TY - JOUR A1 - Kipphardt, Heinrich A1 - Matschat, Ralf A1 - Vogl, Jochen A1 - Gusarova, Tamara A1 - Czerwensky, Michael A1 - Heinrich, Hans-Joachim A1 - Hioki, A. A1 - Konopelko, L.A. A1 - Methven, B. A1 - Miura, T. A1 - Petersen, O. A1 - Riebe, Gundel A1 - Sturgeon, R. A1 - Turk, G.C. A1 - Yu, L. L. T1 - Purity determination as needed for the realisation of primary standards for elemental determination: status of international comparability N2 - Within the National Metrology Institutes (NMIs) and designated laboratories, an interlaboratory comparison, CCQM-P107, was conducted to verify the degree of international comparability concerning the results of purity analysis. The mass fractions of Ag, Bi, Cd, Cr, Ni, Tl at the lower mg/kg-level in a high purity zinc material were determined, but the real measurand in metrological sense was the sum of the six mass fractions. Homogeneity was investigated by glow discharge mass spectrometry, reference values were obtained using isotope dilution mass spectrometry. Six NMIs participated, contributing eight independent data sets. The agreement amongst the results of the participants, their median and the agreement with the reference values were usually excellent and in almost all cases below the target uncertainty of 30% relative. In this manner, the accuracy of results and the comparability between the participants was demonstrated to be established. KW - Interlaboratory comparison KW - Purity analysis KW - High purity metals KW - CCQM-P107 KW - Zinc PY - 2010 U6 - https://doi.org/10.1007/s00769-009-0557-0 SN - 0949-1775 SN - 1432-0517 VL - 15 IS - 1 SP - 29 EP - 37 PB - Springer CY - Berlin AN - OPUS4-20767 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogl, Jochen A1 - Kipphardt, Heinrich A1 - del Rocío Arvizu Torres, M. A1 - Manzano, J.V.L. A1 - Rodrigues, J.M. A1 - de Sena, R.C. A1 - Yim, Y.-H. A1 - Heo, S.W. A1 - Zhou, T. A1 - Turk, G.C. A1 - Winchester, M. A1 - Yu, L. L. A1 - Miura, T. A1 - Methven, B. A1 - Sturgeon, R. A1 - Jährling, R. A1 - Rienitz, O. A1 - Tunc, M. A1 - Can, S.Z. T1 - Final report of the key comparison CCQM-K72: Purity of zinc with respect to six defined metallic analytes N2 - KEY COMPARISON High purity elements can serve as a realization of the SI unit amount of substance for the specific element. Solutions prepared from high purity metals by applying gravimetric preparation and the concept of molar mass are used as 'calibration' solutions in many fields of analytical chemistry and provide the metrological basis in elemental analysis. Since ideal purity does not exist for real materials, the actual purity of the high purity material must be known with a specified uncertainty. As required uncertainties around 10-4 relative on the purity statement are not accessible in almost all cases by a direct measurement of the element in itself, the indirect approach is followed, where all elements excepting the matrix element itself are measured and their sum is subtracted from the value for ideal purity, which is 1 kg/kg. It was the aim of this comparison to demonstrate the capability of national metrology institutes and designated institutes to determine the purity of pure elements. In order to limit the effort within this comparison, only six metallic impurities (Ag, Al, Cd, Cr, Ni, Tl) in the low mg/kg range are considered in a zinc matrix. It has to be underlined here that the task was to measure the purity of zinc based on the determination of six analytes. The task is not trace analysis of specific analytes in zinc. This subtle distinction defines different measurands. The sample, pure Zn, was cut in pieces of cubic geometry for wet chemical analysis or of pin geometry for GDMS analysis and was sent to the participants. The comparison was run under the auspices of the Inorganic analysis Working Group (IAWG) of the CCQM and was piloted by the BAM Federal Institute for Materials Research and Testing, Berlin, Germany. The majority of the participants applied ICP-MS techniques and only two participants used additionally atomic absorption spectrometry. GDMS was used only by one participant. The observed spreads for the measurement results reported by the participants were significantly lower than those of the preceding study CCQM-P107 and were well below the target uncertainty of 30% relative. As a consequence, comparability within the participating laboratories is demonstrated to be established. The individual measurement results, mean values and medians derived were in all cases very consistent with the reference values obtained by IDMS and so the accuracy of the measurement results for the participating laboratories is as well demonstrated to be established. Especially with the results of CCQM-P62 and CCQM-P107 in mind, the outcome of CCQM-K72 can be considered as a big step forward in the community. CCQM is aware of the difference between a characterization based on only six analytes and a complete characterization. Therefore, the pilot study CCQM-P149 has been initiated and already started, which focuses on the fit-for-purpose approaches for the purity determination of metals (here: zinc) to be used as primary standards in elemental analysis. Another follow-up in the form of a pilot study on non-metal impurities is mandatory, because non-metal impurities such as oxygen, nitrogen and sulfur often make up the largest contributions. 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 (CIPM MRA). KW - CCQM KW - Metrology KW - Purity PY - 2014 U6 - https://doi.org/10.1088/0026-1394/51/1A/08008 SN - 0026-1394 SN - 1681-7575 VL - 51 IS - 1A (Tech.Suppl. 2014) SP - 08008, 1 EP - 40 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-30772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rienitz, O. A1 - Schiel, D. A1 - Görlitz, V. A1 - Jährling, R. A1 - Vogl, Jochen A1 - Lara-Manzano, J.V. A1 - Zon, A. A1 - Fung, W.-H. A1 - Buzoianu, M. A1 - De Sena, R.C. A1 - Dos Reis, L.A. A1 - Valiente, L. A1 - Yim, Y.-H. A1 - Hill, S. A1 - Champion, R. A1 - Fisicaro, P. A1 - Bing, W. A1 - Turk, G.C. A1 - Winchester, M. R. A1 - Saxby, D. A1 - Merrick, J. A1 - Hioki, A. A1 - Miura, T. A1 - Suzuki, T. A1 - Linsky, M. A1 - Barzev, A. A1 - Máriássy, M. A1 - Cankur, O. A1 - Ari, B. A1 - Tunc, M. A1 - Konopelko, L.A. A1 - Kustikov, Y.A. A1 - Bezruchko, M. T1 - Final report on CCQM-K87: Mono-elemental calibration solutions N2 - The aim of this comparison was to demonstrate the capability of national metrology institutes to measure elemental mass fractions at a level of w(E) ≈ 1 g/kg as found in almost all mono-elemental calibration solutions. These calibration solutions represent an important link in traceability systems in inorganic analysis. Virtually all traceable routine measurements are linked to the SI through these calibration solutions. Every participant was provided with three solutions of each of the three selected elements chromium, cobalt and lead. This comparison was a joint activity of the Inorganic Analysis Working Group (IAWG) and the Electrochemical Analysis Working Group (EAWG) of the CCQM and was piloted by the Physikalisch-Technische Bundesanstalt (PTB, Braunschweig, Germany) with the help of the Bundesanstalt für Materialforschung und -prüfung (BAM, Berlin, Germany), the Centro Nacional de Metrología (CENAM, Querétaro, Mexico) and the National Institute of Standards and Technology (NIST, Gaithersburg, USA). A small majority of participants applied inductively coupled plasma optical emission spectrometry (ICP OES) in combination with a variety of calibration strategies (one-point-calibration, bracketing, calibration curve, each with and without an internal standard). But also IDMS techniques were carried out on quadrupole, high resolution and multicollector ICP-MS machines as well as a TIMS machine. Several participants applied titrimetry. FAAS as well as ICP-MS combined with non-IDMS calibration strategies were used by at least one participant. The key comparison reference values (KCRV) were agreed upon during the IAWG/EAWG meeting in November 2011 held in Sydney as the added element content calculated from the gravimetric sample preparation. Accordingly the degrees of equivalence were calculated. Despite the large variety of methods applied no superior method could be identified. The relative deviation of the median of the participants' results from the gravimetric reference value was equal or smaller than 0.1% (with an average of 0.05%) in the case of all three elements. KW - CCQM KW - Metrology KW - IDMS PY - 2012 U6 - https://doi.org/10.1088/0026-1394/49/1A/08010 SN - 0026-1394 SN - 1681-7575 VL - 49 IS - 08010, 1A (Technical Supplement 2012) SP - 1 EP - 104 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-30458 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -