TY - JOUR A1 - Kader, A. A1 - Brangsch, J. A1 - Kaufmann, Jan Ole A1 - Zhao, J. A1 - Mangarova, D. B. A1 - Moeckel, J. A1 - Adams, L. C. A1 - Sack, I. A1 - Taupitz, M. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Molecular MR Imaging of Prostate Cancer N2 - This review summarizes recent developments regarding molecular imaging markers for magnetic resonance imaging (MRI) of prostate cancer (PCa). Currently, the clinical standard includes MR imaging using unspecific gadolinium-based contrast agents. Specific molecular probes for the diagnosis of PCa could improve the molecular characterization of the tumor in a non-invasive examination. Furthermore, molecular probes could enable targeted therapies to suppress tumor growth or reduce the tumor size. KW - Prostate cancer KW - Magnetic resonance imaging KW - Molecular imaging KW - Imaging KW - Molecular marker KW - Screening KW - MRI KW - Diagnosis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519503 DO - https://doi.org/10.3390/biomedicines9010001 VL - 9 IS - 1 SP - 1 EP - 17 PB - MDPI CY - Basel AN - OPUS4-51950 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertovic, Marija T1 - Psychology at BAM: Is it science and how can we benefit from it? N2 - The aim of this presentation is twofold: first, to present the field of psychology including its research methods and, second, to show on an example how psychology can be used in material research. The example is of the study of human factors in non-destructive testing (NDT), in which the author has more than 10 years of experience. The conclusion is that psychological methods can be used to identify human-related problems during different tasks and to generate mitigation strategies that can be used to decrease human error and enhance safety. T2 - Abteilungsseminar der Abteilung 8 CY - Berlin, Germany DA - 20.04.2020 KW - Psychology KW - Human factors KW - Non-destructive testing (NDT) KW - Safety PY - 2020 AN - OPUS4-51920 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertovic, Marija T1 - Human machine interaction in the era of industry 4.0 N2 - The fourth industrial revolution (also known as “Industry 4.0”) promises to relieve people from manual and physical work by developing cyber-physical systems and smart automation and thereby achieving a more efficient, reliable and safe performance. This will change people’s work from being operators of the system into becoming strategical decision makers and flexible problem solvers. This shift will require a new division of work between people and technical systems, a new division of responsibilities and new ways of interacting with technology, which in turn will pose new demands on people. People will require different physical and cognitive capabilities, different competencies and new strategies to cope with the upcoming challenges. The focus of Industry 4.0 is therefore on designing systems with human in the centre: systems that will extend people’s capabilities, that will allow collaborative work and take advantage of performances in which either people or technology excel. This presentation will focus on the benefits of consideration of human-machine interaction in the context of industry 4.0. T2 - Les assises de L’Industrie 4.0 CY - INSA Centre Val de Loire, Campus de Blois, France DA - 29.09.2020 KW - Human machine interaction KW - Industry 4.0 KW - NDT 4.0 KW - Safety KW - non-destructive testing (NDT) PY - 2020 AN - OPUS4-51921 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Molloy, J. L. A1 - Winchester, M. R. A1 - Butler, T. A. A1 - Possolo, A. M. A1 - Rienitz, O. A1 - Roethke, A. A1 - Goerlitz, V. A1 - Caciano de Sena, R. A1 - Dominguez Almeida, M. A1 - Yang, L. A1 - Methven, B. A1 - Nadeau, K. A1 - Romero Arancibia, P. A1 - Bing, W. A1 - Tao, Z. A1 - Snell, J. A1 - Vogl, Jochen A1 - Koenig, Maren A1 - Kotnala, R. K. A1 - Swarupa Tripathy, S. A1 - Elishian, C. A1 - Ketrin, R. A1 - Suzuki, T. A1 - Oduor Okumu, T. A1 - Yim, Y.-H. A1 - Heo, S. W. A1 - Min, H. S. A1 - Sub Han, M. A1 - Lim, Y. A1 - Velina Lara Manzano, J. A1 - Segoviano Regalado, F. A1 - Arvizu Torres, M. A1 - Valle Moya, E. A1 - Buzoianu, M. A1 - Sobina, A. A1 - Zyskin, V. A1 - Sobina, E. A1 - Migal, P. A1 - Linsky, M. A1 - Can, S. Z. A1 - Ari, B. A1 - Goenaga Infante, H. T1 - CCQM-K143 Comparison of Copper Calibration Solutions Prepared by NMIs/DIs N2 - CCQM-K143 is a key comparison that assesses participants’ ability to prepare single element calibration solutions. Preparing calibration solutions properly is the cornerstone of establishing a traceability link to the International System of Units (SI), and therefore should be tested in order to confirm the validity of CCQM comparisons of more complex materials. CCQM-K143 consisted of participants each preparing a single copper calibration solution at 10 g/kg copper mass fraction and shipping 10 bottled aliquots of that solution to the coordinating laboratory, the National Institute of Standards and Technology (NIST). The masses and mass fraction for the prepared solutions were documented with the submitted samples. The solutions prepared by all participants were measured at NIST by high performance inductively coupled plasma optical emission spectroscopy (HP-ICP-OES). The intensity measurements for copper were not mapped onto values of mass fraction via calibration. Instead, ratios were computed between the measurements for copper and simultaneous measurements for manganese, the internal standard, and all subsequent data reductions, including the computation of the KCRV and the degrees of equivalence, were based on these ratios. Other than for two participants whose measurement results appeared to suffer from calculation or preparation errors, all unilateral degrees of equivalence showed that the measured values did not differ significantly from the KCRV. These results were confirmed by a second set of ICP-OES measurements performed by the Physikalisch-Technische Bundesanstalt (PTB). CCQM-K143 showed that participants are capable of preparing calibration solutions starting from high purity, assayed copper metal. Similar steps are involved when preparing solutions for other elements, so it seems safe to infer that similar capabilities should prevail when preparing many different, single-element solutions. KW - Metrology KW - Primary calibration solution KW - Traceability PY - 2020 DO - https://doi.org/10.1088/0026-1394/58/1A/08006 SN - 0026-1394 VL - 58 IS - 1A SP - 08006 PB - IOP Science CY - Cambridge AN - OPUS4-51983 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bulling, Jannis A1 - Franosch, Georg A1 - Lugovtsova, Yevgeniya A1 - Prager, Jens ED - Rizzo, P. ED - Milazzo, A. T1 - Sensitivity of Ultrasonic Guided Waves to Elastic Constants: A Numerical Study N2 - The dispersive properties of Lamb waves can be utilised for material characterisation because the frequency-wavenumber-relationship, as well as the group velocity, depend on material parameters. These dependencies make a non-destructive estimation of an elastic constant possible. This preliminary study investigates the sensitivity of dispersion curves caused by a change in elastic constants. The Scaled Boundary Finite Element Method is used to compute special dispersion curves, which show the sensitivity value of the frequency and group velocity as a colour value. This representation allows for easy identification of patterns and local effects. Two sets of dispersion curves are presented, one set for a steel plate and the other set for a plate made of a carbon fibre reinforced polymer. In general, we notice that the sensitivity often increases with the frequency and that higher-order modes seem to be more suitable for material characterisation. Moreover, specific modes respond to material changes while others are relatively unaffected, which must be taken into consideration for material characterisation. T2 - European Workshop on Structural Health Monitoring (EWSHM 2020) CY - Online meeting DA - 06.07.2020 KW - Scaled Boundary Finite Element Method KW - Lamb waves KW - Dispersion curves KW - Carbon fibre reinforced polymer KW - Transverse isotropy PY - 2021 SN - 978-3-030-64593-9 DO - https://doi.org/10.1007/978-3-030-64594-6_73 VL - 127 SP - 759 EP - 768 PB - Springer CY - Cham AN - OPUS4-51986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gornushkin, Igor B. T1 - Molecule formation in reactive LIBS plasmas: model and experiment N2 - Formation and detection of molecules in laser induced plasmas (LIP) is a hot topic. In analytical plasmas like LIBS, the detection of molecules is important for identification of geological and other materials, analysis of isotopes and difficult elements (Cl, F, etc.) via molecular emission. In chemical plasmas, like PECVD (plasma enhanced chemical vapor deposition) or PLD (pulsed laser deposition), molecules formed in the plasma determine a composition and a thickness of deposits. Similarly, molecules play an important role in microstructuring and oxidizing metal surfaces by laser ablation. It is unfortunate that different communities, which utilize plasma methods and seek for solutions of similar problems, do not strongly overlap, and do not fully use knowledge accumulated by each other. In this presentation, mechanisms of formation of molecules will be analyzed on the example of LIPs used for chemical vapor deposition and metal microstructuring. Theoretical analysis includes equilibrium chemistry calculations combined with plasma hydrodynamics. First, LIP excited in a gas mixture of BCl3 or BF3 with H2 or CH4 will be analyzed; this chemical system is used for obtaining deposits of refractory solid boron and boron carbide. Second, a breakdown in the SiF4 + SiCl4 gas mixtures will be described; this method allows synthesis of fluorochlorosilanes SiFxCl4-x (x = 1, 2, 3), the good etching agents (Figure). Third, solid ablation of Mo in BF3+H2 and Ti in air will be considered aimed at obtaining deposits of high hardness MoxBy and films of TixOy on textured Ti surfaces, correspondingly. In experiment, reaction gases before and after laser illumination, and solid deposits are analyzed by optical emission spectroscopy (OES), IR and mass spectrometry (MS), SEM, X-ray, and AFM. It will be shown that the hydrodynamic-chemical model adequately predicts the composition of LIPs, zones of molecular formation, dependence on reactant stoichiometry, plasma temperature and pressure. T2 - Euro-Mediterranean Symposium on Laser-Induced Breakdown Spectroscopy CY - Gijon, Spain DA - 29.11.2021 KW - Laser induced plasma KW - Plasma chemistry KW - Molecules formation KW - Plasma enhanced chemical deposition PY - 2021 AN - OPUS4-53850 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe T1 - Uncertainty budgets in surface technology: stepheigt, layerthickness, indentation hardness, adehesive strength N2 - The object (sample) and the measurement/testing procedure may always have unknown degrees of freedom, i.e. instead of 𝐯 ≥ n – 1 in many cases 𝐯 ≫ n - 1 may apply, in particular in the micro- and nano-world! T2 - 10. VDI-Fachtagung, Messunsicherheit und Prüfprozesse CY - Erfurt, Germany DA - 10.11.2021 KW - Methodology in metrology KW - Methodology in testing KW - Spectroscopic Ellipsometry KW - Instrumented Indentation Testing (IIT) KW - Centrifugal Adhesion Testing (CAT) PY - 2021 AN - OPUS4-53986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pech May, Nelson Wilbur A1 - Ziegler, Mathias T1 - Surface breaking crack detection algorithm for flying spot and line thermography based on the Canny approach N2 - In this work we introduce an algorithm based on the well-known Canny approach for effectual crack detection in thermographic films obtained using flying spot thermography (FST) or flying line thermography (FLT). The proposed algorithm performs faster than another algorithm, for crack detection, based on the application of two Sobel filters (one in x and another one in y directions). For FLT it is shown that processing 10-25 % of the thermograms of a thermographic film required to scan a whole sample is enough to obtain good results. In contrast, using the Sobel filter approach requires the processing of twice the thermographic film length. Experimental measurements are performed on a metallic component of complex shape which contains real defects, that is, surface breaking cracks due to industrial use. The specimen is tested using flying line thermography. Three different scanning speeds are tested: 10, 30 and 60 mms-1 with laser powers of 50, 60 and 120 W respectively. The sample and an infrared camera are aligned and fixed on a motorized linear stage. The diode laser LDM500 (500 W max power) is fixed on an optical bench separately from the linear stage. The results obtained with the proposed algorithm are additionally compared with a previously established algorithm for flying spot thermography based on the Sobel filter. It is shown that the proposed algorithm based on the Canny approach, can be used in automated systems for thermographic non-destructive testing. T2 - SPIE Future Sensing Technologies 2021 CY - Online meeting DA - 14.11.2021 KW - Flying line thermography KW - Flying spot thermography KW - Canny approach KW - automated thermographic nondestructive testing PY - 2021 DO - https://doi.org/10.1117/12.2603913 SP - 119140M-1 EP - 119140M-6 AN - OPUS4-53961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pech May, Nelson Wilbur A1 - Ziegler, Mathias T1 - Detection of surface breaking cracks using flying line laser thermography: A Canny-based algorithm N2 - In this work, we introduce a new algorithm for effectual crack detection using flying line laser thermography, based on the well-known Canny approach. The algorithm transforms the input thermographic sequence into an edge map. Experimental measurements are performed on a metallic component that contains surface breaking cracks due to industrial use. The specimen is tested using flying line thermography at different scanning speeds and laser input powers. Results obtained with the proposed algorithm are additionally compared with a previously established algorithm for flying spot thermography. The proposed Canny-based algorithm can be used in automated systems for thermographic non-destructive testing. T2 - Advanced Infrared Technology and Applications 2021 CY - Online meeting DA - 26.10.2021 KW - Canny approach KW - Flying line thermography KW - Crack detection PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539628 DO - https://doi.org/10.3390/engproc2021008022 SN - 2673-4591 VL - 8 IS - 1 SP - 1 EP - 4 PB - MDPI CY - Basel AN - OPUS4-53962 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönhals, Andreas T1 - Thermal behavior of high preformance polymers - Fast Scanning Calorimetry and more N2 - The glass tranistion behavior of polymers of intrinsic microporosity and polynornornes is discussed. T2 - Flash DSC Conference 2021 CY - Online meeting DA - 06.12.2021 KW - Polymer of Intrisic Maicroporosity KW - Highly permeable polynorbornenes PY - 2021 AN - OPUS4-53938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lay, Vera A1 - Buske, S. A1 - Townend, J. A1 - Kellett, R. A1 - Savage, M. A1 - Schmitt, D. R. A1 - Constantinou, A. A1 - Eccles, J. D. A1 - Gorman, A. A1 - Bertram, M. A1 - Hall, K. A1 - Lawton, D. A1 - Kofman, R. T1 - 3D Active Source Seismic Imaging of the Alpine Fault Zone and the Whataroa Glacial Valley in New Zealand N2 - The Alpine Fault zone in New Zealand marks a major transpressional plate boundary that is late in its typical earthquake cycle. Understanding the subsurface structures is crucial to understand the tectonic processes taking place. A unique seismic survey including 2D lines, a 3D array, and borehole recordings, has been performed in the Whataroa Valley and provides new insights into the Alpine Fault zone down to ∼2 km depth at the location of the Deep Fault Drilling Project (DFDP)-2 drill site. Seismic images are obtained by focusing prestack depth migration approaches. Despite the challenging conditions for seismic imaging within a sediment filled glacial valley and steeply dipping valley flanks, several structures related to the valley itself as well as the tectonic fault system are imaged. A set of several reflectors dipping 40°–56° to the southeast are identified in a ∼600 m wide zone that is interpreted to be the minimum extent of the damage zone. Different approaches image one distinct reflector dipping at ∼40°, which is interpreted to be the main Alpine Fault reflector located only ∼100 m beneath the maximum drilled depth of the DFDP-2B borehole. At shallower depths (z < 0.5 km), additional reflectors are identified as fault segments with generally steeper dips up to 56°. Additionally, a glacially over-deepened trough with nearly horizontally layered sediments and a major fault (z < 0.5 km) are identified 0.5–1 km south of the DFDP-2B borehole. Thus, a complex structural environment is seismically imaged and shows the complexity of the Alpine Fault at Whataroa. KW - Imaging KW - Signal processing KW - Seismic KW - Borehole KW - DAS PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539163 DO - https://doi.org/10.1029/2021JB023013 VL - 126 IS - 12 SP - 1 EP - 21 PB - American Geophysical Union AN - OPUS4-53916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska T1 - Shaken not stirred: enhancing the flavor of mechanochemistry N2 - Mechanochemistry is increasingly used for synthesizing soft matter materials including metal organic compounds and cocrystals.1 The ever-increasing interest in this method is contrasted by a limited mechanistic understanding of the mechanochemical reactivity and selectivity. Time-resolved in situ investigations of milling reactions provide direct insights in the underlying mechanisms.2-4 We recently introduced different setups enabling in situ investigation of mechanochemical reactions using synchrotron XRD combined with Raman spectroscopy and thermography. The presented setup allows the detection of crystalline, amorphous, eutectic, and liquid intermediates. Furthermore, the chemical composition of the reaction mixture was found to be directly correlated with changes in the temperature profile of the reaction. The resulting deeper kinetic and thermodynamic understanding of milling processes is the key for future optimization of mechanochemical syntheses. In this contribution, we will discuss our recent results investigating the formation of (polymorphic) cocrystals and coordination polymers.2,3,5 Our results indicate that in situ investigation of milling reactions offer a new approach to tune and optimize mechanochemical syntheses. T2 - BCA/BACG joint spring meeting CY - Online meeting DA - 29.03.2021 KW - Mechanochemistry KW - Cocrystals KW - Crystal Engineering PY - 2021 AN - OPUS4-53995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska T1 - Shaken not stirred: in situ investigations of mechanochemical processes N2 - Mechanochemistry has emerged as one of the most interesting synthetic protocols to produce new materials. The development of mechanochemistry as a synthetic method is supported by excellent research by many groups worldwide in a wide range of applications. The potential of mechanochemistry is also reflected in the inclusion in IUPAC’s 10 chemical innovations that will change our world’.[1] Solvent-free methodologies lead to unique chemical processes during synthesis with the consequent formation of martials with new properties.2 In this contribution, we will discuss our recent results investigating the formation of (polymorphic) cocrystals, coordination polymers, metal oxides and metal nanoparticles.[3-8] We introduced different setups enabling in situ investigation of mechanochemical reactions using synchrotron XRD combined with Raman spectroscopy and thermography. T2 - Deutsche Kristallzüchtertagung CY - Berlin, Germany DA - 06.10.2021 KW - Mechanochemistry KW - In situ real-time monitoring KW - Crystal PY - 2021 AN - OPUS4-53996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gernhard, M. A1 - Rautenberg, Max A1 - Hörner, G. A1 - Weber, B. A1 - Emmerling, Franziska A1 - Roth, C. T1 - Mechanochemical Synthesis as a Greener Way to ProduceIron-based Oxygen Reduction Catalysts N2 - Iron-based catalysts have been reported manifold and studied as platinum group metal (PGM) free alternatives for the catalysis of the oxygen reduction reaction (ORR). However, their sustainable preparation by greener synthesis approaches is usually not discussed. In this work, we propose a new method for the sustainable preparation of such catalysts by using a mechanochemical approach, with no solvents and non-toxic chemicals. The materials obtained from low temperature carbonization (700 °C) exhibit considerable and stable catalytic performance for ORR in alkaline medium. A catalyst obtained from iron hydroxide, tryptophan, dicyandiamide, and ammonium nitrate shows the best electrocatalytic Performance with an overpotential of 921 mV vs. RHE at 0.1 mA/cm2 and an electron transfer number of 3.4. KW - PGM-free catalyst KW - Oxygen Reduction Reaction KW - AEMFC KW - Mössbauer Spectroscopy KW - Sustainable Synthesis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-535326 DO - https://doi.org/10.1002/zaac.202100194 VL - 647 IS - 22 SP - 2080 EP - 2087 PB - Weinheim-VCH GmbH AN - OPUS4-53532 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rautenberg, Max T1 - The Effect of Fluorine on Catalysts for the Oxygen Reduction Reaction obtained from Metal Organic Frameworks N2 - The oxygen reduction reaction (ORR) – an important reaction in electrochemical devices, such as fuel cells - is characterized by its sluggish kinetics and therefore requires catalysis. The industry currently relies on platinum as a catalyst, although it is scarce and expensive, hindering the commercial breakthrough of fuel cells in automotive applications. Platinum-free catalysts on basis of nitrogen- and metal doped carbons (NMCs) and fluorinated carbons are promising materials to replace platinum-based catalysts for the ORR. In this work we prepared six metal-organic frameworks (MOFs) by mechanical ball mill grinding and studied their formation by in-situ powder X-ray diffraction. Furthermore, the samples were carbonized under controlled conditions (900°C, 1h, N2-atmosphere) to yield carbon materials, that were employed in ORR-electrocatalysis. The effect of Co-doping and fluorination was systematically studied and outstanding ORR activity was found for the catalyst prepared from the Co-doped fluorinated ZIF-8. T2 - International Symposium on Fluorine-specific interactions CY - Berlin, Germany DA - 27.09.2021 KW - PGM-free catalyst KW - Oxygen Reduction Reaction KW - Mechanochemistry KW - MOFs PY - 2021 AN - OPUS4-53533 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zeipert, H. A1 - Johannesmann, S. A1 - Nicolai, Marcel A1 - Lugovtsova, Yevgeniya A1 - Prager, Jens A1 - Henning, B. T1 - Quantifying the coupling strength of adhesively bonded materials by investigating mode repulsion regions N2 - In the field of non-destructive testing, Lamb waves are often used for material characterisation. The increasing computational capabilities further enable complex and detailed simulations to predict the material behaviour in reality. Since adhesive bonding of different materials is a widely used method in modern applications, a reliable measurement system to determine the quality of these adhesive bonds is needed. Investigations of the dispersive behaviour of acoustic waves in adhesively bonded multi-layered waveguides show mode repulsions in the dispersion diagrams in regions where the modes of the single materials would otherwise intersect. In previous works, changes of the distance between those modes with respect to the bonding quality are observed. The experimental data for this investigation is generated using pulsed laser radiation to excite broadband acoustic waves in plate like specimens which are detected by a piezoelectric ultrasonic transducer. Numerical data is generated using simulations via a semi-analytical finite element method. Using a combination of experimental and numerical data, the present work introduces an approach to determine a parameter which indicates the bonding quality in relation to an ideal material coupling. T2 - DAGA 2021 CY - Vienna, Austria DA - 15.08.2021 KW - Ultrasonic guided waves KW - Multi-layered structures KW - Laser excited ultrasonic waves PY - 2021 SP - 1532 EP - 1535 AN - OPUS4-53581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rautenberg, Max T1 - Fluorination and co-doping of ZIF-8 by ball mill grinding for efficient oxygen reduction electrocatalysis N2 - The oxygen reduction reaction (ORR) is a common process in a variety of electrochemical devices, like fuel cells and metal air batteries. The sluggish kinetics of the ORR require an electrocatalyst to pass this bottleneck.[1] Currently, the most used catalytical systems are platinum-based, with several drawbacks, such as the high cost, low availability, and deactivation by CO poisoning.[2] Efforts are made to develop efficient, durable and low cost catalysts to promote the commercialization of fuel cells. Non-precious metal catalysts are promising candidates for efficient ORR catalysis. It has been shown that pyrolyzing metal organic frameworks (MOFs) under inert conditions yields carbon-rich materials, with evenly distributed metal sites, which possess promising electrocatalytic activity.[3] One widely used type of MOF as ORR catalyst precursors is the zeolitic imidazole framework (ZIF) where metal cations are linked through imidazole-based ligands. Their porous nature is partially retained after carbonization, making MOFs very suitable precursor materials. Herein we report the mechanochemical synthesis and structural analysis of Co-doped ZIF-8 (Zn), as well as two polymorphs (dense and prorous) of fluorinated Co-doped CF3-ZIF-8 (Zn). The samples showed electrochemical performance comparable to platinum after carbonization for 1 h at temperatures ranging between 850 – 1000°C. T2 - XXV General Assembly and Congress of the International Union of Crystallography - IUCr 2021 CY - Prague, Czech Republic DA - 14.08.2021 KW - PGM-free catalyst KW - Oxygen Reduction Reaction KW - Mechanochemistry KW - MOFs PY - 2021 AN - OPUS4-53535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rautenberg, Max T1 - Coordination Polymers for the Applications in Electrochemical Devices N2 - Coordination polymers can be used as sacrificial templates to prepare nitrogen- and metal doped carbons (NMCs), which are promising catalysts for the oxygen reduction reaction. We at BAM employ mechanochemistry as a "green" synthetic approach to coordiantion polymers, which are throroughly characterized by methods such as XRD, XPS and sorption studies. Our collaborators can prepare NMCs from our coordination polymers and assess the catalytic activity thereof. T2 - 3rd Training School: "Mechanochemistry: from supramolecular to covalent bonds - synthesis and strctural characterization CY - Lisbon, Portugal DA - 22.03.2021 KW - PGM-free catalyst KW - Mechanochemistry KW - MOFs KW - Electrocatalysis KW - Oxygen reduction reaction (ORR) PY - 2021 AN - OPUS4-53536 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rautenberg, Max T1 - Fluorine Modified ZIF 8 for Electrochemical Catalysis: Where does the Fluorine go? N2 - Carbonization of fluorinated metal-organic frameworks (MOFs) should yield fluorinated nitrogen- and metal-doped carbons (F-NMCs), which are a combination of NMCs and fluorinated carbons, each promising electrocatalysts on their own. We synthesized two polymorphs of a fluorinated MOF by mechanical ball mill grinding, and carbonized them to yield potential electrocatalyt materials. The catalytical activity towards the oxygen reduction reaction (ORR) was examined, finding good activites. Simulations from a theoretic model helped assesing the stability of proposed catalytic sites and understanding the measured activites towards the ORR catalysis. T2 - Online symposium of the CRC 1349 "fluorine-specific interactions" CY - Online meeting DA - 29.06.2021 KW - PGM-free catalyst KW - Oxygen Reduction Reaction KW - Mechanochemistry KW - MOFs KW - Computational chemistry PY - 2021 AN - OPUS4-53538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rautenberg, Max T1 - Synthesis and characterization of fluorinated Co-Zn-Zeolitic imidazole frameworks for catalysis of the oxygen reduction reaction N2 - The oxygen reduction reaction (ORR) is a common process in a variety of electrochemical devices, like fuel cells and metal air batteries. The sluggish kinetics of the ORR require an electrocatalyst to pass this bottleneck.[1] Currently, the most used catalytical systems are platinum-based, with several drawbacks, such as the high cost, low availability, and deactivation by CO poisoning.[2] Efforts are made to develop efficient, durable and low cost catalysts to promote the commercialization of fuel cells. Non-precious metal catalysts are promising candidates for efficient ORR catalysis. It has been shown that pyrolyzing metal organic frameworks (MOFs) under inert conditions yields carbon-rich materials, with evenly distributed metal sites, which possess promising electrocatalytic activity.[3] One widely used type of MOF as ORR catalyst precursors is the zeolitic imidazole framework (ZIF) where metal cations are linked through imidazolebased ligands. Herein we report the mechanochemical synthesis, structural analysis and of Co-doped ZIF-8 (Zn), as well as its fluorinated counterpart Co-doped CF3 -ZIF-8 (Zn). The samples showed electrochemical performance comparable to platinum after carbonization for 1h at temperatures ranging between 850 – 1000°C. T2 - 15th International conference on materials chemistry (MC15) CY - Online meeting DA - 12.07.2021 KW - PGM-free catalyst KW - Oxygen Reduction Reaction KW - Mechanochemistry KW - MOFs PY - 2021 AN - OPUS4-53539 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martins, I. A1 - Carta, M. A1 - Haferkamp, Sebastian A1 - Feiler, Torvid A1 - Delogu, F. A1 - Colacino, E. A1 - Emmerling, Franziska T1 - Mechanochemical N‑Chlorination Reaction of Hydantoin: In Situ Real-Time Kinetic Study by Powder X‑ray Diffraction and Raman Spectroscopy N2 - Mechanochemistry has become a valuable tool for the synthesis of new molecules, especially in the field of organic chemistry. In the present work, we investigate the kinetic profile of the chlorination reaction of N-3-ethyl-5,5-dimethylhydantoin (EDMH) activated and driven by ball milling. The reaction has been carried out using 2 mm, 4 mm, 5 mm, 6 mm, and 8 mm ball sizes in a new small custom-made Perspex milling jar. The Crystal structure of the starting material EDMH and the 1-chloro-3-ethyl5,5′-dimethyl hydantoin (CEDMH) chlorination product was solved by single-crystal X-ray diffraction. The reaction was monitored, in situ and in real time, by both powder X-ray diffraction (PXRD) and Raman spectroscopy. Our kinetic data show that the reaction progress to equilibrium is similar at all milling ball sizes. The induction period is very short (between 10 and 40 s) when using 4 mm, 5 mm, 6 mm, and 8 mm balls. For the reaction performed with a 2 mm ball, a significantly longer induction period of 9 min was observed. This could indicate that an initial energy accumulation and higher mixing efficiency are necessary before the reaction starts. Using different kinetic models, we found that the amount of powder affected by critical loading conditions during individual impacts is significantly dependent on the ball size used. An almost linear correlation between the rate of the chemical transformations and the ball volume is observed. KW - Mechanochemistry KW - In situ real-time monitoring KW - N-Chlorination KW - Kinetics KW - Hydantoin KW - Powder X-ray diffraction KW - Raman spectroscopy PY - 2021 DO - https://doi.org/10.1021/acssuschemeng.1c03812 VL - 9 IS - 37 SP - 12591 EP - 12601 AN - OPUS4-53541 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertovic, Marija T1 - The Past and the Future of Human Factors: The “Uncontrollable” Aspect of NDT Reliability? N2 - That human factors (HF) affect the reliability of NDT is not novelty. Still, when it comes to reliability assessments, the role of people is often neglected. Reliability is typically expressed in terms of POD curves, and the effects of human and organisational factors on the inspection are typically tackled by the regulations, procedures and by the qualification and training of the inspection personnel. However, studies have shown that even the most experienced personnel can make mistakes and that the reliability in the field is never as high as the reliability measured in the POD experiments. Generally, HF are considered too unpredictable and too uncontrollable to model. If that is the fact, then what can we do? The engineering perspective to this problem has often been to find ways to automate inspections and, recently, to make use of artificial intelligence tools to decrease the direct effect of people on the inspection results and improve the overall efficiency and reliability. However, despite automation and AI, people remain the key players, though their tasks change. The contemporary approach to HF is not to engineer them out of the system but to design human-machine systems that make the best use of both. In this talk, ways of tackling HF in the design of systems and processes will be presented. T2 - Reliability of NDT webinar, The Scottish Branch of the British Institute of NDT CY - Online meeting DA - 29.01.2021 KW - Non-Destructive Testing KW - NDT KW - Human Factors KW - Reliability PY - 2021 UR - www.bindt.org/admin/Downloads/2021-01%20BINDT_Bertovic_Human%20factors_new.pdf AN - OPUS4-53544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gornushkin, Igor B. T1 - Laser induced gas breakdown in reactive mixtures N2 - Plasma-chemical approach is used for synthesis of various gaseous, liquid, and solid substances since 1960th. Nowadays, the method of plasma enhanced chemical vapor deposition (PECVD) is used for production of thin films, protective coatings, carbon-based nanostructures, high purity isotopic materials, biomaterials, and other products. Plasma for PECVD is typically created in various electrical discharges, e.g. DC and AC glow discharges or discharges operated at audio (10-20 kHz), radio (13.56 MHz), and microwave (2.45 GHz) frequencies. Plasma induced by a laser, a laser induced plasma (LIP), is rarely used to deposit materials from the gas phase as in PECVD. This work is aimed at reviving interest to this latter technology and showing its efficiency and potential. We run several pilot experiments. First, LIP is excited in BCl3 or BF3 plus H2 or CH4 to evaluate the efficiency of deposition of solid boron and boron carbide, the materials, which are largely used for refractory coatings. Second, we investigate a possibility of synthesis of fluorochlorosilanes SiFxCl4-x (x = 1, 2, 3) by LIP induced in SiF4 + SiCl4 gas mixtures. Using fluorochlorosilanes with different combinations of F and Cl in the SiFxCly molecule may add flexibility in processes of silicon deposition and etching. Third, LIP is excited in reactive mixture MoF6+H2+BF3 or on a Mo target ablated into H2/BF3 atmosphere. The goal is obtaining superhard molybdenum borides MoB, Mo2B, or MoB2. The gases used and solid deposits are analyzed by optical emission spectroscopy (OES), IR and mass spectrometry (MS). We also model the plasma and perform static equilibrium chemistry calculations to see if the desired reaction products are thermodynamically favorable. Dynamic calculations of the expanding plasma plume are performed using a hydrodynamic code combined with the open source chemical software. T2 - SciX 2021, The Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) CY - Providence, RI, USA DA - September 26, 2021 KW - Laser ablation KW - Laser induced plasma deposition KW - Emission spectroscopy KW - Surface coating KW - Plasma chemistry KW - Hydrodynamic model PY - 2021 AN - OPUS4-53560 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertovic, Marija T1 - NDE 4.0: Redefining Traditional Inspector Roles N2 - The successful shift to NDE 4.0 will not only require developing and embracing new technologies associated with the fourth industrial revolution or becoming an integral part of the overall Industry 4.0, but also developing and adopting new ways of working. It is undoubtful that people will remain in charge of the inspections. However, it is arguable if the current “procedure-following” “level I-III” paradigm can withstand the changes that come along NDE 4.0. With the increased autonomy and interconnectedness expected with NDT 4.0, the majority of traditional NDE tasks will no longer be needed. Instead, different skills, such as that of programming and adapting systems, as well as problem solving, will become vital for the inspections. Therefore, we suggest that a new paradigm is needed—one in which inspector roles and, thus, also the requirements will have to be reinvented. We expect the inspectors to be relieved from the tedious and error prone aspects of the current system and to take responsibility for increasingly complex automated systems and work in closer collaboration with other experts. Thus, we propose that the traditional inspector roles will be transformed into that of the system developer, caretaker and problem solver, each requiring a specific set of skills and assuming different responsibilities. In this talk, we will present the new roles and discuss the challenges that may arise with them. T2 - HOIS Digitalisation Forum (HDF) virtual seminar CY - Online meeting DA - 10.08.2021 KW - Non-Destructive Evaluation KW - NDE 4.0 KW - Human-Machine Interaction KW - Industry 4.0 KW - Inspection Personnel KW - Human-Centered Approach KW - Human Factors KW - Acceptance PY - 2021 AN - OPUS4-53549 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Bertovic, Marija A1 - Virkkunen, I. ED - Meyendorf, N. ED - Ida, N. ED - Singh, R. ED - Vrana, J. T1 - NDE 4.0: New Paradigm for the NDE Inspection Personnel N2 - Nondestructive evaluation (NDE) is entering an era of the fourth industrial revolution and will undergo a major transformation. NDE is a vital part of industry and a successful move to NDE 4.0, it will require not just developing and embracing new technologies, but also developing and adopting new ways of working and becoming an integral part of the overall Industry 4.0. This will pose new challenges for the inspection personnel. To ensure the expected benefits from NDE 4.0, inspectors need stay in charge of the changing inspections. The promised autonomy and interconnectedness of NDE 4.0 will supersede the majority of traditional inspector tasks and will in turn require a different set of skills and raise different demands and challenges for the inspection personnel, thus conflicting the current “procedure-following”-“level I-III” paradigm. The new industry 4.0 technologies can be integrated into the current framework, but exploiting their full potential requires changes in the role of the inspectors. The inspectors will be relieved from the tedious and error-prone aspects of the current system. At the same time, they will need to take responsibility for increasingly complex automated systems and work in closer collaboration with other experts. We propose that the traditional inspector roles will be transformed into that of the system developer, caretaker, and problem solver, each requiring a specific set of skills and assuming different responsibilities. For full NDE 4.0, NDE must abandon its traditional role as a self-contained entity with well-defined boundaries and take its role in the wider system that is the industry 4.0. KW - Non-Destructive Evaluation KW - NDE 4.0 KW - Industry 4.0 KW - Inspection Personnel KW - Human-Centered Approach KW - Human-Machine Interaction KW - Human Factors KW - Acceptance PY - 2021 SN - 978-3-030-48200-8 DO - https://doi.org/10.1007/978-3-030-48200-8_9-1 SP - 1 EP - 31 PB - Springer, Cham AN - OPUS4-53551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertovic, Marija T1 - NDE 4.0: Redefining Traditional Inspector Roles N2 - The successful shift to NDE 4.0 will not only require developing and embracing new technologies associated with the fourth industrial revolution or becoming an integral part of the overall Industry 4.0, but also developing and adopting new ways of working. It is undoubtful that people will remain in charge of the inspections. However, it is arguable if the current “procedure-following” “level I-III” paradigm can withstand the changes that come along NDE 4.0. With the increased autonomy and interconnectedness expected with NDT 4.0, the majority of traditional NDE tasks will no longer be needed. Instead, different skills, such as that of programming and adapting systems, as well as problem solving, will become vital for the inspections. Therefore, we suggest that a new paradigm is needed—one in which inspector roles and, thus, also the requirements will have to be reinvented. We expect the inspectors to be relieved from the tedious and error prone aspects of the current system and to take responsibility for increasingly complex automated systems and work in closer collaboration with other experts. Thus, we propose that the traditional inspector roles will be transformed into that of the system developer, caretaker and problem solver, each requiring a specific set of skills and assuming different responsibilities. In this talk, we will present the new roles and discuss the challenges that may arise with them. T2 - International Virtual Conference on NDE 4.0, DGZfP CY - Online meeting DA - 14.04.2021 KW - Non-Destructive Evaluation KW - NDE 4.0 KW - Human-Machine Interaction KW - Industry 4.0 KW - Inspection Personnel KW - Human-Centered Approach KW - Human Factors KW - Acceptance PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-535524 UR - www.ndt.net/search/docs.php3?id=26328 AN - OPUS4-53552 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - van de Kreeke, Johannes T1 - Current developments in PT N2 - This presentation was held at a laboratory conference in Colombia, and aimed at sharing some current, bigger developments with the audience that are influencing the role and impact of PT (and, to a lesser extent, RM) on labs and society. T2 - Simposio Latinoamericano de Calibracíon y Ensayos CY - Bogotá, Colombia DA - 10.11.2021 KW - Proficiency Testing KW - Reference Materials KW - COMAR KW - EPTIS PY - 2021 AN - OPUS4-53813 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 - CONF A1 - Hahn, Marc Benjamin T1 - Importance of Radiation Damage to DNA-Protein Complexes N2 - The formation of DNA-protein complexes ocurrs during replication and repair within cells. They are assumed to modify the damage caused by ionization radiation during radaition therapy. Hereby the assumption is, that the underlying damaging channels in DNA and proteins are modified, especially when compared to single molecules. T2 - Scientific online presentations workshop CY - Online meeting DA - 03.12.2021 KW - DNA KW - Proteins KW - Radiation damage KW - Ionizing radiation KW - Hydroxyl radicals PY - 2021 AN - OPUS4-53894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Roesch, Philipp A1 - Vogel, Christian A1 - Huthwelker, T. A1 - Wittwer, Philipp A1 - Simon, Franz-Georg T1 - Investigation of per‑ and polyfluoroalkyl substances (PFAS) in soils and sewage sludges by fluorine K‑edge XANES spectroscopy and combustion ion chromatography N2 - For the first time, fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy was applied to detect per- and polyfluoroalkyl substances (PFAS) in various soil and sewage sludge samples. The method can be used to determine the speciation of inorganic and organic fluorides, without pre-treatment of solid samples. Therefore, XANES spectra of several inorganic fluorides as well as selected fluorinated organic compounds were recorded. While inorganic fluorides partially exhibit a variety of sharp spectral features in the XANES spectrum, almost all inspected organofluorine compounds show two distinct broad features at 688.5 and 692.0 eV. Moreover, the peak intensity ratio 688.5 eV/692.0 eV in the PFAS XANES spectrum can be inversely correlated to the chain length of the perfluoro sulfonic acid group. The detection of targeted PFAS by bulk-XANES spectroscopy in combination with linear combination fitting in soils and sewage sludges was not applicable due to the low organic fluorine to total fluorine ratio of the samples (0.01–1.84%). Nonetheless, direct analysis of pure PFAS revealed that analysis of organofluorine species might be achieved in higher concentrated samples. Furthermore, quantitative measurements by combustion ion chromatography (CIC) evaluated as sum parameters extractable organically bound fluorine (EOF) and total fluorine (TF) emphasize that besides soils, sewage sludges are a significant source of organic fluorine in agriculture (154–7209 μg/kg). KW - Sewage sludge KW - Combustion ion chromatography KW - Oil KW - X-ray absorption near-edge structure (XANES) spectroscopy KW - Per- and polyfluoroalkyl substances (PFAS) PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538953 DO - https://doi.org/10.1007/s11356-021-17838-z VL - 29 IS - 18 SP - 26889 EP - 26899 PB - Springer AN - OPUS4-53895 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gottlieb, C. T1 - Optimization of LIBS experiments using Design of experiment (DoE) N2 - To conduct a reliable, repeatable and accurate LIBS analysis, the optimization of the experimental setup is an important task. Hardware parameters of lasers and spectrometers used in the setup as well as additionally required components such as optics or process gas pipes must be carefully aligned and adjusted because factors like (i) focal conditions of the optics, (ii) alignment of the sample, (iii) process purge gas (types, flow rate) or (iv) measurement settings (integration time, accumulation of pulses) have a big impact on the signal quality. Therefore, in most cases the effect of different factors is evaluated empirically due to changing one factor at a time while keeping the overall configuration the same. In the end, the optimal configuration is selected based on the best parameters for each influencing factor. During optimization, a configuration of the experimental setup is aimed at, which allows e.g. the highest signal intensity or the lowest variation. In most cases, cross-correlation, interference and interaction among the various factors are not considered. For this reason, the possibilities of using Design of Experiment (DoE) to optimize a LIBS experiment will be shown and advantages of (i) reduction of testing plans using a feature space, (ii) identifying and considering cross-correlations and interactions, (iii) evaluating individual impacts on the measurement (e.g. contour and surface plots) as well as (iv) multivariate models for prediction of impacts will be presented. T2 - 11th Euro-Mediterranean Symposium on Laser-Induced Breakdown Spectroscopy (EMSLIBS) CY - Online meeting DA - 29.11.2021 KW - LIBS KW - Chlorine KW - DoE PY - 2021 AN - OPUS4-53899 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gornushkin, Igor B. T1 - Laser dielectric breakdown as a novel method for producing molybdenum borides N2 - Superhard materials with a Vickers hardness in the range of 30-40 GPa are of great interest, both from a fundamental and a practical viewpoints, since they have outstanding mechanical, thermal and chemical properties. Molybdenum borides belong to this group of materials. A review of publications on synthesis of molybdenum boride indicates a) great interest in this superhard material and b) the need for new effective methods of its synthesis, especially in a nanocrystalline form. Very promising are the plasma-chemical methods based on laser induced breakdown. The breakdown can be created either in reactive gases containing volatile compounds of boron and molybdenum or on solid samples. For gas breakdown, molybdenum hexafluoride MoF6 and boron trifluoride BF3 were used in the mixture with hydrogen and argon; for solid breakdown, the pure molybdenum sample was ablated into the mixture of H2 and BF3. The plasma-chemical synthesis of MoxBy structures was carried out in the reactor shown in Figure. Laser breakdown was created by a pulsed Nd: YAG laser operating at 1064 nm with a 15 ns pulse duration, 5 Hz repetition rate, and 800 mJ pulse energy. The laser was focused by a 5 cm focal length lens to produce 26 J/cm3 energy density in the focal point. The ratios H2:BF3: MoF6 = 5:2:1 and H2:BF3 = 3:1 were used in a pressure range 30 - 760 Torr. After ablation in the mixture H2 + BF3 + MoF6, the deposit contained an amorphous phase with a small impurity of crystalline molybdenum and no boride phase. After ablation of metallic Mo into H2 + BF3, the main phase was MoB2 in the form of nano dispersed powder with an average grain size of 100 nm. The degree of conversion of boron trifluoride and the yield of molybdenum boride were studied as a function of pressure. It was established that 30 Torr is optimal for the formation of MoB2. This work was supported by the Russian Science Foundation grant No. 20-13-00035. T2 - Euro-Mediterranean Symposium on Laser-Induced Breakdown Spectroscopy CY - Online meeting DA - 29.11.2021 KW - Plasma enhanced chemical deposition KW - Laser induced plasma KW - Plasma chemistry KW - Molybdenum boride PY - 2021 AN - OPUS4-53901 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Aßmann, Norman A1 - Bühling, Benjamin T1 - Impact-echo dataset "Radarplatte" N2 - This dataset contains raw data resulting from Impact-Echo measurements at the reference conrete block "Radarplatte", located at BAM (German Federal Institute for Materials Research and Testing). This specimen has been described in detail by Niederleithinger et al. (2021), who applied muon tomography, ultrasonic echo measurements, radar and X-ray laminography to visualize its internal structure. The Impact-Echo method is based on the excitation of the zero-group-velocity frequency of the first symmetric Lamb mode of a plate-like structure, in order to assess its thickness. Numerous publication elaborate on Impact-Echo theory, examples are (Gibson and Popovics 2005, Schubert and Köhler 2008 , Abraham and Popovics 2010). The measurements have been conducted using a setup that contains only commercially available components. The setup consists of an Olson CTG-2 concrete thickness gauge (Olsen Instruments, USA) for actuation and sensing and an 8-bit NI USB-5132 digital storage oscilloscope (National Instruments, USA) combined with the Echolyst software (Schweizerischer Verein für technische Inspektionen (SVTI), Switzerland) for data acquisition. Measurements were conducted using a grid of 23x23 points with a spacing of 50 mm. At each point 8192 samples were recorded at a sampling rate of 1 MS/s. The dataset contains the (X,Y) location in mm of the individual measurement points as well as the raw measurement data at those points. The data is provided in the formats *.mir/*.mhdr (Echolyst), *.npy (Python) and *.mat (Matlab) and *.csv to ease the import in various post-processing tools. KW - Nondestructive testing KW - Impact-echo KW - S1-ZGV mode KW - Concrete PY - 2021 DO - https://doi.org/10.7910/DVN/UNOH2U PB - Harvard College CY - Cambridge, MA, USA AN - OPUS4-53886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meermann, Björn T1 - Elemental Analysis Methods in Material- & Environmental Analysis N2 - Materials in contact with the environment release e.g., metal-ions, elemental species and/or (nano-)particles. Once these species and/or particles are released, they are ingested by organisms and cells and thus, might have a negative impact on the environment. Thus, identification as well as quantification of potentially harmful substances is of utmost importance and highly needed to assess ecotoxicological impact of (emerging) pollutants. The oral presentation provides an overview on the power of elemental analytical techniques, in particular ICP-MS as well as HR-CS-GFMAS in environmental research. Current research topics from Division 1.1 @ BAM - Inorganic trace analysis will be highlighted: i) Elemental Speciation & Isotope analysis - new tools: Among elemental species separation and quantification, one of the main challenges in environmental elemental speciation analysis is the distinction between anthropogenic and natural elemental species. The on-line combination of elemental speciation and isotope analysis combines “the best from both worlds” - species specific isotopic information becomes available. As an application example the analysis of current anti-fouling agents via CE/MCICP-MS will be highlighted. ii) HR-CS-GFMAS for PFC analysis: Per- and polyfluorinated compounds (PFC) are emerging contaminants in particular in soil and surface water samples. Due to the large number of compounds (>4700), target analytical methods are not sufficient and sum parameter methods for organically bound fluorine are highly needed. High resolution-continuum source-graphite furnace molecular absorption spectroscopy (HR-CS-GFMAS) based methods for organically bound fluorine analysis will be presented. Application examples (soil and surface water) will be highlighted. iii) Single cell-ICP-ToF-MS - ecotox. assessment: Single cell and single organism analysis for e.g. ecotoxicological/medicinal assessment are hot topics in the research field of ICP-MS. In particular ICP-ToF-MS is a powerful, emerging techniques in terms of single cell/particle analysis. Automated single cell/diatom-ICP-ToF-MS as a potential tool in ecotoxicological testing will be presented. T2 - Eingeladener Fachvortrag Kolloquium AG Bleiner - EMPA CY - Online meeting DA - 03.11.2021 KW - HR-CS-GFMAS KW - SC-ICP-ToF-MS KW - Speciation analysis PY - 2021 AN - OPUS4-53707 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lee, P.-W. A1 - Kaynak, T. A1 - Al-Sabbagh, Dominik A1 - Emmerling, Franziska A1 - Schalley, C. T1 - Effect of Perfluorinated Side-Chain Length on the Morphology, Hydrophobicity, and Stability of Xerogel Coatings N2 - Superhydrophobic surfaces can be quickly formed with supramolecular materials. Incorporating low-molecular-weight gelators (LMWGs) with perfluorinated chains generates xerogel coatings with low surface energies and high roughness. Here, we examine and compare the properties of the xerogel coatings formed with eight different LMWGs. These LMWGs all have a trans-1,2-diamidocyclohexane core and two perfluorinated ponytails, whose lengths vary from three to ten carbon atoms (CF3 to CF10). Investigation of the xerogels aims to provide in-depth information on the chain length effect. LMWGs with a higher degree of fluorination (CF7 to CF10) form superhydrophobic xerogel coatings with very low surface energies. Scanning electron microscopy images of the coatings show that the aggregates of CF5 and CF7 are fibrous, while the others are crystal-like. Aggregates of CF10 are particularly small and further assemble into a porous structure on the micrometer scale. To test their stabilities, the xerogel coatings were flushed multiple times with a standardized water flush test. The removal of material from the surface in these flushes was monitored by a combination of the water contact angle, contact angle hysteresis, and coating thickness measurements. A new method based on image processing techniques was developed to reliably determine the change of the coating thickness. The CF7, CF9, and CF10 surfaces show consistent hydrophobicity and coating durability after repetitive flushing tests. The length of the perfluorinated side chains thus has a significant effect on the morphology of the deposited xerogel coatings, their roughness, and, in consequence, their hydrophobicity and mechanical durability. KW - Coating materials KW - Amorphous materials KW - Hydrophobicity KW - Materials Stability PY - 2021 DO - https://doi.org/10.1021/acs.langmuir.1c02341 SN - 1520-5827 VL - 37 IS - 49 SP - 14390 EP - 14397 PB - ACS Publications AN - OPUS4-54071 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Van Den Bossche, T. A1 - Kunath, B. A1 - Schallert, K. A1 - Schäpe, S. A1 - Abraham, P. E. A1 - Armengaud, J. A1 - Arntzen, M. Ø. A1 - Bassignani, A. A1 - Benndorf, D. A1 - Fuchs, S. A1 - Giannone, R. J. A1 - Griffin, T. J. A1 - Hagen, L. H. A1 - Halder, R. A1 - Henry, C. A1 - Hettich, R. L. A1 - Heyer, R. A1 - Jagtap, P. A1 - Jehmlich, N. A1 - Jensen, M. A1 - Juste, C. A1 - Kleiner, M. A1 - Langella, O. A1 - Lehmann, T. A1 - Leith, E. A1 - May, P. A1 - Mesuere, B. A1 - Miotello, G. A1 - Peters, S. L. A1 - Pible, O. A1 - Queiros, P. T. A1 - Reichl, U. A1 - Renard, B. Y. A1 - Schiebenhoefer, H. A1 - Sczyrba, A. A1 - Tanca, A. A1 - Trappe, K. A1 - Trezzi, J.-P. A1 - Uzzau, S. A1 - Verschaffelt, P. A1 - von Bergen, M. A1 - Wilmes, P. A1 - Wolf, M. A1 - Martens, L. A1 - Muth, Thilo T1 - Critical Assessment of MetaProteome Investigation (CAMPI): A multi-laboratory comparison of established workflows N2 - Metaproteomics has matured into a powerful tool to assess functional interactions in microbial communities. While many metaproteomic workflows are available, the impact of method choice on results remains unclear. Here, we carry out a community-driven, multi-laboratory comparison in metaproteomics: the critical assessment of metaproteome investigation study (CAMPI). Based on well-established workflows, we evaluate the effect of sample preparation, mass spectrometry, and bioinformatic analysis using two samples: a simplified, laboratory-assembled human intestinal model and a human fecal sample. We observe that variability at the peptide level is predominantly due to sample processing workflows, with a smaller contribution of bioinformatic pipelines. These peptide-level differences largely disappear at the protein group level. While differences are observed for predicted community composition, similar functional profiles are obtained across workflows. CAMPI demonstrates the robustness of present-day metaproteomics research, serves as a template for multi-laboratory studies in metaproteomics, and provides publicly available data sets for benchmarking future developments. KW - Metaproteomics KW - Mass spectrometry KW - Data science KW - Benchmarking KW - Bioinformatics PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-541220 DO - https://doi.org/10.1038/s41467-021-27542-8 SN - 2041-1723 VL - 12 SP - 1 EP - 15 PB - Nature Publishing Group CY - London AN - OPUS4-54122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völker, Christoph T1 - Uncertainty quantification for a sparse machine learning (ML) data set in non-destructive testing in civil engineering (NDT-CE) N2 - ML has been successfully applied to solve many NDT-CE tasks. This is usually demonstrated with performance metrics that evaluate the model as a whole based on a given set of data. However, since in most cases the creation of reference data is extremely expensive, the data used is generally much sparser than in other areas, such as e-commerce. As a result, performance indicators often do not reflect the practical applicability of the ML model. Estimates that quantify transferability from one case to another are necessary to meet this challenge and pave the way for real world applications. In this contribution we invetigate the uncertainty of ML in new NDT-CE scenarios. For this purpose, we have extended an existing training data set for the classification of corrosion damage by a new case study. Our data set includes half-cell potential mapping and ground-penetrating radar measurements. The measurements were performed on large-area concrete samples with built-in chloride-induced corrosion of reinforcement. The experiment simulated the entire life cycle of chloride induced exposed concrete components in the laboratory. The unique ability to monitor deterioration and initiate targeted corrosion initiation allowed the data to be labelled - which is crucial to ML. To investigate transferability, we extend our data by including new design features of the test specimen and environmental conditions. This allows to express the change of these features in new scenarios as uncertainties using statistical methods. We compare different sampling and statistical distribution-based approaches and show how these methods can be used to close knowledge gaps of ML models in NDT. T2 - EGU General Assembly 2021 CY - Online meeting DA - 19.04.2021 KW - Data fusion KW - Non-destructive testing PY - 2021 DO - https://doi.org/10.5194/egusphere-egu21-8798 AN - OPUS4-54125 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nolze, Gert A1 - Winkelmann, A. T1 - About the reliability of EBSD measurements: Data enhancement N2 - An extensive set of information about the diffracting volume is carried by EBSD patterns: the crystal lattice, the reciprocal lattice, the crystal structure, the crystal symmetry, the mean periodic number of the diffracting phase, the source point from where it has been projected (projection centre), the crystal orientation, the sample topography (local tilt), the (preparation) quality of defect density of the crystal, and possible pattern overlaps. Some of this information is used regularly in conventional EBSD analyses software while others are still waiting for a more widespread application. Despite the wealth of information available, the accuracy and precision of the data that are presently extracted from conventional EBSD patterns are often well below the actual physical limits. Using a selection of example applications, we will demonstrate the gain in angular resolution possible using relatively low-resolution patterns of approximately 20k pixels in combination with pattern matching (PM) approaches. In this way, fine details in a microstructure can be revealed which would otherwise be hidden in the orientation noise. KW - EBSD KW - Orientation precision KW - Disorientation KW - Grain boundary KW - Phase transformation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-521618 DO - https://doi.org/10.1088/1757-899X/891/1/012018 VL - 891 SP - 012018 PB - IOP Science AN - OPUS4-52161 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herrmann, K. A1 - Pech May, Nelson Wilbur A1 - Retsch, M. T1 - Photoacoustic thermal characterization of low thermal diffusivity thin films N2 - The photoacoustic measurement technique is a powerful yet underrepresented method to characterize the thermal transport properties of thin films. For the case of isotropic low thermal diffusivity samples, such as glasses or polymers, we demonstrate a general approach to extract the thermal conductivity with a high degree of significance. We discuss in particular the influence of thermal effusivity, thermal diffusivity, and sample layer thickness on the significance and accuracy of this measurement technique. These fundamental thermal properties guide sample and substrate selection to allow for a feasible thermal transport characterization. Furthermore, our data evaluation allows us to directly extract the thermal conductivity from this transient technique, without separate determination of the volumetric heat capacity, when appropriate boundary conditions are fulfilled. Using silica, poly(methyl methacrylate) (PMMA) thin films, and various substrates (quartz, steel, and silicon), we verify the quantitative correctness of our analytical approach. KW - Thermal conductivity KW - Photoacoustic characterization KW - Thin film characterization PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528743 DO - https://doi.org/10.1016/j.pacs.2021.100246 SN - 2213-5979 VL - 22 SP - 100246 PB - Elsevier AN - OPUS4-52874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Albarrán Martínez, M. J. A1 - Ghigo, Tea T1 - The practice of writing inside an Egyptian monastic settlement N2 - Over the last few years, the Federal Institute for material research (BAM, Berlin) together with the Centre for the Study of Manuscript Cultures (CSMC, University of Hamburg) have initiated a systematic material investigation of black inks produced from Late Antiquity to the Middle Ages (ca. fourth century CE–fourteenth/fifteenth centuries CE), aimed primarily at extending and complementing findings from previous sporadic studies. Part of this systematic investigation has focused on Egyptian Coptic manuscripts, and the present preliminary study is one of its outputs. It centres on a corpus of 45 Coptic manuscripts—43 papyri and 2 ostraca—preserved at the Palau-Ribes and Roca-Puig collections in Barcelona. The manuscripts come from the Monastery of Apa Apollo at Bawit, one of the largest monastic settlements in Egypt between the Late Antiquity and the Early Islamic Period (sixth–eighth centuries CE). The composition of their black inks was investigated in situ using near-infrared reflectography (NIRR) and X-ray fluorescence (XRF). The analyses determined that the manuscripts were written using different types of ink: pure carbon ink; carbon ink containing iron; mixed inks containing carbon, polyphenols and metallic elements; and iron-gall ink. The variety of inks used for the documentary texts seems to reflect the articulate administrative system of the monastery of Bawit. This study reveals that, in contrast to the documents, written mostly with carbon-based inks, literary biblical texts were written with iron-gall ink. The frequent reuse of papyrus paper for certain categories of documents may suggest that carbon-based inks were used for ephemeral manuscripts, since they were easy to erase by abrasion. KW - Papyrus KW - Ink analysis KW - Coptic manuscripts KW - Bawit KW - Mixed ink KW - Near-infrared refectography KW - X-ray fuorescence PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528833 DO - https://doi.org/10.1186/s40494-021-00541-0 SN - 2050-7445 VL - 9 IS - 1 SP - 1 EP - 15 PB - Springer Open CY - Rome, Italy AN - OPUS4-52883 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ahmadi, Samim A1 - Lecompagnon, Julien A1 - Hirsch, Philipp Daniel A1 - Burgholzer, Peter A1 - Jung, Peter A1 - Caire, Giuseppe A1 - Ziegler, Mathias T1 - Laser excited super resolution thermal imaging for nondestructive testing N2 - The work to be presented focuses on our most recent studies to laser excited super resolution (SR) thermography. The goal of nondestructive testing with SR is to facilitate the separation of closely spaced defects. Photothermal SR can be realized by performing structured illumination measurements in com-bination with the use of deconvolution algorithms in post-processing. We explain that stepwise as well as continuous scanning techniques are applicable to generate structured illumination measurements. Finally, we discuss the effect of experimental parameters and image processing techniques to find the optimal SR technique which leads to the highest reconstruction quality within laser thermography. T2 - Sensor and Measurement Science International Conference SMSI 2021 CY - Online meeting DA - 03.05.2021 KW - Super resolution KW - Laser thermography KW - Nondestructive testing KW - Laser scanning KW - Photothermal imaging PY - 2021 SP - 181 EP - 182 AN - OPUS4-52780 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ahmadi, Samim T1 - Laser excited super resolution thermal imaging for nondestructive testing N2 - The work to be presented focuses on our most recent studies to laser excited super resolution (SR) thermography. The goal of nondestructive testing with SR is to facilitate the separation of closely spaced defects. Photothermal SR can be realized by performing structured illumination measurements in com-bination with the use of deconvolution algorithms in post-processing. We explain that stepwise as well as continuous scanning techniques are applicable to generate structured illumination measurements. Finally, we discuss the effect of experimental parameters and image processing techniques to find the optimal SR technique which leads to the highest reconstruction quality within laser thermography. T2 - Sensor and Measurement Science International Conference SMSI 2021 CY - Online meeting DA - 03.05.2021 KW - Super resolution KW - Laser thermography KW - Nondestructive testing KW - Laser scanning KW - Photothermal imaging PY - 2021 AN - OPUS4-52781 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lugovtsova, Yevgeniya A1 - Bulling, Jannis A1 - Mesnil, O. A1 - Prager, Jens A1 - Gohlke, Dirk A1 - Boller, C. T1 - Damage quantification in an aluminium-CFRP composite structure using guided wave wavenumber mapping: Comparison of instantaneous and local wavenumber analyses N2 - Composite-overwrapped pressure vessels (COPV) are increasingly used in the transportation industry due to their high strength to mass ratio. Throughout the years, various designs were developed and found their applications. Currently, there are five designs, which can be subdivided into two main categories - with a load-sharing metal liner and with a non-load-sharing plastic liner. The main damage mechanism defining the lifetime of the first type is fatigue of the metal liner, whereas for the second type it is fatigue of the composite overwrap. Nevertheless, one damage type which may drastically reduce the lifetime of COPV is impact-induced damage. Therefore, this barely visible damage needs to be assessed in a non-destructive way to decide whether the pressure vessel can be further used or has to be put out of service. One of the possible methods is based on ultrasonic waves. In this contribution, both conventional ultrasonic testing (UT) by high-frequency bulk waves and wavenumber mapping by low frequency guided waves are used to evaluate impact damage. Wavenumber mapping techniques are first benchmarked on a simulated aluminium panel then applied to experimental measurements acquired on a delaminated aluminium-CFRP composite plate which corresponds to a structure of COPV with a load-sharing metal liner. The analysis of experimental data obtained from measurements of guided waves propagating in an aluminium-CFRP composite plate with impact-induced damage is performed. All approaches show similar performance in terms of quantification of damage size and depths while being applied to numerical data. The approaches used on the experimental data deliver an accurate estimate of the in-plane size of the large delamination at the aluminium-CFRP interface but only a rough estimate of its depth. Moreover, none of the wavenumber mapping techniques used in the study can quantify every delamination between CFRP plies caused by the impact, which is the case for conventional UT. This may be solved by using higher frequencies (shorter wavelengths) or more advanced signal processing techniques. All in all, it can be concluded that imaging of complex impact damage in fibre-reinforced composites based on wavenumber mapping is not straightforward and stays a challenging task. KW - Ultrasonic guided waves KW - Instantaneous wavenumber analysis KW - Local wavenumber analysis KW - Signal processing PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528203 DO - https://doi.org/10.1016/j.ndteint.2021.102472 SN - 0963-8695 VL - 122 SP - 2472 PB - Elsevier Ltd. CY - Amsterdam, Netherlands AN - OPUS4-52820 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tschöke, K. A1 - Müller, I. A1 - Memmolo, V. A1 - Moix-Bonet, M. A1 - Moll, J. A1 - Lugovtsova, Yevgeniya A1 - Golub, M. A1 - Sridaran Venkat, R. A1 - Schubert, L. T1 - Feasibility of Model-Assisted Probability of Detection Principles for Structural Health Monitoring Systems based on Guided Waves for Fibre-Reinforced Composites N2 - In many industrial sectors, Structural Health Monitoring (SHM) is considered as an addition to Non-Destructive Testing (NDT) that can reduce maintenance effort during lifetime of a technical facility, structural component or vehicle. A large number of SHM methods is based on ultrasonic waves, whose properties change depending on structural health. However, the wide application of SHM systems is limited due to the lack of suitable methods to assess their reliability. The evaluation of the system performance usually refers to the determination of the Probability of Detection (POD) of a test procedure. Up to now, only few limited methods exist to evaluate the POD of SHM systems, which prevent them from being standardised and widely accepted in industry. The biggest hurdle concerning the POD calculation is the large amount of samples needed. A POD analysis requires data from numerous identical structures with integrated SHM systems. Each structure is then damaged at different locations and with various degrees of severity. All of this is connected to high costs. Therefore, one possible way to tackle this problem is to perform computer-aided investigations. In this work, the POD assessment procedure established in NDT according to the Berens model is adapted to guided wave-based SHM systems. The approach implemented here is based on solely computer-aided investigations. After efficient modelling of wave propagation phenomena across an automotive component made of a carbon fibre-reinforced composite, the POD curves are extracted. Finally, the novel concept of a POD map is introduced to look into the effect of damage position on system reliability. KW - Reliability KW - Acoustics KW - Monitoring KW - Automotive engineering KW - Elastodynamic Finite Inegration Technique PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528218 DO - https://doi.org/10.1109/TUFFC.2021.3084898 VL - 68 IS - 10 SP - 3156 EP - 3173 AN - OPUS4-52821 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 - CONF A1 - Casperson, Ralf T1 - Non-Destructive Testing of Composite Pressure Vessels using Conventional and High-Frequency Eddy Current Technique N2 - Pressure vessels for the transport of hazardous gases are subjected to a hydraulic internal pressure test. Basis for the design of metallic pressure vessels is the fatigue strength according to Wöhler, whereby the number of load changes can be equated with the number of filling / emptying cycles of the pressure vessel. Metallic pressure vessels are increasingly replaced by composite pressure vessels due to the weight savings. However, at composite preasure vessels it is not possible to conclude from the number of load cycles on the fatigue strength, because composite pressure vessels are ageing even at constant internal pressure. Non-destructive conventional and high frequency eddy current testing of the metallic liner and load bearing CFRP layer are presented as an alternative to hydraulic internal pressure test. T2 - TAHYA Workshop CY - Online meeting DA - 02.06.2021 KW - Non-destructive testing KW - Composite preasure vessel KW - Eddy currnet testing PY - 2021 AN - OPUS4-52856 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meermann, Björn T1 - HR-CS-GFMAS as a promising new tool for the analysis of organo-fluorine in environmental samples N2 - New HR-CS-GFMAS based methods for organically bound fluorine detection in environmental samples. T2 - CRC Colloquium - CRC 1349 Fluorine-Specific Interactions CY - Online meeting DA - 21.06.2021 KW - HR-CS-GFMAS KW - Organically bound fluorine KW - Fluorine sum parameter KW - Environmental analysis PY - 2021 AN - OPUS4-52844 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simões, R. G. A1 - Melo, P. L. T. A1 - Bernardes, C. E. S. A1 - Heilmann, Maria A1 - Emmerling, Franziska A1 - Minas da Piedade, M. E. T1 - Linking Aggregation in Solution, Solvation, and Solubility of Simvastatin: An Experimental and MD Simulation Study N2 - The solubility is generally thought to be higher if the solvent effectively solvates solute molecules that are well-separated from each other. The present work suggests, however, that the formation of large solute aggregates does not necessarily imply less effective solvation and lower solubility. Measurements of the solubility of simvastatin (one of the most commonly prescribed antihyperlipidemic drugs) in three solvents with different polarities and protic characters, led to the solubility order acetone > ethyl acetate > ethanol, in the full temperature range covered by the experiments (283–308 K). An analysis of the structures of the different solutions on the basis of molecular dynamics simulation results indicated that this trend seems to be determined by a balance between the solute tendency toward aggregation and the ability of the solvent to efficiently solvate it, by integrating the cluster structures, regardless of their size, and effectively establishing solvent–solute interactions. KW - Simvastatin KW - Solubility KW - API KW - Aggregation PY - 2021 DO - https://doi.org/10.1021/acs.cgd.0c01325 VL - 21 IS - 1 SP - 544 EP - 551 AN - OPUS4-52185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thinnes, A. A1 - Westenberger, M. A1 - Piechotta, Christian A1 - Letho, L. A1 - Wirth, F. A1 - Lau, H. A1 - Klein, J. T1 - Cholinergic and metabolic effects of metformin in mouse brain N2 - Metformin is widely used as a first-line treatment for type 2 diabetes, but central effects of metformin have received little attention. When metformin (200 mg/kg i.p.) was administered to C57Bl6 mice, metformin concentration in cerebrospinal fluid peaked at 29 μM after 30 min but dropped quickly and was low at 90 min. In mouse hypothalamus sampled by microdialysis, systemically administered metformin caused minor and transient increases of acetylcholine, glucose and lactate while choline levels decreased. When metformin (0.2−10 mM) was locally infused via retrodialysis, there was a short-lasting increase of acetylcholine in the hypothalamus. Extracellular lactate levels in hypothalamus showed a massive increase upon metformin infusion while glucose levels decreased. In isolated mitochondria of mouse brain, metformin inhibited oxygen consumption and the activity of complex I. Inhibition of mitochondrial respiration likely explains lactate formation in the brain during metformin infusion which may cause lactic acidosis during metformin intoxication. The changes of cholinergic activity in the hypothalamus may be associated with appetite suppression observed during metformin treatment. KW - Metformin KW - Blood-brain barrier KW - Lactate KW - Glucose KW - Microdialysis KW - Hypothalamus PY - 2021 DO - https://doi.org/10.1016/j.brainresbull.2021.02.018 SN - 0361-9230 VL - 170 SP - 211 EP - 217 PB - Elsevier CY - Amsterdam, Niederlande AN - OPUS4-52189 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adams, L. C. A1 - Brangsch, J. A1 - Kaufmann, Jan Ole A1 - Mangarova, D. B. A1 - Moeckel, J. A1 - Kader, A. A1 - Buchholz, R. A1 - Karst, U. A1 - Botnar, R. M. A1 - Hamm, B. A1 - Makowski, M. R. A1 - Keller, S. T1 - Effect of Doxycycline on Survival in Abdominal Aortic Aneurysms in a Mouse Model N2 - Background. Currently, there is no reliable nonsurgical treatment for abdominal aortic aneurysm (AAA). This study, therefore, investigates if doxycycline reduces AAA growth and the number of rupture-related deaths in a murine ApoE−/− model of AAA and whether gadofosveset trisodium-based MRI differs between animals with and without doxycycline treatment. Methods. Nine ApoE−/− mice were implanted with osmotic minipumps continuously releasing angiotensin II and treated with doxycycline (30 mg/kg/d) in parallel. After four weeks, MRI was performed at 3T with a clinical dose of the albumin-binding probe gadofosveset (0.03 mmol/kg). Results were compared with previously published wild-type control animals and with previously studied ApoE−/− animals without doxycycline treatment. Differences in mortality were also investigated between these groups. Results. In a previous study, we found that approximately 25% of angiotensin II-infused ApoE−/− mice died, whereas in the present study, only one out of 9 angiotensin II-infused and doxycycline-treated ApoE−/− mice (11.1%) died within 4 weeks. Furthermore, doxycycline-treated ApoE−/− mice showed significantly lower contrast-to-noise (CNR) values in MRI compared to ApoE−/− mice without doxycycline treatment. In vivo measurements of relative signal enhancement (CNR) correlated significantly with ex vivo measurements of albumin staining (R2 = 0.58). In addition, a strong visual colocalization of albumin-positive areas in the fluorescence albumin staining with gadolinium distribution in LA-ICP-MS was shown. However, no significant difference in aneurysm size was observed after doxycycline treatment. Conclusion. The present experimental in vivo study suggests that doxycycline treatment may reduce rupture-related deaths in AAA by slowing endothelial damage without reversing aneurysm growth. KW - Ggadolinium KW - MRI KW - Magnetic resonance imaging KW - Osmotic minipumps KW - Tetracyclin KW - Antibiotics KW - Angiotensin II KW - LA-ICP-MS PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-527015 DO - https://doi.org/10.1155/2021/9999847 SP - 9999847 PB - Hindawi CY - London AN - OPUS4-52701 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -