TY - CONF A1 - Pauw, Brian Richard T1 - AI/ML starts with data, …a practical example N2 - A brief introduction to the efforts we have done in our lab towards AI/ML analysis of SAXS data. For this, we need to extend the data with an extensive, structured hierarchy of metadata and associated data. A practical look into the information stored in our files, and the organization of the files in a data catalog is presented. T2 - Benchmarking for AI for Science at the Exascale A2 Workshop for Materials Science CY - Online meeting DA - 23.11.2020 KW - Small angle scattering KW - Machine learning KW - Data organization KW - Data curation KW - Metadata structuring PY - 2020 AN - OPUS4-51660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmitt, M. A1 - Altmann, Korinna A1 - Fengler, Petra A1 - Gehde, M. T1 - Air-based polyethylene fragmentation with high yield to form microplastic particles as reference material candidates N2 - Microplastic particles with sizes between 1 to 1000 μm are widely distributed worldwide. Origin, transport pathways and fate are poorly known, as sampling, sample preparation and detection methods are major challenges. In addition, reference materials that mimic environmental particles are lacking. Most challenging is the yield of MP particle production and the need for resource-intensive grinding with liquid nitrogen. In this paper, a machine is designed to produce aged microplastic particles as reference material candidates with high yield. The machine is based on ultraviolet aging of a thin foil and mechanical fragmentation using clean air. An example of aging and fragmentation of high density polyethylene with additional physical and chemical characterization of shape, size, aging state by carbonyl index and density is presented. KW - Microplastics KW - Degradation of polyethylene KW - Air fragmentation KW - Microplastics reference material PY - 2023 DO - https://doi.org/10.1002/appl.202200121 SP - 1 EP - 18 PB - Wiley online library AN - OPUS4-57203 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 - Tiitta, M. A1 - Tiitta, V. A1 - Gaal, Mate A1 - Heikkinen, J. A1 - Lappalainen, R. A1 - Tomppo, L. T1 - Air-coupled ultrasound detection of natural defects in wood using ferroelectret and piezoelectric sensors N2 - Air-coupled ultrasound was used for assessing natural defects in wood boards by through-transmission scanning measurements. Gas matrix piezoelectric (GMP) and ferroelectret (FE) transducers were studied. The study also included tests with additional bias voltage with the ferroelectret receivers. Signal analyses, analyses of the measurement dynamics and statistical analyses of the signal parameters were conducted. After the measurement series, the samples were cut from the measurement regions and the defects were analyzed visually from the cross sections. The ultrasound responses were compared with the results of the visual examination of the cross sections. With the additional bias voltage, the ferroelectret measurement showed increased signal-to-noise ratio, which is especially important for air-coupled measurement of high-attenuation materials like wood. When comparing the defect response of GMP and FE sensors, it was found that FE sensors had more sensitive dynamic range, resulting from better s/n ratio and short response pulse. Classification test was made to test the possibility of detecting defects in sound wood. Machine learning methods including decision trees, k-nearest neighbor and support vector machine were used. The classification accuracy varied between 72 and 77% in the tests. All the tested machine learning methods could be used efficiently for the classification. KW - Air-coupled transducers KW - Wood KW - Ultrasound KW - Ultrasonic imaging KW - Ferroelectret KW - Machine learning PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509503 DO - https://doi.org/10.1007/s00226-020-01189-y SP - 1 EP - 14 PB - Springer AN - OPUS4-50950 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gantois, F. T1 - ALCOREF "Certified forensic alcohol reference materials" N2 - The poster presents the main achievements of the capacity building project ALCOREF “Forensic alcohol reference materials”. The project was part of the European Metrology Programme for Innovation and Research (EMPIR). Altogether 43 certified ethanol in water reference materials (CRMs) in the mass fraction range of 0.1 to 7 mg/g were developed by project partners. These CRMS are suitable for the calibration and verification of evidential breath alcohol analysers according to the requirements of the International Organisation of Legal Metrology (OIML). Furthermore, 10 new or improved Calibration and Measurement Capability (CMC) claims for purity assessment of ethanol and ethanol quantification were prepared. Newly established measurement capabilities and the new CRMs were successfully tested in three intercomparisons conducted as official intercomparisons of EURAMET Technical Committee for Metrology in Chemistry. T2 - 20th International Metrology Congress CIM CY - Lyon, France DA - 07.09.2021 KW - Certified reference material KW - EMPIR project KW - Evidential breath alcohol measurement PY - 2021 AN - OPUS4-53288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gantois, F. T1 - ALCOREF "Certified forensic alcohol reference materials" N2 - The presentation provides an overview of the EMPIR project ALCOREF “Certified forensic alcohol reference materials”. Results of an EURAMET intercomparison of ethanol in water reference materials developed in the project are presented, and two different statistical models for the key comparison reference function are discussed, the Frequentist approach and a Bayesian approach. T2 - CCQM Organic Analysis Working Group Meeting CY - Online meeting DA - 04.05.2021 KW - Certified reference material KW - EMPIR project KW - Interlaboratory comparison PY - 2021 AN - OPUS4-52852 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 - Tavernaro, Isabella T1 - Amorphous, fluorescent silica particles for bioimaging applications N2 - Nowadays amorphous silica nanoparticles (SiO2 NP) are one of the most abundant engineered nanomaterials, with an annual production of hundreds of thousands of tons, that are used in a broad field of industrial products and processes. Since SiO2 NP are highly stable and easily produced on a large scale at low cost, they are widely employed as fillers for rubbers and composites, absorbents, catalysts, advanced coating additives as well as plant growth agents in agriculture, anti-caking agents in food products, or as carrier material in cosmetic industry. Moreover, they are promising candidates for colloidal scaffolds in biomedical applications like bioimaging, sensing or controlled drug delivery. SiO2 NP modified with luminescent chromophores have several advantages as compared to conventional molecular probes like enhanced brightness, ease of designing ratiometric systems, and increased photostability. Here we present our work on multicolored SiO2 NP for imaging and sensing applications. T2 - FUNGLASS Workshop CY - Berlin, Germany DA - 06.03.2024 KW - Sensors KW - Nano KW - Particles KW - Silica KW - Luminescence KW - Fluorescence KW - Quality assurance KW - Method KW - Synthesis KW - Dye KW - pH KW - Surface analysis PY - 2024 AN - OPUS4-62167 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Flierl, Lukas A1 - Rienitz, Olaf A1 - Vogl, Jochen A1 - Pramann, Axel T1 - An advancement of the gravimetric isotope mixture method rendering the knowledge of the spike purity superfluous N2 - The gravimetric isotope mixture method is the primary method to determine absolute isotope ratios. This method, however, depends on the existence of suitable spike materials and knowledge of their purities. Determining the purity of the spikes can be tedious and labour-intensive. In this publication, an advancement of the gravimetric isotope mixture method, rendering the determination of the purity of the spike materials unnecessary, is presented. The advancement combines mass spectrometry and ion chromatography leading to an approach being independent of the purity of the spike materials. In the manuscript the mathematical background and the basic idea of the novel approach are described using a two-isotope system like copper or lithium. KW - Isotope amount ratios KW - Metrology KW - Mass spectrometry KW - Ion chromatography PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608726 DO - https://doi.org/10.1007/s00216-024-05465-9 SP - 5325 EP - 5333 PB - Springer Science and Business Media LLC AN - OPUS4-60872 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerbeit, Marco T1 - An apparatus for generating reproducible and scalable shock waves in the free field N2 - A simple test bench was set up on the BAM test site to investigate shock waves caused by gas detonations. The aim was to build a simple mobile test bench that can be used for various applications, to demonstrate the vaildity and for comparison with other test benches. For this purpose a balloon filled with acetylene and oxygen at atmospheric pressure with an electric ignitor was used. The characteristics of the shock waves can be scaled via the gaseous mixture, the filling quantity of the balloon and the distance to the sensors. Pressure sensors were set up around the balloon at various distances to measure the shock. With the help of the high-speed recordings and the Rankine Hugoniot equations, the shock front pressure was estimated and compared with the results of the pressure sensors. In order to validate the results of this test bench, they were compared with an experiment using plastic explosive no. 4 . These agreed well with the results. Overall, symmetrical undisturbed scalable shock waves can be generated with the setup. Only the reproducibility, which is comparatively poor to open shock tubes due to the influence of wind, had to be improved. T2 - 35th International Symposium on Shock Waves (ISSW35) CY - Brisbane, Australia DA - 07.07.2025 KW - Shock waves KW - BOS KW - Gas detonation PY - 2025 AN - OPUS4-63786 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gottu Mukkula, A. R. A1 - Kern, Simon A1 - Salge, M. A1 - Holtkamp, M. A1 - Guhl, Svetlana A1 - Fleischer, C. A1 - Meyer, Klas A1 - Remelhe, M. A1 - Maiwald, Michael A1 - Engell, S. T1 - An Application of Modifier Adaptation with Quadratic Approximation on a Pilot Scale Plant in Industrial Environment N2 - The goal of this work is to identify the optimal operating input for a lithiation reaction that is performed in a highly innovative pilot scale continuous flow chemical plant in an industrial environment, taking into account the process and safety constraints. The main challenge is to identify the optimum operation in the absence of information about the reaction mechanism and the reaction kinetics. We employ an iterative real-time optimization scheme called modifier adaptation with quadratic approximation (MAWQA) to identify the plant optimum in the presence of plant-model mismatch and measurement noise. A novel NMR PAT-sensor is used to measure the concentration of the reactants and of the product at the reactor outlet. The experiment results demonstrate the capabilities of the iterative optimization using the MAWQA algorithm in driving a complex real plant to an economically optimal operating point in the presence of plant-model mismatch and of process and measurement uncertainties. KW - Process Analytical Technology KW - Online NMR Spectroscopy KW - Process Industry KW - Iterative real-time optimization KW - Modifier adaptation KW - Plant-model mismatch KW - Reactor control KW - CONSENS PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-524531 DO - https://doi.org/10.1016/j.ifacol.2020.12.685 SN - 1522-2640 VL - 53 IS - 2 SP - 11773 EP - 11779 PB - Elsevier CY - Amsterdam AN - OPUS4-52453 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 - Given, Joseph T1 - An automatic system for categorizing and quantifying human factors N2 - Human factors (HF) are little understood, and particularly in non-destructive testing (NDT) experimental data is rare, samples are often small, and statistical methods are rarely used to evaluate results. HF have been widely implicated in major occurrences of technical failure, for example at North Anna Power Plant and on United Airlines Flight 232. Understanding HF is vital for reliable detection and prevention of failures. Reliability assessments, though known to be affected by intrinsic capability, application factors, and HF, have thus far only concentrated to a sufficient degree on intrinsic capability. The addition of HF to that assessment has proven difficult due to the lack of a method of quantifying HF. This paper presents the first attempt from a psychological perspective to quantify HF from qualitative data. HF data was derived from qualitative human-oriented Failure Modes and Effects Analysis (Human-FMEA) workshops for visual inspection of tunnels by laser scanning and for ultrasonic testing of welds. Data was collected on human failure modes, causes, consequences and preventive measures, as well as eliciting a risk priority number (RPN). Using this data, a system of quantitative weightings was created to allocate errors to inductively derived HF categories for further allocation to existing HF categorisation models. This weighting model proved useful for creating quantitative summaries of HF, informing and validating qualitative FMEA results, and comparing existing HF categorisation models. Further potential lies within a planned interface to quantitative reliability assessment methods such as POD (Probability of Detection). While providing quantifications, the method retains a qualitative and holistic nature, can, thus, bridge the gap between psychological and engineering concerns of HF and reliability, contributing to future interdisciplinary work. T2 - SPIE Smart Structures + Nondestructive Evaluation, 2023 CY - Long Beach, CA, USA DA - 12.03.2023 KW - Quantification KW - Human-FMEA KW - Human Factors PY - 2023 DO - https://doi.org/10.1117/12.2658407 SN - 0277-786X VL - 12491 SP - 1 EP - 15 PB - SPIE (The International Society for Optical Engineering) CY - Bellingham, Wash. AN - OPUS4-57928 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 - INPR A1 - Baloh, P. A1 - Bauer, L. A1 - Bendová, A. A1 - Čermák, P. A1 - Fellner, K. A1 - Ghanathe, M. A1 - Hernández Alvarez, O. E. A1 - Hricov, Š. A1 - Jochum, J. K. A1 - Kotvytska, L. A1 - Kumar, S. A1 - Labh, A. A1 - Machovec, P. A1 - Pauw, Brian Richard A1 - Ramszová, K. A1 - Walz, E. A1 - Wild, P. T1 - An exercise in open data: Triple axis data on Si single crystal N2 - Efforts are rising in opening up science by making data more transparent and more easily available, including the data reduction and evaluation procedures and code. A strong foundation for this is the F.A.I.R. principle, building on Findability, Accessibility, Interoperability, and Reuse of digital assets, complemented by the letter T for trustworthyness of the data. Here, we have used data, which was made available by the Institute Laue-Langevin and can be identified using a DOI, to follow the F.A.I.R.+T. principle in extracting, evaluating and publishing triple axis data, recorded at IN3. KW - Open data KW - Neutron diffraction KW - Analysis KW - Open science PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-562257 DO - https://doi.org/10.48550/arXiv.2010.12086 SN - 2331-8422 SP - 1 EP - 4 PB - Cornell University CY - Ithaca, NY AN - OPUS4-56225 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Willms, Thomas A1 - Kryk, Holger A1 - Hampel, Uwe T1 - An improved method for the analysis of the reaction products of the partial isobutane oxidation by gas chromatography using a green solvent N2 - In the present work, an improved GC/MS method for the analysis of the reaction products of the non-catalytic partial oxidation of isobutane at a starting temperature of 25°C has been developed and compared to a previously published method. Two green GC-solvents (dimethyl carbonate (DMC), diethyl carbonate (DEC)) and several internal standards (hexane, benzene, toluene, DEC) have been tested. The separation of the products at low retention times (methanol, isobutane, isobutene) could be significantly improved. For the liquid main products t-butyl hydroperoxide (TBHP), di-t-butyl peroxide (DTBP), t-butanol (TBA), propanone and most trace products (isopropanol, isobutanal, methyl formate, isopropyl formate, t-butyl formate and some acetates – 24 compounds in total), a coefficient of determination CoD > 0.999 has been achieved. For all weighing and GC/MS measurements uncertainties have been calculated. The peaks of the peak pair t-butyl formate (CoD >0.999) and isobutanol (CoD >0.99), have been simulated and used for calibrations. DEC gave a decomposition of TBHP on the column. With DMC, a problem of peak purity of TBHP appeared but could be resolved. The use of the green solvent DMC, compared to also studied traditional solvents like heptane and toluene, proved to be very beneficial, since it also permitted to determine polar compounds, e. g. carbon dioxide and formic acid. KW - GC/MS KW - Green solvent KW - Method development KW - Peroxide KW - Measurement uncertainties KW - Oxidation products KW - Simulation PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-632026 DO - https://doi.org/10.1016/j.chroma.2025.465892 SN - 0021-9673 VL - 1753 SP - 1 EP - 16 PB - Elsevier CY - Amsterdam AN - OPUS4-63202 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Fabian T1 - An improved method for the determination of PFAS using HR-CS-GFMAS via GaF detection N2 - Per- and polyfluorinated alkyl substances (PFASs) are a group of over 4730 individual compounds. Several PFASs are extremely persistent, bioaccumulative and toxic. The analysis of PFASs is challenging because of their various chemical and physical properties as well as the high number of compounds. Target-based approaches (e.g., LC-MS/MS) are limited to the availability of analytical grade standards and are not suitable for the analysis of new/unknown PFASs and transformation products. Therefore, PFAS sum parameter methods become increasingly important to indicate realistic PFAS pollution levels. PFAS sum parameters display the proportion of organically bound fluorine that can either be extracted (EOF) or adsorbed to activated carbon (AOF). For the instrumental analysis of such sum parameters, a fluorine selective detector is needed. High resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) is a sensitive and highly selective tool for fluorine determination. The method is based on the in situ formation of diatomic gallium-mono fluoride (GaF) in a graphite furnace at a temperature of 1550°C. The molecular absorption of GaF can be detected at its most sensitive wavelength at 211.248 nm providing limits of quantification of c(F) 2.7 µg/L. Here, we present an improved method for the determination of PFASs using HR-CS-GFMAS via GaF detection. The optimized method includes a Ga pretreatment as described by Gawor et al. resulting in overall lower detection limits. Furthermore, during optimization the influence of species-specific responses during HR-CS-GFMAS analysis was reduced resulting in a more accurate determination of PFAS sum parameters. To test the applicability of the improved method, we analyzed soil samples from a former fire-fighting training area combining the improved method for detection with our previously optimized extraction method for EOF determination in soils. T2 - ESAS - CSSC CY - Brno, Czech Republic DA - 04.09.2022 KW - PFAS KW - HR-CS-GFMAS KW - Fluorine PY - 2022 AN - OPUS4-55782 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Fabian T1 - An improved method for the determination of PFAS using HR-CS-GFMAS via GaF detection N2 - Per- and polyfluorinated alkyl substances (PFASs) are a group of over 4730 individual compounds. Several PFASs are extremely persistent, bioaccumulative and toxic. The analysis of PFASs is challenging because of their various chemical and physical properties as well as the high number of compounds. Target-based approaches (e.g., LC-MS/MS) are limited to the availability of analytical grade standards and are not suitable for the analysis of new/unknown PFASs and transformation products. Therefore, PFAS sum parameter methods become increasingly important to indicate realistic PFAS pollution levels. PFAS sum parameters display the proportion of organically bound fluorine that can either be extracted (EOF) or adsorbed to activated carbon (AOF). For the instrumental analysis of such sum parameters, a fluorine selective detector is needed. High resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) is a sensitive and highly selective tool for fluorine determination. The method is based on the in situ formation of diatomic gallium-mono fluoride (GaF) in a graphite furnace at a temperature of 1550°C. The molecular absorption of GaF can be detected at its most sensitive wavelength at 211.248 nm providing limits of quantification of c(F) 2.7 µg/L. Here, we present an improved method for the determination of PFASs using HR-CS-GFMAS via GaF detection. The optimized method includes a Ga pretreatment as described by Gawor et al. resulting in overall lower detection limits. Furthermore, during optimization the influence of species-specific responses during HR-CS-GFMAS analysis was reduced resulting in a more accurate determination of PFAS sum parameters. To test the applicability of the improved method, we analyzed soil samples from a former fire-fighting training area combining the improved method for detection with our previously optimized extraction method for EOF determination in soils. T2 - SALSA - Communicating Make and Measure 2022 CY - Berlin, Germany DA - 15.09.2022 KW - PFAS KW - HR-CS-GFMAS KW - Fluorine PY - 2022 AN - OPUS4-55783 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Fabian T1 - An improved method for the determination of PFASs using HR CS GFMAS via GaF detection N2 - Introduction Per- and polyfluorinated alkyl substances (PFASs) are a group of over 4730 individual compounds. Several PFASs are extremely persistent, bioaccumulative and toxic. The analysis of PFASs is challenging because of their various chemical and physical properties as well as the high number of compounds. Target-based approaches (e.g., LC-MS/MS) are limited to the availability of analytical grade standards and are not suitable for the analysis of new/unknown PFASs and transformation products. Therefore, PFAS sum parameter methods become increasingly important to indicate realistic PFAS pollution levels. Methods For the instrumental analysis of such sum parameters, a fluorine selective detector is needed. In our study we used high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) which is a sensitive and highly selective tool for fluorine determination. The method is based on the in situ formation of diatomic gallium-mono fluoride (GaF) in a graphite furnace at a temperature of 1550°C. The molecular absorption of GaF can be detected at its most sensitive wavelength at 211.248 nm providing limits of quantification of c(F) 2.7 µg/L. Results Here, we present an improved method for the determination of PFASs using HR-CS-GFMAS via GaF detection. The optimized method includes a modifier pretreatment step using a mixture of Mg, Pd and Zr and a correction measurement using perfluorooctanoic acid. The combination of both resulted in increased accuracy and precision as well as overall lower detection limits. Furthermore, during optimization the influence of species-specific responses during HR-CS-GFMAS analysis was reduced resulting in a more accurate determination of PFAS sum parameters. To test the applicability of the improved method, we analysed soil samples from a former fire-fighting training area combining the improved method for detection with our previously optimized extraction method for extractable organically bound fluorine (EOF) determination in soils. Innovative aspects • Highly sensitive and selective method for fluorine/PFASs analysis based on HR-CS-GFMAS • Increased accuracy for the determination of EOF • Reduction of PFAS species-specific responses by optimized modifier conditions T2 - ANAKON23 CY - Vienna, Austria DA - 11.04.2023 KW - PFAS KW - HR-CS-GFMAS KW - Fluorine PY - 2023 AN - OPUS4-57409 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - An interlaboratory comparison on measuring the chemical composition of functionalized graphene nanoplatelets N2 - The results of the international interlaboratory comparison ""Chemical Composition of functionalized graphene with X-ray photoelectron spectroscopy (XPS) under the auspice of VAMAS TWA 2 (Surface Chemical Analysis) will be presented. T2 - Kratos German User Meeting 2023 CY - Berlin, Germany DA - 25.10.2023 KW - Graphene KW - Interlaboratory Comparison KW - X-ray photoelectron spectroscopy PY - 2023 AN - OPUS4-58683 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bintz, Thilo T1 - An NMR tomograph for building materials - applications , experimental studies and limitations N2 - Introduction of the NMR Tomograph of Department 8.0 at BAM, the applications, technical limitations, and uses in laboratory studies. T2 - International Conference on Electromagnetic Wave Interaction with Water and Moist Substances (ISEMA) 2021 CY - Kiel, Germany DA - 26.07.2021 KW - NMR relaxometry KW - NMR imaging KW - Sensitivity KW - Building materials PY - 2021 N1 - Geburtsname von Munsch, Sarah Mandy: Nagel, S. M. - Birth name of Munsch, Sarah Mandy: Nagel, S. M. AN - OPUS4-53043 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bintz, Thilo A1 - Munsch, Sarah Mandy A1 - Stelzner, Ludwig A1 - Lauinger, Robert A1 - Schmidt, Wolfram A1 - Kruschwitz, Sabine T1 - An NMR tomograph for building materials - applications, experimental studies and limitations - N2 - A summary of the possibilities, technical limitations and application examples for a unique NMR tomograph at BAM. T2 - 13th International Conference on Electromagnetic Wave Interaction with Water and Moist Substances (ISEMA), 2021 CY - Kiel, Germany DA - 27.06.2021 KW - Relaxation time distribution KW - NMR imaging KW - Capillary suction PY - 2021 SN - 978-1-7281-8738-9 N1 - Geburtsname von Munsch, Sarah Mandy: Nagel, S. M. - Birth name of Munsch, Sarah Mandy: Nagel, S. M. SP - 106 EP - 110 PB - IEEE AN - OPUS4-53116 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Moreno Torres, Benjami A1 - Völker, Christoph A1 - Munsch, Sarah Mandy A1 - Hanke, T. A1 - Kruschwitz, Sabine ED - Tosti, F. T1 - An Ontology-Based Approach to Enable Data-Driven Research in the Field of NDT in Civil Engineering N2 - Although measurement data from the civil engineering sector are an important basis for scientific analyses in the field of non-destructive testing (NDT), there is still no uniform representation of these data. An analysis of data sets across different test objects or test types is therefore associated with a high manual effort. Ontologies and the semantic web are technologies already used in numerous intelligent systems such as material cyberinfrastructures or research databases. This contribution demonstrates the application of these technologies to the case of the 1H nuclear magnetic resonance relaxometry, which is commonly used to characterize water content and porosity distri-bution in solids. The methodology implemented for this purpose was developed specifically to be applied to materials science (MS) tests. The aim of this paper is to analyze such a methodology from the perspective of data interoperability using ontologies. Three benefits are expected from this ap-proach to the study of the implementation of interoperability in the NDT domain: First, expanding knowledge of how the intrinsic characteristics of the NDT domain determine the application of semantic technologies. Second, to determine which aspects of such an implementation can be improved and in what ways. Finally, the baselines of future research in the field of data integration for NDT are drawn. KW - Ontology Engineering KW - Interoperability KW - Data-integration KW - NMR relaxometry KW - materials informatics PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529716 DO - https://doi.org/10.3390/rs13122426 SN - 2072-4292 N1 - Geburtsname von Munsch, Sarah Mandy: Nagel, S. M. - Birth name of Munsch, Sarah Mandy: Nagel, S. M. VL - 13 IS - 12 SP - 2426 PB - Multidisciplinary Digital Publishing Institute (MDPI) CY - Basel, Switzerland AN - OPUS4-52971 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Fabian T1 - An optimized HR-CS-GFMAS method for PFAS analysis N2 - HR-CS-GFMAS turned out to be a sensitive, fast and highly selective tool for fluorine determination. The method is based on the in situ formation of diatomic gallium-mono fluoride (GaF) at a temperature of 1550°C. GaF can be detected at 211.248 nm providing limits of quantificationin the low μg/L range. However, several species specific effects where observed when analyzing PFASs. T2 - 1st Summer School of the CRC 1349 Fluorine-Specific Interactions Fundamentals and Functions CY - Berlin, Germany DA - 28.08.2023 KW - PFAS KW - HR-CS-GFMAS KW - Fluorine PY - 2023 AN - OPUS4-58145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Fabian A1 - von der Au, Marcus A1 - Gehrenkemper, Lennart A1 - Meermann, Björn T1 - An optimized method for PFAS analysis using HR–CS–GFMAS via GaF detection N2 - The analysis of per- and polyfluoroalkyl substances (PFAS) via sum parameters like extractable organic fluorine (EOF) in combination with high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR–CS–GFMAS) is highly promising regarding fluorine sensitivity and selectivity. However, the HR–CS–GFMAS method includes several drying and heating steps which can lead to losses of volatile PFAS before the molecular formation step using e.g., GaF formation. Hence, the method leads to a strong discrimination of PFAS within the EOF depending on their physical/chemical properties and is therefore associated with reduced accuracy. To reduce this discrepancy and to indicate realistic PFAS pollution values, an optimization of the HR–CS–GFMAS method for PFAS analysis is needed. Hence, we determined fluorine response factors of several PFAS with different physical/chemical properties upon application of systematic optimization steps. We could therefore improve the method's sensitivity for PFAS analysis using a modifier drying pre-treatment step followed by a sequential injection of sample solutions. The highest improvement in sensitivity of volatile PFAS was shown upon addition of a Mg modifier during drying pre-treatment. Thereby, during optimization the relative standard deviation of fluorine response factors could be reduced from 55 % (initial method) to 27 % (optimized method) leading to a more accurate determination of organofluorine sum parameters. The method provides an instrumental LOD and LOQ of β(F) 1.71 μg/L and 5.13 μg/L, respectively. Further validation aimed to investigate several matrix effects with respect to water matrices. Here, substance-specific behavior was observed. For example, perfluorooctanoic acid (PFOA) which was used as calibrator, showed signal suppressions upon high chloride concentrations (>50 mg/L). Hence, a thorough separation of Cl from analytes during sample preparation is needed for accurate sum parameter analysis. KW - PFAS KW - GF-AAS KW - Method optimization PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610522 DO - https://doi.org/10.1016/j.talanta.2024.126811 VL - 281 SP - 1 EP - 11 PB - Elsevier B.V. AN - OPUS4-61052 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hallier, Dorothea C. T1 - An XPS study on X-ray radiation damage: Chemical changes to Gene-V Protein of Bacteriophage M13 N2 - X-ray photoelectron spectroscopy (XPS) is used to analyze the direct damage of ionizing radiation to a single-stranded DNA binding protein: Gene-V Protein (G5P). T2 - Science Day Uni Potsdam Institut für Biochemie und Biologie CY - Potsdam, Germany DA - 11.10.2022 KW - XPS KW - Radiaton damage KW - G5P GVP KW - Single-stranded DNA-binding protein KW - X-ray KW - DNA PY - 2022 AN - OPUS4-56541 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Silva, W. A1 - Zscherpel, Uwe A1 - Ewert, U. A1 - Lopes, R. T1 - Analysis of angular dependent spatial frequency response of Digital Coplanar Translational Laminography N2 - Digital Coplanar Translational Laminography (CTL) is a radiographic imaging technique that permits the visualization of structural details and discontinuities in the object of interest after 3D reconstruction from multiple projections. This technique becomes quite competitive regarding to computed tomography in situations of arrangements in which no complete rotation of the X-ray source - detector system around the object of interest is accessible or in cases where the part to be inspected has a high geometric asymmetry. The literature does not show many studies about image quality for different laminographic reconstructions and scan geometries. Different methodologies for measuring the Modulation Transfer Function (MTF) as a key image quality parameter for the aforementioned technique are applied. The MTF was measured using different approaches, presampled MTF or sampled MTF, both based on the Fourier Transform-Magnitude Spectrum or the square wave MTF using line pattern gauges. A sample known as Siemens Star with a converging line pattern was used to measure the circular square wave MTF. This circular MTF provides information on the direction dependent contrast transfer related to the measurement conditions, the reconstruction algorithms and the translational scan direction. For this purpose, several MTF measurements were performed in multiple angular directions. Beyond it, reconstructions were performed using different algorithms (Filtered Shifted Average) and an iterative one (MART – Multiplicative Algebraic Reconstruction Technique). Image quality analysis were done for both reconstruction methods. MART showed an image quality improvement for challenging conditions for laminographic arrangements, such as for a low number of projections (down to 25 for this study, considered as limited view, limited angle reconstruction). Additionally, a Gadolinium gauge with parallel line patterns within a range from 10 μm to 1000 μm was used to compare the square wave MTF with the sine MTFs, measured by the different techniques mentioned above. The results show that the MTF techniques presented are equivalent in this study. The results obtained for this Gadolinium plate showed a good agreement between MTF10% and SRb image measurements. The methodology presented here is used for the characterization of the frequency dependent spatial resolution of measurements obtained from different laminographic reconstruction techniques and scan geometries. Finally, from the acquisitions and reconstructions obtained with the Siemens Star, cross laminographic images were calculated in order to improve the direction dependent sensitivity. The results showed a better detectability for cross laminographic images in comparison to unidirectional coplanar translational laminographic images covering dead zones. KW - Laminography KW - Image quality KW - Modulation transfer function KW - Cross laminography KW - Reconstruction algorithms PY - 2021 DO - https://doi.org/10.1016/j.ndteint.2021.102546 SN - 0963-8695 VL - 124 SP - 1 EP - 13 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-53845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Urban, Klaus A1 - Ackerhans, C. A1 - Gorbushina, Anna T1 - Analysis of Carbon and Nitrogen from Atmospheric Sources by Bulk Deposition Sampling at various locations in Germany N2 - Atmospheric deposition of particulate matter is an important indicator of air pollution and a significant factor in material surface fouling. The elemental composition of this nutrient-containing dust depends largely on the exposure region and time as well as on climate. Therefore, in this paper we report an analysis of atmospheric pollutions with a self-made low-cost bulk deposition sampler directed at sampling deposition via air transport and rainfall. We used the device in diverse environments - thus comparing an urban region, an area surrounded by forest and an area mainly dominated by agriculture. The total organic carbon (TOC) and total nitrogen (TN) amounts were selected as indicator parameters and analyzed in a biweekly rhythm for three and a half and two years, respectively. The TOC value responded to particulate matter in the urban area, especially significant were the influences of the New Year's firework in urban and pollen in the rural forest area. In contrast, the TN value was more under the influence of the nitrogen emissions in the agriculture-dominated area. However, the TN value did not correlate with the NOx values in the urban area because the atmospheric nitrogen emissions in the city might originate from various emission sources. Summarizing, the TOC and TN values of the self-made low-cost bulk deposition sampler were in good agreement with environmental events of their immediate surrounding. Moreover, the selected containers and sampling procedures are universally applicable to monitor and analyze organic as well as inorganic parameters (e.g. metal ions) of atmospheric deposition. KW - Passive sampling KW - Biomonitoring KW - Air Analysis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609373 DO - https://doi.org/10.1016/j.envadv.2024.100583 SN - 2666-7657 VL - 17 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-60937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knoche, Lisa A1 - Lisec, Jan A1 - Koch, Matthias T1 - Analysis of electrochemical and liver microsomal transformation products of lasalocid by LC/HRMS N2 - Rationale: Lasalocid (LAS), an ionophore, is used in cattle and poultry farming as feed additive for its antibiotic and growth-promoting properties. Literature on transformation products (TP) resulting from LAS degradation is limited. So far, only hydroxylation is found to occur as the metabolic reaction during the LAS degradation. To investigate potential TPs of LAS, we used electrochemistry (EC) and liver microsome (LM) assays to synthesize TPs, which were identified using liquid chromatography high-resolution mass spectrometry (LC/HRMS). Methods: Electrochemically produced TPs were analyzed online by direct coupling of the electrochemical cell to the electrospray ionization (ESI) source of a Sciex Triple-TOF high resolution mass spectrometer. Then, EC-treated LAS solution was collected and analyzed offline using LC/HRMS to confirm stable TPs and improve their annotation with a chemical structure due to informative MS/MS spectra. In a complementary approach, TPs formed by rat and human microsomal incubation were investigated using LC/HRMS. The resulting data were used to investigate LAS modification reactions and elucidate the chemical structure of obtained TPs. Results: The online measurements identified a broad variety of TPs, resulting from modification reactions like (de-)hydrogenation, hydration, methylation, oxidation as well as adduct formation with methanol. We consistently observed different ion complexations of LAS and LAS-TPs (Na+; 2Na+ K+; NaNH4 +; KNH4 +). Two stable methylated EC-TPs were found, structurally annotated, and assigned to a likely modification reaction. Using LM incubation, seven TPs were formed, mostly by oxidation/hydroxylation. After the identification of LM-TPs as Na+-complexes, we identified LM-TPs as K+-complexes. Conclusion: We identified and characterized TPs of LAS using EC- and LM-based methods. Moreover, we found different ion complexes of LAS-based TPs. This knowledge, especially the different ion complexes, may help elucidate the metabolic and environmental degradation pathways of LAS. KW - Mass Spectrometry KW - Electrochemistry KW - ECR KW - Lasalocid KW - Ionophore KW - Transformation products PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-553919 DO - https://doi.org/10.1002/rcm.9349 VL - 36 IS - 18 SP - 1 EP - 10 PB - Wiley online library AN - OPUS4-55391 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Terborg, R. A1 - Boehm, S. A1 - Kim, K. J. T1 - Analysis of elemental composition of Fe1-xNix and Si1-xGex alloy thin films by electron probe microanalysis and micro-focus X-ray fluorescence N2 - The present study reports on results of analysis of the elemental composition of thin films by electron probe microanalysis with energy dispersive (ED-EPMA) X-ray spectrometry in conjunction with the dedicated thin-film analysis software package Stratagem and by X-ray fluorescence in its version with a micro-focus X-ray fluorescence (μ-XRF) source attached to a scanning electron microscope (SEM). Two thin-film systems have been analyzed: Fe1-xNix on silicon wafer and Si1-xGex on Al2O3 substrate, in both cases the layers being grown to a thickness of about 200 nm by ion beam sputter deposition. Samples of five different atomic fractions have been produced and analyzed for each thin-film system. Moreover, reference samples with certified elemental composition and thickness have been also available. This study is part of an interlaboratory comparison organized in the frame of standardization technical committee ISO/TC 201 “Surface chemical analysis.” Two laboratories have been analyzed by ED-EPMA (one laboratory standardless and one laboratory using both standardless and with standards variants) and one laboratory by μ-XRF (standardless and with standards). All the elemental compositions obtained with different methods are in very good agreement for the complete two sets of five samples each. KW - Thin films KW - Elemental composition KW - FeNi KW - SiGe KW - Electron probe microanalysis KW - X-ray Fluorescence PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509262 DO - https://doi.org/10.1002/sia.6834 SN - 0142-2421 VL - 52 IS - 12 SP - 929 EP - 932 PB - John Wiley & Sons Ltd AN - OPUS4-50926 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogel, Christian T1 - Analysis of fluorine/PFAS in battery black mass at HESEB N2 - Lithium iron phosphate (LiFePO4) batteries are a safe, cost-effective alternative to traditional lithium-ion batteries, but industrial-scale recycling is not yet available. The recycling process faces challenges, especially in purifying materials like lithium, phosphate, and iron, and managing fluorine contamination from fluoropolymers and salts (including PFAS). Fluorine K-edge XANES spectroscopy was used to analyze the chemical states of fluorine in the recycled materials for a safe reuse of elements and defluorination. T2 - SESAME – Germany Support and Networking Meeting CY - Hamburg, Germany DA - 30.06.2025 KW - Per- and polyfluoroalkyl substances (PFAS) KW - Battery PY - 2025 AN - OPUS4-63560 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stiegler, L. M. S. A1 - Wegner, Karl David A1 - Weigert, Florian A1 - Peukert, W. A1 - Resch-Genger, Ute A1 - Walter, J. T1 - Analysis of Giant-Shell CdSe/CdS Quantum Dots via Analytical Ultracentrifugation Combined with Spectrally Resolved Photoluminescence N2 - Knowledge of the structure–property relationships of functional nanomaterials, including, for example, their size- and composition-dependent photoluminescence (PL) and particle-to-particle variations, is crucial for their design and reproducibility. Herein, the Angstrom-resolution capability of an analytical ultracentrifuge combined with an in-line multiwavelength emission detection system (MWE-AUC) for measuring the sedimentation coefficient-resolved spectrally corrected PL spectra of dispersed nanoparticles is demonstrated. The capabilities of this technique are shown for giant-shell CdSe/CdS quantum dots (g-QDs) with a PL quantum yield (PL QY) close to unity capped with oleic acid and oleylamine ligands. The MWE-AUC PL measurements are calibrated and validated with certified fluorescence standards. The spectrally corrected and size-dependent PL spectra of the g-QDs derived from a single MWE-AUC experiment are then analyzed and compared with the results of single-particle spectroscopic studies, yielding the PL spectra, decay kinetics, and blinking behavior of individual g-QDs. This study underlines the vast potential of MWE-AUC with in-line optical detection for the characterization of advanced nanomaterials with a complex structure. KW - Quantum dots KW - Analytical ultracentrifugation KW - Photoluminescence KW - Advanced nanomaterial characterization KW - Calibrated fluorescence measurements KW - Reference materials PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624357 DO - https://doi.org/10.1002/smtd.202401700 SN - 2366-9608 SP - 1 EP - 7 PB - Wiley VHC-Verlag AN - OPUS4-62435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sarif, Raduan A1 - Tiebe, Carlo A1 - Herglotz, Christian T1 - Analysis of Methods for Predicting H2 Sensor Responses N2 - Hydrogen (H2) is crucial for replacing fossil fuels and achieving net-zero emissions, but its flammability and explosiveness pose safety challenges. Rapid H2 leak detection is essential for triggering emergency accidents. However, H2 sensor response is constrained by material properties and gas flow dynamics, causing response and detection delays. Our current study explores various available algorithms for H2 sensor response prediction from early responses with a small time window, accelerating leakage detection. Our findings identify the most efficient algorithms for real-time implementation, enhancing H2 safety systems. T2 - SMSI 2025 2025-05-06 - 2025-05-08 Nürnberg CY - Nuremberg, Germany DA - 06.05.2025 KW - H2 safety KW - Early H2 leakage detection KW - Prediction algorithms KW - Stable H2 value prediction PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640617 SN - 978-3-910600-06-5 DO - https://doi.org/10.5162/SMSI2025/C6.3 SP - 169 EP - 170 PB - AMA Verband für Sensorik und Messtechnik e.V. CY - Berlin AN - OPUS4-64061 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sarif, Raduan A1 - Tiebe, Carlo A1 - Herglotz, Christian T1 - Analysis of Methods for Predicting H2 Sensor Responses N2 - Hydrogen (H2) is crucial for replacing fossil fuels and achieving net-zero emissions, but its flammability and explosiveness pose safety challenges. Rapid H2 leak detection is essential for triggering emergency accidents. However, H2 sensor response is constrained by material properties and gas flow dynamics, causing response and detection delays. Our current study explores various available algorithms for H2 sensor response prediction from early responses with a small time window, accelerating leakage detection. Our findings identify the most efficient algorithms for real-time implementation, enhancing H2 safety systems. T2 - SMSI 2025 Conference – Sensor and Measurement Science International CY - Nuremberg, Germany DA - 06.05.2025 KW - H2 safety KW - Early H2 leakage detection KW - Prediction algorithms KW - Stable H2 value prediction PY - 2025 AN - OPUS4-64194 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Analysis of Particle Size Distribution for Bimodal Model Nanoparticles by Scanning Electron Microscopy N2 - The present study addresses the capability of measurement of relative particle number concentration by scanning electron microscopy for model bimodal silica and gold samples prepared in the frame of the European research project “nPSize - Improved traceability chain of nanoparticle size measurements” as candidate reference nanoparticles. T2 - Microscopy and Microanalysis 2020 CY - Online meeting DA - 03.08.2020 KW - Nanoparticles KW - Silica KW - Gold KW - Electron microscopy KW - Particle size distribution PY - 2020 AN - OPUS4-51112 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chakraborty, J. A1 - Wang, Xin A1 - Stolinski, M. T1 - Analysis of Sensitivity of Distance between Embedded Ultrasonic Sensors and Signal Processing on Damage Detectability in Concrete Structures N2 - Damage detection of reinforced concrete (RC) structures is becoming a more attractive domain due to the safety issues arising in the last few decades. The damage in concrete can be caused by excessive exploitation of the structure or environmental effects. The cracks in concrete can be detected by different nondestructive testing methods. However, the available methods used for this purpose have numerous limitations. The technologies available in the market nowadays have difficulties detecting slowly progressive, locally limited damage. In addition, some of These methods cannot be applied, especially in hard-to-reach areas in the superstructures. In order to avoid these deficiencies, an embedded ultrasonic methodology can be used to detect cracks in RC structures. In this study, the methodology of crack detection supported with the advanced Signal processing algorithm was proposed and verified on RC structures of various types, and cracks occurring between embedded sensors can be detected. Moreover, different pairs of ultrasonic sensors located in the considered structures are used for the analysis of the sensitivity of distance between them. It is shown that the ultrasonic sensors placed in the range of 1.5–2 m can detect cracks, even when the other methods failed to detect changes in the structure. The obtained results confirmed that diffuse ultrasonic sensor methodology is able to monitor real structures more effectively than traditional techniques. KW - Ultrasound KW - Coda wave interferometry KW - Structural health monitoring PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543624 DO - https://doi.org/10.3390/acoustics4010007 VL - 4 IS - 1 SP - 89 EP - 110 PB - MDPI CY - Basel, Schweiz AN - OPUS4-54362 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Oesch, Tyler T1 - Analysis of the porosity of alkali-sensitive aggregates for the assessment of microstructure-dependent solubility in the context of ASR N2 - Intensified Alkali-Silica Reaction (ASR) damage has occurred on German roadways in recent years, leading to requirements for compulsory pre-construction investigation of aggregate alkali sensitivity using concrete tests with external alkali supply. However, since these tests are time-consuming and cost-intensive, there is interest in replacing them with a solubility test on pure aggregate in 0.1 M KOH solution at 80°C with a defined NaCl content (1wt.-%). In this context, the influence of aggregate pore structure on SiO2 and Al2O3 solubility was investigated in this project. This paper compares the results of porosity studies with X-ray Computed Tomography (3D-CT) and the Brunauer-Emmett-Teller (BET) method on individual quarried and river gravel granules of both rhyolite and greywacke. For visualization and quantification of both externally accessible and fully enclosed surfaces of granules using X-ray 3D-CT, special software tools were developed. The results demonstrated that the river gravel granules had significantly larger externally accessible surfaces than the quarried granules. BET measurements on individual stones showed, as expected, that measured surfaces were about three orders of magnitude larger than those from the X-ray 3D-CT analyses due to the higher spatial resolution of BET. There was no apparent correlation between the X-ray 3D-CT and BET surface areas. Mercury porosimetry measurements indicate that this may be due to the presence of significant porosity below the spatial resolution of the X-ray 3D-CT. A comparison of SiO2 and Al2O3 solubility measurements with the X-ray 3D-CT and BET surface area data resulted only in weak, inconclusive correlations, indicating the need for further experimental investigation. T2 - Microdurability Webinar CY - Online meeting DA - 12.10.2020 KW - X-ray Computed Tomography (CT) KW - Brunauer-Emmett-Teller (BET) Method KW - Alkali-Silica Reaction (ASR) KW - Porosity KW - Solubility PY - 2020 AN - OPUS4-51429 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hülagü, Deniz A1 - Tobias, Charlie A1 - Gojani, Ardian A1 - Rurack, Knut A1 - Hodoroaba, Vasile-Dan T1 - Analysis of the profile roughness of core-shell microparticles by electron microscopy N2 - A particle roughness analysis tool, based on electron microscopy images (SEM and TEM). The influence of various parameters on the calculated roughness was also investigated: the setting of the proper threshold, accelerating voltage, etc. The samples were gradually tilted to extend imaging information of more than only one projection. Furthermore, the measurement uncertainty of the profile roughness of particles associated to various orientations was estimated. KW - Core-shell particles KW - Electron microscopy KW - Image processing KW - MamaLoCa KW - Particle Characterization KW - Roughness PY - 2021 DO - https://doi.org/10.1017/S1431927621007285 VL - 27 IS - Suppl. 1 SP - 2002 EP - 2004 PB - Cambridge University Press AN - OPUS4-53123 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hülagü, Deniz T1 - Analysis of the profile roughness of core-shell microparticles by electron microscopy N2 - A particle roughness analysis tool, based on electron microscopy (EM) images. The influence of various parameters on the calculated roughness was also investigated: the setting of the proper threshold, accelerating voltage, etc. The samples were gradually tilted to extend imaging information of more than only one projection. Furthermore, the measurement uncertainty of the profile roughness of particles associated to various orientations was estimated. T2 - Microscopy and Microanalysis 2021 CY - Online Meeting DA - 01.08.2021 KW - MamaLoCA KW - Particle characterization KW - Electron microscopy KW - Roughness KW - Core-shell particles KW - Image processing PY - 2021 AN - OPUS4-53069 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Analytical & Characterisation Excellence in nanomaterial risk assessment: A tiered approach N2 - The work packages of the EU H2020 project ACEnano are presented and their activities in standardization and guidance for regulators and SMEs. T2 - ISO/TC 229 Strategy meeting CY - Online meeting DA - 10.11.2020 KW - Nanomaterials KW - Standardization KW - Risk assessment PY - 2020 AN - OPUS4-51611 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg T1 - Analytical and Characterisation Excellence in nanomaterial risk assessment: A tiered approach Task2.5 N2 - The final results of Task 2.5 "Optimization of sample preparation for characterization of ENPs using TOF-SIMS under real-life conditions (a.) UfZ: polymer template; b.) BAM: pressing of pellets)" were presented. T2 - ACEnano General Meeting CY - Amsterdam, The Netherlands DA - 05.03.2020 KW - Nanoparticles KW - ToF-SIMS KW - Preparation PY - 2020 AN - OPUS4-50572 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Guerra, M.F. A1 - Martinón-Torres, M. A1 - Lemasson, Q. A1 - Moignard, B. A1 - Pacheco, C. A1 - Pichon, L. A1 - Macdonald, L. A1 - Hess, M. A1 - Tissot, I. ED - Guerra, M. F. ED - Martinón-Torres, M. ED - Quirke, S. T1 - Analytical approaches to Egyptian goldwork N2 - The structure and composition of ancient gold objects retain information about their long history of manufacture, from the exploitation of the ore to the finishing touches, as well as evidence of their use, deposition, and degradation. By developing an efficient analytical strategy, it is possible to retrieve that information. This chapter sets the necessary foundation 131to explore fully the analytical results presented in the following chapters of this volume. The techniques employed in the analyses of the Egyptian jewellery are described and the analytical parameters provided. For more established techniques, only brief introductions are presented, while more recent developments are presented in greater detail. KW - Gold KW - Synchrotron KW - D2XRF KW - Egypt PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586039 DO - https://doi.org/10.17863/CAM.99681 SP - 131 EP - 191 AN - OPUS4-58603 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogel, Christian T1 - Analytical Challenges for PFAS in Environmental Samples - Methods, Approaches and Applicability N2 - Per- and polyfluoroalkyl substances (PFAS) are anionic, cationic and zwitterionic synthetic products, in which the hydrogen atoms on the carbon skeleton of at least one carbon atom have been completely replaced by fluorine atoms and which include up to 1.7 M compounds, depending on the definition. As a result of continuous and prolific use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil, groundwater and surface water. Furthermore, because of the continuous contamination through PFAS containing commercial products, effluents and sewage sludge from WWTPs have been shown to be an important source of PFAS discharge into the aquatic environment. In the last few years, legacy PFAS (≥C4) have been found in various environments, including soil, water and wastewater, and their environmental pathways have been partly described. Several long-chain PFAS species, and their respective salts are considered as persistent organic pollutants by the United Nations Stockholm Convention. These pollutants have been linked to altered immune and thyroid function, liver disease, lipid and insulin dysregulation, kidney disease, adverse reproductive and developmental outcomes, and cancer. A significant shift in the chemical industry towards production of short (C4-C7) and ultrashort (C1-C3) alternatives was observed in response to recently intensified regulations and restrictions on the use of long-chain (≥C8) PFAS. PFAS analysis in environmental samples is currently mainly done by liquid chromatography tandem mass spectrometry (LC-MS/MS). This efficient method is conducted in a targeted fashion analyzing a small subset of PFAS. The US EPA method for analysis of PFAS using LC-MS/MS for example currently lists 40 PFAS (≥C4). However, to get a better overview of the amount of “total PFAS,” sum parameter methods like total oxidizable precursor (TOP) assay and methods based on combustion ion chromatography (CIC) are in development. CIC results in data regarding the sum of absorbable organic fluorine (AOF) or extractable organic fluorine (EOF), which can also quantify other organically bound fluorine compounds such as fluorinated pesticides and pharmaceutical. Moreover, non-target and suspect screening mass spectrometry can be used to identify novel emerging PFAS and partly unknown fluorinated compounds in environmental samples. Furthermore, to analyze ultrashort PFAS (C1-C3), supercritical fluid chromatography (SFC), hydrophilic interaction chromatography (HILIC) and gas chromatography-mass spectrometry (GC-MS) are available, but further research is needed to develop reliable and accurate methods to quantify several ultrashort PFAS in environmental samples. Additionally, for research purpose several spectroscopical methods like X-ray photoelectron spectroscopy (XPS), fluorine K-edge X-ray absorption near-edge structure (XANES)spectroscopy, particular induced gamma-ray emission (PIGE) spectroscopy and 19F nuclear magnetic resonance (NMR) spectroscopy are available. T2 - CleanUp 2022 CY - Adelaide, Australia DA - 11.09.2022 KW - PFAS KW - Combustion ion chromatography KW - XANES spectroscopy PY - 2022 AN - OPUS4-55741 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jaeger, Carsten A1 - Lintelmann, Jutta A1 - Franke, Raimo A1 - Artati, Anna A1 - Cecil, Alexander A1 - Broda, Frank A1 - Klawonn, Frank A1 - Erban, Alexander A1 - Kopka, Joachim A1 - Fuchs, Beate A1 - Sommer, Ulf A1 - Neumann-Schaal, Meina A1 - O'Connor, Gavin T1 - Analytical practices, use and needs of standard and reference materials in the German-speaking metabolomics community: results of an online survey N2 - Introduction Since the early 2000s, metabolomics has grown rapidly, becoming integral to fields like life sciences, health, and environmental research. This expansion has led to the formation of national and international societies, such as Germany’s DGMet, to tackle emerging challenges. One of DGMet’s goals is to improve measurement quality by assessing community needs for harmonization and standardization. A recent survey within the German-speaking community aimed to identify current practices and gaps in the use of chemical standards and reference materials, to guide future standardization efforts and collaborative initiatives. Methods An online survey was conducted between June 2023 and April 2024. The survey consisted of 38 key questions and was open to research institutions from Germany, Austria, and Switzerland. Results The survey was accessed by 68 laboratories, with 23 institutes providing complete or partial responses (34% response rate), which is comparable to rates reported in similar surveys within the metabolomics and lipidomics communities. Respondents were mainly experienced researchers from Germany, focusing mainly on health-related (“red”) metabolomics, as indicated by 78% of the respondents, followed by microbial (“grey”, 48%) and plant (“green”, 39%) metabolomics (multiple answers possible). The use of targeted methods was reported more frequently (91%) than that of non-targeted methods (78%), whereas metabolite fractions studied were equally split between polar, midpolar and lipid fractions (83% each). Human (74%), mouse (61%) and Arabidopsis (30%) were the most frequently studied organisms. Most participants used synthetic chemical standards for instrument qualification (83%), calibration (78%), and metabolite identification (74%), while matrix reference materials were mainly applied for quality control (52%) and method validation (44%). There was a strong demand for more standards, especially for metabolite identification and quantification, with cost being a major barrier, particularly for isotopically labelled standards and certified reference materials. Conclusions Valuable insights into the use of standards and reference materials within the German-speaking metabolomics community were obtained. Moving forward, the community should address critical gaps in metabolomics standardization. To achieve this, it must share its knowledge, articulate its needs clearly, and actively engage in joint efforts with national metrology institutes and international standardization initiatives. KW - Reference material KW - Chemical standard KW - Metabolomics KW - Mass spectrometry PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-647303 DO - https://doi.org/10.1007/s11306-025-02360-x VL - 21 IS - 6 SP - 1 EP - 11 PB - Springer-Nature CY - Heidelberg AN - OPUS4-64730 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fackeldey, K. A1 - Röhm, J. A1 - Niknejad, A. A1 - Chewle, Surahit A1 - Weber, M. T1 - Analyzing Raman spectral data without separabiliy assumption N2 - Raman spectroscopy is a well established tool for the analysis of vibration spectra, which then allow for the determination of individual substances in a chemical sample, or for their phase transitions. In the time-resolved-Raman-sprectroscopy the vibration spectra of a chemical sample are recorded sequentially over a time interval, such that conclusions for intermediate products (transients) can be drawn within a chemical process. The observed data-matrix M from a Raman spectroscopy can be regarded as a matrix product of two unknown matrices W and H, where the first is representing the contribution of the spectra and the latter represents the chemical spectra. One approach for obtaining W and H is the non-negative matrix factorization. We propose a novel approach, which does not need the commonly used separability assumption. The performance of this approach is shown on a real world chemical example. KW - Non-negative matrix factorization KW - NMF KW - Raman spectra KW - Separability condition KW - PCCA+ PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559051 DO - https://doi.org/10.1007/s10910-020-01201-7 SN - 1572-8897 VL - 59 SP - 575 EP - 596 PB - Springer Science + Business Media CY - Dordrecht AN - OPUS4-55905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Geißler, Daniel A1 - Nirmalananthan-Budau, Nithiya A1 - Scholtz, Lena A1 - Tavernaro, Isabella A1 - Resch-Genger, Ute T1 - Analyzing the surface of functional nanomaterials — how to quantify the total and derivatizable number of functional groups and ligands N2 - Functional nanomaterials (NM) of different size, shape, chemical composition, and surface chemistry are of increasing relevance for many key technologies of the twenty-first century. This includes polymer and silica or silica-coated nanoparticles (NP) with covalently bound surface groups, semiconductor quantum dots (QD), metal and metal oxide NP, and lanthanide-based NP with coordinatively or electrostatically bound ligands, as well as surface-coated nanostructures like micellar encapsulated NP. The surface chemistry can significantly affect the physicochemical properties of NM, their charge, their processability and performance, as well as their impact on human health and the environment. Thus, analytical methods for the characterization of NM surface chemistry regarding chemical identification, quantification, and accessibility of functional groups (FG) and surface ligands bearing such FG are of increasing importance for quality control of NM synthesis up to nanosafety. Here, we provide an overview of analytical methods for FG analysis and quantification with special emphasis on bioanalytically relevant FG broadly utilized for the covalent attachment of biomolecules like proteins, peptides, and oligonucleotides and address methodand material-related challenges and limitations. Analytical techniques reviewed include electrochemical titration methods, optical assays, nuclear magnetic resonance and vibrational spectroscopy, as well as X-ray based and thermal analysis methods, covering the last 5–10 years. Criteria for method classification and evaluation include the need for a signal-generating label, provision of either the total or derivatizable number of FG, need for expensive instrumentation, and suitability for process and production control during NM synthesis and functionalization. KW - Functional group quantification KW - Surface ligand KW - Nanomaterial KW - Optical detection KW - Electrochemical titration KW - Nanosafety (Safe-by-design) PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-533597 DO - https://doi.org/10.1007/s00604-021-04960-5 VL - 188 IS - 10 SP - 1 EP - 28 PB - Springer Nature AN - OPUS4-53359 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Liehr, Sascha T1 - ANNforPAT - Artificial Neural Networks for Process Analytical Technology N2 - This code accompanies the paper "Artificial neural networks for quantitative online NMR spectroscopy" published in Analytical and Bioanalytical Chemistry (2020). KW - Artificial neural networks KW - Automation KW - Online NMR spectroscopy KW - Process industry KW - Real-time process monitoring PY - 2020 UR - https://github.com/BAMresearch/ANNforPAT PB - GitHub CY - San Francisco AN - OPUS4-54481 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sprachmann, J. A1 - Wachsmuth, T. A1 - Bhosale, M. A1 - Burmeister, D. A1 - Smales, Glen Jacob A1 - Schmidt, M. A1 - Kochovski, Z. A1 - Grabicki, N. A1 - Wessling, R. A1 - List-Kratochvil, E. J. W. A1 - Esser, B. A1 - Dumele, O. T1 - Antiaromatic Covalent Organic Frameworks Based on Dibenzopentalenes N2 - Despite their inherent instability, 4n π systems have recently received significant attention due to their unique optical and electronic properties. In dibenzopentalene (DBP), benzanellation stabilizes the highly antiaromatic pentalene core, without compromising its amphoteric redox behavior or small HOMO−LUMO energy gap. However, incorporating such molecules in organic devices as discrete small molecules or amorphous polymers can limit the performance (e.g., due to solubility in the battery electrolyte solution or low internal surface area). Covalent organic frameworks (COFs), on the contrary, are highly ordered, porous, and crystalline materials that can provide a platform to align molecules with specific properties in a well-defined, ordered environment. We synthesized the first antiaromatic framework materials and obtained a series of three highly crystalline and porous COFs based on DBP. Potential applications of such antiaromatic bulk materials were explored: COF films show a conductivity of 4 × 10−8 S cm−1 upon doping and exhibit photoconductivity upon irradiation with visible light. Application as positive electrode materials in Li-organic batteries demonstrates a significant enhancement of performance when the antiaromaticity of the DBP unit in the COF is exploited in its redox activity with a discharge capacity of 26 mA h g−1 at a potential of 3.9 V vs. Li/Li+ . This work showcases antiaromaticity as a new design principle for functional framework materials. KW - SAXS KW - MOUSE KW - Covalent Organic Frameworks KW - Batteries PY - 2023 DO - https://doi.org/10.1021/jacs.2c10501 SP - 1 EP - 12 PB - ACS Publications AN - OPUS4-56958 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Devi, Sarita A1 - Riedel, Soraya A1 - Döring, Sarah A1 - Hiller, Lukas A1 - Kaliyaraj Selva Kumar, Archana A1 - Flemig, Sabine A1 - Singh, Chandan A1 - Konthur, Zoltán A1 - Hodoroaba, Vasile-Dan A1 - Schneider, Rudolf T1 - Antibodies Functionalized Magnetic Fe-Metal-Organic Framework Based Biosensor for Electrochemical Detection of Tetanus Neurotoxin N2 - This work presents a metal-organic framework (MOF)-integrated microfluidic flow-cell (MFC) based immunodetection of the tetanus toxoid (TT) using electrochemical technique for the first time. The magnetic property of Fe-MOF helped to hold them on the working electrode at detection zone of MFC surpassing the requirement of additional conjugation chemistry, whereas the conductive property was utilized to observe the change in signal efficiency in the presence of TT. The one-pot hydrothermal synthesis of a magnetic and conductive iron-based MOF (Fe-MOF) was performed using the Fe3 +/Fe2+ precursors as 1.2/1 mmol and dual ligands, i.e., tetrahydroxy-1,4-benzoquinone and 2-aminobenzene-1,4-dicarboxylic acid. The Fe-MOF was conjugated with L-phenylalanine (Fe-MOF/Phe) to increase its electric conductivity owing to the enhanced electron flow rate. The human monoclonal antibody SA13 against TT (anti-TT mAb) was conjugated on the Fe-MOF/Phe surface with the help of ethylenediamine (Fe-MOF/Phe/EDA/anti-TT mAb). The binding affinity of Fe-MOF/Phe/EDA/anti-TT mAb for the TT antigen was evaluated using cyclic voltammetry technique. The limit of detection of the Fe-MOF/Phe/EDA/anti-TT mAb-based biosensor for TT was 9.4 ng/ml in spiked buffer. This study shows the applicability of these Fe-MOFs in the detection of various other microbial toxins or other biomolecules. KW - Antikörper KW - Elektrochemischer Immunoassay KW - Molecular Organic Framework (MOF) KW - Microfluidics KW - Rekombinant PY - 2025 DO - https://doi.org/10.1016/j.snb.2025.137381 SN - 0925-4005 VL - 431 SP - 1 EP - 12 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-62673 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Munsch, Sarah Mandy A1 - Strangfeld, Christoph A1 - Kruschwitz, Sabine T1 - Application of 1H proton NMR relaxometry to building materials - A review N2 - Since nuclear magnetic resonance with focus on 1H protons is highly sensitive to pore filling fluids, it is nowadays often applied for the investigation of porous media. Mainly in materials research and especially in the field of non-destructive testing in civil engineering it is increasingly used. Scientific questions about and based on NMR meanwhile cover a broad spectrum. To give an overview, we have reviewed various studies dealing with the determination of moisture contents and parameters such as the pore-size distribution, surface relaxivity, porosity, etc. In some papers, the monitoring of moisture transport in connection with degradation processes or admixtures was the main objective. In other papers, NMR was used for pore space analysis or even applied on site to assess the state of conservation of cultural heritage. Building materials that have been investigated in the presented studies are for example cement, concrete, woods, sandstones etc. In this paper, short descriptions and the significant results of the reviewed articles are summarized and their measurement problems and discrepancies are pointed out. A special feature of this review article is the concise tabular compilation of determined 𝑇1 and 𝑇2 relaxation times, as well as of surface relaxivity values for various materials and components. Finally, relevant aspects are summed up and conclusions about the increasing potential of NMR relaxometry for investigations of porous building materials are drawn, followed by an outlook about future applications and the need for technical development. KW - NMR relaxometry KW - Building materials KW - Natural stones KW - Relaxation times KW - Surface relaxivities KW - Moisture KW - Pore space characterization PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521888 DO - https://doi.org/10.1016/j.jmro.2021.100012 N1 - Geburtsname von Munsch, Sarah Mandy: Nagel, S. M. - Birth name of Munsch, Sarah Mandy: Nagel, S. M. VL - 6-7 SP - 100012 PB - Elsevier Inc. CY - Amsterdam AN - OPUS4-52188 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vogel, Christian T1 - Application of Diffusive Gradients in Thin-films (DGT) and spectroscopic techniques to analyze phosphorus in soils N2 - A wide range of analytical methods are used to estimate the plant-availability of soil phosphorus (P). Previous investigations showed that analytical methods based on the Diffusive Gradients in Thin films (DGT) technique provide a very good correlations to the amount of bioavailable nutrients and pollutants in environmental samples (Davison 2016, Vogel et al. 2017). However, the DGT results do not identify which P compound of the soil has the high bioavailability. But there are various spectroscopic techniques (infrared, Raman, P K-edge and L-edge XANES and P NMR spectroscopy) available to characterize P species in soils. Therefore, spectroscopic investigation of DGT binding layers after deployment allow us to determine the specific compounds. Nutrients such as phosphorus and nitrogen are often, together with other elements, present as molecules in the environment. These ions are detectable and distinguishable by infrared, P K- and L-edge X-ray absorption near-edge structure (XANES) and NMR spectroscopy, respectively. Additionally, microspectroscopic techniques make it also possible to analyze P compounds on the DGT binding layer with a lateral resolution down to 1 μm2. Therefore, species of elements and compounds of e.g. a spatial soil segment (e.g. rhizosphere) can be mapped and analyzed, providing valuable insight to understand the dynamics of nutrients in the environment. T2 - SPP1685 Closing Conference: New Approaches to Ecosystem Nutrition - Phosphorus and Beyond CY - Freiburg, Germany DA - 25.10.2021 KW - Phosphorus KW - Diffusive gradients in thin-films (DGT) KW - Passive sampling PY - 2021 AN - OPUS4-53641 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grohmann, Maria A1 - Niederleithinger, Ernst A1 - Buske, S. A1 - Büttner, C. T1 - Application of Elastic P-SV Reverse Time Migration to Synthetic Ultrasonic Echo Data from Concrete Members N2 - The ultrasonic echo technique is frequently used in non-destructive testing (NDT) of concrete structures for thickness measurements, geometry determinations as well as localization of built-in components. To improve ultrasonic imaging of complex structures in concrete, we transferred a geophysical imaging technique, the reverse time migration (RTM), to NDT in civil engineering. In contrast to the conventionally used synthetic aperture focusing technique (SAFT) algorithms, RTM is a wavefield continuation method in time and uses the full wave equation. Thus, RTM can handle complicated wave propagations in any direction without dip limitation. In this paper, we focused on the application and evaluation of a two-dimensional (2D) elastic RTM algorithm considering compressional waves, vertically polarized shear waves, and Rayleigh waves. We tested the elastic RTM routine on synthetic ultrasonic echo data generated with a 2D concrete model consisting of several steps and circular air inclusions. As these complex structures can often be found in real-world NDT use cases, their imaging is especially important. By using elastic RTM, we were able to clearly reproduce vertical reflectors and lower edges of circular air voids inside our numerical concrete model. Such structures cannot be imaged with conventional SAFT algorithms. Furthermore, the used elastic RTM approach also yielded a better reconstruction of a horizontal reflector and upper boundaries of circular air inclusions. Our encouraging results demonstrate that elastic RTM has the potential to significantly improve the imaging of complex concrete structures and, thus, is a step forward for detailed, high-quality ultrasonic NDT in civil engineering. KW - Concrete KW - Ultrasound KW - Imaging KW - Reverse time migration KW - Elastic PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580680 DO - https://doi.org/10.1007/s10921-023-00962-w SN - 0195-9298 VL - 42 IS - 3 SP - 1 EP - 18 PB - Springer Nature AN - OPUS4-58068 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ermilova, Elena A1 - Weise, Matthias A1 - Hertwig, Andreas T1 - Application of imaging ellipsometry and white light interference microscopy for detection of defects in epitaxially grown 4H-SiC layers N2 - Critical defects, also known as device killers, in wide bandgap semiconductors significantly affect the performance of power electronic devices. We used the methods imaging ellipsometry (IE) and white light interference microscopy (WLIM) in a hybrid optical metrology study for fast and non-destructive detection, classification, and characterisation of defects in 4H–SiC homoepitaxial layers on 4H–SiC substrates. Ellipsometry measurement results are confirmed by WLIM. They can be successfully applied for wafer characterisation already during production of SiC epilayers and for subsequent industrial quality control. T2 - EOS Annual Meeting (EOSAM 2022) CY - Porto DA - 12.09.2022 KW - Imaging ellipsometry KW - White light interference microscopy KW - 4H–SiC KW - Defects PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574209 DO - https://doi.org/10.1051/jeos/2023018 SN - 1990-2573 VL - 19 IS - 1 SP - 1 EP - 8 PB - EDP Sciences AN - OPUS4-57420 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wilsch, Gerd T1 - Application of LIBS in civil engineering – status, trends and challenges N2 - The main application of LIBS in civil engineering is the detection of harmful ions in concrete, which can penetrate the component through the porous concrete structure. The advantages of LIBS over standard methods are the possibility of multi-element analysis, measurement speed, spatially resolved measurements, and minimal sample preparation. The spatially resolved measurements of LIBS allow the assessment of the heterogeneity of the concrete by measuring separately the chemical composition of the aggregates and the binder matrix. The latter is particularly relevant because the determined elemental distribution can be directly related to the binder matrix. This is not possible with standard methods, since the material is homogenized to powder during sample preparation stage and the determined concentration is thus related to the total mass. In addition to the use of LIBS for the specific analysis of individual harmful ions, LIBS can also be used to estimate the concrete composition and thus determine, for example, the type of cement used. Corresponding information are relevant for the estimation of the remaining service life and for the preparation of a maintenance concept. In recent years, LIBS has been increasingly used in civil engineering. Currently, however, it is primarily used in research institutions and only occasionally in building materials laboratories. Special commercial devices have also been developed, which greatly simplify the application due to the high degree of automation. Mobile LIBS systems allow on-site application. A central point, which limits the use of LIBS in the commercial sector, is the lack of norms and standards. Therefore, within the framework of a project funded by the German government, work has been carried out on the preparation of a leaflet on quantitative chlorine determination in concrete, which will be published this year. In interlaboratory comparisons the robustness and accuracy for the practical application was demonstrated. LIBS also has great potential in the recycling of construction waste in conjunction with hyperspectral sensors. This issue is currently being addressed in a national project. During the presentation, the state of the art of LIBS in civil engineering will be presented, next steps will be discussed, and future challenges will be outlined. T2 - XII international conference on laser induced breakdown spectroscopy (LIBS 2022) CY - Bari, Italy DA - 04.09.2022 KW - LIBS KW - Concrete KW - Chlorine KW - Civil engineering PY - 2022 AN - OPUS4-56535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völker, Tobias T1 - Application of LIBS to identify construction and demolition waste for circular economy N2 - Responsible treatment of the environment and resources is a key element of sustainability. The building and construction industry is one of the largest consumers of natural resources. Consequently, there is a particular need for regulations and technologies that help to create closed material cycles. From the technological point of view, such efforts are complicated by the growing material diversity and the amount of composites contained in present and future construction and demolition waste (CDW). Nowadays, simple but proven techniques like manual sorting are mainly used. However, this practice not only poses health risks and dangers to the staff performing the work, but also relies on merely obvious, visually striking differences. Automated, sensor-based sorting of these building materials could complement or replace this practice to improve processing speed, recycling rates, sorting quality, and prevailing health conditions. The preliminary results for the identification of a wide variety of building materials with LIBS are presented. T2 - XII Laser Induced Breakdown Spectroscopy (LIBS 2022) CY - Bari, Italy DA - 04.09.2022 KW - LIBS KW - Construction and demolition waste KW - Circular economy PY - 2022 AN - OPUS4-55679 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kjaervik, Marit A1 - Dietrich, P. M. A1 - Thissen, A. A1 - Radnik, Jörg A1 - Nefedov, A. A1 - Natzeck, C. A1 - Wöll, C. A1 - Unger, Wolfgang T1 - Application of near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) in an in-situ analysis of the stability of the surface-supported metal-organic framework HKUST-1 in water, methanol and pyridine atmospheres N2 - Surface-supported metal-organic frameworks HKUST-1 (Hong Kong University of Science and Technology) were used as a model system for a development of a near ambient pressure (NAP) XPS based approach to investigate interaction with atmospheres of water, methanol or pyridine at pressures ranging from 1 to 4 mbar. The films were grown on a gold substrate functionalized with a COOH-terminated self-assembled monolayer using liquidphase epitaxy in a step-by-step fashion. Measurement protocols were developed and optimised for different gases in order to obtain spectra of similar quality in terms of signal intensity, noise and shape. Peak shapes were found to depend on the efficiency of charge compensation. Reference measurements in argon proved to be a useful strategy not only for the evaluation of the Cu(II)-fraction in pristine samples, but also to identify the contributions by the respective gas atmosphere to the C 1s and O 1s photoelectron spectra. Reduced copper was found during the exposition of HKUST-1 to water vapour and pyridine, but this effect was not observed in case of methanol. Additionally, it was established that there are no changes in relative Cu(II) percentage with increasing exposure time. This indicates that saturation was reached already at the lowest time of gas exposure. A detailed elucidation of the mechanism of Cu(II) reduction to Cu(I) in HKUST-1 mediated by water and pyridine is part of ongoing work and not in the scope of the present paper. KW - HKUST-1 KW - Near-ambient pressure X-ray photoelectron spectroscopy KW - Metal-organic frameworks KW - Interaction with atmospheres KW - Water PY - 2021 DO - https://doi.org/10.1016/j.elspec.2020.147042 SN - 0368-2048 IS - 247 SP - 147042 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-52098 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grzelec, Małgorzata A1 - Haas, Sylvio A1 - Helman-Ważny, Agnieszka T1 - Application of scanning small-angle X-ray scattering in the identification of sheet formation techniques in historical papers N2 - Among writing substrates produced historically in different regions of the world, paper is one of the most complex materials. Its complexity results not only from a variety of highly processed ingredients, which can be used in its production, but also from a variety of methods in which these materials are combined to form the fibrillar network referred to as paper. While material identification methods are well established in the analysis of historical papers, the identification of manufacturing technologies is still an under-researched topic, that requires the development of appropriate methods and measurement protocols. This paper reports on the results of a research project aimed at the application of synchrotron scanning small angle X-ray scattering (SAXS) method in the characterization of paper structure, with emphasis on the assessment of fibrillar orientation as a marker characteristic for different, historical papermaking technologies. The main objective of this study consists of the development of a measurement protocol involving the SAXS technique complemented by other analytical methods in the characterization of the fibrous paper structure. KW - SAXS KW - Paper analysis KW - Papermaking technology KW - Fiber orientation PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-651594 DO - https://doi.org/10.1007/s00339-024-08157-4 SN - 0947-8396 VL - 131 IS - 1 SP - 1 EP - 16 PB - Springer Science and Business Media LLC AN - OPUS4-65159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lugovtsova, Yevgeniya T1 - Application of Temperature Compensation Strategies for Ultrasonic Guided Waves to 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 and impact on probability of detection (POD). This paper quantitatively describes two different methods to compensate the temperature effect, namely the optimal baseline selection (OBS) and the baseline signal stretch (BSS) extending their application to the case of a distributed sensor networks (DSN). This latter introduces a number of possible data to explore compensation strategies which do not necessarily returns univocal results. Hence, a decision framework is needed, which takes into consideration multiple ultrasonic time traces with different arrival times and amplitude. In detail, 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 a frequent value warning is introduced to find the more probable temperature with increasing reliability of the assessment. The same procedure is applied using the BSS algorithm. Finally, the use of both approaches is introduced, comparing the capability of the mixed algorithm to correctly sort temperature information from OBS and then apply the BSS combining the frequent value warning to have a unique correction all over the DSN. 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 combinations of results are available. Nonetheless, introducing a frequent value warning it is possible to increase the efficiency of the OBS and BSS approaches making use of fewer signal processing algorithms. These confirm that the performance of OBS quantitatively agrees with predictions. In addition, the possibility to combine BSS approached also demonstrates that the use of compensation strategies improves detectability and localization of damage even in a DSN. This result can be used to improve the SHM system reliability, with promising perspectives in increasing POD. T2 - ASME 2022 49th Annual Review of Progress in Quantitative Nondestructive Evaluation (QNDE2022) CY - San Diego, CA, USA DA - 25.07.2022 KW - Performance assessment KW - Elastic waves KW - Structural Health Monitoring PY - 2022 AN - OPUS4-55427 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst T1 - Applications of a Multi-Channel Ultrasound System for Assessing Large Concrete Structures N2 - Non-destructive testing (NDT) plays a vital role in the assessment of large concrete structures, where the detection of internal defects is particularly challenging due to size, material heterogeneity and complex geometries. In this study, the use of a multi-channel, large-aperture ultrasound system is demonstrated for improving the ultrasonic pulse-echo method for evaluating these large structures. The large aperture of the ultrasound system allows for broader coverage and enhanced sensitivity to internal features such as cracks, voids, and embedded components within the concrete. By capturing data from multiple channels simultaneously, the system improves both resolution and depth penetration. A weighted sum of the Kirchhoff migration is used to post-process the data, resulting in better visualisation and a more detailed interpretation of the internal condition of the structure. This approach is particularly effective for thick and complex materials where conventional methods face limitations. In addition to the pulse-echo method, time-of-flight (TOF) tomography is used to provide quantitative analysis of internal structures. Time-picking techniques allow for the precise mapping of anomalies within the material, offering insights into the condition of concrete with varying geometries and compositions. Together, these two methods: pulse-echo imaging with the large-aperture multichannel system and TOF tomography imaging, offer different possibilities for assessing the internal condition of large concrete structures. The pulse-echo technique focuses on providing detailed images of structural defects, while the TOF tomography provides quantitative data on internal features. This combined approach offers a comprehensive and reliable method for the assessment of large infrastructures. T2 - ISNT NDE 2024 CY - Chennai, India DA - 12.12.2024 KW - NDT-CE KW - concrete KW - ultrasound KW - imaging KW - Kirchhoff KW - tomography PY - 2024 AN - OPUS4-62204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Abad Andrade, Carlos Enrique T1 - Applications of atomic absorption spectrometry for lithium isotope analysis N2 - An alternative method for lithium isotope analysis by using high-resolution atomic absorption spectrometry (HR-CS-AAS) is proposed herein. This method is based on monitoring the isotope shift of approximately 15 pm for the electronic transition 22P←22S at around the wavelength of 670.8 nm, which can be measured by state-of-the-art HR-CS-AAS. Isotope analysis can be used for (i) the traceable determination of Li concentration and (ii) isotope amount ratio analysis based on a combination of HR-CS-AAS and spectral data analysis by machine learning (ML). In the first case, the Li spectra are described as the linear superposition of the contributions of the respective isotopes, each consisting of a spin-orbit doublet, which can be expressed as Gaussian components with constant spectral position and width and different relative intensity, reflecting the isotope ratio in the sample. Precision was further improved by using lanthanum as internal spectral standard. The procedure has been validated using human serum-certified reference materials. The results are metrologically comparable and compatible with the certified values. In the second case, for isotope amount ratio analysis, a scalable tree boosting ML algorithm (XGBoost) was employed and calibrated using a set of samples with 6Li isotope amount fractions ranging from 0.06 to 0.99 mol mol−1. The training ML model was validated with certified reference materials. The procedure was applied to the isotope amount ratio determination of a set of stock chemicals and a BAM candidate reference material NMC111 (LiNi1/3Mn1/3Co1/3O2), a Li-battery cathode material. These determinations were compared with those obtained by MC-ICP-MS and found to be metrologically comparable and compatible. The residual bias was −1.8‰, and the precision obtained ranged from 1.9‰ to 6.2‰. This precision was sufficient to resolve naturally occurring variations. The NMC111 cathode candidate reference material was analyzed using high-resolution continuum source atomic absorption spectrometry with and without matrix purification to assess its suitability for technical applications. The results obtained were metrologically compatible with each other. T2 - Colloquium Spectroscopicum Internationale XLII (CSI XLII) CY - Gijón, Spain DA - 30.05.2022 KW - Lithium KW - HR-CS-AAS KW - Chemometrics KW - Atomic spectrometry PY - 2022 AN - OPUS4-56498 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Applications of photoluminescence lifetime measurements in the life and material sciences N2 - Bioanalytical, diagnostic, and security applications require the fast and sensitive determination of a steadily increasing number of analytes or events in parallel in a broad variety of detection formats and increased sensitivities. This – flanked by recent technical advancements and the availability of simple to use, commercial time-resolved photoluminescence measuring devices at reasonable costs - calls for the exploitation of the species- and environment-specific photoluminescence parameter luminescence lifetime. In this context, time-resolved photoluminescence measurements of different classes of molecular and nanocrystalline emitter and luminescent particles in different time windows are presented and examples for applications such as lifetime multiplexing and barcoding in conjunction with fluorescence lifetime imaging microscopy (FLIM) and flow cytometry are given. T2 - Eingeladener Vortrag bei dem Workshop von Picoquant „Time-resolved fluorescence“ CY - Berlin, Germany DA - 17.11.2022 KW - Dye KW - Quantum dot KW - Upconversion nanocrystal KW - Luminescence KW - Quantitative spectroscopy KW - Photophysics KW - Quality assurance KW - Nano KW - Particle KW - Quantum yield KW - Lifetime KW - Standard KW - Reference material PY - 2022 AN - OPUS4-57048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stephan-Scherb, Christiane T1 - Applied Crystallography as a tool for a better understanding of Fundamental Questions of high temperature corrosion phenomena N2 - Corrosion Science Meets X-Rays, Neutrons and Electrons. The presentation gives an overview on current research activities applying in-situ X-ray diffraction and spectroscopy for a better understanding of fundamental mechanisms of high temperature corrosion. Additionally the knowledge gain by applying neutron powder diffraction and EBSD analysis is presented. T2 - Joint meeting of german and polish crystallographic association 2020 CY - Wroclaw, Poland DA - 24.02.2020 KW - Corrosion KW - Oxidation KW - In situ KW - Diffraction PY - 2020 AN - OPUS4-50483 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Talis, Torben T1 - Applying Time Series Extrinsic Regression to Parameter Estimation Problems for Dynamic Models - an Alternative for Gradient-Free Approaches? N2 - Time series analysis is a well-established field within the machine learning community, with two prominent applications being time-series forecasting, i.e., surrogate models, predicting the next time step for the systems outputs, and time-series classification, where complete timeseries are mapped to discrete labels, e.g. a sensor is either working or defective. Time-Series Extrinsic Regression (TSER), however, is a method for predicting continuous, time-invariant variables from a time series by learning the relation between these underlying parameters and the complete dynamic time series of the outputs without focusing on the recent states. E.g., it can be used to predict the heart rate based on an ECG signal. TSER as a research field was only established in 2021, but it is gaining traction ever since and it is used e.g. in the field of manufacturing technology to predict steel surface roughness from laser reflection measurements. It is applied, when there are no models available. Parameter Estimation (PE) is a common task in chemical engineering. It is used to adjust model parameters to better fit existing dynamic models to experimental time series data. This becomes more challenging in higher dimensions and for dynamic systems, where sensitivity and identifiability may change over time. There already exists a multitude of algorithms to solve the problem, including second-order methods that leverage information from Jacobian and Hessian matrices, as well as gradient-free optimization techniques, such as particle swarm optimization (PSO) or simulated annealing. However, with the growing establishment of machine learning (ML) in an increasing number of domains, the question arises as to whether, and if so, how, ML in general and TSER in particular can be employed to solve PE problems. This study marks the first application of TSER to PE problems. A comparative analysis is conducted between TSER and PSO, in terms of prediction accuracy, computational cost and data efficiency. We investigate, whether it is viable to use TSER, when there is a model available. Our methodology to regress model parameters via ML builds on the typical assumption, that a structurally correct and rigorous model, which can be simulated at low cost, is available. At the beginning, the boundaries of the parameter space are defined. This space is then sampled using Sobol sequences and the model is simulated. The resulting trajectories, along with their corresponding parameters, constitute the training data set. These trajectories are transformed through application of the “RandOm Convolutional Kernel Transform” method resulting in novel features, which are subsequently used to train the regressor model. This regressor returns predictions for the parameters. In a case study, the method is applied to predict the heat transfer and kinetic parameters of a batch reactor based on simulated data. However, real measurements are often not continuously available, but are taken only at rare, discrete points in time, and different variables are measured at different, asynchronous intervals. This is also mimicked in the synthetic training data, so the influence of heterogeneity on the results can be shown and over- or undersampling strategies are applied to counteract the effect. T2 - European Symposium on Computer Aided Process Engineering 35 CY - Gent, Belgium DA - 06.07.2025 KW - Time Series Extrinsic Regression KW - Parameter Estimation KW - Machine Learning PY - 2025 AN - OPUS4-65155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Küttenbaum, Stefan A1 - Maack, Stefan A1 - Taffe, A. T1 - Approach to the development of a model to quantify the quality of tendon localization in concrete using ultrasound N2 - Each engineering decision is based on a number of more or less accurate information. In assessment of existing structures, additional relevant information collected with on-site inspections facilitate better decisions. However, observed data basically represents the physical characteristic of interest with an uncertainty. This uncertainty is a measure of the inspection quality and can be quantified by expressing the measurement uncertainty. The internationally accepted rules for calculating measurement uncertainty are well established and can be applied straightforwardly in many practical cases. Nevertheless, the calculations require the occasionally time-consuming development of an individually suitable measurement model. This contribution attempts to emphasize proposals for modelling the non-destructive depth measurement of tendons in concrete using the ultrasonic echo technique. The proposed model can serve as guideline for the determination of the quality of the measured information in future comparable inspection scenarios. T2 - International Conference on Concrete Repair, Rehabilitation and Retrofitting (ICCRRR 2022) CY - Kapstadt, South Africa DA - 03.10.2022 KW - Reliability KW - Measurement Uncertainty KW - Non-Destructive Testing KW - Existing Concrete Structures PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559927 DO - https://doi.org/10.1051/matecconf/202236403007 SN - 2261-236X VL - 364 SP - 1 EP - 8 PB - EDP Sciences CY - Les Ulis, France AN - OPUS4-55992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - You, Yi A1 - Riedel, Jens T1 - Approaching phase-imaging through defocusing shadowgraphy for acoustic resonator diagnosis and the capability of direct index-of-refraction measurements N2 - The visualization of index-of-refraction (IoR) distribution is one of the common methods to investigate fluid flow or pressure fields. While schlieren and shadowgraphy imaging techniques are widely accepted, their inherent limitations often lead to difficulties in elucidating the IoR distribution and extracting the true IoR information from the resulting images. While sophisticated solutions exist, the IoR-gradient-to-image was achieved by purposely introducing a commonly avoided “defect” into the optical path of a conventional coincident schlieren/shadowgraphy setup; the defect is a combination of slight defocusing and the use of non-conjugate optical components. As such, the method presented in this work is referred to as defocusing shadowgraphy, or DF-shadowgraphy. While retaining the ease of a conventional schlieren/shadowgraphy geometry, this DF approach allows direct visualization of complicated resonant acoustic fields even without any data processing. For instance, the transient acoustic fields of a common linear acoustic resonator and a two-dimensional one were directly visualized without inversion. Moreover, the optical process involved in DF-shadowgraphy was investigated from a theoretical perspective. A numerical solution of the sophisticated impulse response function was obtained, which converts the phase distortion into intensity distributions. Based on this solution, the IoRs of various gas streams (e.g., CO2 and isopropanol vapor) were determined from single images. KW - Imaging Technique KW - Phase Imaging KW - Shadowgraphy KW - Schlieren Imaging PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537116 DO - https://doi.org/10.1063/5.0058334 SN - 1089-7623 VL - 92 IS - 10 SP - 103703 PB - AIP Publishing Group AN - OPUS4-53711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonnerot, Olivier T1 - Are X-rays safe for manuscripts’ materials? N2 - In the last decade, applications of X-rays to the study of manuscripts significantly spread in both diversity and extent. They range from writing material analysis, mostly with X-ray fluorescence (XRF), permitting non-invasive characterization of inks and pigments used, to the investigation of the origin of writing supports. In addition, XRF mapping has proved to be an invaluable tool for recovering erased text. Finally, computed-tomography (CT) has shown potential in virtually unrolling rolls, making text readable without using-damaging mechanical methods. Despite their growing use, little attention has been paid to the side effects of such analytical tools. We observed irreversible parchment colour changes during some experiments on dead-sea scrolls with synchrotron radiation sources. Furthermore, partial photo-reduction of iron under high intensity beam during X-ray absorption near edge structure spectroscopy (XANES) measurements of iron-gall ink on paper has been reported several times [5,6]. Such phenomena have mostly been overlooked so far, although there is an increasing awareness of the necessity to study them. We conducted experiments at the Deutsches Elektronen-Synchrotron (DESY) facilities to investigate X-ray induced structural alteration of paper and parchment to see whether the presence of absorption centres (ink and pigments) has an impact. In addition to better understanding degradation processes, we are aiming to define an appropriate methodology of analysis of manuscripts with a tolerable risk of damage. The first results concerning X-ray induced damage of cellulose materials have already been presented at the Synchrotron Radiation and Neutrons in Art and Archaeology (SR2A). We are focusing here on the results on parchment materials. T2 - Cultural and Natural Heritage Workshop CY - Grenoble, France DA - 22.01.2020 KW - X-rays KW - Manuscripts KW - Parchment KW - Synchrotron PY - 2020 AN - OPUS4-50305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fricke, F. A1 - Mahmood, S. A1 - Hoffmann, J. A1 - Brandalero, M. A1 - Liehr, Sascha A1 - Kern, Simon A1 - Meyer, Klas A1 - Kowarik, S. A1 - Westerdick, S. A1 - Maiwald, Michael A1 - Hübner, M. T1 - Artificial Intelligence for Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy N2 - Mass Spectrometry (MS) and Nuclear Magnetic Resonance Spectroscopy (NMR) are critical components of every industrial chemical process as they provide information on the concentrations of individual compounds and by-products. These processes are carried out manually and by a specialist, which takes a substantial amount of time and prevents their utilization for real-time closed-loop process control. This paper presents recent advances from two projects that use Artificial Neural Networks (ANNs) to address the challenges of automation and performance-efficient realizations of MS and NMR. In the first part, a complete toolchain has been developed to develop simulated spectra and train ANNs to identify compounds in MS. In the second part, a limited number of experimental NMR spectra have been augmented by simulated spectra to train an ANN with better prediction performance and speed than state-of-theart analysis. These results suggest that, in the context of the digital transformation of the process industry, we are now on the threshold of a possible strongly simplified use of MS and MRS and the accompanying data evaluation by machine-supported procedures, and can utilize both methods much wider for reaction and process monitoring or quality control. T2 - 2021 Design, Automation & Test in Europe Conference & Exhibition (DATE) CY - Grenoble, France DA - 01.02.2021 KW - Industry 4.0, KW - Cyber-physical systems KW - Artificial neural networks KW - Mass spectrometry KW - Nuclear magnetic resonance spectroscopy PY - 2021 DO - https://doi.org/10.23919/DATE51398.2021.9473958 SP - 615 EP - 620 PB - IEEE AN - OPUS4-55360 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fricke, F. A1 - Brandalero, M. A1 - Liehr, Sascha A1 - Kern, Simon A1 - Meyer, Klas A1 - Kowarik, Stefan A1 - Hierzegger, R. A1 - Westerdick, S. A1 - Maiwald, Michael A1 - Hübner, M. T1 - Artificial Intelligence for Mass Spectrometry and Nuclear Magnetic Resonance Spectroscopy Using a Novel Data Augmentation Method N2 - Mass Spectrometry (MS) and Nuclear Magnetic Resonance Spectroscopy (NMR) are valuable analytical and quality control methods for most industrial chemical processes as they provide information on the concentrations of individual compounds and by-products. These processes are traditionally carried out manually and by a specialist, which takes a substantial amount of time and prevents their utilization for real-time closed-loop process control. This paper presents recent advances from two projects that use Artificial Neural Networks (ANNs) to address the challenges of automation and performance-efficient realizations of MS and NMR. In the first part, a complete toolchain has been realized to develop simulated spectra and train ANNs to identify compounds in MS. In the second part, a limited number of experimental NMR spectra have been augmented by simulated spectra, to train an ANN with better prediction performance and speed than state-of-the-art analysis. These results suggest that, in the context of the digital transformation of the process industry, we are now on the threshold of a strongly simplified use of MS and MRS and the accompanying data evaluation by machine-supported procedures, and can utilize both methods much wider for reaction and process monitoring or quality control. KW - Industry 4.0 KW - Cyber-Physical Systems KW - Artificial Neural Networks KW - Mass Spectrometry KW - Nuclear Magnetic Resonance Spectroscopy KW - Modular Production PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539412 UR - https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=9638378 DO - https://doi.org/10.1109/TETC.2021.3131371 SN - 2168-6750 VL - 10 IS - 1 SP - 87 EP - 98 PB - IEEE AN - OPUS4-53941 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Artificial intelligence for spectroscopy examples from BAMline N2 - Various applications for artificial intelligence in the context of spectroscopy will be presented. in particular, examples from bamline will be featured. After a short introduction to synchrotron radiation, artificial intelligence algorithms for the quantification of X-ray fluorescence measurement are discussed. In the second example, information retrieval by natural language processing is reviewed. As a last example the reconstruction of measurements with the X-ray color camera and coded apertures is presented. T2 - Seminar Strahlenphysikalische Anwendungen in Technik und Medizin CY - ATi Wien, Austria DA - 22.01.2020 KW - Machine learning KW - Natural language processing KW - Neural networks KW - Synchrotron KW - BAMline PY - 2020 AN - OPUS4-51891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völker, Christoph T1 - Artificial intelligence in NDT (AI NDT) a networking workshop N2 - Data-driven research is considered the new paradigm in science. In this field, data is the new resource from which knowledge is extracted that is too complex for traditional methods. Several factors such as national funding and advances in information technology, are driving the development. In particular, the creation of databases and the analysis of data with artifical intelligence are playing an important role in establishing the new paradigm. However, there are numerous challenges that must be overcome to realize the full potential of data-driven methods. This talk sets the stage for the upcoming workshop by reviewing some of the historical developments and the current state of data-driven science in NDT and materials science. T2 - Workshop on Artificial Intelligence in NDT (AI-NDT) CY - Online meeting DA - 30.10.2020 KW - Data Science KW - Materials Informatics KW - NDT PY - 2020 AN - OPUS4-51812 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kern, Simon A1 - Liehr, Sascha A1 - Wander, Lukas A1 - Bornemann-Pfeiffer, Martin A1 - Müller, S. A1 - Maiwald, Michael A1 - Kowarik, Stefan T1 - Artificial neural networks for quantitative online NMR spectroscopy N2 - Industry 4.0 is all about interconnectivity, sensor-enhanced process control, and data-driven systems. Process analytical technology (PAT) such as online nuclear magnetic resonance (NMR) spectroscopy is gaining in importance, as it increasingly contributes to automation and digitalization in production. In many cases up to now, however, a classical evaluation of process data and their transformation into knowledge is not possible or not economical due to the insufficiently large datasets available. When developing an automated method applicable in process control, sometimes only the basic data of a limited number of batch tests from typical product and process development campaigns are available. However, these datasets are not large enough for training machine-supported procedures. In this work, to overcome this limitation, a new procedure was developed, which allows physically motivated multiplication of the available reference data in order to obtain a sufficiently large dataset for training machine learning algorithms. The underlying example chemical synthesis was measured and analyzed with both application-relevant low-field NMR and high-field NMR spectroscopy as reference method. Artificial neural networks (ANNs) have the potential to infer valuable process information already from relatively limited input data. However, in order to predict the concentration at complex conditions (many reactants and wide concentration ranges), larger ANNs and, therefore, a larger Training dataset are required. We demonstrate that a moderately complex problem with four reactants can be addressed using ANNs in combination with the presented PAT method (low-field NMR) and with the proposed approach to generate meaningful training data. KW - Online NMR spectroscopy KW - Real-time process monitoring KW - Artificial neural networks KW - Automation KW - Process industry PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507508 DO - https://doi.org/10.1007/s00216-020-02687-5 SN - 1618-2642 VL - 412 IS - 18 SP - 4447 EP - 4459 PB - Springer CY - Berlin AN - OPUS4-50750 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Assessing different types of silica networks for the complete protection of nir luminescent molecular rubies from oxygen quenching in air N2 - The application of emerging luminophores such as near-infrared (NIR) emissive earth-abundant chromium(III) (CrIII) complexes and triplet-triplet annihilation upconversion (TTA-UC) systems in air as optical reporters for bioimaging or photonic materials for energy conversion requires simple and efficient strategies for their complete protection from luminescence quenching by oxygen. Therefore, we explored the influence of sol-gel synthesis routes on the oxygen protection efficiency of the resulting core and core/shell silica nanoparticles (SiO2 NPs), utilizing the molecular ruby-type luminophores CrPF6 ([Cr(ddpd)2](PF6)3; ddpd = N,N’-dimethyl- N,N’-dipyridin-2-ylpyridin-2,6-diamine) and CrBF4 ([Cr(ddpd)2](BF4)3) with their oxygen-dependent, but polarity-, proticity-, viscosity-, and concentration-independent luminescence as optical probes for oxygen permeability. The sol-gel chemistry routes we assessed include the classical Stöber method and the underexplored larginine approach, which relies on the controlled hydrolysis of tetraethoxysilane (TEOS) in a biphasic cyclohexane/water system with the catalyst l-arginine. As demonstrated by luminescence measurements of air- and argon-saturated dispersions of CrPF6- and CrBF4-stained SiO2 NPs of different size and particle architecture, utilizing the luminescence decay kinetics of argon-saturated solutions of CrPF6 and CrBF4 in acetonitrile (ACN) as benchmarks, only SiO2 NPs or shells synthesized by the l-arginine approach provided complete oxygen protection of the CrIII complexes under ambient conditions. We ascribe the different oxygen shielding efficiencies of the silica networks explored to differences in density and surface chemistry of the resulting nanomaterials and coatings, leading to different oxygen permeabilities. Our l-arginine based silica encapsulation strategy can open the door for the efficient usage of oxygen-sensitive luminophores and TTA-UC systems as optical reporters and spectral shifters in air in the future. T2 - eMRS Strasbourg CY - Strasbourg, France DA - 26.05.2025 KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Quantum yield KW - NIR KW - Mechanism KW - Characterization KW - Electron microscopy KW - Silica KW - Oxygen sensing KW - Surface KW - Doping KW - Lifetime KW - Cr(III) complex PY - 2025 AN - OPUS4-63300 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sachse, René A1 - Pfüger, Mika A1 - Velasco-Vélez, Juan-Jesús A1 - Sahre, Mario A1 - Radnik, Jörg A1 - Bernicke, Michael A1 - Bernsmeier, Denis A1 - Hodoroaba, Vasile-Dan A1 - Krumrey, Michael A1 - Strasser, Peter A1 - Kraehnert, Ralph A1 - Hertwig, Andreas T1 - Assessing optical and electrical properties of highly active IrOx catalysts for the electrochemical oxygen evolution reaction via spectroscopic ellipsometry N2 - Efficient water electrolysis requires highly active electrodes. The activity of corresponding catalytic coatings strongly depends on material properties such as film thickness, crystallinity, electrical conductivity, and chemical surface speciation. Measuring these properties with high accuracy in vacuum-free and nondestructive methods facilitates the elucidation of structure−activity relationships in realistic environments. Here, we report a novel approach to analyze the optical and electrical properties of highly active oxygen evolution reaction (OER) catalysts via spectroscopic ellipsometry (SE). Using a series of differently calcined, mesoporous, templated iridium oxide films as an example, we assess the film thickness, porosity, electrical resistivity, electron concentration, electron mobility, and interband and intraband transition energies by modeling of the optical spectra. Independently performed analyses using scanning electron microscopy, energy-dispersive X-ray spectroscopy, ellipsometric porosimetry, X-ray reflectometry, and absorption spectroscopy indicate a high accuracy of the deduced material properties. A comparison of the derived analytical data from SE, resonant photoemission spectroscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy with activity measurements of the OER suggests that the intrinsic activity of iridium oxides scales with a shift of the Ir 5d t2g sub-level and an increase of p−d interband transition energies caused by a transition of μ1-OH to μ3-O species. KW - Spectroscopic ellipsometry KW - Electrocatalysis KW - Oxygen evolution reaction KW - Mesoporous iridium oxide films KW - Non-destructive ambient analysis KW - Intrinsic OER activity KW - Complementary methodology and metrology PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-516288 DO - https://doi.org/10.1021/acscatal.0c03800 SN - 2155-5435 VL - 10 IS - 23 SP - 14210 EP - 14223 PB - American Chemical Society AN - OPUS4-51628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kossatz, Philipp A1 - Mezhov, Alexander A1 - Andresen, Elina A1 - Prinz, Carsten A1 - Schmidt, Wolfram A1 - Resch-Genger, Ute T1 - Assessing the Applicability of Lanthanide-Based Upconverting Nanoparticles for Optically Monitoring Cement Hydration and Tagging Building Materials N2 - Chemically stable, lanthanide-based photon upconversion micro- and nanoparticles (UCNPs) with their characteristic multicolor emission bands in the ultraviolet (UV), visible (vis), near-infrared (NIR), and short-wave infrared (SWIR) arepromising optical reporters and barcoding tags. To assess the applicability of UCNPs for the monitoring of early stage cement hydration processes and as authentication tags for cementitious materials, we screened the evolution of the luminescence of Selfmade core-only NaYF4:Yb,Er UCNPs and commercial μm-sized Y2O2S:Yb,Er particles during the first stages of cement hydration, which largely determines the future properties of the hardened material. Parameters explored from the UCNP side included particle size, morphology, surface chemistry or coating, luminescence properties, and concentration in different cement mixtures. From the cement side, the influence of the mineral composition of the cement matrix was representatively examined for ordinary Portland cement (OPC) and its constituents tricalcium aluminate (C3A), tricalcium silicate (C3S), and gypsum at different water to cement ratios. Based on reflection and luminescence measurements, enabling online monitoring, which were complemented by XRD and isothermal heat-flow calorimetric measurements to determine whether the incorporation of these particles could impair cement hydration processes, well suited lanthanide particle reporters could be identified as well as application conditions. In addition, thereby the reporter influence on cement hydration kinetics could be minimized while still preserving a high level of information content. The best performance for the luminescence probing of changes during early stage cement hydration processes was observed for 25 nm-sized oleate (OA)-coated UCNPs added in a concentration of 0.1 wt %. Higher UCNP amounts of 1.0 wt % delayed cement hydration processes size- and surface coatingspecifically in the first 24 h. Subsequent luminescence stability screening studies performed over a period of about one year support the applicability of UCNPs as optical authentication tags for construction materials. KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Quantum yield KW - NIR KW - Mechanism KW - Characterization KW - XRD KW - Calorimetry KW - Advanced material KW - Cement KW - Monitoring KW - Surface KW - Size KW - Lifetime KW - Barcode KW - Lanthanide KW - Upconversion KW - Encoding KW - Method PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638318 DO - https://doi.org/10.1021/acsomega.5c02236 SN - 2470-1343 VL - 10 IS - 29 SP - 31587 EP - 31599 PB - ACS Publications CY - Washington, DC AN - OPUS4-63831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dhamo, Lorena A1 - Wegner, Karl David A1 - Würth, Christian A1 - Häusler, I. A1 - Hodoroaba, Vasile-Dan A1 - Resch-Genger, Ute T1 - Assessing the influence of microwave-assisted synthesis parameters and stabilizing ligands on the optical properties of AIS/ZnS quantum dots N2 - Luminescent semiconductor quantum dots (QDs) are frequently used in the life and material sciences as reporter for bioimaging studies and as active components in devices such as displays, light-emitting diodes, solar cells, and sensors. Increasing concerns regarding the use of toxic elements like cadmium and lead, and hazardous organic solvents during QD synthesis have meanwhile triggered the search for heavy-metal free QDs using green chemistry syntheses methods. Interesting candidates are ternary AgInS2 (AIS) QDs that exhibit broad photoluminescence (PL) bands, large effective Stokes shifts, high PL quantum yields (PL QYs), and long PL lifetimes, which are particularly beneficial for applications such as bioimaging, white light-emitting diodes, and solar concentrators. In addition, these nanomaterials can be prepared in high quality with a microwave-assisted (MW) synthesis in aqueous solution. The homogeneous heat diffusion and instant temperature rise of the MW synthesis enables a better control of QD nucleation and growth and thus increases the batch-to-batch reproducibility. In this study, we systematically explored the MW synthesis of AIS/ZnS QDs by varying parameters such as the order of reagent addition, precursor concentration, and type of stabilizing thiol ligand, and assessed their influence on the optical properties of the resulting AIS/ZnS QDs. Under optimized synthesis conditions, water-soluble AIS/ZnS QDs with a PL QY of 65% and excellent colloidal and long-term stability could be reproducible prepared. KW - Quantum dots KW - Microwave-assisted synthesis KW - AgInS KW - Aqueous synthesis PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567091 DO - https://doi.org/10.1038/s41598-022-25498-3 SN - 2045-2322 VL - 12 IS - 1 SP - 1 EP - 11 PB - Nature Publishing Group CY - London AN - OPUS4-56709 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Borges de Oliveira, F. A1 - Reuter, T. A1 - Plotzki, David A1 - Wohlgemuth, F. A1 - Bartscher, M. A1 - Bellon, Carsten A1 - Kasperl, S. T1 - Assessment of 2D-based tests for the qualification of simulation software for dXCT N2 - The interest in using computer simulations of dimensional x-ray computed tomography (dXCT) for various metrological purposes—such as measurement planning, performance prediction, performance optimisation and, finally, measurement uncertainty estimation—is increasing along with the ever-growing demand for more reliable measurements with dXCT. However, before a piece of simulation software can be used for tasks related to coordinate metrology, it has to be ensured that it is able to simulate physical laws, characteristic effects and basic CT system functionalities correctly and with sufficient accuracy. In short, the software must be qualified for dimensional metrology tasks. As one part of such a qualification process, a method is presented here for determining conformity intervals of 2D tests (projection-based tests) based on 3D tests (testing based on dimensional evaluations in a reconstructed volume) for the assessment of dXCT simulation software. The method consists of varying relevant parameter values in order to verify their influence on 3D measurement results. The results of the 3D tests with varied parameter values are then transferred to the quantities tested in the 2D tests and used as the basis for determining conformity intervals. Two approaches are applied for determining whether or not a variation of a parameter value is significant: (a) statistical and (b) heuristic. Two examples are presented, each based on simulated images, which show the application of the two different approaches for determining conformity intervals for the results of the 2D tests. KW - dXCT KW - X-ray computed tomography KW - Simulation PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573316 DO - https://doi.org/10.1088/1361-6501/acc1f9 VL - 34 IS - 6 SP - 1 EP - 12 PB - IOP Publishing AN - OPUS4-57331 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Möckel, J. A1 - Brangsch, J. A1 - Reimann, C. A1 - Kaufmann, Jan Ole A1 - Sack, I. A1 - Mangarova, D. B. A1 - Kader, A. A1 - Taupitz, M. A1 - Adams, L. C. A1 - Keller, S. A1 - Ludwig, A. A1 - Hamm, B. A1 - Botnar, R. M. A1 - Makowski, M. R. T1 - Assessment of Albumin ECM Accumulation and Inflammation as Novel In Vivo Diagnostic Targets for Multi-Target MR Imaging N2 - Atherosclerosis is a progressive inflammatory vascular disease characterized by endothelial dysfunction and plaque burden. Extracellular matrix (ECM)-associated plasma proteins play an important role in disease development. Our magnetic resonance imaging (MRI) study investigates the feasibility of using two different molecular MRI probes for the simultaneous assessment of ECM-associated intraplaque albumin deposits caused by endothelial damage and progressive inflammation in atherosclerosis. Male apolipoprotein E-deficient (ApoE-/-)-mice were fed a high-fat diet (HFD) for 2 or 4 months. Another ApoE-/--group was treated with pravastatin and received a HFD for 4 months. T1- and T2*-weighted MRI was performed before and after albumin-specific MRI probe (gadofosveset) administration and a macrophage-specific contrast agent (ferumoxytol). Thereafter, laser ablation inductively coupled plasma mass spectrometry and histology were performed. With advancing atherosclerosis, albumin-based MRI signal enhancement and ferumoxytol-induced signal loss areas in T2*-weighted MRI increased. Significant correlations between contrast-to-noise-ratio (CNR) post-gadofosveset and albumin stain (R2 = 0.78, p < 0.05), and signal loss areas in T2*-weighted MRI with Perls’ Prussian blue stain (R2 = 0.83, p < 0.05) were observed. No interference of ferumoxytol with gadofosveset enhancement was detectable. Pravastatin led to decreased inflammation and intraplaque albumin. Multi-target MRI combining ferumoxytol and gadofosveset is a promising method to improve diagnosis and treatment monitoring in atherosclerosis. KW - Magnetic resonance imaging KW - MRI KW - Imaging KW - Human serum albumin KW - Extracellular matrix KW - Macrophages KW - Contrast agent KW - Atherosclerotic plaques KW - Gadofosveset KW - Aneurysm PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-536725 DO - https://doi.org/10.3390/biology10100964 VL - 10 IS - 10 SP - 1 EP - 16 PB - MDPI CY - Basel AN - OPUS4-53672 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jurković, J. A1 - Kazlagić, Anera A1 - Sulejmanović, J. A1 - Smječanin, N. A1 - Karalija, E. A1 - Prkić, A. A1 - Nuhanović, M. A1 - Kolar, M. A1 - Albuquerque, A. T1 - Assessment of heavy metals bioaccumulation in Silver Birch (Betula pendula Roth) from an AMD active, abandoned gold mine waste N2 - Acid mine drainage (AMD) is generally outlined as one of the largest environmental concerns, characterized by very low pH value of mine waste, heavy metals and high sulphate content. This extremely hostile environment reduces plant ability to develop and grow. Present study focuses on a silver birch (Betula pendula Roth), a pioneer species that grows on an extremely hostile gold mine waste, to investigate the bioaccumulation of rare metals (thallium (Tl) and indium (In)), as well as nine other more common heavy metals (bismuth (Bi), cadmium (Cd), cobalt (Co), copper (Cu), lead (Pb), manganese (Mn), nickel (Ni), silver (Ag) and zinc (Zn)), and to asses phytoextraction and phytostabilization potential of silver birch. Additionally, parameters determining AMD process and overall contamination (pH, electrical conductivity (EC), sulphates (SO₄²⁻), arsenic (As), iron (Fe), oxidation–reduction potential (ORP), turbidity, dissolved oxygen (DO), total dissolved solids (TDS), acidity, hardness, X-ray diffraction (XRD) and radioactivity) were determined in mine waste and drainage water samples. To assess the heavy metals bioaccumulation and mine waste status, statistical geochemical indices were determined: bioaccumulation factor (BCF), pollution load index (PLI), geochemical abundance index (GAI) and exposure index (EI). The results show that silver birch bioaccumulates the essential elements Cu, Ni, Mn and Zn, and the nonessential elements Tl (average BCF = 24.99), In (average BC = 23.01) and Pb (average BCF = 0.84). Investigated mine waste was enriched by Bi, Ag and Cd according to positive values of GAI index. Present research provides a novel insight into bioaccumulation of nonessential heavy metals in silver birches who grow on the extremely hostile mine waste, and they exhibit significant phytoremediation potential. KW - Heavy metals KW - Acid mine drainage KW - Bioaccumulation KW - Silver birch KW - Thallium PY - 2023 DO - https://doi.org/10.1007/s10653-023-01774-7 SN - 1573-2983 SN - 0142-7245 VL - 45 SP - 9855 EP - 9873 PB - Springer Science and Business Media CY - Dordrecht AN - OPUS4-61835 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Moufid, M. A1 - Bouchikhi, B. A1 - Tiebe, Carlo A1 - Bartholmai, Matthias A1 - El Bari, N. T1 - Assessment of outdoor odor emissions from polluted sites using simultaneous thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS), electronic nose in conjunction with advanced multivariate statistical approaches N2 - Poor air quality, particularly in urban areas, causes various diseases and degrades living standards. Air Quality could be affected by emissions of odor, Volatile Organic Compounds (VOCs), and other gases. Therefore, assessment and monitoring of odorous air quality using sensitive, simple, rapid, accurate and portable tools is very important for public health. This study aimed to characterize odor emissions to detect malfunctions in facilities and to prevent air pollution and olfactory nuisance in the environment. A gas chromatographic method, in conjunction with sensorial analysis were performed for odorous air samples analysis collected from neighborhood of Meknes city (Morocco). Advanced multivariate statistical approaches, such as Principal Components Analysis (PCA), Discriminant Function Analysis (DFA), Support Vector Machines (SVMs), and Hierarchical Cluster Analysis (HCA), were used to describe samples similarities. The electronic nose (e-nose) data processing exhibits a satisfactory discrimination between the odorous air samples. Twenty-four VOCs with known molecular formulas were identified with Thermal Desorption-Gas Chromatography-Mass Spectrometry (TD-GC-MS). A validated Partial Least Square (PLS) model foresees good calibration between e-nose measurement and TD-GCMS analysis. The finding indicates that TD-GC–MS approach in conjunction with e-nose unit could be suitable tool for environmental measurement-based odor emissions. KW - Electronic nose KW - TD-GC-MS KW - PLS regression KW - Multivariate analysis KW - Outdoor odor emissions PY - 2021 DO - https://doi.org/10.1016/j.atmosenv.2021.118449 SN - 1352-2310 VL - 256 SP - 118449 PB - Elsevier Ltd. AN - OPUS4-52626 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - da Rocha, Morgana A1 - Chaves, Eduardo T1 - Assessment of Pd Nanoparticles as Chemical Modifiers and Preconcentration Agents for Cd Determination in River Water by HR-CS GFAAS N2 - Cadmium is a heavy metal that can be hazardous to environmental and human health, even in trace levels.[1] In this way, the extraction and/or preconcentration of this element from environmental samples, such as river water, is important to obtain information about the composition and monitoring of potential contamination.[2] High-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS) is widely used for Cd determination. However, the determination of this element at trace-level can be challenging, especially in complex matrices. Thus, nanoparticles (NPs) can be used as an alternative for the extraction and preconcentration of Cd in environmental samples, minimizing the potential interferences and improving the method´s limit of detection (LOD). Considering that Pd is also widely used as a “universal” chemical modifier, this project aims todevelop PdNPs capped with 3-mercaptopropionic acid (MPA) to assess its potential as a chemical modifier and preconcentration agent for Cd determination by HR-CS GF AAS in river water. In this way, the synthesis of PdNPs was performed in an aqueous medium by using ascorbic acid as a reducing agent. The characterization of PdNPs was performed by checking the size via dynamic light scattering (DLS), transmission electron microscopy (TEM), and inductively coupled plasma mass spectrometer in single particle mode (spICP-MS), where the median size was 56 ± 14 nm. The temperature program of HR-CS GFAAS was optimized for river water under three conditions: using Pd(NO3)2/Mg2+ (0.01%/0.5% m/v) as a chemical modifier (condition A), using Pd NPs as a chemical modifier (condition B), and without chemical modifiers (condition C). The pyrolysis and atomization temperatures for condition A were 900 and 1900 ºC, for condition B were 700 ºC and 1900 ºC, and for condition C were 500 and 1900ºC, respectively. Besides the temperature of pyrolysis for the universal chemical modifier being higher than that of PdNPs, using the PdNPs, the absorbance is significantly greater, according to the t-test for pairs, at a 95% confidence level. In addition, the evaluation of the preconcentration property of the PdNP was performed by adding 1 µg L-1 of Cd2+ in buffer pH 4 in two systems: one with and the other without PdNPs. After 1 h of stirring, both systems were centrifuged at 3600 rpm for 10 min, and the absorbance in HR-CS GFAAS for Cd in both supernatants was evaluated. According to ANOVA from the t-test, at a 95% confidence level, there was a significant difference in the absorbance, indicating that Cd is interacting with the PdNPs. A multifactorial planning 2k, where k is the number of parameters of the extraction, which was time of extraction (10; 35; 60 min), Volume of Pd NPs (100; 300; 500 µL), pH (3; 5; 7), was used to evaluate the parameters with significant influence in the preconcentration of Cd2+. According to ANOVA, with 95% confidence, there is no lack of fit, and the parameters volume of PdNP and pH significantly influenced the response. In this way, the Doehlert methodology surface will be applied to both significant parameters. The goal is to achieve optimal conditions that increase the extraction efficiency of Cd2+ from environmental samples. The results indicate that the developed material is promising to use as a chemical modifier and for the preconcentration of Cd2+ in environmental samples. T2 - 17th Rio Symposium on Atomic Spectrometry (RSAS 2025) CY - Sao Pedro, Brazil DA - 12.11.2025 KW - Pd Nanoparticles KW - HR-CS GFAAS KW - Cadmium Ion Sensing KW - Particle Characterization KW - Particle Surface PY - 2025 AN - OPUS4-64997 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Keller, S. A1 - Borde, T. A1 - Brangsch, J. A1 - Reimann, C. A1 - Kader, A. A1 - Schulze, D. A1 - Buchholz, R. A1 - Kaufmann, Jan Ole A1 - Karst, U. A1 - Schellenberger, E. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Assessment of the hepatic tumor extracellular matrix using elastin‑specific molecular magnetic resonance imaging in an experimental rabbit cancer model N2 - To investigate the imaging performance of an elastin-specific molecular magnetic resonance imaging (MRI) probe with respect to the extracellular matrix (ECM) in an experimental hepatic cancer model. Twelve rabbits with hepatic VX2 tumors were examined using 3 T MRI 14, 21, and 28 days after tumor implantation for two subsequent days (gadobutrol, day 1; elastin-specific probe, day 2). The relative enhancement (RE) of segmented tumor regions (central and margin) and the peritumoral matrix was calculated using pre-contrast and delayed-phase T1w sequences. MRI measurements were correlated to histopathology and element-specific and spatially resolved mass spectrometry (MS). Mixed-model analysis was performed to assess the performance of the elastin-specific probe. In comparison to gadobutrol, the elastin probe showed significantly stronger RE, which was pronounced in the tumor margin (day 14–28: P ≤ 0.007). In addition, the elastin probe was superior in discriminating between tumor regions (χ2(4) = 65.87; P < 0.001). MRI-based measurements of the elastin probe significantly correlated with the ex vivo elastinstain (R = .84; P <0 .001) and absolute gadolinium concentrations (ICP-MS: R = .73, P <0 .01). LA-ICP-MS imaging confirmed the colocalization of the elastin-specific probe with elastic fibers. Elastin-specific molecular MRI is superior to non-specific gadolinium-based contrast agents in imaging the ECM of hepatic tumors and the peritumoral tissue. KW - Elastin-specific molecular agent KW - Extracellular matrix KW - Hepatocellular carcinoma KW - Inductively coupled plasma mass spectroscopy KW - Laser ablation-inductively coupled plasma-mass spectrometry KW - Magnetic resonance imaging KW - MR imaging KW - ESMA KW - Gadolinium PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517360 DO - https://doi.org/10.1038/s41598-020-77624-8 VL - 10 IS - 1 SP - 20785 PB - Nature AN - OPUS4-51736 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Biesen, L. A1 - Krenzer, J. A1 - Nirmalananthan-Budau, Nithiya A1 - Resch-Genger, Ute A1 - Müller, Th. J. J. T1 - Asymmetrically bridged aroyl-S,N-ketene acetalbased multichromophores with aggregationinduced tunable emission N2 - Asymmetrically bridged aroyl-S,N-ketene acetals and aroyl-S,N-ketene acetal multichromophores can be readily synthesized in consecutive three-, four-, or five-component syntheses in good to excellent yields by several successive Suzuki-couplings of aroyl-S,N-ketene acetals and bis(boronic)acid esters. Different aroyl-S,N-ketene acetals as well as linker molecules yield a library of 23 multichromophores with substitution and linker pattern-tunable emission properties. This allows control of different communication pathways between the chromophores and of aggregation-induced emission (AIE) and energy transfer (ET) properties, providing elaborate aggregation-based fluorescence switches. KW - Dye KW - Aggregation KW - Aggregation induced emission KW - Signal enhancement KW - Energy transfer KW - Switch KW - Sensor KW - Quantum yield KW - Lifetime KW - Photophysics KW - Sythesis KW - Nanaoparticle PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-550719 DO - https://doi.org/10.1039/d2sc00415a VL - 13 SP - 5374 EP - 5381 PB - Royal Society of Chemistry AN - OPUS4-55071 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Morcillo, Dalia T1 - Atomic absorption spectrometry with machine learning as a tool for lithium isotope analysis N2 - The general interest in the implementation of renewable energies, particularly in the development of lithium-ion batteries, makes lithium a key element to be analyzed. We are working to develop this tool to determine if the isotopic effect of lithium has an impact on battery aging. T2 - SALSA Konferenz CY - Berlin, Germany DA - 16.09.2021 KW - Atomic absorption spectrometry KW - Battery KW - Machine learning KW - Lithium KW - Isotope PY - 2021 AN - OPUS4-53693 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Morcillo, Dalia T1 - Atomic absorption spectroscopy and machine learning for lithium isotopic study N2 - The isotopic analysis of lithium is also relevant to the study of geological phenomena.1 In this work we propose improvements to the method for the isotopic analysis of lithium using a high-resolution continuum source atomic absorption spectrometer (HR-CS-AAS) coupled to a double echelle modular spectrometer (DEMON). 2 This tool for isotopic ratio determination is based on monitoring the isotopic components of lithium by their spin-orbit coupling and its isotopic shift of about 15 pm for the 22P←2 2S electronic transition around 670.788 nm. The data analysis was carried out by using a decision-tree-based ensemble machine learning (ML) algorithm. For the training of the algorithm (XGBoost), a set of samples with 6Li isotope amount fractions ranging from 0.06 to 0.99 mol-1 was used. Subsequently, the procedure was validated of a set of stock chemicals (Li2CO3, LiNO3, LiCl and LiOH) and a BAM candidate reference material, the cathode material LiNi1/3Mn1/3Co1/3O2 (NMC111). Finally, the ML model was applied to the set of geological samples, previously digested, for the determination of their isotope ratio. The optical resolution was improved from 140,000 to 790,000 to better deconvolution the lithium isotopic components in the atomic spectrum. And the method was compared with multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The results are metrologically comparable. T2 - Colloquium Spectroscopicum Internationale XLII (CSI XLII) CY - Gijón, Spain DA - 30.05.2022 KW - Lithium isotope KW - Atomic absorption spectroscopy PY - 2022 AN - OPUS4-56357 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Li, Xunyu T1 - Atomic Isotope Analysis of Lithium with Spatial Heterodyne Spectrometry and Lineshape Recovery through Deconvolution N2 - A spatial heterodyne spectrometer (SHS) was combined with a reduced-pressure glow discharge to demonstrate the analytical utilization of high resolving-power spectral analysis for atomic isotopes. In the experimental illustrations, we will demonstrate the spectra for the lithium isotope ratio through the D-lines featuring 6Li and 7Li. The SHS utilized in our setup boasts single-digit picometer resolution, enabling the precise discrimination of three separate spectral bands in real-time. To further enhance the spectral quality and improve quantification accuracy, we established an innovative approach to recover the natural lineshape, avoiding interferences from the instrumental function that broadens fine features. By understanding the inherent characteristics of an SHS interferogram and leveraging computational capabilities, we will demonstrate the direct extraction of the numerical presentation of the instrumental function from an SHS interferogram; this instrumental function was used for spectral data processing that enables significant improvements in spectral resolution through deconvolution algorithms. The resulting high-quality spectra enabled precise quantitative determination of lithium concentrations and isotope ratios. We aim to showcase the procedures involved in fine-tuning an SHS platform, along with software design strategy to track real-time spectral variations. Meanwhile, the concept of the lineshape recovery through deconvolution will also be discussed. Furthermore, atomic lithium spectra featuring various isotope compositions will be presented to highlight the potential of SHS in real-life applications. T2 - SCIX 2024 Conference CY - Raleigh, NC, USA DA - 20.10.2024 KW - Spatial Heterodyne Spectrometry KW - High-Resolution Spectrometry KW - Isotopic Analysis KW - Line Shape Recovery KW - Instrumental Function PY - 2024 AN - OPUS4-62138 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Unger, Wolfgang A1 - Wirth, Thomas A1 - Hodoroaba, Vasile-Dan ED - Hodoroaba, Vasile-Dan ED - Unger, Wolfgang ED - Shard, A. G. T1 - Auger electron spectroscopy N2 - An introduction in the application of Auger Electron Spectroscopy to surface chemical analysis of nanoparticles is given. Auger Electron Spectroscopy is a mature method in the field of surface chemical analysis. The chapter addresses the physical basis of the method, the principal design of recent instruments together with modes of operation and options for the presentation of spectra, as well as different approaches for qualitative (including identification of chemical species) and quantitative surface analysis of elements. An application paragraph on surface chemical analysis of nanoparticles by AES or SAM introduces the different measurement approaches and sample preparation strategies applied by analysts. The analysis of nanoparticle ensembles, the so-called selected point analysis where a narrow primary electron beam is centered on an individual nanoparticle, and chemical mapping of individual nanoparticles (or a line scan across) are addressed. Existing literature is reviewed and informative case studies presented. Limitations and pitfalls in the application of AES in surface chemical analysis of nanoparticles are also addressed. KW - Auger Electron Spectroscopy KW - Surface chemical analysis KW - Imaging surface chemical analysis KW - Nanoparticles KW - Nanotechnology PY - 2020 SN - 978-0-12-814182-3 DO - https://doi.org/10.1016/B978-0-12-814182-3.00020-1 SP - 373 EP - 395 PB - Elsevier CY - Amsterdam AN - OPUS4-50119 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rabin, Ira T1 - Authentic vs. inauthentic Dead Sea Scrolls from the point of view of material analysis N2 - The paper seeks to illuminate the problem of identifying forgeries among the Dead Sea Scrolls from the point of view of material analysis. It will present the sum of our technical knowledge of the skin-based material of the Dead Sea Scrolls, which includes the original treatment of the skins and the resulting typology as well as degradation effects due to their sojourn in caves and post-discovery interventions. We will try then to list the characteristic properties that must be found in the authentic material. We will supplement the presentation with a short description of the relevant methods of material analysis and their contribution to the secure identification of inauthentic Dead Sea Scrolls. T2 - Annual Meeting of the Siciety of Biblical Literature CY - Denver, CO, USA DA - 19.11.2022 KW - Dear Sea Scrolls KW - Forgery PY - 2022 AN - OPUS4-61196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rühle, Bastian A1 - Hodoroaba, Vasile-Dan T1 - Automatic Image Segmentation and Analysis using Neural Networks N2 - We present a workflow for obtaining fully trained artificial neural networks that can perform automatic particle segmentations of agglomerated, non-spherical nanoparticles from electron microscopy images “from scratch”, without the need for large training data sets of manually annotated images. This is achieved by using unsupervised learning for most of the training dataset generation, making heavy use of generative adversarial networks and especially unpaired image-to-image translation via cycle-consistent adversarial networks. The whole process only requires about 15 minutes of hands-on time by a user and can typically be finished within less than 12 hours when training on a single graphics card (GPU). After training, SEM image analysis can be carried out by the artificial neural network within seconds, and the segmented images can be used for automatically extracting and calculating various other particle size and shape descriptors. T2 - Machine Learning Workshop CY - Online Meeting DA - 18.03.2021 KW - Electron Microscopy KW - Neural Networks KW - Artificial Intelligence KW - Image Segmentation KW - Automated Image Analysis PY - 2021 AN - OPUS4-52304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barzegar, M. A1 - Lugovtsova, Yevgeniya A1 - Bulling, Jannis A1 - Mishurova, Tatiana A1 - Pasadas, D. A1 - Ribeiro, A. A1 - Ramos, H. T1 - Automatic improved-resolution imaging of composite adhesive joints using time-frequency-wavenumber filtering applied to ultrasonic guided wavefields N2 - This paper presents an automatic damage imaging technique by employing a signal processing approach based on applying hierarchically clustered filters across different domains. The technique involves time-frequency-wavenumber filter banks which are applied sequentially to ultrasonic guided wave (UGW) data. The study is conducted for a single lap joint composite specimen with a special focus on small voids which were formed due to manual adhesive component mixing. UGW data are acquired with a 3D Scanning Laser Doppler Vibrometer (LDV) over the scan area of the bonded plate. UGWs are excited at the central frequency of 100 kHz by a single piezoelectric transducer mounted on the surface of the single plate. Within each domain of time, frequency, and wavenumber, four filters are designed which results in 64 distinct filtered wavefields. From each filtered wavefield, an image is obtained by using root-mean-square (RMS) calculation of the signals. The obtained results are then combined to create a final, improved-resolution image of the scan area. The final image is compared to the image obtained through RMS calculation of full wavefield with interpolation through Delaunay triangulation and the image obtained by X-ray radiography. The results show that the smallest void that could be detected has a diameter of 2.14 mm. T2 - 2023 IEEE International Ultrasonics Symposium (IUS) CY - Montreal, QC, Canada DA - 03.09.2023 KW - Adhesive joints KW - Ultrasonic guided waves KW - Laser Doppler vibrometer KW - Damage imaging KW - Non-destructive testing KW - Porosity analysis PY - 2023 DO - https://doi.org/10.1109/IUS51837.2023.10307423 SP - 1 EP - 4 PB - IEEE AN - OPUS4-58795 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 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Luch, A. A1 - Sogne, V. A1 - Maier, F. A1 - Burr, L. A1 - Schmid, D. A1 - Yoon, T.-H. A1 - Petters, R. A1 - Briffa, S.M. A1 - Valsami-Jones, E. T1 - Automation and Standardization—A Coupled Approach Towards Reproducible Sample Preparation Protocols for Nanomaterial Analysis N2 - Whereas the characterization of nanomaterials using different analytical techniques is often highly automated and standardized, the sample preparation that precedes it causes a bottleneck in nanomaterial analysis as it is performed manually. Usually, this pretreatment depends on the skills and experience of the analysts. Furthermore, adequate reporting of the sample preparation is often missing. In this overview, some solutions for techniques widely used in nano-analytics to overcome this problem are discussed. Two examples of sample preparation optimization by au-tomation are presented, which demonstrate that this approach is leading to increased analytical confidence. Our first example is motivated by the need to exclude human bias and focuses on the development of automation in sample introduction. To this end, a robotic system has been de-veloped, which can prepare stable and homogeneous nanomaterial suspensions amenable to a variety of well-established analytical methods, such as dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), field-flow fractionation (FFF) or single-particle inductively coupled mass spectrometry (sp-ICP-MS). Our second example addresses biological samples, such as cells exposed to nanomaterials, which are still challenging for reliable analysis. An air–liquid interface has been developed for the exposure of biological samples to nanomaterial-containing aerosols. The system exposes transmission electron microscopy (TEM) grids under reproducible conditions, whilst also allowing characterization of aerosol composition with mass spectrometry. Such an approach enables correlative measurements combining biological with physicochemical analysis. These case studies demonstrate that standardization and automation of sample preparation setups, combined with appropriate measurement processes and data reduction are crucial steps towards more reliable and reproducible data. KW - Sample preparation KW - Automation KW - Nanomaterial analysis KW - Standardization PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543988 DO - https://doi.org/10.3390/molecules27030985 VL - 27 IS - 3 SP - 1 EP - 22 PB - MDPI AN - OPUS4-54398 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertovic, Marija T1 - Automation in non-destructive testing: new risks and risk sources N2 - Over the past couple of decades Non-Destructive Testing (NDT) has seen a significant increase in the use of automation. In addition to increased reliability, objectivity, consistency, repeatability, productivity, and so on, automating parts of the process is expected to decrease the potential for human error. However, the literature on human-automation interaction suggests that automation is not only associated with benefits, but also with new risks and risk sources. First, this paper will present the methodology used to identify—for the first time—possible risks associated with mechanised data acquisition and corresponding data evaluation. Moreover, it will highlight possible risks, their causes, consequences, and ways of preventing them. Second, those preventive measures will be further analysed by examining new risks that can arise from their implementation, i.e. potential for failure that can arise from (a) working with automated defect-detection and sizing aids, (b) implementing human redundancy, and (c) improvement of the inspection procedures without due consideration of the procedure users. And third, some optimisations strategies will be provided. The purpose of this work is to show that mechanised testing is associated with potential for failure and that the sources of those risks go beyond single inspectors and need to be looked at in the interaction of people with other systems, i.e. the technology, the team and, most importantly, the organisation. T2 - 55th annual Conference of the British Institute for Non-Destructive Testing CY - Nottingham, United Kingdom of Great Britain and Northern Ireland DA - 12.09.2016 KW - Human Factors KW - Automation KW - NDT Reliability PY - 2016 AN - OPUS4-65458 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 - CONF A1 - Gornushkin, Igor B. T1 - Back Deposition of Titanium Oxides under Laser Ablation of Titanium: Simulation and Experiment N2 - Titanium is widely used in medicine for implants and prostheses, thanks to its high biocompatibility, good mechanical properties, and high corrosion resistance. Pure titanium, however, has low wear resistance and may release metallic titanium into surrounding tissues. Structuring and coating its surface with oxide layers are necessary for high wear resistance and improved biocompatibility. In this work, a combination of theoretical and experimental methods was used to study processes responsible for deposition of titanium oxides during ablation of titanium in air. The deposition process was modeled via the Navier-Stokes equations that accounted for the material removal and accumulation of the deposit on the ablation surface. The chemical part was based on the equilibrium model embedded into the hydrodynamic code. Simulations showed that the most active zone of production of condensed titanium oxides were at plasma periphery whereas a zone of strong condensation of titanium metal was above the molten pool. In experiment, a pulsed Yb fiber laser was scanned across a titanium surface. The temperature and composition of the plasma were inferred from plasma emission spectra. The post-ablation surface was analyzed by SEM, TEM, STEM, AFM, and XRD. The developed model well reproduced the main features of experimental data. It was concluded that the deposition of condensed metal oxides from the plasma is a principal mechanism of formation of nanoporous oxide layer on the metal surface. The method of surface structuring and modification by nanosecond laser ablation can be developed into a useful technology that may find applications in medicine, photonics, and other areas. T2 - SciX 2022, The Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) CY - Cincinnati, OH, USA DA - 02.10.2022 KW - Surface coating KW - Laser ablation KW - Plasma modeling PY - 2022 AN - OPUS4-55969 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerbeit, Marco T1 - Background oriented Schlieren measurements for pressure relief systems in the free field N2 - Shock waves or shocks are a supersonic phenomenon in which the flow variables change abruptly in a thin layer. These occur with super sonic flow, such as the supersonic flight of airplanes or rockets or with explosions. As the pressure, temperature and density change in a shock, this can be recorded. The most commonly used approach is the use of pressure sensors. Pressure information is only available at the certain locations where the sensors are installed. Any body, such as free-standing sensors, that is introduced into the flow, distorts it. Therefore, not inverse measurement methods for measuring flow variables, such as the background orientated schlieren (BOS) method or the partical image velocimetry (PIV), are used. For this reason, a BOS setup was carried out in an open field at the Test Site Technical Safety (TTS) of BAM using a shock wave generator to visualize the shocks that result from a gas explosion. These investigations are presented in this paper. The aim is also to draw conclusions about the pressure change caused by the shock and the advantages that such a simple structure provides to the tests. T2 - 30th International Colloquium on the Dynamics of Explosions and Reactive Systems CY - Ottawa, Canada DA - 28.07.2025 KW - BOS KW - Blast KW - Shock PY - 2025 AN - OPUS4-63915 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 - Mishurova, Tatiana A1 - Bruno, Giovanni T1 - BAM activities in material characterization by advanced X-ray imaging N2 - The overview of the activity of Federal Institute for Material Research and Testing (BAM, Belin, Germany) in the field of additively manufacturing material characterization will be presented. The research of our group is focused on the 3D imaging of AM materials by means of X-ray Computed Tomography at the lab and at synchrotron, and the residual stress characterization by diffraction (nondestructive technique). Also, two successful research project in collaboration with CAM2, Sweden are presented. T2 - CAM2 Annual Meeting CY - Gothenburg, Sweden DA - 25.10.2023 KW - Additive manufacturing KW - Residual stress KW - X-ray computed tomography PY - 2023 AN - OPUS4-58828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna T1 - BAM activities on microplastics N2 - The presentation is about BAM's activities on the topic of microplastics. It describes what BAM has done in this field in recent years. On the one hand, TED-GC/MS is presented as an analytical method, on the other hand, currently available microplastic reference materials are presented. T2 - JRC/BAM Workshop on ILC CY - Online meeting DA - 11.02.2021 KW - Microplastic KW - TED-GC/MS KW - Microplastic particles KW - Reference materials PY - 2021 AN - OPUS4-52120 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meyer, Klas T1 - BAM quality toolbox framework for qNMR N2 - Accreditation of analytical methods, either according to GxP or ISO regulations, requires a comprehensive quality management system. General quality documents are often already in place, which need to be extended by method-specific documentation. In this presentation we like to show an idea of a modular set of standard operating procedures (SOP) specifically developed meeting the requirements for quantitative NMR. The future goal is to collaborate with different accreditated NMR laboratories to compile a universal set of SOP and other quality documents that can be modified and used as a starting point for developing your own quality system for applications of qNMR in a regulated environment. T2 - ValidNMR Workshop at Practical Applications of NMR in Industry Conference (PANIC) CY - Online meeting DA - 22.10.2020 KW - ValidNMR KW - Validation KW - NMR spectroscopy KW - ISO 17025 KW - GxP PY - 2020 AN - OPUS4-51466 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Radnik, Jörg T1 - BAM reference data - XPS raw data of Al-coated titania nanoparticles (JRCNM62001a and JRCNM62002a) N2 - XPS raw data of Al-coated titania nanoparticles (JRCNM62001 and JRCNM62002a) provided by the JRC repository are provided. KW - XPS KW - Titania nanoparticles KW - BAM reference data PY - 2021 DO - https://doi.org/10.5281/zenodo.4986068 PB - Zenodo CY - Geneva AN - OPUS4-52880 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -