TY - JOUR A1 - Zhang, T. A1 - Sens-Schönfelder, C. A1 - Epple, Niklas A1 - Niederleithinger, Ernst T1 - Imaging of Small-Scale Heterogeneity and Absorption Using Adjoint Envelope Tomography: Results From Laboratory Experiments N2 - To complement the information provided by deterministic seismic imaging at length scales above a certain resolution limit we present the first application of adjoint envelope tomography (AET) to experimental data. AET uses the full envelopes of seismic records including scattered coda waves to obtain information about the distribution of absorption and small-scale heterogeneity which provide complementary information about the investigated medium. Being below the resolution limit this small-scale structure cannot be resolved by conventional tomography but still affects wave propagation by attenuating ballistic waves and generating scattered waves. Using ultrasound data from embedded sensors in a meter-sized concrete specimen we image the distribution of absorption and heterogeneity expressed by the intrinsic quality factor Q−1 and the fluctuation strength ɛ that characterizes the strength of the heterogeneity. The forward problem is solved by modeling the 2-D multiple nonisotropic scattering in an acoustic medium with spatially variable heterogeneity and attenuation using the Monte-Carlo method. Gradients for the model updates are obtained by convolution with the back-propagated envelope misfit using the adjoint formalism in analogy to full waveform inversion. We use a late coda time window to invert for absorption and an earlier time window to infer the distribution of heterogeneity. The results successfully locate an area of salt oncrete with increased scattering and concentric anomalies of intrinsic attenuation. The resolution test shows that the recovered anomalies constitute reasonable representations of internal structure of the specimen. KW - Ultrasound KW - Scattering KW - Tomography KW - Concrete KW - Heterogeneity PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-563163 DO - https://doi.org/10.1029/2022JB024972 SN - 2169-9313 VL - 127 IS - 11 SP - 1 EP - 21 PB - American Geophysical Union AN - OPUS4-56316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst A1 - Guangliang, Y. A1 - Mahon, D. A1 - Gardner, S. T1 - Muon tomography applied to assessment of concrete structures: First experiments and simulations. N2 - Non-destructive techniques for reinforced or prestressed concrete inspection such as ultrasound or radar have found regular, successful practical application but sometimes suffer from limited resolution and accuracy, imaging artefacts or restrictions in detecting certain features. Until the 1980s X-ray transmission was used in case of special demands and showed a much better resolution than other NDT techniques. However, due to safety concerns and cost issues, this method is almost never used anymore. Muon tomography has received much attention recently. Novel detectors for cosmic muons and tomographic imaging algorithms have opened new fields of application. As a first step towards practical application in civil engineering and as a proof of concept we used an existing system to image the interior of a reference reinforced 600 kg concrete block. Even with a yet not optimized setup for this kind of investigation, the muon imaging results are at least of similar quality compared to ultrasonic and radar imaging, potentially even better. In a second step, we have performed simulations to assess the potential for a set of important testing problems such as grouting defects in tendon ducts. The next steps include the development of mobile detectors and optimizing acquisition and imaging parameters. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Muon tomography KW - Concrete KW - Inspection KW - Simulation PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-563224 UR - https://www.ndt.net/article/ndtce2022/paper/60943_manuscript.pdf SP - 1 EP - 8 PB - NDT.net AN - OPUS4-56322 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst A1 - Guangliang, Y. A1 - Mahon, D. A1 - Gardner, S. T1 - Muon tomography applied to assessment of concrete structures: First experiments and simulations. N2 - Non-destructive techniques for reinforced or prestressed concrete inspection such as ultrasound or radar have found regular, successful practical application but sometimes suffer from limited resolution and accuracy, imaging artefacts or restrictions in detecting certain features. Until the 1980s X-ray transmission was used in case of special demands and showed a much better resolution than other NDT techniques. However, due to safety concerns and cost issues, this method is almost never used anymore. Muon tomography has received much attention recently. Novel detectors for cosmic muons and tomographic imaging algorithms have opened new fields of application. As a first step towards practical application in civil engineering and as a proof of concept we used an existing system to image the interior of a reference reinforced 600 kg concrete block. Even with a yet not optimized setup for this kind of investigation, the muon imaging results are at least of similar quality compared to ultrasonic and radar imaging, potentially even better. In a second step, we have performed simulations to assess the potential for a set of important testing problems such as grouting defects in tendon ducts. The next steps include the development of mobile detectors and optimizing acquisition and imaging parameters. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Muon tomography KW - Concrete KW - Inspection KW - Simulation PY - 2022 AN - OPUS4-56323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Kulow, A. A1 - Reinholz, Uwe A1 - de Oliveira Guilherme Buzanich, Ana A1 - Emmerling, Franziska A1 - Streli, C. A1 - Fittschen, U. E. A. A1 - Hampel, S. T1 - Energy Resolved Imaging with Coded Apertures N2 - Our aim is to develop a simple and inexpensive method for full field X-ray fluorescence imaging.We combine an energydispersive array detector with a coded aperture to obtain high resolut ion images. To obtain the information from the recorded image a reconstruction step is necessary. The reconstruction methods we have developed, were tested on simulated data and then applied to experimental data. The first tests were carried out at the BAMline @BESSY II. This method enables the simultaneous detection of multiple elements,which is important e.g. in the field of catalysis. T2 - SRI 2021 CY - Online meeting DA - 28.3.2022 KW - Synchrotron KW - BAMline KW - Machine Learning KW - Coded Aperture PY - 2022 AN - OPUS4-56298 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Ladu, Luana A1 - Koch, Claudia A1 - Asna Ashari, Parsa A1 - Blind, K. A1 - Castka, P. T1 - Digitalization in conformity assessment in West Africa - A QI-FoKuS study N2 - This report summarizes findings from the first comprehensive study on digitalization in conformity assessment in West Africa. The reults are based on data from a survey among conformity assessment bodies (CABs) conducted in 2022. It highlights the digital maturity of the organizations, the motives, benefits and obstacles of digital transformation as well as the actual technology trends. This study is part of a global project that covers various other countries (see www.qi-fokus.de). KW - COVID-19 KW - Calibration KW - Certification KW - Conformity assessment KW - Conformity assessment body KW - Digital transformation KW - Digitalization KW - Laboratory KW - Quality infrastructure KW - TIC KW - Testing PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-563631 UR - https://www.qi-fokus.de SP - 1 EP - 45 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-56363 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Ladu, Luana A1 - Koch, Claudia A1 - Asna Ashari, Parsa A1 - Blind, K. A1 - Castka, P. T1 - Digitalization in conformity assessment in Mexico - A QI-FoKuS study N2 - This report summarizes findings from the first comprehensive study on digitalization in conformity assessment in Mexico. The reults are based on data from a survey among conformity assessment bodies (CABs) conducted in 2022. It highlights the digital maturity of the organizations, the motives, benefits and obstacles of digital transformation as well as the actual technology trends. This study is part of a global project that covers various other countries (see www.qi-fokus.de). KW - COVID-19 KW - Calibration KW - Certification KW - Conformity assessment KW - Conformity assessment body KW - Digital transformation KW - Digitalization KW - Laboratory KW - Quality infrastructure KW - TIC KW - Testing PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-563645 UR - https://www.qi-fokus.de SP - 1 EP - 44 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-56364 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Koch, Claudia A1 - Ladu, Luana A1 - Asna Ashari, Parsa A1 - Blind, K. A1 - Castka, P. T1 - Digitalization in conformity assessment in New Zealand - A QI-FoKuS study N2 - This report summarizes findings from the first comprehensive study on digitalization in conformity assessment in New Zealand. The reults are based on data from a survey among conformity assessment bodies (CABs) conducted in 2022. It highlights the digital maturity of the organizations, the motives, benefits and obstacles of digital transformation as well as the actual technology trends. This study is part of a global project that covers various other countries (see www.qi-fokus.de). KW - COVID-19 KW - Calibration KW - Certification KW - Conformity Assessment KW - Conformity assessment body KW - Digital transformation KW - Digitalization KW - Laboratory KW - Quality infrastructure KW - TIC KW - Testing PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-564038 UR - https://www.qi-fokus.de SP - 1 EP - 44 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-56403 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Güttler, Arne A1 - Richter, Maria A1 - Würth, Christian A1 - Resch-Genger, Ute T1 - New Reference Materials for Quantification and Standardization of Fluorescence-based Measurements N2 - Luminescence techniques are amongst the most commonly used analytical methods in the life and material sciences due to their high sensitivity and non-destructive and multiparametric character. Photoluminescence signals are, however, affected by wavelength-, polarization-, and time-dependent instrument specific effects and the compound-specific photoluminescence quantum yield. The former hamper the comparability of fluorescence measurements, while the relative determination of the latter requires suitable quantum yield standards with well-known photoluminescence quantum yields. For the simple correction of instrument specific effects in the wavelength region of 300 nm to 950 nm, the set of the five certified spectral fluorescence standards (CRM) BAM-F001 – BAM-F005, has been extended to the NIR range by including two new fluorescence standards currently under certification. T2 - 17th conference on Methods and Applications in Fluorescence CY - Gothenburg, Sweden DA - 11.09.2022 KW - Luminescence KW - Photoluminescence KW - Fluorescence KW - Quantum yield KW - Certified reference material KW - Standard PY - 2022 AN - OPUS4-56441 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Lisec, Jan T1 - CorMID - Correct Mass Isotopologue Distribution Vectors N2 - The investigation of metabolic fluxes and metabolite distributions within cells by means of tracer molecules is a valuable tool to unravel the complexity of biological systems. Technological advances in mass spectrometry (MS) technology such as atmospheric pressure chemical ionization (APCI) coupled with high resolution (HR), not only allows for highly sensitive analyses but also broadens the usefulness of tracer-based experiments, as interesting signals can be annotated de novo when not yet present in a compound library. However, several effects in the APCI ion source, i.e., fragmentation and rearrangement, lead to superimposed mass isotopologue distributions (MID) within the mass spectra, which need to be corrected during data evaluation as they will impair enrichment calculation otherwise. Here, we present and evaluate a novel software tool to automatically perform such corrections. We discuss the different effects, explain the implemented algorithm, and show its application on several experimental datasets. This adjustable tool is available as an R package from CRAN. KW - Mass Spectrometry KW - Software KW - R package KW - Mass Isotopomer Distribution KW - Flux Analysis PY - 2022 UR - https://github.com/cran/CorMID/ PB - GitHub CY - San Francisco, CA, USA AN - OPUS4-56442 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strangfeld, Christoph A1 - Klewe, Tim T1 - Comparison of the Calcium Carbide Method and Darr Drying to Quantify the Amount of Chemically Bound Water in Early Age Concrete N2 - Hydration is the exothermic reaction between anhydrous cement and water, which forms the solid cement matrix of concrete. Being able to evaluate the hydration is of high interest for the use of both conventional and more climate-friendly building materials. The experimental monitoring is based on temperature or moisture measurements. The first needs adiabatic conditions, which can only be achieved in laboratory. The latter is often measured comparing the weight of the material sample before and after oven drying, which is time-consuming. This study investigates the moisture content of two cement-based and two calcium sulphate based mixtures for the first 90 days by using the calcium carbide method and oven drying at 40 °C and 105 °C (Darr method). Thereby, the amount of chemically bound water is determined to derive the degree of hydration. The calcium carbide measurements highly coincide with oven drying at 40 °C. The calcium carbide method is therefore evaluated as a suitable alternative to the time-consuming Darr drying. The prompt results are seen as a remarkable advantage and can be obtained easily in laboratory as well as in the field. KW - Concrete KW - Hydration KW - Material moisture KW - Calcium carbide method KW - Bound water KW - Darr method KW - Oven drying KW - Chemisorption KW - Physisorption PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-564519 DO - https://doi.org/10.3390/ma15238422 VL - 15 IS - 23 SP - 1 EP - 16 PB - MDPI AN - OPUS4-56451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Tchipilov, Teodor A1 - Meyer, Klas A1 - Weller, Michael G. T1 - Quantitative 1H nuclear magnetic resonance (qNMR) of aromatic amino acids for protein quantification N2 - qNMR is a valuable technique for metrological studies due to the uniformity of its signal response for all chemical species of an isotope of interest, which enables compound-independent calibration. However, protein quantification remained challenging as large molecules produce wide, low-intensity signals that reduce the already low sensitivity. Combining qNMR with the hydrolysis of protein samples into amino acids circumvents many of these issues and facilitates the use of NMR spectroscopy for absolute protein and peptide quantification.In this work, different conditions have been tested for quantifying aromatic amino acids and proteins. First, we examined the pH-based signal shifts in the aromatic region. The preferable pH depends on the selection of the amino acids for quantification and which internal standard substance should be used to avoid peak overlap. Several aromatic compounds, such as terephthalic acid, sulfoisophthalic acid, and benzene tricarboxylic acid, have been applied as internal standards. The quantification of amino acids from an amino acid standard, as well as from a certified reference material (bovine serum albumin), was performed. Using the first two suggested internal standards, recovery was ~ 97 % for histidine, phenylalanine, and tyrosine at a concentration of approximately 1 mM in solution. Acidic hydrolysis of a certified reference material (CRM) of bovine serum albumin (BSA) and subsequent quantification of Phe and Tyr yielded recoveries of 98 ± 2 and 88 ± 4 %, respectively, at a protein concentration of 16 g/L or 250 µM. KW - Amino acid analysis KW - AAA KW - Protein hydrolysis KW - Metrology KW - Traceability KW - Reference materials KW - Internal standards KW - Calibration PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-564520 DO - https://doi.org/10.20944/preprints202211.0569.v1 SP - 1 EP - 13 PB - MDPI CY - Basel AN - OPUS4-56452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kulow, Anicó A1 - de Oliveira Guilherme Buzanich, Ana A1 - Reinholz, Uwe A1 - Emmerling, Franziska A1 - Hampel, S. A1 - Fittschen, UEA A1 - Streli, C. A1 - Radtke, Martin T1 - Reconstruction for coded aperture full-field x-ray fluorescence imaging N2 - X-ray fluorescence imaging is a well-established tool in materials characterization. In this work, we present the adaption of coded aperture imaging to full-field X-ray fluorescence imaging at the synchrotron. Coded aperture imaging has its origins in astrophysics, and has several advantages: Coded apertures are relatively easy to fabricate, achromatic, allow a high photon throughput, and high angular acceptance. Coded aperture imaging is a two-step-process, consisting of the measurement process and a reconstruction step. Different programs have been written, for the raytracing/forward projection and the reconstruction. Experiments with coded aperture in combination with a Color X-ray Camera and an energy-dispersive area detector, have been conducted at the BAMline. Measured samples were successfully reconstructed, and gave a 9.1-fold increase in count rate compared to a polycapillary optic. KW - Synchrotron KW - BAMline KW - Coded Aperture PY - 2022 SN - 1097-0002 VL - 65 SP - 57 EP - 70 PB - Cambridge University Press CY - Cambridge AN - OPUS4-56350 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steinhäuser, Lorin A1 - Piechotta, Christian A1 - Westphalen, Tanja A1 - Kaminski, Katja T1 - Evaluation, comparison and combination of molecularly imprinted polymer solid phase extraction and classical solid phase extraction for the preconcentration of endocrine disrupting chemicals from representative whole water samples N2 - Estrogens are endocrine disrupting chemicals and of high concerns due to demonstrated harmful effects on the environment and low effect levels. For monitoring and risk assessment, several estrogens were included in the "watch list" of the EU Water Framework Directive which sets very low environmental quality standard (EQS) levels for Estrone (E1) and 17β-Estradiol (E2) of 0.4 ng L−1 and for 17α-Ethinylestradiol (EE2) of 0.035 ng L−1 requiring sensitive detection methods, as well as extensive sample preparation. A sensitive, derivatization-free, isotope dilution calibration HPLC-MS/MS method for a panel of 5 selected estrogens (including the 3 estrogens of the EU WFD watchlist), and a procedure for the reproducible preparation of a representative whole water matrix including mineral water, humic acids and solid particulate matter are presented. These are used in a diligent comparison of classical solid phase extraction (SPE) on hydrophilic-lipophilic balanced (HLB) phase to SPE on an estrogen-specific molecularly imprinted polymer phase (MISPE) for ultra-trace levels of the analytes (1–10 ng L−1). Additionally, a two-step procedure combining HLB SPE disks followed by MISPE is evaluated. The tow-step procedure provides superior enrichment, matrix removal and sample throughput while maintaining comparable recovery rates to simple cartridge SPE. Estimated method quantification limits (MQLs) range from 0.109–0.184 ng L−1 and thus meet EQS-levels for E1 and E2, but not EE2. The representative whole water matrix provides a reproducible comparison of sample preparation methods and lays the foundation for a certified reference material for estrogen analysis. The presented method will serve as the basis for an extended validation study to assess its use for estrogen monitoring in the environment. KW - Estrogens KW - Whole water samples KW - Molecular imprinted polymers KW - EU-WFD PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-563547 DO - https://doi.org/10.1016/j.talo.2022.100163 SN - 2666-8319 VL - 6 SP - 1 EP - 5 PB - Elsevier B.V. CY - Amsterdam, Niederlande AN - OPUS4-56354 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Morcillo, Dalia A1 - Abad Andrade, Carlos Enrique A1 - Winckelmann, Alexander A1 - Frick, D. A1 - Jacobsen, L. A1 - Richter, Silke A1 - Recknagel, Sebastian A1 - Vogl, Jochen A1 - Panne, Ulrich 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 - Arndt, R.W. A1 - Grosse, C.U, A1 - Maehner, D. A1 - Niederleithinger, Ernst A1 - Taffe, A. A1 - Algernon, D. A1 - Berger, J. A1 - Kessler, S. A1 - Krueger, M. A1 - Kruschwitz, Sabine A1 - Ufermann-Wallmeier, D. A1 - Walther, A. T1 - Non-destructive testing in civil engineering: A memorandum for teaching at German-speaking universities N2 - This contribution summarizes actual developments and draft fundamental teaching topics in the field of nondestructive testing in civil engineering (NDT-CE). It is based on the first memorandum on teaching and research in the field of NDT-CE at German speaking universities and provides an overview of the academic education and highlights possible focuses, especially in teaching but also takes into account noteworthy developments and topics in research in the field of NDT-CE. Suggestions are given for the development and advancement of the teaching curricula in regards to a comprehensive and sound professional education of students in civil engineering and adjacent disciplines. T2 - NDT-CE 2022 CY - Zurich, Switzerland DA - 16.08.2022 KW - Curriculum KW - NDT-CE KW - University KW - Competencies PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-563269 UR - https://www.ndt.net/article/ndtce2022/paper/61547_manuscript.pdf SP - 1 EP - 10 PB - NDT.net AN - OPUS4-56326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Oster, Simon A1 - Becker, Tina A1 - Breese, Philipp Peter A1 - Scheuschner, Nils A1 - Maierhofer, Christiane A1 - Ulbricht, Alexander A1 - Frisch, Tobias A1 - Mohr, Gunther A1 - Altenburg, Simon T1 - Defect prediction in laser powder bed fusion based on thermographic features utilizing convolutional neural networks N2 - The appearance of irregularities such as keyhole porosity is a major challenge for the production of metal parts by laser powder bed fusion (PBF-LB/M). The utilization of thermographic in-situ monitoring is a promising approach to extract the thermal history which is closely related to the formation of irregularities. In this study, we investigate the utilization of convolutional neural networks to predict keyhole porosity based on thermographic features. Here, the porosity information calculated from an x-ray micro computed tomography scan is used as reference. Feature engineering is performed to enable the model to learn the complex physical characteristics of the porosity formation. The model is examined with regard to the choice of hyperparameters, the significance of thermal features and characteristics of the data acquisition. Based on the results, future demands on irregularity prediction in PBF-LB/M are derived. T2 - GIMC SIMAI YOUNG 2022 CY - Pavia, Italy DA - 29.09.2022 KW - Laser Powder Bed Fusion KW - Thermography KW - In-situ Monitoring KW - Convolutional Neural Networks PY - 2022 AN - OPUS4-56331 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Oster, Simon A1 - Becker, Tina A1 - Breese, Philipp Peter A1 - Scheuschner, Nils A1 - Altenburg, Simon T1 - Machine Learning based defect detection in Laser Powder Bed Fusion utilizing thermographic feature data N2 - The formation of irregularities such as keyhole porosity pose a major challenge to the manufacturing of metal parts by laser powder bed fusion (PBF-LB/M). In-situ thermography as a process monitoring technique shows promising potential in this manner since it is able to extract the thermal history of the part which is closely related to the formation of irregularities. In this study, we investigate the utilization of machine learning algorithms to detect keyhole porosity on the base of thermographic features. Here, as a referential technique, x-ray micro computed tomography is utilized to determine the part's porosity. An enhanced preprocessing workflow inspired by the physics of the keyhole irregularity formation is presented in combination with a customized model architecture. Furthermore, experiments were performed to clarify the role of important parameters of the preprocessing workflow for the task of defect detection . Based on the results, future demands on irregularity prediction in PBF-LB/M are derived. T2 - International Conference on NDE 4.0 CY - Berlin, Germany DA - 24.10.2022 KW - Laser Powder Bed Fusion KW - Thermography KW - In-situ Monitoring KW - Convolutional Neural Networks PY - 2022 AN - OPUS4-56332 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koch, Claudia A1 - Ladu, Luana A1 - Asna Ashari, Parsa T1 - Global status and trends of Digital Transformation in conformity assessment - Insights from our QI-FoKuS study N2 - This presentation summarizes major findings from an international study in 16 countries and regions on digital transformation in conformity assessment bodies such as testing and calibration laboratories or certification and inspection bodies. It draws from survey data of 1.476 participants and specifically highlights findings on the digital maturity of the organizations, providing an international comparison. T2 - 5º Simposio Latinoamericano de Laboratorios de Calibración y Ensayos - ASOCEC 2022 CY - Online meeting DA - 22.11.2022 KW - Quality Infrastructure KW - Digitalization KW - Testing laboratories KW - Conformity assessment KW - Certification KW - Digital transformation KW - TIC PY - 2022 AN - OPUS4-56385 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Simon, Fabian A1 - Gehrenkemper, Lennart A1 - Meermann, Björn T1 - HR-CS-GFMAS as a new screening method for emerging pollutants – per- and polyfluoroalkyl substances (PFASs) in the environment N2 - Per- and polyfluorinated alkyl substances (PFASs) are a group of several thousand individual compounds. Many 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. In the present work a HR-CS-GFMAS method for EOF analysis was utilized for suspended particulate matter (SPM) analysis in German rivers in time lines from 2005–2020. Therefore, time and spatial resolved trends were investigated. In addition, SPM samples were analyzed for the Σ41PFAS using target analysis based on UHPLC-HRMS. Overall, target analysis drastically underestimated the total PFAS burden in SPM of German rivers compared to the EOF HR-CS-GFMAS analysis. Using a fluorine mass balance approach, only 0.2% to 38.6% of the EOF was explainable using the Σ41PFAS determined with target analysis. Our study highlights the need to integrate PFAS sum parameters (e.g., EOF with HR-CS-GFMAS) in PFAS risk assessment strategies. T2 - Adlershofer Forschungsforum 2022 CY - Berlin, Germany DA - 11.11.2022 KW - PFAS KW - HR-CS-GFMAS KW - Fluorine KW - SPM PY - 2022 AN - OPUS4-56392 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krankenhagen, Rainer T1 - Comment on "Sizing the depth and width of ideal delaminations using modulated photothermal radiometry" [J. Appl. Phys. 131, 085106 (2022)] N2 - Comment on the article "Sizing the depth and width of ideal delaminations using modulated photothermal radiometry" by Agustín Salazar and Arantza Mendioroz, Journal of Applied Physics 131, 085106 (2022, https://doi.org/10.1063/5.0085178). KW - Ideal delamination KW - Modulated photothermal radiometry KW - Delamination depth KW - Delamination width PY - 2022 DO - https://doi.org/10.1063/5.0107603 VL - 132 SP - 1 PB - AIP CY - Melville, NY AN - OPUS4-56261 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -