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Applying the silver-tube introduction method for thermal conversion elemental analyses and a new δ 2 H value for NBS 22 oil

Tyler B. Coplen·Haiping Qi
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Abstract

The δ 2 H VSMOW–SLAP value of total hydrogen of the international measurement standard NBS 22 oil was determined by a new method of sealing water in silver tubes for use in a thermal conversion elemental analysis (TC/EA) reduction unit. The isotopic fractionation of water due to evaporation is virtually non-existent in this silver-tube method. A new value for the δ 2 H VSMOW–SLAP of NBS 22 oil, calibrated with isotopic reference waters, was determined to be −116.9 ± 0.8‰ (1σ and n = 31).

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Tyler B. Coplen, Haiping Qi. 2010-07-13. Applying the silver-tube introduction method for thermal conversion elemental analyses and a new δ 2 H value for NBS 22 oil. https://doi.org/10.1002/rcm.4638

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USGS2026

Reaffirming the consistency of the original stock of NBS 19 limestone and its byproduct with finer grain size for δ13C and δ18O calibrations—Both distributed internationally

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