TY - JOUR A1 - Linsinger, T. A1 - Andrzejuk, W. A1 - Bau, A. A1 - Charoud-Got, J. A1 - De VOs, P. A1 - Emteborg, H. A1 - Hearn, R. A1 - Lamberty, A. A1 - Oostra, A. A1 - Pritzkow, Wolfgang A1 - Quétel, C. A1 - Roebben, G. A1 - Tresl, I. A1 - Vogl, Jochen A1 - Wood, S. T1 - Production of three certified reference materials for the sulfur content in gasoline (petrol) N2 - Directive 2003/17/EC of the European Parliament and the European Council stipulates that petrol (gasoline) with a total sulfur content below 10 mg kg-1 must be available in all European Union member states by 2009. Three certified reference materials were produced in support of this directive in a joint effort of the members of the European Reference Materials Initiative (ERM). Two of the materials were made from commercial petrol, while the third one was prepared from a blend of commercial petrols. Relative between-ampule heterogeneity of the materials was quantified and found to be below 2.5%. Potential degradation during storage and dispatch was quantified, and shelf lives based on these values were set. The three materials were characterized by three institutes using different variants of isotope-dilution mass spectrometry. The results from the three institutes were combined, and the final uncertainties of the respective sulfur mass fractions were estimated including contributions from heterogeneity, stability, and characterization. The following mass fractions were derived: ERM-EF211, 48.8 ± 1.7 mg kg-1; ERM-EF212, 20.2 ± 1.1 mg kg-1; and ERM-EF213, 9.1 ± 0.8 mg kg-1. KW - CRM KW - IDMS KW - ERM PY - 2007 U6 - https://doi.org/10.1021/ef070155t SN - 0887-0624 SN - 1520-5029 VL - 21 IS - 4 SP - 2240 EP - 2244 PB - ACS Publ. CY - Washington, DC AN - OPUS4-16371 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Westwood, S. A1 - Josephs, R. A1 - Daireaux, A. A1 - Wielgosz, R. A1 - Davies, S. A1 - Wang, H. A1 - Rodrigues, J. A1 - Wollinger, W. A1 - Windust, A. A1 - Kang, M. A1 - Fuhai, S. A1 - Philipp, Rosemarie A1 - Kuhlich, Paul A1 - Wong, S.-K. A1 - Shimizu, Y. A1 - Pérez, M. A1 - Avila, M. A1 - Fernandes-Whaley, M. A1 - Prevoo, D. A1 - de Vos, J. A1 - Visser, R. A1 - Archer, M. A1 - LeGoff, T. A1 - Wood, S. A1 - Bearden, D. A1 - Bedner, M. A1 - Boroujerdi, A. A1 - Duewer, D. A1 - Hancock, D. A1 - Lang, B. A1 - Porter, B. A1 - Schantz, M. A1 - Sieber, J. A1 - White, E. A1 - Wise, S. A. T1 - Final report on key comparison CCQM-K55.a (estradiol): an international comparison of mass fraction purity assignment of estradiol N2 - Under the auspices of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) a key comparison, CCQM K55.a, was coordinated by the Bureau International des Poids et Mesures (BIPM) in 2009/2010. Eleven national measurement institutes and the BIPM participated. Participants were required to assign the mass fraction of estradiol present as the main component in the comparison sample (CCQM-K55.a) which consisted of a bulk estradiol hemihydrate material obtained from a commercial supplier that had been extensively but not exhaustively dried prior to sub-division into the units supplied for the comparison. Estradiol was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of organic compounds of medium structural complexity [molar mass range 300–500 Da] and low polarity (pKOW < -2) for which related structure impurities can be quantified by capillary gas phase chromatography (GC) or by high performance liquid chromatography (LC). The majority of participants used a mass balance approach to determine the estradiol content. The key comparison reference value (KCRV) for estradiol in CCQM-K55.a was assigned by combination of KCRVs assigned by consensus from participant results for each orthogonal impurity class. This allowed participants to demonstrate the efficacy (or otherwise) of their implementation of the mass balance approach and to demonstrate that their assigned value for the main component agreed with the KCRV through use of internally consistent contributing methods. The KCRV for the estradiol content of the material was 984.3 mg/g with a combined standard uncertainty of 0.42 mg/g. The individual participant results showed that a relative expanded uncertainty for the purity assignment of 0.2% is a reasonable estimate of the best achievable result by an individual laboratory for a material of this complexity available in this amount at this level of purity. The relative expanded uncertainties reported by laboratories having results consistent with the KCRV ranged from 0.2% to 0.8%. The review of results that were biased from the KCRV showed that two major analytical challenges are posed by the material: the measurement of its water content and controlling for related substance artefact formation during the analysis process. The results displaying a positive bias relative to the KCRV (overestimation of estradiol content) were due to underestimation of the water content of the material, while those with a negative bias (underestimation of estradiol) overestimated the total related substance impurities through a failure to detect and control for artefact formation arising from in situ oxidative dimerization of estradiol in neutral solution prior to analysis. There was however good agreement between all participants in the identification and the quantification of the individual related structure impurities actually present in the sample. The comparison also demonstrated the utility of high-field 1H NMR for both quantitative and qualitative analysis of high purity compounds. It is noted that all the participants who used qNMR as a major or contributing technique and included it as part of, combined it or confirmed it with a conventional 'mass balance' data estimate, obtained results consistent with the KCRV. PY - 2012 U6 - https://doi.org/10.1088/0026-1394/49/1A/08009 SN - 0026-1394 SN - 1681-7575 VL - 49 IS - 1A Tech. Suppl. / 08009 SP - 1 EP - 33 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-26411 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Westwood, S. A1 - Josephs, R. A1 - Daireaux, A. A1 - Wielgosz, R. A1 - Davies, S. A1 - Kang, M. A1 - Ting, H. A1 - Philipp, Rosemarie A1 - Malz, Frank A1 - Shimizu, Y. A1 - Frias, E. A1 - Pérez, M. A1 - Apps, P. A1 - Fernandes-Whaley, M. A1 - De Vos, B. A1 - Wiagnon, K. A1 - Ruangrittinon, N. A1 - Wood, S. A1 - Duewer, D.L. A1 - Schantz, M.M. A1 - Bedner, M. A1 - Hancock, D. A1 - Esker, J. T1 - An international comparison of mass fraction purity assignment of theophylline: CCQM pilot study CCQM-P20.e (Theophylline) PY - 2009 U6 - https://doi.org/10.1088/0026-1394/46/1A/08019 SN - 0026-1394 SN - 1681-7575 VL - 46 IS - 08019 SP - 1 EP - 37 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-20030 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Andrzejuk, W. A1 - Bau, A. A1 - Charoud-Got, J. A1 - de Vos, P. A1 - Emteborg, H. A1 - Lamberty, A. A1 - Linsinger, T. A1 - Oostra, A. A1 - Quetel, C. A1 - Roebben, G. A1 - Tresl, I. A1 - Hearn, R. A1 - Wood, S. A1 - Pritzkow, W. A1 - Vogl, Jochen T1 - Certification of the sulfur mass fraction in three commercial petrol materials - Certified reference materials ERM-EF211, ERM-EF212 and ERM-EF213 N2 - Three petrol reference materials were certified for their total sulfur content in support of Directive 2003/17/EC of the European Parliament and of the European Council, which stipulates that petrol with a maximum S content of 10 mg/kg must be available in all member states by 2009. Commercially available petrol was obtained and filled into borosilicate ampoules without further treatment. Homogeneity of the materials was tested and no heterogeneity was detected for two of the materials, whereas minor heterogeneity was observed for the third material. Stability of the materials was tested for 8-12 months at 60 °C and no degradation was observed. Characterisation was based on isotope-dilution mass spectrometry (IDMS) applied as primary method of measurement by three European metrology institutes and certified values were assigned using all results. The certified uncertainties include contributions of (potential) heterogeneity, potential degradation as well as characterisation. The final assigned values are: ERM-EF211: 48.8 ± 1.7 mg/kg ERM-EF212: 20.2 ± 1.1 mg/kg ERM-EF213: 9.1 ± 0.8 mg/kg The materials are available from IRMM (ERM-EF211), LGC (ERM-EF212) and BAM (ERMEF213) KW - Sulfur KW - Petrol KW - IDMS PY - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-355804 SN - 978-92-79-05370-2 SN - 1018-5593 SP - 1 EP - 37 PB - European Communities CY - Luxembourg AN - OPUS4-35580 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -