Nuclear Science and Techniques

《核技术》(英文版) ISSN 1001-8042 CN 31-1559/TL     2019 Impact factor 1.556

Nuclear Science and Techniques ›› 2014, Vol. 25 ›› Issue (2): 020303 doi: 10.13538/j.1001-8042/nst.25.020303

• NUCLEAR CHEMISTRY,RADIOCHEMISTRY,RADIOPHARMACEUTICALS AND NUCLEAR MEDICINE • Previous Articles     Next Articles

Evaluation on nitrogen isotopes analysis in high-C/N-ratio plants using elemental analyzer/isotope ratio mass spectrometry

HU Jing, LIU Wei-Guo   

  1. 1State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075, China
    2Xi’an Jiaotong University, Xi’an 710049, China
  • Contact: LIU Wei-Guo E-mail:liuwg@loess.llqg.ac.cn
HU Jing, LIU Wei-Guo. Evaluation on nitrogen isotopes analysis in high-C/N-ratio plants using elemental analyzer/isotope ratio mass spectrometry.Nuclear Science and Techniques, 2014, 25(2): 020303     doi: 10.13538/j.1001-8042/nst.25.020303

Abstract:

Elemental analyzer/isotope ratio mass spectrometry (EA/IRMS) has been widely applied to analyze the 15N/14N isotope composition (15N) of plants and soils, but the 15N results may be inaccurate due to incomplete combustion of the high-C/N-ratio plant samples by EA. Therefore, it is necessary to develop a method to solve the problem of imperfect combustion. In this study, with we used two methods: 1) adding copper oxide powder to the samples, and 2) increasing the O2 flow (from 100mL/min to 200mL/min) for the auto sampler inlet purge line of the EA. The 15N values of the plant samples became more positive and tended to be stable after complete combustion. Also, the required blank samples for each plant sample decreased with increasing amount of the added CuO powder. However, at 200mL/min of the oxygen flow in the EA, complete combustion could not be achieved without adding copper oxide, but this was done with decreased amount of CuO powder. Therefore, mixing cupric oxide into the high-C/N-ratio samples was an efficient, simple and convenient way to solve the problem of imperfect combustion in the EA.

Key words: Nitrogen isotopes, Cupric oxide, O2 flow of EA/IRMS, High-C/N-ratio plants, EA/IRMS