In:
Radiocarbon, Cambridge University Press (CUP), Vol. 55, No. 2 ( 2013), p. 421-425
Abstract:
At the Seoul National University accelerator mass spectrometry (AMS) laboratory, we are planning to develop an automated sample preparation system for higher throughput of radiocarbon dating. This system will consist of several sections, including a combustion line, CO 2 trap, graphitization system, and so on. We usually collect CO 2 by cryogenic trapping. However, since handling liquid nitrogen is expected to be rather difficult, we are interested in replacing the cryogenic method with the molecular sieve method for the collection of CO 2 . In this study, we compare the performance of the cryogenic trapping method and molecular sieve method. Zeolite 13X is used as a molecular sieve, and as test samples we use the oxalic acid standard (NIST SRM 4990C), high-purity graphite powder, and archaeological charcoals. The pMC values and the radiocarbon ages (BP) obtained from samples prepared by the above 2 methods are very similar. We especially focused on the memory effect of the molecular sieve, meaning the CO 2 contamination from a previous sample, which can cause errors in age determination. To reduce this effect, we flowed He gas through a zeolite container for several minutes at a high temperature before the CO 2 was introduced. By the adding this step, we have obtained more reliable results.
Type of Medium:
Online Resource
ISSN:
0033-8222
,
1945-5755
DOI:
10.1017/S0033822200057556
Language:
English
Publisher:
Cambridge University Press (CUP)
Publication Date:
2013
detail.hit.zdb_id:
2028560-7
SSG:
11
SSG:
13
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