TY - JOUR A1 - Noble, J.E. A1 - Wang, L. A1 - Cerasoli, E. A1 - Knight, A.E. A1 - Porter, R.A. A1 - Gray, E. A1 - Howe, C. A1 - Hannes, E. A1 - Corbisier, P. A1 - Wang, J. A1 - Wu, L. A1 - Altieri, I. A1 - Patriarca, M. A1 - Hoffmann, Angelika A1 - Resch-Genger, Ute A1 - Ebert, B. A1 - Voigt, Jan A1 - Shigeri, Y. A1 - Vonsky, M.S. A1 - Konopelko, L.A. A1 - Gaigalas, A.K. A1 - Bailey, M. J. A. T1 - An international comparability study to determine the sources of uncertainty associated with a non-competitive sandwich fluorescent ELISA KW - ELISA KW - Fluorescence KW - Interferon KW - Uncertainty KW - Round Robin KW - Immunoassay KW - Quality assurance KW - Fluorescein PY - 2008 SN - 1434-6621 SN - 1437-8523 VL - 46 IS - 7 SP - 1033 EP - 1045 PB - De Gruyter CY - Berlin AN - OPUS4-18283 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Frenz, Holger A1 - Gruhn, B. A1 - Dietrich, C. A1 - Lehmann, J. A1 - Krämer, E. A1 - Glaubitz, Steffen A1 - Wimmer, J. A1 - Rehmer, Birgit A1 - Kühn, Hans-Dieter A1 - Breitkreutz, Konrad A1 - Portella, Pedro Dolabella A1 - Hoffmann, E. A1 - Ziebs, Josef T1 - Sphäroguß als Werkstoff für Behälter zur Beförderung, Zwischen- und Endlagerung radioaktiver Stoffe; Untersuchung zu alternativen Eignungsnachweisen - Fachband 3: Werkstoffuntersuchungen, 1989 - 1992 N2 - Gußeisen mit Kugelgraphit und ferritischer bzw. ferritisch-perlitischer Matrix gehören zu einer Werkstoffgruppe, die ausreichende Festigkeiten mit hohen Duktilitäten verbindet. Mit der vorliegenden Arbeit wurden die Kenntnisse über die Zusammenhänge zwischen der chemischen Zusammensetzung, der Gefügeausbildung und den mechanischen Eigenschaften erweitert. Dabei wurden sowohl unterschiedliche Gießverfahren (Sand- und Kokillenguß) in der Herstellung, als auch die Auswirkungen von Umwandlungsprozessen im Gefüge infolge von Wärmebehandlungen diskutiert. Die statistische Auswertung von Einzelergebnissen aus der qualitätssichernden Begutachtung von Lager- und Transportbehältern für radioaktive Stoffe wurden durch mechanische und bruchmechanische Untersuchungen an 24 Werkstoffsorten aus Gußeisen mit Kugelgraphit ergänzt. KW - Eignungsnachweis KW - Endlagerung KW - Lagerbehälter KW - Radioaktiver Stoff KW - Sphäroguß (GGG-40) KW - Transportbehälter KW - Zwischenlagerung PY - 1992 N1 - Das Projekt wurde gefördert vom Bundesminister für Forschung und Technologie (BMFT); Förderkennzeichen: KWA 79052. SP - 1 EP - 178 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-59950 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chan, George C.-Y. A1 - Hieftje, Gary M. A1 - Omenetto, Nicoló A1 - Axner, Ove A1 - Bengtson, Arne A1 - Bings, Nicolas H. A1 - Blades, Michael W. A1 - Bogaerts, Annemie A1 - Bolshov, Mikhail A. A1 - Broekaert, José A.C. A1 - Chan, WingTat A1 - Costa-Fernández, José M. A1 - Crouch, Stanley R. A1 - De Giacomo, Alessandro A1 - D’Ulivo, Alessandro A1 - Engelhard, Carsten A1 - Falk, Heinz A1 - Farnsworth, Paul B. A1 - Florek, Stefan A1 - Gamez, Gerardo A1 - Gornushkin, Igor B. A1 - Günther, Detlef A1 - Hahn, David W. A1 - Hang, Wei A1 - Hoffmann, Volker A1 - Jakubowski, Norbert A1 - Karanassios, Vassili A1 - Koppenaal, David W. A1 - Kenneth Marcus, R. A1 - Noll, Reinhard A1 - Olesik, John W. A1 - Palleschi, Vincenzo A1 - Panne, Ulrich A1 - Pisonero, Jorge A1 - Ray, Steven J. A1 - Resano, Martín A1 - Russo, Richard E. A1 - Scheeline, Alexander A1 - Smith, Benjamin W. A1 - Sturgeon, Ralph E. A1 - Todolí, José-Luis A1 - Tognoni, Elisabetta A1 - Vanhaecke, Frank A1 - Webb, Michael R. A1 - Winefordner, James D. A1 - Yang, Lu A1 - Yu, Jin A1 - Zhang, Zhanxia T1 - Landmark Publications in Analytical Atomic Spectrometry: Fundamentals and Instrumentation Development N2 - The almost-two-centuries history of spectrochemical analysis has generated a body of literature so vast that it has become nearly intractable for experts, much less for those wishing to enter the field. Authoritative, focused reviews help to address this problem but become so granular that the overall directions of the field are lost. This broader perspective can be provided partially by general overviews but then the thinking, experimental details, theoretical underpinnings and instrumental innovations of the original work must be sacrificed. In the present compilation, this dilemma is overcome by assembling the most impactful publications in the area of analytical atomic spectrometry. Each entry was proposed by at least one current expert in the field and supported by a narrative that justifies its inclusion. The entries were then assembled into a coherent sequence and returned to contributors for a round-robin review. KW - Analytical atomic spectrometry KW - Spectroscopy KW - Instrumental analysis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621588 DO - https://doi.org/10.1177/00037028241263567 SN - 1943-3530 VL - 78 SP - 1 EP - 456 PB - Sage CY - London AN - OPUS4-62158 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schrezenmeier, E. A1 - Hoffmann, F. A1 - Jaeger, C. A1 - Schrezenmeier, J. A1 - Lisec, Jan A1 - Glander, P. A1 - Algharably, E. A1 - Kreutz, R. A1 - Budde, K. A1 - Duerr, M. A1 - Halleck, F. T1 - Pharmacokinetics of Daclatasvir, Sofosbuvir and GS-331007 in a Prospective Cohort of HCV positive Kidney Transplant Recipients N2 - Limited data exist on the pharmacokinetic profile of novel direct acting antivirals in kidney transplant recipients. Daclatasvir is primarily eliminated via the biliary route and sofosbuvir via the renal route; here we report the pharmacokinetic profile of combined treatment with these compounds in a prospective study of hepatitis C virus positive kidney transplant recipients (EudraCT: 2014-004551-32). In this study plasma samples of 16 HCV positive kidney transplant recipients receiving daclatasvir and sofosbuvir were collected at 4 time points at day 1, 7, 14, 21, 56, and 84 after start of treatment. Inclusion criteria were stable graft function and an estimated GFR (eGFR) > 30mL/min/1.73m. Daclatasvir, sofosbuvir and GS-331007 (inactive metabolite of sofosbuvir) plasma concentrations were determined using ultra-performance liquid chromatography quadrupole time of flight mass spectrometry. All patients showed a rapid virological response with HCV RNA below the detection limit 21 days after the start of therapy (medium time to viral clearance). No difference of the areas under the concentration-time curve (AUC) of daclatsavir, sofosbuvir and GS-331007 was observed between patients with an eGFR below or ≥ 60mL/min. For GS-331007, no relevant changes of trough levels were observed over time. Mean GS-331007 trough levels were 339.5±174.9 ng/mL in patients with an eGFR ≥ 60mL/min and 404.3±226 ng/mL in patients with an eGFR < 60mL/min at day 7 (p=0.52). At day 84, GS-331007 trough levels were 357.8±200.8 ng/mL and 404.2±70.2 ng/mL in patients with an eGFR ≥ 60 mL/min and in patients with an eGFR < 60 mL/min, respectively (p=0.51). The accumulation ratios of renally eliminated GS-331007 for AUC and Cmax did not significantly differ between the two eGFR groups at day 7. An impaired eGFR (30-60 mL/min) does not lead to a dose accumulation of daclatasvir, sofosbuvir and GS-331007. This study provides the rationale for future studies investigating the pharmacokinetic profile of sofosbuvir based HCV treatment in kidney transplant recipients with an eGFR < 30 mL/min. KW - Mass-Spectrometry PY - 2018 DO - https://doi.org/10.1097/FTD.0000000000000567 SN - 0163-4356 VL - 41 IS - 1 SP - 53 EP - 58 PB - Wolters Kluwer AN - OPUS4-46647 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kazlagić, Anera A1 - Rosner, M. A1 - Cipriani, A. A1 - Frick, D. A. A1 - Glodny, J. A1 - Hoffmann, E. J. A1 - Hora, J. M. A1 - Irrgeher, J. A1 - Lugli, F. A1 - Magna, T. A1 - Meisel, T. C. A1 - Meixner, A. A1 - Possolo, A. A1 - Pramann, A. A1 - Pribil, M. J. A1 - Prohaska, T. A1 - Retzmann, A. A1 - Rienitz, O. A1 - Rutherford, D. A1 - Paula-Santos, G. M. A1 - Tatzel, M. A1 - Widhalm, S. A1 - Willbold, M. A1 - Zuliani, T. A1 - Vogl, Jochen T1 - Data of the characterisation of conventional 87Sr/86Sr isotope ratios in cement, limestone and slate reference materials based on an interlaboratory comparison study N2 - This dataset represents the electronic supplementary material (ESM) of the publication entitled "Characterisation of conventional 87Sr/86Sr isotope ratios in cement, limestone and slate reference materials based on an interlaboratory comparison study", which is published in Geostandards and Geoanalytical Research under the DOI: 10.1111/GGR.12517. It consists of four files. 'ESM_Data.xlsx' contains all reported data of the participants, a description of the applied analytical procedures, basic calculations, the consensus values, and part of the uncertainty assessment. 'ESM_Figure-S1' displays a schematic on how measurements, sequences and replicates are treated for the uncertainty calculation carried out by PTB. 'ESM_Technical-protocol.pdf' is the technical protocol of the interlaboratory comparison, which has been provided to all participants together with the samples and which contains bedside others the definition of the measurand and guidelines for data assessment and calculations. 'ESM_Reporting-template.xlsx' is the Excel template which has been submitted to all participants for reporting their results within the interlaboratory comparison. Excel files with names of the the structure 'GeoReM_Material_Sr8786_Date.xlsx' represent the Rcon(87Sr/86Sr) data for a specific reference material downloaded from GeoReM at the specified date, e.g. 'GeoReM_IAPSO_Sr8786_20221115.xlsx' contains all Rcon(87Sr/86Sr) data for the IAPSO seawater standard listed in GeoReM until 15 November 2022. KW - Reference data KW - Strontium isotope ratio KW - Interlaboratory comparison KW - Reference material KW - Cement KW - Geological material KW - Value assignment KW - Measurement uncertainty KW - Conventional method PY - 2023 UR - https://doi.org/10.5281/zenodo.7804445 DO - https://doi.org/10.5281/zenodo.7804444 PB - Zenodo CY - Geneva AN - OPUS4-57809 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kazlagić, Anera A1 - Rosner, M. A1 - Cipriani, A. A1 - Frick, D. A. A1 - Glodny, J. A1 - Hoffmann, E. J. A1 - Hora, J. M. A1 - Irrgeher, J. A1 - Lugli, F. A1 - Magna, T. A1 - Meisel, T. C. A1 - Meixner, A. A1 - Possolo, A. A1 - Pramann, A. A1 - Pribil, M. J. A1 - Prohaska, T. A1 - Retzmann, Anika A1 - Rienitz, O. A1 - Rutherford, D. A1 - Paula-Santos, G. M. A1 - Tatzel, M. A1 - Widhalm, S. A1 - Willbold, M. A1 - Zuliani, T. A1 - Vogl, Jochen T1 - Characterisation of conventional 87Sr/86Sr isotope ratios in cement, limestone and slate reference materials based on an interlaboratory comparison study N2 - An interlaboratory comparison (ILC)was organised to characterise 87Sr/86Sr isotope ratios in geological and industrial reference materials by applying the so-called conventional method for determining 87Sr/86Sr isotope ratios. Four cements (VDZ 100a,VDZ 200a, VDZ 300a, IAG OPC-1), one limestone (IAG CGL ML-3) and one slate (IAG OU-6) reference materials were selected, covering a wide range of naturally occurring Sr isotopic signatures. Thirteen laboratories received aliquots of these six reference materials together with a detailed technical protocol. The consensus values for the six reference materials and their associated measurement uncertainties were obtained by applying a Gaussian, linear mixed effects model fitted to all the measurement results. By combining the consensus values and their uncertainties with an uncertainty contribution for potential heterogeneity, reference values ranging from 0.708134 mol mol-1 to 0.729778 mol mol-1 were obtained with relative expanded uncertainties of ≤ 0.007 %. This study represents an ILC on conventional 87Sr/86Sr isotope ratios, within which metrological principles were considered and the compatibility of measurement results obtained by MC-ICP-MS and by MC-TIMS is demonstrated. The materials characterised in this study can be used as reference materials for validation and quality control purposes and to estimate measurement uncertainties in conventional 87Sr/86Sr isotope ratio measurement. KW - Sr isotope analysis KW - Isotope ratios KW - Cement KW - Geological material KW - MC-TIMS KW - MC-ICP-MS KW - Interlaboratory comparison KW - Measurement uncertainty KW - Cconventional method PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579836 DO - https://doi.org/10.1111/ggr.12517 SN - 1639-4488 VL - 47 IS - 4 SP - 821 EP - 840 PB - Wiley online library AN - OPUS4-57983 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Grotheer, E. A1 - Vogel, Christian A1 - Kolomiets, O. A1 - Hoffmann, U. A1 - Unger, M. A1 - Siesler, H.W. ED - Salzer, R. ED - Siesler, H.W. T1 - FT-IR and NIR spectroscopic imaging: principles, practical aspects, and applications in material and pharmaceutical science PY - 2014 SN - 978-3-527-33652-4 SN - 978-3-527-67816-7 SN - 978-3-527-67815-0 SN - 978-3-527-67814-3 SN - 978-3-527-67813-6 SP - Chapter 8, 341 EP - 396 PB - Wiley-VCH Verlag GmbH & Co. KGaA ET - 2nd Edition AN - OPUS4-31432 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Göbel, E. O. A1 - Hasche, K. A1 - Ulm, G. A1 - Krumrey, M. A1 - Ade, G. A1 - Stümpel, J. A1 - Herrmann, K. A1 - Koenders, L. A1 - Thomsen-Schmidt, P. A1 - Pohlenz, F. A1 - Xu, M. A1 - Dai, G. A1 - Hoffmann, K.-P. A1 - Busch, I. A1 - Frank, W. A1 - Procop, M. A1 - Beck, Uwe T1 - Kalibrierte Schichtdicken-Maßverkörperungen für Nanometerschichten, Teilvorhaben - Kalibrierung von Schichtdicken-Maßverkörperungen im Nanometerbereich - Abschlussbericht des BMBF Verbundvorhabens 13N7704 - 13N77041 KW - Schichtdicke KW - Nanometerbereich PY - 2003 UR - http://edok01.tib.uni-hannover.de/edoks/e01fb02/373214030.pdf SP - 1 EP - 131 PB - Physikalisch-Technische Bundesanstalt CY - Dresden AN - OPUS4-25428 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hörmann, Anja F. A1 - Simon, Miriam A1 - Brückner, Christoph A1 - Rogers, Sarah E. A1 - Porcar, Lionel A1 - Hoffmann, Ingo A1 - Gradzielski, Michael T1 - Line tension controls the spontaneous formation of vesicles N2 - Mixtures of the zwitterionic surfactant TDMAO and the anionic surfactant LiPFOS spontaneously self-assemble into well defined vesicles. The size of these vesicles is determined by the ratio of bending rigidity and line tension. By partially charging TDMAO, and thereby moving more to a catanionic system, the size of these vesicles can be controlled. Using stopped flow small angle neutron scattering we monitor the kinetics of vesicle formation and obtain their final size. Neutron spin echo spectroscopy allows for an independent measurement of the vesicle’s bending rigidity. Combining this bending rigidity with the radius of newly formed vesicles, which is determined by the ratio of bending rigidity and line tension, we can determine the line tension. We find that it is the line tension that controls the trend in size of the vesicles. In summary, this means that here one has a surfactant mixture that delivers well-defined vesicles, whose size is controlled by the electrostatic interactions of the head groups. KW - Self-assembly KW - Small unilamellar vesicles KW - Small-angle neutron scattering KW - Line tension KW - Neutron spin-echo spectroscopy KW - Stopped-flow KW - Bending rigidity KW - Surfactant mixture PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-646964 DO - https://doi.org/10.1039/D5SM00600G SN - 1744-683X VL - 21 IS - 43 SP - 8360 EP - 8367 PB - Royal Society of Chemistry (RSC) AN - OPUS4-64696 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Angeli, J. A1 - Bengtson, A. A1 - Bogaerts, A. A1 - Hoffmann, V. A1 - Hodoroaba, Vasile-Dan A1 - Steers, E. T1 - Glow discharge optical emission spectrometry: moving towards reliable tion film analysis - a short review N2 - Glow discharge optical emission spectroscopy (GD-OES) is briefly reviewed, with particular reference to topics relevant to the application field of near surface and thin film analysis. The special needs and requirements for thin film analysis, in contrast to coating and bulk analysis, are pointed out. A task list is developed which shows the requirements of further developments to the technique and the fundamentals. The state-of-the-art is presented in measurement technique, GD source control and design, the effect of traces of molecular gases, correction and quantification procedures, contributions of modelling and, finally, reference materials for thin film analysis. PY - 2003 DO - https://doi.org/10.1039/b301293j SN - 0267-9477 SN - 1364-5544 VL - 18 IS - 6 SP - 670 EP - 679 PB - Royal Society of Chemistry CY - London AN - OPUS4-2533 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Hoffmann, V. A1 - Steers, E. B. M. T1 - Exploitation of the hydrogen effect on an analytical glow discharge T2 - Final General Meeting of the EU-GDS Network CY - Wiener Neustadt, Austria DA - 2002-03-02 PY - 2002 SP - 1(?) EP - 6(?) AN - OPUS4-1467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Hoffmann, V. A1 - Steers, E. A1 - Wetzig, K. T1 - Investigations of the emission processes in argon glow discharges containing hydrogen T2 - Winter Conference on Plasma Spectrochemistry 2000 CY - Fort Lauderdale, FL, USA DA - 2000-01-10 PY - 2000 SN - 0161-6951 VL - 25 SP - 302 EP - 303 PB - ICP Information Newsletter, Inc. CY - Amherst, Mass. AN - OPUS4-6884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Klemm, D. A1 - Reinholz, Uwe A1 - Strub, E. A1 - Röhrich, J. A1 - Bohne, W. A1 - Hoffmann, V. A1 - Wetzig, K. T1 - Potential candidates of certified reference material for determination of hydrogen concentration with glow discharge optical emission spectrometry (GD-OES) - a feasibility study N2 - Three different coatings/layers have been found in a feasibility study as potential candidates for certified reference materials for the determination of hydrogen concentration by GD-OES: (i) electroplated zinc, (ii) carbon-rich coatings and (iii) amorphous silicon layers. KW - CRM KW - Hydrogen KW - GDS PY - 2008 DO - https://doi.org/10.1039/b717924c SN - 0267-9477 SN - 1364-5544 VL - 23 SP - 460 EP - 462 PB - Royal Society of Chemistry CY - London AN - OPUS4-17335 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Geißler, Daniel A1 - Wegmann, Marc A1 - Jochum, T. A1 - Somma, V. A1 - Sowa, M. A1 - Scholz, J. A1 - Fröhlich, E. A1 - Hoffmann, Katrin A1 - Niehaus, J. A1 - Roggenbuck, D. A1 - Resch-Genger, Ute T1 - An automatable platform for genotoxicity testing of nanomaterials based on the fluorometric γ-H2AX assay reveals no genotoxicity of properly surface-shielded cadmium-based quantum dots N2 - The large number of nanomaterial-based applications emerging in the materials and life sciences and the foreseeable increasing use of these materials require methods that evaluate and characterize the toxic potential of these nanomaterials to keep safety risks to people and environment as low as possible. As nanomaterial toxicity is influenced by a variety of parameters like size, shape, chemical composition, and surface chemistry, high throughput screening (HTS) platforms are recommended for assessing cytotoxicity. Such platforms are not yet available for genotoxicity testing. Here, we present first results obtained for application-relevant nanomaterials using an automatable genotoxicity platform that relies on the quantification of the phosphorylated histone H2AX (γ-H2AX) for detecting DNA double strand breaks (DSBs) and the automated microscope system AKLIDES® for measuring integral fluorescence intensities at different excitation wavelengths. This platform is used to test the genotoxic potential of 30 nm-sized citrate-stabilized gold nanoparticles (Au-NPs) as well as micellar encapsulated iron oxide nanoparticles (FeOx-NPs) and different cadmium (Cd)-based semiconductor quantum dots (QDs), thereby also searching for positive and negative controls as reference materials. In addition, the influence of the QD shell composition on the genotoxic potential of these Cd-based QDs was studied, using CdSe cores as well as CdSe/CdS core/shell and CdSe/CdS/ZnS core/shell/shell QDs. Our results clearly revealed the genotoxicity of the Au-NPs and its absence in the FeOx-NPs. The genotoxicity of the Cd-QDs correlates with the shielding of their Cd-containing core, with the core/shell/shell architecture preventing genotoxicity risks. The fact that none of these nanomaterials showed cytotoxicity at the chosen particle concentrations in a conventional cell viability assay underlines the importance of genotoxicity studies to assess the hazardous potential of nanomaterials. KW - Nanomaterial KW - Genotoxicity testing KW - γ-H2AX assay KW - Quantum dot PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-486318 DO - https://doi.org/10.1039/C9NR01021A SN - 2040-3372 SN - 2040-3364 VL - 11 IS - 28 SP - 13458 EP - 13468 PB - The Royal Society of Chemistry AN - OPUS4-48631 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Hoffmann, V. A1 - Wetzig, K. A1 - Steers, E. T1 - ThP33 Investigations of the emission processes in argon glow discharges containing hydrogen T2 - Winter Conference on Plasma Spectrochemistry 2000 CY - Fort Lauderdale, FL, USA DA - 2000-01-10 PY - 2000 SN - 0161-6951 VL - 25 SP - 1 EP - 2 PB - ICP Information Newsletter, Inc. CY - Amherst, Mass. AN - OPUS4-846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Hoffmann, V. A1 - Steers, E. B. M. A1 - Wetzig, K. T1 - Exploitation of the effect of hydrogen on an analytical glow discharge T2 - Winter Conference on Plasma Spectrochemistry 2002 CY - Scottsdale, AZ, USA DA - 2002-01-06 PY - 2002 SN - 0161-6951 SP - 261 EP - 262 PB - ICP Information Newsletter, Inc. CY - Amherst, Mass. AN - OPUS4-1589 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bruna, F. G. A1 - Prokop, M. A1 - Bystron, T. A1 - Loukrakpam, R. A1 - Melke, J. A1 - Lobo, C. M. S. A1 - Fink, M. A1 - Zhu, M. A1 - Voloshina, E. A1 - Kutter, M. A1 - Hoffmann, H. A1 - Yusenko, Kirill A1 - de Oliveira Guilherme Buzanich, Ana A1 - Röder, B. A1 - Bouzek, K. A1 - Paulus, B. A1 - Roth, C. T1 - Following adsorbed intermediates on a platinum gas diffusion electrode in H3PO3‑containing electrolytes using in situ X‑ray absorption spectroscopy N2 - One of the challenges of high-temperature polymer electrolyte membrane fuel cells is the poisoning of the Pt catalyst with H3PO4. H3PO4 is imbibed into the routinely used polybenzimidazole-based membranes, which facilitate proton conductivity in the temperature range of 120−200 °C. However, when leached out of the membrane by water produced during operation, H3PO4 adsorbs on the Pt catalyst surface, blocking the active sites and hindering the oxygen reduction reaction (ORR). The reduction of H3PO4 to H3PO3, which occurs at the anode due to a combination of a low potential and the presence of gaseous H2, has been investigated as an additional important contributing factor to the observed poisoning effect. H3PO3 has an affinity toward adsorption on Pt surfaces even greater than that of H2PO4 −. In this work, we investigated the poisoning effect of both H3PO3 and H3PO4 using a half-cell setup with a gas diffusion electrode under ambient conditions. By means of in situ X-ray absorption spectroscopy, it was possible to follow the signature of different species adsorbed on the Pt nanoparticle catalyst (H, O, H2PO4 −, and H3PO3) at different potentials under ORR conditions in various electrolytes (HClO4, H3PO4, and H3PO3). It was found that H3PO3 adsorbs in a pyramidal configuration P(OH)3 through a Pt−P bond. The competition between H3PO4 and H3PO3 adsorption was studied, which should allow for a better understanding of the catalyst poisoning mechanism and thus assist in the development of strategies to mitigate this phenomenon in the future by minimizing H3PO3 generation by, for example, improved catalyst design or adapted operation conditions or changes in the electrolyte composition. KW - H3PO4 life cycle KW - XAS KW - In situ coupling KW - High-temperature fuel cells KW - Δμ XANES KW - H3PO3 PY - 2022 DO - https://doi.org/10.1021/acscatal.2c02630 SN - 2155-5435 VL - 12 IS - 18 SP - 11472 EP - 11484 PB - ACS CY - Washington, DC AN - OPUS4-55815 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wolf, S. E. A1 - Müller, L. A1 - Barrea, R. A1 - Kampf, C.J. A1 - Leiterer, Jork A1 - Panne, Ulrich A1 - Hoffmann, T. A1 - Emmerling, Franziska A1 - Tremel, W. T1 - Carbonate-coordinated metal complexes precede the formation of liquid amorphous mineral emulsions of divalent metal carbonates N2 - During the mineralisation of metal carbonates MCO3 (M = Ca, Sr, Ba, Mn, Cd, Pb) liquid-like amorphous intermediates emerge. These intermediates that form via a liquid/liquid phase separation behave like a classical emulsion and are stabilized electrostatically. The occurrence of these intermediates is attributed to the formation of highly hydrated networks whose stability is mainly based on weak interactions and the variability of the metal-containing pre-critical clusters. Their existence and compositional freedom are evidenced by electrospray ionization mass spectrometry (ESI-MS). Liquid intermediates in non-classical crystallisation pathways seem to be more common than assumed. PY - 2011 DO - https://doi.org/10.1039/c0nr00761g SN - 2040-3364 SN - 2040-3372 IS - 3 SP - 1158 EP - 1165 PB - RSC Publ. CY - Cambridge AN - OPUS4-23355 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Steers, E.B.M. A1 - Hoffmann, V. A1 - Unger, Wolfgang A1 - Paatsch, Wolfgang A1 - Wetzig, K. T1 - Influence of hydrogen on the analytical figures of merit of glow discharge optical emission spectroscopy - friend or foe? PY - 2003 DO - https://doi.org/10.1039/b305384a SN - 0267-9477 SN - 1364-5544 VL - 18 SP - 521 EP - 526 PB - Royal Society of Chemistry CY - London AN - OPUS4-2290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Steers, E.B.M. A1 - Hoffmann, V. A1 - Wetzig, K. T1 - The effect of small quantities of hydrogen on a glow discharge in neon. Comparison with the argon case N2 - In order to gain an insight into the numerous effects caused by the addition of hydrogen to an argon glow discharge, comparison experiments have been made with neon as carrier gas. In some cases the effects are diminished or even disappear. Using various bulk samples, such as copper, steel and titanium, sputtered in a neon glow discharge, the intensities of the analytical lines are affected by the presence of hydrogen in different ways from argon; the dependent parameter (the discharge current in this work) and the sputtering rate vary less than in argon. The crater shape and roughness are also affected and these effects are discussed qualitatively. Probably the most important spectral feature caused by hydrogen in the case of a discharge in argon is the emission of a continuous background. This does not appear in neon under similar discharge conditions and only weakly at high hydrogen concentrations. This supports the suggestion, made in previous work, that an effective quenching process of the argon metastables (11.55 and 11.72 eV) is Penning excitation of the hydrogen molecules, and subsequent decay to a repulsive state with emission of the continuum; in neon the energy match does not occur. It was found with neon, as with argon, that similar features occur as when hydrogen is introduced in different ways into the glow discharge: as a molecular gas contamination or as a constituent of the sample. Glow discharge mass spectrometry (GD-MS) experiments carried out with both argon and neon support the results obtained by optical emission spectrometry (OES) and provide further relevant information. PY - 2001 DO - https://doi.org/10.1039/b007527m SN - 0267-9477 SN - 1364-5544 VL - 16 SP - 43 EP - 49 PB - Royal Society of Chemistry CY - London AN - OPUS4-6887 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Hoffmann, V. A1 - Wetzig, K. A1 - Steers, E.B.M. T1 - Investigations of the effect of hydrogen in an argon glow discharge N2 - Clear evidence of the effects caused by hydrogen, introduced in different forms in an analytical glow discharge source (GDS) operated with argon, is presented for the different matrix elements copper, stainless steel, titanium, aluminium and silicon. When hydrogen is present even in small quantities in argon, not only are there significant changes in the emission line intensities of most elements (analyte and plasma species), but also new spectral features, such as emission bands of new compounds (hydrides of sputtered sample constituents) and a continuous background in the range ~220–440 nm. Moreover, the discharge current (the dependent parameter in our experiments) decreases with increasing hydrogen concentration. Different modes of hydrogen introduction, externally in gaseous form or sputtered as a sample constituent, cause very similar effects in terms of discharge current, line intensity (of analyte and plasma gas) and emission continua, which implies similar changes in the discharge processes in the two cases. The excitation of the hydrogen continuum appears to quench the population of the argon metastables (11.55 and 11.72 eV) and, consequently, other elementary processes in the plasma in which the argon metastables take part, but to a different extent for each analyte. PY - 2000 DO - https://doi.org/10.1039/b002367l SN - 0267-9477 SN - 1364-5544 IS - 15 SP - 1075 EP - 1080 PB - Royal Society of Chemistry CY - London AN - OPUS4-964 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Hoffmann, V. A1 - Wetzig, K. A1 - Steers, E.B.M. T1 - Emission spectra of copper and argon in an argon glow discharge containing small quantities of hydrogen N2 - The influence of hydrogen contained in a sample or otherwise introduced into a glow discharge source (GDS) is here extensively experimentally presented for the case of copper as a sample by means of the addition of small quantities of molecular hydrogen (<1% relative partial pressure) to the argon carrier gas. The progressive addition of molecular hydrogen causes different intensity changes particular to the individual lines of different species such as atomic (Cu I) and ionic (Cu II) copper, and also atomic (Ar I) and ionic (Ar II) argon. Some interesting features of the emission spectrum of hydrogen such as its line, band and even continuum spectrum are observed. It was also found that the depth resolution becomes worse even at very low concentrations of hydrogen. PY - 2000 DO - https://doi.org/10.1039/b001565m SN - 0267-9477 SN - 1364-5544 IS - 15 SP - 951 EP - 958 PB - Royal Society of Chemistry CY - London AN - OPUS4-965 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kaufmann, Felix E.D. A1 - Hoffmann, Marie C. A1 - Bachmann, Kai A1 - Veksler, Ilya V. A1 - Trumbull, Robert B. A1 - Hecht, Lutz T1 - Variations in composition, texture, and platinum group element mineralization in the lower group and middle group chromitites of the Northwestern Bushveld Complex, South Africa N2 - Small-scale variations in mineral chemistry, textures, and platinum group element (PGE) mineralization were investigated in the Lower and Middle Group chromitite layers LG6, LG6a, MG1, MG2, and MG2 II from vertical drill core profiles at the Thaba mine in the northwestern limb of the Bushveld Complex. We present detailed geochemical profiles of chromite composition and chromite crystal size distribution curves to shed light on the processes of chromite accumulation and textural modification as well as mineralization. Multiple samples within each layer were assayed for PGE concentrations, and the respective platinum group mineral association was determined by mineral liberation analysis (MLA). There is strong evidence for postcumulus changes in the chromitites. The crystal size distribution curves suggest that the primary chromite texture was coarsened by a combination of adcumulus growth and textural equilibration, while compaction of the crystal mush played only a minor role. Mineral compositions were also modified by postcumulus processes, but because of the very high modal amount of chromite and its local preservation in orthopyroxene oikocrysts, that phase retained much primary information. Vertical variations of chromite composition within chromitite layers and from one layer to another do not support the idea of chromite accumulation from crystal-rich slurries or crystal settling from a large magma chamber. Instead, we favor a successive buildup of chromitite layers by repeated injections of relatively thin layers of chromite-saturated magmas, with in situ crystallization occurring at the crystal mush-magma interface. The adcumulus growth of chromite grains to form massive chromitite required addition of Cr to the layers, which we attribute to downward percolation from the overlying magma. The PGE concentrations are elevated in all chromitite layers compared to adjacent silicate rocks and show a systematic increase upward from LG6 (avg 807 ppb Ir + Ru + Rh + Pt + Pd + Au) to MG2 II (avg 2,062 ppb). There are also significant internal variations in all layers, with enrichments at hanging and/or footwalls. The enriched nature of chromitites in PGEs compared to host pyroxenites is a General feature, independent of the layer thickness. The MLA results distinguish two principal groups of PGE mineral associations: the LG6, LG6, and MG1 are dominated by the malanite series, laurite, and PGE sulfarsenides, while the MG2 and MG2 II layers are characterized by laurite and PGE sulfides as well as Pt-Fe-Sn and PGE-Sb-Bi-Pb alloys. Differences in the PGE associations are attributed to postcumulus alteration of the MG2 and MG2 II layer, while the chromitites below, particularly LG6 and LG6a, contain a more pristine association. KW - Bushveld Complex KW - Chromitites KW - Platinum PY - 2019 DO - https://doi.org/10.5382/econgeo.4641 SN - 0361-0128 VL - 114 IS - 3 SP - 569 EP - 590 PB - Society of Economic Geologists AN - OPUS4-48145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Hoffmann, V. A1 - Steers, E.B.M. A1 - Griepentrog, Michael A1 - Dück, Alexander A1 - Beck, Uwe T1 - Round Robin exercise: Coated materials for glow discharge spectroscopy N2 - A Round Robin (RR) exercise on selected coated materials has been carried out with the aim of finding the optimal conditions for the analysis of nitride layers with GD-OES. Such pre-normative work is necessary for the evaluation of parallel development of the production of nitride layers as certified reference materials (CRMs). Two types of samples, Ti–N layer and V–N layer, respectively, with chemical compositions close to stoichiometry and a thickness of ~3 µm, deposited on a steel substrate, have been provided to the RR participants. Additionally, another type of sample, a (100 nm CrNi/100 nm Cu) multilayer (ML) stack deposited on silicon wafer has also been included in the RR. This sample can be used as a CRM for checking GD spectrometer conditions and it has been proved helpful in further development of GDS instrumentation and methodology. The RR exercise has been performed in the frame of the EC Thematic Network on Glow Discharge Spectroscopy for Spectrochemical Analysis (‘GDS-Net’). KW - Coated/Layered Reference Materials KW - Nitrides KW - Multilayer KW - GDS KW - Round Robin PY - 2006 DO - https://doi.org/10.1039/B513426A SN - 0267-9477 SN - 1364-5544 VL - 21 IS - 1 SP - 74 EP - 81 PB - Royal Society of Chemistry CY - London AN - OPUS4-11762 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -