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 - Gusarova, Tamara A1 - Methven, B. A1 - Kipphardt, Heinrich A1 - Sturgeon, R. A1 - Matschat, Ralf A1 - Panne, Ulrich T1 - Calibration of double focusing glow discharge mass spectrometry instruments with pin-shaped synthetic standards N2 - Calibration of two commercially available glow discharge double focusing mass spectrometers, the VG 9000 and Element GD, is described using synthetic pin standards pressed from solution doped copper and zinc matrices. A special pressing die was developed for this purpose and optimal results were obtained with the highest possible pressures, i.e., 95 kN·cm- 2. This calibration approach permits the determination of trace element mass fractions down to µg·kg- 1 with small uncertainties and additionally provides traceability of the GD-MS results in the most direct manner to the SI (International System of Units). Results were validated by concurrent measurements of a number of compact copper and zinc certified reference materials. The impact of the sample pin cross-section (circular or square) was investigated with the use of a new pin-sample holder system for the Element GD. The pin-sample holder was designed by the manufacturer for pin-samples having circular cross-section; however, samples with square pin cross-section were also shown to provide acceptable results. Relative Sensitivity Factors for some 50 analytes in copper (VG 9000, Element GD) and zinc matrices (VG 9000) are presented. The field of applicability of GD-MS may be considerably extended via analysis of pin geometry samples based on their ease of preparation, especially with respect to the accuracy and traceability of the results and the enhanced number of analytes which can be reliably calibrated using such samples. KW - Glow discharge KW - Pin sample KW - Calibration PY - 2011 U6 - https://doi.org/10.1016/j.sab.2011.12.001 SN - 0584-8547 SN - 0038-6987 VL - 66 IS - 11-12 SP - 847 EP - 854 PB - Elsevier CY - Amsterdam AN - OPUS4-25346 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -