Skip to main content
×
×
Home

Ultra-Small Graphitization Reactors for Ultra-Microscale 14C Analysis at the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) Facility

  • Sunita R Shah Walter (a1), Alan R Gagnon (a1), Mark L Roberts (a1), Ann P McNichol (a1), Mary C Lardie Gaylord (a1) and Elizabeth Klein (a1)...
Abstract

In response to the increasing demand for 14C analysis of samples containing less than 25 μg C, ultra-small graphitization reactors with an internal volume of ∼0.8 mL were developed at NOSAMS. For samples containing 6 to 25 μg C, these reactors convert CO2 to graphitic carbon in approximately 30 min. Although we continue to refine reaction conditions to improve yield, the reactors produce graphite targets that are successfully measured by AMS. Graphite targets produced with the ultra-small reactors are measured by using the Cs sputter source on the CFAMS instrument at NOSAMS where beam current was proportional to sample mass. We investigated the contribution of blank carbon from the ultra-small reactors and estimate it to be 0.3 ± 0.1 μg C with an Fm value of 0.43 ± 0.3. We also describe equations for blank correction and propagation of error associated with this correction. With a few exceptions for samples in the range of 6 to 7 μg C, we show that corrected Fm values agree with expected Fm values within uncertainty for samples containing 6–100 μg C.

Copyright
Corresponding author
Corresponding author. Email: shah@fas.harvard.edu.
References
Hide All
Currie, LA, Polach, HA. 1980. Exploratory analysis of the International Radiocarbon Cross-Calibration Data: consensus values and interlaboratory error. Radiocarbon 22(3):933–5.
Drenzek, NJ, Montluçon, DB, Yunker, MB, Macdonald, RW, Eglinton, TI. 2007. Constraints on the origin of sedimentary organic carbon in the Beaufort Sea from coupled molecular 13C and 14C measurements. Marine Chemistry 103(1–2):146–62.
Gagnon, AR, McNichol, AP, Donoghue, JC, Stuart, DR, von Reden, K, NOSAMS. 2000. The NOSAMS sample preparation laboratory in the next millenium: progress after the WOCE program. Nuclear Instruments and Methods in Physics Research B 172(1–4):409–15.
Hua, Q, Jacobsen, GE, Zoppi, U, Lawson, EM, Williams, AA, Smith, AM, McGann, MJ. 2001. Progress in radiocarbon target preparation at the ANTARES AMS Centre. Radiocarbon 43(2A):275–82.
Hua, Q, Zoppi, U, Williams, AA, Smith, AM. 2004. Small-mass AMS radiocarbon analysis at ANTARES. Nuclear Instruments and Methods in Physics Research B 223–224:284–92.
Ingalls, AE, Shah, SR, Hansman, RL, Aluwihare, LI, Santos, GM, Druffel, ERM, Pearson, A. 2006. Quantifying archaeal community autotrophy in the mesopelagic ocean using natural radiocarbon. Proceedings of the National Academy of Sciences USA 103(17):6442–7.
Ingalls, AE, Ellis, EE, Santos, GM, McDuffee, KE, Truxal, L, Keil, RG, Druffel, ERM. 2010. HPLC purification of higher plant-dervied lignin phenols for compound specific radiocarbon analysis. Analytical Chemistry 82(21):8931–8.
Keigwin, LD, Gagnon, AR. 2015. Comparison of large and ultra-small Δ14C measurements in core top benthic foraminifera from the Okhotsk Sea. Radiocarbon 57(1):123–8.
Keigwin, LD, Guilderson, TP. 2009. Bioturbation artifacts in zero-age sediments. Paleoceanography 24(4):PA4212, doi:10.1029/2008PA001727.
Kirner, DL, Taylor, RE, Southon, JR. 1995. Reduction in backgrounds of microsamples for AMS 14C dating. Radiocarbon 37(2):697704.
Kitagawa, H, Masuzawa, T, Makamura, T, Matsumoto, E. 1993. A batch preparation method for graphite targets with low background for AMS 14C measurements. Radiocarbon 35(2):295300.
Le Clercq, M, van der Plicht, J, Gröning, M. 1998. New 14C reference materials with activities of 15 and 50 pMC. Radiocarbon 40(1):295–7.
Liebl, J, Ortiz, RA, Golser, R, Handle, F, Kutschera, W, Steier, P, Wild, EM. 2010. Studies on the preparation of small 14C samples with an RGA and 13C-enriched material. Radiocarbon 52(3):1394–404.
Liebl, J, Steier, P, Golser, R, Kutschera, W, Mair, K, Priller, A, Vonderhaid, I, Wild, EM. 2013. Carbon background and ionization yield of an AMS system during 14C measurements of microgram-size graphite samples. Nuclear Instruments and Methods in Physics Research B 294:335–9.
Mann, WB. 1983. An international reference material for radiocarbon dating. Radiocarbon 25(2):519–27.
McNichol, AP, Gagnon, AR, Jones, GA, Osborne, EA. 1992. Illumination of a black box: analysis of gas composition during graphite target preparation. Radiocarbon 34(3):321–9.
Ohkouchi, N, Eglinton, TI, Keigwin, LD, Hayes, JM. 2002. Spatial and temporal offsets between proxy records in a sediment drift. Science 298(5596):1224–7.
Ohkouchi, N, Xu, L, Reddy, CM, Montluçon, D, Eglinton, TI. 2005. Radiocarbon dating of alkenones from marine sediments: I. isolation protocol. Radiocarbon 47(3):401412.
Osborne, EA, McNichol, AP, Gagnon, AR, Hutton, DL, Jones, GA. 2000. Internal and external checks in the NOSAMS sample preparation laboratory for target quality and homogeneity. Nuclear Instruments and Methods in Physics Research B 92(1–4):158–61.
Pearson, A, McNichol, AP, Schneider, RJ, von Reden, KF. 1998. Microscale AMS 14C measurement at NOSAMS. Radiocarbon 40(1):6175.
Pearson, A, Seewald, JS, Eglinton, TI. 2005. Bacterial incorporation of relict carbon in the hydrothermal environment of Guaymas Basin. Geochimica et Cosmochimica Acta 69(23):5477–86.
Roberts, ML, Burton, JR, Elder, KL, Longworth, BE, McIntyre, CP, von Reden, KF, Han, BX, Rosenheim, BE, Jenkins, WJ, Galutschek, E, McNichol, AP. 2010. A high-performance 14C accelerator mass spectrometry system. Radiocarbon 52(2):228–35.
Rosenheim, BE, Galy, V. 2012. Direct measurement of riverine particulate organic carbon age structure. Geophysical Research Letters 39:L198703, doi:10.1029/2012GL052883.
Rosenheim, BE, Day, MB, Domack, E, Schrum, H, Benthien, A, Hayes, JM. 2008. Antarctic sediment chronology by programmed-temperature pyrolysis: methodology and data treatment. Geochemistry, Geophysics, Geosystems 9:Q04005, doi:10.1029/2007GC001816.
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):506–19.
Santos, GM, Southon, JR, Griffin, S, Beaupré, SR, Druffel, ERM. 2007. Ultra small-mass AMS 14C sample preparation and analyses at KCCAMS/UCI Facility. Nuclear Instruments and Methods in Physics Research B 259(1):293302.
Santos, GM, Southon, JR, Drenzek, NJ, Ziolkowski, LA, Druffel, ERM, Xu, X, Zhang, D, Trumbore, S, Eglinton, TI, Hughen, KA. 2010. Blank assessment for ultra-small radiocarbon samples: chemical extraction and separation versus AMS. Radiocarbon 52(3):1322–35.
Scott, EM. 2003. The Third International Radiocarbon Intercomparison (TIRI) and the Fourth International Radiocarbon Intercomparison (FIRI): Section 10. Radiocarbon 45(2):285–90.
Shah, SR, Pearson, A. 2007. Ultra-microscale (5–25 μg C) analysis of individual lipids by 14C AMS: assessment and correction for sample processing blanks. Radiocarbon 49(1):6982.
Stuiver, M. 1983. International agreements and the use of the new oxalic acid standard. Radiocarbon 25(2):793–5.
Stuiver, M, Polach, HA. 1977. Discussion: reporting of 14C data. Radiocarbon 19(3):355–63.
van der Borg, K, Alderliesten, C, de Jong, AFM, van den Brink, A, de Haas, AP, Kersemaekers, HJH, Raaymakers, JEMJ. 1997. Precision and mass fractionation in 14C analysis with AMS. Nuclear Instruments and Methods in Physics Research B 123(1–4):97101.
Verkouteren, RM, Klinedinst, DB, Currie, LA. 1997. Iron-manganese system for preparation of radiocarbon AMS targets: characterization of precedural chemical-isotopic blanks and fractionation. Radiocarbon 39(3):269–83.
Vogel, JS, Nelson, DE, Southon, JR. 1987. 14C background levels in an accelerator mass spectrometry system. Radiocarbon 29(3):323–33.
von Reden, KF, McNichol, AP, Pearson, A, Schneider, RJ. 1998. 14C AMS measurements of <100 μg samples with a high-current system. Radiocarbon 40(1):247–53.
Xu, X, Trumbore, SE, Zheng, S, Southon, JR, McDuffee, KE, Luttgen, M, Liu, JC. 2007. Modifying a sealed tube zinc reduction method for preparation of AMS graphite targests: reducing background and attaining high precision. Nuclear Instruments and Methods in Physics Research B 259(1):320–9.
Yokoyama, Y, Koizumi, M, Matsuzaki, H, Miyairi, Y, Ohkouchi, N. 2010. Developing ultra small-scale radiocarbon sample measurement at the University of Tokyo. Radiocarbon 52(2):310–8.
Ziolkowski, LA, Druffel, ERM. 2009. Quantification of extraneous carbon during compound specific radiocarbon analysis of black carbon. Analytical Chemistry 81(24):10, 156–61.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Radiocarbon
  • ISSN: 0033-8222
  • EISSN: 1945-5755
  • URL: /core/journals/radiocarbon
Please enter your name
Please enter a valid email address
Who would you like to send this to? *
×

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed