Dokument-ID Dokumenttyp Autoren/innen Persönliche Herausgeber/innen Haupttitel Abstract Auflage Verlagsort Verlag Herausgeber (Institution) Erscheinungsjahr Titel des übergeordneten Werkes Jahrgang/Band ISBN Veranstaltung Veranstaltungsort Beginndatum der Veranstaltung Enddatum der Veranstaltung Ausgabe/Heft Erste Seite Letzte Seite URN DOI Lizenz Datum der Freischaltung OPUS4-26831 Zeitschriftenartikel Westwood, S.; Josephs, R.; Choteau, T.; Daireaux, A.; Mesquida, C.; Wielgosz, R.; Rosso, A.; de Arechavaleta, M.R.; Davies, S.; Wang, H.; do Rego, E.C.P.; Rodrigues, J.M.; de Freitas Guimaraes, E.; Sousa, M.V.B.; Monteiro, T.M.; das Neves Valente, L.A.; Violante, F.G.M.; Almeida, R. R. R.; Quaresma, M.C.B.; Nogueira, R.; Windust, A.; Dai, X.; Li, X.; Zhang, W.; Li, M.; Shao, M.; Wei, C.; Wong, S.-K.; Cabillic, J.; Gantois, F.; Philipp, Rosemarie; Pfeifer, Dietmar; Hein, Sebastian; Klyk-Seitz, Urszula-Anna; Ishikawa, K.; Castro, E.; Gonzalez, N.; Krylov, A.; Lin, T.T.; Kooi, L.T.; Fernandes-Whaley, M.; Prévoo, D.; Archer, M.; Visser, R.; Nlhapo, N.; de Vos, B.; Ahn, S.; Pookrod, P.; Wiangnon, K.; Sudsiri, N.; Muaksang, K.; Cherdchu, C.; Gören, A.C.; Bilsel, M.; LeGoff, T.; Bearden, D.; Bedner, M.; Duewer, D.; Hancock, D.; Lang, B.; Lippa, K.; Schantz, M.; Sieber, j. Final report on key comparison CCQM-K55.b (aldrin): An international comparison of mass friction purity assignment of aldrin 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.b, was coordinated by the Bureau International des Poids et Mesures (BIPM) in 2010/2011. Nineteen national measurement institutes and the BIPM participated. Participants were required to assign the mass fraction of aldrin present as the main component in the comparison sample for CCQM-K55.b which consisted of technical grade aldrin obtained from the National Measurement Institute Australia that had been subject to serial recrystallization and drying prior to sub-division into the units supplied for the comparison. Aldrin 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 Da to 500 Da] and low polarity (pKOW < -2) for which related structure impurities can be quantified by capillary gas phase chromatography (GC). The key comparison reference value (KCRV) for the aldrin content of the material was 950.8 mg/g with a combined standard uncertainty of 0.85 mg/g. The KCRV was assigned by combination of KCRVs assigned by consensus from participant results for each orthogonal impurity class. The relative expanded uncertainties reported by laboratories having results consistent with the KCRV ranged from 0.3% to 0.6% using a mass balance approach and 0.5% to 1% using a qNMR method. The major analytical challenge posed by the material proved to be the detection and quantification of a significant amount of oligomeric organic material within the sample and most participants relying on a mass balance approach displayed a positive bias relative to the KCRV (overestimation of aldrin content) in excess of 10 mg/g due to not having adequate procedures in place to detect and quantify the non-volatile content-specifically the non-volatile organics content-of the comparison sample. There was in general excellent agreement between participants in the identification and the quantification of the total and individual related structure impurities, water content and the residual solvent content of the sample. The comparison demonstrated the utility of 1H NMR as an independent method for quantitative analysis of high purity compounds. In discussion of the participant results it was noted that while several had access to qNMR estimates for the aldrin content that were inconsistent with their mass balance determination they decided to accept the mass balance result and assumed a hidden bias in their NMR data. By contrast, laboratories that placed greater confidence in their qNMR result were able to resolve the discrepancy through additional studies that provided evidence of the presence of non-volatile organic impurity at the requisite level to bring their mass balance and qNMR estimates into agreement. Bristol Inst. of Physics Publ. 2012 Metrologia 49 CCQM-K55.b Final Report October 2012 1 41 10.1088/0026-1394/49/1A/08014 2016-02-19 OPUS4-54188 Zeitschriftenartikel Westwood, S.; Martos, G.; Josephs, R.; Choteau, T.; Wielgosz, R.; Davies, S.; Moawad, M.; Tarrant, G.; Chan, B.; Alamgir, M.; de Rego, E.; Wollinger, W.; Garrido, B.; Fernandes, J.; de Sena, R.; Oliveira, R.; Melanson, J.; Bates, J.; Mai Le, P.; Meija, J.; Quan, C.; Huang, T.; Zhang, W.; Ma, R.; Zhang, S.; Hao, Y.; He, Y.; Song, S.; Wang, H.; Su, F.; Zhang, T.; Li, H.; Lam, W.; Wong, W.; Fung, W.; Philipp, Rosemarie; Dorgerloh, Ute; Meyer, Klas; Piechotta, Christian; Riedel, Juliane; Westphalen, Tanja; Giannikopoulou, P.; Alexopoulos, Ch.; Kakoulides, E.; Kitamaki, Y.; Yamazaki, T.; Shimizu, Y.; Kuroe, M.; Numata, M.; Pérez-Castorena, A.; Balderas-Escamilla, M.; Garcia-Escalante, J.; Krylov, A.; Mikheeva, A.; Beliakov, M.; Palagina, M.; Tkachenko, I.; Spirin, S.; Smirnov, V.; Tang Lin, T.; Pui Sze, C.; Juan, W.; Lingkai, W.; Ting, L.; Quinde, L.; Yizhao, C.; Lay Peng, S.; Fernandes-Whaley, M.; Prevoo-Franzsen, D.; Quinn, L.; Nhlapo, N.; Mkhize, D.; Marajh, D.; Chamane, S.; Ahn, S.; Choi, K.; Lee, S.; Han, J.; Baek, S.; Kim, B.; Marbumrung, S.; Jongmesuk, P.; Shearman, K.; Boonyakong, C.; Bilsel, M.; Gündüz, S.; Ün, I.; Yilmaz, H.; Bilsel, G.; Gökçen, T.; Clarkson, C.; Warren, J.; Achtar, E. Mass fraction assignment of Bisphenol-A high purity material The CCQM-K148.a comparison was coordinated by the BIPM on behalf of the CCQM Organic Analysis Working Group for NMIs and DIs which provide measurement services in organic analysis under the CIPM MRA. It was undertaken as a "Track A" comparison within the OAWG strategic plan. CCQM-K148.a demonstrates capabilities for assigning the mass fraction content of a solid organic compound having moderate molecular complexity, where the compound has a molar mass in the range (75 - 500) g/mol and is non-polar (pKow < −2), when present as the primary organic component in a neat organic solid and where the mass fraction content of the primary component in the material is in excess of 950 mg/g. Participants were required to report the mass fraction of Bisphenol A present in one supplied unit of the comparison material. Participants using a mass balance method for the assignment were also required to report their assignments of the impurity components present in the material. Methods used by the seventeen participating NMIs or DIs were predominantly based on either stand-alone mass balance (summation of impurities) or qNMR approaches, or the combination of data obtained using both methods. The results obtained using thermal methods based on freezing-point depression methods were also reported by a limited number of participants. There was excellent agreement between assignments obtained using all three approaches to assign the BPA content. The assignment of the values for the mass fraction content of BPA consistent with the KCRV was achieved by most of the comparison participants with an associated relative standard uncertainty in the assigned value in the range (0.1 - 0.5)%. IOP Publishing Bureau International des Poids et Mesures (BIPM) 2021 Metrologia 58 1A 08015 10.1088/0026-1394/58/1A/08015 2022-01-05 OPUS4-31072 Zeitschriftenartikel Westwood, S.; Josephs, R.; Choteau, T.; Daireaux, A.; Wielgosz, R.; Davies, S.; Moad, M.; Chan, B.; Munoz, A.; Conneely, P.; Ricci, M.; Do Rego, E.C.P.; Garrido, B.C.; Violante, F.G.M.; Windust, A.; Dai, X.; Huang, T.; Zhang, W.; Su, F.; Quan, C.; Wang, H.; Lo, M.; Wong, W.; Gantois, F.; Lalerle, B.; Dorgerloh, Ute; Koch, Matthias; Klyk-Seitz, Urszula-Anna; Pfeifer, Dietmar; Philipp, Rosemarie; Piechotta, Christian; Recknagel, Sebastian; Rothe, Robert; Yamazaki, T.; Zakaria, O. B.; Castro, E.; Balderas, M.; González, N.; Salazar, C.; Regalado, L.; Valle, E.; Rodríguez, L.; Laguna, L.Á..; Ramírez, P.; Avila, M.; Ibarra, J.; Valle, L.; Arce, M.; Mitani, Y.; Konopelko, L.; Krylov, A.; Lopushanskaya, E.; Lin, T.T.; Liu, Q.; Kooi, L.T.; Fernandes-Whaley, M.; Prevoo-Franzsen, D.; Nhlapo, N.; Visser, R.; Kim, B.; Lee, H.; Kankaew, P.; Pookrod, P.; Sudsiri, N.; Shearman, K.; Gören, A.C.; Bilsel, G.; Yilmaz, H.; Bilsel, M.; Cergel, M.; Coskun, F.G.; Uysal, E.; Gündüz, S.; Ün, I.; Warren, J.; Bearden, D.W.; Bedner, M.; Duewer, D.L.; Lang, B.E.; Lippa, K.A.; Schantz, M.M.; Sieber, J.R. Final report on key comparison CCQM-K55.c (L-(+)-Valine): Characterization of organic substances for chemical purity KEY COMPARISON 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.c, was coordinated by the Bureau International des Poids et Mesures (BIPM) in 2012. Twenty National Measurement Institutes or Designated Institutes and the BIPM participated. Participants were required to assign the mass fraction of valine present as the main component in the comparison sample for CCQM-K55.c. The comparison samples were prepared from analytical grade L-valine purchased from a commercial supplier and used as provided without further treatment or purification. Valine was selected to be representative of the performance of a laboratory's measurement capability for the purity assignment of organic compounds of low structural complexity [molecular weight range 100–300] and high polarity (pKOW > -2). The KCRV for the valine content of the material was 992.0 mg/g with a combined standard uncertainty of 0.3 mg/g. The key comparison reference value (KCRV) was assigned by combination of KCRVs assigned from participant results for each orthogonal impurity class. The relative expanded uncertainties reported by laboratories having results consistent with the KCRV ranged from 1 mg/g to 6 mg/g when using mass balance based approaches alone, 2 mg/g to 7 mg/g using quantitative 1H NMR (qNMR) based approaches and from 1 mg/g to 2.5 mg/g when a result obtained by a mass balance method was combined with a separate qNMR result. The material provided several analytical challenges. In addition to the need to identify and quantify various related amino acid impurities including leucine, isoleucine, alanine and a-amino butyrate, care was required to select appropriate conditions for performing Karl Fischer titration assay for water content to avoid bias due to in situ formation of water by self-condensation under the assay conditions. It also proved to be a challenging compound for purity assignment by qNMR techniques. There was overall excellent agreement between participants in the identification and the quantification of the total and individual related structure impurities, water content, residual solvent and total non-volatile content of the sample. Appropriate technical justifications were developed to rationalise observed discrepancies in the limited cases where methodology differences led to inconsistent results. The comparison demonstrated that to perform a qNMR purity assignment the selection of appropriate parameters and an understanding of their potential influence on the assigned value is critical for reliable implementation of the method, particularly when one or more of the peaks to be quantified consist of complex multiplet signals. Bristol Inst. of Physics Publ. 2014 Metrologia 51 08010, 1 44 10.1088/0026-1394/51/1A/08010 2016-02-20 OPUS4-44999 Zeitschriftenartikel Westwood, S.; Josephs, R.; Choteau, T.; Daireaux, A.; Stoppacher, N.; Wielgosz, R.; Davies, S.; do Rego, E.; Wollinger, W.; Garrido, B.; Fernandes, J.; Lima, J.; Oliveira, R.; de Sena, R.; Windust, A.; Huang, T.; Dai, X.; Quan, C.; He, H.; Zhang, W.; Wei, C.; Li, N.; Gao, D.; Liu, Z.; Lo, M.; Wong, W.; Pfeifer, Dietmar; Koch, Matthias; Dorgerloh, Ute; Rothe, Robert; Philipp, Rosemarie; Hanari, N.; Rezali, M.; Arzate, C.; Berenice, M.; Caballero, V.; Osuna, M.; Krylov, A.; Kharitonov, S.; Lopushanskaya, E.; Liu, Q.; Lin, T.; Fernandes-Whaley, M.; Quinn, L.; Nhlapo, N.; Prevoo-Franzsen, D.; Archer, M.; Kim, B.; Baek, S.; Lee, S.; Lee, J.; Marbumrung, S.; Kankaew, P.; Chaorenpornpukdee, K.; Chaipet, T.; Shearman, K.; Gören, A.; Gündüz, S.; Yilmaz, H.; Un, I.; Bilsel, G.; Clarkson, C.; Bedner, M.; Camara, J.; Lang, B.; Lippa, K.; Nelson, M.; Toman, B.; Yu, L. Mass fraction assignment of folic acid in a high purity material - CCQM-K55.d (Folic acid) Final Report The comparison required the assignment of the mass fraction of folic acid present as the main component in the comparison sample. Performance in the comparison is representative of a laboratory's measurement capability for the purity assignment of organic compounds of medium structural complexity [molecular weight range 300-500] and high polarity (pKOW < −2). Methods used by the eighteen participating NMIs or DIs were based on a mass balance (summation of impurities) or qNMR approach, or the combination of data obtained using both methods. The qNMR results tended to give slightly lower values for the content of folic acid, albeit with larger associated uncertainties, compared with the results obtained by mass balance procedures. Possible reasons for this divergence are discussed in the report, without reaching a definitive conclusion as to their origin. The comparison demonstrates that for a structurally complex polar organic compound containing a high water content and presenting a number of additional analytical challenges, the assignment of the mass fraction content property value of the main component can reasonably be achieved with an associated relative standard uncertainty in the assigned value of 0.5% Institute of Physics Publishing (IOP) ; Bureau International des Poids et Mesures 2018 Metrologia 55 Technical Supplement, 2018 08013, 1 38 10.1088/0026-1394/55/1A/08013 2018-05-24