TY - JOUR A1 - Matschat, Ralf A1 - Heinrich, Hans-Joachim A1 - Czerwensky, Michael A1 - Kuxenko, Sandra A1 - Kipphardt, Heinrich T1 - Multielement trace determination in high purity advanced ceramics and high purity metals T2 - International Symposium on Ultrapure Materials (ISUPM) CY - Hyderabad, India DA - 2004-11-22 KW - Advanced ceramics KW - Pure metals KW - SS ET AAS KW - HR ICP-MS PY - 2005 SN - 0250-4707 SN - 0973-7669 VL - 28 IS - 4 SP - 361 EP - 366 PB - Indian Academy of Sciences CY - Bangalore AN - OPUS4-10889 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinrich, Hans-Joachim A1 - Kipphardt, Heinrich T1 - Application of methane as a gaseous modifier for the determination of silicon using electrothermal atomic absorption spectrometry N2 - For determination of silicon in aqueous solutions by electrothermal atomic absorption spectrometry methane/argon mixtures as a gaseous modifier were applied during the pyrolysis step to improve the analytical performance. The beneficial effects observed on thermal stabilization, signal enhancement and shape of absorbance signals were attributed to the thermal decomposition products of methane, which were hydrogen and carbon black (soot). Using a 5% CH4 mixture with argon, the optimized pyrolysis and atomization temperatures were 1350 °C and 2450 °C, respectively. A flushing step following the pyrolysis was mandatory to avoid background absorption and accelerated deposition of pyrolytic graphite. Characteristic masses of 50 and 30 pg were obtained for standard transversely heated graphite atomizer (THGA) tubes and end-capped THGA tubes, respectively, which were lower than with other previously applied modifiers. A limit of detection of 0.2 µg L- 1 (3 s, n = 10) has been obtained. In addition, this gaseous modifier did not contribute to contamination which often was significant when a liquid modifier solution was co-injected. The proposed method has been applied to the determination of silicon in ultrapure water, nitric and hydrochloric acids. KW - Electrothermal atomic absorption KW - Spectrometry KW - Silicon determination KW - Methane KW - Modifier KW - Ultrapure reagents PY - 2012 U6 - https://doi.org/10.1016/j.sab.2012.04.001 SN - 0584-8547 SN - 0038-6987 VL - 70 SP - 68 EP - 73 PB - Elsevier CY - Amsterdam AN - OPUS4-26050 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - 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 - Matschat, Ralf A1 - Czerwensky, Michael A1 - Kuxenko, Sandra A1 - Heinrich, Hans-Joachim T1 - Certification of high purity metals as primary reference materials - a challenge for multielement trace analysis N2 - The Bundesanstalt für Materialforschung und -prüfung (Federal Institute for Materials Research and Testing) (BAM) is establishing a system of primary reference materials to meet the demands for metrological traceability and to act as national standards in the field of elemental analysis. For all elements of the periodic table - except those that are gases or radioactive - two different kinds of reference materials are being certified. One is for analyte calibration (Type A) and one for problems concerning matrix matching (Type B). These substances are of very high purity and of defined stoichiometry. As far as possible, pure elements and metals rather than pure compounds are used. The certification of both types of material requires most elements of the periodic table to be certified at very low levels using trace element analysis methods. The application of these methods is described and examples of the certification of copper and iron are given. KW - Elementspurenanalytik KW - Primäre Referenzmaterialien PY - 2002 U6 - https://doi.org/10.1002/1521-396X(200201)189:1%3C107::AID-PSSA107%3E3.0.CO;2-1 SN - 1862-6300 SN - 0031-8965 N1 - Geburtsname von Kuxenko, Sandra: Pattberg, S. - Birth name of Kuxenko, Sandra: Pattberg, S. VL - 189 IS - 1 SP - 107 EP - 122 PB - Wiley-VCH CY - Berlin AN - OPUS4-837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Matschat, Ralf A1 - Czerwensky, Michael A1 - Pattberg, S. A1 - Heinrich, Hans-Joachim A1 - Tutschku, S. T1 - High Purity Metals as Primary Calibration Materials for Elemental Analysis - Their Importance and Their Certification N2 - The Bundesanstalt fuer Materialforschung und -pruefung, BAM (Federal Institute for Materials Research and Testing) continues to establish a system of primary reference materials to meet the demands of metrological traceability. The materials act as national standards in the field of elemental analysis. For all elements of the periodic table -excepting those that are gases or radioactive- two different kinds of reference materials are being certified. The substances are of very high purity and of defined stoichiometry. Pure elements and metals are used as far as possible. They are certified by determining the trace contents of most elements of the periodic table at very low levels using different trace element analysis methods. Recent application of these methods is described and examples of the certification of some pure metals (copper, iron and lead) are given. (author abst.) T2 - 8th International Conference on Ultra-High Purity Base Metals (UHPM-2001) CY - Berlin, Germany DA - 2001-06-25 KW - Trace elemental analysis KW - Atomic spectrometry KW - High purity metals KW - Certification KW - Primary calibration materials KW - Reference materials KW - National standards PY - 2002 UR - https://www.researchgate.net/publication/235927297_High_purity_metals_as_primary_calibration_materials_for_elemental_analysis_-_Their_importance_and_their_certification SN - 1345-9678 SN - 1347-5320 VL - 43 IS - 2 SP - 90 EP - 97 PB - Japan Institute of Metals CY - Sendai AN - OPUS4-1600 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinrich, Hans-Joachim A1 - Matschat, Ralf T1 - Investigations on Freon-assisted atomization of refractory analytes (Cr, Mo, Ti, V) in multielement electrothermal atomic absorption spectrometry N2 - Premixed 1% Freon in argon inner gas of various composition (CCl2F2, CHClF2, CHF3) was applied to graphite furnace atomizer to minimize unfavorable effects of carbide formation, such as signal tailing and memory effects in the simultaneous determination of Cr, Mo, Ti and V refractory analytes by electrothermal atomic absorption spectrometry using a multielement atomic absorption spectrometer. The effect of these gaseous additives was investigated when applied separately in atomization, pyrolysis and clean-out steps. The halogenation effects were analytically useful only under the precondition of using Ar–H2 outer gas to the furnace to all heating steps, and also using this gas in the pre-atomization (drying, pyrolysis) steps. Optimum analytical performance was obtained when mixtures of 1% Freon in argon were applied just before and during the atomization step at a flow rate of 50 mL min- 1 and 2% hydrogen was used as purge gas. Using optimum conditions, signal tailings and carry-over contamination were reduced effectively and good precision (relative standard deviation below 1%) could be attained. Applying 1% CHClF2 and an atomization temperature of 2550 °C, the characteristic masses obtained for simple aqueous solutions were 8.8 pg for Cr, 17 pg for Mo, 160 pg for Ti, and 74 pg for V. The limits of detection were 0.05, 0.2, 2.3 and 0.5 µg L- 1 for Cr, Mo, Ti and V, respectively. The developed method was applied to the analysis of digests of advanced ceramics. The accuracy of the procedure was confirmed by analyzing the certified reference material ERM-ED 102 (Boron Carbide Powder) and a silicon nitride powder distributed in the inter-laboratory comparison CCQM-P74. KW - Electrothermal atomic absorption spectrometry KW - Refractory analytes KW - Carry-over contamination KW - Halogenation KW - Freon PY - 2007 U6 - https://doi.org/10.1016/j.sab.2007.06.006 SN - 0584-8547 SN - 0038-6987 VL - 62 IS - 8 SP - 807 EP - 816 PB - Elsevier CY - Amsterdam AN - OPUS4-15833 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abad Andrade, Carlos Enrique A1 - Florek, S. A1 - Becker-Ross, H. A1 - Huang, M.-D. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Lippitz, Andreas A1 - Hodoroaba, Vasile-Dan A1 - Schmid, Thomas A1 - Heinrich, Hans-Joachim A1 - Recknagel, Sebastian A1 - Jakubowski, Norbert A1 - Panne, Ulrich T1 - Zirconium permanent modifiers for graphite furnaces used in absorption spectrometry: understanding their structure and mechanism of action N2 - The mechanism of action of zirconium permanent modifiers on graphite surfaces was investigated in order to understand its influence on the analytical signal in atomic and molecular absorption spectrometry (AAS/MAS). For this, the molecule formation of CaF was studied, which is used for the indirect analytical determination of fluorine in high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). The kinetics of this reaction was established by monitoring its molecular spectrum at different atomisation temperatures. An Arrhenius plot showed a pseudo-first order reaction with respect to fluorine (n = 1). An intermediate state was isolated, and its structure was elucidated by spectroscopic methods: scanning electron microscopy with energy dispersive X-ray spectroscopy (SEMEDX), X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XANES and EXAFS), and Raman microspectroscopy. We propose here a mechanism, where ZrO2 acts as a heterogeneous catalyst: after a pyrolytic step, an intermediate state of ZrO(OCaF) is activated, and at higher temperatures, CaF(g) is released from the zirconium-coated graphite surface. No evidence of the formation of zirconium carbide was found. Consequently, as the CaF formation is catalysed by a heterogeneous catalyst, surface modifications with ZrO2 nanoparticles and ZrO xerogels were investigated in order to increase the surface area. Their influence was evaluated in the molecule formation of CaF, CaCl, CaBr, and CaI. Graphite furnace modification with zirconium oxide nanoparticles proves to be the best choice for fluorine analysis with a signal enhancement of more than eleven times with respect a non-coated graphite furnace. However, the influence of zirconium modifications in the analytical signals of Cl, and I is lower than the F signals or even negative in case of the Br. Understanding zirconium modifiers as heterogeneous catalysts offers a new perspective to AAS and MAS, and reveals the potential of surface analytical methods for development of improved permanent modifiers and graphite furnace coatings. KW - Zirconium KW - HR-CS-MAS KW - Graphite furnace KW - Nanoparticles KW - Xerogel KW - Calcium monofluoride KW - Absorption spectrometry PY - 2018 UR - https://pubs.rsc.org/en/content/articlelanding/2018/ja/c8ja00190a U6 - https://doi.org/10.1039/C8JA00190A SN - 0267-9477 VL - 33 IS - 12 SP - 2034 EP - 2042 PB - Royal Society of Chemistry AN - OPUS4-46775 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abad Andrade, Carlos Enrique A1 - Florek, S. A1 - Becker-Ross, H. A1 - Huang, M.-D. A1 - Heinrich, Hans-Joachim A1 - Recknagel, Sebastian A1 - Vogl, Jochen A1 - Jakubowski, Norbert A1 - Panne, Ulrich T1 - Determination of boron isotope ratios by high-resolution continuum source molecular absorption spectrometry using graphite furnace vaporizers N2 - Boron isotope amount ratios n(10B)/n(11B) have been determined by monitoring the absorption spectrum of boron monohydride (BH) in a graphite furnace using high-resolution continuum source molecular absorption spectrometry (HR-CS-MAS). Bands (0→0) and (1→1) for the electronic transition X1Σ+ → A1Π were evaluated around wavelengths 433.1 nm and 437.1 nm respectively. Clean and free of memory effect molecular spectra of BH were recorded. In order to eliminate the memory effect of boron, a combination of 2% (v/v) hydrogen gas in argon and 1% trifluoromethane in argon, an acid solution of calcium chloride and mannitol as chemical modifiers was used. Partial least square regression (PLS) for analysis of samples and reference materials were applied. For this, a spectral library with different isotopes ratios for PLS regression was built. Results obtained around the 433.1 nm and 437.1 nm spectral regions are metrologically compatible with those reported by mass spectrometric methods. Moreover, for the evaluated region of 437 nm, an accuracy of 0.15‰ is obtained as the average deviation from the isotope reference materials. Expanded uncertainties with a coverage factor of k = 2 range between 0.15 and 0.44‰. This accuracy and precision are compatible with those obtained by mass spectrometry for boron isotope ratio measurements. KW - Boron isotopes KW - Isotope ratios KW - Boron monohydride KW - Molecular absorption KW - High-resolution continuum source absorption spectrometry KW - Graphite furnace KW - Memory effect KW - HR-CS-MAS PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S0584854717302537 U6 - https://doi.org/10.1016/j.sab.2017.08.012 SN - 0584-8547 VL - 136 SP - 116 EP - 122 PB - Elsevier CY - Amsterdam, The Netherlands AN - OPUS4-42071 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -