TY - CONF A1 - Simon, Fabian T1 - A fast and simple extraction method for the determination of PFASs in soil samples - HR-CS-GFMAS a new screening tool N2 - Here, we describe a fast and simple extraction method for the determination of per- and polyfluorinated alkyl substances (PFASs) utilizing extractable organic fluorine (EOF) sum parameter analysis and high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) in soil samples. After extraction and separation of inorganic and organic fluorinated compounds, organically bound fluorinated compounds were indirectly determined via the molecular absorption of gallium mono-fluoride at 211.248 nm. The implementation of the decisions of the “Stockholm Convention on persistent organic pollutants” as well as the “Protocol on Persistent Organic Pollutants of the Convention on Long-Range Transboundary Air Pollution” of the UNECE include the reduction respectively the elimination of PFASs in the environment. Currently, regulations aim to target single compounds (mostly C8-PFAS). But the PFAS group includes over 4700 substances, which are potentially persistent and toxic, thus target analytical approaches are not suitable for a holistic approach investigating the PFAS pollutant situation. Furthermore, forbidden PFASs are substituted by short-chain PFASs, thus the number of unknow substances is steadily increasing. For this reason, sum parameter approaches are more suitable to investigate and assess the pollution situation as well as derive exposure limits. Our developed analytical method was successfully applied to determine PFASs in soil samples from a polluted site. In view of steadily increasing numbers of PFAS substances, our method will make an important contribution in assessing the pollution situation as well as support policy makers in deriving exposure limits for PFAS in the future. T2 - ENSOr - International Workshop on Emerging policy challenges on new soil contaminants CY - Online Meeting DA - 06.05.2021 KW - PFAS KW - HR-CS-GFMAS KW - Soil KW - Sediment PY - 2021 AN - OPUS4-52608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brauckmann, C. A1 - Pramann, A. A1 - Rienitz, O. A1 - Schulze, A. A1 - Phukphatthanachai, Pranee A1 - Vogl, Jochen T1 - Combining Isotope Dilution and Standard Addition—Elemental Analysis in Complex Samples N2 - A new method combining isotope dilution mass spectrometry (IDMS) and standard addition has been developed to determine the mass fractions w of different elements in complex matrices: (a) silicon in aqueous tetramethylammonium hydroxide (TMAH), (b) sulfur in biodiesel fuel, and (c) iron bound to transferrin in human serum. All measurements were carried out using inductively coupled plasma mass spectrometry (ICP–MS). The method requires the gravimetric preparation of several blends (bi)—each consisting of roughly the same masses (mx,i) of the sample solution (x) and my,i of a spike solution (y) plus different masses (mz,i) of a reference solution (z). Only these masses and the isotope ratios (Rb,i) in the blends and reference and spike solutions have to be measured. The derivation of the underlying equations based on linear regression is presented and compared to a related concept reported by Pagliano and Meija. The uncertainties achievable, e.g., in the case of the Si blank in extremely pure TMAH of urel (w(Si)) = 90% (linear regression method, this work) and urel (w(Si)) = 150% (the method reported by Pagliano and Meija) seem to suggest better applicability of the new method in practical use due to the higher robustness of regression analysis. KW - Isotope dilution mass spectrometry KW - tandard addition KW - ICP-MS KW - lank characterization KW - Silicon KW - Sulfur KW - Transferrin KW - Tetramethylammonium hydroxide KW - Biodiesel fuel KW - Human serum PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526376 DO - https://doi.org/10.3390/molecules26092649 VL - 26 IS - 9 SP - 2649 PB - MDPI CY - Basel AN - OPUS4-52637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Held, Mathias T1 - Inverse determination of elastic material parameters from ultrasonic guided waves dispersion measurements using Convolutional Neuronal Networks N2 - This presentation shows how the dispersive behavior of ultrasonic guided waves in isotropic materials can be used by means of Convolutional Neural Networks to determine the elastic parameters. For this purpose, the preprocessing, the training, the chosen architecture and the results are evaluated on the basis synthetic image data. This presentation was given at the SMSI 2021. T2 - SMSI 2021 2021-05-03 - 2021-05-06 digital CY - Online Meeting DA - 03.05.2021 KW - Guided waves KW - Inverse Probleme KW - Materialcharakterisierung KW - Convolutional Neuronal Networks KW - Dispersion PY - 2021 AN - OPUS4-52625 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zeipert, H. A1 - Claes, L. A1 - Johannesmann, S. A1 - Webersen, M. A1 - Lugovtsova, Yevgeniya A1 - Prager, Jens A1 - Henning, B. T1 - Measurement and simulation of Lamb waves in adhesive-bonded multilayer systems N2 - Lamb waves are a common tool in the field of non-destructive testing and are widely used for materialcharacterisation. Further, the increasing computational capability of modern systems enables the Simulation of complex and detailed material models. This work demonstrates the possibility of simulating an adhesive-bonded multilayer system by characterising each layer individually, and introduces an Approach for determining the dispersive behaviour of acoustic waves in a multilayer system via real measurements. T2 - SMSI 2021 Conference – Sensor and Measurement Science International CY - Online meeting DA - 03.05.2021 KW - Adhesive bonds KW - Lamb waves KW - Elastic constants KW - Non-Destructive Testing KW - Ultrasound PY - 2021 DO - https://doi.org/10.5162/SMSI2021/A8.2 SP - 91 EP - 92 AN - OPUS4-52634 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zeipert, H. T1 - Measurement and simulation of Lamb waves in adhesive-bonded multilayer systems N2 - Lamb waves are a common tool in the field of non-destructive testing and are widely used for material characterisation. Further, the increasing computational capability of modern systems enables the Simulation of complex and detailed material models. This work demonstrates the possibility of simulating an adhesive-bonded multilayer system by characterising each layer individually, and introduces an Approach for determining the dispersive behaviour of acoustic waves in a multilayer system via real measurements. T2 - SMSI 2021 Conference – Sensor and Measurement Science International CY - Online meeting DA - 03.05.2021 KW - Adhesive bonds KW - Lamb waves KW - Elastic constants KW - Non-Destructive Testing KW - Ultrasound PY - 2021 AN - OPUS4-52635 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meermann, Björn T1 - Elemental analytical methods in material- & environmental analysis N2 - Materials in contact with the environment release e.g., metal-ions, elemental species and/or (nano-)particles. Once these species and/or particles are released, they are ingested by organisms and cells and thus, might have a negative impact on the environment. Thus, identification as well as quantification of potentially harmful substances is of utmost importance and highly needed to assess ecotoxicological impact of (emerging) pollutants. The oral presentation provides an overview on the power of elemental analytical techniques, in particular: ICP-MS as well as HR-CS-GFMAS in environmental research. Current research topics will be highlighted: i) Elemental Speciation analysis of anti-fouling agents via CE/MC-ICP-MS; ii) Per- and polyfluorinated compounds in surface waters via high resolution-continuum source-graphite furnace molecular absorption spectroscopy (HR-CS-GFMAS); iii) Single cell and single organism analysis via sc-ICP-ToF-MS and ETV/ICP-MS for ecotoxicological assessment. T2 - Analytical Colloquium at MERCK CY - Online meeting DA - 19.04.2021 KW - HR-CS-GFMAS KW - ICP-ToF-MS KW - ETV/ICP-MS PY - 2021 AN - OPUS4-52566 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiesner, Yosri A1 - Altmann, Korinna A1 - Braun, U. T1 - Determination of Microplastic Mass Content by Thermal Extraction Desorption Gas Chromatography– Mass Spectrometry N2 - The scientific and practical challenge of detecting microplastics (MPs) in the environment in a targeted and rapid manner is solved by innovative coupling of thermogravimetric analysis with mass spectrometric methods. Fast identification and quantitative determination of most thermoplastic polymers and elastomers is possible by using thermal extraction Desorption gas chromatography–mass spectrometry (TED-GC–MS). KW - Microplastics KW - Mikroplastik KW - TED-GC/MS KW - Microplastics analytic KW - Mikroplastik Massegehalt PY - 2021 VL - 17 IS - 3 SP - 2 EP - 7 PB - MultiMedia (UK) LLC CY - Cranbury AN - OPUS4-52570 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shipov, A. A1 - Zaslansky, P. A1 - Riesemeier, Heinrich A1 - Segev, G. A1 - Atkins, A. A1 - Kalish-Achrai, N. A1 - Weiner, S. A1 - Shahar, R. T1 - The influence of estrogen deficiency on the structural and mechanical properties of rat cortical bone N2 - Background. Post-menopausal osteoporosis is a common health problem worldwide, most commonly caused by estrogen deficiency. Most of the information regarding the skeletal effects of this disease relates to trabecular bone, while cortical bone is less studied. The purpose of this study was to evaluate the influence of estrogen deficiency on the structure and mechanical properties of cortical bone. Methods. Eight ovariectomized (OVH) and eight intact (control) Sprague Dawley rats were used. Structural features of femoral cortical bone were studied by light microscopy, scanning electron microscopy and synchrotron-based microcomputer-tomography and their mechanical properties determined by nano-indentation. Results. Cortical bone of both study groups contains two distinct regions: organized circumferential lamellae and disordered bone with highly mineralized cartilaginous islands. Lacunar volume was lower in the OVH group both in the lamellar and disorganized regions (182 ± 75 µm3 vs 232 ± 106 µm3 , P < 0.001 and 195 ± 86 µm3 vs. 247 ± 106 µm3 , P < 0.001, respectively). Lacunar density was also lower in both bone regions of the OVH group (40 ± 18 ×103 lacunae/mm3 vs. 47 ± 9×103 lacunae/mm3 in the lamellar region, P = 0.003 and 63 ± 18×103 lacunae/mm3 vs. 75 ± 13×103 lacunae/mm3 in the disorganized region, P < 0.001). Vascular canal volume was lower in the disorganized region of the bone in the OVH group compared to the same Region in the control group (P < 0.001). Indentation moduli were not different between the study groups in both bone regions. Discussion. Changes to cortical bone associated with estrogen deficiency in rats require high-resolution methods for detection. Caution is required in the application of These results to humans due to major structural differences between human and rat bone. KW - Estrogen KW - Disorganized bone KW - Rat KW - Lacunae KW - Ovariectomy PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520798 DO - https://doi.org/10.7717/peerj.10213 VL - 9 SP - e10213 AN - OPUS4-52079 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lai, W. W.L. A1 - Chang, R.K.W. A1 - Völker, Christoph A1 - Cheung, B. W.Y. T1 - GPR wave dispersion for material characterization N2 - This paper studies the dispersion of GPR wave’s phase velocity at different wideband frequencies in plywood and concrete with varying moisture content. This study makes use of two GPR antennas with 2 GHz centre frequency operating in wide angle reflection and refraction (WARR) mode and with computation of spectral analysis of the surface wave (SASW). Computation of phase velocities is based on the Acquisition of the cross-power spectrum and phase unwrap of two distorted ground waves at positions Closer to and farther away from the transmitting antenna. The velocities of the ground waves are found to experience greater dispersion in low frequency regimes within the effective frequency bandwidths determined and thresholded by time–frequency analysis (TFA) and coherence plotting of the ground waves. This study validates not only the methodology, but also identifies the optimal distance between the first (Rx1) and second (Rx2) receivers as k/2, which is based on a fixed transmitter (Tx) minus the first Receiver (Rx1) distance. It serves as an indication of changeable separation distance when other lower frequency GPR is used because the distances of Tx-Rx1 and Rx1-Rx2 are wavelength dependent and thus also frequency dependent. Effects of moisture contents and chloride contamination in concrete were also characterized according to the dispersion plots . that wave traelling in lower frequencies in GPR wave is much decelerated than that in higher frequencies. This research also contributes to the building of the ‘‘GPRWARR machine” suggested in Annan and Jackson (2017) [1], within which the effects of wave Dispersion on phase velocity can be inversely modelled to characterize variations in the material properties of infrastructure as a means of detecting surface damage. KW - Ground penetrating radar KW - Wide angle reflection and refraction PY - 2021 DO - https://doi.org/10.1016/j.conbuildmat.2021.122597 SN - 0950-0618 VL - 282 SP - 122597 PB - Elsevier Ltd. AN - OPUS4-52197 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Anzt, H. A1 - Bach, F. A1 - Druskat, S. A1 - Löffler, F. A1 - Loewe, A. A1 - Renard, B. Y. A1 - Seemann, G. A1 - Struck, A. A1 - Achhammer, E. A1 - Aggarwal, P. A1 - Appel, F. A1 - Bader, M. A1 - Brusch, L. A1 - Busse, C. A1 - Chourdakis, G. A1 - Dabrowski, P. W. A1 - Ebert, P. A1 - Flemisch, B. A1 - Friedl, S. A1 - Fritzsch, B. A1 - Funk, M. D. A1 - Gast, V. A1 - Goth, F. A1 - Grad, J. A1 - Hegewald, J. A1 - Hermann, S. A1 - Hohmann, F. A1 - Janosch, S. A1 - Kutra, D. A1 - Linxweiler, J. A1 - Muth, Thilo A1 - Peters-Kottig, W. A1 - Rack, F. A1 - Raters, F. H. C. A1 - Rave, S. A1 - Reina, G. A1 - Reißig, M. A1 - Ropinski, T. A1 - Schaarschmidt, J. A1 - Seibold, H. A1 - Thiele, J. P. A1 - Uekermann, B. A1 - Unger, S. A1 - Weeber, R. T1 - An environment for sustainable research software in Germany and beyond: current state, open challenges, and call for action N2 - Research software has become a central asset in academic research. It optimizes existing and enables new research methods, implements and embeds research knowledge, and constitutes an essential research product in itself. Research software must be sustainable in order to understand, replicate, reproduce, and build upon existing research or conduct new research effectively. In other words, software must be available, discoverable, usable, and adaptable to new needs, both now and in the future. Research software therefore requires an environment that supports sustainability. Hence, a change is needed in the way research software development and maintenance are currently motivated, incentivized, funded, structurally and infrastructurally supported, and legally treated. Failing to do so will threaten the quality and validity of research. In this paper, we identify challenges for research software sustainability in Germany and beyond, in terms of motivation, selection, research software engineering personnel, funding, infrastructure, and legal aspects. Besides researchers, we specifically address political and academic decision-makers to increase awareness of the importance and needs of sustainable research software practices. In particular, we recommend strategies and measures to create an environment for sustainable research software, with the ultimate goal to ensure that software-driven research is valid, reproducible and sustainable, and that software is recognized as a first class citizen in research. This paper is the outcome of two workshops run in Germany in 2019, at deRSE19 - the first International Conference of Research Software Engineers in Germany - and a dedicated DFG-supported follow-up workshop in Berlin. KW - Research Software KW - Sustainable Software Development KW - Academic Software KW - Software Infrastructure KW - Software Training KW - Software Licensing PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522029 DO - https://doi.org/10.12688/f1000research.23224.2 VL - 9 SP - 1 EP - 35 AN - OPUS4-52202 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pech, S. A1 - Rehberg, M. A1 - Janke, R. A1 - Benndorf, D. A1 - Genzel, Y. A1 - Muth, Thilo A1 - Sickmann, A. A1 - Rapp, E. A1 - Reichl, U. T1 - Tracking changes in adaptation to suspension growth for MDCK cells: cell growth correlates with levels of metabolites, enzymes and proteins N2 - Adaptations of animal cells to growth in suspension culture concern in particular viral vaccine production, where very specific aspects of virus-host cell interaction need to be taken into account to achieve high cell specific yields and overall process productivity. So far, the complexity of alterations on the metabolism, enzyme, and proteome level required for adaptation is only poorly understood. In this study, for the first time, we combined several complex analytical approaches with the aim to track cellular changes on different levels and to unravel interconnections and correlations. Therefore, a Madin-Darby canine kidney (MDCK) suspension cell line, adapted earlier to growth in suspension, was cultivated in a 1-L bioreactor. Cell concentrations and cell volumes, extracellular metabolite concentrations, and intracellular enzyme activities were determined. The experimental data set was used as the input for a segregated growth model that was already applied to describe the growth dynamics of the parental adherent cell line. In addition, the cellular proteome was analyzed by liquid chromatography coupled to tandem mass spectrometry using a label-free protein quantification method to unravel altered cellular processes for the suspension and the adherent cell line. Four regulatory mechanisms were identified as a response of the adaptation of adherent MDCK cells to growth in suspension. These regulatory mechanisms were linked to the proteins caveolin, cadherin-1, and pirin. Combining cell, metabolite, enzyme, and protein measurements with mathematical modeling generated a more holistic view on cellular processes involved in the adaptation of an adherent cell line to suspension growth. KW - MDCK cell KW - Proteome KW - Metabolism KW - Enzyme activity KW - Suspension growth PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522070 DO - https://doi.org/10.1007/s00253-021-11150-z VL - 105 IS - 5 SP - 1861 EP - 1874 PB - Springer AN - OPUS4-52207 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kling e Silva, L. A1 - Almeida, G. A1 - Kadoke, Daniel A1 - Daum, Werner A1 - Ribeiro Pereira, G. T1 - Automation of pipe defect detection and characterization by structured light N2 - High quality tubular products are essential to the oil and gas industry. Quality control during their production focuses on the non-destructive detection of surface defects. The structured light technique is a candidate for the challenge to detect, monitor and evaluate such defects in real-time. In the present study the automatic processing of structured light measurements is performed and validated. The algorithm for the automatic Analysis of inspection data has an advantage over current data evaluation methods based on individual assessments of operators. KW - Non-destructive testing KW - Data processing KW - Defect evaluation KW - Materials evaluation KW - Structured light scanning (SLS) PY - 2021 DO - https://doi.org/10.1515/mt-2020-0008 SN - 0033-8230 VL - 63 IS - 1 SP - 55 EP - 61 PB - Walter de Gruyter GmbH CY - Berlin/ Boston AN - OPUS4-52124 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Frisch, M. A1 - Laun, J. A1 - Marquardt, Julien A1 - Arinchtein, A. A1 - Bauerfeind, K. A1 - Bernsmeier, D. A1 - Bernicke, M. A1 - Bredow, T. A1 - Kraehnert, R. T1 - Bridging experiment and theory: enhancing the electrical conductivities of soft-templated niobium-doped mesoporous titania films† N2 - Theoretical calculations suggest a strong dependence of electrical conductivity and doping concentration in transition-metal doped titania. Herein, we present a combined theoretical and experimental approach for the prediction of relative phase stability and electrical conductivity in niobium-doped titania as model system. Our method paves the way towards the development of materials with improved electrical properties. KW - Electrical conductivity KW - Prediction relative KW - Transition-metal doped KW - System method PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521371 DO - https://doi.org/10.1039/d0cp06544g SN - 1463-9084 VL - 23 IS - 5 SP - 3219 EP - 3224 PB - Royal Society of Chemistry AN - OPUS4-52137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, Z. A1 - Kneipp, Janina T1 - Ligand-Supported Hot Electron Harvesting: Revisiting the pHResponsive Surface-Enhanced Raman Scattering Spectrum of p‑Aminothiophenol N2 - The discussion of the surface-enhanced Raman scattering (SERS) spectra of p-aminothiophenol (PATP) and of ist photocatalytic reaction product 4,4′-dimercaptoazobenzene (DMAB) is important for understanding plasmon-supported spectroscopy and catalysis. Here, SERS spectra indicate that DMAB forms also in a nonphotocatalytic reaction on silver nanoparticles. Spectra measured at low pH, in the presence of the acids HCl, H2SO4, HNO3, and H3PO4, show that DMAB is reduced to PATP when both protons and chloride ions are present. Moreover, the successful reduction of DMAB in the presence of other, halide and nonhalide, ligands suggests a central role of these species in the reduction. As discussed, the ligands increase the efficiency of hot-electron harvesting. The pH-associated reversibility of the SERS spectrum of PATP is established as an Observation of the DMAB dimer at high pH and of PATP as a product of its hot-electron reduction at low pH, in the presence of the appropriate ligand. KW - Redox reactions KW - Metal nanoparticles KW - Ligands KW - Raman spectroscopy KW - Nanoparticle formation PY - 2021 DO - https://doi.org/10.1021/acs.jpclett.0c03732 SN - 1948-7185 VL - 12 IS - 5 SP - 1542 EP - 1547 PB - ACS Publications AN - OPUS4-52140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Essig, W. A1 - Bernhardt, Y. A1 - Döring, D. A1 - Solodov, I. A1 - Gautzsch, T. A1 - Gaal, Mate A1 - Hufschläger, Daniel A1 - Sommerhuber, R. A1 - Marhenke, T. A1 - Hasener, J. A1 - Szewieczek, A. A1 - Hillger, W. T1 - Air-coupled ultrasound - emerging NDT method N2 - This paper deals with the state of the art of air-coupled ultrasonic testing. KW - Air-coupled KW - Ultrasonic testing KW - Transducers PY - 2021 SN - 1616-069X VL - 173 SP - 32 EP - 43 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-52231 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weller, Michael G. T1 - The Protocol Gap N2 - Although peer review is considered one of the main pillars of modern science, experimental methods and protocols seem to be not a rigorous subject of this process in many papers. Commercial equipment, test kits, labeling kits, previously published concepts, and standard protocols are often considered to be not worth a detailed description or validation. Even more disturbing is the extremely biased citation behavior in this context, which sometimes leads to surrogate citations to avoid low-impact journals, preprints, or to indicate traditional practices. This article describes some of these surprising habits and suggests some measures to avoid the most unpleasant effects, which in the long term may undermine the credibility of science as a whole. KW - Validation KW - Peer review KW - Experiment KW - Documentation KW - Scientific publication KW - Reproducibility crisis KW - Replication crisis KW - Trust KW - Citation KW - References KW - Surrogate citations KW - Impact PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521440 DO - https://doi.org/10.3390/mps4010012 SN - 2409-9279 VL - 4 IS - 1 SP - 1 EP - 5 PB - MDPI CY - Basel AN - OPUS4-52144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Paul, Martin A1 - Tannenberg, Robert A1 - Tscheuschner, Georg A1 - Ponader, Marco A1 - Weller, Michael G. T1 - Cocaine detection by a laser-induced immunofluorometric biosensor N2 - The trafficking of illegal drugs by criminal networks at borders, harbors, or airports is an increasing issue in public health as these routes ensure the main supply of illegal drugs. The prevention of drug smuggling, including the installation of scanners and other analytical devices to detect ultra-small traces of drugs within a reasonable time frame, remains a challenge. The presented immunosensor is based on a monolithic affinity column with a large excess of immobilized hapten, which traps fluorescently labeled antibodies as long as the analyte cocaine is absent. In the presence of the drug, some binding sites of the antibody will be blocked, which leads to an immediate breakthrough of the labeled protein, detectable by highly sensitive laser-induced fluorescence with the help of a Peltier-cooled complementary metal-oxide-semiconductor (CMOS) camera. Liquid handling is performed with high-precision syringe pumps and microfluidic chip-based mixing devices and flow cells. The biosensor achieved limits of detection of 23 pM (7 ppt) of cocaine with a response time of 90 seconds and a total assay time below 3 minutes. With surface wipe sampling, the biosensor was able to detect 300 pg of cocaine. This immunosensor belongs to the most sensitive and fastest detectors for cocaine and offers near-continuous analyte measurement. KW - Drug search KW - Customs KW - Confiscation KW - Border surveillance KW - Narcotics KW - International drug trade KW - Drug trafficking KW - Illicit drug KW - Immunosensor KW - Antibodies KW - Detection PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529951 DO - https://doi.org/10.20944/preprints202107.0521.v1 SN - 2310-287X N1 - Geburtsname von Ponader, Marco: Wilke, M. - Birth name of Ponader, Marco: Wilke, M. SP - 1 PB - MDPI CY - Basel AN - OPUS4-52995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Faßbender, Sebastian A1 - von der Au, Marcus A1 - Koenig, Maren A1 - Pelzer, J. A1 - Piechotta, Christian A1 - Vogl, Jochen A1 - Meermann, Björn T1 - Species-specific isotope dilution analysis of monomethylmercury in sediment using GC/ICP-ToF-MS and comparison with ICP-Q-MS and ICP-SF-MS N2 - A recently introduced inductively coupled plasma-time-of-flight-mass spectrometer (ICP-ToF-MS) shows enhanced sensitivity compared to previous developments and superior isotope ratio precision compared to other ToF and commonly used single-collector ICP-MS instruments. Following this fact, an improvement for isotope dilution ICP-MS using the new instrumentation has been reported. This study aimed at investigating whether this improvement also meets the requirements of species-specific isotope dilution using GC/ICP-MS, where short transient signals are recorded. The results of the analysis of monomethylmercury (MMHg) of a sediment reference material show that isotope ratio precision of ICP-MS instruments equipped with quadrupole, sector-field, and time-of-flight mass analyzers is similar within a broad range of peak signal-to-noise ratio when analyzing one isotopic system. The procedural limit of quantification (LOQ) for MMHg, expressed as mass fraction of Hg being present as MMHg, w(Hg)MMHg, was similar as well for all investigated instruments and ranged between 0.003 and 0.016 μg/kg. Due to the simultaneous detection capability, the ICP-ToF-MS might, however, be more favorable when several isotopic systems are analyzed within one measurement. In a case study, the GC/ICP-ToF-MS coupling was applied for analysis of MMHg in sediments of Finow Canal, a historic German canal heavily polluted with mercury. Mass fractions between 0.180 and 41 μg/kg (w(Hg)MMHg) for MMHg, and 0.056 and 126 mg/kg (w(Hg)total) for total mercury were found in sediment samples taken from the canal upstream and downstream of a former chemical plant. KW - Methylmercury KW - Legacy pollution KW - Finow Canal KW - Isotope dilution KW - Mercury speciation PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529967 DO - https://doi.org/10.1007/s00216-021-03497-z SN - 1618-2642 VL - 413 IS - 21 SP - 5279 EP - 5289 PB - Springer CY - Berlin AN - OPUS4-52996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogl, Jochen T1 - The triple isotope calibration approach BT - A new calibration approach for obtaining absolute isotope ratios of multi-isotopic elements N2 - The calibration of isotope ratio measurements is an ongoing challenge since instrumental isotope fractionation (IIF) has been detected in mass spectrometry (MS). There is a variety of approaches which either bypass IIF such as delta measurements or refer to reference materials (RMs) and thus shifting the problem of calibration to somebody else: the RM producer. For certifying isotope RMs with absolute isotope ratios only a few approaches are available, namely the isotope mixture approach, the double spike approach, the mass bias regression model and total evaporation in TIMS. All of them require either enriched isotopes, isotope RMs of another element or an RM for correcting residual error. As the enriched isotopes required for the isotope mixture and the double spike approach need to be fully characterized beforehand, all mentioned calibration approaches require a standard. Here, a new and standard-free calibration approach for obtaining absolute isotope ratios of multi-isotopic elements has been developed. The underlying principle is that each MS suffers from IIF and thus yields a specific isotope fractionation line in a three-isotope diagram. When applying a second MS featuring a different ionization mechanism, we obtain a second isotope fractionation line with a different slope in the same three-isotope diagram. In both cases the absolute isotope ratios range somewhere on the isotope fractionation line. Consequentially, the intersect of both lines yield the absolute isotope ratios of the measured sample. This theory has been tested by measuring Cd and Pb isotope ratios of suitable isotope RMs with a TIMS and an ICP-MS, both equipped with multi-collector array. During the measurements the ionization conditions were changed such that different extent of the isotope fractionation has been achieved. With the resulting data set the theory described above could be verified. The obtained absolute isotope ratios were metrologically compatible with the certified isotope ratios. The remaining average bias of -5 ‰ can be reduced with further improvements. The calibration approach is universal and can be applied to any multi-isotopic element and it is not limited by the type of the mass spectrometer. T2 - Virtual Goldschmidt 2021 CY - Online meeting DA - 04.07.2021 KW - Absolute isotope ratio KW - Traceability KW - Metrology KW - Calibration KW - Uncertainty KW - Triple isotope fractionation PY - 2021 AN - OPUS4-53023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Backes, A. T. A1 - Reinmuth-Selzle, K. A1 - Leifke, A. L. A1 - Ziegler, K. A1 - Krevert, C. S. A1 - Tscheuschner, Georg A1 - Lucas, K. A1 - Weller, Michael G. A1 - Berkemeier, T. A1 - Pöschl, U. A1 - Fröhlich-Nowoisky, J. T1 - Oligomerization and Nitration of the Grass Pollen Allergen Phl p 5 by Ozone, Nitrogen Dioxide, and Peroxynitrite: Reaction Products, Kinetics, and Health Effects N2 - The allergenic and inflammatory potential of proteins can be enhanced by chemical modification upon exposure to atmospheric or physiological oxidants. The molecular mechanisms and kinetics of such modifications, however, have not yet been fully resolved. We investigated the oligomerization and nitration of the grass pollen allergen Phl p 5 by ozone (O3), nitrogen dioxide (NO2), and peroxynitrite (ONOO–). Within several hours of exposure to atmospherically relevant concentration levels of O3 and NO2, up to 50% of Phl p 5 were converted into protein oligomers, likely by formation of dityrosine cross-links. Assuming that tyrosine residues are the preferential site of nitration, up to 10% of the 12 tyrosine residues per protein monomer were nitrated. For the reaction with peroxynitrite, the largest oligomer mass fractions (up to 50%) were found for equimolar concentrations of peroxynitrite over tyrosine residues. With excess peroxynitrite, the nitration degrees increased up to 40% whereas the oligomer mass fractions decreased to 20%. Our results suggest that protein oligomerization and nitration are competing processes, which is consistent with a two-step mechanism involving a reactive oxygen intermediate (ROI), as observed for other proteins. The modified proteins can promote pro-inflammatory cellular signaling that may contribute to chronic inflammation and allergies in response to air pollution. KW - Protein KW - Nitrotyrosine KW - Dityrosine KW - Allergy KW - Hay fever KW - Diesel exhaust KW - Combustion KW - Exhaust PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529729 DO - https://doi.org/10.3390/ijms22147616 VL - 22 IS - 14 PB - MDPI CY - Basel AN - OPUS4-52972 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Stephan-Scherb, Christiane ED - Schorr, S. ED - Weidenthaler, C. T1 - Crystallographic challenges in corrosion research N2 - High-temperature corrosion is a widespread problem in various industries. As soon as a hot and reactive gas (CO2, O2, H2O, SO2, NOx, etc.) is in contact with a solid, physico-chemical processes at the surface and interfaces lead to material degradation. The processes are dynamic and controlled by thermodynamic and kinetic boundary conditions. Whether a reaction product is protective or not depends on various factors, such as chemical composition of the solid and the reactive media, surface treatment as well as diffusion and transport paths of cations and anions. Resulting chemical and structural inhomogeneities with the corrosion layers are characterized by off stoichiometry within cationic and anionic sub lattices. The competitive processes can be studied by various techniques of applied crystallography. This chapter gives an overview on the challenges of chemical-structural Analysis of reaction products by crystallographic methods such as X-ray diffraction and X-ray near-edge structure spectroscopy and scanning electron microscopy electron backscatter diffraction (SEM-EBSD) for corrosion science. KW - High-temperature corrosion KW - Oxidation KW - Diffraction KW - Spectroscopy KW - Oxides PY - 2021 DO - https://doi.org/10.1515/9783110674910-009 SP - 291 PB - De Gruyter ET - 1 AN - OPUS4-52903 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dinter, Adelina-Elisa ED - Dinter, Adelina-Elisa T1 - Development of a MIC single archaea-ICP-ToF-MS-method for analysis of various elements in solid steel samples N2 - With the latest ICP-MS technology - ICP-ToF (time of flight)-MS - it is possible to analyze the multi-element fingerprint of individual cells. The interface between material and environmental analysis thus receives special attention, e.g. when considering corrosion processes. Microbiologically influenced corrosion (MIC) is highly unpredictable due to the diversity of microbial communities involved. The development of the MIC-specific ICP-ToF-MS analytical method presented here at the single cell level, in combination with the investigation of steel-MIC interactions, contributes significantly to progress in instrumental MIC analysis and will enable clarification of the processes taking place. The supplied document shows the basis of a four minutes lightning talk. T2 - EuroMIC 2021 CY - Online meeting DA - 22.06.2021 KW - SC-ICP-ToF-MS KW - Single cell analysis KW - Microbiologically influenced corrosion KW - Lightning talk PY - 2021 AN - OPUS4-52905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Ponader, Marco A1 - Röder, Bettina A1 - Paul, Martin A1 - Weller, Michael G. T1 - Sintered glass monoliths as new supports for affinity columns N2 - A novel stationary phase for affinity separations is presented. This material is based on sintered borosilicate glass readily available as semi-finished filter plates with defined porosity and surface area. The material shows fast binding kinetics and excellent long-term stability under real application conditions due to lacking macropores and high mechanical rigidity. The glass surface can be easily modified with standard organosilane chemistry to immobilize selective binders or other molecules used for biointeraction. In this paper, the manufacturing of the columns and their respective column holders by 3D printing is shown in detail. The model system protein A/IgG was chosen as an example to examine the properties of such monolithic columns under realistic application conditions. Several specifications, such as (dynamic) IgG capacity, pressure stability, long-term performance, productivity, non-specific binding, and peak shape, are presented. It could be shown that due to the very high separation speed, 250 mg antibody per hour and column can be collected, which surpasses the productivity of most standard columns of the same size. The total IgG capacity of the shown columns is around 4 mg (5.5 mg/mL), which is sufficient for most tasks in research laboratories. The cycle time of an IgG separation can be less than 1 minute. Due to the glass material's excellent pressure resistance, these columns are compatible with standard HPLC systems. This is usually not the case with standard affinity columns, limited to manual use or application in low-pressure systems. The use of a standard HPLC system also improves the ability for automation, which enables the purification of hundreds of cell supernatants in one day. The sharp peak shape of the elution leads to an enrichment effect, which might increase the concentration of IgG by a factor of 3. The final concentration of IgG can be around 7.5 mg/mL without the need for an additional nanofiltration step. The purity of the IgG was > 95% in one step and nearly 99% with a second polishing run. KW - Affinity Chromatography KW - Glass KW - Purification KW - Antibodies KW - Solid support KW - HPLC KW - FPLC KW - Separation PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529117 DO - https://doi.org/10.20944/preprints202103.0298.v1 SN - 2310-287X N1 - Geburtsname von Ponader, Marco: Wilke, M. - Birth name of Ponader, Marco: Wilke, M. SP - 1 EP - 17 PB - MDPI CY - Basel AN - OPUS4-52911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Faßbender, Sebastian T1 - Mercury speciation in sediments of a historic industrially used canal in Northern Germany using SSID GC-ICP-ToF-MS N2 - Sediments and soils can act as sinks of species of inorganic mercury (Hg2+), while they are simultaneously sources of volatile (Hg0) and organic species, such as monomethylmercury (MMHg). Although the fraction of MMHg in total Hg of sediments is suggested to be as low as 0.1 1%, MMHg is a serious threat for humans and wildlife due to its high potential for bioaccumulation and biomagnification and the ability to pass the blood-brain barrier. This is highlighted by exceptionally high MMHg concentrations found in fish and fish predators, as well as aquatic insects and birds living in close vicinity to Hg contaminated waterbodies. Humans are exposed to MMHg mainly by ingestion of (predatory) fish and rice. One example of a highly Hg contaminated waterbody is Finow Canal, the oldest artificial waterway still in operation in Germany, with Hg mass fractions of up to or even more than 100 µg/g found in the sediment, which are suggested to be attributable to a chemical plant producing (among other things) mercury-based seed dressings. Despite this high mass fraction of Hg, anaerobic conditions, high amounts of organic matter and iron, which are all favorable for Hg methylation, no investigations of Hg speciation have been conducted there up to now. We investigated Hg speciation in sediments of Finow Canal on length from before the known polluted sited into the confluence with another waterway using species-specific isotope dilution (SSID) GC-ICP-ToF-MS. Mass fraction of up to 41 ng/g MMHg were determined in samples taken from Finow Canal and elevated concentrations could also be found around 14 km downstream of the confluence of Finow Canal with another waterway. In addition to this, highly toxic monoethylmercury (EtHg) could be detected in most of the sediment samples. These results are the first evidence of the occurrence of MMHg in this region and show the need for further investigation of the whole regional ecosystem, as well as the consideration of possible measures of remediation. T2 - Virtual Goldschmidt 2021 CY - Online meeting DA - 04.07.2021 KW - Methylmercury KW - Finow Canal KW - Legacy pollution KW - Isotope dilution PY - 2021 AN - OPUS4-52945 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Huan, Y. A1 - Gojani, Ardian A1 - Gornushkin, Igor B. A1 - Wang, X. A1 - Liu, D. A1 - Rong, M. T1 - Dynamics of laser-induced plasma splitting N2 - The dynamics of laser-induced plasma plume splitting is investigated using spatiotemporal plasma imaging and spectrometry in this paper. Plasma plume splitting into fast and slow components is clearly observed using plasma optical emission as time evolves. The spatial resolved plasma spectra are used to investigate the plasma species distribution, which reveals that the charged copper ions, which radiate at wavelength range 485 nm - 504 nm, are merely present in the fast component. In order to further interpret the mechanism, the pressure-dependent and laser energy-dependent plume splitting are analyzed. Based on the results, the charge separation field is proposed to explain this phenomenon. This work can be of importance for such areas as laser induced breakdown spectroscopy, laser-induced ion source formation, pulse laser deposition, film growth, and nanoscale synthesis. KW - Spectroscopy KW - Laser induced plasma KW - Splitting KW - Imaging PY - 2020 DO - https://doi.org/10.1016/j.optlaseng.2019.105832 SN - 0143-8166 VL - 124 SP - 1 EP - 5 PB - Elsevier CY - Amsterdam AN - OPUS4-48746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beckmann, Jörg A1 - Puskar, L. A1 - Ritter, E. A1 - Schade, U. T1 - Novel Technique for On-Line Monitoring of the Curing Process of Fiber Reinforced Polymer Composites N2 - A specially developed experimental set up has been integrated into a commercially available FT IR Spectrometer to study the curing of Epoxy Systems. MIR and FIR spectra measured during the curing process at different temperatures of an epoxy system will be presented in dependency of the curing time. The experiments and the selected set up are discussed to demonstrate its potential for future monitoring and ageing control applications during a manufacturing process of polymer composites. T2 - 45. International conference on infrared, millimeter, and terahertz waves CY - Online meeting DA - 08.11.2020 KW - Far-infrared spectroscopy KW - Online Curing Monitoring PY - 2021 SN - 978-1-7281-6620-9 DO - https://doi.org/10.1109/irmmw-thz46771.2020.9370646 SP - 1 PB - IEEE AN - OPUS4-53059 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Karafiludis, Stephanos T1 - Crystallisation and nucleation study of transition metal struvite and related compounds N2 - The recycling of critical elements has crucial importance to maintain sustainable use of raw materials. Phosphorus(P) is a sought-after limited natural resource due to its wide use in modern agriculture mainly as P-fertilizers. But it causes major problems for the environment such as eutrophication of ecosystems. In the future it could be depleted due to the high demand and declining natural phosphorite ore deposits. Therefore, the phosphorus recovery from agricultural waste waters will be an important factor in preservation of the global consumption. The precipitation of M-struvite (NH4MPO4·6H2O, M2+= Mg2+, Ni2+, Co2+, Zn2+, Cu2+ etc.) from agricultural and mine waste waters is a promising P-recovery route. Besides avoidance of eutrophication due to extraction of excess phosphates and the restoration of the phosphorus resources the recovered M-struvites may be potentially be up-cycled for industrial applications e.g. Co and Ni-phosphate show excellent electrochemical properties for batteries or supercapacitors. The precipitation processes of M-struvites are strongly dependent on the degree of supersaturation, pH and on the exchange ions M2+.The impact of transition metals on the crystallization of M-struvite has been investigated only to a limited extent. An optimization of the reaction conditions could lead to more efficient M-struvite precipitation and significantly improved P-recovery method. In addition, these materials form transitional amorphous colloidal nanophases on the way to the crystalline product indicating a non-classical crystallization pathway. By interfering the crystallization process a potential highly reactive amorphous precursor material can be preserved for electrocatalysis. Here, we present hints on the crystallization mechanism and the kinetics of precipitation through analysis of the transitional phases. Furthermore, we reveal the effect of different reaction conditions on the crystal shape and crystallite size of M-struvites (NH4MPO4∙6H2O, M = Mg2+, Ni2+, Co2+). In addition, we could evaluate the stability of crystalline M-struvites and their related phases through characterization of the coordination environment [Co-dittmarite (COD) NH4CoPO4∙H2O and Cobalt(II)phosphate octahydrate (CPO) Co3(PO4)2∙8H2O].Due to the low solubility product and their controlled precipitation through adjusting the reaction conditions (c(educts), pH, multi metal solutions) M-struvite is a promising recovery material as it could extract NH4+, PO43- and heavy metals at the same time out of agricultural and mine waste waters. T2 - IUCr 25th International Union of Crystallography Congress CY - Online meeting DA - 14.08.2021 KW - Crystal Engineering KW - Nucleation KW - Amorphous Phases KW - Crystal mechanism PY - 2021 AN - OPUS4-53445 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Karafiludis, Stephanos T1 - Crystallisation and nucleation study of transition metal phosphates: M-struvite and related compounds N2 - The recycling of critical elements has crucial importance to maintain sustainable use of raw materials. Phosphorus(P) is a sought-after limited natural resource due to its wide use in modern agriculture mainly as P-fertilizers. But it causes major problems for the environment such as eutrophication of ecosystems. In the future it could be depleted due to the high demand and declining natural phosphorite ore deposits. Therefore, the phosphorus recovery from mine and agricultural waste waters will be an important factor in preservation of the global consumption. The precipitation of M-struvite (NH4MPO4·6H2O, M2+= Mg2+, Ni2+, Co2+) from waste waters is a promising P-recovery route. Besides avoidance of eutrophication due to extraction of excess phosphates and the restoration of the phosphorus resources the recovered M-struvites may be potentially be up-cycled for industrial applications e.g. Co and Ni-phosphate show excellent electrochemical properties for batteries or supercapacitors. The precipitation process of M-struvites is strongly dependent on the degree of supersaturation, pH and on the exchange ions M2+.The influence of these precipitation parameters on the crystal morphology and size of transition metal struvite has been investigated only to a limited extent. An optimization of the reaction conditions could lead to more efficient M-struvite precipitation and significantly improved P-recovery method. We reveal the effect of different reaction conditions on the crystal shape and crystallite size of M-struvites (NH4MPO4∙6H2O, M = Mg2+, Ni2+, Co2+). Furthermore, we characterize the coordination environment of the crystalline end products and their related phases [Co-dittmarite (COD) NH4CoPO4∙H2O and Co(II)phosphate octahydrate (CPO) Co3(PO4)2∙8H2O]. Due to the presence of various amorphous phases pH is changing significantly in the different systems. Mg- and Ni-struvite are stable in multiple concentrations of the educts and metal/phosphorus (M/P) ratios in contrast to Co-struvite which forms below M/P ratios of 0.4. A high M/P ratio with high concentrations of the educts decrease the crystallite size and idiomorphism of the crystals while low M/P ratios with low concentrations of the educts increase the crystallite size and the euhedral formation of the crystal planes. In the (Ni, Co)-solid solutions Ni and Co are homogenously distributed in the crystals with similar Ni# as in the aqueous solutions indicating no elemental fractionation in crystallization. Ni and Co-struvite exhibit a more centrosymmetric coordination environment compared to their related phases of COD and CPO determined by EXAFS. The CoO6 octahedron expands slightly the ideal size of the struvite structure and decomposes to Co-dittmarite. From TEM analysis and pH measurements it is suggested that the crystallization of Ni- and Co-struvite follows a non-classical crystallization theory which consists of multiple nanophases, crystalline or amorphous, on the way to the final crystalline product. T2 - Goldschmidt Conference 2021 CY - Online meeting DA - 04.07.2021 KW - Crystal Engineering KW - Nucleation KW - Amorphous Phases KW - Crystal mechanism PY - 2021 UR - https://2021.goldschmidt.info/goldschmidt/2021/meetingapp.cgi/Paper/5288 AN - OPUS4-53446 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schnur, C. T1 - Explainable machine learning for damage detection - In carbon fiber composite plates under varying temperature conditions N2 - Understanding on how a machine learning model interprets data is a crucial step to verify its reliability and avoid overfitting. While the focus of the scientific community is nowadays orientated towards deep learning approaches, which are considered as black box approaches, this work presents a toolbox that is based on complementary methods of feature extraction and selection, where the classification decisions of the model are transparent and can be physically interpreted. On the example of guided wave benchmark data from the open guided waves platform, where delamination defects were simulated at multiple positions on a carbon fiber reinforced plastic plate under varying temperature conditions, the authors could identify suitable frequencies for further investigations and experiments. Furthermore, the authors presented a realistic validation scenario which ensures that the machine learning model learns global damage characteristics rather than position specific characteristics. T2 - 48th Annual Review of Progress in Quantitative Nondestructive Evaluation CY - Online meeting DA - 28.07.2021 KW - Machine Learning KW - Guided waves KW - Damage Detection KW - Structural Health Monitoring KW - Composite Structures PY - 2021 AN - OPUS4-53377 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - VIDEO A1 - Pauw, Brian Richard T1 - The SAXS platform at BAM N2 - Presentation of the Small-Angle X-Ray Scattering intrument at BAM (Berlin - Germany). More information about SAXS is available on Brian Pauw's long-running SAXS blog: https://lookingatnothing.com/ KW - X-ray scattering KW - MOUSE KW - Instrumentation KW - SAXS KW - Laboratory PY - 2021 UR - https://www.youtube.com/watch?v=OjYToZQTsqo PB - YouTube, LLC CY - San Bruno, CA, USA AN - OPUS4-53358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Duwe, M. T1 - Thickness Profiling of the Superficial Amorphization and Re-Crystallization of Silicon Induced by Femtosecond Laser Pulses N2 - Crystalline Silicon undergoes a complex phase-change dynamic of melting, amorphization, ablation and re-crystallization upon irradiation with high intensity ultra-short laser pulses [1]. The final state of such a modified surface spot depends on many factors, most notably the local fluence and the surface’s crystal orientation. In this study, we induced superficial structure and phase changes in Silicon <111> and <100> wafers using single femtosecond laser pulses (790 nm, 30 fs) for a range of different peak fluences. The resulting surface modifications were studied in great detail using a number of different techniques, including spectroscopic imaging ellipsometry (SIE), atomic force microscopy, high-resolution transmission electron microscopy (HRTEM), and energy dispersive X-ray spectroscopy within scanning transmission electron microscopy (STEM-EDX). Playing a pivotal role in this work, SIE provided non-destructive measurements for the calculation of the radial amorphous layer-thickness profiles of the irradiated spots using a two-layer thin-film model (Silicon dioxide and amorphous Silicon on a crystalline Silicon substrate). The measurements further allowed for the analysis of the oxide-layer modifications induced by the laser treatment. The results of the SIE-calculations were cross-checked by an in-depth material lamella via HRTEM and STEM-EDX. T2 - 11th Workshop Ellipsometry (WSE 11) CY - Steyr, Austria DA - 06.09.2021 KW - Femtosecond Laser KW - Spectroscopic imaging ellipsometry KW - Amorphization KW - Ablation KW - Re-crystallization PY - 2021 AN - OPUS4-53363 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baensch, Franziska T1 - Acoustic emission of fibre reinforced AlSi12CuMgNi alloy under compression N2 - Typically, the near-eutectic Al-Si alloys consist of highly interconnected three-dimensional network of the eutectic Silicon (Si) and intermetallics embedded into Aluminium (Al) matrix. For further improvement of the mechanical properties of such alloys, often, one single ceramic reinforcement phase, e.g. silicon carbide (SiC) or aluminium oxide (Al2O3) in the form of fibres or particles is added. However, hybrid reinforcements (fibres and particles) can further improve wear resistance and fracture toughness, and additionally, reduce anisotropy of the material. The engineering of metal matrix composites (MMC) for specific application requirements benefits from a comprehensive knowledge of the failure behaviour. Therefore, damage evolution under compression was investigated on: - pure near-eutectic AlSi12CuMgNi matrix alloy - type I: matrix reinforced with random-planar oriented Al2O3 short fibres (15 vol.%) - type II: matrix reinforced with random-planar oriented Al2O3 short fibres (7 vol.%) and additional SiC particles (15 vol.%) The analysis of damage mechanism was carried out in two rather independent but complementary studies. First, selected sister samples of every material were exposed to quasi-static compression (traverse control). The compression tests were interrupted at different strain levels. Miniature cylinders with a diameter of 1mm were extracted from the pre-strained samples and investigated by synchrotron computed tomography (SX-µCT) with a spatial resolution of about 0.7 µm. For the pure matrix alloy, microcracks are confined to the intermetallic particles and to the eutectic Si, hence no damage was observed in the Aluminium. The composite type II revealed a more effective strain accumulation (less damage) than type I at low plastic strain (up to 5 %), but a more catastrophic damage development due to cracking of the SiC clusters at higher strain levels. The second approach to study the damage initiation and accumulation in the materials subjected to compressive load was Acoustic Emission (AE) analysis. In this case the in-situ monitoring of the acoustic emission signal was performed during compression tests on specimens with dimension of several mm. For all three material types, AE activity set at 2% strain. Differences in AE behaviour of the three materials was proven based on AE hitrate, signal peak amplitudes as well as weighted peak frequencies (WPF). Future work focuses on combination of AE and SX-µCT aiming for more detailed knowledge on damage mechanism of metal matrix composites. T2 - Schall21 CY - Online meeting DA - 24.02.2021 KW - AlSi12CuMgNi KW - Al-Si alloys KW - Acoustic emission KW - Tension PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-534268 UR - https://www.dgzfp.de/seminar/schall21 AN - OPUS4-53426 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meermann, Björn T1 - Von Elementspezies, Isotope und Zellen oder: wie kommt man eigentlich von Westfalen nach Berlin N2 - Im Rahmen des Vortrages werden die Möglichkeiten der Elementanalytik an Applikationsbeispielen aus Umwelt und life-sciences aufgezeigt. Hierbei kommen ICP-MS Kopplungstechniken, stabile Isotope und Einzellen- und Partikelanalytik (sc-/sp-ICP-ToF-MS) zum Einsatz. T2 - DAAS PhD Seminar CY - Online meeting DA - 20.09.2021 KW - Elementspezies & Isotope KW - ICP-MS & HR-CS-GFMAS KW - Kopplungstechniken PY - 2021 AN - OPUS4-53378 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meermann, Björn T1 - On-line hyphenation of CE with multicollector-icp-ms for species-specific isotopic analysis of sulfur N2 - In many scientific fields, isotopic analysis can offer valuable information, e.g., for tracing the origin of food products, environmental contaminants, forensic and archaeological samples (provenance determination), for age determination of minerals (geochronological dating) or for elucidating chemical processes. Up to date, typically bulk analysis is aimed at measuring the isotopic composition of the entire elemental content of the sample. However, the analyte element is usually present under the form of different species. Thus, separating species of interest from one another and from matrix components prior to isotope ratio measurements can provide species-specific isotopic information, which could be used for tracing the origin of environmental pollutants and elucidation of (environmental) speciation. Using on-line hyphenations of separation techniques with multicollector-ICP-MS (MC-ICP-MS) can save time and effort and enables the analysis of different species during a single measurement. In this work, we developed an on-line hyphenation of CE with multicollector-ICP-MS (CE/MC-ICP-MS) for isotopic analysis of sulfur species using a multiple-injection approach for instrumental mass bias correction by standard-sample bracketing. With this method, the isotopic composition of sulfur in sulfate originating from river water could be analyzed without sample preparation. The results were compared to data from off-line analysis of the same samples to ensure accuracy. The precision of the results of the on-line measurements was promising regarding the differentiation of the river systems by the isotopic signature of river water sulfate. The great potential of this method is based on the versatility of the applied separation technique, not only in the environmental field but also for, e.g., biomolecules, as sulfur is the only covalently bound constituent of proteins that can be analyzed by MC-ICP-MS. T2 - 12th International Conference on Instrumental Methods of Analysis-Modern Trends and Applications (IMA) CY - Online meeting DA - 20.09.2021 KW - CE/MC-ICP-MS KW - Species-specific Isotope Analysis KW - Environmental & life science application KW - Speciation Analysis PY - 2021 AN - OPUS4-53379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Haeckel, A. A1 - Ascher, Lena A1 - Beindorff, N. A1 - Prasad, S. A1 - Garczynska, K. A1 - Guo, J. A1 - Schellenberger, E. T1 - Long‑circulating XTEN864‑annexin A5 fusion protein for phosphatidylserine‑related therapeutic applications N2 - Annexin A5 (anxA5) is a marker for apoptosis, but has also therapeutic potential in cardiovascular diseases, cancer, and, due to apoptotic mimicry, against dangerous viruses, which is limited by the short blood circulation. An 864-amino-acid XTEN polypeptide was fused to anxA5. XTEN864-anxA5 was expressed in Escherichia coli and purified using XTEN as tag. XTEN864-anxA5 was coupled with DTPA and indium-111. After intravenous or subcutaneous injection of 111In-XTEN864-anxA5, mouse blood samples were collected for blood half-life determination and organ samples for biodistribution using a gamma counter. XTEN864-anxA5 was labeled with 6S-IDCC to confirm binding to apoptotic cells using flow cytometry. To demonstrate targeting of atherosclerotic plaques, XTEN864-anxA5 was labeled with MeCAT(Ho) and administered intravenously to atherosclerotic ApoE−/−mice. MeCAT(Ho)-XTEN864-anxA5 was detected together with MeCAT(Tm)-MAC-2 macrophage antibodies by imaging mass cytometry (CyTOF) of aortic root sections. The ability of anxA5 to bind apoptotic cells was not affected by XTEN864. The blood half-life of XTEN864-anxA5 was 13 h in mice after IV injection, markedly longer than the 7-min half-life of anxA5. 96 h after injection, highest amounts of XTEN864-anxA5 were found in liver, spleen, and kidney. XTEN864-anxA5 was found to target the adventitia adjacent to atherosclerotic plaques. XTEN864-anxA5 is a long-circulating fusion protein that can be efficiently produced in E. coli and potentially circulates in humans for several days, making it a promising therapeutic drug. KW - Programmed cell death KW - LA/ICP-MS Imaging KW - Medicinal application PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-533811 DO - https://doi.org/10.1007/s10495-021-01686-w VL - 26 IS - 9-10 SP - 534 EP - 547 PB - Springer AN - OPUS4-53381 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fink, Friedrich A1 - Emmerling, Franziska A1 - Falkenhagen, Jana T1 - Identification and Classification of Technical Lignins by means of Principle Component Analysis and k-Nearest Neighbor Algorithm N2 - The characterization of technical lignins is a key step for the efficient use and processing of this material into valuable chemicals and for quality control. In this study 31 lignin samples were prepared from different biomass sources (hardwood, softwood, straw, grass) and different pulping processes (sulfite, Kraft, organosolv). Each lignin was analysed by attenuated total reflectance Fourier transform infrared (ATR-FT-IR) spectroscopy. Statistical analysis of the ATR-FT-IR spectra by means of principal component analysis (PCA) showed significant differences between the lignins. Hence, the samples can be separated by PCA according to the original biomass. The differences observed in the ATR-FT-IR spectra result primarily from the relative ratios of the p-hydroxyphenyl, guaiacyl and syringyl units. Only limited influence of the pulping process is reflected by the spectral data. The spectra do not differ between samples processed by Kraft or organosolv processes. Lignosulfonates are clearly distinguishable by ATR-FT-IR from the other samples. For the classification a model was created using the k-nearest neighbor (k NN) algorithm. Different data pretreatment steps were compared for k=1…20. For validation purposes, a 5-fold cross-validation was chosen and the different quality criteria Accuracy (Acc), Error Rate (Err), Sensitivity (TPR) and specificity (TNR) were introduced. The optimized model for k=4 gives values for Acc = 98.9 %, Err = 1.1 %, TPR = 99.2 % and TNR = 99.6 %. KW - Classification KW - PCA KW - K-nearest neighbor KW - FT-IR KW - Technical lignin PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-533855 DO - https://doi.org/10.1002/cmtd.202100028 VL - 1 IS - 8 SP - 350 EP - 396 PB - Wiley-VCH GmbH AN - OPUS4-53385 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meermann, Björn T1 - The future of elemental analytical chemistry – the sixth special issue dedicated to young analytical scientists N2 - Editorial for a special issue KW - Editorial KW - Special issue, young analytical scientists KW - Elemental analysis PY - 2021 DO - https://doi.org/10.1039/d1ja90038b VL - 36 IS - 9 SP - 1794 EP - 1796 PB - RSC AN - OPUS4-53086 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mirabella, Francesca A1 - Müllner, M. A1 - Touzalin, T. A1 - Riva, M. A1 - Jakub, Z. A1 - Kraushofer, F. A1 - Schmid, M. A1 - Koper, M. T. M. A1 - Parkinson, G. S. A1 - Diebold, U. T1 - Ni-modified Fe3O4(001) surface as a simple model system for understanding the oxygen evolution reaction N2 - Electrochemical water splitting is an environmentally friendly technology to store renewable energy in the form of chemical fuels. Among the earth-abundant first-row transition metal-based catalysts, mixed Ni-Fe oxides have shown promising performance for effective and low-cost catalysis of the oxygen evolution reaction (OER) in alkaline media, but the synergistic roles of Fe and Ni cations in the OER mechanism remain unclear. In this work, we report how addition of Ni changes the reactivity of a model iron oxide catalyst, based on Ni deposited on and incorporated in a magnetite Fe3O4(001) single crystal, using a combination of surface science techniques in ultra-high vacuum such as low energy electron diffraction (LEED), x-ray photoelectron spectroscopy (XPS), low-energy ion scattering (LEIS), and scanning tunneling microscopy (STM), as well as atomic force microscopy (AFM) in air, and electrochemical Methods such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in alkaline media. A significant improvement in the OER activity is observed when the top surface presents an iron fraction among the cations in the range of 20-40%, which is in good agreement with what has been observed for powder catalysts. Furthermore, a decrease in the OER overpotential is observed following surface aging in electrolyte for three days. At higher Ni load, AFM shows the growth of a new phase attributed to an (oxy)-hydroxide phase which, according to CV measurements, does not seem to correlate with the surface activity towards OER. EIS suggests that the OER precursor species observed on the clean and Ni-modified surfaces are similar and Fe-centered, but form at lower overpotentials when the surface Fe:Ni ratio is optimized. We propose that the well-defined Fe3O4(001) surface can serve as a model System for understanding the OER mechanism and establishing the structure-reactivity relation on mixed Fe-Ni oxides. KW - OER KW - Fe-Ni oxides KW - Surface science KW - Electrochemistry KW - Water splitting PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529231 UR - https://www.sciencedirect.com/science/article/pii/S0013468621009282?via%3Dihub DO - https://doi.org/10.1016/j.electacta.2021.138638 VL - 389 SP - 138638 PB - Elsevier Ltd. AN - OPUS4-52923 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tang, Chi-Long T1 - Chemical characterization of ultrafine particles released from 3D printers N2 - Previous studies have shown that desktop 3D printers (Fused Filament Fabrication) emit high numbers of particulate matter, mainly as ultrafine particles (UFP, particle diameter less than 100 nm). However, the chemical composition of emitted particles has been less extensively investigated. In this study, we therefore focused on the chemical composition of particles emitted from 3D printing. The measurements were conducted in a 1 m³ emission test chamber. Emitted particles were sampled by a 13-stage low-pressure cascade impactor onto aluminum foils and then analyzed by TD-GC/MS to identify their organic compounds. Nine commercial filaments made from basic polymers such as Acrylonitrile Butadiene Styrene (ABS), Acrylonitrile Styrene Acrylate (ASA), Polycarbonate (PC), Poly(methyl methacrylate) (PMMA), Nylon, High Performance Polystyrene (HIPS) and a copper-filled Polylactide (PLA) were investigated. The results show that the organic components of the particles are primarily plastic additives such as plasticizer, antioxidant agents, lubricants, UV-absorbers and UV-stabilizers from the filaments. T2 - Healthy Buildings Europe 2021 CY - Online meeting DA - 21.06.2021 KW - UFP KW - FFF-3D-Printer KW - Chemical characterization PY - 2021 AN - OPUS4-52895 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jurgelucks, B. T1 - Defect Characterization in Carbon Fiber Reinforced Polymer via Derivative-based Optimization N2 - In recent years carbon über polymers have become a popular light-weight substitute for high-weight materials such as steel. One advantage of carbon fiber polymers is the high strength-to-weight ratio, thus some popular application areas are weight sensitive such as aeronautics or automobiles. As these application areas are especially sensitive to material failure it is of significant interest to characterize material defects which may arise. In this talk we will propose a method to characterize material defects in carbon fiber reinforced polymers using gradient-based optimization methods. The procedure is based on the solution of an inverse problem where simulation data and experimental data is fitted. Here, gradients of the simulation will be supplied by an Algorithmic Differentiation (AD) tool which greatly enhances the quality of the solution. Numerical examples will be provided. T2 - GAMM 2020@21 CY - Online meeting DA - 15.03.2021 KW - Inverse Method KW - Scaled Boundary Finite Element Method KW - Algorithmic Differentiation PY - 2021 AN - OPUS4-52896 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gehrenkemper, Lennart T1 - Finding the most suitable PFASs sum parameter method - A Comparison of AOF vs. EOF and CIC vs. HR-CS-GFMAS N2 - Since it is unknown for many applications, which PFASs are used and how they enter the environment, target analysis-based methods reach their limits. The two most frequently used sum parameters are the adsorbable organically bound fluorine (AOF) and the extractable organically bound fluorine (EOF). Both can be quantified using either combustion ion chromatography (CIC) or high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS). Here we provide an insight on the advantageous and disadvantageous of both sum parameters and both detection methods. Our study is based on the analysis of surface water samples. Next to total fluorine (TF) analysis, AOF and EOF were determined as well as CIC and HR-CS-GFMAS are compared and results are comparatively discussed. Fluorine mass balancing revealed that, the AOF/TF proportion was higher than the EOF/TF proportion. The AOF made up 0.14–0.81% of TF and the EOF 0.04–0.28% of TF. Although, organically bound fluorine represents only a small portion of TF, PFASs are of worldwide concern, because of their extreme persistence and their bioaccumulation potential. The EOF-HR-CS-GFMAS method turned out to be more precise and sensitive than the AOF-CIC method and is a promising tool for future monitoring studies/routine analysis of PFASs in the environment. T2 - Emerging Contaminants in the Environment Conference CY - Online meeting DA - 27.04.2021 KW - High resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) KW - Combustion ion chromatography (CIC) KW - Per- and polyfluorinated alkyl substances (PFASs) KW - Adsorbable organically bound fluorine (AOF) KW - Extractable organically bound fluorine (EOF) PY - 2021 AN - OPUS4-53228 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dariz, P. A1 - Schmid, Thomas T1 - Trace compounds in Early Medieval Egyptian blue carry information on provenance, manufacture, application, and ageing N2 - Only a few scientific evidences for the use of Egyptian blue in Early Medieval wall paintings in Central and Southern Europe have been reported so far. The monochrome blue fragment discussed here belongs to the second church building of St. Peter above Gratsch (South Tyrol, Northern Italy, fifth/ sixth century A.D.). Beyond cuprorivaite and carbon black (underpainting), 26 accessory minerals down to trace levels were detected by means of Raman microspectroscopy, providing unprecedented insights into the raw materials blend and conversion reactions during preparation, application, and ageing of the pigment. In conjunction with archaeological evidences for the manufacture of Egyptian blue in Cumae and Liternum and the concordant statements of the antique Roman writers Vitruvius and Pliny the Elder, natural impurities of the quartz sand speak for a pigment produced at the northern Phlegrean Fields (Campania, Southern Italy). Chalcocite (and chalcopyrite) suggest the use of a sulphidic copper ore, and water-insoluble salts a mixed-alkaline flux in the form of plant ash. Not fully reacted quartz crystals partly intergrown with cuprorivaite and only minimal traces of silicate glass portend solid-state reactions predominating the chemical reactions during synthesis, while the melting of the raw materials into glass most likely played a negligible role. KW - Egyptian blue KW - Raman microspectroscopy KW - Spectoscopic imaging KW - Cuprorivaite KW - Amorphous carbon PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537591 DO - https://doi.org/10.1038/s41598-021-90759-6 VL - 11 SP - 1 EP - 12 PB - Nature Portfolio AN - OPUS4-53759 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmid, Thomas A1 - Kraft, Ronja A1 - Dariz, P. T1 - Shedding light onto the spectra of lime - Part 2: Raman spectra of Ca and Mg carbonates and the role of d-block element luminescence N2 - We previously described the observation of a characteristic narrowband red luminescence emission of burnt lime (CaO), whose reason was unknown so far. This study presents Raman spectra of Mg5 CO3)4(OH)2∙4H2O, Mg5(CO3)4(OH)2, MgCO3, CaMgCO3 and CaCO3 (in limestone powder) as well as luminescence spectra of their calcination products. Comparison of the latter revealed MgO:Cr3+ as the source of the red lime luminescence in all studied samples, containing magnesium oxide as major component, minor component or trace. Spectral characteristics and theoretical background of the luminescence emission of d-block elements integrated in crystal lattices are discussed with the aim of sharpening the awareness for this effect in the Raman community and promoting its application in materials analysis. The latter is demonstrated by the Raman microspectroscopic imaging of the distributions of both Raman-active and Raman-inactive phases in clinker remnants in a 19th-century meso Portland cement mortar sample, which contain relatively high amounts of free lime detected in the form of both luminescing CaO and Raman-scattering Ca(OH)2, owing to exposure of the surface of the thin section to humid air. A combination of light and Raman spectroscopy revealed a calcium–magnesium–iron sulphide phase, indicating sulphurous raw materials and/or solid fuels employed in the calcination process, which in contrast to previously described morphologies of sulphides in cement clinker form extensive greenish black layers on free lime crystals. KW - Calcium carbonates KW - Raman spectroscopy KW - Luminescence KW - Magnesium carbonates KW - Meso Portland cement PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537611 DO - https://doi.org/10.1002/jrs.6174 SN - 0377-0486 VL - 52 IS - 8 SP - 1462 EP - 1472 PB - Wiley Analytical Science AN - OPUS4-53761 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zeipert, H. A1 - Claes, L. A1 - Johannesmann, S. A1 - Lugovtsova, Yevgeniya A1 - Nicolai, Marcel A1 - Prager, Jens A1 - Henning, Bernd ED - Jumar, U. T1 - An approach to adhesive bond characterisation using guided acoustic waves in multi-layered plates N2 - An approach for the non-destructive characterisation of adhesive bonds using guided ultrasonic waves is presented. Pulsed laser radiation is used to thermoacoustically excite broadband ultrasonic waves in a multi-layered sample, consisting of a metal plate adhesively joined to a polymeric layer using synthetic resin. The resulting signals are received by a purpose-built piezoelectric transducer. Varying the distance between excitation and detection yields spatio-temporal measurement data, from which the dispersive properties of the propagating waves can be inferred using a two-dimensional Fourier transform, assuming the plates to act as coupled waveguides. Coupled multi-layered waveguides show an effect referred to as mode repulsion, where the distance between certain modes in the frequency-wavenumber domain is assumed to be a measure of coupling strength. Measurements at different stages of curing of the adhesive layer are performed and evaluated. A comparison of the results shows changes in the dispersive properties, namely an increased modal bandwidth for the fully cured sample as well as an increased modal distance. KW - Adhesive bonding KW - Guided waves KW - Non-destructive testing KW - Ultrasound PY - 2021 DO - https://doi.org/10.1515/auto-2021-0089 VL - 69 IS - 11 SP - 962 EP - 969 PB - De Gruyter CY - Berlin/Boston AN - OPUS4-53762 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmid, Thomas A1 - Hidde, Julia A1 - Grünier, Sophie A1 - Jungnickel, Robert A1 - Dariz, P. A1 - Riedel, Jens A1 - Neuhaus, B. T1 - Ageing effects in mountig media of microscope slide samples from natural history collections: A case study with Canada balsam and Permount™ N2 - Microscope slide collections represent extremely valuable depositories of research material in a natural history, forensic, veterinary, and medical context. Unfortunately, most mounting media of these slides deteriorate over time, with the reason for this not yet understood at all. In this study, Raman spectroscopy, ultraviolet–visible (UV–Vis) spectroscopy, and different types of light microscopy were used to investigate the ageing behaviour of naturally aged slides from museum collections and the experimentally aged media of Canada balsam and Permount™, representing a natural and a synthetic resin, respectively, with both being based on mixtures of various terpenes. Whereas Canada balsam clearly revealed chemical ageing processes, visible as increasing colouration, Permount™ showed physical deterioration recognisable by the increasing number of cracks, which even often impacted a mounted specimen. Noticeable changes to the chemical and physical properties of these mounting media take decades in the case of Canada balsam but just a few years in the case of Permount™. Our results question whether or not Canada balsam should really be regarded as a mounting medium that lasts for centuries, if its increasing degree of polymerisation can lead to a mount which is no longer restorable. KW - Deterioration KW - Microscope slides KW - Mounting media KW - Raman spectroscopy KW - UV–Vis spectroscopy PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537632 DO - https://doi.org/10.3390/polym13132112 VL - 13 IS - 13 SP - 1 EP - 27 PB - MDPI CY - Basel AN - OPUS4-53763 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gornushkin, Igor B. T1 - model of laser induced plasma relevant to structuring and coating of titanium implants N2 - The presentation will give a brief overview of the processes occurring in laser-induced plasma and methods of modeling these processes. In particular, a chemical-hydrodynamic model will be considered, which is related to the modification of the surface of metallic titanium by laser pulses. The details and simplifications of this model, its shortcomings and the possibilities of their elimination will be discussed. This model is related to the structuring of the surface of dental implants with a laser and the deposition of an oxide film on it. T2 - THE 2-nd THEMATIC INTERNATIONAL SCIENTIFIC AUTUMN SCHOOL ON LASER MICRO- & NANOTHECHNOLOGIES: 2021 – BIOMEDICAL TECHNOLOGIES CY - St. Petersburg, Russia DA - 09.11.2021 KW - Laser ablation KW - Laser induced plasma deposition KW - Surface coating KW - Emission spectroscopy KW - Hydrodynamic model KW - Plasma chemistry PY - 2021 AN - OPUS4-53718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe T1 - Uncertainty budgets in surface techno-logy: step height, layer thickness, indentation hardness, adehesive strength N2 - The object (sample) and the measurement/testing procedure may always have unknown degrees of freedom, i.e. instead of 𝐯 ≥ n – 1 in many cases 𝐯 ≫ n - 1 may apply, in particular in the micro- and nano-world! T2 - 10. VDI-Fachtagung, Messunsicherheit und Prüfprozesse CY - Erfurt, Germany DA - 10.11.2021 KW - Methodology in metrology KW - Methodology in testing KW - Spectroscopic Ellipsometry KW - Instrumented Indentation (IIT) KW - Centrifugal Adhesion Testing (CAT) PY - 2021 AN - OPUS4-53739 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ogrinc, N. A1 - Rossi, A. M. A1 - Durbiano, F. A1 - Becker, Roland A1 - Milavec, M. A1 - Bogozalec Kosir, A. A1 - Kakoulides, E. A1 - Ozer, H. A1 - Akcadag, F. A1 - Goenaga-Infante, H. A1 - Quaglia, M. A1 - Mallia, S. A1 - Umbricht, G. A1 - O'Connor, G. A1 - Guettler, B. T1 - Support for a European metrology network on food safety Food-MetNet N2 - This paper describes Food-MetNet, a coordinated preparatory initiative to establish the European Metrology Network on Food Safety (EMN-FS). Food-MetNet aims to establish a long-term ongoing dialogue between the metrology community and relevant stakeholders, in particular, European Union Reference Laboratories (EURLs), National Reference Laboratories (NRLs) and the Joint Research Centre (JRC). This dialogue is meant to support the collection of needs from stakeholders, the take-up of metrological research output and the development of the roadmaps needed to navigate future research. KW - Network KW - Metrology KW - Food KW - Safety KW - Stakeholders PY - 2021 DO - https://doi.org/10.1016/j.measen.2021.100285 VL - 18 SP - 1 EP - 4 PB - Elsevier AN - OPUS4-53740 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Heyn, L. A1 - Jung, Christian T1 - Indoor exposure to airborne polycyclic aromatic hydrocarbons: A comparison of stir bar sorptive extraction and pump sampling N2 - Stir bar sorptive extraction (SBSE) was compared with standardized pump sampling regarding the prospects to assess airborne levels of polycyclic aromatic hydrocarbons (PAHs) in indoor environments. A historic railway water tower, which will be preserved as a technical monument for museum purposes, was sampled with both approaches because the built-in insulationmaterial was suspected to release PAHs to the indoor air. The 16 PAHs on the US EPA list were quantified using gas chromatography with mass spectrometric detection in filters from pump sampling after solvent extraction and on SBSE devices after thermal desorption. SBSEwas seen to sample detectable PAHmasseswith excellent repeatability and a congener pattern largely similar to that observed with pump sampling. Congener patterns were however significantly different from that in the PAH source because release from the insulation material is largely triggered by the respective congener vapor pressures. Absolute masses in the ng range sampled by SBSE corresponded to airborne concentrations in the ng L−1 range determined by pump sampling. Principle differences between SBSE and pump sampling as well as prospects of SBSE as cost-effective and versatile complement of pump sampling are discussed. KW - Polycyclic aromatic hydrocarbons KW - Adsorption KW - Extraction KW - Indoor air PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537427 DO - https://doi.org/10.1002/eng2.12419 VL - 3 IS - 12 SP - 1 EP - 10 PB - John Wiley & Sons Ltd. AN - OPUS4-53742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lecompagnon, Julien A1 - Ahmadi, Samim A1 - Hirsch, Philipp Daniel A1 - Rupprecht, C. A1 - Ziegler, Mathias ED - Kimata, M. ED - Shaw, J. A. ED - Valenta, C. R. T1 - Investigations on photothermal super resolution reconstruction using 2D-structured illumination patterns N2 - Active thermography as a nondestructive testing modality suffers greatly from the limitations imposed by the diffusive nature of heat conduction in solids. As a rule of thumb, the detection and resolution of internal defects/inhomogeneities is limited to a defect depth to defect size ratio greater than or equal to one. Earlier, we demonstrated that this classical limit can be overcome for 1D and 2D defect geometries by using photothermal laser-scanning super resolution. In this work we report a new experimental approach using 2D spatially structured illumination patterns in conjunction with compressed sensing and computational imaging methods to significantly decrease the experimental complexity and make the method viable for investigating larger regions of interest. T2 - Future Sensing Technologies Conference 2021 CY - Online meeting DA - 15.11.2021 KW - Thermography KW - Super resolution KW - NDT KW - Inspection KW - Image resolution PY - 2021 DO - https://doi.org/10.1117/12.2603838 VL - 11914 SP - 124 EP - 131 PB - International Society for Optics and Photonics. SPIE AN - OPUS4-53745 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Van Den Bossche, T. A1 - Arntzen, M. O. A1 - Becher, D. A1 - Benndorf, D. A1 - Eijsink, V. G. H. A1 - Henry, C. A1 - Jagtap, P. D. A1 - Jehmlich, N. A1 - Juste, C. A1 - Kunath, B. J. A1 - Mesuere, B. A1 - Muth, Thilo A1 - Pope, P. B. A1 - Seifert, J. A1 - Tanca, A. A1 - Uzzau, S. A1 - Wilmes, P. A1 - Hettich, R. L. A1 - Armengaud, J. T1 - The Metaproteomics Initiative: a coordinated approach for propelling the functional characterization of microbiomes N2 - Through connecting genomic and metabolic information, metaproteomics is an essential approach for understanding how microbiomes function in space and time. The international metaproteomics community is delighted to announce the launch of the Metaproteomics Initiative (www.metaproteomics.org), the goal of which is to promote dissemination of metaproteomics fundamentals, advancements, and applications through collaborative networking in microbiome research. The Initiative aims to be the central information hub and open meeting place where newcomers and experts interact to communicate, standardize, and accelerate experimental and bioinformatic methodologies in this feld. We invite the entire microbiome community to join and discuss potential synergies at the interfaces with other disciplines, and to collectively promote innovative approaches to gain deeper insights into microbiome functions and dynamics. KW - Microbiome KW - Metaproteomics KW - Networking KW - Meta-Omics KW - Interactions KW - Education PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542290 DO - https://doi.org/10.1186/s40168-021-01176-w VL - 9 IS - 1 SP - 243 PB - BMC AN - OPUS4-54229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ecke, Alexander A1 - Westphalen, Tanja A1 - Hornung, J. A1 - Voetz, M. A1 - Schneider, Rudolf T1 - A rapid magnetic bead-based immunoassay for sensitive determination of diclofenac N2 - Increasing contamination of environmental waters with pharmaceuticals represents an emerging threat for the drinking water quality and safety. In this regard, fast and reliable analytical methods are required to allow quick countermeasures in case of contamination. Here, we report the development of a magnetic bead-based immunoassay (MBBA) for the fast and cost-effective determination of the analgesic diclofenac (DCF) in water samples, based on diclofenac-coupled magnetic beads and a robust monoclonal anti-DCF antibody. A novel synthetic strategy for preparation of the beads resulted in an assay that enabled for the determination of diclofenac with a significantly lower limit of detection (400 ng/L) than the respective enzyme-linked immunosorbent assay (ELISA). With shorter incubation times and only one manual washing step required, the assay demands for remarkably shorter time to result (< 45 min) and less equipment than ELISA. Evaluation of assay precision and accuracy with a series of spiked water samples yielded results with low to moderate intra- and inter-assay variations and in good agreement with LC–MS/MS reference analysis. The assay principle can be transferred to other, e.g., microfluidic, formats, as well as applied to other analytes and may replace ELISA as the standard immunochemical method. KW - Immunoassay KW - Magnetic beads KW - Diclofenac KW - Water analysis KW - LC-MS/MS PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542346 DO - https://doi.org/10.1007/s00216-021-03778-7 SN - 1618-2650 VL - 414 SP - 1563 EP - 1573 PB - Springer CY - Heidelberg AN - OPUS4-54234 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gaal, Mate T1 - Sound field measurements on thermoacoustic air-coupled transducers N2 - There are many different methods to characterize air-coupled ultrasonic transducers for non-destructive testing. Data sheets of various manufacturers contain information about some parameters important for the performance of transducers, but this information is not standardized, so that a comparison between probes of different manufacturers is difficult. Therefore, the German Society for Non-Destructive Testing (DGZfP) is working on a guideline to characterization of air-coupled probes. One of the topics in this guideline is the application of thermoacoustic transducers for the characterization of receivers and another topic is the application of microphones for the characterization of transmitters. In this presentation we compare various characterization methods with the particular focus on the characterization of thermoacoustic transducers using an optical microphone. Both thermoacoustic transmitters and optical microphones have a very large bandwidth compared to conventional air-coupled transducers, but their spectrum is not entirely linear, which needs to be taken into account if they are applied as reference transducers. T2 - JSNDI online workshop “Emerging Technologies of Advanced Ultrasonic Measurement” CY - Online meeting DA - 14.12.2021 KW - Air-coupled ultrasound KW - Transducer KW - Sound field PY - 2021 AN - OPUS4-54195 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfennig, Anja T1 - Improving Learning Outcome for GSL (German as a Second Language) Students in a Blended Learning Cumulative Assessment Material Science Course N2 - First year students especially with migration background and language deficiencies rate material science in mechanical engineering as one of the fundamental courses with high work load and necessity of language skills due to the descriptive nature of the course. Therefore a blended learning course structure using based on inverted classroom teaching scenarios was established. Heart of the self-study period are visualizing peer-to-peer lecture films supported by micro-lectures along with various online teaching materials. Although students with migration background generally scored lower in tests due to the lack of language skills improved learning outcomes are demonstrated in high quality class discussions and in overall understanding. This paper introduces the learning structure and graded activities, evaluates the course and compares results of native German-speaking students to those of students with migration background. KW - Portfolio KW - Diversity KW - Blended learning KW - Inverted classroom KW - Lecture films PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-541557 DO - https://doi.org/10.17706/ijeeee.2021.11.3.93-100 SN - 2010-3654 VL - 11 IS - 3 SP - 93 EP - 100 AN - OPUS4-54155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cakir, Cafer Tufan T1 - Unravelling the depths of complex alloys with grazing exit XANES N2 - High entropy alloys (HEAs) are considered as a new class of alloys containing at least 5 elements with concentrations between 5 and 35 atomic percent. There has been a growing interest in HEAs in the material research field in recent years. Due to their adjustable composition, which enables the modifications of mechanical properties (such as hardness, strength and ductility etc) and their stability at high temperatures, HEAs have been the focus of various studies. Especially the corrosion behavior of HEAs has been a wide research interest. Since the grazing exit X-ray fluorescence (GEXRF) offers a non-destructive way to collect notable information regarding the high temperature oxidation, we consider it as a useful method to investigate how HEAs behave in corrosive environments. The main idea of grazing geometry is to enhance the fluorescence signal of the surface. This enables highly sensitive surface analyses of thin protective film on surface in sub-micrometer scale. Position-sensitive area detectors provide information regarding the signal emitted from the sample as a function of emission angle and thus allow depth-sensitive analysis. Furthermore, the data collected from samples of an incidence energy which lays within a specific energy range provides XANES data to determine oxidation states. Moreover, since GEXRF profiles can also be simulated through physical models (Urbach 1999), they enable us to determine the layer thickness of a given sample in a non-destructive way. In this contribution, we present the preliminary results of a conceptual study regarding layer properties of CrCoNi medium entropy alloy. The successful implementation of such methodological concept will pave the way for the investigation of more complex alloys with multiple layers, which is planned for the later phases of the project. T2 - Denver X-Ray Conference DXC 2021 CY - Online meeting DA - 02.08.2021 KW - GEXRF KW - High entropy alloys KW - XANES KW - Grazing exit KW - XAS PY - 2021 AN - OPUS4-54027 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cakir, Cafer Tufan T1 - Unrevealing the depths of compositionally complex alloys with grazing exit XANES N2 - High entropy alloys (HEAs) are considered as a new class of alloys containing at least 5 elements with concentrations between 5 and 35 atomic percent. There has been a growing interest in HEAs in the material research field in recent years. Due to their adjustable composition, which enables the modifications of mechanical properties (such as hardness, strength and ductility etc) and their stability at high temperatures, HEAs have been the focus of various studies. Especially the corrosion behavior of HEAs has been a wide research interest. Since the grazing exit X-ray fluorescence (GEXRF) offers a non-destructive way to collect notable information regarding the high temperature oxidation, we consider it as a useful method to investigate how HEAs behave in corrosive environments. The main idea of grazing geometry is to enhance the fluorescence signal of the surface. This enables highly sensitive surface analyses of thin protective film on surface in sub-micrometer scale. Position-sensitive area detectors provide information regarding the signal emitted from the sample as a function of emission angle and thus allow depth-sensitive analysis. Furthermore, the data collected from samples of an incidence energy which lays within a specific energy range provides XANES data to determine oxidation states. Moreover, since GEXRF profiles can also be simulated through physical models (Urbach 1999), they enable us to determine the layer thickness of a given sample in a non-destructive way. In this contribution, we present the preliminary results of a conceptual study regarding layer properties of CrCoNi medium entropy alloy. The successful implementation of such methodological concept will pave the way for the investigation of more complex alloys with multiple layers, which is planned for the later phases of the project. T2 - XAFS 2021, The 18th International XAFS Conference CY - Online meeting DA - 02.08.2021 KW - GEXRF KW - High entropy alloys KW - XANES KW - Grazing exit KW - XAS PY - 2021 AN - OPUS4-54028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schnur, C. A1 - Moll, J. A1 - Lugovtsova, Yevgeniya A1 - Schütze, A. A1 - Schneider, T. T1 - Explainable machine learning for damage detection - In carbon fiber composite plates under varying temperature conditions N2 - Understanding on how a machine learning model interprets data is a crucial step to verify its reliability and avoid overfitting. While the focus of the scientific community is nowadays orientated towards deep learning approaches, which are considered as black box approaches, this work presents a toolbox that is based on complementary methods of feature extraction and selection, where the classification decisions of the model are transparent and can be physically interpreted. On the example of guided wave benchmark data from the open guided waves platform, where delamination defects were simulated at multiple positions on a carbon fiber reinforced plastic plate under varying temperature conditions, the authors could identify suitable frequencies for further investigations and experiments. Furthermore, the authors presented a realistic validation scenario which ensures that the machine learning model learns global damage characteristics rather than position specific characteristics. T2 - 48th Annual Review of Progress in Quantitative Nondestructive Evaluation CY - Online meeting DA - 28.07.2021 KW - Explainable machine learning KW - Guided waves KW - Damage detection KW - Structural health monitoring KW - Composite structures PY - 2021 SN - 978-0-7918-8552-9 DO - https://doi.org/10.1115/QNDE2021-75215 SP - 1 EP - 6 PB - American Society of Mechanical Engineers (ASME) CY - New York, NY AN - OPUS4-54219 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Tchipilov, Teodor A1 - Raysyan, Anna A1 - Weller, Michael G. T1 - Methods for the quantification of particle-bound protein – Application to reagents for lateral-flow immunoassays (LFIA) N2 - Protein immobilization for the functionalization of particles is used in various applications, including biosensors, lateral-flow immunoassays (LFIA), bead-based assays, and others. Common methods for the quantification of bound protein are measuring protein in the supernatant before and after coating and calculating the difference. This popular approach has the potential for a significant overestimation of the amount of immobilized protein since layers not directly bound to the surface (soft protein corona) are usually lost during washing and handling. Only the layer directly bound to the surface (hard corona) can be used in subsequent assays. A simplified amino acid analysis method based on acidic hydrolysis and RP-HPLC-FLD of tyrosine and phenylalanine (aromatic amino acid analysis, AAAA) is proposed to directly quantify protein bound to the surface of gold nano- and latex microparticles. The results are compared with indirect methods such as colorimetric protein assays, such as Bradford, bicinchoninic acid (BCA), as well as AAAA of the supernatant. For both particle types, these indirect quantification techniques show a protein overestimation of up to 1700% compared to the direct AAAA measurements. In addition, protein coating on latex particles was performed both passively through adsorption and covalently through EDC/sulfo-NHS chemistry. Our results showed no difference between the immobilization methodologies. This finding suggests that usual protein determination methods are no unambiguous proof of a covalent conjugation on particles or beads. KW - Soft protein corona KW - Hard protein corona KW - Gold particles KW - Nanoparticles KW - Mikroparticles KW - Antibody KW - Bioconjugation KW - Protein quantification KW - Supernatant KW - Sodium chloride method KW - Covalent conjugation KW - Latex particles KW - Lateral flow immunoassays PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545365 DO - https://doi.org/10.20944/preprints202203.0332.v1 SP - 1 EP - 8 PB - MDPI CY - Basel AN - OPUS4-54536 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lemke, Nora A1 - El-Khatib, Ahmed H. A1 - Tchipilov, Teodor A1 - Jakubowski, N. A1 - Weller, Michael G. A1 - Vogl, Jochen T1 - Procedure providing SI‑traceable results for the calibration of protein standards by sulfur determination and its application on tau N2 - Quantitative proteomics is a growing research area and one of the most important tools in the life sciences. Well-characterized and quantified protein standards are needed to achieve accurate and reliable results. However, only a limited number of sufficiently characterized protein standards are currently available. To fill this gap, a method for traceable protein quantification using sulfur isotope dilution inductively coupled plasma mass spectrometry (ICP-MS) was developed in this study. Gel filtration and membrane filtration were tested for the separation of non-protein-bound sulfur in the protein solution. Membrane filtration demonstrated a better performance due to the lower workload and the very low sulfur blanks of 11 ng, making it well suited for high-purity proteins such as NIST SRM 927, a bovine serum albumin (BSA). The method development was accomplished with NIST SRM 927e and a commercial avidin. The quantified mass fraction of NIST SRM 927e agreed very well with the certified value and showed similar uncertainties (3.6%) as established methods while requiring less sample preparation and no species-specific standards. Finally, the developed procedure was applied to the tau protein, which is a biomarker for a group of neurodegenerative diseases denoted “tauopathies” including, e.g., Alzheimer’s disease and frontotemporal dementia. For the absolute quantification of tau in the brain of transgenic mice overexpressing human tau, a well-defined calibration standard was needed. Therefore, a pure tau solution was quantified, yielding a protein mass fraction of (0.328 ± 0.036) g/kg, which was confirmed by amino acid analysis. KW - Iinductively coupled plasma mass spectrometry KW - Isotope dilution KW - Quantitative protein analysis KW - Sulfur KW - SI traceability PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545200 DO - https://doi.org/10.1007/s00216-022-03974-z VL - 414 SP - 4441 EP - 4455 PB - Springer Verlag AN - OPUS4-54520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dariz, P. A1 - Wortmann, U. G. A1 - Vogl, Jochen A1 - Schmid, Thomas T1 - Beautiful Pietàs in South Tyrol (Northern Italy): local or imported works of art? N2 - The study, dedicated to Beautiful Pietàs conserved in South Tyrol (Northern Italy), aims to establish, for the first time, a connection between Austroalpine raw materials and the high-fired gypsum mortars constituting the Gothic figure groups in question. The origin and chronology of this stylistically and qualitatively differing ensemble have been subject of art historical debate for nearly a century. The discourse is dominated by three main hypotheses: itinerary of an Austrian artist versus itinerary of the work of art created in an artist’s workshop in Austria versus itinerary of the stylistic vocabulary via graphical or three-dimensional models. The comparison of the δ34S values and the 87Sr/86Sr ratios of the gypsum mortars and Austroalpine sulphate deposits (in a compilation of own reference samples and literature data) points to the exploitation of sediments in the Salzkammergut and possibly also in the evaporite district of the Eastern Calcareous Alps, thus evidencing the import of the sculptures and not the activities of local South Tyrolean or itinerant artists. Two geochronological units are distinguishable: The Pietà in the Church St. Martin in Göflan can be assigned to Upper Permian raw material, whereas the metrologically consistent sculptures in the Church of Our Lady of the Benedictine Abbey Marienberg and in the Chapel St. Ann in Mölten correlate with deposits of the Early Triassic (or the Lower-Middle Triassic transition). The medieval gypsum mortars also differ in their mineralogical characteristics, i.e. in their geologically related minor components, as in the first case, characterised by a significant proportion of primary anhydrite, natural carbonate impurities mainly consist of calcite (partly converted to lime-lump-like aggregates), whereas in the second group dolomite (or rather its hydration products after pyrometamorphic decomposition) predominates, accompanied by celestine, quartz and potassium feldspar. The Pietà in the Cathedral Maria Himmelfahrt in Bozen turned out to be made of Breitenbrunn calcareous sandstone (Leitha Mountains, Burgenland, Austria), which is why the sample is not considered in the geochemical analysis. KW - High-fired gypsum mortar KW - Sulphur isotope KW - Strontium isotope KW - Polarised light microscopy KW - Raman microspectroscopy PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545610 DO - https://doi.org/10.1186/s40494-022-00678-6 SN - 2050-7445 VL - 10 IS - 1 SP - 1 EP - 17 PB - Springer Nature AN - OPUS4-54561 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kudela, P. A1 - Radzienski, M. A1 - Moix-Bonet, M. A1 - Willberg, C. A1 - Lugovtsova, Yevgeniya A1 - Bulling, Jannis A1 - Tschöke, K. A1 - Moll, J. T1 - Dataset on full ultrasonic guided wavefield measurements of a CFRP plate with fully bonded and partially debonded omega stringer N2 - The fourth dataset dedicated to the Open Guided Waves platform presented in this work aims at a carbon fiber composite plate with an additional omega stringer at constant temperature conditions. The dataset provides full ultrasonic guided wavefields. A chirp signal in the frequency range 20-500 kHz and Hann windowed tone-burst signal with 5 cycles and carrier frequencies of 16.5 kHz, 50 kHz, 100 kHz, 200 kHz and 300kHz are used to excite the wave. The piezoceramic actuator used for this purpose is attached to the center of the stringer side surface of the core plate. Three scenarios are provided with this setup: (1) wavefield measurements without damage, (2) wavefield measurements with a local stringer debond and (3) wavefield measurements with a large stringer debond. The defects were caused by impacts performed from the backside of the plate. As result, the stringer feet debonds locally which was verified with conventional ultrasound measurements. The dataset can be used for benchmarking purposes of various signal processing methods for damage imaging. The detailed description of the dataset is published in Data in Brief Journal. KW - Open data KW - Ultrasonic guided waves KW - Experimental data PY - 2021 DO - https://doi.org/10.5281/zenodo.5105861 PB - Zenodo CY - Geneva AN - OPUS4-54504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kudela, P. A1 - Radzienski, M. A1 - Moix-Bonet, M. A1 - Willberg, C. A1 - Lugovtsova, Yevgeniya A1 - Bulling, Jannis A1 - Tschöke, K. A1 - Moll, J. T1 - Dataset on full ultrasonic guided wavefield measurements of a CFRP plate with fully bonded and partially debonded omega stringer N2 - The fourth dataset dedicated to the Open Guided Waves platform presented in this work aims at a carbon fiber composite plate with an additional omega stringer at constant temperature conditions. The dataset provides full ultrasonic guided wavefields. Two types of signals were used for guided wave excitation, namely chirp signal and tone-burst signal. The chirp signal had a frequency range of 20-500kHz. The tone-burst signals had a form of sine modulated by Hann window with 5 cycles and carrier frequencies 16.5kHz, 50kHz, 100kHz, 200kHz, 300kHz. The piezoceramic actuator used for this purpose was attached to the center of the stringer side surface of the core plate. Three scenarios are provided with this setup: (1) wavefield measurements without damage, (2) wavefield measurements with a local stringer debond and (3) wavefield measurements with a large stringer debond. The defects were caused by impacts performed from the backside of the plate. As result, the stringer feet debonds locally which was verified with conventional ultrasound measurements. KW - Lamb waves KW - Composite panel KW - Impact damage KW - Damage detection KW - Scanning laser Doppler vibrometry KW - Structural health monitoring KW - Non-destructive evaluation KW - Open data PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545242 DO - https://doi.org/10.1016/j.dib.2022.108078 SN - 2352-3409 VL - 42 SP - 1 EP - 13 PB - Elsevier CY - Amsterdam AN - OPUS4-54524 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fiedler, Saskia T1 - Cathodoluminescence Spectroscopy of Silicon Nanoparticles N2 - The fabrication of nanostructures with ever-decreasing sizes has increased the demand of suitable characterization methods which allow to determine their shape and size at the true nanoscale, and similarly important, enable the investigation of their optical properties beyond the diffraction limit. Due to its high spectral and spatial resolution down to the (sub-) nanometer range, electron beam-based techniques, namely cathodoluminescence (CL) has become a powerful characterization tool, particularly to study plasmonic and dielectric nanostructures. However, the interpretation of the resulting spectral CL maps is not always unambiguously straightforward. In this work, Mie resonances in single Si nanospheres of different sizes have been systematically studied, using experimental CL spectroscopy and an analytical CL model. For smaller spheres (r ~ 75 nm), the eigenmodes can be unequivocally identified, with relative changes in intensity of the electric and magnetic dipole depending on the electron beam position within the sphere. However, in larger spheres (r ~ 105 nm), the modal assignment becomes increasingly difficult due to a larger number of Mie modes in the visible spectral range. Additionally, penetrating electron beams generate two radiating dipoles at the two Si interfaces – due to the electron and its image charge collapsing at those interfaces – which can, depending on the electron beam’s velocity and its path length inside the particle, produce distinct resonances or dips (constructive or destructive interference of those two radiative dipoles). It is demonstrated that superimposed on the eigenmodes of the studied nanospheres, these resonances can distort the recorded spectrum and lead to potentially erroneous assignment of modal characters to the spectral features. An intuitive analogy is developed to unambiguously distinguish those resonance induced by transition radiation from the nanoparticle-specific Mie resonances. T2 - Optoelectronic Processes at Nanostructured Interfaces 2022 CY - Bad Honnef, Germany DA - 21.03.2022 KW - Cathodoluminescence KW - Silicon nanoparticles KW - Mie resonances PY - 2022 AN - OPUS4-54526 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Doolette, A. A1 - Huang, J. T1 - Combining diffusive gradients in thin-films (DGT) and 31P NMR spectroscopy to determine phosphorus species in soil N2 - The diffusive gradients in thin-films (DGT) technique shows in many publications a superior correlation to the amount of plant-available phosphorus (P) in soil. However, this technique cannot give information on the plant-available P species in soil. Therefore, we combined DGT with solution 31P nuclear magnetic resonance (NMR) spectroscopy. This was achieved by using a modified DGT device in which the diffusive layer had a larger pore size, the binding layer incorporated an adsorption material with a higher capacity, and the device had a larger exposure area. The spectroscopic investigation was undertaken after elution of the deployed DGT binding layer in a NaOH solution. Adsorption tests using solutions of known organic P compounds showed that a sufficient amount of these compounds could be adsorbed on the binding layer in order for them to be analyzed by solution 31P NMR spectroscopy. Furthermore, various intermediates of the hydrolysis of trimetaphosphate in soil could be also analyzed over time. KW - Phosphorus KW - Diffusive gradients in thin-films (DGT) KW - Passive sampling KW - fertilizer PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545759 DO - https://doi.org/10.1002/ael2.20068 VL - 7 IS - 1 SP - e20068 PB - Wiley online library AN - OPUS4-54575 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gornushkin, Igor B. T1 - Modeling Equilibrium Chemistry in Laser Induced Plasmas and Plasma Chemical Reactors N2 - A brief introduction will be given on modeling chemical reactions in laser induced plasmas using stoichiometric and non-stoichiometric approaches. Several applications will be considered, which can benefit from such modeling. Those include plasma enhanced chemical vapor deposition (PECVD), surface modification and surface coating, and molecular analysis by LIBS. Each application will be illustrated by simulations of relevant chemical systems. For PECVD, chemical systems are BCl3/H2/Ar, BF3/H2/Ar, BCl3/BF3, Mo/BF3/H2; for surface modification/coating it is Ti/air; for molecular LIBS they are CaCO3/Ar, Ca(OH)2/Ar, and CaCl2/Ar. Advantages and shortcomings of equilibrium chemical hydrodynamic models of laser induced plasmas will be discussed. T2 - 1st NIP Conference National Institute of Physics (IKF), the Albanian Academy of Sciences CY - Online meeting DA - 10.02.2022 KW - Laser ablation KW - Laser induced plasma deposition KW - Surface coating KW - Titanium dioxide KW - Emission spectroscopy KW - Hydrodynamic model KW - Plasma chemistry PY - 2022 AN - OPUS4-54328 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gornushkin, Igor B. T1 - Plasma Fundamentals and Diagnostics N2 - This course will provide an introduction to plasma diagnostic techniques. The major focus of the course will be on the discussions of the practical procedures as well as the underlying physical principles for the measurements of plasma fundamental characteristics (e.g., temperatures and electron number density). Particular emphasis will be placed on laser induced plasma–atomic emission spectrometry, but other analytical plasmas will also be used as examples when appropriate. Selected examples on how one can manipulate the operating conditions of the plasma source, based on the results of plasma diagnostic measurements, to improve its performance used for spectrochemical analysis will also be covered. Topics to be covered include thermal equilibrium, line profiles, temperatures, electron densities, excitation processes, temporal and spatial resolution. T2 - 2022 Winter Conference on Plasma Spectrochemistry CY - Tucson, Arizona, USA DA - 17.01.2022 KW - Thermal equilibrium KW - Excitation processes KW - Electron number density KW - Temperatures KW - Spatial information KW - Emission line profiles PY - 2022 AN - OPUS4-54288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tang, Chi-Long A1 - Wilke, Olaf A1 - Seeger, Stefan A1 - Kalus, Sabine A1 - Erdmann, Kerstin T1 - Chemical characterization of ultrafine particles released from 3D printers N2 - Previous studies have shown that desktop 3D printers (Fused Filament Fabrication) emit high numbers of particulate matter, mainly as ultrafine particles (UFP, particle diameter less than 100 nm). However, the chemical composition of emitted particles has been less extensively investigated. In this study, we therefore focused on the chemical composition of particles emitted from 3D printing. The measurements were conducted in a 1 m³ emission test chamber. Emitted particles were sampled by a 13-stage low-pressure cascade impactor onto aluminum foils and then analyzed by TD-GC/MS to identify their organic compounds. Nine commercial filaments made from basic polymers such as Acrylonitrile Butadiene Styrene (ABS), Acrylonitrile Styrene Acrylate (ASA), Polycarbonate (PC), Poly(methyl methacrylate) (PMMA), Nylon, High Performance Polystyrene (HIPS) and a copper-filled Polylactide (PLA) were investigated. The results show that the organic components of the particles are primarily plastic additives such as plasticizer, antioxidant agents, lubricants, UV-absorbers and UV-stabilizers from the filaments. T2 - 17th International Conference Healthy Buildings Europe 2021 CY - Online Meeting DA - 21.06.2021 KW - Chemical characterization KW - FFF-3D-Printer KW - UFP KW - Chamber measurement PY - 2021 SP - 251 EP - 252 AN - OPUS4-54255 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Held, Mathias T1 - Inverse determination of elastic material parameters from the propagation behavior of ultrasonic waves using convolutional neuronal networks N2 - Um aus messtechnisch ermittelten Dispersionsabbildungen geführter Ultraschallwellen Rückschlüsse auf die Materialparameter zu ziehen, werden in der aktuellen Forschung verschiedene inverse Methoden diskutiert. Maschinelles Lernen und insbesondere Convolutional-Neural-Networks (CNNs) stellen eine Möglichkeit der automatisierten inversen Modellierung und Evaluierung von Bilddaten dar. In diesem Vortrag wird anhand synthetischer Daten gezeigt, wie das Ausbreitungsverhalten von geführten Ultraschallwellen unter Verwendung von CNNs genutzt werden kann, um die isotropen elastischen Konstanten einer plattenförmigen Struktur zu bestimmen. T2 - Doktorandentreffen 2021 CY - Petershagen/Eggersdorf, Germany DA - 25.10.2021 KW - Convolutional Neuronal Networks KW - Inverse Probleme KW - Materialcharakterisierung KW - Maschine learning KW - Guided waves KW - Lamb Wellen PY - 2021 AN - OPUS4-54264 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Casali, C. A1 - Feiler, Torvid A1 - Heilmann, Maria A1 - Braga, D. A1 - Emmerling, Franziska A1 - Grepioni, F. T1 - Too much water? Not enough? In situ monitoring of the mechanochemical reaction of copper salts with dicyandiamide N2 - n situ monitoring of mechanochemical reactions between dicyandiamide (DCD) and CuX2 salts (X = Cl−, NO3−), for the preparation of compounds of agrochemical interest, showed the appearance of a number of phases. It is demonstrated that milling conditions, such as the amount of water added in wet grinding and/or the milling frequency, may affect the course of the mechanochemical reactions, and drive the reaction towards the formation of different products. It has been possible to discover by in situ monitored experiments two novel crystalline forms, namely the neutral complexes [Cu(DCD)2(OH2)2(NO3)2] (2) and [Cu(DCD)2(OH2)Cl2]·H2O (4), in addition to the previously known molecular salt [Cu(DCD)2(OH2)2][NO3]2·2H2O (1, DIVWAG) and neutral complex [Cu(DCD)2(OH2)Cl2] (3, AQCYCU), for which no synthesis conditions were available. Compounds 2 and 4 were fully characterized via a combination of solid-state techniques, including X-ray diffraction, Raman spectroscopy and TGA. KW - Mechanochemistry KW - In situ PY - 2022 DO - https://doi.org/10.1039/d1ce01670a VL - 24 IS - 6 SP - 1292 EP - 1298 PB - RSC AN - OPUS4-54344 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Fabian A1 - Gehrenkemper, Lennart A1 - von der Au, Marcus A1 - Wittwer, Phillip A1 - Roesch, Philipp A1 - Pfeifer, Jens A1 - Cossmer, Antje A1 - Meermann, Björn T1 - A fast and simple PFAS extraction method utilizing HR–CS–GFMAS for soil samples N2 - Here, we describe an optimized fast and simple extraction method for the determination of per- and polyfluorinated alkyl substances (PFASs) in soils utilizing high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR–CS–GFMAS). To omit the bias of the solid phase extraction (SPE) step commonly used during the analysis of extractable organically bound fluorine (EOF) we optimized a fast and simple SPE-free extraction method. The developed extraction method consists of a liquid-solid extraction using acidified methanol without any additional SPE. Four extraction steps were representative to determine a high proportion of the EOF (>80% of eight extractions). Comparison of the optimized method with and without an additional SPE clean-up step revealed a drastic underestimation of EOF concentrations using SPE. Differences of up to 94% were observed which were not explainable by coextracted inorganic fluoride. Therefore, not only a more accurate but also a more economic as well as ecologic method (bypassing of unnecessary SPE) was developed. The procedural limit of quantification (LOQ) of the developed method was 10.30 μg/kg which was sufficient for quantifying EOF concentrations in all tested samples. For future PFAS monitoring and potential regulative decisions the herein presented optimized extraction method can offer a valuable contribution. KW - Per- and polyfluorinated alkly substances (PFASs) KW - High resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) KW - Soils KW - Solid phase extraction (SPE) KW - Extractable organically bound fluorine (EOF) KW - Solid-liquid extraction PY - 2022 DO - https://doi.org/10.1016/j.chemosphere.2022.133922 VL - 295 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-54359 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Frisch, M. A1 - Raza, M. H. A1 - Ye, M.-Y. A1 - Sachse, René A1 - Paul, B. A1 - Gunder, R. A1 - Pinna, N. A1 - Kraehnert, R. T1 - ALD-coated mesoporous iridium-titanium mixed oxides: Maximizing iridium utilization for an outstanding OER performance N2 - With the increasing production of renewable energy and concomitant depletion of fossil resources, the demand for efficient water splitting electrocatalysts continues to grow. Iridium (Ir) and iridium oxides (IrOₓ) are currently the most promising candidates for an efficient oxygen evolution reaction (OER) in acidic medium, which remains the bottleneck in water electrolysis. Yet, the extremely high costs for Ir hamper a widespread production of hydrogen (H₂) on an industrial scale. Herein, the authors report a concept for the synthesis of electrode coatings with template-controlled mesoporosity surface-modified with highly active Ir species. The improved utilization of noble metal species relies on the synthesis of soft-templated metal oxide supports and a subsequent shape-conformal deposition of Ir species via atomic layer deposition (ALD) at two different reaction temperatures. The study reveals that a minimum Ir content in the mesoporous titania-based support is mandatory to provide a sufficient electrical bulk conductivity. After ALD, a significantly enhanced OER activity results in dependency of the ALD cycle number and temperature. The most active developed electrocatalyst film achieves an outstanding mass-specific activity of 2622 mA mg(Ir)⁻¹ at 1.60 V(RHE) in a rotating-disc electrode (RDE) setup at 25 °C using 0.5 m H₂SO₄ as a supporting electrolyte. KW - Acidic oxygen evolution reaction KW - Atomic layer deposition KW - Electrocatalysis KW - Iridium oxide KW - Soft-templated mesoporous films PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542651 DO - https://doi.org/10.1002/admi.202102035 SN - 2196-7350 SP - 1 EP - 11 PB - Wiley-VCH CY - Weinheim AN - OPUS4-54265 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hassenstein, Christian T1 - Adaptive TFM approach for turbine blade testing in an NDE 4.0 environment N2 - Turbine blades for gas turbines are exposed to extreme working conditions in a demanding environment. In-service inspection, maintenance and refurbishment of the heavily stressed parts is necessary to ensure both safety and efficiency, e.g. based on immersion ultrasound testing (UT). In the course of NDE 4.0, the European project MRO 2.0 aims to innovate the maintenance, repair and overhaul of turbine blades by linking these with modern digital methods. For this, the goal of this project is to go beyond conventional automated and manual UT testing techniques. The aim is to measure the actual geometry and wall thickness of the complex shaped parts by applying an adaptive TFM that takes into account the refraction of the ultrasonic waves at the transition from the coupling material (water) to the inspected part (steel). In this setup the phased array probe is held by a robotic arm that allows the part to be scanned while remaining mainly perpendicular to the inspected surface. In this way, even complex geometries can be inspected and a 3D model of the actual condition of the part can be created. The laboratory setup is equipped with a Vantage 64 phased array instrument from Verasonics Inc. and an industrial robot from ABB. A 64 element linear array probe operating at 10 MHz is attached to the robot. The focus is on optimizing resolution, reliability and inspection speed, as the reconstructed model will be fed to the digital twin at a later stage of the project and used for targeted repairs. In addition to enhancing the reconstruction algorithms, required probe geometry and the parameters needed to inspect turbine blades with partially thin walls and anisotropic materials will also be investigated. This talk will describe the 3-year project and present the results of the first year. The main focus will be on the development of the reconstruction algorithms used and the experimental setup. T2 - 48th Annual Review of Progress in Quantitative Nondestructive Evaluation (QNDE 2021) CY - Online meeting DA - 28.07.2021 KW - Utrasound testing KW - Turbine blade KW - Maintenance KW - Phased array KW - Automation PY - 2021 AN - OPUS4-54313 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gornushkin, Igor B. T1 - Deposition of Titanium Oxides by Nanosecond Laser Ablation: Simulation and Experiment N2 - Surface modification of titanium by laser ablation is investigated theoretically and experimentally. The modification consists in texturing the surface and redeposition of chemically transformed material from the ablation plasma. The redeposition is driven by the hydrodynamic flow in the plasma. Such surface modification improves the biocompatibility of titanium implants. T2 - 2022 Winter Conference on Plasma Spectrochemistry CY - Tucson, Arizona, USA DA - 17.01.2022 KW - Laser ablation KW - Laser induced plasma deposition KW - Surface coating KW - Titanium dioxide KW - Emission spectroscopy KW - Hydrodynamic model KW - Plasma chemistry PY - 2022 AN - OPUS4-54289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kornev, R. A. A1 - Sennikov, P. G. A1 - Gornushkin, Igor B. A1 - Ermakov, A. A. A1 - Shkrunin, V. E. A1 - Polykov, V. S. A1 - Kornev, A. R. A1 - Kornev, K. D. T1 - Laser induced dielectric breakdown as a novel method for the synthesis of molybdenum boride N2 - Laser induced dielectric breakdown (LIDB) on a surface of solid Mo in H2/BF3 atmosphere at 30-760 Torr and in a gaseous mixture MoF6/H2/BF3 + at 760 Torr pressure is tested for synthesis and deposition of superhard molybdenum borides that are needed in many areas of industry and technology. The emission spectra of the plasma and the dynamics of the gas discharge near the substrate are investigated. A comparative analysis of the gas mixture before and after exposure to LIDB plasma is carried out using IR spectroscopy. The conditions for the formation of molybdenum borides are determined. A thermodynamic analysis of the MoF6/H2/BF3 and Mo/H2/BF3 systems is carried out to determine the temperature range for the formation of molybdenum borides and establish the main chemical reactions responsible for their formation. Deposits containing MoB and MoB2 phases are obtained. For the mixture MoF6/H2/BF3, the deposit exhibits an amorphous layered structure, which contains 19.15 wt% F, 30.45% O, and 0.8% Si. For the Mo/H2/BF3 system at the pressures 30 and 160 Torr, nanopowder of molybdenum boride is produced with a characteristic grain size of 100 nm. At pressures above 160 Torr, Mo nanopowder with a grain size <30 nm is obtained. KW - LIDB plasma KW - MoF6 KW - BF3 KW - Hydrogen reduction KW - Molybdenum boride PY - 2022 DO - https://doi.org/10.1007/s11090-021-10224-0 SN - 1572-8986 SP - 1 EP - 18 PB - Springer CY - Dordrecht AN - OPUS4-54290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska T1 - In situ investigations of mechanochemical processes N2 - Overview of the present BAM activities in the field of in situ analytics of mechanochemical processes. Recent results for the synthesis of metal organic frameworks and cocrystals are presented. T2 - HZB Seminar CY - Online meeting DA - 21.01.2022 KW - Mechanochemistry KW - In situ real-time monitoring PY - 2022 AN - OPUS4-54296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kruschwitz, Sabine A1 - Oesch, T. A1 - Mielentz, Frank A1 - Meinel, Dietmar A1 - Spyridis, P. T1 - Non-Destructive Multi-Method Assessment of Steel Fiber Orientation in Concrete N2 - Integration of fiber reinforcement in high-performance cementitious materials has become widely applied in many fields of construction. One of the most investigated advantages of steel Fiber reinforced concrete (SFRC) is the deceleration of crack growth and hence its improved sustainability. Additional benefits are associated with its structural properties, as fibers can significantly increase the ductility and the tensile strength of concrete. In some applications it is even possible to entirely replace the conventional reinforcement, leading to significant logistical and environmental benefits. Fiber reinforcement can, however, have critical disadvantages and even hinder the Performance of concrete, since it can induce an anisotropic material behavior of the mixture if the fibers are not appropriately oriented. For a safe use of SFRC in the future, reliable non-destructive testing (NDT) methods need to be identified to assess the fibers’ orientation in hardened concrete. In this study, ultrasonic material testing, electrical impedance testing, and X-ray computed tomography have been investigated for this purpose using specially produced samples with biased or random Fiber orientations. We demonstrate the capabilities of each of these NDT techniques for fiber orientation measurements and draw conclusions based on these results about the most promising areas for future research and development. KW - Spectral induced polarization KW - Steel fiber reiniforced concrete KW - Fiber orientation KW - Non-destructive testing KW - Micro-computed tomography KW - Ultrasound PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543520 DO - https://doi.org/10.3390/app12020697 VL - 12 IS - 2 SP - 1 EP - 14 PB - MDPI CY - Basel Switzerland AN - OPUS4-54352 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lakshmipathi, M. A1 - Tothadi, S. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Ghosh, S. T1 - Different mechanical responses of dimorphic forms of Anthracene Schiffbase crystal N2 - We obtained concomitant dimorphic forms of Anthracene Schiffbase (N-(anthracen-9-yl methylene)-2,5- dichloroaniline) from hexane solvent. Two polymorphs can be differentiated by their morphology and mechanical properties. One form is long acicular type and elastically bendable while another form is block shaped and brittle in nature. Mechanical property is attributed to underlying crystal packing. Hirsh- feld analysis and energy framework calculations were done to corroborate structure-property correlation of two forms. KW - Elasticity KW - Mechanical properties KW - Anthracene schiff base KW - Dimorphs PY - 2021 DO - https://doi.org/10.1016/j.molstruc.2021.132182 VL - 1252 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-54356 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Müller, Anja T1 - Determination of the actual morphology of core-shell nanoparticles by advanced X-ray analytical techniques: A necessity for targeted and safe nanotechnology N2 - Even though we often do not knowingly recognize them, nanoparticles are present these days in most areas of our daily life, including food and its packaging, medicine, pharmaceuticals, cosmetics, pigments as well as electronic products, such as computer screens. The majority of these particles exhibits a core-shell morphology either intendedly or unintendedly. For the purpose of practicability, this core-shell nanoparticle (CSNP) morphology is often assumed to be ideal, namely a spherical core fully encapsulated by a shell of homogeneous thickness with a sharp interface between core and shell material. It is furthermore widely presumed that all nanoparticles in the sample possess the same shell thickness. As a matter of fact, most real CSNPs deviate in several ways from this ideal model with quite often severe impact on how efficiently they perform in a specific application. The topic of this cumulative PhD thesis is the accurate characterization of the actual morphology of CSNPs by advanced X-ray analytical techniques, namely X-ray photoelectron spectroscopy (XPS) and scanning transmission X-ray microscopy (STXM). A special focus is on CSNPs which deviate from an ideal core-shell morphology. In the paper from 2019 nanoparticle shell thicknesses are extracted from the elastic-peak intensities in an XPS spectrum based on an ideal particle morphology. This happens for a series of CSNP samples comprising a poly(tetrafluoroethylene) (PTFE) core and either a poly(methyl methacrylate) (PMMA) or polystyrene (PS) shell. The same paper as well as the paper from 2020 demonstrate for the first time, that the analysis of the inelastic background in an XPS spectrum of CSNPs can identify and quantify the heterogeneity of the shell and the incomplete encapsulation of the core. The result from an XPS experiment is always an average across a large nanoparticle ensemble. Deviations from an ideal morphology within a single particle of the sample cannot be assessed separately. As opposed to that, a spatial resolution of 35 nm enables STXM to visualize the interior of single CSNPs which exhibit a sufficient X-ray absorption contrast between core and shell material. In the paper from 2018 a STXM analysis is demonstrated based on the example of the PTFE-PS CSNP samples already mentioned in the previous paragraph. In the publication from 2021 (Ca/Sr)F₂ core-shell like nanoparticle ensembles for the practical use in, among others, antireflective coatings are investigated. These nanoparticles do not possess a sharp interface between core and shell material, which is why a shell thickness determination as described in the second paragraph is inappropriate. Instead, in-depth profiles of the chemical composition are obtained by XPS experiments based on synchrotron radiation with variable X-ray photon energy to elucidate the internal morphology of the particles. Additionally, theoretical in-depth profiles of Ca and Sr XPS peak intensities are simulated, in order to facilitate the interpretation of the experiments. Thus, an enrichment of CaF₂ at the particle surface was determined, which could hardly have been assessed by any other analytical technique. Because this kind of non-destructive depth profiling by XPS is very demanding, more than usual effort is spent on gapless documentation of the experiments to ensure full reproducibility. Due to the vast diversity of nanoparticles differing in material, composition and shape, a measurement procedure cannot unalteredly be transferred from one sample to another. Nevertheless, because the papers in this thesis present a greater depth of reporting on the experiments than comparable publications, they constitute an important guidance for other scientists on how to obtain meaningful information about CSNPs from surface analysis. N2 - Obwohl wir sie oft nicht bewusst wahrnehmen, sind Nanopartikel heutzutage in den meisten Bereichen unseres Alltags präsent, unter anderem in Lebensmitteln und ihren Verpackungen, Medizin, Medikamenten, Kosmetik, Pigmenten und in elektronischen Geräten wie Computermonitoren. Ein Großteil dieser Partikel weist, beabsichtigt oder unbeabsichtigt, eine Kern-Schale Morphologie auf. Einfachheitshalber wird diese Morphologie eines Kern-Schale-Nanopartikels (CSNP) oft als ideal angenommen, d.h. als ein sphärischer Kern, der komplett von einer Schale homogener Dicke bedeckt ist, mit einer scharfen Grenzfläche zwischen Kern- und Schalenmaterial. Außerdem wird vielfach auch davon ausgegangen, alle Partikel der Probe hätten gleiche Schalendicken. Tatsächlich weichen die meisten realen CSNPs in verschiedenster Weise von diesem Idealmodell ab, mit oft drastischen Auswirkungen darauf, wie gut sie ihre Aufgabe in einer bestimmten Anwendung erfüllen. Das Thema dieser kumulativen Doktorarbeit ist die exakte Charakterisierung der wirklichen Morphologie von CSNPs mit modernen Röntgen-basierten Methoden, konkret Röntgen-Photoelektronen-Spektroskopie (XPS) und Raster-Transmissions-Röntgen-Mikroskopie (STXM). Der Fokus liegt insbesondere auf CSNPs, die von einer idealen Kern-Schale-Morphologie abweichen. Im Artikel von 2019 werden Schalendicken von Nanopartikeln aus den elastischen Peakintensitäten im XPS-Spektrum unter Annahme einer idealen Partikelmorphologie abgeleitet. Dies geschieht für eine Reihe von CSNP-Proben, welche aus einem Polytetrafluoroethylen- (PTFE) Kern und entweder einer Polymethylmethacrylat- (PMMA) oder Polystyrol- (PS) Schale bestehen. Sowohl dieser Artikel als auch der von 2020 zeigen erstmals, dass die Auswertung des inelastischen Untergrunds eines CSNP-XPS-Spektrums in der Lage ist, die Heterogenität der Schale und die unvollständige Ummantelung des Kerns zu identifizieren und zu quantifizieren. Das Ergebnis eines XPS-Experiments ist immer ein Mittelwert über ein großes Nanopartikelensemble. Inwiefern ein einzelner Partikel innerhalb der Probe von einer idealen Morphologie abweicht, kann nicht gesondert erfasst werden. Im Gegensatz dazu kann STXM mit einer räumlichen Auflösung von 35 nm das Innere einzelner CSNPs visualisieren, sofern sie genügend Röntgenabsorptionskontrast zwischen Kern- und Schalenmaterial aufweisen. Im Artikel von 2018 wird am Beispiel der bereits im vorherigen Abschnitt genannt PTFE-PS-CSNPProben eine solche STXM-Untersuchung demonstriert. In der Veröffentlichung von 2021 werden Kern-Schale-artige (Ca/Sr)F₂-Nanopartikel für den praktischen Einsatz in unter anderem entspiegelnden Beschichtungen untersucht. Da hier keine scharfe Grenzfläche zwischen Kern- und Schalenmaterial vorliegt, ist eine Schalendickenbestimmung, wie sie im zweiten Abschnitt diskutiert wird, nicht sinnvoll. Stattdessen werden mit Hilfe von XPS, angeregt mit Synchrotronstrahlung bei variabler Röntgenphotonenenergie, Tiefenprofile der chemischen Zusammensetzung generiert, um die innere Morphologie der Partikel aufzuklären. Zusätzlich werden theoretische Tiefenprofile der Ca- und Sr-XPS-Peakintensitäten simuliert, um die Interpretation der Experimente zu erleichtern. So wurde eine CaF₂-Anreicherung an der Oberfläche der Partikel festgestellt, die kaum mit einer anderen analytischen Methode hätte entdeckt werden können. Da diese zerstörungsfreie Bestimmung von XPS-Tiefenprofilen sehr anspruchsvoll ist, wird noch mehr als üblich auf die lückenlose Dokumentation des Experiments geachtet, um vollständige Reproduzierbarkeit zu gewährleisten. Aufgrund der enormen Vielfalt an CSNPs, die sich in Material, Zusammensetzung und Form unterscheiden, kann eine Messmethode nicht völlig unverändert von einer Probe auf eine andere übertragen werden. Nichtsdestotrotz, da die als Teil dieser Doktorarbeit präsentierten Artikel eine deutlich ausführlichere Beschreibung der Experimente enthalten als vergleichbare Publikationen, stellen sie eine wichtige Anleitung für andere Wissenschaftler dafür dar, wie aussagekräftige Informationen über CSNPs durch Oberflächenanalytik erhalten werden können. KW - Core-shell nanoparticle (CSNP) KW - X-ray photoelectron spectroscopy (XPS) KW - Scanning transmission X-ray microscopy (STXM) PY - 2022 DO - https://doi.org/10.18452/24312 SP - i EP - 243 PB - Humboldt-Universität CY - Berlin AN - OPUS4-54991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gornushkin, Igor B. T1 - Optical Detection of Defects during Laser Metal Deposition N2 - Laser metal deposition is a rapidly evolving method for additive manufacturing that combines high performance and simplified production routine. Quality of production depends on an instrumental design and operational parameters, which require constant control during the process. In this work, feasibility of using optical spectroscopy as a control method is studied via modeling and experimentally. A simplified thermal model is developed based on the time-dependent diffusion-conduction heat equation and geometrical light collection into detection optics. Intense light emitted by a laser-heated spot moving across a sample surface is collected and processed to yield the temperature and other temperature-related parameters. In the presence of surface defects, the temperature field is distorted in a specific manner that depends on shape and size of the defect. Optical signals produced by such the distorted temperature fields are simulated and verified experimentally using a 3D metal printer and a sample with artificially carved defects. Three quantities are tested as possible metrics for monitoring the process: temperature, integral intensity, and correlation coefficient. The shapes of the simulated signals qualitatively agree with the experimental signals; this allows for a cautious inference that optical spectroscopy can detect surface defects and, possibly, predict their characters, e.g., inner or protruding. T2 - Colloquium Spectroscopicum Internationale XLII (CSI XLII) CY - Gijon, Spain DA - 30 May 2022 KW - Additive manufacturing KW - Laser metal deposition KW - Optical sensor KW - Optical emission spectroscopy KW - Process control PY - 2022 AN - OPUS4-55063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Accorsi, M. A1 - Tiemann, M. A1 - Wehrhan, L. A1 - Finn, Lauren M. A1 - Cruz, R. A1 - Rautenberg, Max A1 - Emmerling, Franziska A1 - Heberle, J. A1 - Keller, B. G. A1 - Rademann, J. T1 - Pentafluorophosphato-Phenylalanines: Amphiphilic Phosphotyrosine Mimetics Displaying Fluorine-Specific Protein Interactions N2 - Phosphotyrosine residues are essential functional switches in health and disease. Thus, phosphotyrosine biomimetics are crucial for the development of chemical tools and drug molecules. We report here the discovery and investigation of pentafluorophosphato amino acids as novel phosphotyrosine biomimetics. A mild acidic pentafluorination protocol was developed and two PF5-amino acids were prepared and employed in peptide synthesis. Their structures, reactivities, and fluorine-specific interactions were studied by NMR and IR spectroscopy, X-ray diffraction, and in bioactivity assays. The mono-anionic PF5 motif displayed an amphiphilic character binding to hydrophobic surfaces, to water molecules, and to protein-binding sites, exploiting charge and H−F-bonding interactions. The novel motifs bind 25- to 30-fold stronger to the phosphotyrosine binding site of the protein tyrosine phosphatase PTP1B than the best current biomimetics, as rationalized by computational methods, including molecular dynamics simulations. KW - Chemical Biology KW - Drug Development KW - Pentafluorophosphates KW - Phosphotyrosine Biomimetics KW - Protein Tyrosine Phosphatases PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-549984 DO - https://doi.org/10.1002/anie.202203579 SN - 1433-7851 VL - 134 IS - 25 SP - 1 EP - 6 PB - Wiley-VCH GmbH AN - OPUS4-54998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Burgmayer, R. A1 - Bake, Friedrich A1 - Enghardt, L. T1 - Design and Evaluation of a Zero Mass Flow Liner N2 - In this study, the concept of a Zero Mass Flow Liner is evaluated. The concept enables impedance control by the induction of periodic bias flow through the perforated facing sheet of the liner. The periodic bias flow is generated by a secondary high amplitude acoustic actuation. By means of the periodic bias flow, the liner can be tuned to different operating points in a given range of grazing flow velocities. The equivalent fluid impedance model for perforated plates is modified to account for the effects of periodic bias flow and grazing flow. An optimization routine, based on a genetic algorithm, is implemented. The method is applicable to any liner concept and uses the impedance of the lined surface as boundary condition in a numerical simulation. Thereby, a set of liner parameters is derived in order to obtain the desired damping characteristics. Based on the results of the optimization, a Zero Mass Flow Liner is manufactured and consequently evaluated experimentally. The damping characteristics are evaluated in form of the dissipated energy along the lined surface. Prediction and measurements show agreement. The Zero Mass Flow Liner delivers broad band dissipation of high peak value over a range of grazing flow Mach numbers. Under grazing ow conditions, the effect of periodic bias flow is reduced. This poses high energy requirements in high Mach number flow regimes which might restrict the applicability of the Zero Mass Flow concept to grazing flows of low Mach numbers. T2 - 28th AIAA/CEAS Aeroacoustics 2022 Conference CY - Southampton, Great Britain DA - 14.06.2022 KW - Acoustic damping KW - Liner KW - Zero Massflow Liner (ZML) PY - 2022 DO - https://doi.org/10.2514/6.2022-2820 SP - 1 EP - 16 PB - AIAA / CEAS AN - OPUS4-55042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hirschberg, L. A1 - Bake, Friedrich A1 - Hulshoff, S. T1 - Sound production due to main-flow oriented vorticity-nozzle interaction in absence of a net swirl N2 - The downstream acoustic response due to the interaction of main-flow oriented vorticity with a choked nozzle in a swirl-free flow was experimentally demonstrated. The response was obtained by means of impulsive radial air injection in the pipe upstream from the nozzle. The resulting downstream acoustic data are shown to obey a scaling rule that differs, from the one for swirl-nozzle interaction, which according to the literature is proportional to the square of the swirl number. In contrast, here evidence is presented that points to the scaling of main-flow oriented vorticity noise with the cross-sectional average of the square of the transversal velocity at the throat divided by the square of the critical sound speed. T2 - 28th AIAA/CEAS Aeroacoustics 2022 Conference CY - Southampton, Great Britain DA - 14.06.2022 KW - Main-flow oriented vorticity-nozzle interaction KW - Indirect noise PY - 2022 DO - https://doi.org/10.2514/6.2022-3055 SP - 1 EP - 8 PB - AIAA / CEAS AN - OPUS4-55043 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, Cheng-Chieh A1 - Völker, Daniel A1 - Weisbrich, S. A1 - Neitzel, F. ED - Holl, H. T1 - The finite volume method in the context of the finite element method N2 - The finite volume method (FVM), like the finite element method (FEM), is a numerical method for determining an approximate solution for partial differential equations. The derivation of the two methods is based on very different considerations, as they have historically evolved from two distinct engineering disciplines, namely solid mechanics and fluid mechanics. This makes FVM difficult to learn for someone familiar with FEM. In this paper we want to show that a slight modification of the FEM procedure leads to an alternative derivation of the FVM. Both numerical methods are starting from the same strong formulation of the problem represented by differential equations, which are only satisfied by their exact solution. For an approximation of the exact solution, the strong formulation must be converted to a so-called weak form. From here on, the two numerical methods differ. By appropriate choice of the trial function and the test function, we can obtain different numerical methods for solving the weak formulation of the problem. While typically in FEM the basis functions of the trial function and test function are identical, in FVM they are chosen differently. In this paper, we show which trial and test function must be chosen to derive the FVM alternatively: The trial function of the FVM is a “shifted” trial function of the FEM, where the nodal points are now located in the middle of an integration interval rather than at the ends. Moreover, the basis functions of the test function are no longer the same as those of the trial function as in the FEM, but are shown to be a constant equal to 1. This is demonstrated by the example of a 1D Poisson equation. KW - Finite Volume Method KW - Finite Element Method KW - Variational Calculation KW - Numerical Methods PY - 2022 DO - https://doi.org/10.1016/j.matpr.2022.05.460 SN - 2214-7853 VL - 62 SP - 2679 EP - 2683 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-55046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Xiao, J. A1 - Vogl, Jochen A1 - Rosner, M. A1 - Jin, Z. T1 - Boron isotope fractionation in soil-plant systems and its influence on biogeochemical cycling N2 - Boron (B) is an essential mineral nutrient for higher plants. Although B plant nutrition is well studied, the B isotope fractionation at the soil-plant interface, within plant metabolism, and its influence on biogeochemical cycling is not fully understood. Boron concentrations and isotope variations (δ11B) of the dicotyledonous plants of Chenopodium album and Brassica napus and their growing soils along a climatic gradient were analyzed to decipher these unresolved issues of the B behavior. The boron concentrations and δ11B values show an increasing trend from roots to leaves for both plants, while a decreasing trend from flower to shell and to seed for Brassica napus. A large boron isotope fractionation occurs within the plants with median Δ11Bleaf-root ≈ +20‰, which is related to different boron transporters and transportation ways. Formation of borate dimerized rhamnogalacturonan II in cell and B(OH)3 transportation in xylem lead to heavier δ11B values from root to stem and leaf while B(OH)4􀀀 transportation in phloem lead to lighter δ11B values from flower to shell and seed. Although samples cover a distinct transect with systematically different climatic conditions, Δδ11B within the individual plant compartments and between the bulk plants and the soil available B do not show any systematic variation. This suggests that B uptake from the soil into Chenopodium album and Brassica napus occurs without a distinct isotope fractionation at the soil-plant interface (median Δ11Bbulkplant-soil = 􀀀 0.2‰) and plants are able to regulate boron uptake. Both the observed large B fractionation within plant and low or absent B isotope fractionation at the soil-plant interface may have profound implications for the biological and geological B cycle. If this observed boron behavior also exists in other plants, their litters would be an important source for exporting 11B-rich biological material from continental ecosystems via rivers to the global oceans. This may be helpful for the explanation of ocean B cycle and the increasing δ11B values over the Cenozoic. KW - Boron isotopic composition KW - Boron isotope fractionation KW - Soil available boron KW - Biological boron recycling KW - Chenopodium album KW - Brassica napus PY - 2022 DO - https://doi.org/10.1016/j.chemgeo.2022.120972 SN - 0009-2541 VL - 606 SP - 1 EP - 8 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-55031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Brauckmann, C. A1 - Pramann, A. A1 - Rienitz, O. A1 - Schulze, A. A1 - Phukphatthanachai, P. A1 - Vogl, Jochen T1 - Combining Isotope Dilution and Standard Addition - Elemental Analysis in Complex Samples N2 - A new method combining isotope dilution mass spectrometry (IDMS) and standard addition has been developed to determine the mass fractions w of different elements in complex matrices: (a) silicon in aqueous tetramethylammonium hydroxide (TMAH), (b) sulfur in biodiesel fuel, and (c) iron bound to transferrin in human serum. All measurements were carried out using inductively coupled plasma mass spectrometry (ICP–MS). The method requires the gravimetric preparation of several blends (bi)—each consisting of roughly the same masses (mx,i) of the sample solution (x) and my,i of a spike solution (y) plus different masses (mz,i) of a reference solution (z). Only these masses and the isotope ratios (Rb,i) in the blends and reference and spike solutions have to be measured. The derivation of the underlying equations based on linear regression is presented and compared to a related concept reported by Pagliano and Meija. The uncertainties achievable, e.g., in the case of the Si blank in extremely pure TMAH of urel (w(Si)) = 90% (linear regression method, this work) and urel (w(Si)) = 150% (the method reported by Pagliano and Meija) seem to suggest better applicability of the new method in practical use due to the higher robustness of regression analysis. T2 - CITAC Best Paper Award Ceremony CY - Online meeting DA - 21.06.2022 KW - Isotope dilution mass spectrometry KW - Standard addition KW - ICP-MS KW - Blank characterization KW - Silicon KW - Sulfur KW - Transferrin KW - Tetramethylammonium hydroxide KW - Biodiesel fuel KW - Human serum PY - 2022 AN - OPUS4-55032 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Prohaska, T. A1 - Irrgeher, J. A1 - Benefield, J. A1 - Böhlke, J. K. A1 - Chesson, L. A. A1 - Coplen, T. B. A1 - Ding, T. A1 - Dunn, P. J. H. A1 - Gröning, M. A1 - Holden, N. E. A1 - Meijer, H. A. J. A1 - Moossen, H. A1 - Possolo, A. A1 - Takahashi, Y. A1 - Vogl, Jochen A1 - Walczyk, T. A1 - Wang, J. A1 - Wieser, M. E. A1 - Yoneda, S. A1 - Zhu, X.-K. A1 - Meija, J. T1 - Standard atomic weights of the elements 2021 (IUPAC Technical Report) N2 - Following the reviews of atomic-weight determinations and other cognate data in 2015, 2017, 2019 and 2021, the IUPAC (International Union of Pure and Applied Chemistry) Commission on Isotopic Abundances and Atomic Weights (CIAAW) reports changes of standard atomic weights. The symbol Ar(E) was selected for standard atomic weight of an element to distinguish it from the atomic weight of an element E in a specific substance P, designated Ar(E, P). The CIAAW has changed the values of the standard atomic weights of five elements based on recent determinations of terrestrial isotopic abundances: Ar (argon): from 39.948 ± 0.001 to [39.792, 39.963] Hf (hafnium): from 178.49 ± 0.02 to 178.486 ± 0.006 Ir (iridium): from 192.217 ± 0.003 to 192.217 ± 0.002 Pb (lead): from 207.2 ± 0.1 to [206.14, 207.94] Yb (ytterbium): from 173.054 ± 0.005 to 173.045 ± 0.010 The standard atomic weight of argon and lead have changed to an interval to reflect that the natural variation in isotopic composition exceeds the measurement uncertainty of Ar(Ar) and Ar(Pb) in a specific substance. The standard atomic weights and/or the uncertainties of fourteen elements have been changed based on the Atomic Mass Evaluations 2016 and 2020 accomplished under the auspices of the International Union of Pure and Applied Physics (IUPAP). Ar of Ho, Tb, Tm and Y were changed in 2017 and again updated in 2021: Al (aluminium), 2017: from 26.981 5385 ± 0.000 0007 to 26.981 5384 ± 0.000 0003 Au (gold), 2017: from 196.966 569 ± 0.000 005 to 196.966 570 ± 0.000 004 Co (cobalt), 2017: from 58.933 194 ± 0.000 004 to 58.933 194 ± 0.000 003 F (fluorine), 2021: from 18.998 403 163 ± 0.000 000 006 to 18.998 403 162 ± 0.000 000 005 (Ho (holmium), 2017: from 164.930 33 ± 0.000 02 to 164.930 328 ± 0.000 007) Ho (holmium), 2021: from 164.930 328 ± 0.000 007 to 164.930 329 ± 0.000 005 Mn (manganese), 2017: from 54.938 044 ± 0.000 003 to 54.938 043 ± 0.000 002 Nb (niobium), 2017: from 92.906 37 ± 0.000 02 to 92.906 37 ± 0.000 01 Pa (protactinium), 2017: from 231.035 88 ± 0.000 02 to 231.035 88 ± 0.000 01 Pr (praseodymium), 2017: from 140.907 66 ± 0.000 02 to 140.907 66 ± 0.000 01 Rh (rhodium), 2017: from 102.905 50 ± 0.000 02 to 102.905 49 ± 0.000 02 Sc (scandium), 2021: from 44.955 908 ± 0.000 005 to 44.955 907 ± 0.000 004 (Tb (terbium), 2017: from 158.925 35 ± 0.000 02 to 158.925 354 ± 0.000 008) Tb (terbium), 2021: from 158.925 354 ± 0.000 008 to 158.925 354 ± 0.000 007 (Tm (thulium), 2017: from 168.934 22 ± 0.000 02 to 168.934 218 ± 0.000 006) Tm (thulium), 2021: from 168.934 218 ± 0.000 006 to 168.934 219 ± 0.000 005 (Y (yttrium), 2017: from 88.905 84 ± 0.000 02 to 88.905 84 ± 0.000 01) Y (yttrium), 2021: from 88.905 84 ± 0.000 01 to 88.905 838 ± 0.000 002 KW - Argon KW - Ciaaw.org KW - Hafnium KW - Iridium KW - Lead KW - LSVEC KW - Ytterbium PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548443 DO - https://doi.org/10.1515/pac-2019-0603 SN - 0033-4545 VL - 94 IS - 5 SP - 573 EP - 600 PB - De Gruyter Verlag CY - Berlin AN - OPUS4-54844 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kornev, R. A1 - Gornushkin, Igor B. A1 - Nazarov, V. A1 - Shkrunin, V. A1 - Ermakov, A. T1 - Features of hydrogen reduction of SiF4 in ICP plasma N2 - Probe diagnostics is used to determine the electron temperature and electron number density in a low pressure inductively coupled plasma (ICP) ignited in the mixture of SiF4, Ar and H2. Emission spectra of mixtures with different stoichiometry of components are investigated and the electron density distribution function (EDDF) is estimated. The optimal conditions for high conversion of SiF4 into Si are found by studying the dependence of the yield of silicon upon the ratio of reagents. The maximum achieved yield of silicon is 85% under the optimal conditions. Based on the analysis of IR and MS spectra of exhaust gases, 5% of initial SiF4 converts into volatile fluorosilanes. A rate of production of Si is 0.9 g/h at the energy consumption 0.56 kWh /g. KW - Plasma enhanced chemical vapor deposition KW - PECVD KW - Silicon tetrafluoride KW - Emission spectroscopy KW - Probe diagnostics PY - 2022 DO - https://doi.org/10.1016/j.sab.2022.106502 SN - 0584-8547 VL - 195 SP - 106502 PB - Elsevier B.V. AN - OPUS4-55316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pech May, Nelson Wilbur T1 - Photothermal characterization of polyester composites loaded with parallelly arranged graphite rods N2 - One of the biggest challenges in the measurement of thermal properties is to measure inhomogeneous materials This work focuses on measuring the thermal properties of cylindrical polyester resin composite materials loaded with graphite rods oriented in the direction of the resin thickness, varying the graphite concentrations starting from zero to 8 75 of volumetric fraction and changing the distribution of graphite rods inside the polyester matrix. T2 - International Conference in Photoacoustics and Photothermal Phenomena (ICPPP21) CY - Bled, Slovenia DA - 19.06.2022 KW - Heat diffusion KW - Heterogeneous materials PY - 2022 AN - OPUS4-55384 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pech May, Nelson Wilbur T1 - Automatic inspection of surface breaking cracks using laser scanning thermography N2 - In this work, we report on a method for automatic inspection of components using laser scanning thermography, in which the relative motion is performed by a robot to fully inspect complex test objects such as turbine blades. We demonstrate our evaluation algorithms with the aim of automatically detecting surface defects on calibrated specimens. We show the influence of the excitation laser, which can be varied in terms of spot geometry, wavelength, and scan scheme. Additionally, we show some advantages, versatility, and current challenges of using a programmed robot for non-destructive evaluation in thermography. T2 - International Conference in Photoacoustics and Photothermal Phenomena (ICPPP21) CY - Bled, Slovenia DA - 19.06.2022 KW - Flying line thermography KW - Surface breaking defects KW - Canny approach PY - 2022 AN - OPUS4-55386 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shapovalov, O. A1 - Heckel, Thomas A1 - Gaal, Mate A1 - Weiß, S. T1 - External Acoustical Damping on a Metallic Angle Wedge in a High Temperature Resistant Ultrasonic Probe N2 - Ultrasonic probes for high-temperature applications are provided with metallic wedges, which can withstand the contact with the high temperature of the inspected structure. The ultrasonic signal travels within the wedge and gets reflected from its boundaries, causing interference signals called “ghost echoes”. The current work presents an investigation of the additional damping effect provided by porous sintered metal plates applied onto the surface of the wedge. In particular, the study evaluates the effect of damping plate thickness on the interference signal level at different transmission frequencies. Damping plates made of sintered metal SIKA-R 15 AX were attached to a wedge prototype made of steel 1.4301. The study revealed, that the most effective thickness of damping plates in the selected frequency interval of 1 to 4 MHz is equal to 4 mm. The evaluation of the interference signal has shown that the application of such damping plates to the wedge surface contributes to an additional attenuation of an interference signal of 10 to 30 dB after 500 μs of signal propagation. KW - Ultrasonic testing KW - High temperature KW - Acoustical damping KW - Angle wedge KW - Ultrasonic probe PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-553920 DO - https://doi.org/10.1007/s40857-022-00270-9 SN - 0814-6039 SP - 1 EP - 11 PB - Springer AN - OPUS4-55392 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mazzeo, P. P. A1 - Prencipe, M. A1 - Feiler, Torvid A1 - Emmerling, Franziska A1 - Bacchi, A. T1 - On the mechanism of cocrystal mechanochemical reaction via low melting eutectic: A time-resolved in situ monitoring investigation N2 - Mechanochemistry has become a sustainable and attractive cost-effective synthetic technique, largely used within the frame of crystal engineering. Cocrystals, namely, crystalline compounds made of different chemical entities within the same crystal structure, are typically synthesized in bulk via mechanochemistry; however, whereas the macroscopic aspects of grinding are becoming clear, the fundamental principles that underlie mechanochemical cocrystallization at the microscopic level remain poorly understood. Time-resolved in situ (TRIS) monitoring approaches have opened the door to exceptional detail regarding mechanochemical reactions. We here report a clear example of cocrystallization between two solid coformers that proceeds through the formation of a metastable low melting binary eutectic phase. The overall cocrystallization process has been monitored by time-resolved in situ (TRIS) synchrotron X-ray powder diffraction with a customized ball milling setup, currently available at μ Spot beamline at BESSY-II, Helmholtz-Zentrum Berlin. The binary system and the low melting eutectic phase were further characterized via DSC, HSM, and VT-XRPD. KW - Mechanochemistry KW - In situ KW - Cocrystal PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552977 DO - https://doi.org/10.1021/acs.cgd.2c00262 SN - 1528-7505 VL - 22 IS - 7 SP - 4260 EP - 4267 PB - ACS Publ. CY - Washington, DC AN - OPUS4-55297 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kröll, Mirco T1 - Effects of harmonised procedures in tribology testing N2 - i-TRIBOMAT will provide the world's first Open Innovation Test Bed dedicated to analysing and simulating materials in tribological systems. In order to make necessary results of tribological tests comparable, harmonised ways to produce data are mandatory. Many sources influence the outcome of a Tribological test. Different approaches of institutes were evaluated in best practices via quality management tools minimising the impact on results. T2 - 7th World Tribology Congress - WTC 2022 CY - Lyon, France DA - 11.07.2022 KW - Tribology KW - i-TRIBOMAT KW - Characterisation KW - Digitalisation KW - Harmonisation KW - Round robin tests KW - Interlaboratory tests PY - 2022 AN - OPUS4-55317 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zabala, A. T1 - Ball-on-flat linear reciprocating tests: Critical assessment of wear volume determination methods N2 - This work presents a critical assessment of wear volume determination methods for ball-on-flat linear reciprocating sliding tribological tests. T2 - 7th World Tribology Congress - WTC 2022 CY - Lyon, France DA - 11.07.2022 KW - Wear KW - Sliding KW - Surface KW - Analysis PY - 2022 AN - OPUS4-55319 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lecompagnon, Julien A1 - Hirsch, Philipp Daniel A1 - Rupprecht, C. A1 - Ziegler, Mathias ED - Mendioroz, A. ED - Avdelidis, N. P. T1 - Thermographic testing using 2D pseudo-random illumination and photothermal super resolution reconstruction N2 - Due to the diffusive nature of heat propagation in solids, the detection and resolution of internal defects with active thermography based non-destructive testing is commonly limited to a defect-depth-to-defect-size ratio greater than or equal to one. In the more recent past, we have already demonstrated that this limitation can be overcome by using a spatially modulated illumination source and photothermal super resolution-based reconstruction. Furthermore, by relying on compressed sensing and computational imaging methods we were able to significantly reduce the experimental complexity to make the method viable for investigating larger regions of interest. In this work we share our progress on improving the defect/inhomogeneity characterization using fully 2D spatially structured illumination patterns instead of scanning with a single laser spot. The experimental approach is based on the repeated blind pseudo-random illumination using modern projector technology and a high-power laser. In the subsequent post-processing, several measurements are then combined by taking advantage of the joint sparsity of the defects within the sample applying 2D-photothermal super resolution reconstruction. Here, enhanced nonlinear convex optimization techniques are utilized for solving the underlying ill-determined inverse problem for typical simple defect geometries. As a result, a higher resolution defect/inhomogeneity map can be obtained at a fraction of the measurement time previously needed. T2 - Thermosense: Thermal Infrared Applications XLIV CY - Orlando, Florida, USA DA - 05.04.2022 KW - Thermography KW - Super resolution KW - NDT KW - Material testing KW - Internal defects KW - DMD KW - DLP PY - 2022 DO - https://doi.org/10.1117/12.2618562 SN - 0277-786X VL - 12109 SP - 1 EP - 10 PB - SPIE AN - OPUS4-54909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lugovtsova, Yevgeniya T1 - Reconstruction of Elastic Constants of Isotropic and Anisotropic Materials using Ultrasonic Guided Waves N2 - Acoustic methods are ideally suited for determining the mechanical properties of different materials non-destructively. The availability of such methods is particularly important for fiber-reinforced polymers (FRPs) because their properties strongly depend on the manufacturing process and in-service conditions. Since FRPs are mostly used in thin-walled components, properties can be derived from the dispersion curves of ultrasonic guided waves (UGWs). Our approach is based on an inverse procedure in which the numerically calcu-lated dispersion curves are fitted to the measured curves. The acquisition is done by applying a broadband piezoelectric transducer (PZT) to excite and a 3D laser Doppler vibrometer (3D LDV) to record the waves. Compared to the ap-proaches based on laser excitation, the PZT provides a better signal-to-noise ra-tio because more energy is brought into the structure. Whereas the 3D LDV compared to a 1D LDV or a PZT allows capturing in-plane and out-of-plane components and thus providing more dispersion information. Since the inverse procedure requires many iterations before elastic properties are retrieved, an ef-ficient tool for the calculation of the dispersion curves is necessary. For this, the Scaled Boundary Finite Element Method is used. All in all, a good agreement between theoretical and experimental curves is demonstrated. T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2022) CY - Palermo, Italy DA - 04.07.2022 KW - Lamb waves KW - Elastic waves KW - Fibre-reinforced polymers KW - Inverse procedure KW - Scaled Boundary Finite Element Method PY - 2022 AN - OPUS4-55236 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Even, Morgane T1 - Development of a procedure for the analysis of the emissions of VVOCs N2 - Several aspects were explored towards the standardization of a suitable procedure. The use of gaseous standards is necessary and a standard gas mixture containing 60 substances was successfully generated and employed for further investigations. The suitability of different chromatography columns was addressed: The use of PLOT (Porous Layer Open Tubular) columns is well suitable for VVOC analysis. The recoveries of the 60 analytes on several adsorbents and their combinations were determined: A combination of a graphitized carbon black and a carbon molecular sieve showed great results for all analytes. Carbon molecular sieves adsorb water which can impair the analysis. Different options such as purging, the use of a drying system or splitting were investigated for water removal. This contribution will present experimental results supporting the standardization of a method for VVOC analysis. T2 - Indoor Air conference CY - Kuopio, Finland DA - 12.06.2022 KW - Analytical method KW - EN 16516 KW - ISO 16000-6 KW - VVOCs PY - 2022 AN - OPUS4-55282 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Raab, A. A1 - Vogl, Jochen A1 - Solovyev, N. T1 - Isotope signature of iron, copper and zinc in mouse models (L66 and 5XFAD) and their controls used for dementia research N2 - Introduction: The influence of copper, iron and zinc concentrations on the formation of ß-amyloid plaques and neurofibrillary tangles in Alzheimer’s disease (AD) is widely discussed in the community. The results from human and animal studies so far are mixed with some studies showing a correlation and others not. From a number of studies, it is known that disease state and isotopic composition of essential elements can be coupled. Aim: The aim of the study was to identify changes in element content and isotopic composition in two transgenic mouse models used in AD research compared to their genetic WT relatives and to establish whether element content and isotopic signature between different laboratories is comparable. Methods: ß-amyloid (5xFAD) and tau overexpressing (L66) mice together with their matching wild-types were bred at dedicated facilities in accordance with the European Communities Council Directive (63/2010/EU). Serum and brain were sampled after sacrifice and the samples distributed among the participants of the study. The tissues were acid digested for total element determination and high-precision isotope ratio determination. Element content was determined by either sector-field or quadrupole-based inductively coupled plasma mass spectrometry (ICPMS). For the determination of isotope ratios multi-collector ICPMS was used. Results: Total copper content was significantly higher for L66 and their matched WT compared to 5xFAD and WT. Brains of L66 mice contained more Fe in brain than their WT, Zn and Cu were not significantly different between L66 and WT. Whereas 5xFAD mice had a slightly lower Cu and slightly higher Zn concentration in brain compared to WT. The isotopic signature in brain of L66 mice for Fe was different from their controls, whereas Zn isotope ratios were influenced in 5xFAD mice compared to their WT. The Cu isotopic ratio did not seem to be influenced in either strain. In serum, the shifts were less pronounced. Conclusion: Even though neither Tau-protein nor amyloid precursor protein are known to be metal-dependent / -containing proteins, the overexpression of both influences the Fe, Cu and Zn metabolism in brain and to some extent also in serum as can be seen not only using total element determination but probably more clearly studying the isotopic signature of Fe, Cu and Zn. T2 - The International Conference of Trace Elements and Minerals (ICTEM) 2022 CY - Aachen, Germany DA - 05.06.2022 KW - Isotope ratio KW - Isotope delta value KW - Metrology KW - Alzheimer disease KW - Measurement uncertainty PY - 2022 AN - OPUS4-55204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Olino, M. A1 - Lugovtsova, Yevgeniya A1 - Memmolo, V. A1 - Prager, Jens T1 - Temperature Compensation Strategies for Lamb Wave Inspection using Distributed Sensor Networks N2 - The application of temperature compensation strategies is crucial in structural health monitoring approaches based on guided waves. Actually, the varying temperature influences the performance of the inspection system inducing false alarms or missed detection, with a consequent reduction of reliability. This paper quantitatively describes a method to compensate the temperature effect, namely the optimal baseline selection (OBS), extending its application to the case of distributed sensor networks (DSN). The effect of temperature separation between baseline time-traces in OBS are investigated considering multiple couples of sensors employed in the DSN. A combined strategy that uses both OBS and frequent value warning is considered. Theoretical results are compared, using data from two several experiments, which use different frequency analysis with either predominantly A0 mode or S0 mode data or both. The focus is given on the fact that different paths are available in a sensor network and several possible combination of results are available. Nonetheless, introducing a frequent value warning it is possible to increase the efficiency of the OBS approach making use of fewer signal processing algorithms. These confirm that the performance of OBS quantitatively agrees with predictions and also demonstrate that the use of compensation strategies improve detectability of damage. T2 - IEEE International Workshop on Metrology for AeroSpace CY - Pisa, Italy DA - 27.06.2022 KW - Ultrasound KW - Ultrasonic Guided Waves KW - Structural Health Monitoring PY - 2022 SN - 978-1-6654-1076-2 DO - https://doi.org/10.1109/MetroAeroSpace54187.2022.9856029 SP - 598 EP - 601 AN - OPUS4-55268 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mueller, I. A1 - Freitag, S. A1 - Memmolo, V. A1 - Moix-Bonet, M. A1 - Möllenhoff, K. A1 - Golub, M. A1 - Sridaran Venkat, R. A1 - Lugovtsova, Yevgeniya A1 - Eremin, A. A1 - Moll, J. A1 - Tschöke, K. ED - Rizzo, P. ED - Milazzo, A. T1 - Performance Assessment for Artificial Intelligence-Based Data Analysis in Ultrasonic Guided Wave-Based Inspection: A Comparison to Classic Path-Based Probability of Detection N2 - Performance assessment for GuidedWave (GW)-based Structural Health Monitoring (SHM) systems is of major importance for industrial deployment. With conventional feature extraction methods like damage indices, pathbased probability of detection (POD) analysis can be realized. To achieve reliability quantification enough data needs to be available, which is rarely the case. Alternatives like methods for performance assessment on system level are still in development and in a discussion phase. In this contribution, POD results using an Artificial Intelligence (AI)-based data analysis are compared with those delivered by conventional data analysis. Using an open-access dataset from Open Guided Wave platform, the possibility of performance assessment for GW-based SHM systems using AI-based data analysis is shown in detail. An artificial neural network (ANN) classifier is trained to detect artificial damage in a stiffened CFRP plate. As input for the ANN, classical damage indicators are used. The ANN is tested to detect damage at another position, whose inspection data were not previously used in training. The findings show very high detection capabilities without sorting any specific path but only having a global view of current damage metrics. The systematic evaluation of the ANN predictions with respect to specific damage sizes allows to compute a probability of correct identification versus flaw dimension, somehow equivalent to and compared with the results achieved through classic path-based POD analysis. Also, sensitive paths are detected by ANN predictions allowing for evaluation of maximal distances between path and damage position. Finally, it is shown that the prediction performance of the ANN can be improved significantly by combining different damage indicators as inputs. T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2022) CY - Palermo, Italy DA - 04.07.2022 KW - Probability of Detection KW - Composites KW - Open Guided Waves Platform KW - Artificial Neural Network PY - 2022 SN - 978-3-031-07257-4 DO - https://doi.org/10.1007/978-3-031-07258-1 SN - 2366-2557 VL - 2 SP - 953 EP - 961 PB - Springer CY - Cham, Switzerland AN - OPUS4-55269 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tschöke, K. A1 - Mueller, I. A1 - Memmolo, V. A1 - Sridaran Venkat, R. A1 - Golub, M. A1 - Eremin, A. A1 - Moix-Bonet, M. A1 - Möllenhoff, K. A1 - Lugovtsova, Yevgeniya A1 - Moll, J. A1 - Freitag, S. ED - Rizzo, P. ED - Milazzo, A. T1 - A Model-Assisted Case Study Using Data from Open Guided Waves to Evaluate the Performance of Guided Wave-Based Structural Health Monitoring Systems N2 - Reliability assessment of Structural Health Monitoring (SHM) systems poses new challenges pushing the research community to address many questions which are still open. For guided wave-based SHM it is not possible to evaluate the system performance without taking into account the target structure and applied system parameters. This range of variables would result in countless measurements. Factors like environmental conditions, structural dependencies and wave characteristics demand novel solutions for performance analysis of SHM systems compared to those relying on classical non-destructive evaluation. Such novel approaches typically require model-assisted investigations which may not only help to explain and understand performance assessment results but also enable complete studies without costly experiments. Within this contribution, a multi input multi output approach using a sparse transducer array permanently installed on a composite structure to excite and sense guided waves is considered. Firstly, the method and the analysis of path-based performance assessment are presented considering an open-access dataset from the Open Guided Wave platform. Then, a performance analysis of a guided wave-based SHM system using Probability of Detection is presented. To explain some unexpected results, the model-assisted investigations are used to understand the physical phenomena of wave propagation in the test specimen including the interaction with damage. Finally, issues and future steps in SHM systems’ performance assessment and their development are discussed. T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2022) CY - Palermo, Italy DA - 04.07.2022 KW - Performance assessment KW - Ultrasonic Guided Waves KW - Open Guided Waves Platform PY - 2022 SN - 978-3-031-07257-4 DO - https://doi.org/10.1007/978-3-031-07258-1 SN - 2366-2557 VL - 2 SP - 938 EP - 944 PB - Springer CY - Cham, Switzerland AN - OPUS4-55270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -