TY - JOUR A1 - Nieuwenkamp, G. A1 - Wessel, R. M. A1 - van der Veen, A.M.H. A1 - Ziel, P. R. A1 - Han, Q. A1 - Tuma, Dirk A1 - Woo, J.-C. A1 - Fuko, J.T. A1 - Szilágyi, N. A1 - Büki, T. A1 - Konopelko, L. A1 - Kustikov, Y.A. A1 - Popova, T.A. A1 - Pankratov, V.V. A1 - Pir, M.N. A1 - Nazarov, E.V. A1 - Ehvalov, L.V. A1 - Timofeev, A.U. A1 - Kuzmina, T.A. A1 - Meshkov, A.V. A1 - Valková, M. A1 - Pätoprsty, V. A1 - Downey, M. A1 - Vargha, G. A1 - Brown, A. A1 - Milton, M. T1 - International comparison CCQM-K77: Refinery gas N2 - Refinery gas is a complex mixture of hydrocarbons and non-combustible gases (e.g., carbon monoxide, carbon dioxide, nitrogen, helium). It is obtained as part of the refining and conversion of crude oil. This key comparison aims to evaluate the measurement capabilities for these types of mixtures. The results of the key comparison indicate that the analysis of a refinery-type gas mixture is for some laboratories a challenge. Overall, four laboratories (VSL, NIM, NPL and VNIIM) have satisfactory results. The results of some participants highlight some non-trivial issues, such as appropriate separation between saturated and unsaturated hydrocarbons, and issues with the measurement of nitrogen, hydrogen and helium. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA). DatesIssue 1A (Technical Supplement 2012) KW - Ringversuch KW - Raffineriegas KW - Chromatographische Analyse PY - 2012 U6 - https://doi.org/10.1088/0026-1394/49/1A/08003 SN - 0026-1394 SN - 1681-7575 VL - 49 IS - 08003 SP - 1 EP - 71 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-25931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Flores, E. A1 - Idrees, F. A1 - Moussay, P. A1 - Viallon, J. A1 - Wielgosz, R. A1 - Fernández, T. A1 - Ramírez, S. A1 - Rojo, A. A1 - Shinji, U. A1 - Waldén, J. A1 - Sega, M. A1 - Sang-Hyub, O. A1 - Macé, T. A1 - Couret, C. A1 - Qiao, H. A1 - Smeulders, D. A1 - Guenther, F.R. A1 - Thorn, W.J. III A1 - Tshilongo, J. A1 - Ntsasa, N.G. A1 - Stovcík, V. A1 - Valková, M. A1 - Konopelko, L. A1 - Gromova, E. A1 - Nieuwenkamp, G. A1 - Wessel, R. M. A1 - Milton, M. A1 - Harling, A. A1 - Vargha, G. A1 - Tuma, Dirk A1 - Kohl, Anka A1 - Schulz, Gert T1 - Final report on international comparison CCQM-K74: Nitrogen dioxide, 10 µmol/mol N2 - There is a high international priority attached to activities which reduce NOx in the atmosphere. The current level of permitted emissions is typically between 50 µmol/mol and 100 µmol/mol, but lower values are expected in the future. Currently, ambient air quality monitoring regulations also require the measurement of NOx mole fractions as low as 0.2 µmol/mol. The production of accurate standards at these levels of mole fractions requires either dilution of a stable higher concentration gas standard or production by a dynamic technique, for example one based on permeation tubes. The CCQM-K74 key comparison was designed to evaluate the level of comparability of National Metrology Institutes' measurement capabilities and standards for nitrogen dioxide (NO2) at a nominal mole fraction of 10 µmol/mol. The measurements of this key comparison took place from June 2009 to May 2010. Seventeen laboratories took part in this comparison coordinated by the BIPM and VSL. The key comparison reference value was based on BIPM measurement results, and the standard measurement uncertainty of the reference value was 0.042 µmol/mol. This key comparison demonstrated that the results of the majority of the participants agreed within limits of ±3% relative to the reference value. The results of only one laboratory lay significantly outside these limits. Likewise this comparison made clear that a full interpretation of the results of the comparison needed to take into account the presence of nitric acid (in the range 100 nmol/mol to 350 nmol/mol) in the cylinders circulated as part of the comparison, as well as the possible presence of nitric acid in the primary standards used by participating laboratories. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA). DatesIssue 1A (Technical Supplement 2012) KW - Ringversuch KW - NO2 KW - Spurenverunreinigungen KW - Meßverfahren PY - 2012 U6 - https://doi.org/10.1088/0026-1394/49/1A/08005 SN - 0026-1394 SN - 1681-7575 VL - 49 IS - 08005 SP - 1 EP - 117 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-25927 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Paul, Andrea A1 - Bräuer, Bastian A1 - Nieuwenkamp, G. A1 - Ent, H. A1 - Bremser, Wolfram T1 - A validated near-infrared spectroscopic method for methanol detection in biodiesel N2 - Abstract. Biodiesel quality control is a relevant issue as biodiesel properties influence diesel engine performance and integrity. Within the European Metrology Research Program (EMRP) ENG09 project “Metrology for Biofuels”, an on-line /at-site suitable near-infrared spectroscopy (NIRS) method has been developed in parallel with an improved EN14110 headspace GC analysis method for methanol in biodiesel. Both methods have been optimized for a methanol content of 0.2 mass% as this represents the maximum limit of methanol content in FAME according to EN 14214:2009. The NIRS method is based on a mobile NIR spectrometer equipped with a fiber-optic coupled probe. Due to the high volatility of methanol, a tailored air-tight adaptor was constructed to prevent methanol evaporation during measurement. The methanol content of biodiesel was determined from evaluation of NIRS spectra by Partial Least Squares Regression (PLS). Both GC analysis and NIRS exhibited a significant dependence on biodiesel feedstock. The NIRS method is applicable to a content range of 0.1 % (m/m) to 0.4 % (m/m) of methanol with uncertainties at around 6% relative for the different feedstocks. A direct comparison of headspace GC and NIRS for samples of FAMEs yielded that the results of both methods are fully compatible within their stated uncertainties. KW - FAME KW - Headspace GC KW - NIR KW - PLSR KW - EMRP PY - 2016 U6 - https://doi.org/10.1088/0957-0233/27/6/065002 SN - 0957-0233 SN - 1361-6501 VL - 27 IS - 6 SP - 065002, 1 EP - 9 PB - IOP Publishing Ltd CY - UK AN - OPUS4-37471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -