TY - JOUR A1 - Bachmann, H. J. A1 - Bucheli, T. D. A1 - Dieguez-Alonso, A. A1 - Fabbri, D. A1 - Knicker, H. A1 - Schmidt, H.-P. A1 - Ulbricht, A. A1 - Becker, Roland A1 - Buscaroli, A. A1 - Buerge, D. A1 - Cross, A. A1 - Dickinson, D. A1 - Enders, A. A1 - Esteves, V.I. A1 - Evangelou, M. W. H. A1 - Fellet, G. A1 - Friedrich, K. A1 - Gasco Guerrero, G. A1 - Glaser, B. A1 - Hanke, U. M. A1 - Hanley, K. A1 - Hilber, I. A1 - Kalderis, D. A1 - Leifeld, J. A1 - Masek, O. A1 - Mumme, J. A1 - Paneque Carmona, M. A1 - Calvelo Pereira, R. A1 - Rees, F. A1 - Rombola, A. G. A1 - de la Rosa, J. M. A1 - Sakrabani, R. A1 - Sohi, S. A1 - Soja, G. A1 - Valagussa, M. A1 - Verheijen, F. A1 - Zehetner, F. T1 - Towards the standardization of biochar analysis: the COST action TD1107 interlaboratory comparison N2 - Biochar produced by pyrolysis of organic residues is increasingly used for soil amendment and many other applications. However, analytical methods for its physical and chemical characterization are yet far from being specifically adapted, optimized, and standardized. Therefore, COST Action TD1107 conducted an interlaboratory comparison in which 22 laboratories from 12 countries analyzed three different types of biochar for 38 physical–chemical parameters (macro- and microelements, heavy metals, polycyclic aromatic hydrocarbons, pH, electrical conductivity, and specific surface area) with their preferential methods. The data were evaluated in detail using professional interlaboratory testing software. Whereas intralaboratory repeatability was generally good or at least acceptable, interlaboratory reproducibility was mostly not (20% < mean reproducibility standard deviation < 460%). This paper contributes to better comparability of biochar data published already and provides recommendations to improve and harmonize specific methods for biochar analysis in the future. KW - Biochar KW - Analysis KW - Standardization KW - Ring test KW - Interlaboratory comparison PY - 2016 DO - https://doi.org/10.1021/acs.jafc.5b05055 SN - 0021-8561 SN - 1520-5118 VL - 64 IS - 2 SP - 513 EP - 527 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-35289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pott, U. A1 - Crasselt, Claudia A1 - Fobbe, N. A1 - Haist, M. A1 - Heinemann, M. A1 - Hellmann, S. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Lei, L. A1 - Li, R. A1 - Link, J. A1 - Lowke, D. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Nicia, D. A1 - Plank, J. A1 - Reißig, S. A1 - Schäfer, T. A1 - Schilde, C. A1 - Schmidt, Wolfram A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Strybny, B. A1 - Ukrainczyk, N. A1 - Wolf, J. A1 - Xiao, P. A1 - Stephan, D. T1 - Characterization data of reference materials used for phase II of the priority program DFG SPP 2005 “Opus Fluidum Futurum –Rheology of reactive, multiscale, multiphase construction materials” N2 - A thorough characterization of base materials is the prereq- uisite for further research. In this paper, the characterization data of the reference materials (CEM I 42.5 R, limestone pow- der, calcined clay and a mixture of these three components) used in the second funding phase of the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented under the aspects of chemical and min- eralogical composition as well as physical and chemical properties. The data were collected based on tests performed by up to eleven research groups involved in this cooperative program. KW - Portland cement KW - Limestone powder KW - Calcined clay KW - Sustainable cement KW - DFG SPP 2005 PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569913 DO - https://doi.org/10.1016/j.dib.2023.108902 VL - 47 SP - 1 EP - 19 PB - Elsevier AN - OPUS4-56991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Haist, M. A1 - Link, J. A1 - Nicia, D. A1 - Leinitz, Sarah A1 - Baumert, C. A1 - von Bronk, T. A1 - Cotardo, D. A1 - Eslami Pirharati, M. A1 - Fataei, S. A1 - Garrecht, H. A1 - Gehlen, C. A1 - Hauschildt, I. A1 - Ivanova, I. A1 - Jesinghausen, S. A1 - Klein, C. A1 - Krauss, H.-W. A1 - Lohaus, L. A1 - Lowke, D. A1 - Mazanec, O. A1 - Pawelczyk, S. A1 - Pott, U. A1 - Radebe, N. W. A1 - Riedmiller, J. J. A1 - Schmid, H.-J. A1 - Schmidt, Wolfram A1 - Secrieru, E. A1 - Stephan, D. A1 - Thiedeitz, M. A1 - Wilhelm, M. A1 - Mechtcherine, V. T1 - Interlaboratory study on rheological properties of cement pastes and reference substances: comparability of measurements performed with different rheometers and measurement geometries N2 - This paper presents the results of an interlaboratory study of the rheological properties of cement paste and ultrasound gel as reference substance. The goal was to quantify the comparability and reproducibility of measurements of the Bingham parameters yield stress and plastic viscosity when measured on one specific paste composition and one particular ultrasound gel in different laboratories using different rheometers and measurement geometries. The procedures for both in preparing the cement paste and carrying out the rheological measurements on cement paste and ultrasound gel were carefully defined for all of the study’s participants. Different conversion schemes for comparing the results obtained with the different measurement setups are presented here and critically discussed. The procedure proposed in this paper ensured a reasonable comparability of the results with a coefficient of variation for the yield stress of 27% and for the plastic viscosity of 24%, despite the individual measurement series’ having been performed in different labs with different rheometers and measurement geometries. KW - Rheometry KW - Rheology KW - Interlaboratory test KW - Test setup KW - Testing procedure KW - Cement paste KW - Ultrasound gel PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511220 DO - https://doi.org/10.1617/s11527-020-01477-w SN - 1871-6873 VL - 53 IS - 4 SP - 92 PB - Rilem AN - OPUS4-51122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lu, Z. A1 - Haist, M. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Leinitz, Sarah A1 - Link, J. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Plank, J. A1 - Schmidt, Wolfram A1 - Schilde, C. A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Stephan, D. T1 - Characterization data of reference cement CEM I 42.5 R used for Priority Program DFG SPP 2005 “Opus Fluidum Futurum - Rheology of reactive, multiscale, multiphase construction materials” N2 - A thorough characterization of starting materials is the precondition for further research, especially for cement, which contains various phases and presents quite a complex material for fundamental scientific investigation. In the paper at hand, the characterization data of the reference cement CEM I 42.5 R used within the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented from the aspects of chemical and mineralogical compositions as well as physical and chemical properties. The data were collected based on tests conducted by nine research groups involved in this cooperative program. For all data received, the mean values and the corresponding errors were calculated. The results shall be used for the ongoing research within the priority program. KW - Portland cement KW - Characterization KW - DFG SPP 2005 PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-500849 DO - https://doi.org/10.1016/j.dib.2019.104699 SN - 2352-3409 VL - 27 SP - 104699 PB - Elsevier Inc. AN - OPUS4-50084 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lu, Z. C. A1 - Haist, M. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Schmid, M. A1 - Kißling, P. A. A1 - Leinitz, Sarah A1 - Link, J. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Plank, J. A1 - Schmidt, Wolfram A1 - Schilde, C. A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Stephan, D. T1 - Characterization data of reference cement CEM III/A 42.5N used for priority program DFG SPP 2005 "Opus Fluidum Futurum - Rheology of reactive, multiscale, multiphase construction materials" N2 - Two types of cements were selected as the reference cement in the priority program 2005 of the German Research Foundation (DFG SPP 2005). A thorough characterization of CEM I 42.5 R has been made in a recent publication. In this paper, the characterization data of the other reference cement CEM III/A 42.5 N are presented from the aspects of chemical and mineralogical compositions as well as physical and chemical properties. The characterization data of the slag, which is the second main constituent of this specific cement besides the clinker, are presented independently. For all data received, the mean values and the corresponding errors were calculated. The data shall be used for the ongoing research within the priority program. Also, researchers from outside this priority program can benefit from these data if the same materials are used. KW - Cement KW - Slag KW - Characterization KW - DFG SPP 2005 PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568980 DO - https://doi.org/10.1016/j.dib.2020.105524 SN - 2352-3409 VL - 30 SP - 1 EP - 14 PB - Elsevier CY - Amsterdam AN - OPUS4-56898 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strüder, L. A1 - Hartmann, R. A1 - Holl, P. A1 - Ihle, S. A1 - Huth, M. A1 - Schmidt, J. A1 - Tham, Ch. A1 - Kanngießer, B. A1 - Baumann, J. A1 - Renno, A. A1 - Grenzer, J. A1 - Radtke, Martin A1 - Abboud, A. A1 - Pietsch, U. A1 - Soltau, H. T1 - High Speed, High Resolution imaging spectrometers based on pnCCDs for XRF and XRD applications N2 - For many years pnCCDs have been well known as X-ray detectors for spectroscopic imaging in many fields of science: X-Ray Fluorescence analysis (XRF), X-ray Diffraction (XRD) with light sources in large accelerator facilities as well as with laboratory light sources or with X-rays from celestial sources in X-ray astronomy. A brief introduction in GEXRF (Grazing Emission XRF) measurements with a laboratory laser produced plasma source will be given, PIXE (Particle Induced X-ray Emission) measurements and D2XRF (Double Dispersive X-Ray Fluorescence) and Slicing experiments with pnCCDs coupled to polycapillary optics performed at the BESSY synchrotron will be shown. Energy-dispersive Laue diffraction with ultra-hard X-rays for the analysis of defects in metals will conclude the overview of spectroscopic X-ray imaging measurements in the field of structure and dynamics of matter. KW - PnCCD KW - Synchrotron KW - XRF PY - 2016 DO - https://doi.org/10.1017/S1431927616001355 VL - 22 IS - S3 SP - 100 EP - 101 AN - OPUS4-38884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Raute, J. A1 - Schmidt, J. A1 - Bhadeliya, A. A1 - Rehmer, B. A1 - Olbricht, J. A1 - Jokisch, T. A1 - Biegler, M. A1 - Rethmeier, M. T1 - Investigation on seam quality and fatigue crack propagation in electron beam welded additive manufactured Inconel 939 N2 - Laser powder bed fusion of metals (PBF-LB/M) offers great potential for the production of new and spare parts for stationary gas turbines made of nickel superalloys such as Inconel 939 (IN939). In order to enable integration into existing assemblies and overcome design limitations, the additive manufacturing process chain must be expanded by suitable joining techniques. This study compares the electron beam welding of cast IN939 sheets and sheets produced additively using PBF-LB/M. The investigation focuses on the achievable seam quality with regard to geometric irregularities and internal defects in the form of liquation cracks on the microscale in the heat-affected zone. The evaluation of the welded samples shows no differences in the formation of the seam shape between the additively manufactured material and the cast material. For both materials, the highest quality category for beam-welded seams according to DIN EN ISO 13,919–1 was achieved at high welding speeds of 20 mm/s. Regardless of the manufacturing method, both materials show an increase in crack formation with increasing welding speed. However, due to its microstructure, the PBF-LB/M material exhibits significantly fewer microcracks overall. Final crack propagation tests on welded PBF-LB/M samples that were treated using HIP also show stable crack growth without sudden failure, which opens up potential for practical application. KW - Electron beam welding KW - Inconel 939 KW - PBF-LB/M KW - Liquation cracking KW - Fatigue crack propagation PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-657015 DO - https://doi.org/10.1016/j.jajp.2026.100389 SN - 2666-3309 VL - 13 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-65701 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Debatin, F. A1 - Behrens, K. A1 - Weber, J. A1 - Baburin, I. A. A1 - Thomas, A. A1 - Schmidt, J. A1 - Senkovska, I. A1 - Kaskel, S. A1 - Kelling, A. A1 - Hedin, N. A1 - Bacsik, Z. A1 - Leoni, S. A1 - Seifert, G. A1 - Jäger, Christian A1 - Günter, C. A1 - Schilde, U. A1 - Friedrich, A. A1 - Holdt, H.-J. T1 - An isoreticular family of microporous metal-organic frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate: syntheses, structures and properties N2 - We report on a new series of isoreticular frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate (IFP-1–4, IFP=imidazolate framework Potsdam) that form one-dimensional, microporous hexagonal channels. Varying R in the 2-substitued linker (R=Me (IFP-1), Cl (IFP-2), Br (IFP-3), Et (IFP-4)) allowed the channel diameter (4.0–1.7 Å), the polarisability and functionality of the channel walls to be tuned. Frameworks IFP-2, IFP-3 and IFP-4 are isostructural to previously reported IFP-1. The structures of IFP-2 and IFP-3 were solved by X-ray crystallographic analyses. The structure of IFP-4 was determined by a combination of PXRD and structure modelling and was confirmed by IR spectroscopy and 1H MAS and 13C CP-MAS NMR spectroscopy. All IFPs showed high thermal stability (345–400°C); IFP-1 and IFP-4 were stable in boiling water for 7 d. A detailed porosity analysis was performed on the basis of adsorption measurements by using various gases. The potential of the materials to undergo specific interactions with CO2 was investigated by measuring the isosteric heats of adsorption. The capacity to adsorb CH4 (at 298 K), CO2 (at 298 K) and H2 (at 77 K) at high pressure were also investigated. In situ IR spectroscopy showed that CO2 is physisorbed on IFP-1–4 under dry conditions and that both CO2 and H2O are physisorbed on IFP-1 under moist conditions. KW - Adsorption KW - Metal-organic frameworks KW - Microporous materials KW - N,O ligands KW - Zinc PY - 2012 DO - https://doi.org/10.1002/chem.201200889 SN - 0947-6539 SN - 1521-3765 VL - 18 IS - 37 SP - 11630 EP - 11640 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-27725 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bender, S. A1 - Göllner, J. A1 - Heyn, Andreas A1 - Heilmaier, M. A1 - Schmidt, J. ED - Kainer, K.U. T1 - Basic examinations of pre-treatment and coating of magnesium alloys T2 - 8th International conference on magnesium alloys and their applications CY - Weimar, Germany DA - 2009-10-26 KW - Magnesium KW - Korrosion KW - Beschichtung KW - Vorbehandlung KW - Elektrochemisches Rauschen PY - 2010 SN - 978-3-527-32732-4 SP - 1323 EP - 1330 PB - Wiley-VCH AN - OPUS4-20743 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kühling, J. A1 - Schmidt, J. A1 - Dahn, T. A1 - Niebergall, Ute A1 - Bogusch, G. T1 - Die kopferhaltende operative Versorgung der traumatischen medialen Schenkelhalsfraktur mit Großfragmentschrauben - eine biomechanische Prüfung N2 - Studienziel: Bei der zunehmenden Überalterung der Bevölkerung und der zunehmenden Inzidenz an hüftgelenknahen Oberschenkelfrakturen nimmt die Frage der Versorgung der medialen Schenkelhalsfraktur eine zunehmende Rolle ein. Vor allem aus Ungarn und den skandinavischen Ländern wird die kopferhaltende Therapie propagiert. Das Redislozieren dieser Frakturen und die Hüftkopfnekrose sind jedoch dagegenstehende Probleme. Methode: Ermutigt durch zwei theoretische mathematische Überlegungen wurden in einem biomechanischen Experiment zwei verschiedene Möglichkeiten der Verschraubung der medialen Schenkelhalsfraktur erprobt. Ergebnisse: Als Ergebnis zeigte sich, dass eine kopferhaltende Versorgung mit 2 kranial liegenden Schrauben und einer dreipunktabgestützten Schraube am Adam'schen Bogen deutliche biomechanische Vorteile hat gegenüber der herkömmlichen Verschraubung. Schlussfolgerung: Dies ermutigt uns, zunehmend die minimalinvasive und kopferhaltende Versorgung der medialen Schenkelhalsfraktur insbesondere bei Pauwels-I- und II-Verletzungen einzusetzen. KW - Mediale Schenkelhalsfraktur KW - Schraubenosteosynthese KW - Biomechanik KW - Medial hip fracture KW - Osteosynthesis with screw KW - Biomechanics PY - 2005 DO - https://doi.org/10.1055/s-2005-836807 SN - 0044-3220 VL - 143 SP - 412 EP - 418 PB - Thieme CY - Stuttgart AN - OPUS4-10755 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, J. A1 - Letsch, R. A1 - Kühling, J. A1 - Baranek, T. A1 - Niebergall, Ute A1 - Bogusch, G. T1 - Stability of Screw Fixation of Femoral Neck Fractures - A Biomechanical Trial N2 - With a growing percentage of elderly people in the population and, correspondingly, an increasing rate of fractures of the proximal femur, the question how to stabilize medial femoral-neck fractures is gaining increasing importance. Especially in Hungary and Scandinavian countries, femoral-head-preserving surgery is advocated. However, the main problems of this procedure are re-dislocation and necrosis of the femoral head. Encouraged by two theoretical mathematical considerations, a biomechanical experiment was performed to investigate two different methods of screw fixation of medial femoral-neck fractures. The results showed that a head-preserving internal fixation with two cranial screws and a three-point supported screw at the bottom of the neck had distinct biomechanical advantages compared to conventional screw fixation. This has encouraged us to more frequently perform this minimally invasive and head-preserving surgery in Pauwels I and II medial fractures of the femoral head. KW - Femoral neck fracture KW - Screw fixation KW - Biomechanical stability KW - Cadaver experiment KW - Mathematical model PY - 2005 DO - https://doi.org/10.1055/s-2005-836332 SN - 1618-971X VL - 13 IS - 2 SP - 76 EP - 81 PB - Thieme CY - Stuttgart AN - OPUS4-10843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kühling, J. A1 - Niebergall, Ute A1 - Calmez, D. A1 - Schnorr, W. A1 - Schmidt, J. T1 - Die distale Unterschenkelverriegelungsnagelung - eine statische Prüfung N2 - Studienziel: Zwei Nagelsysteme, zum einen der unaufgebohrte Tibianagel mit 3fach-Verriegelung in 2 Ebenen und großem Bolzenspiel (UTN® der Fa. Mathys®) mit der Möglichkeit von medial zweifach und von ventral einfach zu verriegeln und zum anderen der unaufgebohrte Tibianagel mit 3fach-Verriegelung in einer Ebene mit geringem Bolzenspiel (Targon®-Nagel der Fa. Aesculap®), der 3 mediale Verriegelungsmöglichkeiten besitzt, wurden im Biegeversuch statisch geprüft. Anatomisch besteht bei der ventralen Verriegelung immer die Verletzungsmöglichkeit von Sehnen, Nerven und Gefäßen. Andererseits besteht bei einem „höheren Bolzenspiel“ immer ein höherer Instabilitätsgrad. Inwieweit ist die Verriegelung in zwei Ebenen notwendig? Methode: Wir prüften statisch zwei intramedulläre Verriegelungssysteme an 8 Leichenknochen (matched pairs) in zwei Ebenen an einer Universalprüfmaschine der Firma Schenk-Trebel im Biegeversuch. Ergebnisse: Die Untersuchungsergebnisse zeigen, dass nicht die Bolzenlage, sondern das so genannte „Bolzenspiel“ für die Stabilität der distalen Fragmente entscheidend ist. Die Verriegelung sollte somit prinzipiell durch ein formschlüssiges winkelstabiles Bolzensystem möglich sein. PY - 2004 DO - https://doi.org/10.1055/s-2004-817964 SN - 0044-6173 SN - 1438-9436 SN - 0935-0705 VL - 34 SP - 71 EP - 77 PB - Thieme CY - Stuttgart AN - OPUS4-3533 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sprachmann, J. A1 - Wachsmuth, T. A1 - Bhosale, M. A1 - Burmeister, D. A1 - Smales, Glen Jacob A1 - Schmidt, M. A1 - Kochovski, Z. A1 - Grabicki, N. A1 - Wessling, R. A1 - List-Kratochvil, E. J. W. A1 - Esser, B. A1 - Dumele, O. T1 - Antiaromatic Covalent Organic Frameworks Based on Dibenzopentalenes N2 - Despite their inherent instability, 4n π systems have recently received significant attention due to their unique optical and electronic properties. In dibenzopentalene (DBP), benzanellation stabilizes the highly antiaromatic pentalene core, without compromising its amphoteric redox behavior or small HOMO−LUMO energy gap. However, incorporating such molecules in organic devices as discrete small molecules or amorphous polymers can limit the performance (e.g., due to solubility in the battery electrolyte solution or low internal surface area). Covalent organic frameworks (COFs), on the contrary, are highly ordered, porous, and crystalline materials that can provide a platform to align molecules with specific properties in a well-defined, ordered environment. We synthesized the first antiaromatic framework materials and obtained a series of three highly crystalline and porous COFs based on DBP. Potential applications of such antiaromatic bulk materials were explored: COF films show a conductivity of 4 × 10−8 S cm−1 upon doping and exhibit photoconductivity upon irradiation with visible light. Application as positive electrode materials in Li-organic batteries demonstrates a significant enhancement of performance when the antiaromaticity of the DBP unit in the COF is exploited in its redox activity with a discharge capacity of 26 mA h g−1 at a potential of 3.9 V vs. Li/Li+ . This work showcases antiaromaticity as a new design principle for functional framework materials. KW - SAXS KW - MOUSE KW - Covalent Organic Frameworks KW - Batteries PY - 2023 DO - https://doi.org/10.1021/jacs.2c10501 SP - 1 EP - 12 PB - ACS Publications AN - OPUS4-56958 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tötzke, C. A1 - Manke, I. A1 - Gaiselmann, G. A1 - Bohner, J. A1 - Müller, Bernd R. A1 - Kupsch, Andreas A1 - Hentschel, Manfred P. A1 - Schmidt, V. A1 - Banhart, J. A1 - Lehnert, W. T1 - A dedicated compression device for high resolution X-ray tomography of compressed gas diffusion layers N2 - We present an experimental approach to study the three-dimensional microstructure of gas diffusion layer (GDL) materials under realistic compression conditions. A dedicated compression device was designed that allows for synchrotron-tomographic investigation of circular samples under well-defined compression conditions. The tomographic data provide the experimental basis for stochastic modeling of nonwoven GDL materials. A plain compression tool is used to study the fiber courses in the material at different compression stages. Transport relevant geometrical parameters, such as porosity, pore size, and tortuosity distributions, are exemplarily evaluated for a GDL sample in the uncompressed state and for a compression of 30 vol.%. To mimic the geometry of the flow-field, we employed a compression punch with an integrated channel-rib-profile. It turned out that the GDL material is homogeneously compressed under the ribs, however, much less compressed underneath the channel. GDL fibers extend far into the channel volume where they might interfere with the convective gas transport and the removal of liquid water from the cell. KW - PEM fuel cell KW - Gas diffusion layer (GDL) KW - Compression device KW - X-ray tomography KW - Synchrotron KW - Tortuosity PY - 2015 DO - https://doi.org/10.1063/1.4918291 SN - 0034-6748 SN - 1089-7623 VL - 86 IS - 4 SP - 043702-1 EP - 043702-6 PB - American Institute of Physics CY - Melville, NY, USA AN - OPUS4-33081 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Carvello, J. M. F. A1 - Carvalho Fontes, W. A1 - de Azevedo, C. F. A1 - Brigolini, G. J. A1 - Schmidt, Wolfram A1 - Fiorotti Peixoto, R. A. T1 - Enhancing the eco-efficiency of concrete using engineered recycled mineral admixtures and recycled aggregates N2 - Non-conventional densely packed concrete mixtures are proposed and evaluated in this paper using engineered recycled mineral admixtures and recycled aggregates obtained from steel slag, quartz mining tailings, and quartzite mining tailings. High fines content sand-concretes containing coarser- and finer-than-cement recycled powders were designed to obtain blends with broader particle-size ranges and improved packing density. As a result, compressive strength up to 99 MPa, cement intensity up to 2.33 kg/m³/MPa, and consumption of recycled material up to 95 vol% were obtained. Compressive strengths up to 66 MPa and cement intensity up to 2.34 kg/m³/MPa were also obtained with the addition of coarse aggregates to such sand-concrete mixtures, with consumption of recycled material up to 96.5%. The results launch new insights on the role of recycled admixtures and aggregates on the mixture design of cement-based composites regarding efficiency improvement and technological performance. KW - Low-cement concrete KW - Recycled mineral admixture KW - Basic oxygen furnace slag KW - Quartzite mining tailing KW - Packing density PY - 2020 DO - https://doi.org/10.1016/j.jclepro.2020.120530 VL - 257 SP - 1 EP - 12 PB - Elsevier AN - OPUS4-58401 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmidt, Wolfram A1 - Cunnigham, P. R. A1 - Shaba, A. F. A1 - Olonade, K. A. A1 - Ndawula, J. A1 - Tawiah, A. T. A1 - Marangu, J. M. A1 - Tlhatlha, Pheladi A1 - Obeng, E. ED - Banhia, N. T1 - Informal Sector Inclusion in Sustainable Concrete Construction in Africa N2 - Concrete used as a construction material is inevitable in Africa’s rapid urban growth, despite its significant contribution to carbon emissions. Hence, best practice concrete with reduced Portland cement clinker needs to be applied. The highly informal nature ofAfrica’s construction sector could impede the implementation of sustainable concrete construction. Although urgent need for economisation unintentionally often leads informal actors to operate according to circularity principles, the sector lacks awareness of climate challenges and incentives for adopting climate-friendly materials and technologies. In addition, the informal sector is prone to fraudulent adulterated materials and components causing challenges for safe and durable construction. The authors elaborate on the crucial role of the informal sector in driving sustainable construction forward, despite the lack of policies and disinterest from regulatory bodies. Solutions through education, communication, and quality control are proposed and discussed. T2 - 77th RILEM Annual Week and the 1st Interdisciplinary Symposium on Smart & Sustainable Infrastructures (ISSSI 2023) CY - Vancouver, Canada DA - 04.09.2023 KW - Cement testing KW - Hydration KW - Economic development KW - Informal sector KW - Cement chemistry PY - 2024 SN - 978-3-031-53391-4 DO - https://doi.org/10.1007/978-3-031-53389-1_47 VL - 48 SP - 506 EP - 520 PB - Springer Nature Switzerland AG CY - Schweiz AN - OPUS4-61586 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Franco de Carvalho, J. M. A1 - Defàveri, K- A1 - Castro Mendes, J. A1 - Schmidt, Wolfram A1 - Kühne, Hans-Carsten A1 - Fiorotti Peixoto, R. A. T1 - Influence of particle size-designed recycled mineral admixtures on the properties of cement-based composites N2 - In this work, engineered recycled mineral admixtures were obtained from four different industrial residues: basic oxygen furnace slag, iron ore tailings, quartz mining tailings and quartzite mining tailings. The grinding performance was evaluated in two different programs and the characterization included chemical and mineralogical composition, particle morphology, and physical properties. Performance evaluations were carried out in blended pastes and mortars, including flow properties, hydration kinetics, soundness, pozzolanic activity, and compressive strength. Coarser-than-cement admixtures allowed better flow performance, greater dimensional stability and more economical production, while finer-thancementn admixtures improved mechanical performance by both filler effect and cementing activity. KW - Engineered recycled mineral admixtures KW - Rheology KW - Hydration kinetics KW - Basic oxygen furnace slag KW - Iron ore tailings KW - Mining tailings PY - 2021 DO - https://doi.org/10.1016/j.conbuildmat.2020.121640 SN - 0950-0618 VL - 272 SP - 1 EP - 13 PB - Elsevier Ltd. AN - OPUS4-58255 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wolf, M. E. A1 - Vickery, W. M. A1 - Swift-Ramirez, W. A1 - Arnold, A. M. A1 - Orlando, J. D. A1 - Schmidt, S. J. A1 - Liu, Y. A1 - Er, Jasmin A1 - Schusterbauer, Robert A1 - Ahmed, R. A1 - Nickl, Philip A1 - Radnik, Jörg A1 - Donskyi, Ievgen A1 - Sydlik, S. A. T1 - The Mitsunobu reaction for the gentle covalent attachment of biomolecules to graphene oxide N2 - Graphene oxide (GO) has emerged as a promising biomaterial as it is easily and cheaply synthesized, strong, cytocompatible, osteoinductive, and has a well-characterized aqueous degradation pathway. It is also a great substrate for functionalization with biomolecules such as proteins, peptides, and small molecules that can enhance or add bioactivity. Covalent chemical linkages as opposed to typical noncovalent association methods are preferable so that the biomolecules do not quickly diffuse away or face replacement by other proteins, which is critical in long time scale applications like bone regeneration. However, covalent chemistry tends to carry a drawback of harsh reaction conditions that can damage the structure, conformation, and therefore function of a delicate biomolecule like a protein. Here, the Mitsunobu reaction is introduced as a novel method of covalently attaching proteins to graphene oxide. It features gentle reaction conditions and has the added benefit of utilizing the plentiful basal plane alcohol functionalities on graphene oxide, allowing for high yield protein functionalization. The amino acid Glycine (G), the protein bovine serum albumin (BSA), and the small molecule SVAK-12 are utilized to create the three Mitsunobu Graphene (MG) materials G-MG, BSA-MG, and SVAK-MG that demonstrate the wide applicability of this functionalization method. KW - Graphene oxide KW - Mitsunobu reaction KW - Covalent attachment KW - Bovine serum albumin KW - Macrophage polarization KW - Osteogenesis PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630483 DO - https://doi.org/10.1016/j.carbon.2025.120221 VL - 238 SP - 1 EP - 15 PB - Elsevier Ltd. AN - OPUS4-63048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Göbel, M. A1 - Kirsch, S. A1 - Schwarze, L: A1 - Schmidt, L. A1 - Scholz, H. A1 - Haußmann, J. A1 - Klages, M. A1 - Scholta, J. A1 - Markötter, Henning A1 - Alrwashdeh, S. A1 - Manke, I. A1 - Müller, Bernd R. T1 - Transient limiting current measurements for characterization of gas diffusion layers N2 - The water management in proton exchange membrane fuel cells (PEMFC) is strongly influenced by the design of the gas diffusion layers (GDL). Limiting current measurements in small-scale cells operating at high stoichiometries are useful to determine the oxygen transport resistance. The oxygen transport resistance increases, once water condenses inside the GDL. In this study a new electrochemical method for voltage loss estimation of GDL induced oxygen transport losses are presented. This new method, referred to as “transient limiting current” (TLC), is compared with the literature method. TLC allows a direct estimation of oxygen transport resistance at an arbitrarily conditioned state. This study also presents a case study of liquid water visualization of a PEM fuel cell with varying GDLs types. With the help of quasi in-situ synchrotron X-ray computed tomography and time resolved radiography measurements we investigate appearance and distribution of liquid water inside the GDLs under limiting current conditions. KW - In-situ characterization of GDLs KW - In-situ synchrotron X-ray computed tomography KW - In-situ synchrotron X-ray radiography KW - BAMline PY - 2018 DO - https://doi.org/10.1016/j.jpowsour.2018.09.003 SN - 0378-7753 SN - 1873-2755 VL - 402 SP - 237 EP - 245 PB - Elsevier B.V. AN - OPUS4-46552 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zakel, S. A1 - Schröder, Volkmar A1 - Askar, Enis A1 - Gabel, D. A1 - Hirsch, W. A1 - Kleinert, J. A1 - Krause, U. A1 - Krietsch, Arne A1 - Meistes, J. A1 - Sachtleben, A. A1 - Schmidt, Martin T1 - Sicherheitstechnische Kenngrößen des Explosionsschutzes von hybriden Stoffgemischen - Normungsfähige Bestimmungsverfahren N2 - In diesem Verbundvorhaben werden standardisierte Messverfahren für hybride Gemische erarbeitet, die der Bestimmung sicherheitstechnischer Kenngrößen des Explosionsschutzes dienen. Unter einem hybriden Gemisch wird dabei ein mehrphasiges System aus Brenngas oder brennbarem Dampf, sowie Luft und brennbarem Staub verstanden. Die Veröffentlichung der Ergebnisse erfolgt in einem Abschlussbericht und als DIN-Spezifikation (DIN SPEC). Diese DIN SPEC versetzt Prüfinstitute und Industrie in die Lage, Explosionsgefahren beim Betrieb technischer Anlagen mit hybriden Gemischen einzuschätzen und damit Prozesse sowohl sicherer als auch effizienter zu steuern. Dieses Projekt wird im Rahmen des WIPANOProgramms (Wissens- und Technologietransfer durch Patente und Normen) vom BMWi gefördert. T2 - 14. Fachtagung Anlagen-, Arbeits- und Umweltsicherheit CY - Köthen, Germany DA - 07.11.2019 KW - Explosionsschutz KW - Sicherheitstechnische Kenngrößen KW - Hybride Gemische KW - Normung PY - 2019 SN - 978-3-89746-220-5 SP - 73 CY - Frankfurt am Main AN - OPUS4-49954 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tötzke, C. A1 - Gaiselmann, G. A1 - Osenberg, M. A1 - Bohner, J. A1 - Arlt, Tobias A1 - Markötter, Henning A1 - Hilger, A. A1 - Wieder, F. A1 - Kupsch, Andreas A1 - Müller, Bernd R. A1 - Hentschel, Manfred P. A1 - Banhart, J. A1 - Schmidt, V. A1 - Lehnert, W. A1 - Manke, I. T1 - Three-dimensional study of compressed gas diffusion layers using synchrotron X-ray imaging N2 - We present a synchrotron X-ray tomographic study on the morphology of carbon fiber-based gas diffusion layer (GDL) material under compression. A dedicated compression device is used to provide well-defined compression conditions. A flat compression punch is employed to study the fiber geometry at different degrees of compression. Transport relevant geometrical parameters such as porosity, pore size and tortuosity distributions are calculated. The geometric properties notably change upon compression which has direct impact on transport conditions for gas and fluid flow. The availability of broad 3D paths, which are most important for the transport of liquid water from the catalyst layer through the GDL, is markedly reduced after compression. In a second experiment, we study the influence of the channel-land-pattern of the flow-field on shape and microstructure of the GDL. A flow-field compression punch is employed to reproduce the inhomogeneous compression conditions found during fuel cell assembly. While homogenously compressed underneath the land the GDL is much less and inhomogeneously compressed under the channel. The GDL material extends far into the channel volume where it can considerably influence gas and fluid flow. Loose fiber endings penetrate deeply into the channel and form obstacles for the discharge of liquid water droplets. KW - Synchrotron X-ray tomography KW - Gas diffusion layer (GDL) KW - Microstructure KW - Water transport path KW - Pore size analysis KW - Geometrical tortuosity PY - 2014 DO - https://doi.org/10.1016/j.jpowsour.2013.12.062 SN - 0378-7753 VL - 253 SP - 123 EP - 131 PB - Elsevier CY - Amsterdam [u.a.] AN - OPUS4-29979 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Henning, L. M. A1 - Müller, J. T. A1 - Smales, Glen Jacob A1 - Pauw, Brian Richard A1 - Schmidt, J. A1 - Bekheet, M. F. A1 - Gurlo, A. A1 - Simon, U. T1 - Hierarchically porous and mechanically stable monoliths from ordered mesoporous silica and their water filtration potential N2 - Mechanically stable structures with interconnected hierarchical porosity combine the benefits of both small and large pores, such as high surface area, pore volume, and good mass transport capabilities. Hence, lightweight micro-/meso-/macroporous monoliths are prepared from ordered mesoporous silica COK-12 by means of spark plasma sintering (SPS, S-sintering) and compared to conventionally (C-) sintered monoliths. A multi-scale model is developed to fit the small angle X-ray scattering data and obtain information on the hexagonal lattice parameters, pore sizes from the macro to the micro range, as well as the dimensions of the silica population. For both sintering techniques, the overall mesoporosity, hexagonal pore ordering, and amorphous character are preserved. The monoliths' porosity (77–49%), mesopore size (6.2–5.2 nm), pore volume (0.50–0.22 g cm-3 ), and specific surface area (451–180 m2 g-1) decrease with increasing processing temperature and pressure. While the difference in porosity is enhanced, the structural parameters between the C-and S-sintered monoliths are largely converging at 900 C, except for the mesopore size and lattice parameter, whose dimensions are more extensively preserved in the S-sintered monoliths, however, coming along with larger deviations from the theoretical lattice. Their higher mechanical properties (biaxial strength up to 49 MPa, 724 MPa HV 9.807 N) at comparable porosities and ability to withstand ultrasonic treatment and dead-end filtration up to 7 bar allow S-sintered monoliths to reach a high permeance (2634 L m-2 h-1 bar-1), permeability (1.25 x 10^-14 m2), and ability to reduce the chemical oxygen demand by 90% during filtration of a surfactant-stabilized oil in water emulsion, while indicating reasonable resistance towards fouling. KW - SAXS KW - Hierarchically porous KW - Silica KW - Water filtration PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555928 DO - https://doi.org/10.1039/D2NA00368F SN - 2516-0230 SP - 1 EP - 17 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-55592 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ganose, Alex M. A1 - Sahasrabuddhe, Hrushikesh A1 - Asta, Mark A1 - Beck, Kevin A1 - Biswas, Tathagata A1 - Bonkowski, Alexander A1 - Bustamante, Joana A1 - Chen, Xin A1 - Chiang, Yuan A1 - Chrzan, Daryl C. A1 - Clary, Jacob A1 - Cohen, Orion A. A1 - Ertural, Christina A1 - Gallant, Max C. A1 - George, Janine A1 - Gerits, Sophie A1 - Goodall, Rhys E. A. A1 - Guha, Rishabh D. A1 - Hautier, Geoffroy A1 - Horton, Matthew A1 - Inizan, T. J. A1 - Kaplan, Aaron D. A1 - Kingsbury, Ryan S. A1 - Kuner, Matthew C. A1 - Li, Bryant A1 - Linn, Xavier A1 - McDermott, Matthew J. A1 - Mohanakrishnan, Rohith Srinivaas A1 - Naik, Aakash A. A1 - Neaton, Jeffrey B. A1 - Parmar, Shehan M. A1 - Persson, Kristin A. A1 - Petretto, Guido A1 - Purcell, Thomas A. R. A1 - Ricci, Francesco A1 - Rich, Benjamin A1 - Riebesell, Janosh A1 - Rignanese, Gian-Marco A1 - Rosen, Andrew S. A1 - Scheffler, Matthias A1 - Schmidt, Jonathan A1 - Shen, Jimmy-Xuan A1 - Sobolev, Andrei A1 - Sundararaman, Ravishankar A1 - Tezak, Cooper A1 - Trinquet, Victor A1 - Varley, Joel B. A1 - Vigil-Fowler, Derek A1 - Wang, Duo A1 - Waroquiers, David A1 - Wen, Mingjian A1 - Yang, Han A1 - Zheng, Hui A1 - Zheng, Jiongzhi A1 - Zhu, Zhuoying A1 - Jain, Anubhav T1 - Atomate2: Modular workflows for materials science N2 - High-throughput density functional theory (DFT) calculations have become a vital element of computational materials science, enabling materials screening, property database generation, and training of “universal” machine learning models. While several software frameworks have emerged to support these computational efforts, new developments such as machine learned force fields have increased demands for more flexible and programmable workflow solutions. This manuscript introduces atomate2, a comprehensive evolution of our original atomate framework, designed to address existing limitations in computational materials research infrastructure. Key features include the support for multiple electronic structure packages and interoperability between them, along with generalizable workflows that can be written in an abstract form irrespective of the DFT package or machine learning force field used within them. Our hope is that atomate2's improved usability and extensibility can reduce technical barriers for high-throughput research workflows and facilitate the rapid adoption of emerging methods in computational material science. KW - Automation KW - Materials design KW - DFT workflows KW - Phonons KW - Thermal conductivity KW - Bonding analysis PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-635759 DO - https://doi.org/10.1039/d5dd00019j SN - 2635-098X SP - 1 EP - 30 PB - Royal Society of Chemistry (RSC) CY - Cambridge AN - OPUS4-63575 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kapoor, M. A1 - Overgaard Christensen, Ch. A1 - Wittrup Schmidt, J. A1 - Dalsgaard Sørensen, J. A1 - Thöns, Sebastian T1 - Decision analytic approach for the reclassification of concrete bridges by using elastic limit information from proof loading N2 - Reclassification of bridges, i.e., a change in load rating, using reliability-based methods and a direct update with proof load information has been presented by many authors. However, bridge reclassification has hardly been studied from a decision analytic perspective, i.e., with quantification of the risks and benefits of different classification choices, and the expected benefit gain from proof loading. We derive, explain and exemplify a decision analytic approach for bridge reclassification along with models for (1) elastic and ultimate capacity and their adaptation with proof load information, (2) proof load information with classification outcomes accounting for target reliabilities and, (3) utilities including socio-economic benefits from reclassification. The approach and models are exemplified with a case study based on reclassification of bridges with a low existing classification. Decision rules, for practical use by a highway authority to find the optimal classification, are identified and documented based on: (1) the measurement of the capacity at elastic limit by proof loading, (2) the bridge reclassification benefits, and, (3) the required annual reliability level. From a Value of Information analysis, it is concluded that the proof load information is highly valuable for reclassification in cases of high socio-economic benefits and high reliability requirements. KW - Proof loading KW - Structural reliability KW - Value of information KW - Decision analysis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596845 DO - https://doi.org/10.1016/j.ress.2022.109049 SN - 0951-8320/ VL - 232 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-59684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ganose, Alex M. A1 - Sahasrabuddhe, Hrushikesh A1 - Asta, Mark A1 - Beck, Kevin A1 - Biswas, Tathagata A1 - Bonkowski, Alexander A1 - Bustamante, Joana A1 - Chen, Xin A1 - Chiang, Yuan A1 - Chrzan, Daryl C. A1 - Clary, Jacob A1 - Cohen, Orion A. A1 - Ertural, Christina A1 - Gallant, Max C. A1 - George, Janine A1 - Gerits, Sophie A1 - Goodall, Rhys E. A. A1 - Guha, Rishabh D. A1 - Hautier, Geoffroy A1 - Horton, Matthew A1 - Inizan, T. J. A1 - Kaplan, Aaron D. A1 - Kingsbury, Ryan S. A1 - Kuner, Matthew C. A1 - Li, Bryant A1 - Linn, Xavier A1 - McDermott, Matthew J. A1 - Mohanakrishnan, Rohith Srinivaas A1 - Naik, Aakash A. A1 - Neaton, Jeffrey B. A1 - Parmar, Shehan M. A1 - Persson, Kristin A. A1 - Petretto, Guido A1 - Purcell, Thomas A. R. A1 - Ricci, Francesco A1 - Rich, Benjamin A1 - Riebesell, Janosh A1 - Rignanese, Gian-Marco A1 - Rosen, Andrew S. A1 - Scheffler, Matthias A1 - Schmidt, Jonathan A1 - Shen, Jimmy-Xuan A1 - Sobolev, Andrei A1 - Sundararaman, Ravishankar A1 - Tezak, Cooper A1 - Trinquet, Victor A1 - Varley, Joel B. A1 - Vigil-Fowler, Derek A1 - Wang, Duo A1 - Waroquiers, David A1 - Wen, Mingjian A1 - Yang, Han A1 - Zheng, Hui A1 - Zheng, Jiongzhi A1 - Zhu, Zhuoying A1 - Jain, Anubhav T1 - Correction: Atomate2: Modular workflows for materials science N2 - Correction for “Atomate2: modular workflows for materials science” by Alex M. Ganose et al., Digital Discovery, 2025, 4, 1944–1973, https://doi.org/10.1039/D5DD00019J. PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640297 DO - https://doi.org/10.1039/d5dd90036k SN - 2635-098X SP - 1 EP - 2 PB - Royal Society of Chemistry (RSC) CY - Cambridge AN - OPUS4-64029 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Forler, D. A1 - Schmidt, J. P. A1 - Staude, Andreas T1 - Ein Becken aus Beckentin! - Fund des Monats Mai 2016 N2 - Bronzezeitlicher Hortfund in Mecklenburg-Vorpommern mit CT-Untersuchung an der BAM KW - Computertomographie KW - Hortfund KW - Bronzezeit KW - Mecklenburg-Vorpommern PY - 2016 UR - http://www.kulturwerte-mv.de/cms2/LAKD1_prod/LAKD1/de/Landesarchaeologie/Fund_des_Monats/index.jsp SP - 1 EP - 3 CY - Schwerin AN - OPUS4-36163 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Wilrich, Cordula A1 - Schröder, Volkmar A1 - Brandes, E. A1 - Schmidt, Martin A1 - Wandrey, Peter-Andreas A1 - Mix, K.-H. A1 - Wehrstedt, Klaus-Dieter A1 - Bender, H. A1 - Stephan, U. A1 - Eberz, A. A1 - Steinbach, J. A1 - Stoessel, F. T1 - Plant and process safety - 2. Hazardous materials and process conditions N2 - "Ullmann's Encyclopedia of Industrial Chemistry" is the benchmark reference in chemistry and chemical and life science engineering, covering inorganic and organic chemicals, advanced materials, pharmaceuticals, polymers and plastics, metals and alloys, biotechnology and biotechnological products, food chemistry, process engineering and unit operations, analytical methods, environmental protection, and much more. The present article is part of the topic collection "Environmental Protection and Industrial Safety". It covers plant and process safety, focusing on hazardous materials and process conditions. KW - Flammable gases and vapors KW - Combustibility of liquids KW - Dust explosions KW - Explosive condensed substances KW - Harmful effects of substances KW - Exothermic and pressure-inducing chemical reactions PY - 2012 SN - 978-3-527-30673-2 DO - https://doi.org/10.1002/14356007.q20_q01 SP - 1 EP - 50 PB - Wiley-VCH CY - Weinheim AN - OPUS4-58108 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Ballio, F. A1 - Chatzi, E. A1 - Cigada, A. A1 - Darò, P. A1 - Elfgren, L. A1 - Gentile, C. A1 - Górski, M. A1 - Küttenbaum, Stefan A1 - Limongelli, M. P. A1 - Mancini, G. A1 - Oliveira, S. A1 - Rasol, M. A1 - Schmidt, F. A1 - Shan, J. A1 - Sousa, H. A1 - Torrent, R. A1 - Ueda, T. A1 - Verstrynge, E. T1 - Chapter 6: Case studies N2 - This chapter contains a selection of case studies that show the implementation of the methods and tools that have been described in the previous chaprters of fib Bulletin 109 on actual large-scale structures. KW - Structural engineering KW - Structural Health Monitoring KW - Non-destructive testing KW - Static and dynamic reassessment KW - Existing structures PY - 2023 SN - 978-2-88394-172-4 DO - https://doi.org/10.35789/fib.BULL.0109.Ch06 SN - 1562-3610 VL - fib Bulletin 109 SP - 104 EP - 126 PB - Fédération internationale du béton (fib) CY - Lausanne AN - OPUS4-59341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jablonka, Kevin Maik A1 - Ai, Qianxiang A1 - Al-Feghali, Alexander A1 - Badhwar, Shruti A1 - Bocarsly, Joshua D. A1 - Bran, Andres M. A1 - Bringuier, Stefan A1 - Brinson, L. Catherine A1 - Choudhary, Kamal A1 - Circi, Defne A1 - Cox, Sam A1 - de Jong, Wibe A. A1 - Evans, Matthew L. A1 - Gastellu, Nicolas A1 - Genzling, Jerome A1 - Gil, María Victoria A1 - Gupta, Ankur K. A1 - Hong, Zhi A1 - Imran, Alishba A1 - Kruschwitz, Sabine A1 - Labarre, Anne A1 - Lála, Jakub A1 - Liu, Tao A1 - Ma, Steven A1 - Majumdar, Sauradeep A1 - Merz, Garrett W. A1 - Moitessier, Nicolas A1 - Moubarak, Elias A1 - Mouriño, Beatriz A1 - Pelkie, Brenden A1 - Pieler, Michael A1 - Ramos, Mayk Caldas A1 - Ranković, Bojana A1 - Rodriques, Samuel G. A1 - Sanders, Jacob N. A1 - Schwaller, Philippe A1 - Schwarting, Marcus A1 - Shi, Jiale A1 - Smit, Berend A1 - Smith, Ben E. A1 - Van Herck, Joren A1 - Völker, Christoph A1 - Ward, Logan A1 - Warren, Sean A1 - Weiser, Benjamin A1 - Zhang, Sylvester A1 - Zhang, Xiaoqi A1 - Zia, Ghezal Ahmad Jan A1 - Scourtas, Aristana A1 - Schmidt, K. J. A1 - Foster, Ian A1 - White, Andrew D. A1 - Blaiszik, Ben T1 - 14 examples of how LLMs can transform materials science and chemistry: a reflection on a large language model hackathon N2 - Large-language models (LLMs) such as GPT-4 caught the interest of many scientists. Recent studies suggested that these models could be useful in chemistry and materials science. To explore these possibilities, we organized a hackathon. This article chronicles the projects built as part of this hackathon. Participants employed LLMs for various applications, including predicting properties of molecules and materials, designing novel interfaces for tools, extracting knowledge from unstructured data, and developing new educational applications. The diverse topics and the fact that working prototypes could be generated in less than two days highlight that LLMs will profoundly impact the future of our fields. The rich collection of ideas and projects also indicates that the applications of LLMs are not limited to materials science and chemistry but offer potential benefits to a wide range of scientific disciplines. KW - Large Language model KW - Hackathon KW - Concrete KW - Prediction KW - Inverse Design KW - Orchestration PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589961 DO - https://doi.org/10.1039/d3dd00113j VL - 2 IS - 5 SP - 1233 EP - 1250 PB - Royal Society of Chemistry (RSC) AN - OPUS4-58996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, M. A1 - Schlingmann, T. A1 - Schmidt, J. A1 - Bettge, Dirk A1 - Hilgenberg, Kai A1 - Binder, M. A1 - Klöden, B. T1 - A Round Robin Test To Investigate The Printing Quality Of PBF LB/M Processed AlSi10Mg N2 - When it comes to higher accuracies, new technologies and real applications in additive manufacturing, there is one topic which cannot be avoided: The material response on the chosen processing parameters and its agreement and correspondence with literature data of the wrought material grade counterpart. In industrial Additive Manufacturing (AM) standards in terms of printing parameters, protection gas atmospheres or powder handling instructions are not obligatory. Therefore, the question must be answered whether the AM process is reproducible and reliable over different printing companies. This was the motivation to realize a round robin test between 8 European printing companies and academic partners. The consortium had printed and tested fatigue and tensile testing bars under plant-specific conditions. A commonly used cast aluminum alloy, AlSi10Mg, was chosen as test material for the PBF-LB/M process. Differences of the results between the partners and the scatter itself were discussed in detail. T2 - World PM2022 CY - Lyon, France DA - 09.10.2022 KW - Additive manufacturing KW - AlSi10Mg KW - Laser powder bed fusion KW - Round robin KW - Reproducibility PY - 2022 AN - OPUS4-56303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, M. A1 - Schlingmann, T. A1 - Schmidt, J. A1 - Bettge, Dirk A1 - Hilgenberg, Kai A1 - Binder, M. A1 - Klöden, B. T1 - A Round Robin Test To Investigate The Printing Quality Of PBF-LB/M Processed AlSi10Mg N2 - When it comes to higher accuracies, new technologies and real applications in additive manufacturing, there is one topic which cannot be avoided: The material response on the chosen processing parameters and its agreement and correspondence with literature data of the wrought material grade counterpart. In industrial Additive Manufacturing (AM) standards in terms of printing parameters, protection gas atmospheres or powder handling instructions are not obligatory. Therefore, the question must be answered whether the AM process is reproducible and reliable over different printing companies. This was the motivation to realize a round robin test between 8 European printing companies and academic partners. The consortium had printed and tested fatigue and tensile testing bars under plant-specific conditions. A commonly used cast aluminum alloy, AlSi10Mg, was chosen as test material for the PBF-LB/M process. Differences of the results between the partners and the scatter itself were discussed in detail. T2 - World PM2022 CY - Lyon, France DA - 09.10.2022 KW - Additive manufacturing KW - Round robin KW - Reproducibility KW - Laser powder bed fusion KW - AlSi10Mg PY - 2022 SN - 978-1-899072-54-5 SP - 1 EP - 10 PB - European Powder Metallurgy Association (EPMA) AN - OPUS4-56304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schneider, M. A1 - Bettge, Dirk A1 - Hilgenberg, Kai A1 - Binder, M. A1 - Dollmeier, K. A1 - Dreyer, M. A1 - Klöden, B. A1 - Schlingmann, T. A1 - Schmidt, J. T1 - Reproducibility and Scattering in Additive Manufacturing: Results from a Round Robin on PBF-LB/M AlSi10Mg Alloy T1 - Reproduzierbarkeit und Streuung bei der additiven Fertigung: Ergebnisse eines Ringversuchs mit einer PBF-LB/M AlSi10Mg-Legierung N2 - The round robin test investigated the reliability users can expect for AlSi10Mg additive manufactured specimens by laser powder bed fusion through examining powder quality, process parameter, microstructure defects, strength and fatigue. Besides for one outlier, expected static material properties could be found. Optical microstructure inspection was beneficial to determine true porosity and porosity types to explain the occurring scatter in properties. Fractographic analyses reveal that the fatigue crack propagation starts at the rough as-built surface for all specimens. Statistical analysis of the scatter in fatigue using statistical derived safety factors concludes that at a stress of 36.87 MPa the fatigue limit of 107 cycles could be reached for all specimen with a survival probability of 99.999 %. N2 - Im Rahmen eines Ringversuchs wurde durch die Untersuchung der Pulverqualität, der Prozessparameter, der Gefügefehler, der Festigkeit und der Ermüdung die Zuverlässigkeit bestimmt, die Nutzer von AlSi10Mg-Proben erwarten können, die mit pulverbettbasiertes Schmelzen mittels Laser (engl. Laser Powder Bed Fusion) gefertigt worden sind. Abgesehen von einem Ausreißer wurden die erwarteten statischen Materialeigenschaften erreicht. Eine optische Gefügeprüfung diente dazu, die tatsächliche Porosität und Arten von Porosität zu ermitteln, um die bei den Eigenschaften auftretende Streuung zu erklären. Fraktographische Unterschungen zeigen eine bei allen Proben von der rauen Oberfläche im As-built-Zustand ausgehende Ermüdungsrissausbreitung. Aus der statistischen Analyse der Streuung bezüglich der Ermüdung unter Anwendung von statistischen abgeleiteten Sicherheitsfaktoren geht hervor, dass alle Proben die Dauerfestigkeit von 107 Zyklen bei einer Spannung von 36,87 MPa mit einer Überlebenswahrscheinlichkeit von 99,999 % erreichten. KW - Additive manufacturing KW - Reproducibility KW - Reliability PY - 2022 DO - https://doi.org/10.1515/pm-2022-1018 SN - 2195-8599 VL - 59 IS - 10 SP - 580 EP - 614 PB - De Gruyter AN - OPUS4-55935 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zweigle, J. A1 - Schmidt, A. A1 - Bugsel, B. A1 - Vogel, Christian A1 - Simon, Fabian A1 - Zwiener, C. T1 - Perfluoroalkyl acid precursor or weakly fluorinated organic compound? A proof of concept for oxidative fractionation of PFAS and organofluorines N2 - Organofluorine mass balance approaches are increasingly applied to investigate the occurrence of per- and polyfluoroalkyl substances (PFAS) and other organofluorines in environmental samples more comprehensively. Usually, complex samples prevent the identification and quantification of every fluorine-containing molecule. Consequently, large unidentified fractions between fluorine sum parameters such as extractable organic fluorine (EOF) and the sum of quantified analytes are frequently reported. We propose using oxidative conversion to separate (unidentified) weakly fluorinated compounds (e.g., pesticides, pharmaceuticals) from PFAA-precursors (perfluoroalkyl chain lengths ≥ C6). We show with three organofluorine model substances (flufenamic acid, diflufenican, pantoprazole) that CF3-groups or aromatic fluorine can be quantitatively converted to inorganic fluoride and trifluoroacetic acid (TFA) by applying PhotoTOP oxidation (UV/TiO2). The principle of fluorine separation in mixtures is demonstrated by the oxidation of the three weakly fluorinated compounds together with the PFAA-precursor 6:2/6:2 fluorotelomer mercaptoalkyl phosphate diester (FTMAP). After oxidation, the products F− and TFA were separated from PFCAs ( C4) by SPE, and the fractions were analyzed individually. Closed mass balances both with and without the addition of organic matrix were achieved. Eventually, the fluorine balance was verified by total fluorine measurements with combustion ion chromatography (CIC). The proposed methods should be considered a proof of concept to potentially explain unidentified fractions of the EOF, especially if compounds with low fluorine content such as pesticides, pharmaceuticals, and their transformation products contribute largely to the EOF. Future studies are needed to show the applicability to the complexity of environmental samples. Graphical Abstract KW - Combustion Ion Chromatography KW - Per- and Polyfluoroalkyl substances (PFAS) PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613429 DO - https://doi.org/10.1007/s00216-024-05590-5 SP - 1 EP - 10 PB - Springer Science and Business Media LLC AN - OPUS4-61342 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rohn, H. A1 - Simon, Franz-Georg A1 - Schmidt, M. A1 - Giegrich, J. A1 - Oberender, C. A1 - Denz, W. A1 - Niebaum, A. ED - Ludwig, C. ED - Matasci, C. T1 - The Guideline Series VDI 4800 Resource Efficiency: An Approach for Increasing Resource Efficiency with Aim of Conservation of Natural Resources in the Industrial Sector N2 - In 2011, the Association of German Engineers (VDI) started working on a set of guidelines towards increased resource efficiency. These guidelines represent a framework that defines resource efficiency and outlines considerations for the producing industry. A special guideline for SMEs is included as well as guidelines on methodologies for evaluating resource use indicators, such as the cumulative raw material demand of products and production systems. Resource efficiency, defined here as the relationship between a specific benefit or use and the natural resources that need to be spent or consumed to attain this benefit or use. It can be evaluated by defining a function which expresses the specific benefit and quantifies the resource requirements through a set of indicators (use of raw materials, energy, water, land and ecosystem services including sinks). The results from this also depend on the system boundary parameters and the allocation rules for by-products and waste treatment options. Optimising resource use is possible at all stages of a product’s or production system’s life cycle chain (raw material extraction, production and manufacturing, use and consumption, and the end-of-life stage). VDI guidelines are widely accepted across Germany’s industrial sector and therefore represent an important means of mainstreaming resource efficiency in this target area. As well as providing a methodological framework, the guidelines describe strategies and measures towards increasing resource efficiency, and they enable industrial producers and service providers to identify potential areas of improvement. The full article presents an overview of the methodology and contents of these guidelines and discusses their impact in achieving absolute reductions in the industrial use of natural resources. KW - Resource efficiency KW - Life cycle thinking KW - Products and production systems KW - Standardization PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-426443 UR - https://www.wrforum.org/wrfpublicationspdf/boosting-resource-productivity/ SN - 978-3-9521409-7-0 SP - 125 EP - 132 PB - Paul Scherrer Institute CY - Villigen PSI, Switzerland ET - 1 AN - OPUS4-42644 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Veh, Georg A1 - Wang, Björn G. A1 - Zirzow, Anika A1 - Schmidt, Christoph A1 - Lützow, Natalie A1 - Steppat, Frederic A1 - Zhang, Guoqing A1 - Vogel, Kristin A1 - Geertsema, Marten A1 - Clague, John J. A1 - Korup, Oliver T1 - Progressively smaller glacier lake outburst floods despite worldwide growth in lake area N2 - Glacier lake outburst floods (GLOFs) may originate from larger lakes as these continue to grow with ongoing glacier retreat; however, this perception remains poorly supported in available GLOF databases. Here we mapped the areas of 1,686 glacier lakes, just before they drained, across 13 glaciated mountain regions outside polar regions and examined the trends in pre-GLOF lake areas between 1990 and 2023. We found that pre-GLOF lake areas barely changed, or even decreased, regionally through time, even as the total lake area, and thus hazard potential, grew overall. This counterintuitive finding reflects limits to growing GLOF magnitudes, such as the decoupling of lakes and parent glaciers, the development of wide, low-gradient outlets or human management. Across all regions, pre-GLOF lake areas depend on a few ice-dammed lakes, which have produced ten times more reported outbursts and ten times larger outbursts than moraineand bedrock-dammed lakes. The latter two dam types will continue to impound growing amounts of meltwater, thereby accounting for most of the overall GLOF hazard potential, while ice-dammed lakes will shrink with deglaciation. As these lake types will evolve differently in the twenty-first century, we call for customized simulations of GLOF outflows and impacts, given the growing exposure of critical infrastructure. KW - Climate change KW - Bayesian hierachical modelling KW - Outbursts flood PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625709 DO - https://doi.org/10.1038/s44221-025-00388-w SN - 2731-6084 SP - 1 EP - 25 AN - OPUS4-62570 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Everard, C.D. A1 - Schmidt, Martin A1 - McDonnell, K.P. A1 - Finnan, J. T1 - Heating processes during storage of Miscanthus chip piles and numerical simulations to predict self-ignition N2 - Miscanthus x Giganteus (Miscanthus) energy crop was examined at laboratory scale to assess its self-heating and self-ignition risks during storage. Chipped Miscanthus (18 mm) from February and March harvests, in 2012, were assessed as well as ground Miscanthus (3 mm) from the March harvest. February and March crops had moisture contents of 41.6 and 20.2%, respectively. Self-ignition temperatures were independent of moisture although moisture did affect the time from the beginning of storage until storage temperature was reached. Ground Miscanthus had lower self-ignition temperatures than chipped Miscanthus. Isothermal respirometric tests carried out showed increase risk of self-heating in the February crop compared to the March crop due to increased microbial activity. Numerical simulations were used to determine critical enhanced start temperatures, e.g. caused by microbial decomposition, of the stored Miscanthus. Safe storage conditions have been derived from the investigations. The numerical simulations demonstrated that self-ignition was possible in Miscanthus chip piles with a height greater than 6 m if there was significant heat release from microbiological activity. Reliable assessment of self-heating and self-ignition risks in large scale Miscanthus energy crop clamps or piles are required to prevent losses due to decomposition and fire damage. KW - Miscanthus x Giganteus KW - Hot storage test KW - Respirometric rates KW - Self-heating KW - Self-ignition KW - Numerical simulations KW - Biomass storage PY - 2014 DO - https://doi.org/10.1016/j.jlp.2014.06.003 SN - 0950-4230 SN - 1873-3352 VL - 30 SP - 188 EP - 196 PB - Butterworth CY - Guildford, Surrey AN - OPUS4-31149 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Martin A1 - Wu, D. A1 - Norman, F. A1 - Vanierschot, M. A1 - Verplaetsen, F. A1 - Berghmans, J. A1 - van den Bulck, E. T1 - Numerical investigation on the self-ignition behaviour of coal dust accumulations: The roles of oxygen, diluent gas and dust volume N2 - Self-ignition of coal dust deposits poses a higher risk of fires in oxygen-enriched oxy-fuel combustion systems. In this work, we develop a numerical method, using the commercial software COMSOL Multiphysics, to investigate self-ignition behaviour of coal dust accumulations with a main emphasis on the roles of oxygen, diluent gas and dust volume. A one-step 2nd-order reaction kinetic model considering both coal density and oxygen density is used to estimate reaction rate using the kinetic parameters from previously conducted hot-oven tests. This model is validated to predict the transient temperature and concentration profiles of South African coal dusts until ignition. The computed self-ignition temperatures of dust volumes show a good agreement with experimental results. In addition, it is found that the inhibiting effect of carbon dioxide is comparatively small and oxygen consumption increases dramatically after ignition. Parameter analysis shows that the heating value and kinetic parameters have a comparatively pronounced effect on self-ignition temperature. The model provides a satisfactory explanation for the dependence of self-ignition behaviour on gas atmospheres, thus helping to further understand the fire risk of self-ignition in oxy-fuel combustion systems. KW - Ignition temperature KW - Oxy-fuel combustion KW - Fire safety KW - Self-ignition KW - Numerical simulation PY - 2017 DO - https://doi.org/10.1016/j.fuel.2016.10.063 SN - 0016-2361 SP - 500 EP - 510 AN - OPUS4-37885 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kus, J. A1 - Kaufhold, S. A1 - Klosa, D. A1 - Jianwei, M. A1 - Schmidt, Martin A1 - Suhendra, Suhendra T1 - Coal fire geothermometer: Controlling the extent and temperature field of underground coal fire zones T2 - 2nd International conference on coal fire research (ICCFR2) CY - Berlin, Germany DA - 2010-05-19 KW - Coal fires KW - Coal petrography KW - Coal mineralogy PY - 2010 SN - 978-3-86012-397-3 IS - Part 2 - Geosciences SP - 75 EP - 85 AN - OPUS4-21459 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Fischer, C. A1 - Wu, J. A1 - Meyer, U. A1 - Kong, B. A1 - Schmidt, Martin A1 - Wuttke, M. A1 - Drebenstedt, C. A1 - Barth, Uli A1 - Rüter, H. T1 - Eight years of successful bilateral cooperation: Milestones of sino-german research T2 - 2nd International conference on coal fire research (ICCFR2) CY - Berlin, Germany DA - 2010-05-19 KW - Underground coal fires KW - Sino-german cooperation PY - 2010 SN - 978-3-86012-397-3 IS - Introduction SP - 3 EP - 18 AN - OPUS4-21460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baytekin, H. Tarik A1 - Wirth, Thomas A1 - Gross, Thomas A1 - Sahre, Mario A1 - Unger, Wolfgang A1 - Theisen, J. A1 - Schmidt, M. T1 - Surface analytical characterization of micro-fluidic devices hot embossed in polymer wafers: Surface chemistry and wettability N2 - Recently, time-of-flight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) instrumentation has been used to address areas of interest within micro-fluidic devices providing full access to the surface chemistry established at the bottom of micro-channels therein. After careful calibration, information on surface chemistry as obtained by ToF-SIMS or XPS can be interpreted in terms of wettability expressed as contact angles which are then characteristic for the inner walls of micro-channels. Standard contact angle measurement is not applicable in micro-channels. The approach has been demonstrated to be successful with two different micro-fluidic devices hot embossed into high-end quality poly(methyl methacrylate) (PMMA) or Polycarbonate wafers. A pre-selected surface chemistry at micro-channel walls can be established by plasma technologies but ageing and rinsing effects have to be under control. A combination of ToF-SIMS, XPS and contact angle measurement techniques has been demonstrated to provide the required information. Finally, it is shown by ToF-SIMS and XPS analysis that in the production of micro-fluidic parts during practical processing using hot embossing technologies, material originating from cover foils will reside on the polymer wafer's surface. Moreover, residues of releasing agents as silicone oil used during processing can be detected by ToF-SIMS. Both cover foil residues and silicones are issues of trouble shooting in micro-fluidics because they will change contact angles efficiently. KW - Micro-fluidic device KW - PMMA KW - Polycarbonate KW - Plasma treatment KW - Wettability KW - ToF-SIMS KW - XPS PY - 2010 DO - https://doi.org/10.1002/sia.3149 SN - 0142-2421 SN - 1096-9918 VL - 42 IS - 8 SP - 1417 EP - 1431 PB - Wiley CY - Chichester AN - OPUS4-21712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thomsen-Schmidt, P. A1 - Hasche, K. A1 - Ulm, G. A1 - Herrmann, K. A1 - Krumrey, M. A1 - Ade, G. A1 - Stümpel, J. A1 - Busch, I. A1 - Schädlich, S. A1 - Schindler, A. A1 - Frank, W. A1 - Hirsch, D. A1 - Procop, Mathias A1 - Beck, Uwe T1 - Realisation and metrological characterisation of thickness standards below 100 nm N2 - High-accuracy film thickness measurements in the range below 100 nm can be made by various complex methods like spectral ellipsometry (SE), scanning force microscopy (SFM), grazing incidence X-ray reflectometry (GIXR), or X-ray fluorescence analysis (XRF). The measurement results achieved with these methods are based on different interactions between the film and the probe. A key question in nanotechnology is how to achieve consistent results on a level of uncertainty below one nanometre with different techniques. Two different types of thickness standards are realised. Metal film standards for X-ray techniques in the thickness range 10 to 50 nm are calibrated by GIXR with monochromatised synchrotron radiation of 8048 eV. The results obtained at four different facilities show excellent agreement. SiO2 on Si standards for SE and SFM in the thickness range 6 to 1000 nm are calibrated by GIXR with monochromatised synchrotron radiation of 1841 eV and with a metrological SFM. Consistent results within the combined uncertainties are obtained with the two methods. Surfaces and interfaces of both types of standards are additionally investigated by transmission electron microscopy (TEM). PY - 2004 DO - https://doi.org/10.1007/s00339-003-2273-7 SN - 0947-8396 VL - 78 IS - 5 SP - 645 EP - 649 PB - Springer CY - Berlin AN - OPUS4-17195 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baytekin, H.T. A1 - Wirth, Thomas A1 - Gross, Thomas A1 - Treu, Dieter A1 - Sahre, Mario A1 - Theisen, J. A1 - Schmidt, M. A1 - Unger, Wolfgang T1 - Determination of wettability of surface-modified hot-embossed polycarbonate wafers used in microfluidic device fabrication via XPS and ToF-SIMS N2 - The wettability of the surfaces inside the microchannels of a microfluidic device is an important property considering a liquid flows through them. Contact angle measurements usually applied to test the wettability of surfaces cannot be used for an analysis of microchannel walls within microfluidic devices. A workaround is the use of surface analytical methods, which are able to reach points of interest in microchannels and may provide information on the surface chemistry established there. In calibrating these methods by using flat polymer wafers, where the contact angle can be measured as usual, data measured in real microchannels can be evaluated in terms of wetting properties. Reference wafers of bisphenol-A polycarbonate, a polymeric material that is often used in fluidic microdevice fabrication, were treated under different oxygen plasma conditions. The modified surfaces were characterized by using XPS, time of flight (ToF)-SIMS and atomic force microscope (AFM). Surface chemistry and surface topography have been correlated with contact angle measurements. In addition, effects of ageing or rinsing after plasma treatment have also been investigated. KW - Oxygen plasma KW - Polycarbonate KW - XPS KW - ToF-SIMS KW - Principal component analysis PY - 2008 DO - https://doi.org/10.1002/sia.2724 SN - 0142-2421 SN - 1096-9918 VL - 40 IS - 3-4 SP - 358 EP - 363 PB - Wiley CY - Chichester AN - OPUS4-17340 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schoßig, Jörg A1 - Schmidt, Martin A1 - Krause, Ulrich A1 - Steinbach, J. T1 - Beurteilung des Selbstentzündungsverhaltens brennbarer Stäube mit Hilfe adiabatischer Warmlagerung T2 - 10. Fachtagung Anlagen-, Arbeits- und Umweltsicherheit CY - Köthen, Deutschland DA - 2010-11-04 KW - Anlagensicherheit KW - Umweltschutz KW - Sicherheitstechnik KW - Explosionsschutz PY - 2010 SN - 978-3-89746-119-2 SP - 1 EP - 7(?) CY - Frankfurt/M. AN - OPUS4-22621 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schoßig, Jörg A1 - Schmidt, Martin A1 - Krause, Ulrich A1 - Steinbach, J. T1 - Validierung von formalkinetischen Größen aus der adiabaten Warmlagerung T2 - 9. Fachtagung "Anlagen-, Arbeits- und Umweltsicherheit" CY - Köthen, Deutschland DA - 2008-11-06 KW - Anlagensicherheit KW - Umweltschutz KW - Sicherheitstechnik KW - Explosionsschutz PY - 2008 SN - 978-3-89746-099-7 SP - 1 EP - 3 PB - VDI, Hallescher Bezirksverein CY - Halle AN - OPUS4-18427 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dreßler, Martin A1 - Röllig, Mathias A1 - Schmidt, Martin A1 - Maturilli, A. A1 - Helbert, J. T1 - Temperature distribution in powder beds during 3D printing N2 - Purpose – This purpose of this paper is to report about the temperature distribution in metal and ceramic powder beds during 3D printing. The differing powders are thoroughly characterized in terms of thermal conductivity, thermal diffusivity, emissivity spectra and density. Design/methodology/approach – The temperature distribution was measured in a 3D printing appliance (Prometal R1) with the help of thin thermocouples (0.25 mm diameter) and thermographic imaging. Temperatures at the powder bed surface as well as at differing powder bed depths were determined. The thermal conductivity, thermal diffusivity and emissivity spectra of the powders were measured as well. Numerical simulation was used to verify the measured temperatures. Findings – The ceramic powder heated up and cooled down more quickly. This finding corresponds well with numerical simulations based on measured values for thermal conductivity and thermal diffusivity as well as emissivity spectra. An observed color change at the metal powder has only little effect on emissivity in the relevant wavelength region. Research limitations/implications – It was found that thermocouple-based temperature measurements at the powder bed surface are difficult and these results should be considered with caution. Practical implications – The results give practitioners valuable information about the transient temperature evolution for two widely used but differing powder systems (metal, ceramic). The paramount importance of powder bed porosity for thermal conductivity was verified. Already small differences in thermal conductivity, thermal diffusivity and hence volumetric heat capacity lead to marked differences in the transient temperature evolution. Originality/value – The paper combines several techniques such as temperature measurements, spectral emissivity measurements, measurements of thermal conductivity and diffusivity and density measurements. The obtained results are put into a numerical model to check the obtained temperature data and the other measured values for consistency. This approach illustrates that determinations of surface temperatures of the powder beds are difficult. KW - Rapid prototypes KW - Printers KW - Heat transfer KW - Powders KW - Ceramics KW - Metals PY - 2010 DO - https://doi.org/10.1108/13552541011065722 SN - 1355-2546 VL - 16 IS - 5 SP - 328 EP - 336 PB - MCB University Press CY - Bradford AN - OPUS4-22002 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lohrer, Christian A1 - Schmidt, Martin A1 - Malow, Marcus A1 - Krause, Ulrich A1 - Steinbach, J. T1 - Einfluss von Feuchte und Konvektionsströmung auf das Selbstentzündungsverhalten von Feststoffschüttungen KW - Selbstentzündung KW - Konvektion KW - Feuchte PY - 2005 DO - https://doi.org/10.1002/cite.200590078 SN - 0009-286X SN - 1522-2640 VL - 77 IS - 8 SP - 1141 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-10847 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hasche, K. A1 - Ulm, G. A1 - Herrmann, K. A1 - Krumrey, M. A1 - Ade, G. A1 - Sümpel, J. A1 - Busch, I. A1 - Thomsen-Schmidt, P. A1 - Schädlich, S. A1 - Schindler, A. A1 - Frank, W. A1 - Procop, Mathias A1 - Beck, Uwe T1 - About the calibration of thickness standards on the nanometer scale T2 - 3rd International EUSPEN conference ; 3rd International conference. European Society for Precision Engineering and Nanotechnology ; 4th General meeting. European Society for Precision Engineering and Nanotechnology CY - Eindhoven, The Netherlands DA - 2002-05-26 PY - 2002 SN - 90-386-2883-8 SP - 1 EP - 5 CY - Eindhoven AN - OPUS4-2283 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hasche, K. A1 - Herrmann, K. A1 - Thomsen-Schmidt, P. A1 - Krumrey, M. A1 - Ulm, G. A1 - Ade, G. A1 - Pohlenz, F. A1 - Stümpel, J. A1 - Busch, I. A1 - Schädlich, S. A1 - Frank, W. A1 - Hirsch, D. A1 - Schindler, A. A1 - Procop, Mathias A1 - Beck, Uwe T1 - Ein Beitrag zu kalibrierten Nanometerschichten für unterschiedliche Anwendungsbereiche N2 - Nanotechnologien werden gegenwärtig als leistungsfähige Oberflächentechniken in erheblichem Umfange industriell genutzt. Dabei spielen dünne Schichten und deren Kenndaten eine wesentliche Rolle, z.B. als Röntgenspiegel oder optische und magnetooptische Datenträger. Die Schichtdicke zählt hierbei zu den technologisch wichtigen Parametern. Abgeleitet von Anwenderinteressen, werden für die Röntgenreflektometrie (XRR bzw. GIXR), Elektronenstrahl-Mikroanalyse (EPMA) und Röntgenfluoreszenzanalyse (XRF) einerseits und die Ellipsometrie andererseits zugeschnittene Schichtdickenmaßverkörperungen (SDM) entwickelt, gefertigt und untersucht. Das Ziel ist die Bereitstellung praxistauglicher, kalibrierter SDM, im weiteren Schichtdickennormale (SDN) genannt. SDN sind Maßverkörperungen, für die der Schichtdickenwert mit einer definierten Messunsicherheit bekannt und auf ein metrologisch anerkanntes Längennormal zurückgeführt ist. Berichtet wird über die Herstellung und messtechnische Charakterisierung der beiden spezifischen Varianten von Maßverkörperungen. T2 - 47. Internationales Wissenschaftliches Kolloquium. Technische Universität Ilmenau ; Herbstkonferenz der Gesellschaft für Arbeitswissenschaft ; 6. Workshop Multimedia für Bildung und Wirtschaft CY - Ilmenau, Deutschland DA - 2002-09-23 PY - 2002 UR - http://publica.fraunhofer.de/documents/N-14872.html VL - 47 SP - 568 EP - 569 PB - Techn. Univ. CY - Ilmenau AN - OPUS4-2284 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koenders, L. A1 - Hasche, K. A1 - Ulm, G. A1 - Krumrey, M. A1 - Ade, G. A1 - Stümpel, J. A1 - Busch, I. A1 - Thomsen-Schmidt, P. A1 - Schädlich, S. A1 - Schindler, A. A1 - Frank, W. A1 - Beck, Uwe A1 - Procop, Mathias T1 - Über die metrologische Charakterisierung von Schichtdicken Standards im Nanometerbereich T2 - 12th Applied Surface Analysis Workshop ; AOFA 12 CY - --- DA - 2002-09-15 PY - 2002 AN - OPUS4-2285 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völzke, Holger A1 - Schmidt, A. J. T1 - Koordinierungsstelle für Informationen zur Behälterabfertigung (KOBAF / BIBO) T2 - 3. Symposium "Beförderung und Lagerung radioaktiver Stoffe - Stand der BE-Entsorgung" CY - Hannover, Deutschland DA - 2003-05-08 PY - 2003 AN - OPUS4-2500 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -