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NSVECNitrogen Gas Gas   15N

NSVEC is N2 gas sealed in glass ampules (about 7 ml), to be used for δ15N calibration purposes.

NSVEC is a pure tank gas and was originally prepared by G. Junk and H. J. Svec, Iowa State University, USA [1]; C. Kendall, U.S. Geological Survey then split the sample into several hundred aliquots [2]. The δ15N value of this reference material is the result of the statistical evaluation of an interlaboratory comparison [3].

(R/I/C) Classification assigned to the property value for analyte (Recommended/Information/Certified)

References:

1. JUNK, G., SVEC, H.J., The absolute abundance of the nitrogen isotopes in the atmosphere and compressed gas from various sources, Geochim. Cosmochim. Acta 14 (1958) 234-243

2. KENDALL, C., GRIM, E., Combustion tube method for measurement of nitrogen isotope ratios using calcium oxide for total removal of carbon dioxide and water, Anal. Chem. 62 (1990) 526-529.

3. B?HLKE, J.K., COPLEN, T.B., Interlaboratory comparison of reference materials for nitrogen isotope ratio measurements. Proceedings of a consultants meeting held in Vienna, 1 - 3. Dec. 1993, IAEA-TECDOC-825, IAEA, Vienna, Austria (1995) 51-66.