Step Change in Improving the Accuracy of Nitrous Oxide Reference Materials for Underpinning Atmospheric Composition Measurements.
Anal Chem
; 95(34): 12867-12874, 2023 Aug 29.
Article
em En
| MEDLINE
| ID: mdl-37581365
ABSTRACT
We have employed a new approach to quantify the amount fraction of nitrous oxide in a synthetic air matrix gas used to prepare high-accuracy reference materials of the same component. Until now, this was the largest contributor to the measurement uncertainty of nitrous oxide in air reference materials at atmospheric amount fractions (â¼330 nmol mol-1), as identified in a recent international comparison. A novel preconcentration method has resulted in a measurement of 363 pmol mol-1 of nitrous oxide in a synthetic air matrix gas with an expanded uncertainty of 27 pmol mol-1. This represents a significant breakthrough as using these developments with an optimized dilution hierarchy (to minimize the gravimetric uncertainty) promises to result in SI traceable reference materials with expanded uncertainties as low as 0.032% relative (k = 2). This supports the World Meteorological Organization-Global Atmosphere Watch network compatibility goal for underpinning atmospheric observations.
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MEDLINE
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En
Ano de publicação:
2023
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Article