonaceous aerosols. Nuclear Instruments and Methods in Physics Research B 361:288293.Google Scholar
Currie, LA, Kessler, JD. 2005. On the isolation of elemental carbon (EC) for micro-molar 14C accelerator mass spectrometry: development of a hybrid reference material for 14C–EC accuracy assurance, and a critical evaluation of the thermal optical kinetic (TOK) EC isolation procedure. Atmospheric Chemistry and Physics 5:28332845.Google Scholar
De Gouw, J, Jimenez, L. 2009. Organic aerosols in the Earth’s atmosphere. Environmental Scientific Technology 43:76147618.Google Scholar
Fahrni, SM, Wacker, L, Synal, H-A, Szidat, S. 2013. Improving a gas ion source for 14C AMS. Nuclear Instruments and Methods in Physics Research B 294:320327.Google Scholar
Hodzic, A, Jimenez, JL, Prévôt, ASH, Szidat, S, Fast, JD, Madronich, S. 2010. Can 3-D models explain the observed fractions of fossil and non-fossil carbon in and near Mexico City? Atmospheric Chemistry and Physics 10(22):10,9971016.Google Scholar
Kanakidou, M, Seinfeld, JH, Pandis, SN, Barnes, I, Dentener, FJ, Facchini, MC, Van Dingenen, R, Ervens, B, Nenes, A, Nielsen, CJ, Swietlick, E, Putaud, JP, Balkanski, Y, Fuzzi, S, Horth, J, Moortgat, GK, Winterhalter, R, Myhre, CEL, Tsigaridis, K, Vignati, E, Stephanou, EG, Wilson, J. 2005. Organic aerosol and global climate modelling: a review. Atmospheric Chemistry and Physics 5:10531123.CrossRefGoogle Scholar
Le Clercq, M, van der Plicht, J, Gröning, M. 1998. New 14C reference materials with activities of 15 and 50 pMC. Radiocarbon 40(1):295297.Google Scholar
Perron, N, Szidat, S, Fahrni, S, Ruff, M, Wacker, L, Prévôt, ASH, Baltensperger, U. 2010. Towards on-line 14C analysis of carbonaceous aerosol fractions. Radiocarbon 52(2–3):761768.Google Scholar
Pöschl, U. 2005. Atmospheric aerosols: composition, transformation, climate and health effects. Angewandte Chemie International Edition 44(46):75207540.CrossRefGoogle ScholarPubMed
Reimer, P, Brown, TA, Reimer, R. 2004. Discussion: reporting and calibration of post-bomb 14C data. Radiocarbon 46(3):12991304.Google Scholar
Robinson, AL, Donahue, NM, Shrivastava, MK, Weitkamp, EA, Sage, AM, Grieshop, AP, Lane, TE, Pierce, R, Pandis, SN. 2007. Rethinking organic aerosols: semi-volatile emissions and photochemical aging. Science 315(5816):12591262.Google Scholar
Rozanski, K, Stichler, W, Gonfiantini, R, Scott, EM, Beukens, RP, Kromer, B, van der Plicht, J. 1992. The IAEA 14C Intercomparison Exercise 1990. Radiocarbon 34(3):506519.Google Scholar
Ruff, M, Fahrni, SM, Gäggeler, HW, Hajdas, I, Suter, M, Synal, H-A, Szidat, S, Wacker, L. 2010. Online radiocarbon measurements of small samples using elemental analyzer and MICADAS gas ion source. Radiocarbon 52(4):16451656.Google Scholar
Salazar, G, Zhang, YL, Agrios, K, Szidat, S. 2015. Development of a method for fast and automatic radiocarbon measurement of aerosol samples by online coupling of an elemental analyzer with a MICADAS AMS. Nuclear Instruments and Methods in Physics Research B 361:163167.Google Scholar
Salazar, G, Agrios, K, Eichler, R, Szidat, S. 2016. Characterization of the axial jet separator with a CO2/helium mixture: toward GC-AMS hyphenation. Analytical Chemistry 88:16471653.Google Scholar
Szidat, S. 2009. Sources of Asian haze. Science 323(5913):470471.CrossRefGoogle ScholarPubMed
Szidat, S, Jenk, TM, Gäggeler, HW, Synal, H-A, Fisseha, R, Baltensperger, U, Kalberer, M, Samburova, V, Reimann, S, Kasper-Giebl, A, Hajdas, I. 2004a. Radiocarbon (14C)-deduced biogenic and anthropogenic contributions to organic carbon (OC) of urban aerosols from Zürich, Switzerland. Atmospheric Environment 38(24):40354044.Google Scholar
Szidat, S, Jenk, TM, Gäggeler, HW, Synal, H-A, Hajdas, I, Bonani, G, Saurer, M. 2004b. THEODORE, a two-step heating system for the EC/OC determination of radiocarbon (14C) in the environment. Nuclear Instruments and Methods in Physics Research B 223–224:829836.Google Scholar
Szidat, S, Jenk, TM, Synal, H-A, Kalberer, M, Wacker, L, Hajdas, I, Kasper-Giebl, A, Baltensperger, U. 2006. Contributions of fossil fuel, biomass-burning, and biogenic emissions to carbonaceous aerosols in Zurich as traced by 14C. Journal of Geophysical Research 111(D7):D07206.Google Scholar
Szidat, S, Salazar, G, Vogel, E, Battaglia, M, Wacker, L, Synal, H-A, Türler, A. 2014. 14C analysis and sample preparation at the new Bern Laboratory for the Analysis of Radiocarbon with AMS (LARA). Radiocarbon 56(2):561566.CrossRefGoogle Scholar
Wacker, L, Fahrni, SM, Hajdas, I, Molnar, M, Synal, H-A, Szidat, S, Zhang, YL. 2013. A versatile gas interface for routine radiocarbon analysis with a gas ion source. Nuclear Instruments and Methods in Physics Research B 294:315319.Google Scholar
Zhang, YL, Perron, N, Ciobanu, VG, Zotter, P, Minguillon, MC, Wacker, L, Prevot, ASH, Baltensperger, U, Szidat, S. 2012. On the isolation of OC and EC and the optimal strategy of radiocarbon-based source apportionment of carbonaceous aerosols. Atmospheric Chemistry and Physics 12(22):1084110856.Google Scholar
Zotter, P, Ciobanu, VG, Zhang, YL, El-Haddad, I, Macchia, M, Daellenbach, KR, Salazar, GA, Huang, RJ, Wacker, L, Hueglin, C, Piazzalunga, A, Fermo, P, Schwikowski, M, Baltensperger, U, Szidat, S, Prévôt, ASH. 2014a. Diurnal cycle of fossil and nonfossil carbon using radiocarbon analyses during CalNex. Journal of Geophysical Research: Atmospheres 119:68186835.Google Scholar
Zotter, P, Ciobanu, VG, Zhang, YL, El-Haddad, I, Macchia, M, Daellenbach, KR, Salazar, G, Huang, RJ, Wacker, L, Hueglin, C, Piazzalunga, A, Fermo, P, Schwikowski, M, Baltensperger, U, Szidat, S, Prévôt, ASH. 2014b. Radiocarbon analysis of elemental and organic carbon in Switzerland during winter-smog episodes from 2008 to 2012 – Part 1: source apportionment and spatial variability. Atmospheric Chemistry and Physics 14(13):551570.Google Scholar