Konopelko L.A.,Dimendeleyev Institute For Metrology Vniim |
Kustikov Y.A.,Dimendeleyev Institute For Metrology Vniim |
Kolobova A.V.,Dimendeleyev Institute For Metrology Vniim |
Shor N.B.,Dimendeleyev Institute For Metrology Vniim |
And 14 more authors.
Metrologia | Year: 2014
A new COOMET project no 483/RU/09 Supplementary comparison of primary standard gas mixtures: Nitrogen monoxide in Nitrogen (50 μ mol/mol), was registered in the KCDB BIPM as COOMET.QM-S1. The gas mixtures for the comparison were prepared gravimetrically in accordance with the requirements of ISO 6142  and were studied regarding their composition and stability at the coordinating laboratory in accordance with requirements of ISO 6143. The preparation ?f gas mixtures for the comparison was carried out from pure substances by 3 stage dilution. Each mixture had its own slightly different reference value of NO mole fraction on the level of 50μmol/mol. 7 gas mixtures were prepared in cylinders and 6 of them were chosen as traveling standards. The pressure of mixtures in the cylinders was approximately 100 bar. The measurement protocol requested each laboratory to perform at least 3 measurements obtained under repeatability conditions including at least three separate calibrations. The protocol informed the participants about the nominal concentration. The amount of substance fractions as obtained from gravimetry and purity analysis of the parent substances were used as reference values. Long-term stability measurements did not show any change in the concentration of the target components within accuracy of these measurements, so that there was not any corrections due to instability.