TY - JOUR A1 - Knabe, Christine A1 - Adel-Khattab, Doaa A1 - Rezk, Mohamed A1 - Cheng, Jia A1 - Berger, Georg A1 - Gildenhaar, Renate A1 - Wilbig, Janka A1 - Günster, Jens A1 - Rack, Alexander A1 - Heiland, Max A1 - Knauf, Tom A1 - Stiller, Michael T1 - Osteogenic Effect of a Bioactive Calcium Alkali Phosphate Bone Substitute in Humans N2 - (1) Background: The desire to avoid autograft harvesting in implant dentistry has prompted an ever-increasing quest for bioceramic bone substitutes, which stimulate osteogenesis while resorbing in a timely fashion. Consequently, a highly bioactive silicon containing calcium alkali orthophosphate (Si-CAP) material was created, which previously was shown to induce greater bone cell maturation and bone neo-formation than β-tricalcium phosphate (β-TCP) in vivo as well as in vitro. Our study tested the hypothesis that the enhanced effect on bone cell function in vitro and in sheep in vivo would lead to more copious bone neoformation in patients following sinus floor augmentation (SFA) employing Si-CAP when compared to β-TCP. (2) Methods: The effects of Si-CAP on osteogenesis and Si-CAP resorbability were evaluated in biopsies harvested from 38 patients six months after SFA in comparison to β-TCP employing undecalcified histology, histomorphometry, and immunohistochemical analysis of osteogenic marker expression. (3) Results: Si-CAP as well as β-TCP supported matrix mineralization and bone formation. Apically furthest away from the original bone tissue, Si-CAP induced significantly higher bone formation, bone-bonding (bone-bioceramic contact), and granule resorption than β-TCP. This was in conjunction with a higher expression of osteogenic markers. (4) Conclusions: Si-CAP induced higher and more advanced bone formation and resorbability than β-TCP, while β-TCP’s remarkable osteoconductivity has been widely demonstrated. Hence, Si-CAP constitutes a well-suited bioactive graft choice for SFA in the clinical arena. KW - Silicon release KW - Bioceramics KW - Calcium alkali orthophosphate materials KW - Bioactive bone grafting material KW - Bioactivity KW - Osteogenesis KW - Bone regeneration KW - Sinus floor augmentation PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591015 DO - https://doi.org/10.3390/bioengineering10121408 VL - 10 IS - 12 SP - 1 EP - 15 PB - MDPI AN - OPUS4-59101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reuter, T. A1 - Borges de Oliveira, F. A1 - Abt, Ch. A1 - Ballach, F. A1 - Bartscher, M. A1 - Bellon, Carsten A1 - Dennerlein, F. A1 - Fuchs, P. A1 - Günnewig, O. A1 - Hausotte, T. A1 - Hess, J. A1 - Kasperl, S. A1 - Maass, N. A1 - Kimmig, W. A1 - Schielein, R. A1 - von Schmid, M. A1 - Suppes, A. A1 - Wagner, G. A1 - Watzl, Ch. A1 - Wohlgemuth, F. T1 - Introduction to “Realistic Simulation of real CT systems with a basic-qualified Simulation Software - CTSimU2“ N2 - The lack of traceability to meter of X-ray Computed Tomography (CT) measurements still hinders a more extensive acceptance of CT in coordinate metrology and industry. To ensure traceable, reliable, and accurate measurements, the determination of the task-specific measurement uncertainty is necessary. The German guideline VDI/VDE 2630 part 2.1 describes a procedure to determine the measurement uncertainty for CT experimentally by conducting several repeated measurements with a calibrated test specimen. However, this experimental procedure is cost and effort intensive. Therefore, the simulation of dimensional measurement tasks conducted with X-ray computed tomography can close these drawbacks. Additionally, recent developments towards a resource and cost-efficient production (“smart factory”) motivate the need for a corresponding numerical model of a CT system (“digital twin”) as well. As there is no standardized procedure to determine the measurement uncertainty of a CT system by simulation at the moment, the project series CTSimU was initiated, aiming at this gap. Concretely, the goal is the development of a procedure to determine the measurement uncertainty numerically by radiographic simulation. The first project (2019-2022), "Radiographic Computed Tomography Simulation for Measurement Uncertainty Evaluation - CTSimU" developed a framework to qualify a radiographic simulation software concerning the correct simulation of physical laws and functionalities. The most important outcome was a draft for a new guideline VDI/VDE 2630 part 2.2, which is currently under discussion in the VDI/VDE committee. The follow-up project CTSimU2 "Realistic Simulation of real CT systems with a basic-qualified Simulation Software" will deal with building and characterizing a digital replica of a specific real-world CT system. The two main targets of this project will be a toolbox including methods and procedures to configure a realistic CT system simulation and to develop tests to check if this replica is sufficient enough. The result will be a draft for a follow-up VDI/VDE guideline proposing standardized procedures to determine a CT system's corresponding characteristics and test the simulation (copy) of a real-world CT system which we call a "digital twin". T2 - 12th Conference on Industrial Computed Tomography (iCT) 2023 CY - Fürth, Germany DA - 27.02.2023 KW - dXCT KW - X-ray computed tomography KW - Simulation PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589204 DO - https://doi.org/10.58286/27715 VL - 28 IS - 3 SP - 1 EP - 5 PB - NDT.net AN - OPUS4-58920 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Linberg, Kevin A1 - Szymoniak, Paulina A1 - Schönhals, Andreas A1 - Emmerling, Franziska A1 - Michalchuk, Adam A. L. T1 - The Origin of Delayed Polymorphism in Molecular Crystals Under Mechanochemical Conditions N2 - We show that mechanochemically driven polymorphic transformations can require extremely long induction periods, which can be tuned from hours to days by changing ball milling energy. The robust design and interpretation of ball milling experiments must account for this unexpected kinetics that arises from energetic phenomena unique to the solid state. Detailed thermal analysis, combined with DFT simulations, indicates that these marked induction periods are associated with processes of mechanical activation. Correspondingly, we show that the pre‐activation of reagents can also lead to marked changes in the length of induction periods. Our findings demonstrate a new dimension for exerting control over polymorphic transformations in organic crystals. We expect mechanical activation to have a much broader implication across organic solid‐state mechanochemistry. KW - General Chemistry KW - Catalysis KW - Organic Chemistry PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589219 DO - https://doi.org/10.1002/chem.202302150 SN - 0947-6539 SP - e202302150 PB - Wiley AN - OPUS4-58921 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Edzards, Joshua A1 - Saßnick, Holger-Dietrich A1 - Buzanich, Ana Guilherme A1 - Valencia, Ana M. A1 - Emmerling, Franziska A1 - Beyer, Sebastian A1 - Cocchi, Caterina T1 - Effects of Ligand Substituents on the Character of Zn-Coordination in Zeolitic Imidazolate Frameworks N2 - Due to their favorable properties and high porosity, zeolitic imidazolate frameworks (ZIFs) have recently received much limelight for key technologies such as energy storage, optoelectronics, sensorics, and catalysis. Despite widespread interest in these materials, fundamental questions regarding the zinc coordination environment remain poorly understood. By focusing on zinc(II)2-methylimidazolate (ZIF-8) and its tetrahedrally coordinated analogues with Br-, Cl-, and H-substitution in the 2-ring position, we aim to clarify how variations in the local environment of Zn impact the charge distribution and the electronic properties of these materials. Our results from densityfunctional theory confirm the presence of a Zn coordinative bond with a large polarization that is quantitatively affected by different substituents on the organic ligand. Moreover, our findings suggest that the variations in the Zn coordination induced by the functionalization have a negligible effect on the electronic structure of the considered compounds. On the other hand, halogen terminations of the ligands lead to distinct electronic contributions in the vicinity of the frontier region which ultimately reduce the band gap size by a few hundred millielectron volts. Experimental results obtained from X-ray absorption spectroscopy (Zn K-edge) confirm the trends predicted by theory and, together with them, contribute to a better understanding of the structure−property relationships that are needed to tailor ZIFs for target applications. KW - Surfaces KW - Physical and Theoretical Chemistry KW - General Energy KW - Electronic KW - Coatings and Films KW - Optical and Magnetic Materials PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589117 DO - https://doi.org/10.1021/acs.jpcc.3c06054 SN - 1932-7447 VL - 127 IS - 43 SP - 21456 EP - 21464 PB - American Chemical Society (ACS) AN - OPUS4-58911 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erler, A. A1 - Riebe, D. A1 - Beitz, T. A1 - Löhmannsröben, H.-G. A1 - Leenen, M. A1 - Pätzold, S. A1 - Ostermann, Markus A1 - Wójcik, M. T1 - Mobile Laser-Induced Breakdown Spectroscopy for Future Application in Precision Agriculture—A Case Study N2 - In precision agriculture, the estimation of soil parameters via sensors and the creation of nutrient maps are a prerequisite for farmers to take targeted measures such as spatially resolved fertilization. In this work, 68 soil samples uniformly distributed over a field near Bonn are investigated using laser-induced breakdown spectroscopy (LIBS). These investigations include the determination of the total contents of macro- and micronutrients as well as further soil parameters such as soil pH, soil organic matter (SOM) content, and soil texture. The applied LIBS instruments are a handheld and a platform spectrometer, which potentially allows for the single-point measurement and scanning of whole fields, respectively. Their results are compared with a high-resolution lab spectrometer. The prediction of soil parameters was based on multivariate methods. Different feature selection methods and regression methods like PLS, PCR, SVM, Lasso, and Gaussian processes were tested and compared. While good predictions were obtained for Ca, Mg, P, Mn, Cu, and silt content, excellent predictions were obtained for K, Fe, and clay content. The comparison of the three different spectrometers showed that although the lab spectrometer gives the best results, measurements with both field spectrometers also yield good results. This allows for a method transfer to the in-field measurements KW - LIBS KW - Precision agriculture KW - Soil KW - Multivariate methods KW - Feature selection PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580777 DO - https://doi.org/10.3390/s23167178 VL - 23 IS - 16 SP - 1 EP - 17 PB - MDPI AG CY - Basel, Schweiz AN - OPUS4-58077 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Arikan, Muzaffer A1 - Muth, Thilo T1 - Integrated multi-omics analyses of microbial communities: A review of the current state and future directions N2 - Integrated multi-omics analyses of microbiomes have become increasingly common in recent years as the emerging omics technologies provide an unprecedented opportunity to better understand the structural and functional properties of microbial communities. Consequently, there is a growing need for and interest in the concepts, approaches, considerations, and available tools for investigating diverse environmental and host-associated microbial communities in an integrative manner. In this review, we first provide a general overview of each omics analysis type, including a brief history, typical workflow, primary applications, strengths, and limitations. Then, we inform on both experimental design and bioinformatics analysis considerations in integrated multi-omics analyses, elaborate on the current approaches and commonly used tools, and highlight the current challenges. Finally, we discuss the expected key advances, emerging trends, potential implications on various fields from human health to biotechnology, and future directions. KW - Microbiome KW - Multi-omics KW - Data integration PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580785 DO - https://doi.org/10.1039/d3mo00089c SP - 1 EP - 17 PB - Royal Society of Chemistry AN - OPUS4-58078 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Walke, D. A1 - Micheel, D. A1 - Schallert, K. A1 - Muth, Thilo A1 - Broneske, D. A1 - Saake, G. A1 - Heyer, R. T1 - The importance of graph databases and graph learning for clinical applications N2 - The increasing amount and complexity of clinical data require an appropriate way of storing and analyzing those data. Traditional approaches use a tabular structure (relational databases) for storing data and thereby complicate storing and retrieving interlinked data from the clinical domain. Graph databases provide a great solution for this by storing data in a graph as nodes (vertices) that are connected by edges (links). The underlying graph structure can be used for the subsequent data analysis (graph learning). Graph learning consists of two parts: graph representation learning and graph analytics. Graph representation learning aims to reduce high-dimensional input graphs to low-dimensional representations. Then, graph analytics uses the obtained representations for analytical tasks like visualization, classification, link prediction and clustering which can be used to solve domain-specific problems. In this survey, we review current state-of-the-art graph database management systems, graph learning algorithms and a variety of graph applications in the clinical domain. Furthermore, we provide a comprehensive use case for a clearer understanding of complex graph learning algorithms. KW - Graph databases KW - Graph learning KW - Review KW - RDF PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580858 DO - https://doi.org/10.1093/database/baad045 SN - 1758-0463 SP - 1 EP - 20 AN - OPUS4-58085 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Raute, J. A1 - Biegler, M. A1 - Rethmeier, Michael T1 - Process Setup and Boundaries of Wire Electron Beam Additive Manufacturing of High-Strength Aluminum Bronze N2 - In recent years, in addition to the commonly known wire-based processes of Directed Energy Deposition using lasers, a process variant using the electron beam has also developed to industrial market maturity. The process variant offers particular potential for processing highly conductive, reflective or oxidation-prone materials. However, for industrial usage, there is a lack of comprehensive data on performance, limitations and possible applications. The present study bridges the gap using the example of the high-strength aluminum bronze CuAl8Ni6. Multi-stage test welds are used to determine the limitations of the process and to draw conclusions about the suitability of the parameters for additive manufacturing. For this purpose, optimal ranges for energy input, possible welding speeds and the scalability of the process were investigated. Finally, additive test specimens in the form of cylinders and walls are produced, and the hardness profile, microstructure and mechanical properties are investigated. It is found that the material CuAl8Ni6 can be well processed using wire electron beam additive manufacturing. The microstructure is similar to a cast structure, the hardness profile over the height of the specimens is constant, and the tensile strength and elongation at fracture values achieved the specification of the raw material. KW - Wire electron beam additive manufacturing KW - Aluminum bronze KW - Wire-based additive manufacturing KW - EBAM KW - DED-EB PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580890 DO - https://doi.org/10.3390/met13081416 VL - 13 IS - 8 SP - 1 EP - 16 PB - MDPI AN - OPUS4-58089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Even, Morgane A1 - Juritsch, Elevtheria A1 - Richter, Matthias T1 - On the use of Carbograph 5TD as an adsorbent for sampling VVOCs: validation of an analytical method N2 - A standardised method for the analysis of very volatile organic compounds (VVOCs) in indoor air is still missing. This study evaluates the use of Carbograph 5TD as an adsorbent for 60 compounds (47 VVOCs + 13 VOCs) by comparing their recoveries with different spiking modes. The influence of the spiking of the tubes in dry nitrogen, humidified air or along the whole flushing duration mimicking real sampling was investigated. 49 substances (36 VVOCs from C1 to C6) had recoveries over 70% on the adsorbent in humidified air and were validated. The linearity of the calibration curves was verified for every spiking mode and the limits of detection (LOD) and quantification (LOQ) were determined. The LOQs were lower than the existing indoor air guideline values. The robustness of the method was considered by studying the influence of the sampling volume, the sampling flow rate, the humidity level and the storage of the tubes. In general, the most volatile or polar substances were the less robust ones. The combined measurement uncertainty was calculated and lies below 35% for a vast majority of the substances. An example of an emission chamber test using polyurethane foam is shown: Carbograph 5TD performs much better than Tenax® TA for VVOCs and emissions from n-butane were quantified with combined measurement uncertainty. KW - VVOC KW - Gas chromatography KW - Thermal desorption KW - Air sampling PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581113 DO - https://doi.org/10.1039/D3AY00677H VL - 15 IS - 31 SP - 3810 EP - 3821 AN - OPUS4-58111 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chaudhuri, Somsubhro A1 - Stamm, Michael A1 - Krankenhagen, Rainer T1 - Weather-dependent passive thermography and thermal simulation of in-service wind turbine blades N2 - . To cope with the increase in the manufacturing and operation of wind turbines, wind farm operators need inspection tools that are able to provide reliable information while keeping the downtime low. Current inspection techniques require to stop the wind turbine. This work presents the current progress in the project EvalTherm, in which passive thermography is evaluated as a possible non-destructive inspection tool for operational wind turbine blades (WTBs). A methodology to obtain thermal images of rotating WTBs has been established in this project. However, the quality of the results is heavily dependent on various aspects such as weather conditions, information on the inspected WTB, damage history, etc. In this work, a section of a used WTB is simulated using finite-element modelling (FEM) as well as experimentally tested for evaluating the accuracy of the model. Such a model will provide insight into the potential thermal response of a certain structure (with specific material properties) in given weather (boundary) conditions. The model is able to provide satisfactory predictions of the thermal response of the structure, as well as indicate what thermal contrast(s) result from artificial defects introduced in the structure. T2 - WindEurope Annual Event 2023 CY - Copenhagen, Denmark DA - 25.04.2023 KW - FEM KW - Thermografie KW - Wind turbine rotor blades KW - Windenergie Anlage Rotorblätter PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582777 DO - https://doi.org/10.1088/1742-6596/2507/1/012025 VL - 2507 SP - 1 EP - 12 PB - IOP Publishing Ltd. AN - OPUS4-58277 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Feiler, Torvid A1 - Yasuda, N. A1 - Michalchuk, Adam A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit T1 - Mechanistic Investigation of an Elastically Flexible Organic Crystal N2 - Mechanical flexibility in molecular crystals is a fascinating behavior with potential for developing advanced technologies. However, the phenomenon of mechanical bending is poorly understood. We explore for the first time the atomistic origin of elastic bending in a single component organic crystal using a combination of μ-focus synchrotron X-ray diffraction and ab initio simulation. KW - Flexible crystals KW - DFT calculation KW - Bending mechanism PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581949 DO - https://doi.org/10.1021/acs.cgd.3c00473 SN - 1528-7483 VL - 23 IS - 9 SP - 6244 EP - 6249 PB - ACS Publications AN - OPUS4-58194 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinekamp, Christian A1 - Guilherme Buzanich, Ana A1 - Ahrens, M. A1 - Braun, T. A1 - Emmerling, Franziska T1 - An amorphous Lewis-acidic zirconium chlorofluoride as HF shuttle: C–F bond activation and formation N2 - An exceptional HF transfer reaction by C–F bond activation of fluoropentane and a subsequent hydrofluorination of alkynes at room temperature is reported. An amorphous Lewis-acidic Zr chlorofluoride serves as heterogeneous catalyst, which is characterised by an eightfold coordination environment at Zr including chlorine atoms. The studies are seminal in establishing sustainable fluorine chemistry. KW - ZCF KW - Heterogeneous catalysis KW - C-F bond activation KW - HF-shuttle PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582249 DO - https://doi.org/10.1039/D3CC03164K SN - 1359-7345 VL - 59 IS - 75 SP - 11224 EP - 11227 PB - RSC CY - Cambridge AN - OPUS4-58224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Morichi, M. A1 - Fanchini, E. A1 - Bruggemann, C. A1 - Perot, B. A1 - Ricard, D. A1 - Niederleithinger, Ernst T1 - Developments and experiences of the CHANCE, MICADO and PREDIS projects in radioactive waste characterization N2 - Characterization is a very important step in dealing with materials and waste streams generated during the operational and decommissioning phases of nuclear installations, including nuclear power plants. Characterization allows differentiation between materials that can be released from regulatory control and those that require further treatment and conditioning to become a stable waste form suitable for future storage and final disposal according to its waste classification. Characterization is also needed in the pre-disposal stages of radioactive waste management to demonstrate compliance with the waste acceptance criteria of the facilities that will accept the different waste forms. This work will present the strategies developed and implemented by the three projects for in-depth and accurate waste characterization and investigation of the different radioactive waste packages considered. CHANCE, MICADO, and PREDIS will present their goals, the methods developed, the technologies used and the (preliminary) results contributing to the improvement of the safety and the data and information quality of the waste packages analyzed at the different stages of the waste management process. Special emphasis will also be given to complementary approaches highlighting the usability of the technologies, the accessibility of the data, and the problem-solving of the three projects within the European panorama. KW - Waste management KW - Radioactive waste KW - Waste chracterization PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571872 DO - https://doi.org/10.1051/epjn/2022052 SN - 2491-9292 VL - 9 IS - 12 SP - 1 EP - 11 PB - EPJ Nuclear Sci. Technol. AN - OPUS4-57187 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mazumdar, Tilomatta A1 - Bartholomäus, A. A1 - McMahon, Dino Peter ED - Rokas, A. T1 - Draft Genome of the Entomopathogenic Fungus Metarhizium robertsii DSM 1490 N2 - Metarhizium robertsii DSM 1490 is a generalist entomopathogenic fungus. The mechanisms of pathogenesis of such fungi in insects like termites are not completely understood. Here, we report the draft genome sequence, as sequenced on the Oxford Nanopore platform. The genome has a GC% of 47.82 and a size of 45,688,865 bp KW - Draft Genome KW - Entomopathogenic Fungus KW - Metarhizium robertsii DSM 1490 KW - Mechanisms of pathogenesis KW - Infecting a number of insects, KW - Close proximity to colonies PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573186 DO - https://doi.org/10.1128/mra.01267-22 SN - 2576-098X VL - 2023 SP - 1 EP - 2 PB - ASM Journals CY - Nashville, USA AN - OPUS4-57318 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Terborg, R. A1 - Kim, K. J. A1 - Hodoroaba, Vasile-Dan T1 - Elemental composition and thickness determination of thin films by electron probe microanalysis N2 - Electron probe microanalysis (EPMA) applies to solid samples of homogenous (bulk) chemical composition and can usually not be applied to structures which are inhomogeneous in the micrometer range such as thin film systems down to a few nm. However, in combination with the established thin film software Stratagem, the thickness as well as the elemental composition of thin films on a substrate can be determined. This has been recently successfully demonstrated for Fe-Ni on Si and Si-Ge on Al2O3 thin film systems. For both systems five samples of different elemental composition and a reference were produced and characterised by inductively coupled plasma mass spectrometry (ICP-MS), Rutherford backscattering (RBS), and transmission electron microscopy (TEM) as reference values. Last year, a new and open-source thin film evaluation programme called BadgerFilm has been released. It can also be used to determine thin film composition and thickness from intensity ratios of the unknown sample and standards (k-ratios). In this contribution, we reevaluated the data acquired for the Fe-Ni and Si-Ge systems using the BadgerFilm software package and compared the obtained elemental compositions and thickness values with the results of the Stratagem software and the reference methods. The conclusion is that the BadgerFilm software shows good agreement with the elemental composition and thickness calculated by Stratagem (mostly <2% for both composition and thickness) and with the reference values for two representative thin film systems (<1%–2% for composition and <10%–20% for thickness). KW - Elemental composition KW - EPMA KW - Film thickness KW - Thin films PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576368 DO - https://doi.org/10.1002/sia.7183 SN - 0142-2421 VL - 55 SP - 496 EP - 500 PB - Wiley AN - OPUS4-57636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, W. A1 - Schweins, R. A1 - Nöcker, B. A1 - Kohlbrecher, J. A1 - Smales, Glen Jacob A1 - Huber, K. T1 - Comparative study of the co-assembly behaviour of 3-chloro-4-hydroxy-phenylazo dyes with DTAB N2 - The co-assembly of three one-fold negatively charged 3-chloro-4-hydroxy-phenylazo dyes (Yellow, Blue and Red) with the cationic surfactant dodecyltrimethylammoniumbromide (DTAB) was studied to probe dye–DTAB binding stoichiometry and assembly morphology. For each dye, phase separation was observed above a given dye : DTAB ratio with the ratio depending on the dye. While Yellow and DTAB showed liquid/liquid phase separation above Yellow : DTAB = 1 : 1.67, crystalline dye–DTAB complexes were observed for Blue–DTAB and Red–DTAB above Blue : DTAB = 1 : 2.56 and Red : DTAB = 1 : 2.94 respecively. In homogeneous solution, UV/vis spectroscopic investigations suggest stochiometries of Yellow : DTAB = 1 : 2, Blue : DTAB = 1 : 3 and Red : DTAB = 1 : 4. It was concluded, that Yellow exhibits the highest dye : DTAB binding stoichiometry in both, dye–surfactant complexes in the 2-phase region and in solution, whereas the lowest dye : DTAB binding stoichiometry was observed for Red–DTAB in both cases. The observed stoichiometries are inversely correlated to the impact dye addition has on the morphology of DTAB micelles. Generally, addition of dye to DTAB micelles leads to a reduction in spontaneous curvature of these micelles and to the formation of triaxial ellipsoidal or cylindrical micelles from oblate ellipsoidal DTAB micelles. At a DTAB concentration of 30 mM and a dye concentration of 5 mM, this effect was most pronounced for Red and least pronounced for Yellow, whilst Blue showed an intermediate effect. KW - Dye KW - DTAB KW - SAXS KW - Small-angle X-ray scattering KW - X-ray scattering KW - Data analysis KW - Micelle PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576978 DO - https://doi.org/10.1039/D3SM00501A SN - 1744-683X VL - 19 IS - 24 SP - 4588 EP - 4598 PB - Royal Society of Chemistry AN - OPUS4-57697 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lengas, Nikolaos A1 - Müller, Karsten A1 - Schlick-Hasper, Eva A1 - Neitsch, Marcel A1 - Johann, Sergej A1 - Zehn, M. W. T1 - Improved criteria for evaluating impact targets in regulative drop tests of dangerous goods packagings N2 - For dangerous goods packagings, drop testing onto an essential unyielding target can be used to assess the mechanical resistance to impact loads. Adopted regulations like ADR/RID require that the impact surface provided shall be integral with a mass at least 50 times than that of the heaviest package to be tested. The problem is that many manufacturers do not possess impact targets that satisfy the required 50 times mass ratio for regulative drop tests during series production. The objective of this work is to verify existing and define improved criteria for impact target structures based on systematic investigations. Previous evidence highlights the relevance of other parameters in addition to the mass ratio. Therefore, in this research, a variation of drop test parameters was carried out experimentally. Furthermore, numerical vibration analysis was applied to investigate the deformability of the impact surface. The results conclude that the mass ratio of 1:50 cannot be defined as a decisive criterion. In order to determine the influence of further drop test parameters, the research findings were used to validate a parametric model which assesses impact target deflection. An approximation quality of over 90 % was achieved. As a result, new evaluation criteria are proposed. Firstly, a method for identifying critical impact target designs is provided. Secondly, a new comprehensive formula compares the approximated maximum deflection of a real impact target to the respective theoretical threshold derived from a worst-case assumption. In practice, this leads to great advantages in the evaluation of already installed impact targets for dangerous goods packagings. KW - Corrugated fibreboard box KW - Dangerous goods packagings KW - Drop test KW - Impact target KW - Mechanical response KW - Steel drum KW - Structural dynamics PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576985 DO - https://doi.org/10.1002/pts.2759 SN - 0894-3214 SP - 1 EP - 14 PB - John Wiley & Sons Ltd AN - OPUS4-57698 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Obaton, A.-F. A1 - Fain, J. A1 - Meinel, Dietmar A1 - Tsamos, Athanasios A1 - Léonard, F. A1 - Lécuelle, B. A1 - Djemaï, M. T1 - In Vivo Bone Progression in and around Lattice Implants Additively Manufactured with a New Titanium Alloy N2 - The osseointegration in/around additively manufactured (AM) lattice structures of a new titanium alloy, Ti–19Nb–14Zr, was evaluated. Different lattices with increasingly high sidewalls gradually closing them were manufactured and implanted in sheep. After removal, the bone–interface implant (BII) and bone–implant contact (BIC) were studied from 3D X-ray computed tomography images. Measured BII of less than 10 µm and BIC of 95% are evidence of excellent osseointegration. Since AMnaturally leads to a high-roughness surface finish, the wettability of the implant is increased. The new alloy possesses an increased affinity to the bone. The lattice provides crevices in which the biological tissue can jump in and cling. The combination of these factors is pushing ossification beyond its natural limits. Therefore, the quality and speed of the ossification and osseointegration in/around these Ti–19Nb–14Zr laterally closed lattice implants open the possibility of bone spline key of prostheses. This enables the stabilization of the implant into the bone while keeping the possibility of punctual hooks allowing the implant to be removed more easily if required. Thus, this new titanium alloy and such laterally closed lattice structures are appropriate candidates to be implemented in a new generation of implants. KW - Osseointegration KW - X-ray computed tomography KW - Additive manufacturing KW - Machine learning segmentation PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-577066 DO - https://doi.org/10.3390/app13127282 VL - 13 IS - 12 SP - 1 EP - 18 PB - MDPI CY - Basel, Switzerland AN - OPUS4-57706 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nguyen, H. G. A1 - Toman, B. A1 - van Zee, R. A1 - Prinz, Carsten A1 - Thommes, M. A1 - Ahmad, R. A1 - Kiska, D. A1 - Salinger, J. A1 - Walton, I. A1 - Walton, K. A1 - Broom, D. A1 - Benham, M. A1 - Ansari, H. A1 - Pini, R. A1 - Petit, C. A1 - Adolphs, J. A1 - Schreiber, A. A1 - Shigeoka, T. A1 - Konishi, Y. A1 - Nakai, K. A1 - Henninger, M. A1 - Petrzik, T. A1 - Kececi, C. A1 - Martis, V. A1 - Paschke, T. A1 - Mangano, E. A1 - Brandani, S. T1 - Reference isotherms for water vapor sorption on nanoporous carbon: results of an interlaboratory study N2 - This paper reports the results of an international interlaboratory study sponsored by the Versailles Project on Advanced Materials and Standards (VAMAS) and led by the National Institute of Standards and Technology (NIST) on the measurement of water vapor sorption isotherms at 25 °C on a pelletized nanoporous carbon (BAM-P109, a certified reference material). Thirteen laboratories participated in the study and contributed nine pure water vapor isotherms and four relative humidity isotherms, using nitrogen as the carrier gas. From these data, reference isotherms, along with the 95% uncertainty interval (Uk=2), were determined and are reported in a tabular format. KW - BAM-P109 KW - Interlaboratory study KW - Nanoporous carbon KW - Reference isotherm KW - VAMAS PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576560 DO - https://doi.org/10.1007/s10450-023-00383-1 SN - 0929-5607 SP - 1 EP - 12 PB - Springer CY - Heidelberg AN - OPUS4-57656 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas A1 - Trappe, Volker A1 - Müller, Bernd R. A1 - Bruno, Giovanni T1 - Rissentwicklung in CFK-Laminaten nachgewiesen durch in situ Röntgen-Refraktion N2 - In Leichtbauanwendungen sind Materialien mit geringen Dichten und hohen Festigkeiten gefragt. Insbesondere Faser-Kunststoff-Verbunde (FKV) erfüllen diese Anforderungen und werden zunehmend für Strukturbauteile eingesetzt. Die Oberflächen moderner Rotorblätter von Windkraftanlagen werden aus FKV gefertigt. Das Versagen dieser Materialien hat massiven Einfluss auf die Einsatzfähigkeit der gesamten Windkraftanlage. Daher ist die Kenntnis des Versagensverhaltens dieser Komponenten unter statischer und zyklischer Belastung von großem Interesse, um die Betriebsbeanspruchung abzuschätzen. Im Idealfall wird die Schadensentwicklung unter Betriebslast mit zerstörungsfreien in-situ-Prüfverfahren ermittelt. Hier berichten wir über die Beobachtung der Rissentwicklung in Carbon-Faserverstärkten Kunststoffen (CFK) unter kontinuierlicher Zugbelastung durch in-situ Synchrotron-Röntgenrefraktionsradiographie. Eine selbst entwickelte elektromechanische Zugprüfmaschine mit einem Kraftbereich bis zu 15 kN wurde in den Strahlengang an der BAMline (BESSY II) integriert. Da in herkömmlichen (Absorptions-) Radiographien Defekte wie Zwischenfaserbrüche oder Faser-Matrix-Enthaftung keinen ausreichenden Kontrast verursachen, wird zur Kontrastanhebung die Röntgenrefraktion benutzt. Hier wird das sogenannte Diffraction Enhanced Imaging (DEI) angewandt, um Primär- und gebrochene Strahlung mit Hilfe eines Analysatorkristalls zu trennen. Diese Technik ermöglicht schnelle Messungen mit einem Gesichtsfeld von einigen Quadratmillimetern (hier: 14 mm × 7.2 mm) und ist ideal für in-situ Untersuchungen. Die Bildgebung und der Zugversuch erfolgen mit einer Bildfrequenz von 0.7 / s und einer Dehnrate von 0.00055 / s . Bei 0°/90° Fasergelegen treten die ersten Zwischenfaserrisse bei 380 MPa (Dehnung 0.8 %) auf. Vor dem Versagen bei ca. 760 MPa (Dehnung 2.0 %) beobachten wir die Ausbildung eines nahezu äquidistanten Rissmusters (Risse in ca. 1 mm Abstand), das sich im geschädigten Zustand über die gesamte Probe erstreckt. T2 - DACH-Jahrestagung 2023 CY - Friedrichshafen, Germany DA - 15.05.2023 KW - Röntgen-Refraktion KW - Synchrotronstrahlung KW - CFK KW - Rissentwicklung PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576230 SN - 978-3-947971-29-9 VL - BB 180 SP - 1 EP - 8 AN - OPUS4-57623 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sözen, H.I. A1 - Ener, S. A1 - Maccari, F. A1 - Fayyazi, B. A1 - Gutfleisch, O. A1 - Neugebauer, J. A1 - Hickel, Tilmann T1 - Combined ab initio and experimental screening of phase stabilities in the Ce-Fe-Ti-X system (X = 3d and 4d metals) N2 - One of the main challenges for the synthesis and application of the promising hard-magnetic compound CeFe11Ti is the formation of Laves phases that are detrimental for their thermodynamic stability and magnetic properties. In this paper, we present an ab initio based approach to modify the stability of these phases in the Ce-Fe-Ti system by additions of 3d and 4d elements. We combine highly accurate free-energy calculations with an efficient screening technique to determine the critical annealing temperature for the formation of Ce(Fe,X)11Ti. The central findings are the dominant role of the formation enthalpy at T = 0 K on chemical trends and the major relevance of partial chemical decompositions. Based on these insights, promising transition metals to promote the stability of the hard-magnetic phase, such as Zn and Tc, were predicted. The comparison with suction casting and reactive crucible melting experiments for Ce-Fe-Ti-X (X = Cu, Ga, Co, and Cr) highlights the relevance of additional phases and quaternary elements. KW - Density functional theory KW - Phase stability KW - Energy materials PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568850 DO - https://doi.org/10.1103/PhysRevMaterials.7.014410 SN - 2475-9953 VL - 7 SP - 1 EP - 15 AN - OPUS4-56885 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heisterkamp, I. A1 - Gartiser, S. A1 - Schoknecht, Ute A1 - Happel, O. A1 - Kalbe, Ute A1 - Kretzschmar, M. A1 - Ilvonen, O. T1 - Investigating the ecotoxicity of construction product eluates as multicomponent mixtures N2 - The release of hazardous compounds from construction products can harm human health and the environment. To improve the sustainability of construction materials, the leaching of substances from construction products and their potential environmental impact should be assessed. Twenty-seven construction products from different product groups were examined with a combination of standardized leaching tests (dynamic surface leaching test and percolation test) and biotests (algae, daphnia, fish egg, luminescent bacteria, umu and Ames fluctuation tests). To identify the released substances, extensive qualitative and quantitative chemical analyses were performed, including gas chromatographic and liquid chromatographic screening techniques. Results: Many of the tested eluates caused signifcant ecotoxic efects. Particularly high ecotoxicities were observed for grouts (lowest ineffective dilution (LID) up to 16384) and cork granules (LID up to 24578). The results of ecotoxicity tests allow the prioritization of the eluates that should be subjected to detailed chemical analyses. Organic screening by different methods and ranking the identifed substances based on recorded hazard classification is a suitable approach to identify the relevant toxic substances. Conclusions: Determining the ecotoxicity of eluates from construction products records the summary effect of all leachable substances. This instrument is especially useful for construction products of complex and largely unknown composition. The ecotoxicological and the chemical–analytical approach complement each other in an ideal way to characterize the potential hazard of eluates from construction products and to identify the environmentally hazardous components in these eluates. Our results confirm that the proposed harmonized methods for testing eluate toxicity are an adequate and applicable procedure to move toward a more sustainable way of building and to reduce toxic effects of construction products in their use phase in the environment. KW - Construction products KW - Building materials KW - Ecotoxicity KW - Biotests KW - Leaching KW - Eluates KW - Chemical analysis KW - Analytical screening techniques KW - Mixture toxicity PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568864 DO - https://doi.org/10.1186/s12302-023-00711-w VL - 35 IS - 1 SP - 1 EP - 20 PB - Springer AN - OPUS4-56886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, J. A1 - Gong, M. A1 - Zhang, W. A1 - Mehmood, Asad A1 - Zhang, J. A1 - Ali, G. A1 - Kucernak, A. T1 - Simultaneously incorporating atomically dispersed Co-Nₓ sites with graphitic carbon layer-wrapped Co₉S₈ nanoparticles for oxygen reduction in acidic electrolyte N2 - A facile yet robust synthesis is reported herein to simultaneously incorporate atomically dispersed Co-Nₓ sites with graphitic layer-protected Co₉S₈ nanoparticles (denoted as Co SACs+Co₉S₈) as an efficient electrocatalyst for oxygen reduction in acidic solution. The Co SACs+Co₉S₈ catalyst shows low H₂O₂ selectivity (∼5 %) with high half-wave potential (E1/2) of ∼0.78 V(RHE) in 0.5 M H₂SO₄. The atomic sites of the catalyst were quantified by a nitrite stripping method and the corresponding site density of the catalyst is calculated to be 3.2×10¹⁸ sites g⁻¹. Besides, we also found the presence of a reasonable amount of Co₉S₈ nanoparticles is beneficial for the oxygen electrocatalysis. Finally, the catalyst was assembled into a membrane electrode assembly (MEA) for evaluating its performance under more practical conditions in proton exchange membrane fuel cell (PEMFC) system. KW - Co−N-Cs KW - Fuel cells KW - Single-atom catalysts KW - Oxygen reduction reaction KW - PGM-free catalysts PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575993 DO - https://doi.org/10.1002/celc.202300110 SN - 2196-0216 VL - 10 IS - 12 SP - 1 EP - 9 PB - Wiley-VCH CY - Weinheim AN - OPUS4-57599 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Czeskleba, Denis A1 - Nietzke, Jonathan A1 - Rhode, Michael A1 - Kannengießer, Thomas T1 - Investigation of stress relief crack susceptibility of CrMoV steels coarse grain HAZ via simulation of uniaxial stress conditions during PWHT N2 - Creep-resistant steels such as the 13CrMoV9-10, used in the construction of thick-walled pressure vessels, are most commonly submerged arc welded (SAW). These steels can develop stress relief cracks (SRC) if the mandatory post weld heat treatment (PWHT) is performed improperly. Current PWHT parameters, such as heating rate and holding time at a specific holding temperature, are based on both empirical experience and conventional free shrinking welding experiments to characterize the SRC-susceptibility of the weld. These cannot adequately depict the higher residual stresses caused by the structurally induced stiffness of the surrounding construction. This study discusses the development of a repeatable, precise, and time-efficient methodology to study the effects of different stress levels and heating rates on the SRC susceptibility of the coarse grain heat-affected zone (CGHAZ). For that purpose, samples were thermically treated to simulate a coarse grain heat-affected zone (CGHAZ) and subsequently exposed to representative levels of stress during the heating phase of a PWHT. The recorded stress and heating rate–dependent strains were mathematically analyzed via curve tracing/calculus to identify interdependent effects. This procedure facilitates the measurement of material characteristics such as carbide growth on grain boundaries at the µm-scale via an integrated value over the entire sample volume. The first and second derivatives show a slight, precipitate-dependent, increase in hardness of the sample, depending on the heating rate and applied stress. This new methodology generates an improved assessment of the SRC susceptibility of SAW microstructures of creep-resistant CrMoV steels. KW - Submerged arc welding KW - Creep-resistant steel KW - Stress relief cracking KW - Component-like test KW - Post weld heat treatment PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576007 DO - https://doi.org/10.1007/s40194-023-01539-x SN - 0043-2288 SP - 1 EP - 9 PB - Springer Nature CY - Basel (CH) AN - OPUS4-57600 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kinne, Marko A1 - Thöns, Sebastian T1 - Fatigue Reliability Based on Predicted Posterior Stress Ranges Determined from Strain Measurements of Wind Turbine Support Structures N2 - In the present paper, an approach for updating the continuous stress range distribution of a welded connection of a wind turbine support structure with predicted information from strain measurements is presented. Environmental conditions, such as wind or, in offshore fields, waves and currents, in combination with rotor excitations generate cyclic stresses affecting the reliability of welded joints of the support structure over the service life. Using strain measurements, these conditions can be monitored, and the resulting stress ranges, under consideration of measurement, mechanical and material uncertainties, can be reconstructed. These stress ranges can be used as an input for updating the prior probability density function (PDF) of the stress ranges predicted by the overall dynamics and a detailed design analysis. Applying Bayesian probability theory and decision theoretical implications, the predicted posterior probability density of the stress ranges is calculated based on the design information and uncertainties. This approach is exemplified, and it is shown how the predicted stress ranges and the design stress ranges are distributed. The prior and the predicted posterior stress ranges are used for a reliability calculation for potentially entering a pre-posterior decision analysis KW - Strain measurements of wind turbine support structures KW - Bayesian updating of stress ranges KW - Posterior fatigue reliability PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572663 DO - https://doi.org/10.3390/en16052225 VL - 16 IS - 5 SP - 1 EP - 26 PB - MDPI AN - OPUS4-57266 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völker, Tobias A1 - Gornushkin, Igor B. T1 - Investigation of a method for the correction of self-absorption by Planck function in laser induced breakdown spectroscopy N2 - The electron density and temperature of a laser-induced plasma can be determined from the width and intensity of the spectral lines, provided that the corresponding optical transitions are optically thin. However, the lines in laser induced plasma are often self-absorbed. One of the methods of correction of this effect is based on the use of the Planck function and an iterative numerical calculation of the plasma temperature. In this study, the method is further explored and its inherent errors and limitations are evaluated. For this, synthetic spectra are used that fully correspond to the assumed conditions of a homogeneous isothermal plasma at local thermodynamic equilibrium. Based on the error analysis, the advantages and disadvantages of the method are discussed in comparison with other methods of self-absorption correction. KW - LIBS KW - Self-absorption KW - Planck function PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572677 DO - https://doi.org/10.1039/D2JA00352J SN - 0267-9477 SP - 1 EP - 6 PB - Royal Society of Chemistry (RSC) AN - OPUS4-57267 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wandtke, Karsten A1 - Schröpfer, Dirk A1 - Scharf-Wildenhain, R. A1 - Hälsig, A. A1 - Kannengießer, Thomas A1 - Kromm, Arne A1 - Hensel, J. T1 - Influence of the WAAM process and design aspects on residual stresses in high-strength structural steels N2 - Wire arc additive manufacturing (WAAM) enables the efficient production of weight-optimized modern engineering structures. Further increases in efficiency can be achieved by using high-strength structural steels. Commercial welding consumables for WAAM are already available on the market. Lack of knowledge and guidelines regarding welding residual stress and component safety during production and operation leads to severely limited use for industry applications. The sensitive microstructure of high-strength steels carries a high risk of cold cracking; therefore, residual stresses play a crucial role. For this reason, the influences of the material, the WAAM process, and the design on the formation of residual stresses and the risk of cold cracking are being investigated. The material used has a yield strength of over 800 MPa. This strength is adjusted via solid solution strengthening and a martensitic phase transformation. The volume expansion associated with martensite formation has a significant influence on the residual stresses. The focus of the present investigation is on the additive welding parameters and component design on their influence on hardness and residual stresses, which are analyzed by means of X-ray diffraction (XRD). Reference specimens (hollow cuboids) are welded fully automated with a systematic variation of heat control and design. Welding parameters and AM geometry are correlated with the resulting microstructure, hardness, and residual stress state. Increased heat input leads to lower tensile residual stresses which causes unfavorable microstructure and mechanical properties. The component design affects heat dissipation conditions and the intensity of restraint during welding and has a significant influence on the residual stress. KW - DED-arc KW - Additive manufacturing KW - High-strength steel filler metal KW - Residual stress PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572698 DO - https://doi.org/10.1007/s40194-023-01503-9 SN - 1878-6669 VL - 67 IS - 4 SP - 987 EP - 996 PB - Springer CY - Berlin AN - OPUS4-57269 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pirskawetz, Stephan T1 - Richtlinie „Detektion von Spanndrahtbrüchen mit Schallemission“ N2 - Ein großer Teil unserer Brücken wurden in den 1950er bis 1970er Jahren als Spannbetonbrücken gebaut. Mit der damals noch relativ jungen Technologie entstanden elegante, teilweise gewagte Bauwerke mit großen Spannweiten, welche die Vorteile der Materialien Stahl und Beton geschickt kombinieren. Die Standsicherheit einiger dieser Brücken ist heute gefährdet. Die Ursachen liegen in der enorm gewachsenen Belastung durch Schwerverkehr, teilweise ungenügender Wartung und in konstruktiven und Materialschwächen, die der mangelnden Erfahrung mit der Technologie in der Bauzeit geschuldet sind. Ein neuralgischer Punkt der Bauwerke sind die in den Beton integrierten Spannglieder. Infolge von Korrosion und Ermüdung können Elemente der Spannglieder reißen, wodurch die für das Tragwerk notwendige Spannung und somit die Tragfähigkeit reduziert werden. Nicht bei allen Brücken kündigen sichtbare Risse im Beton oder auffällige Verformungen den Tragfähigkeitsverlust bzw. das finale Versagen rechtzeitig an. Die Schallemissionsanalyse ist die derzeit einzige Methode, das Reißen einzelner Spannstähle zuverlässig und mit wirtschaftlich vertretbarem Aufwand zu detektieren. Trotzdem es schon einige Spannbetonbauwerke gibt, die mit Schallemissionsanalyse überwacht werden, ist das Verfahren noch wenig bekannt. Außerdem fehlen technische Richtlinien, was die Ausschreibung und Vergabe von entsprechenden Aufträgen und die Bewertung der Angebote sehr erschwert. Um sowohl Baulastträger als auch Dienstleistungsanbieter in den Vergabeverfahren und im Betrieb der Monitoringsysteme zu unterstützen, hat sich eine Gruppe von Experten aus den Bereichen Bauingenieurwesen und Schallemission zum Entwurf einer Richtlinie „Detektion von Spanndrahtbrüchen mit Schallemission“ zusammengefunden. Mit diesem Beitrag wird die Richtlinie vorgestellt, deren Bearbeitung bis zur SCHALL 23 abgeschlossen sein soll. T2 - SCHALL 23 Entwicklung und Anwendung der Schallemissionsanalyse und Zustandsüberwachung mit geführten Wellen CY - Wetzlar, Germany DA - 21.03.2023 KW - Schallemission KW - Spannbeton KW - Brücke KW - Spannstahlbruch PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573904 SP - 1 EP - 4 PB - DGZfP CY - Berlin AN - OPUS4-57390 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pirskawetz, Stephan A1 - Schmidt, S. T1 - Detection of wire breaks in prestressed concrete bridges by Acoustic Emission analysis N2 - problem. One reason is the sensitivity to stress corrosion cracking of the prestressing steel. Failure of prestressing wires can result in collapse of the entire structure without premature indication by transverse bending cracks or considerable deformation. The response of a structure to significant number of prestressing wire breaks was studied on a bridge in Brandenburg, Germany. Two thirds of the prestressing wires in concentrated tendons of two girders were cut before the bridge was demolished. Acoustic Emission Analysis was used to detect the wire breaks. Thus, the number of wire breaks was correlated with results of other measurement techniques, in particular strain measurements on the girders. In preparation of the measurements, the acoustic properties of the bridge were determined and the suitability of Schmidt hammer impacts as an acoustic reference source was validated. KW - Real scale test KW - Acoustic emission monitoring KW - Structural health monitoring (SHM) KW - Prestressed concrete bridge KW - Stress corrosion cracking KW - Wire break KW - Destructive testing KW - Nondestructive testing PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573927 DO - https://doi.org/10.1016/j.dibe.2023.100151 SN - 2666-1659 VL - 14 SP - 1 EP - 10 PB - Elsevier Ltd AN - OPUS4-57392 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kuner, Maximilian A1 - Lisec, Jan A1 - Mauch, Tatjana A1 - Konetzki, J. A1 - Haase, H. A1 - Koch, Matthias T1 - Quantification of Ergot Alkaloids via Lysergic Acid Hydrazide—Development and Comparison of a Sum Parameter Screening Method N2 - Ergot alkaloids are a group of mycotoxins occurring in products derived from various grasses (e.g., rye) and have been regulated in the EU recently. The new maximum levels refer to the sum of the six most common ergot alkaloids in their two stereoisomeric forms in different food matrices. Typically, these twelve compounds are individually quantified via HPLC-MS/MS or -FLD and subsequently summed up to evaluate food safety in a time-consuming process. Since all these structures share the same ergoline backbone, we developed a novel sum parameter method (SPM) targeting all ergot alkaloids simultaneously via lysergic acid hydrazide. After extraction and clean-up, in analogy to the current European standard method EN 17425 (ESM) for ergot alkaloid quantitation, the samples were derivatized by an optimized hydrazinolysis protocol, which allowed quantitative conversion after 20 min at 100 °C. The new SPM was evaluated against another established HPLC-FLD-based method (LFGB) and the HPLC-MS/MS-based ESM using six naturally contaminated rye and wheat matrix reference materials. While the SPM provided comparable values to the ESM, LFGB showed deviating results. Determined recovery rates, limits of detection and quantification of all three employed methods confirm that the new SPM is a promising alternative to the classical approaches for ergot alkaloid screening in food. KW - Ergot alkaloids KW - Sum Parameter KW - Mycotoxins KW - Derivatization KW - Hydrazinolysis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573968 DO - https://doi.org/10.3390/molecules28093701 SN - 0015-2684 VL - 28 IS - 9 SP - 3701 PB - MDPI CY - Basel AN - OPUS4-57396 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Paul, Andrea ED - Reese, M. ED - Goldhammer, T. ED - Schmalsch, C. ED - Weber, J. ED - Bannick, C. G. T1 - Spectroscopic evidence for adsorption of natural organic matter on microplastics N2 - The interaction of microcroplastics (MP) with dissolved organic matter, especially humic substances, is of great importance in understanding the behavior of microplastics in aquatic ecosystems. Surface modification by humic substances plays an essential role in transport and interaction of MP with abiotic and biotic components. Previous studies on the interaction between MP and humic substances were largely based on a model compound, humic acid (Sigma-Aldrich). In our work, we therefore investigated the interaction of natural organic matter (NOM) sampled from a German surface water with low-density polyethylene particles (LDPE). Highpressure size exclusion chromatography (HPSEC) and UV/vis absorption and fluorescence spectroscopy were used to characterize the incubation solutions after modifications due to the presence of LDPE, and Raman spectroscopy was used to characterize the incubated microplastics. While the studies of the solutions generally showed only very small effects, Raman spectroscopic studies allowed clear evidence of the binding of humic fractions to MP. The comparison of the incubation of NOM and a lignite fulvic acid which also was tested further showed that specific signatures of the humic substances used could be detected by Raman spectroscopy. This provides an elegant opportunity to conduct broader studies on this issue in the future. KW - Humic matter KW - Raman KW - HPSEC KW - Fluorescence KW - MCR PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574519 DO - https://doi.org/10.1002/appl.202200126 SN - 2702-4288 SP - 1 EP - 30 PB - Wiley-VCH CY - Weinheim AN - OPUS4-57451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Omar, Hassan A1 - Hiid, Gundula A1 - Szymoniak, Paulina A1 - Hertwig, Andreas A1 - Schönhals, Andreas T1 - Growth kinetics of the adsorbed layer of poly(bisphenol A carbonate) and its effect on the glass transition behavior in thin films N2 - The glass transition behavior of thin films of poly(bisphenol A carbonate) (PBAC) was studied employing ellipsometry. The glass transition temperature increases with the reduction of the film thickness. This result is attributed to the formation of an adsorbed layer with a reduced mobility compared to bulk PBAC. Therefore, for the first time, the growth kinetics of the adsorbed layer of PBAC was investigated, prepared by leaching samples from a 200 nm thin film which were annealed for several times at three different temperatures. The thickness of each prepared adsorbed layer was measured by multiple scans using atomic force microscopy (AFM). Additionally, an unannealed sample was measured. Comparison of the measurements of the unannealed and the annealed samples provides proof of a pre-growth regime for all annealing temperatures which was not observed for other polymers. For the lowest annealing temperature after the pre-growth stage only a growth regime with a linear time dependence is observed. For higher annealing temperatures the growth kinetics changes from a linear to a logarithmic growth regime at a critical time. At the longest annealing times the films showed signs of dewetting where segments of the adsorbed film were removed from the substrate (dewetting by desorption). The dependence of the surface roughness of the PBAC surface on annealing time also confirmed that the films annealed at highest temperatures for the longest times desorbed from the substrate. KW - Ultra thin polymer films PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574531 DO - https://doi.org/10.1039/D3RA02020G SN - 2046-2069 VL - 13 IS - 21 SP - 14473 EP - 14483 PB - RSC Publishing CY - London AN - OPUS4-57453 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ermilova, Elena A1 - Weise, Matthias A1 - Hertwig, Andreas T1 - Application of imaging ellipsometry and white light interference microscopy for detection of defects in epitaxially grown 4H-SiC layers N2 - Critical defects, also known as device killers, in wide bandgap semiconductors significantly affect the performance of power electronic devices. We used the methods imaging ellipsometry (IE) and white light interference microscopy (WLIM) in a hybrid optical metrology study for fast and non-destructive detection, classification, and characterisation of defects in 4H–SiC homoepitaxial layers on 4H–SiC substrates. Ellipsometry measurement results are confirmed by WLIM. They can be successfully applied for wafer characterisation already during production of SiC epilayers and for subsequent industrial quality control. T2 - EOS Annual Meeting (EOSAM 2022) CY - Porto DA - 12.09.2022 KW - Imaging ellipsometry KW - White light interference microscopy KW - 4H–SiC KW - Defects PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-574209 DO - https://doi.org/10.1051/jeos/2023018 SN - 1990-2573 VL - 19 IS - 1 SP - 1 EP - 8 PB - EDP Sciences AN - OPUS4-57420 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baglo, K. A1 - Sauermoser, M. A1 - Lid, M. A1 - Paschke, T. A1 - Bin Afif, A. A1 - Lunzer, M. A1 - Bock, Robert A1 - Steinert, M. A1 - Flaten, A. A1 - Torgersen, J. T1 - Overcoming the transport limitations of photopolymer-derived architected carbon N2 - Photopolymer derived carbon grows in popularity, yet the range in available feature sizes is limited. Here we focus on expanding the field to low surface to volume ratio (SVR) structures. We describe a high temperature acrylic photopolymerizable precursor with FTIR and DSC and develop a thermal inert-gas treatment for producing architected carbon in the mm scale with SVR of 1.38 x10-3 μm-1. Based on TGA and MS, we distinguish two thermal regimes with activation energies of ~79 and 169 kJ mol-1, which we reason with mechanisms during the polymer’s morphologic conversion between 300 - 500 °C. The temperature range of the major dimensional shrinkage (300-440 °C, 50%) does not match the range of the largest alteration in elemental composition (440-600 °C, O/C 0.25-0.087%). The insights lead to an optimized thermal treatment with an initial ramp (2 °C min-1 to 350 °C), isothermal hold (14h), post hold ramp (0.5 °C min-1 to 440 °C) and final ramp (10 °C min-1 to 1000 °C). The resulting carbon structures are dimensionally stable, non-porous at the μm scale, and comprise an unprecedented variation in feature sizes (from mm to μm scale). The findings shall advance architected carbon to industrially relevant scales. KW - Carbon KW - Photopolymer KW - Transport limitations KW - Porous materials KW - Additive manufacturing PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575038 DO - https://doi.org/10.1002/admt.202300092 SN - 2365-709X SP - 2300092 PB - Wiley-VCH GmbH AN - OPUS4-57503 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, Cui A1 - Ebel, Kenny A1 - Heinze, Katja A1 - Resch-Genger, Ute A1 - Bald, Ilko T1 - Quantum Yield of DNA Strand Breaks under Photoexcitation of a Molecular Ruby N2 - Photodynamic therapy (PDT) used for treating cancer relies on the generation of highly reactive oxygen species, for example, singlet oxygen 1O2, by light-induced excitation of a photosensitizer (PS) in the presence of molecular oxygen, inducing DNA damage in close proximity of the PS. Although many precious metal complexes have been explored as PS for PDT and received clinical approval, only recently, the potential of photoactive complexes of nonnoble metals as PS has been discovered. Using the DNA origami technology that can absolutely quantify DNA strand break cross sections, we assessed the potential of the luminescent transition metal complex [Cr(ddpd)2]3+ (ddpd=N,N’-dimethyl-N,N’-dipyridine-2-ylpyridine-2,6-diamine) to damage DNA in an air-saturated aqueous environment upon UV/Vis illumination. The quantum yield for strand breakage, that is, the ratio of DNA strand breaks to the number of absorbed photons, was determined to 1–4%, indicating efficient transformation of photons into DNA strand breaks by [Cr(ddpd)2]3+. KW - Fluorescence KW - Synthesis KW - Production KW - Optical spectroscopy KW - Ligand KW - Photophysics KW - Cr(III) KW - Mechanism KW - NIR KW - PDT KW - Singlet oxygen KW - DNA KW - Origami KW - Quantum yield PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573631 DO - https://doi.org/10.1002/chem.202203719 SP - 1 EP - 7 AN - OPUS4-57363 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Würth, Christian A1 - Behnke, Thomas A1 - Gienger, J. A1 - Resch-Genger, Ute T1 - Efficiency scale for scatteringluminescent particles linkedto fundamental and measurablespectroscopic properties N2 - Comparing the performance of molecular and nanoscale luminophores and luminescent microand nanoparticles and estimating achievable signal amplitudes and limits of detection requires a standardizable intensity scale. This initiated the development of the relative MESF (number of molecules of equivalent soluble fluorochromes) and ERF (equivalent reference fluorophores) scales for flow cytometry and fluorescence microscopy. Both intensity scales rely on fluorescence intensity values assigned to fluorescent calibration beads by an intensity comparison to spectrally closely matching fluorophore solutions of known concentration using a spectrofluorometer. Alternatively, the luminophore or bead brightness (B) can be determined that equals the product of the absorption cross section (σa) at the excitation wavelength (σa(λex)) and the photoluminescence quantum yield (Φpl). Thereby, an absolute scale based on fundamental and measurable spectroscopic properties can be realized which is independent of particle size, material, and luminophore staining or labeling density and considers the sensitivity of the optical properties of luminophores to their environment. Aiming for establishing such a brightness scale for light-scattering dispersions of luminescent particles with sizes exceeding a few ten nanometers, we demonstrate how the brightness of quasi-monodisperse 25 nm, 100 nm, and 1 μm sized polystyrene particles (PSP), loaded with two different dyes in varying concentrations, can be obtained with a single custom-designed integrating sphere setup that enables the absolute determination of Φpl and transmittance and diffuse reflectance measurements. The resulting Φpl, σa(λex), imaginary parts of the refractive index, and calculated B values of these samples are given in dependence of the number of incorporated dye molecule per particle. Finally, a unitless luminescence efficiency (LE) is defined allowing for the direct comparison of luminescence efficiencies of particles with different sizes. KW - Brightness KW - Quantum yield KW - Cross section KW - Lluminescence PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573680 DO - https://doi.org/10.1038/s41598-023-32933-6 VL - 13 IS - 1 SP - 14 PB - Nature AN - OPUS4-57368 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Matamoros-Veloza, A. A1 - Stawski, Tomasz A1 - Vargas, S. A1 - Neville, A. T1 - Study of a Local Structure at the Interface between Corrosion Films and Carbon Steel Surface in Undersaturated CO2 Environments N2 - Industries transporting CO2 gas-saturated fluids have infrastructures made of carbon steel. This is a good material with great mechanical properties but prone to corrosion and potential failure. Corrosion in sweet environments involves the formation of FeCO3 as a corrosion film, which is recognized to play a protective role under certain conditions. This work on the dissolution of corrosion films in sweet environments, under acidic and undersaturated conditions, demonstrates that the effects on the integrity of steel are far more significant than the damage observed on the surface of the corrosion film. Our results prove that dissolution of FeCO3 involved the presence of an amorphous phase, the intermediate formation of FeCl2 or FeCl+, and the presence of a phase with short distance atom–atom correlations. The amorphous phase was identified as a mixture of retained γ-Fe and Fe3C. Partially broken α-Fe and Fe3C structures were identified to prove the damage on the material, confirming the interface zone without evident damage on the corrosion film. Dissolution affected both the α-Fe and FeCO3, with the lattice [102̅] from the FeCO3 crystalline structure being the fastest to dissolve. The damage of steel at the molecular scale was evident at the macroscale with pit depths of up to 250 μm. The impact on the integrity of steel can be, therefore, more drastic than frequently reported in industrial operations of CO2 transport industries that use cleaning procedures (e.g., acid treatment, pigging) as part of their operational activities. KW - Steel KW - Corrosion KW - Siderite KW - Diffraction KW - Pair distribution function KW - Synchrotron PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572156 DO - https://doi.org/10.1021/acsomega.2c07631 SN - 2470-1343 VL - 8 IS - 9 SP - 8497 EP - 8504 PB - ACS AN - OPUS4-57215 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mundra, S. A1 - Samson, G. A1 - Masi, G. A1 - Achenbach, R. A1 - Bastidas, D. M. A1 - Bernal, S. A. A1 - Bignozzi, M. C. A1 - Criado, M. A1 - Cyr, M. A1 - Gartner, N. A1 - von Greve-Dierfeld, S. A1 - Legat, A. A1 - Nikoonasab, Ali A1 - Provis, J. L. A1 - Raupach, M. A1 - Gluth, Gregor T1 - Application of electrochemical methods for studying steel corrosion in alkali-activated materials N2 - Alkali-activated materials (AAMs) are binders that can complement and partially substitute the current use of conventional cement. However, the present knowledge about how AAMs protect steel reinforcement in concrete elements is incomplete, and uncertainties exist regarding the application of electrochemical methods to investigate this issue. The present review by EFC WP11-Task Force ‘Corrosion of steel in alkali-activated materials’ demonstrates that important differences exist between AAMs and Portland cement, and between different classes of AAMs, which are mainly caused by differing pore solution compositions, and which affect the outcomes of electrochemical measurements. The high sulfide concentrations in blast furnace slag-based AAMs lead to distinct anodic polarisation curves, unusually low open circuit potentials, and low polarisation resistances, which might be incorrectly interpreted as indicating active corrosion of steel reinforcement. No systematic study of the influence of the steel–concrete interface on the susceptibility of steel to corrosion in AAMs is available. Less common electrochemical methods present an opportunity for future progress in the field. KW - Alkali-activated materials KW - Reinforcement corrosion KW - Steel corrrosion KW - Electrochemical methods KW - Concrete PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572241 DO - https://doi.org/10.1002/maco.202313743 SN - 1521-4176 VL - 74 IS - 7 SP - 988 EP - 1008 PB - Wiley-VCH CY - Weinheim AN - OPUS4-57224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Barzegar, M. A1 - Pasadas, D. J. A1 - Ribeiro, A. L. A1 - Ramos, H. G. A1 - Lugovtsova, Yevgeniya A1 - Bulling, Jannis T1 - Polar Coordinate for Damage Imaging of Adhesively Bonded Plates Using Ultrasonic Guided Waves and Laser Doppler Vibrometer Measurements N2 - Wavefield measurements by a scanning laser Doppler vibrometer are generally carried out in a cartesian coordinate. As a piezoelectric transducer generates Lamb waves following radial paths, the use of a polar coordinate can be a suitable alternative to the use of a cartesian coordinate. Therefore, in the proposed method, using a single transducer placed on the center of the specimen, the measured wavefields are transformed into polar coordinates, making several identical radial line inspections from the center in a direction of incident waves. Taking advantage of the properties of the polar coordinates, a signal processing technique is proposed through a frequency-wavenumber filtering process in these coordinates. In this technique, by using proper filters, unwanted wave modes of the incident wave along with all reflected waves are filtered out. In addition, the conventional features of RMS and Euclidean distance are adapted for the polar coordinate system to image the bonded plate. The proposed signal processing and damage imaging are first introduced through a numerical simulation. Then, the performance of the proposed technique is presented by experimental measurements of two specimens including adhesively bonded carbon fiber-reinforced plastic composite plates and bonded aluminum plates. KW - Lamb waves KW - Composites KW - Disbond PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573386 DO - https://doi.org/10.1109/TIM.2023.3267528 SN - 0018-9456 VL - 72 SP - 1 EP - 11 PB - IEEE CY - Piscataway Township, New Jersey, USA AN - OPUS4-57338 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Feltin, N. A1 - Crouzier, L. A1 - Delvallée, A. A1 - Pellegrino, F A1 - Maurino, V. A1 - Bartczak, D. A1 - Goenaga-Infante, H. A1 - Taché, O. A1 - Marguet, S. A1 - Testard, F. A1 - Artous, S. A1 - Saint-Antonin, F. A1 - Salzmann, Christoph A1 - Deumer, J. A1 - Gollwitzer, C. A1 - Koops, R. A1 - Sebaïhi, N. A1 - Fontanges, R. A1 - Neuwirth, M. A1 - Bergmann, D. A1 - Hüser, D. A1 - Klein, T. A1 - Hodoroaba, Vasile-Dan T1 - Metrological Protocols for Reaching Reliable and SI-Traceable Size Results for Multi-Modal and Complexly Shaped Reference Nanoparticles N2 - The study described in this paper was conducted in the framework of the European nPSize project (EMPIR program) with the main objective of proposing new reference certified nanomaterials for the market in order to improve the reliability and traceability of nanoparticle size measurements. For this purpose, bimodal populations as well as complexly shaped nanoparticles (bipyramids, cubes, and rods) were synthesized. An inter-laboratory comparison was organized for comparing the size measurements of the selected nanoparticle samples performed with electron microscopy (TEM, SEM, and TSEM), scanning probe microscopy (AFM), or small-angle X-ray scattering (SAXS). The results demonstrate good consistency of the measured size by the different techniques in cases where special care was taken for sample preparation, instrument calibration, and the clear definition of the measurand. For each characterization method, the calibration process is described and a semi-quantitative table grouping the main error sources is proposed for estimating the uncertainties associated with the measurements. Regarding microscopy-based techniques applied to complexly shaped nanoparticles, data dispersion can be observed when the size measurements are affected by the orientation of the nanoparticles on the substrate. For the most complex materials, hybrid approaches combining several complementary techniques were tested, with the outcome being that the reliability of the size results was improved. KW - Certified reference nanomaterials KW - Traceable nanoparticle size measurements; KW - Hybrid metrology KW - Scanning probe microscopy KW - Small-angle X-ray scattering KW - Electron microscopy PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571902 DO - https://doi.org/10.3390/nano13060993 SN - 2079-4991 VL - 13 IS - 6 - Special Issue "Identification and Quantification of Nanomaterials" SP - 1 EP - 25 PB - MDPI CY - Basel, CH AN - OPUS4-57190 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - De la Hoz Alford, L. A1 - Pecanha de Souza, C. G. A1 - Paciornik, S. A1 - d` Almeida, J. R. M. A1 - Santos Leite, B. A1 - Avila, H. C. A1 - Léonard, F. A1 - Bruno, Giovanni T1 - Three-Dimensional Characterization of Polyurethane Foams Based on Biopolyols N2 - Two biopolyol-based foams derived from banana leaves (BL) or stems (BS) were produced, and their compression mechanical behavior and 3D microstructure were characterized. Traditional compression and in situ tests were performed during 3D image acquisition using X-ray microtomography. A methodology of image acquisition, processing, and analysis was developed to discriminate the foam cells and measure their numbers, volumes, and shapes along with the compression steps. The two foams had similar compression behaviors, but the average cell volume was five times larger for the BS foam than the BL foam. It was also shown that the number of cells increased with increasing compression while the average cell volume decreased. Cell shapes were elongated and did not change with compression. A possible explanation for these characteristics was proposed based on the possibility of cell collapse. The developed methodology will facilitate a broader study of biopolyol-based foams intending to verify the possibility of using these foams as green alternatives to the typical petrol-based foams. KW - Compression mechanical KW - Biopolyol KW - Banana KW - 3D microstructure KW - X-ray microtomography PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571982 DO - https://doi.org/10.3390/ma16052118 SN - 1996-1944 VL - 16 IS - 5 SP - 1 EP - 12 PB - MDPI CY - Basel AN - OPUS4-57198 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Markötter, Henning A1 - Müller, Bernd R. A1 - Kupsch, Andreas A1 - Evsevleev, Sergei A1 - Arlt, T. A1 - Ulbricht, Alexander A1 - Dayani, Shahabeddin A1 - Bruno, Giovanni T1 - A Review of X-Ray Imaging at the BAMline (BESSY II) N2 - The hard X-ray beamline BAMline at BESSY II (Berlin, Germany) has now been in service for 20 years. Several improvements have been implemented in this time, and this review provides an overview of the imaging methods available at the BAMline. Besides classic full-field synchrotron X-ray computed tomography (SXCT), also absorption edge CT, synchrotron X-ray refraction radiography (SXRR), and synchrotron X-ray refraction tomography (SXRCT) are used for imaging. Moreover, virtually any of those techniques are currently coupled in situ or operando with ancillary equipment such as load rigs, furnaces, or potentiostats. Each of the available techniques is explained and both the current and the potential usage are described with corresponding examples. The potential use is manifold, the examples cover organic materials, composite materials, energy-related materials, biological samples, and materials related to additive manufacturing. The article includes published examples as well as some unpublished applications. KW - Material science KW - Radiography KW - Refraction KW - Tomography KW - X-ray imaging PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572417 DO - https://doi.org/10.1002/adem.202201034 SN - 1438-1656 SP - 1 EP - 22 PB - Wiley VHC-Verlag AN - OPUS4-57241 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riechers, Birte A1 - Ott, C. A1 - Das, S. M. A1 - Liebscher, C. A1 - Samwer, K. A1 - Derlet, P. M. A1 - Maaß, Robert T1 - On the elastic microstructure of bulk metallic glasses N2 - Metallic glasses (MGs) are known to be structurally heterogeneous at the nanometer (nm) scale. In addition, elastic property mapping has indicated the presence of at least an order-of-magnitude larger length scales, of which the origin continues to remain unknown. Here we demonstrate the existence of an elastic decorrelation length of the order of 100 nm in a Zr-based bulk MG using spatially resolved elastic property mapping via nanoindentation. Since compositional modulations sufficiently large to account for this elastic microstructure were not resolved by analytical scanning-transmission electron microscopy, chemical phase separation such as spinodal decomposition cannot explain their occurrence as previously suggested. Instead, we argue that the revealed long-range elastic modulations stem from structural variations affecting the local density. These emerge during solidification and are strongly influenced by the cooling constraints imposed on bulk MGs during the casting process. KW - Metallic glasses KW - Nanoindentation KW - Elastic microstructure PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573504 DO - https://doi.org/10.1016/j.matdes.2023.111929 SN - 0264-1275 VL - 229 SP - 1 EP - 8 PB - Elsevier Ltd. CY - Amsterdam, Niederlande AN - OPUS4-57350 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bui, M. A1 - Hoffmann, K. F. A1 - Braun, T. A1 - Riedel, S. A1 - Heinekamp, Christian A1 - Scheurell, K. A1 - Scholz, G. A1 - Stawski, Tomasz A1 - Emmerling, Franziska T1 - An Amorphous Teflate Doped Aluminium Chlorofluoride: A Solid Lewis-Superacid for the Dehydrofluorination of Fluoroalkanes N2 - Ananion-dopedaluminiumchlorofluoride AlCl0.1F2.8(OTeF5)0.1(ACF-teflate) was synthesized.The material contains pentafluor-oorthotellurate(teflate)groups, which mimic fluoride ions electronically, but are sterically more demanding. They are embedded into the amorphous structure. The latter was studied by PDF analysis, EXAFS data and MAS NMR spectroscopy. The mesoporous powder is a Lewis superacid, and ATR-IR spectra of adsorbed CD3CN reveal a blue-shift of the adsorption band by73 cm-1, which is larger than the shift for SbF5. Remarkably,ACF-teflate catalyzes dehydrofluorination reactions of mono-fluoroalkanes to yield olefins in C6D6. In these cases,no Friedel-Crafts products were formed. KW - Aluminium fluorides KW - Aluminium teflates KW - C-F bond activation KW - Lewis superacids KW - Silanes PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572290 DO - https://doi.org/10.1002/cctc.202300350 SN - 1867-3880 SP - 1 EP - 7 PB - Wiley VHC-Verlag AN - OPUS4-57229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hurtado-Hurtado, G. A1 - Morales-Velazquez, L. A1 - Otremba, Frank A1 - Jáuregui-Correa, J. C. T1 - Railcar Dynamic Response during Braking Maneuvers Based on Frequency Analysis N2 - The dynamic response of a vehicle during braking is influenced by the tangential forces developed at the wheel-rail’s contact surface. The friction coefficient affects the load transfer from the wheel’s tread to the vehicle. In this work, the vibrations of a scale-down railway vehicle are monitored during braking and their relationship with the friction coefficient between wheel and rail is found out. The vehicle is instrumented with encoders, accelerometers, and is controlled via Bluetooth. The tests are carried out with clean and friction-modified rails. The tangential forces transmitted from the wheel to the railcar’s body are visualized in time and frequency using a proposed correlation algorithm based on the outputs of the ContinuousWavelet Transform (CWT). The results demonstrate that tangential forces have a significant impact on railway vehicles under conditions of high friction coefficients and large creep values. KW - Railway vibration measurements KW - Vibration signal analysis KW - Wheel-rail tangential forces KW - Railway braking forces KW - Wheel-rail friction coefficient PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572309 DO - https://doi.org/10.3390/app13074132 VL - 13 IS - 7 SP - 1 EP - 15 PB - MDPI AN - OPUS4-57230 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strangfeld, Christoph A1 - Stolpe, Heiko A1 - Wiehle, Philipp T1 - Moisture diffusion affected by the Knudsen effect in temporal changing pore networks N2 - Almost all building materials in civil engineering have an open porosity and interact with or are affected by the environmental conditions. Structures might suffer from effects such as moisture adsorption, carbonation, corrosion, penetration of salt ions and chemical substances, etc. In the hygroscopic range, these processes are mostly driven by diffusion. Due to the confinement of small pores (< 1 µm), the Knudsen effect reduces the molecular diffusion. This reduction can become more significant in case of temporal changing pore systems because of physisorption of water vapor, carbonation, or chemisorption. In this study, unstabilised earth blocks and earth masonry are investigated. In a first step, the pore size distribution of the blocks is measured and sorption isotherms are recorded in experiments. Besides the ordinary physisorption, the involved clay minerals undergo swelling or shrinking due to chemisorption. The following two effects must be considered: first, the reduction of the available pore space by the adsorbed water layer. For this, the Hillerborg sorption theory is used, which is a combination of the well-known Brunauer-Emmett-Teller sorption theory and the Kelvin equation. This allows the computation of adsorbed water layers even in curved pore geometries. Second, the variation of the initial pore size distribution due to chemisorption needs to be modelled. Based on these two models, the effective diffusion coefficient can be predicted. For validation, arrays of relative humidity sensors were embedded into a free-standing earth masonry wall. This monitoring was carried out over more than a year to have a broad variety of environmental conditions and was located in Berlin, Germany. The prediction of the effective diffusion coefficient can also be transferred to other processes and allows the investigation of materials having temporarily changing pore systems. Examples are the carbonation of cementitious materials, alkali silica reaction, calcium leaching of long-lasting structures, etc. This effect becomes most prominent in the meso-pore range and might alter the effective diffusion coefficient by more than 100 %. T2 - 4th International Congress on Materials & Structural Stability CY - Rabat, Morocco DA - 08.03.2023 KW - Earth masonry KW - Material moisture KW - Molecular diffusion KW - Chemisoprtion KW - Knudsen effect KW - Physisorption PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571391 SP - 1 EP - 8 PB - RILEM CY - Champs-sur-Marne AN - OPUS4-57139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Michna, A. A1 - Pomorksa, A. A1 - Özcan Sandikcioglu, Özlem T1 - Biocompatible Macroion/Growth Factor Assemblies for Medical Applications N2 - Growth factors are a class of proteins that play a role in the proliferation (the increase in the number of cells resulting from cell division) and differentiation (when a cell undergoes changes in gene expression becoming a more specific type of cell) of cells. They can have both positive (accelerating the normal healing process) and negative effects (causing cancer) on disease progression and have potential applications in gene therapy and wound healing. However, their short half-life, low stability, and susceptibility to degradation by enzymes at body temperature make them easily degradable in vivo. To improve their effectiveness and stability, growth factors require carriers for delivery that protect them from heat, pH changes, and proteolysis. These carriers should also be able to deliver the growth factors to their intended destination. This review focuses on the current scientific literature concerning the physicochemical properties (such as biocompatibility, high affinity for binding growth factors, improved bioactivity and stability of the growth factors, protection from heat, pH changes or appropriate electric charge for growth factor attachment via electrostatic interactions) of macroions, growth factors, and macroion-growth factor assemblies, as well as their potential uses in medicine (e.g., diabetic wound healing, tissue regeneration, and cancer therapy). Specific attention is given to three types of growth factors: vascular endothelial growth factors, human fibroblast growth factors, and neurotrophins, as well as selected biocompatible synthetic macroions (obtained through standard polymerization techniques) and polysaccharides (natural macroions composed of repeating monomeric units of monosaccharides). Understanding the mechanisms by which growth factors bind to potential carriers could lead to more effective delivery methods for these proteins, which are of significant interest in the diagnosis and treatment of neurodegenerative and civilization diseases, as well as in the healing of chronic wounds. KW - Polyelectrolytes KW - Polysaccharides KW - Vascular endothelial growth factor KW - Human fibroblast growth factors KW - Neurotrophins KW - Macroion/growth factor assemblies PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579820 DO - https://doi.org/10.3390/biom13040609 VL - 13 IS - 4 SP - 1 EP - 48 PB - MDPI AN - OPUS4-57982 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Karapanagiotis, Christos A1 - Krebber, Katerina T1 - Machine Learning Approaches in Brillouin Distributed Fiber Optic Sensors N2 - This paper presents reported machine learning approaches in the field of Brillouin distributed fiber optic sensors (DFOSs). The increasing popularity of Brillouin DFOSs stems from their capability to continuously monitor temperature and strain along kilometer-long optical fibers, rendering them attractive for industrial applications, such as the structural health monitoring of large civil infrastructures and pipelines. In recent years, machine learning has been integrated into the Brillouin DFOS signal processing, resulting in fast and enhanced temperature, strain, and humidity measurements without increasing the system’s cost. Machine learning has also contributed to enhanced spatial resolution in Brillouin optical time domain analysis (BOTDA) systems and shorter measurement times in Brillouin optical frequency domain analysis (BOFDA) systems. This paper provides an overview of the applied machine learning methodologies in Brillouin DFOSs, as well as future perspectives in this area. KW - Distributed fiber optic sensors KW - BOTDA KW - BOFDA KW - Machine learning KW - Strain and temperature measurements KW - Artificial neural networks PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580145 DO - https://doi.org/10.3390/s23136187 VL - 23 IS - 13 SP - 1 EP - 26 PB - MDPI AN - OPUS4-58014 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Krom, I. A1 - Heikens, D. A1 - Horn, Wolfgang A1 - Wilke, Olaf A1 - Richter, Matthias A1 - Baldan, A. T1 - Metrological generation of SI-traceable gas-phase standards and reference materials for (semi-) volatile organic compounds N2 - EN 16516 sets specifications for the determination of emissions into indoor air from construction products. Reliable, accurate and International System of Unit (SI)-traceable measurement results of the emissions are the key to consumer protection. Such measurement results can be obtained by using metrologically traceable reference materials. Gas-phase standards of volatile organic compounds (VOCs) in air can be prepared by a variety of dynamic methods according to the ISO 6145 series. However, these methods are not always applicable for semi-VOCs (SVOCs) due to their high boiling point and low vapour pressure. Therefore, a novel dynamic gas mixture generation system has been developed. With this system gas-phase standards with trace level VOCs and SVOCs in air can be prepared between 10 nmol mol−1 and 1000 nmol mol−1. The VOCs and SVOCs in this study have normal boiling points ranging from 146 °C to 343 °C. Metrologically traceable reference materials of the gas-phase standard were obtained by sampling of the VOC gas-phase standard into Tenax TA® sorbent material in SilcoNert® coated stainless steel tubes. Accurately known masses between 10 ng and 1000 ng per VOC were sampled. These reference materials were used to validate the dynamic system. Furthermore, the storage and stability periods of the VOCs in the reference materials were determined as these are crucial characteristics to obtain accurate and SI-traceable reference materials. In a round robin test (RRT), the reference materials were used with the aim of demonstrating the feasibility of providing SI-traceable standard reference values for SVOCs for interlaboratory comparison purposes. Based on the results from the validation, the storage and stability studies and the RRT, gas-phase standards and reference materials of VOCs and SVOCs with relative expanded uncertainties between 5% and 12% (k = 2) have been developed. These reference standards can be used as calibrants, reference materials or quality control materials for the analysis of VOC emissions. KW - SVOC KW - Dynamic calibration gas mixtures KW - Reference materials KW - Indoor air KW - Thermal desorption PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565978 DO - https://doi.org/10.1088/1361-6501/aca704 VL - 34 IS - 3 SP - 1 EP - 13 PB - IOP Publishing AN - OPUS4-56597 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Brandt, S. A1 - Brozowski, F. A1 - Horn, Wolfgang A1 - Müller, B. T1 - Odour testing of building products: Examinations for an on-going development of the test standard ISO 16000-28 N2 - VOC-emissions and their odours from building products and furnishings present indoors should not have an impact on personal well-being or health. Odours can be measured by applying the standard ISO 16000-28. Indoor air determination of odour emissions from building products using test chambers. One of the described procedures is the assessment of perceived intensity using a comparative scale by a group of panellists. In this paper, the perceived intensity sampling procedure and its evaluation method are investigated and shown to need improvement. New technical developments in the methodology used to increase the reproducibility of measurement results are discussed. Since odour tests are used for labelling, they have a major influence on the assessment of construction products, similar to the procedure of the German Committee for Health Evaluation of Building Products (AgBB). In the original ISO standard, the evaluation is typically performed using a sampling container separated from the emission chamber. For a better sample presentation, an adapter was developed to connect the emission test chamber to the evaluation funnel and thus enable an odour assessment which is comparable to a direct measurement. The investigations show that losses of odourous substances can be greatly reduced, which is very desirable when seeking to obtain reliable results in odour measurement. Another experimental series was carried out to reduce the measurement effort in the evaluation of perceived intensity. Application of the developed greater than or less than/equal to. query could be helpful here. The results show that the query mostly leads to the same result as the evaluation of the perceived intensity using the method according to the standard but is much easier to perform. Overall, the results can contribute to improving the acceptance of the evaluation of perceived intensity using ISO 16000-28 and to determining odours from building materials increasingly more precisely. T2 - Healthy Buildings 2023 Europe CY - Aachen, Germany DA - 11.06.2023 KW - Building material KW - Odour KW - Perceived intensity KW - VOC KW - Emission test chamber PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580070 SP - 345 EP - 352 PB - ISIAQ (International Society of Indoor Air Quality and Climate) CY - Herndon, VA, USA AN - OPUS4-58007 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiesner, Yosri A1 - Hoffmann, Thomas A1 - Range, David A1 - Altmann, Korinna T1 - Microplastics in sediments of the river Rhine—A workflow for preparation and analysis of sediment samples from aquatic river systems for monitoring purposes N2 - AbstractMicroplastics (MP) can be detected in all environmental systems. Marine and terrestrial aquatic systems, especially the transported suspended solids, have often been the focus of scientific investigations in the past. Sediments of aquatic river systems, on the other hand, were often ignored due to the time‐consuming sample preparation and analysis procedures. Spectroscopic measurement methods counting particle numbers are hardly suitable as detection methods, because there are plenty of natural particles next to a small number of MP particles. Integral methods, such as thermoanalytical methods are determining the particle mass independently of the inorganic components.In this study, a workflow for sample preparation via density separation and subsequent analysis by thermal extraction desorption‐gas chromatography/mass spectrometry is presented, which leads to representative and homogeneous samples and allows fast and robust MP mass content measurements suitable for routine analysis. Polymers were identified and quantified in all samples. Polyethylene and styrene‐butadiene rubber are the dominant polymers, besides polypropylene and polystyrene. Overall, total polymer masses between 1.18 and 337.0 µg/g could be determined. Highest MP concentrations in riverbed sediment are found in sites characterized by low flow velocities in harbors and reservoirs, while MP concentrations in sandy/gravelly bed sediments with higher flow velocities are small. KW - Microplastics KW - Density separation KW - TED-GC/MS KW - NaI PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597335 DO - https://doi.org/10.1002/appl.202200125 SP - 1 EP - 10 PB - Wiley VHC-Verlag AN - OPUS4-59733 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abusafia, A. A1 - Scheid, C. A1 - Meurer, Maren A1 - Altmann, Korinna A1 - Dittmer, U. A1 - Steinmetz, H. T1 - Microplastic sampling strategies in urban drainage systems for quantification of urban emissions based on transport pathways N2 - Tracking waterborne microplastic (MP) in urban areas is a challenging task because of the various sources and transport pathways involved. Since MP occurs in low concentrations in most wastewater and stormwater streams, large sample volumes need to be captured, prepared, and carefully analyzed. The recent research in urban areas focused mainly on MP emissions at wastewater treatment plants (WWTPs), as obvious entry points into receiving waters. However, important transport pathways under wet-weather conditions are yet not been investigated thoroughly. In addition, the lack of comprehensive and comparable sampling strategies complicated the attempts for a deeper understanding of occurrence and sources. The goal of this paper is to (i) introduce and describe sampling strategies for MP at different locations in a municipal catchment area under dry and wet-weather conditions, (ii) quantify MP emissions from the entire catchment and two other smaller ones within the bigger catchment, and (iii) compare the emissions under dry and wet-weather conditions. WWTP has a high removal rate of MP (>96%), with an estimated emission rate of 189 kg/a or 0.94 g/[population equivalents (PEQ · a)], and polyethylene (PE) as the most abundant MP. The specific dry-weather emissions at a subcatchment were ≈30 g/(PEQ · a) higher than in the influent of WWTP with 23 g/(PEQ · a). Specific wet-weather emissions from large sub-catchment with higher traffic and population densities were 1952 g/(ha · a) higher than the emissions from smaller catchment (796 g/[ha · a]) with less population and traffic. The results suggest that wet-weather transport pathways are likely responsible for 2–4 times more MP emissions into receiving waters compared to dry-weather ones due to tire abrasion entered from streets through gullies. However, more investigations of wet-weather MP need to be carried out considering additional catchment attributes and storm event characteristics. KW - Combined sewer system KW - Large volume samplers KW - Microplastic pollution KW - Separate sewer system KW - Stormwater retention tank PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568271 DO - https://doi.org/10.1002/appl.202200056 SP - 1 EP - 12 PB - Wiley-VCH CY - Weinheim AN - OPUS4-56827 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Altmann, Korinna A1 - Goedecke, Caroline A1 - Bannick, C.-G. A1 - Abusafia, A. A1 - Scheid, C. A1 - Steinmetz, H. A1 - Paul, Andrea A1 - Beleites, C. A1 - Braun, U. T1 - Identification of microplastic pathways within a typical European urban wastewater system N2 - In recent years, thermoextraction/desorption-gas chromatography/mass spectrometry (TED-GC/MS) has been developed as a rapid detection method for the determination of microplastics (MP) mass contents in numerous environmentally relevant matrices and, in particular, for the measurement of polymers in water samples without time-consuming sample preparation. The TED-GC/MS method was applied to investigate a typical European municipal wastewater system for possible MP masses. Such investigations are important in view of the recent revision of the Urban Wastewater Treatment Directive. Four different representative sampling sites were selected: greywater (domestic wastewater without toilet), combined sewer, and influent and effluent of a wastewater treatment plant (WWTP). All samples were collected by fractional filtration. Filtration was carried out over mesh sizes of 500, 100, 50, and in some cases, 5 µm. Polyethylene (PE), polypropylene (PP), and polystyrene (PS) were detected in all samples, with the PE fraction dominating in all cases. Styrene-butadiene rubber which serves as an indication of tire abrasion, was only found in the influent of the WWTP. The highest MP mass contents were found in the combined sewer, so MP can become a source of pollution during heavy rain events when the capacity limits of the effluent are reached, and the polluted effluent is released uncontrolled into the environment. Based on the studies, MP retention from the WWTP could be estimated to be approximately 96%. Few trends in polymer type or mass contents were detected within the different fractions of the samples or when comparing samples to each other. KW - Microplastics KW - Microplastic analysis KW - TED-GC/MS KW - Microplastic pathways KW - Mass contents PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568289 DO - https://doi.org/doi.org/10.1002/appl.202200078 SP - 1 EP - 10 PB - Wiley-VCH CY - Weinheim AN - OPUS4-56828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dayani, Shahabeddin A1 - Markötter, Henning A1 - Krug von Nidda, Jonas A1 - Schmidt, Anita A1 - Bruno, Giovanni T1 - Quantification of the Deep Discharge Induced Asymmetric Copper Deposition in Lithium‐Ion Cells by Operando Synchrotron X‐Ray Tomography N2 - AbstractLithium‐ion cells connected in series are prone to an electrical safety risk called overdischarge. This paper presents a comprehensive investigation of the overdischarge phenomenon in lithium‐ion cells using operando nondestructive imaging. The study focuses on understanding the behavior of copper dissolution and deposition during overdischarge, which can lead to irreversible capacity loss and internal short‐circuits. By utilizing synchrotron X‐ray computed tomography (SXCT), the concentration of dissolved and deposited copper per surface area is quantified as a function of depth of discharge, confirming previous findings. The results also highlight for the first time a nonuniform distribution pattern for copper deposition on the cathode. This research provides insights for safer battery cell design. KW - Lithium Ion Batteries KW - Deep Discharge KW - Computer Tomography KW - Copper Deposition KW - Litium Ion Cells PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-592717 DO - https://doi.org/10.1002/admt.202301246 SP - 1 EP - 7 PB - Wiley AN - OPUS4-59271 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Turski Silva Diniz, Analice A1 - Marti, J. M. A1 - Schartel, Bernhard T1 - High Heat Resistance Can Be Deceiving: Dripping Behavior of Polyamide 4.6 in Fire N2 - Polyamide 4.6 (PA46) is a high-heat-resistant polymer, but it has no dripping resistance under fire. Three commercial grades of PA46 are investigated under UL 94 vertical fire test conditions. Their performances are discussed based on the materials’ structural, thermal, and rheological properties. PA46 presents flaming drops, whereas dripping is prevented in the flame-retarded PA46. Friction-modified PA46 has increased flaming dripping. Temperature profiles of the specimens under fire and the temperature of the drops are measured by thermocouples. A UL 94 vertical test configuration consisting of two flame applications is designed to assess the quantitative dripping behavior of the set of materials by the particle finite element method (PFEM). Polymer properties (activation energy and Arrhenius coefficient of decomposition, char yield, density, effective heat of combustion, heat of decomposition, specific heat capacity, and thermal conductivity) in addition to rheological responses in high temperatures are estimated and measured as input parameters for the simulations. The dripping behavior obtained by simulated materials corresponds with the experimental results in terms of time and drop size. A consistent picture of the interplay of the different phenomena controlling dripping under fire appears to deliver a better understanding of the role of different materials’ properties KW - Dripping KW - UL 94 KW - PFEM KW - High heat resistance KW - Polyamide 4.6 KW - Flammability PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586015 DO - https://doi.org/10.1002/mame.202300091 SN - 1439-2054 SN - 1438-7492 VL - 308 IS - 10 SP - 1 EP - 11 PB - Wiley-VCH AN - OPUS4-58601 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Breese, Philipp Peter A1 - Becker, Tina A1 - Oster, Simon A1 - Metz, C. A1 - Altenburg, Simon T1 - In-situ defect detection via active laser thermographic testing for PBF-LB/M N2 - Great complexity characterizes Additive Manufacturing (AM) of metallic components via laser powder bed fusion (PBF-LB/M). Due to this, defects in the printed components (like cracks and pores) are still common. Monitoring methods are commercially used, but the relationship between process data and defect formation is not well understood yet. Furthermore, defects and deformations might develop with a temporal delay to the laser energy input. The component’s actual quality is consequently only determinable after the finished process. To overcome this drawback, thermographic in-situ testing is introduced. The defocused process laser is utilized for nondestructive testing performed layer by layer throughout the build process. The results of the defect detection via infrared cameras are shown for a research PBF-LB/M machine. This creates the basis for a shift from in-situ monitoring towards in-situ testing during the AM process. Defects are detected immediately inside the process chamber, and the actual component quality is determined. T2 - Lasers in Manufacturing (LiM) CY - Munich, Germany DA - 26.06.2023 KW - Additive manufacturing KW - Laser powder bed fusion KW - Nondestructive testing KW - Laser thermography KW - Defect detection PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-585060 SP - 1 EP - 10 PB - Wissenschaftliche Gesellschaft Lasertechnik und Photonik (WLT) CY - Hannover AN - OPUS4-58506 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lenz, J. U. A1 - Pospiech, D. A1 - Komber, H. A1 - Korwitz, A. A1 - Kobsch, O. A1 - Paven, M. A1 - Albach, R. W. A1 - Günther, Martin A1 - Schartel, Bernhard T1 - Effective halogen-free flame-retardant additives for crosslinked rigid polyisocyanurate foams: Comparison of chemical structures N2 - The impact of phosphorus-containing flame retardants (FR) on rigid polyisocyanurate (PIR) foams is studied by systematic variation of the chemical structure of the FR, including non-NCO-reactive and NCO-reactive dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide (BPPO)- and 9,10 dihydro-9-oxa-10 phosphaphenanthrene-10-oxide (DOPO)-containing compounds, among them a number of compounds not reported so far. These PIR foams are compared with PIR foams without FR and with standard FRs with respect to foam properties, thermal decomposition, and fire behavior. Although BPPO and DOPO differ by just one oxygen atom, the impact on the FR properties is very significant: when the FR is a filler or a dangling (dead) end in the PIR polymer network, DOPO is more effective than BPPO. When the FR is a subunit of a diol and it is fully incorporated in the PIR network, BPPO delivers superior results. KW - Flame retardant; KW - Dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide; BPPO KW - 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide; DOPO KW - Polyisocyanurate; PIR KW - Rigid foam KW - Cone calorimeter KW - Pudovik reaction PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567712 DO - https://doi.org/10.3390/ma16010172 SN - 1996-1944 VL - 16 IS - 1 SP - 1 EP - 22 PB - MDPI CY - Basel AN - OPUS4-56771 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Strommer, Bettina A1 - Schulze, Dietmar A1 - Schartel, Bernhard A1 - Böhning, Martin T1 - The quantification of anisotropy in graphene/natural rubber nanocomposites: Evaluation of the aspect ratio, concentration, and crosslinking N2 - In the processing of nanocomposites, high shear stresses at elevated tempera-tures orient two-dimensional nanoparticles like graphene. This orientationleads to anisotropic mechanical, thermal or barrier properties of the nanocom-posite. This anisotropy is addressed in this study by comparing graphene (few-layer graphene, FLG) with a nanoscaled carbon black (nCB) at a filler contentof 3 phr, by varying the vulcanization, and by comparing different FLG con-tents. Transmission electron microscopy gives insight into the qualitative ori-entation in the nanocomposite with FLG or nCB. The storage moduli paralleland normal to the orientation reveal the direction dependency of reinforce-ment through dynamic mechanical analysis (DMA). Dimensional swellingmeasurements show a restriction of the expansion parallel to the FLG orienta-tion, and an increased expansion normal to the orientation. The vulcanizationsystem and crosslinking determine the respective level of property values, andhigher crosslinking densities increase the anisotropy in DMA resulting invalues of up to 2.9 for the quantified anisotropy factor. With increasing FLGcontent, the anisotropy increases. A comparison of the results reveals swellingmeasurements as the most suitable method for the determination of anisot-ropy. Compared to recent literature, the presented processing induces higheranisotropy, leading to higher reinforcing effects in the direction of orientation KW - Natural rubber KW - Graphene KW - Nanocomposite KW - Mechanical properties KW - Swelling PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571522 DO - https://doi.org/10.1002/app.53753 SN - 1097-4628 VL - 140 IS - 16 SP - 1 EP - 15 PB - Wiley online library CY - Hoboken, New Jersey (USA) AN - OPUS4-57152 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Tina A1 - Breese, Philipp P A1 - Metz, Christian A1 - Altenburg, Simon T1 - In-situ monitoring for PBF-LB/M processes: Does multispectral optical tomography add value in recognizing process deviations? N2 - Laser powder bed fusion of metallic components (PBF-LB/M) is gaining acceptance in industry. However, the high costs and lengthy qualification processes required for printed components create the need for more effective in-situ monitoring and testing methods. This article proposes multispectral Optical Tomography (OT) as a new approach for monitoring the PBF-LB/M process. Compared to other methods, OT is a low-cost process monitoring method that uses long-time exposure imaging to observe the build process. However, it lacks time resolution compared to expensive thermographic sensor systems. Monochromatic OT (1C-OT) is already commercially available and observes the building process layer-wise using a single wavelength window in the NIR range. Multispectral OT (nC-OT) utilizes a similar setup but can measure multiple wavelength ranges per location simultaneously. By comparing the classical 1C-OT and nC-OT approaches, this article examines the advantages of nC-OT (two channel OT and RGB-OT) in reducing the false positive rate for process deviations and approximating maximum temperatures for a better comparison between different build processes and materials. This could ultimately reduce costs and time for part qualification. The main goal of this contribution is to assess the advantages of nC-OT compared to 1C-OT for in-situ process monitoring of PBF-LB/M. T2 - Nolamp 2023 CY - Turku, Finland DA - 22.08.2023 KW - Thermography KW - Process Monitoring KW - Additive manufacturing KW - BPF-LB/M KW - In-situ PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-592498 DO - https://doi.org/10.1088/1757-899X/1296/1/012008 VL - 1296 SP - 1 EP - 11 PB - IOP Publishing CY - Bristol, UK AN - OPUS4-59249 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fornacon-Wood, C. A1 - Stühler, M. R. A1 - Gallizioli, C. A1 - Manjunatha, B. R. A1 - Wachtendorf, Volker A1 - Schartel, Bernhard A1 - Plajer, A. J. T1 - Precise construction of weather-sensitive poly(ester-alt-thioesters) from phthalic thioanhydride and oxetane N2 - We report the selective ring opening copolymerisation (ROCOP) of oxetane and phthalic thioanhydride by a heterobimetallic Cr(III)K catalyst precisely yielding semi-crystalline alternating poly(esteralt- thioesters) which show improved degradability due to the thioester links in the polymer backbone. KW - Sulfur containing polymers KW - Durability KW - Weathering KW - Synthesis PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590762 DO - https://doi.org/10.1039/d3cc03315e SN - 1364-548X VL - 59 IS - 76 SP - 11353 EP - 11356 PB - RSC AN - OPUS4-59076 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lisec, Jan A1 - Recknagel, Sebastian A1 - Prinz, Carsten A1 - Vogel, Kristin A1 - Koch, Matthias A1 - Becker, Roland T1 - eCerto—versatile software for interlaboratory data evaluation and documentation during reference material production N2 - The statistical tool eCerto was developed for the evaluation of measurement data to assign property values and associated uncertainties of reference materials. The analysis is based on collaborative studies of expert laboratories and was implemented using the R software environment. Emphasis was put on comparability of eCerto with SoftCRM, a statistical tool based on the certification strategy of the former Community Bureau of Reference. Additionally, special attention was directed towards easy usability from data collection through processing, archiving, and reporting. While the effects of outlier removal can be flexibly explored, eCerto always retains the original data set and any manipulation such as outlier removal is (graphically and tabularly) documented adequately in the report. As a major reference materials producer, the Bundesanstalt für Materialforschung und -prüfung (BAM) developed and will maintain a tool to meet the needs of modern data processing, documentation requirements, and emerging fields of RM activity. The main features of eCerto are discussed using previously certified reference materials. KW - Reference material KW - Statistics KW - Software KW - Collaborative trial PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591851 DO - https://doi.org/10.1007/s00216-023-05099-3 SP - 1 EP - 9 PB - Springer Science and Business Media LLC AN - OPUS4-59185 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Wolfram A1 - Kanjee, J. A1 - Motukwa, G. A1 - Olonade, K. A1 - Dodoo, A. T1 - A snapshot review of future‑oriented standards for cement, admixtures, and concrete: How Africa can spearhead the implementation of green urban construction materials N2 - The existing cement and concrete standards are not capable of making full use of the current technology capacity due to strong focus on conventional concrete and thus they are not fit for the current and future challenges of construction industry. The paper highlights shortcomings with regard to the implementation of the existing standards. It can be seen that future-oriented standards are generally required to contribute to a lower-carbon footprint of the industry. These changes are significantly more relevant in sub-Saharan Africa, due to the rapidly increasing urbanisation challenge and the enormous potentials to develop lower-carbon technologies than elsewhere in the world. KW - Future‑oriented standards KW - Green urban construction KW - Cement PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582563 DO - https://doi.org/10.1557/s43580-023-00563-9 SN - 2731-5894 VL - 4 IS - 8 SP - 557 EP - 565 PB - Springer International Publishing CY - Springer Nature Switzerland, Cham AN - OPUS4-58256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Christian A1 - Thore, Johannes A1 - Clozel, Mélanie A1 - Günster, Jens A1 - Wilbig, Janka A1 - Meyer, Andreas T1 - Additive manufacturing of metallic glass from powder in space N2 - Additive manufacturing of metals – and in particular building with laser-based powder bed fusion – is highly flexible and allows high-resolution features and feedstock savings. Meanwhile, though space stations in low Earth orbit are established, a set of visits to the Moon have been performed, and humankind can send out rovers to explore Venus and Mars, none of these milestone missions is equipped with technology to manufacture functional metallic parts or tools in space. In order to advance space exploration to long-term missions beyond low Earth orbit, it will be crucial to develop and employ technology for in-space manufacturing (ISM) and in-situ resource utilisation (ISRU). To use the advantages of laser-based powder bed fusion in these endeavours, the challenge of powder handling in microgravity must be met. Here we present a device capable of building parts using metallic powders in microgravity. This was proven on several sounding rocket flights, on which occasions Zr-based metallic glass parts produced by additive manufacturing in space were built. The findings of this work demonstrate that building parts using powder feedstock, which is more compact to transport into space than wire, is possible in microgravity environments. This thus significantly advances ISRU and ISM and paves the way for future tests in prolonged microgravity settings. KW - Metallic Glass KW - Additive Manufacturing KW - Space PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600667 DO - https://doi.org/10.1038/s41526-023-00327-7 VL - 9 SP - 1 EP - 9 PB - Springer Nature AN - OPUS4-60066 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ecke, Alexander A1 - Bell, Jérémy A1 - Schneider, Rudolf T1 - A three-dimensional microfluidic flow cell and system integration for improved electrochemical substrate detection in HRP/TMB-based immunoassays N2 - Immunoassays, based on the recognition and capture of analytes by highly selective antibodies, are now used extensively in all areas of diagnostics, but the challenge is to further integrate them into online sensors. To improve the transition from laboratory immunoassays to immunosensors, we have developed a complete flow system, based on a microfluidic core flow cell to enable automated detection of one of the most commonly used immunoassay substrates, TMB, by chronoamperometry. The architecture and fluidic optimisation of the system showed that a specially designed 3D flow cell allows higher flow rates (500 μL min−1) than a standard enlarged microfluidic channel (50 μL min−1) resulting in a significantly shorter detection time of 30 seconds per sample and making the system more robust against interferences due to bubble formation in the chip. The electrochemical measurements showed an improved signal-to-noise ratio (SNR) and thus higher sensitivity for a model immunoassay for diclofenac (SNR = 59), compared to the analytical performance of a conventional laboratory microplate-based assay with optical detection (SNR = 19). In general, this system facilitates the conversion of any conventional immunoassay into an immunosensor with automatic and continuous detection. KW - Microfluidic KW - Immunoassay KW - Electrochemical KW - Mikrofluidik KW - Immunassay KW - Elektrochemie PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580159 DO - https://doi.org/10.1039/d3sd00095h VL - 2 SP - 887 EP - 892 PB - Royal Society of Chemistry CY - London, United Kingdom AN - OPUS4-58015 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Raysyan, Anna A1 - Zwigart, S. A1 - Eremin, S. A. A1 - Schneider, Rudolf T1 - BPA Endocrine Disruptor Detection at the Cutting Edge: FPIA and ELISA Immunoassays N2 - BPA is a chemical commonly used in the production of polymer-based materials that can have detrimental effects on the thyroid gland and impact human reproductive health. Various expensive methods, such as liquid and gas chromatography, have been suggested for detecting BPA. The fluorescence polarization immunoassay (FPIA) is an inexpensive and efficient homogeneous mix-and-read method that allows for high-throughput screening. FPIA offers high specificity and sensitivity and can be carried out in a single phase within a timeframe of 20–30 min. In this study, new tracer molecules were designed that linked the fluorescein fluorophore with and without a spacer to the bisphenol A moiety. To assess the influence of the C6 spacer on the sensitivity of an assay based on the respective antibody, hapten–protein conjugates were synthesized and assessed for performance in an ELISA setup, and this resulted in a highly sensitive assay with a detection limit of 0.05 µg/L. The lowest limit of detection was reached by employing the spacer derivate in the FPIA and was 1.0 µg/L, working range from 2 to 155 µg/L. The validation of the methods was conducted using actual samples compared to LC–MS/MS, which served as the reference method. The FPIA and ELISA both demonstrated satisfactory concordance. KW - Fluorescence Polarization KW - Enzyme-Linked Immunosorbent Assay KW - Endokriner Disruptor KW - Bisphenol A KW - Freisetzung PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579497 DO - https://doi.org/10.3390/bios13060664 VL - 13 IS - 6 SP - 1 EP - 12 PB - MDPI CY - Basel AN - OPUS4-57949 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Filimonova, S. M. A1 - Melnikov, E. S. A1 - Kaufmann, Jan Ole A1 - Shchepochkina, O. Y. A1 - Eremin, S. A. A1 - Gravel, I. V. A1 - Raysyan, Anna T1 - Exploring the anti‐α‐amylase activity of flavonoid aglycones in fabaceae plant extracts: a combined MALDI‐TOF‐MS and LC–MS/MS approach N2 - A combination of TLC-bioautography, MALDI-TOF-MS and LC–MS/MS methods was used to identify flavonoids with anti-α-amylase activity in extracts of Lathyrus pratensis L. (herb), L. polyphillus L. (fruits), Thermopsis lanceolata R. Br. (herb) and S. japonica L. (buds). After the TLC-autobiography assay, substances with anti-amylase activity were identified by MALDI-TOF-MS followed by confirmation of the result by LC–MS/MS. Results of the study revealed that the flavonoids apigenin, luteolin, formononetin, genistein and kaempferol display marked anti-α-amylase activity. Formononetin showed the largest activity. Compared with LC–MS/MS, MALDI-TOF-MS is a quick and convenient method; results can be obtained within minutes; and only minor sample amounts are required which allows us to analyse mixtures of substances without preliminary separation. However, the inability to distinguish between isomers is the main limitation of the method. KW - Enzyme KW - MALDI-TOF-MS KW - LC-MS/MS KW - Massenspektrometrie PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-577128 DO - https://doi.org/https://doi.org/10.1111/ijfs.16491 SN - 0950-5423 VL - 58 IS - 7 SP - 3902 EP - 3911 PB - Wiley & Sons CY - Hoboken, NJ, USA AN - OPUS4-57712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riedel, Soraya A1 - Jaut, Valerie A1 - Schneider, Rudolf T1 - Ergometrine sensing in rye flour by a magnetic bead-based immunoassay followed by flow injection analysis with amperometric detection N2 - A certain group of mycotoxins, the ergot alkaloids, has caused countless deaths throughout human history. They are found in rye and other cereals and ingesting contaminated foods can cause serious health problems. To identify contaminated food exceeding the legal limits for ergot alkaloids, a portable and cost-effective test system is of great interest to the food industry. Rapid analysis can be achieved by screening for a marker compound, for which we chose ergometrine. We developed a magnetic bead-based immunoassay for ergometrine with amperometric detection in a flow injection system using a handheld potentiostat and a smartphone. With this assay a limit of detection of 3 nM (1 μg/L) was achieved. In spiked rye flour, ergometrine levels from 25 to 250 μg/kg could be quantified. All results could be verified by optical detection. The developed assay offers great promise to meet the demand for on-site ergometrine detection in the food industry. KW - Ergot alkaloids KW - Amperometry KW - Magnetic beads KW - Immunoassay KW - Food analysis KW - Fow injection analysis KW - Mycotoxins PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565906 DO - https://doi.org/10.1016/j.talanta.2022.124172 SN - 0039-9140 N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S. VL - 254 IS - 124172 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-56590 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bühler, M. M. A1 - Hollenbach, P. A1 - Michalski, A. A1 - Meyer, S. A1 - Birle, E. A1 - Off, R. A1 - Lang, Ch. A1 - Schmidt, Wolfram A1 - Cudmani, R. A1 - Fritz, O. A1 - Baltes, G. A1 - Kortmann, G. T1 - The Industrialisation of Sustainable Construction: A Transdisciplinary Approach to the Large-Scale Introduction of Compacted Mineral Mixtures (CMMs) into Building Construction N2 - Abstract: Increasing demand for sustainable, resilient, and low-carbon construction materials has highlighted the potential of Compacted Mineral Mixtures (CMMs), which are formulated from various soil types (sand, silt, clay) and recycled mineral waste. This paper presents a comprehensive inter- and transdisciplinary research concept that aims to industrialise and scale up the adoption of CMM-based construction materials and methods, thereby accelerating the construction industry’s systemic transition towards carbon neutrality. By drawing upon the latest advances in soil mechanics, rheology, and automation, we propose the development of a robust material properties database to inform the design and application of CMM-based materials, taking into account their complex, time-dependent behaviour. Advanced soil mechanical tests would be utilised to ensure optimal performance under various loading and ageing conditions. This research has also recognised the importance of context-specific strategies for CMM adoption. We have explored the implications and limitations of implementing the proposed framework in developing countries, particularly where resources may be constrained. We aim to shed light on socio-economic and regulatory aspects that could influence the adoption of these sustainable construction methods. The proposed concept explores how the automated production of CMM-based wall elements can become a fast, competitive, emission-free, and recyclable alternative to traditional masonry and concrete construction techniques. We advocate for the integration of open-source digital platform technologies to enhance data accessibility, processing, and knowledge acquisition; to boost confidence in CMM-based technologies; and to catalyse their widespread adoption. We believe that the transformative potential of this research necessitates a blend of basic and applied investigation using a comprehensive, holistic, and transfer-oriented methodology. Thus, this paper serves to highlight the viability and multiple benefits of CMMs in construction, emphasising their pivotal role in advancing sustainable development and resilience in the built environment. KW - Decarbonisation KW - Circular economy KW - Recycled materials KW - Demolition wastes KW - Low-carbon construction KW - Building with earth KW - Compressed earth KW - Rammed earth KW - Sustainable construction PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-583260 DO - https://doi.org/10.3390/su151310677 VL - 15 IS - 13 SP - 1 EP - 25 PB - MDPI AN - OPUS4-58326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mezhov, Alexander A1 - Kulisch, D. A1 - Goncharov, A. A1 - Zhutovsky, S. T1 - A Comparative Study of Factors Influencing Hydration Stoppage of Hardened Cement Paste N2 - There is no consensus on which hydration stoppage method is optimal to preserve the microstructure and mineral composition of samples, especially considering the specific aspects of different testing methods, such as TGA, MIP, or XRD. This paper presents a quantitative comparison between the most popular hydration stoppage strategies and parameters such as the sample piece size, the soaking time in a solvent, and the type, as examined on cement paste hydrated for 7 days. It was found that the carbonation appears either for samples smaller than 2.36 mm and bigger than 4.75 mm or samples soaked in a solvent for longer than 1 h. Fast solvent replacement leads to ettringite diminution and total pore volume increase. Among others, solvent replacement with subsequent gentle heating under a vacuum was found to be the most efficient, whereas it was experimentally demonstrated that isopropyl alcohol stops hydration faster than ethanol and acetone. KW - Hydration stoppage KW - Solvent replacement KW - Soaking time KW - Sample piece size PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582430 DO - https://doi.org/10.3390/su15021080 VL - 15 IS - 2 SP - 1 EP - 21 PB - MDPI CY - Basel, Switzerland. AN - OPUS4-58243 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kruschwitz, Sabine A1 - Munsch, Sarah A1 - Telong, Melissa A1 - Schmidt, Wolfram A1 - Bintz, Thilo A1 - Fladt, Matthias A1 - Stelzner, Ludwig T1 - The NMR core analyzing TOMograph: A multi-functional tool for non-destructive testing of building materials N2 - NMR is becoming increasingly popular for the investigation of building materials as it is a non-invasive technology that does not require any sample preparation nor causes damage to the material. Depending on the specific application it can offer insights into properties like porosity and spatial saturation degree as well as pore structure. Moreover it enables the determination of moisture transport properties and the (re-)distribution of internal moisture into different reservoirs or chemical phases upon damage and curing. However, as yet most investigations were carried out using devices originally either designed for geophysical applications or the analysis of rather homogeneous small scale (< 10 mL) samples. This paper describes the capabilities of an NMR tomograph, which has been specifically optimized for the investigation of larger, heterogeneous building material samples (diameters of up to 72 mm, length of up to 700 mm) with a high flexibility due to interchangeable coils allowing for a high SNR and short echo times (50 - 80 m s). KW - Fire spalling KW - Moisture transport KW - Concrete KW - Cement hydration KW - Sensitivity KW - Supplementary cementitous materials KW - Frost salt attack PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573755 DO - https://doi.org/10.1016/j.mrl.2023.03.004 SN - 2097-0048 VL - 3 IS - 3 SP - 207 EP - 219 PB - Elsevier B.V. AN - OPUS4-57375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pott, U. A1 - Crasselt, Claudia A1 - Fobbe, N. A1 - Haist, M. A1 - Heinemann, M. A1 - Hellmann, S. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Lei, L. A1 - Li, R. A1 - Link, J. A1 - Lowke, D. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Nicia, D. A1 - Plank, J. A1 - Reißig, S. A1 - Schäfer, T. A1 - Schilde, C. A1 - Schmidt, Wolfram A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Strybny, B. A1 - Ukrainczyk, N. A1 - Wolf, J. A1 - Xiao, P. A1 - Stephan, D. T1 - Characterization data of reference materials used for phase II of the priority program DFG SPP 2005 “Opus Fluidum Futurum –Rheology of reactive, multiscale, multiphase construction materials” N2 - A thorough characterization of base materials is the prereq- uisite for further research. In this paper, the characterization data of the reference materials (CEM I 42.5 R, limestone pow- der, calcined clay and a mixture of these three components) used in the second funding phase of the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented under the aspects of chemical and min- eralogical composition as well as physical and chemical properties. The data were collected based on tests performed by up to eleven research groups involved in this cooperative program. KW - Portland cement KW - Limestone powder KW - Calcined clay KW - Sustainable cement KW - DFG SPP 2005 PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569913 DO - https://doi.org/10.1016/j.dib.2023.108902 VL - 47 SP - 1 EP - 19 PB - Elsevier AN - OPUS4-56991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Robens-Radermacher, Annika A1 - Unger, Jörg F. A1 - Mezhov, Alexander A1 - Schmidt, Wolfram ED - Biondini, F. ED - Frangopo, D. M. T1 - Temperature dependent modelling approach for early age behavior of printable mortars N2 - Structural build-up describes the stability and early-age strength development of fresh mortar used in 3D printing. lt is influenced by several factors, i.e. the composition of the print­ able material, the printing regime, and the ambient conditions. The existing modelling approaches for structural build-up usually define the model parameters for a specific material composition with­ out considering the influence of the ambient conditions. The goal of this contribution is to explicitly include the temperature dependency in the modelling approach. Temperature changes have signifi­ cant impact on the structural build-up process: an increase of the temperature leads to a faster dissol­ ution of cement phases and accelerates hydration. The proposed extended model includes temperature dependency using the Arrhenius theory. The new model parameters are successfully calibrated based on Viskomat measurement data using Bayesian inference. Furthermore, a higher impact of the temperature in the re-flocculation as in the structuration stage is observed. T2 - The Eighth International Symposium on Life-Cycle Civil Engineering (IALCCE 2023) CY - Milano, Italien DA - 02.07.2023 KW - 3D concrete printing KW - Material characterization KW - Structural build-up KW - Thixotropy KW - Model calibration PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582175 SN - 978-1-003-32302-0 DO - https://doi.org/10.1201/9781003323020-146 SN - 978-1-003-32302-0 VL - 1st Edition SP - 1193 EP - 1200 PB - CRC Press AN - OPUS4-58217 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reinmuth-Selzle, K. A1 - Bellinghausen, I. A1 - Leifke, A. L. A1 - Backes, A. T. A1 - Bothen, N. A1 - Ziegler, K. A1 - Weller, Michael G. A1 - Saloga, J. A1 - Schuppan, D. A1 - Lucas, K. A1 - Pöschl, U. A1 - Fröhlich-Nowoisky, J. T1 - Chemical modification by peroxynitrite enhances TLR4 activation of the grass pollen allergen Phl p 5 N2 - The chemical modification of aeroallergens by reactive oxygen and nitrogen species (ROS/RNS) may contribute to the growing prevalence of respiratory allergies in industrialized countries. Post-translational modifications can alter the immunological properties of proteins, but the underlying mechanisms and effects are not well understood. In this study, we investigate the Toll-like receptor 4 (TLR4) activation of the major birch and grass pollen allergens Bet v 1 and Phl p 5, and how the physiological oxidant peroxynitrite (ONOO–) changes the TLR4 activation through protein nitration and the formation of protein dimers and higher oligomers. Of the two allergens, Bet v 1 exhibited no TLR4 activation, but we found TLR4 activation of Phl p 5, which increased after modification with ONOO– and may play a role in the sensitization against this grass pollen allergen. We attribute the TLR4 activation mainly to the two-domain structure of Phl p 5 which may promote TLR4 dimerization and activation. The enhanced TLR4 signaling of the modified allergen indicates that the ONOO–-induced modifications affect relevant protein-receptor interactions. This may lead to increased sensitization to the grass pollen allergen and thus contribute to the increasing prevalence of allergies in the Anthropocene, the present era of globally pervasive anthropogenic influence on the environment. KW - Bet v 1 KW - Birch pollen allergen KW - Phl p 5 KW - Grass pollen KW - Phleum pratense KW - Betula pendula KW - Nitration KW - Nitrotyrosine KW - Protein nitration KW - Toll-like receptor 4 KW - Allergy KW - Enhancement KW - Oligomerization KW - Dimerization KW - TLR4 activation KW - Air pollution KW - Nitrogen oxides KW - Inflammation PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570298 DO - https://doi.org/10.3389/falgy.2023.1066392 VL - 4 SP - 1 EP - 7 PB - Frontiers Media SA CY - Lausanne, Switzerland AN - OPUS4-57029 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Beslic, D. A1 - Tscheuschner, Georg A1 - Renard, B. Y. A1 - Weller, Michael G. A1 - Muth, Thilo T1 - Comprehensive evaluation of peptide de novo sequencing tools for monoclonal antibody assembly N2 - Monoclonal antibodies are biotechnologically produced proteins with various applications in research, therapeutics and diagnostics. Their ability to recognize and bind to specific molecule structures makes them essential research tools and therapeutic agents. Sequence information of antibodies is helpful for understanding antibody–antigen interactions and ensuring their affinity and specificity. De novo protein sequencing based on mass spectrometry is a valuable method to obtain the amino acid sequence of peptides and proteins without a priori knowledge. In this study, we evaluated six recently developed de novo peptide sequencing algorithms (Novor, pNovo 3, DeepNovo, SMSNet, PointNovo and Casanovo), which were not specifically designed for antibody data. We validated their ability to identify and assemble antibody sequences on three multi-enzymatic data sets. The deep learning-based tools Casanovo and PointNovo showed an increased peptide recall across different enzymes and data sets compared with spectrum-graph-based approaches. We evaluated different error types of de novo peptide sequencing tools and their performance for different numbers of missing cleavage sites, noisy spectra and peptides of various lengths. We achieved a sequence coverage of 97.69–99.53% on the light chains of three different antibody data sets using the de Bruijn assembler ALPS and the predictions from Casanovo. However, low sequence coverage and accuracy on the heavy chains demonstrate that complete de novo protein sequencing remains a challenging issue in proteomics that requires improved de novo error correction, alternative digestion strategies and hybrid approaches such as homology search to achieve high accuracy on long protein sequences. KW - De novo peptide sequencing KW - Bioinformatics KW - Benchmarking study KW - Monoclonal antibody KW - Mass spectrometry KW - Sequence coverage KW - Light chains KW - Heavy chains KW - IgG KW - Immunoglobulins KW - Error correction KW - Sequencing algorithm KW - Preprocessing KW - Missing fragmentation sites KW - Deep learning-based tools PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570363 DO - https://doi.org/10.1093/bib/bbac542 VL - 24 IS - 1 SP - 1 EP - 12 PB - Oxford University Press AN - OPUS4-57036 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bennet, Francesca A1 - Opitz, R. A1 - Ghoreishi, N. A1 - Plate, K. A1 - Barnes, J.-P. A1 - Bellew, A. A1 - Bellu, A. A1 - Ceccone, G. A1 - de Vito, E. A1 - Delcorte, A. A1 - Franquet, A. A1 - Fumageli, F. A1 - Gilliland, D. A1 - Jungnickel, H. A1 - Lee, T.G. A1 - Poleunis, C. A1 - Rading, D. A1 - Shon, H.K. A1 - Spampinato, V. A1 - Son, J.G. A1 - Wang, F. A1 - Wang, Y.-C. A. A1 - Zhao, Y. A1 - Roloff, A. A1 - Tentschert, J. A1 - Radnik, Jörg T1 - VAMAS TWA2 interlaboratory comparison: Surface analysis of TiO2 nanoparticles using ToF-SIMS N2 - Due to the extremely high specific surface area of nanoparticles and corresponding potential for adsorption, the results of surface analysis can be highly dependent on the history of the particles, particularly regarding sample preparation and storage. The sample preparation method has, therefore, the potential to have a significant influence on the results. This report describes an interlaboratory comparison (ILC) with the aim of assessing which sample preparation methods for ToF-SIMS analysis of nanoparticles provided the most intra- and interlaboratory consistency and the least amount of sample contamination. The BAM reference material BAM-P110 (TiO2 nanoparticles with a mean Feret diameter of 19 nm) was used as a sample representing typical nanoparticles. A total of 11 participants returned ToF-SIMS data,in positive and (optionally) negative polarity, using sample preparation methods of “stick-and-go” as well as optionally “drop-dry” and “spin-coat.” The results showed that the largest sources of variation within the entire data set were caused by adventitious hydrocarbon contamination or insufficient sample coverage, with the spin-coating protocol applied in this ILC showing a tendency toward insufficient sample coverage; the sample preparation method or the participant had a lesser influence on results. KW - Secondary Ion Mass Spectrometry KW - VMAAS KW - Titania KW - Interlaboratory comparison KW - Reproducibility PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582290 DO - https://doi.org/10.1116/6.0002814 SN - 0734-2101 VL - 41 IS - 5 SP - 053210-1 EP - 053210-13 PB - AIP (American Institute of Physics) AN - OPUS4-58229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Kai A1 - Mirabella, Francesca A1 - Knigge, Xenia A1 - Mezera, Marek A1 - Weise, Matthias A1 - Sahre, Mario A1 - Wasmuth, Karsten A1 - Voss, Heike A1 - Hertwig, Andreas A1 - Krüger, Jörg A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Bonse, Jörn T1 - Chemical and topographical changes upon sub-100-nm laser-induced periodic surface structure formation on titanium alloy: the influence of laser pulse repetition rate and number of over-scans N2 - Titanium and its alloys are known to allow the straightforward laser-based manufacturing of ordered surface nanostructures, so-called high spatial frequency laser-induced periodic surface structures (HSFL). These structures exhibit sub-100 nm spatial periods – far below the optical diffraction limit. The resulting surface functionalities are usually enabled by both, topographic and chemical alterations of the nanostructured surfaces. For exploring these effects, multi-method characterizations were performed here for HSFL processed on Ti–6Al–4V alloy upon irradiation with near-infrared ps-laser pulses (1030 nm, ≈1 ps pulse duration, 1–400 kHz) under different laser scan processing conditions, i.e., by systematically varying the pulse repetition frequency and the number of laser irradiation passes. The sample characterization involved morphological and topographical investigations by scanning electron microscopy (SEM), atomic force microscopy (AFM), tactile stylus profilometry, as well as near-surface chemical analyses hard X-ray photoelectron spectroscopy (HAXPES) and depth-profiling time-of-flight secondary ion mass spectrometry (ToF-SIMS). This provides a quantification of the laser ablation depth, the geometrical HSFL characteristics and enables new insights into the depth extent and the nature of the non-ablative laser-induced near-surface oxidation accompanying these nanostructures. This allows to answer the questions how the processing of HSFL can be industrially scaled up, and whether the latter is limited by heat-accumulation effects. T2 - 2023 E-MRS Spring Meeting, Symposium L "Making light matter: lasers in material sciences and photonics" CY - Strasbourg, France DA - 29.05.2023 KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrashort laser pulses KW - Laser processing KW - Hard X-ray photoelectron spectroscopy (HAXPES) KW - Time-of-flight secondary ion mass spectrometry (ToF-SIMS) PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589902 UR - https://onlinelibrary.wiley.com/doi/full/10.1002/pssa.202300719 DO - https://doi.org/10.1002/pssa.202300719 SN - 1862-6319 VL - 220 SP - 1 EP - 12 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-58990 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lozano-Martín, D. A1 - Tuma, Dirk A1 - Kipphardt, Heinrich A1 - Khanipour, Peyman A1 - Chamorro, C. R. T1 - Thermodynamic characterization of the (H2 + C3H8) system significant for the hydrogen economy: Experimental (p, rho, T) determination and equation-of-state modelling N2 - For the gradual introduction of hydrogen in the energy market, the study of the properties of mixtures of hydrogen with typical components of natural gas (NG) and liquefied petroleum gas (LPG) is of great importance. This work aims to provide accurate experimental (p, rho, T) data for three hydrogen-propane mixtures with nominal compositions (amount of substance, mol/mol) of (0.95 H2 + 0.05 C3H8), (0.90 H2 + 0.10 C3H8), and (0.83 H2 + 0.17 C3H8), at temperatures of 250, 275, 300, 325, 350, and 375 K, and pressures up to 20 MPa. A single-sinker densimeter was used to determine the density of the mixtures. Experimental density data were compared to the densities calculated from two reference equations of state: the GERG-2008 and the AGA8-DC92. Relative deviations from the GERG-2008 EoS are systematically larger than those from the AGA8-DC92. They are within the ±0.5% band for the mixture with 5% of propane, but deviations are higher than 0.5% for the mixtures with 10% and 17% of propane, especially at low temperatures and high pressures. Finally, the sets of new experimental data have been processed by the application of two different statistical equations of state: the virial equation of state, through the second and third virial coefficients, B(T, x) and C(T, x), and the PC-SAFT equation of state. KW - Hydrogen-containing gas mixture KW - Density data KW - Equation of state KW - Virial coefficients PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570056 DO - https://doi.org/10.1016/j.ijhydene.2022.11.170 SN - 0360-3199 VL - 48 IS - 23 SP - 8645 EP - 8667 PB - Elsevier B. V. CY - Amsterdam AN - OPUS4-57005 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klippel, A. A1 - Hofmann-Böllinghaus, Anja A1 - Gnutzmann, Tanja A1 - Piechnik, K. T1 - Reaction-to-fire testing of bus interior materials: Assessing burning behaviour and smoke gas toxicity N2 - Although fire safety regulations for buses have been adapted in recent years regarding, for example, fire detection and engine fire suppression systems, the changes in regulations for bus interior materials are minimal. A comparison of fire safety regulations for interior materials in other transport sectors for trains, ships or aircraft reveals a much lower level of requirements for bus materials. Although repeated bus accidents as well as fire statistics show the danger a bus fire can pose to passengers. In particular, the combination of a fire incident and passengers with reduced mobility led to severe disasters in Germany and other European countries. To enhance the fire safety for passengers, the interior bus materials are crucial as the fire development in the bus cabin determines whether escape and rescue is possible. Against this background, bus interior materials were tested in different fire test scenarios. Measurement of a wide variety of parameters, for example, the mass loss, ignition time, smoke gas composition, heat release rate among others were carried out. Tested materials complied to the newest set of requirements. For this purpose, interior materials and their components had to be identified according to their chemical structure. Parts of the tests were funded by BASt (Federal Highway Research Institute) in the project 82.0723/2018. Experimental results show reaction-to-fire behaviour which lead to very limited times for escape and rescue in case of fire in a bus cabin. Based on the studies on fire behaviour and toxicity assessment, recommendations for improved fire safety regulations for interior materials could be made. KW - Burning behaviour KW - Bus interior materials KW - Cone calorimeter KW - DIN tube furnace KW - FTIR spectroscopy KW - Reference values KW - Smoke toxicity PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576085 DO - https://doi.org/10.1002/fam.3108 SN - 1099-1018 VL - 47 IS - 5 SP - 665 EP - 680 PB - Wiley CY - New York, NY AN - OPUS4-57608 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manes, M. A1 - El Houssami, M. A1 - Campbell, R. A1 - Sauca, A. A1 - Rush, D. A1 - Hofmann-Böllinghaus, Anja A1 - Andersson, P. A1 - Wagner, P. A1 - Veeneklaas, J. A1 - van Hees, P. A1 - Guillaume, E. T1 - Closing Data Gaps and Paving the Way for Pan-European Fire Safety Efforts: Part I—Overview of Current Practices for Fire Statistics N2 - The analysis of the current state of fire statistics and data collection in Europe and other countries is needed to increase awareness of how fire incidents affect buildings and to support pan-European fire prevention and fire mitigation measures. The terminology and data collected regarding fire incidents in buildings in the EU Member States were mapped to obtain meaningful datasets to determine common terminology, collection methodology, and data interpretation system. An extensive literature review showed that fire data collection systems have been instrumental in informing firefighting strategies, evidence-based planning, prevention, and educational programmes. Differences and similarities between fire data collection systems were also investigated. The amount and quality of the information in fire statistical recording systems appear to be influenced by the complexity and structure with which the data are collected. The analysis also examined the existing fire statistics in the EU Member States and a few other countries. Finally, a detailed investigation of the number of fires, fire deaths, and injuries from 2009 to 2018 in several countries was examined based on data from a report by CTIF. The trends showed differences attributable to the existing fire statistical practices in terms of terminology and data collection, and interpretation. Part II proposes a common terminology for selected fire statistical variables. The results provide relevant information regarding fire safety at the European level and should be used to guide the development of more uniform fire statistics across Europe. KW - Fire statistics KW - European project PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575711 DO - https://doi.org/10.1007/s10694-023-01415-6 SN - 1572-8099 SP - 1 EP - 44 PB - Springer CY - Heidelberg AN - OPUS4-57571 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - El Houssami, M. A1 - Försth, M. A1 - Fredriksson, H. A1 - Drean, V. A1 - Guillaume, E. A1 - Hofmann-Böllinghaus, Anja A1 - Sandinge, A. T1 - Fire safety of interior materials of buses N2 - This study provides an analysis on the fire safety of passengers and the fire protection of coaches and buses. A brief review of major bus fire incidents, an overview of current regulations in Europe, and their limitations are presented. The study finds that the current small-scale fire test methods described in UN ECE Reg No. 118 need to be replaced by test methods that can assess the reaction to fire of materials when exposed to ignition sources of varying sizes. To address these shortcomings, the study proposed an expert recommendation to update the material fire safety requirements and testing for buses. Additional measures are proposed, derived from objectives and strategies applied in other transport sectors, and can be tested through existing European and international standards, which are widely used by several industries. These measures aim to extend the time with tenable conditions for a safe evacuation in case of fire, reduce the degree of damage to buses, reduce the risk for fast and excessive thermal exposure on modern energy carriers needed for a more sustainable transport sector. KW - Fire KW - Bus interior materials KW - Rregulations PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575700 DO - https://doi.org/10.1002/fam.3134 SN - 1099-1018 SP - 1 EP - 15 PB - Wiley CY - London AN - OPUS4-57570 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manes, M. A1 - Sauca, A. A1 - El Houssami, M. A1 - Andersson, P. A1 - McIntyre, C. A1 - Campbell, R. A1 - Rush, D. A1 - Hofmann-Böllinghaus, Anja A1 - Wagner, P. A1 - Leene, M. A1 - Oberhagemann, D. A1 - Jomaas, G. A1 - Grone, F. A1 - Guillaume, E. T1 - Closing Data Gaps and Paving the Way for Pan-European Fire Safety Efforts: Part II—Terminology of Fire Statistical Variables N2 - A well-defined terminology of fire-related variables is important for correct analyses and supporting knowledge-based decisions regarding the evaluation of building fires at the European level. After developing an overview of current practices for fire statistics in Part I, the terminology used and the data collected by the EU Member States and eight other countries regarding fire incidents, property damage and human losses were mapped to increase awareness of their practice and support a comprehensive assessment of several fire statistical datasets. A questionnaire was distributed to relevant authorities responsible for the collection, elaboration/analysis, and fire statistical data publications to define and select the essential variables for an appropriate fire assessment and fire incident description. Based on the results of the questionnaire able to identify the essential fire statistical variables and a detailed analysis of current definitions adopted in the fire statistics of the EU Member States and other countries, a common terminology is proposed to collect the necessary data in the EU Member States and obtain meaningful datasets based on standardised terms and definitions. The results will generate essential outputs to move towards harmonised fire statistics at the EU level and contribute to an appropriate analysis able to improve fire prevention and fire mitigation in building fires. KW - Fire statistics PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575725 DO - https://doi.org/10.1007/s10694-023-01408-5 SN - 1572-8099 SP - 1 EP - 32 PB - Springer CY - Heidelberg AN - OPUS4-57572 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tang, Chi-Long A1 - Seeger, Stefan A1 - Röllig, Mathias T1 - Improving the comparability of FFF-3D printing emission data by adjustment of the set extruder temperature N2 - Fused filament fabrication (FFF) is a material extrusion-based technique often used in desktop 3D printers. Polymeric filaments are melted and are extruded through a heated nozzle to form a 3D object in layers. The extruder temperature is therefore a key parameter for a successful print job but also one of the main emission driving factors as harmful pollutants (e.g., ultrafine particles) are formed by thermal polymer degradation. The awareness of potential health risks has increased the number of emission studies in the past years. However, studies usually refer their calculated emission data to the printer set extruder temperature for comparison purposes. In this study, we used a thermocouple and an infrared camera to measure the actual extruder temperature and found significant temperature deviations to the displayed set temperature among printer models. Our result shows that printing the same filament feedstocks with three different printer models and with identical printer set temperature resulted in a variation in particle emission of around two orders of magnitude. A temperature adjustment has reduced the variation to approx. one order of magnitude. Thus, it is necessary to refer the measured emission data to the actual extruder temperature as it poses a more accurate comparison parameter for evaluation of the indoor air quality in user scenarios or for health risk assessments. KW - Ultrafine particles KW - Infrared thermography KW - Thermocouple KW - Indoor air quality KW - FFF-3D printer PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572842 DO - https://doi.org/10.1016/j.aeaoa.2023.100217 VL - 18 SP - 100217 PB - Elsevier Ltd. CY - Amsterdam, Niederlande AN - OPUS4-57284 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kader, A. A1 - Kaufmann, Jan Ole A1 - Mangarova, D. B. A1 - Moeckel, J. A1 - Adams, L. C. A1 - Brangsch, J. A1 - Heyl, J. L. A1 - Zhao, J. A1 - Verlemann, C. A1 - Karst, U. A1 - Collettini, F. A1 - Auer, T. A. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Collagen-specific molecular magnetic resonance imaging of prostate cancer N2 - Constant interactions between tumor cells and the extracellular matrix (ECM) influence the progression of prostate cancer (PCa). One of the key components of the ECM are collagen fibers, since they are responsible for the tissue stiffness, growth, adhesion, proliferation, migration, invasion/metastasis, cell signaling, and immune recruitment of tumor cells. To explore this molecular marker in the content of PCa, we investigated two different tumor volumes (500 mm3 and 1000 mm3) of a xenograft mouse model of PCa with molecular magnetic resonance imaging (MRI) using a collagen-specific probe. For in vivo MRI evaluation, T1-weighted sequences before and after probe administration were analyzed. No significant signal difference between the two tumor volumes could be found. However, we detected a significant difference between the signal intensity of the peripheral tumor area and the central area of the tumor, at both 500 mm3 (p < 0.01, n = 16) and at 1000 mm3 (p < 0.01, n = 16). The results of our histologic analyses confirmed the in vivo studies: There was no significant difference in the amount of collagen between the two tumor volumes (p > 0.05), but within the tumor, higher collagen expression was observed in the peripheral area compared with the central area of the tumor. Laser ablation with inductively coupled plasma mass spectrometry further confirmed these results. The 1000 mm3 tumors contained 2.8 +- 1.0% collagen and the 500 mm3 tumors contained 3.2 +- 1.2% (n = 16). There was a strong correlation between the in vivo MRI data and the ex vivo histological data (y = 0.068x + 1.1; R2 = 0.74) (n = 16). The results of elemental analysis by inductively coupled plasma mass spectrometry supported the MRI data (y = 3.82x + 0.56; R2 = 0.79; n = 7). MRI with the collagen-specific probe in PCa enables differentiation between different tumor areas. This may help to differentiate tumor from healthy tissue, potentially identifying tumor areas with a specific tumor biology. KW - Molecular imaging KW - Magnetic resonance imaging KW - MRI KW - Prostate cancer KW - Collagen KW - Laser ablation-inductively coupled plasma-mass spectroscopy KW - EP-3533 KW - Peptide probe KW - Gd-DOTA KW - Contrast agent KW - Tumor PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568449 DO - https://doi.org/10.3390/ijms24010711 SN - 1422-0067 SN - 1661-6596 VL - 24 IS - 1 SP - 1 EP - 13 PB - MDPI CY - Basel AN - OPUS4-56844 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tannenberg, Robert A1 - Paul, Martin A1 - Röder, Bettina A1 - Gande, S. L. A1 - Sreeramulu, S. A1 - Saxena, K. A1 - Richter, C. A1 - Schwalbe, H. A1 - Swart, C. A1 - Weller, Michael G. T1 - Chemiluminescence biosensor for the determination of cardiac troponin I (cTnI) N2 - Cardiac troponin I (cTnI) is a crucial biomarker for diagnosing cardiac vascular diseases, including acute myocardial infarction (AMI). This study presents a proof-of-concept chemiluminescence-based immunosensor for rapid and accurate measurement of cTnI, with the potential for online monitoring. The immunosensor incorporates a flow cell design and a sensitive complementary metal-oxide-semiconductor (CMOS) camera for optical readout. A microfluidic setup was established to enable selective and quasi-online determination of cTnI within ten minutes. The sensor was tested with recombinant cTnI in phosphate buffer, demonstrating measurements in the concentration range of 2–25 µg/L, with a limit of detection (LoD) of 0.6 µg/L (23 pmol/L) achieved using the optimized system. The immunosensor exhibited high selectivity, as no cross-reactivity was observed with other recombinant proteins such as cTnT and cTnC at a concentration of 16 µg/L. Measurements with diluted blood plasma and serum yielded an LoD of 60 µg/L (2.4 nmol/L) and 70 µg/L (2.9 nmol/L), respectively. This biosensor offers a promising approach for the rapid and sensitive detection of cTnI, contributing to the diagnosis and management of acute myocardial infarction and other cardiac vascular diseases. N2 - Das kardiale Troponin I (cTnI) ist ein wichtiger Biomarker für die Diagnose von Herz-Kreislauf-Erkrankungen, einschließlich des akuten Myokardinfarkts (AMI). In dieser Studie wird ein auf Chemilumineszenz basierender Immunsensor für die schnelle und genaue Messung von cTnI vorgestellt, der das Potenzial für eine Online-Überwachung hat. Der Immunsensor besteht aus einer Durchflusszelle und einer empfindlichen CMOS-Kamera (Complementary Metal-Oxide-Semiconductor) zur optischen Detektion. Es wurde ein mikrofluidischer Aufbau entwickelt, der eine selektive und quasi Online-Bestimmung von cTnI innerhalb von zehn Minuten ermöglicht. Der Sensor wurde mit rekombinantem cTnI in Phosphatpuffer getestet und zeigte einen Messbereich von 2-25 µg/L, wobei mit dem optimierten System eine Nachweisgrenze (LoD) von 0,6 µg/L (23 pmol/L) erreicht wurde. Der Immunsensor zeigte eine hohe Selektivität, da keine Kreuzreaktivität mit anderen rekombinanten Proteinen wie cTnT und cTnC bei einer Konzentration von 16 µg/L beobachtet wurde. Messungen mit verdünntem Blutplasma und Serum ergaben einen LoD von 60 µg/L (2,4 nmol/L) bzw. 70 µg/L (2,9 nmol/L). Dieser Biosensor bietet einen vielversprechenden Ansatz für den schnellen und empfindlichen Nachweis von cTnI, der zur Diagnose und Behandlung des akuten Myokardinfarkts und anderer kardialer Gefäßerkrankungen beitragen kann. KW - Acute myocardial infarction KW - Heart attack KW - Emergency KW - Diagnosis KW - Cardiac troponin KW - Biomarker KW - Immunosensor KW - Biosensor KW - Chemiluminescence KW - Luminol KW - Peroxidase KW - Monoclonal antibodies KW - Flow injection immunoassay KW - Immunometric assay KW - Immunometric biosensor KW - Microfluidic system KW - Monolithic column KW - Online biosensor PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575471 DO - https://doi.org/10.3390/bios13040455 SN - 2079-6374 VL - 13 IS - 4 SP - 1 EP - 20 PB - MDPI CY - Basel AN - OPUS4-57547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Völzke, Jule L. A1 - Smatty, Sarah A1 - Döring, Sarah A1 - Ewald, Shireen A1 - Oelze, Marcus A1 - Fratzke, Franziska A1 - Flemig, Sabine A1 - Konthur, Zoltán A1 - Weller, Michael G. T1 - Efficient Purification of Polyhistidine-Tagged Recombinant Proteins Using Functionalized Corundum Particles N2 - Immobilized metal affinity chromatography (IMAC) is a widely used technique for purifying polyhistidine-tagged recombinant proteins. However, it often has practical limitations that require complex optimizations and additional steps for purification. In this study, we introduce functionalized corundum particles as a novel, efficient, and economical method for purifying recombinant proteins in a column-free format. The corundum surface is modified with amino silane APTES, followed by EDTA dianhydride, and then loaded with nickel ions. We used the Kaiser test to monitor the modification process and ICP-MS to quantify the metal-binding capacity. To evaluate the system, we used His-tagged protein A/G (PAG) mixed with bovine serum albumin (BSA). The corundum particles exhibited a binding capacity of approximately 3 mg of protein per gram of corundum or 2.4 mg per 1 mL of corundum suspension. We also examined cytoplasm obtained from different E. coli strains as an example of a complex matrix. Varying the imidazole concentration in the loading and washing buffers showed that higher concentrations during loading improved purity. Even with sample volumes as large as one liter, we successfully isolated recombinant proteins down to a concentration of 1 µg/mL. We found higher purity levels with corundum when comparing the corundum material to standard Ni–NTA agarose beads. We successfully purified His6-MBP-mSA2, a fusion protein comprising monomeric streptavidin and maltose-binding protein, from E. coli cytoplasm, demonstrating the method's applicability. We also purified SARS-CoV-2-S-RBD-His8 expressed in human Expi293F cells, confirming its suitability for mammalian cell culture supernatants. The material cost of the nickel-loaded corundum material (without regeneration) is estimated to be less than 30 cents per gram of functionalized support or 10 cents per milligram of isolated protein. Another advantage of this system is the exceptional physical and chemical stability of corundum particles. Overall, we have demonstrated that this novel material offers an efficient, robust, and cost-effective purification platform for His-tagged proteins, even in challenging, complex matrices and large sample volumes with low product concentrations. This method has potential applications in both small laboratories and large-scale industrial settings. N2 - Die immobilisierte Metallaffinitätschromatographie (IMAC) ist eine weit verbreitete Technik zur Reinigung von rekombinanten Proteinen mit Polyhistidin-Markierung. Sie hat jedoch oft praktische Einschränkungen, die komplexe Optimierungen und zusätzliche Schritte für die Aufreinigung erfordern. In dieser Studie stellen wir funktionalisierte Korundpartikel als neuartige, effiziente und wirtschaftliche Methode zur Reinigung rekombinanter Proteine in einem säulenfreien Format vor. Die Korundoberfläche wird mit dem Aminosilan APTES und anschließend mit EDTA-Dianhydrid modifiziert und dann mit Nickelionen beladen. Wir haben den Kaiser-Test zur Überwachung des Modifizierungsprozesses und ICP-MS zur Quantifizierung der Metallbindungskapazität verwendet. Zur Charakterisierung des Systems verwendeten wir His-markiertes Protein A/G (PAG) in Kombination mit Rinderserumalbumin (BSA). Die Korundpartikel wiesen eine Bindungskapazität von etwa 3 mg Protein pro Gramm Korund oder 2,4 mg pro 1 ml Korundsuspension auf. Als Beispiel für eine komplexe Matrix untersuchten wir auch Zytoplasma, das aus verschiedenen E. coli-Stämmen gewonnen wurde. Die Variation der Imidazolkonzentration in den Lade- und Waschpuffern zeigte, dass höhere Konzentrationen beim Laden die Reinheit verbesserten. Selbst bei einem Probenvolumen von bis zu einem Liter konnten wir rekombinante Proteine von 1 µg/mL isolieren. Beim Vergleich des Korundmaterials mit Standard-Ni-NTA-Agarose-Beads stellten wir einen höheren Reinheitsgrad mit Korund fest. Wir reinigten erfolgreich His6-MBP-mSA2 aus E. coli-Zytoplasma, ein Fusionsprotein, das aus monomerem Streptavidin und Maltose-bindendem Protein besteht. Wir reinigten auch SARS-CoV-2-S-RBD-His8, das in humanen Expi293F-Zellen exprimiert wurde, und bestätigten damit die Eignung des Materials für Zellkulturüberstände von Säugetieren. Die Materialkosten für nickelbeladenen Korund (ohne Regenerierung) werden auf weniger als 30 Cent pro Gramm funktionalisierten Trägers oder 10 Cent pro Milligramm isolierten Proteins geschätzt. Ein weiterer Vorteil dieses Systems ist die außergewöhnliche physikalische und chemische Stabilität der Korundpartikel. Insgesamt haben wir gezeigt, dass dieses neuartige Material eine effiziente, robuste und kostengünstige Reinigungsplattform für His-markierte Proteine bietet, selbst bei schwierigen, komplexen Matrices und großen Probenmengen mit niedrigen Produktkonzentrationen. Diese Methode könnte sowohl in kleinen Labors als auch in der Großindustrie eingesetzt werden. KW - Aluminum oxide KW - Sapphire KW - Ethylenediaminetetraacetic acid KW - Nickel chelate KW - EDTAD KW - HexaHis-Tag KW - His6 KW - 6xHis KW - His8 KW - Bioseparation KW - IMAC purification KW - Immunocapture KW - Affinity chromatography KW - Carrier KW - Nickel KW - Recombinant protein KW - Escherichia coli KW - Bacterial lysates KW - Cytoplasm KW - Polishing KW - Downstream processing PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575672 DO - https://doi.org/10.3390/biotech12020031 VL - 12 IS - 2 SP - 1 EP - 18 PB - MDPI CY - Basel, Schweiz AN - OPUS4-57567 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fröhlich-Nowoisky, J. A1 - Bothen, N. A1 - Backes, A. T. A1 - Weller, Michael G. A1 - Pöschl, U. T1 - Oligomerization and tyrosine nitration enhance the allergenic potential of the birch and grass pollen allergens Bet v 1 and Phl p 5 N2 - Protein modifications such as oligomerization and tyrosine nitration alter the immune response to allergens and may contribute to the increasing prevalence of allergic diseases. In this mini-review, we summarize and discuss relevant findings for the major birch and grass pollen allergens Bet v 1 and Phl p 5 modified with tetranitromethane (laboratory studies), peroxynitrite (physiological processes), and ozone and nitrogen dioxide environmental conditions). We focus on tyrosine nitration and the formation of protein dimers and higher oligomers via dityrosine cross-linking and the immunological effects studied. N2 - Proteinmodifikationen wie Oligomerisierung und Tyrosinnitrierung verändern die Immunantwort auf Allergene und tragen möglicherweise zur zunehmenden Prävalenz allergischer Erkrankungen bei. In diesem Mini-Review fassen wir relevante Befunde zu den wichtigsten Birken- und Gräserpollenallergenen Bet v 1 und Phl p 5 zusammen, die mit Tetranitromethan (Laborstudien), Peroxynitrit (physiologische Prozesse) und Ozon und Stickstoffdioxid (Umweltbedingungen). Wir konzentrieren uns auf die Tyrosin-Nitrierung und die Bildung von Proteindimeren und höheren Oligomeren durch Dityrosin-Vernetzung und deren immunologischen Auswirkungen. KW - Allergy KW - Nitration KW - Protein oligomers KW - Air pollution KW - Ozone KW - Nitrogen oxides KW - Tyrosine KW - Nitrotyrosine KW - Dityrosine KW - Dityrosine crosslinking KW - Protein degradation KW - Neoepitopes KW - Neoallergen KW - IgE KW - Immunoglobulin E PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591453 DO - https://doi.org/10.3389/falgy.2023.1303943 VL - 4 SP - 1 EP - 8 PB - Frontiers Media CY - Switzerland AN - OPUS4-59145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiesner, Yosri A1 - Bednarz, Marius A1 - Braun, Ulrike A1 - Bannick, Claus Gerhard A1 - Ricking, Mathias A1 - Altmann, Korinna T1 - A promising approach to monitor microplastic masses in composts N2 - Inputs of plastic impurities into the environment via the application of fertilizers are regulated in Germany and the EU by means of ordinances. Robust and fast analytical methods are the basis of legal regulations. Currently, only macro- and large microplastic contents (>1 mm) are measured. Microplastics (1–1,000 µm), are not yet monitored. Thermal analytical methods are suitable for this purpose, which can determine the mass content and can also be operated fully automatically in routine mode. Thermal extraction desorption-gas chromatography/mass spectrometry (TED-GC/MS) allows the identification of polymers and the determination of mass contents in solid samples from natural environments. In accordance with the German or European Commission (EC) Fertiliser Ordinance, composting plants should be monitored for microplastic particles with this method in the future. In this context a compost plant was sampled. At the end of the rotting process, the compost was sieved and separated in a coarse (>1 mm) and a fine fraction (<1 mm). The fine fraction was processed using density separation comparing NaCl and NaI as possible salt alternative and screened for microplastic masses by TED-GC/MS with additional validation and quality assurance experiments. With TED-GC/MS total microplastics mass contents of 1.1–3.0 μg/mg in finished compost could be detected with polyethylene mainly. What differs much to the total mass of plastics in the coarse fraction with up to 60 μg/mg, which were visually searched, identified via ATR-FTIR and gravimetrically weighted. KW - Microplastics KW - TED-GC/MS KW - Compost KW - Monitoring KW - Soil PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586688 DO - https://doi.org/10.3389/fenvc.2023.1281558 SN - 2673-4486 VL - 4 SP - 1 EP - 12 PB - Frontiers Media CY - Lausanne AN - OPUS4-58668 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chemello, Giovanni A1 - Knigge, Xenia A1 - Ciornii, Dmitri A1 - Reed, B.P. A1 - Pollard, A.J. A1 - Clifford, C.A. A1 - Howe, T. A1 - Vyas, N. A1 - Hodoroaba, Vasile-Dan A1 - Radnik, Jörg T1 - Influence of the Morphology on the Functionalization of Graphene Nanoplatelets Analyzed by Comparative Photoelectron Spectroscopy with Soft and Hard X-Rays N2 - Since its isolation, graphene has received growing attention from academia and industry due to its unique properties. However, the “what is my material” barrier hinders further commercialization. X-ray photoelectron spectroscopy (XPS) is considered as a method of choice for the determination of the elemental and chemical composition. In this work the influence of the morphology of graphene particles on the XPS results is studied and investigated as a function of X-ray energy, using conventional XPS with Al K𝜶 radiation and hard X-ray photoemission spectroscopy (HAXPES) using Cr K𝜶 radiation. Thereby, the information depth is varied between 10 and 30 nm. For this purpose, two commercial powders containing graphene nanoplatelets with lateral dimensions of either ≈100 nm or in the micrometer range are compared. These larger ones exist as stack of graphene layers which is inspected with scanning electron microscopy. Both kinds of particles are then functionalized with either oxygen or fluorine. The size of the graphene particles is found to influence the degree of functionalization. Only the combination of XPS and HAXPES allows to detect the functionalization at the outermost surface of the particles or even of the stacks and to provide new insights into the functionalization process. KW - Functionalized graphene KW - Hard-energy X-ray photoelectron spectroscopy KW - X-ray photoelectron spectroscopy PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-578860 DO - https://doi.org/10.1002/admi.202300116 SN - 2196-7350 SP - 1 EP - 8 PB - Wiley VCH AN - OPUS4-57886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hahn, Marc Benjamin T1 - Accessing radiation damage to biomolecules on the nanoscale by particle-scattering simulations N2 - Radiation damage to DNA plays a central role in radiation therapy to cure cancer. The physico-chemical and biological processes involved encompass huge time and spatial scales. To obtain a comprehensive understanding on the nano and the macro scale is a very challenging tasks for experimental techniques alone. Therefore particle-scattering simulations are often applied to complement measurements and aide their interpretation, to help in the planning of experiments, to predict their outcome and to test damage models. In the last years, powerful multipurpose particle-scattering framework based on the Monte-Carlo simulation (MCS) method, such as Geant4 and Geant4-DNA, were extended by user friendly interfaces such as TOPAS and TOPAS-nBio. This shifts their applicability from the realm of dedicated specialists to a broader range of scientists. In the present review we aim to give an overview over MCS based approaches to understand radiation interaction on a broad scale, ranging from cancerous tissue, cells and their organelles including the nucleus, mitochondria and membranes, over radiosensitizer such as metallic nanoparticles, and water with additional radical scavenger, down to isolated biomolecules in the form of DNA, RNA, proteins and DNA-protein complexes. Hereby the degradation of biomolecules by direct damage from inelastic scattering processes during the physical stage, and the indirect damage caused by radicals during the chemical stage as well as some parts of the early biological response is covered. Due to their high abundance the action of hydroxyl radicals (•OH) and secondary low energy electrons (LEE) as well as prehydrated electrons are covered in additional detail. Applications in the prediction of DNA damage, DNA repair processes, cell survival and apoptosis, influence of radiosensitizer on the dose distribution within cells and their organelles, the study of linear energy transfer (LET), the relative biological effectiveness (RBE), ion beam cancer therapy, microbeam radiation therapy (MRT), the FLASH effect, and the radiation induced bystander effect are reviewed. KW - DNA KW - Protein KW - G5P KW - OH KW - Au KW - AuNP KW - Radiation KW - SSB KW - DSB KW - Beta decay KW - Brachytherapy KW - Cancer treatment KW - Clustered nanoparticles KW - DNA damage KW - Dosimetry KW - Energy deposit KW - Geant4 KW - Geant4-DNA KW - Gold Nanoparticles KW - Livermore model KW - Low energy electrons KW - MCS KW - Microdosimetry KW - Monte-Carlo simulation KW - NP KW - OH radical KW - Particle scattering KW - Penelope model KW - Proteins KW - Radiation damage KW - Radiation therapy KW - Radiationtherapy KW - Radioactive decay KW - Radiolysis KW - Radiotherapy KW - Simulation KW - TOPAS KW - TOPAS-nbio KW - Base damage KW - Base loss KW - DNA radiation damage KW - Direct damage KW - Dissociative electron attachment (DEA) KW - Dissociative electron transfer (DET) KW - Double-strand break (DSB) KW - ESCA KW - Hydrated DNA KW - Hydrated electron KW - Hydration shell KW - Hydroxyl radical KW - Indirect damage KW - Ionization KW - Ionisation KW - NAP-XPS KW - Near ambient pressure xray photo electron spectroscopy KW - Net-ionization reaction KW - Prehydrated electron KW - Presolvated electron KW - Quasi-direct damage KW - ROS KW - Radical KW - Reactive oxygen species KW - Single-strand break (SSB) KW - XPS KW - Xray KW - Xray photo electron spectrocopy KW - Cosolute KW - Ectoin KW - Ectoine KW - GVP KW - Gene five protein KW - Hydroxyectoine KW - Ionizing radiation damage KW - OH radical scavenger KW - Monte-Carlo simulations KW - Nanodosimetry KW - Osmolyte KW - Particle scattering simulations KW - Protein unfolding KW - Radical Scavenge KW - Radical scavenger KW - Single-stranded DNA-binding proteins KW - SAXS KW - Bio-SAXS KW - X-ray scattering KW - ssDNA KW - dsDNA KW - FLASH effect KW - Bystander effect KW - Ion beam therapy KW - Bragg peak KW - LET KW - MCNP KW - Photons KW - Electrons KW - Carbon ions KW - MRT KW - RNA KW - RBE KW - base loss KW - abasic side KW - DMSO KW - Cells PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573240 DO - https://doi.org/10.1088/2399-6528/accb3f SN - 2399-6528 VL - 7 IS - 4 SP - 042001 PB - Institute of Physics (IOP) Publishing CY - London AN - OPUS4-57324 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hachenberger, Y. U. A1 - Rosenkranz, Daniel A1 - Kromer, C. A1 - Krause, B. C. A1 - Dreiack, N. A1 - Kriegel, F. L. A1 - Kozmenko, E. A1 - Jungnickel, H. A1 - Tentschert, J. A1 - Bierkandt, F. S. A1 - Laux, P. A1 - Panne, Ulrich A1 - Luch, A. T1 - Nanomaterial Characterization in Complex Media - Guidance and Application N2 - A broad range of inorganic nanoparticles (NPs) and their dissolved ions possess a possible toxicological risk for human health and the environment. Reliable and robust measurements of dissolution effects may be influenced by the sample matrix, which challenges the analytical method of choice. In this study, CuO NPs were investigated in several dissolution experiments. Two analytical techniques (dynamic light scattering (DLS) and inductively-coupled plasma mass spectrometry (ICP-MS)) were used to characterize NPs (size distribution curves) time-dependently in different complex matrices (e.g., artificial lung lining fluids and cell culture media). The advantages and challenges of each analytical approach are evaluated and discussed. Additionally, a direct-injection single particle (DI sp)ICP-MS technique for assessing the size distribution curve of the dissolved particles was developed and evaluated. The DI technique provides a sensitive response even at low concentrations without any dilution of the complex sample matrix. These experiments were further enhanced with an automated data evaluation procedure to objectively distinguish between ionic and NP events. With this approach, a fast and reproducible determination of inorganic NPs and ionic backgrounds can be achieved. This study can serve as guidance when choosing the optimal analytical method for NP characterization and for the determination of the origin of an adverse effect in NP toxicity. KW - Nanon KW - Characterization KW - SpICP-MS KW - Matrix KW - Dissolution PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572138 DO - https://doi.org/10.3390/nano13050922 VL - 13 IS - 5 SP - 1 EP - 19 AN - OPUS4-57213 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tscheuschner, Georg A1 - Ponader, Marco A1 - Raab, Christopher A1 - Weider, Prisca S. A1 - Hartfiel, Reni A1 - Kaufmann, Jan Ole A1 - Völzke, Jule L. A1 - Bosc-Bierne, Gaby A1 - Prinz, Carsten A1 - Schwaar, T. A1 - Andrle, Paul A1 - Bäßler, Henriette A1 - Nguyen, Khoa A1 - Zhu, Y. A1 - Mey, A. S. J. S. A1 - Mostafa, A. A1 - Bald, I. A1 - Weller, Michael G. T1 - Efficient Purification of Cowpea Chlorotic Mottle Virus by a Novel Peptide Aptamer N2 - The cowpea chlorotic mottle virus (CCMV) is a plant virus explored as a nanotechnological platform. The robust self-assembly mechanism of its capsid protein allows for drug encapsulation and targeted delivery. Additionally, the capsid nanoparticle can be used as a programmable platform to display different molecular moieties. In view of future applications, efficient production and purification of plant viruses are key steps. In established protocols, the need for ultracentrifugation is a significant limitation due to cost, difficult scalability, and safety issues. In addition, the purity of the final virus isolate often remains unclear. Here, an advanced protocol for the purification of the CCMV from infected plant tissue was developed, focusing on efficiency, economy, and final purity. The protocol involves precipitation with PEG 8000, followed by affinity extraction using a novel peptide aptamer. The efficiency of the protocol was validated using size exclusion chromatography, MALDI-TOF mass spectrometry, reversed-phase HPLC, and sandwich immunoassay. Furthermore, it was demonstrated that the final eluate of the affinity column is of exceptional purity (98.4%) determined by HPLC and detection at 220 nm. The scale-up of our proposed method seems to be straightforward, which opens the way to the large-scale production of such nanomaterials. This highly improved protocol may facilitate the use and implementation of plant viruses as nanotechnological platforms for in vitro and in vivo applications. N2 - Das Cowpea Chlorotic Mottle Virus (CCMV) ist ein Pflanzenvirus, das als nanotechnologische Plattform erforscht wird. Der robuste Selbstorganisationsmechanismus seines Kapsidproteins ermöglicht die Verkapselung und gezielte Abgabe von Medikamenten. Darüber hinaus kann das Kapsid-Nanopartikel als programmierbare Plattform für die Präsentation verschiedener molekularer Komponenten verwendet werden. Im Hinblick auf künftige Anwendungen ist eine effiziente Produktion und Reinigung von Pflanzenviren von entscheidender Bedeutung. In etablierten Protokollen stellt die notwendige Ultrazentrifugation aufgrund von Kosten, schwieriger Skalierbarkeit und Sicherheitsaspekten eine erhebliche Einschränkung dar. Darüber hinaus bleibt die Reinheit des endgültigen Virusisolats oft unklar. Hier wurde ein fortschrittliches Protokoll für die Reinigung von CCMV aus infiziertem Pflanzengewebe entwickelt, wobei der Schwerpunkt auf Effizienz, Wirtschaftlichkeit und Reinheit lag. Das Protokoll beinhaltet eine Fällung mit Polyethylenglycol (PEG 8000), gefolgt von einer Affinitätsextraktion mit einem neuartigen Peptid-Aptamer. Die Effizienz des Protokolls wurde mithilfe von Größenausschluss-Chromatographie (SEC), MALDI-TOF-Massenspektrometrie, Umkehrphasen-HPLC und Sandwich-Immunoassay validiert. Darüber hinaus wurde nachgewiesen, dass das endgültige Eluat der Affinitätssäule eine außergewöhnliche Reinheit (98,4 %) aufweist, die durch HPLC und Detektion bei 220 nm bestimmt wurde. Die Skalierung der von uns vorgeschlagenen Methode scheint einfach zu sein, was den Weg für eine größer angelegte Produktion solcher Nanomaterialien ebnet. Dieses stark verbesserte Protokoll könnte die Verwendung und Umsetzung von Pflanzenviren als nanotechnologische Plattformen für In-vitro- und In-vivo-Anwendungen erleichtern. KW - Affinity chromatography KW - Nanoparticles KW - Nanoscience KW - Carrier protein KW - Encapsulation KW - Combinatorial peptide library KW - Peptide binder KW - Vigna unguiculata KW - Augenbohne KW - Schlangenbohne KW - Pflanzenvirus KW - Plant virus KW - Upscaling KW - Commercialization KW - Reference material KW - Nanocarrier PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572645 DO - https://doi.org/10.3390/v15030697 VL - 15 IS - 3 SP - 1 EP - 24 PB - MDPI CY - Basel, Schweiz AN - OPUS4-57264 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR 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 - Hydrolysis of protein samples into amino acids facilitates the use of NMR spectroscopy for protein and peptide quantification. Different conditions have been tested for quantifying aromatic amino acids and proteins. The pH-dependent signal shifts in the aromatic region of amino acid samples were examined. A pH of 12 was found to minimize signal overlap of the four aromatic amino acids. Several aromatic compounds, such as terephthalic acid, sulfoisophthalic acid, and benzene tricarboxylic acid, were applied as internal standards. The quantification of amino acids from an amino acid standard 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 - Aromatic amino acid analysis KW - AAA KW - AAAA KW - Protein hydrolysis KW - Hydrochloric acid KW - Metrology KW - Traceability KW - NIST KW - Reference materials KW - Internal standard KW - Calibration KW - Compound-independent calibration KW - Histidine KW - Tyrosine KW - Tryptophan KW - Phenylalanine KW - Terephthalic acid KW - Benzene-1,3,5-tricarboxylic acid KW - Bovine serum albumin (BSA) KW - Quantitative protein analysis KW - Phenylketonuria PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570943 DO - https://doi.org/10.3390/mps6010011 VL - 6 IS - 1 SP - 1 EP - 13 PB - MDPI CY - Basel, Schweiz AN - OPUS4-57094 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knigge, Xenia A1 - Radnik, Jörg T1 - 1,3-Dimethyl-imidazolium dimethyl phosphate ([MMIM]+[DMP]−) analyzed by XPS and HAXPES N2 - The ionic liquid 1,3-dimethyl-imidazolium-dimethylphosphate ([MMIM]+[DMP]−) was analyzed using (hard) x-ray photoelectron spectroscopy. Here, XPS and HAXPES spectra are shown in comparison. For the acquisition of the XPS spectra, monochromatic Al Kα radiation at 1486.6 eV was used, while for the acquisition of the HAXPES spectra, monochromatic Cr Kα radiation at 5414.8 eV was applied. Here, survey scans and high-resolution spectra of P 2p, P 2s, C 1s, O 1s, and N 1s for both methods and P 1s, P KL2,3L2,3, and P KL1L2,3 for HAXPES are shown. KW - C7H15N2O4P KW - [MMIM]+[DMP]− KW - Lonic liquid KW - Hard x-ray photoelectron spectroscopy KW - HAXPES KW - XPS PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571604 DO - https://doi.org/10.1116/6.0002297 VL - 30 IS - 1 SP - 1 EP - 20 PB - AIP Publishing AN - OPUS4-57160 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schutter, Jan David A1 - Eberhardt, Karl A1 - Elert, Anna Maria A1 - Radnik, Jörg A1 - Geißler, Daniel A1 - Özcan Sandikcioglu, Özlem T1 - Synthesis and characterization of lipopolysaccharide (LPS) anchored polystyrene microparticles as a synthetic model system for attachment studies N2 - Outer membrane lipopolysaccharides (LPS) play a crucial role in determining attachment behavior and pathogenicity of bacteria. The aim of this study was to develop a simple procedure for anchoring bacterial lipopolysaccharides to polystyrene (PS) microparticles as a model system for in situ attachment studies. By using a swellcapture methodology, commercially available LPS of Pseudomonas aeruginosa (strain ATCC 27316 serotype 10.22) was anchored onto PS microparticles in a proof-of-concept study. A detailed chemical and morphological characterization has proven the success of LPS incorporation. It was shown that the coverage and structure of the LPS film was concentration dependent. The procedure can easily be adapted to LPS of other bacterial strains to generate a synthetic model toolkit for attachment studies. KW - Bacterial lipopolysaccharides KW - Pseudomonas aeruginosa KW - Polystyrene microparticles KW - Swell-capture KW - Biomimicry PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-579818 DO - https://doi.org/10.1016/j.colsurfb.2023.113301 SN - 0927-7765 VL - 226 SP - 1 EP - 7 PB - Elsevier B.V. AN - OPUS4-57981 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hallier, Dorothea C. A1 - Smales, Glen Jacob A1 - Seitz, H. A1 - Hahn, Marc Benjamin T1 - Bio-SAXS of single-stranded DNA-binding proteins: Radiation protection by the compatible solute ectoine N2 - Small-angle X-ray scattering (SAXS) can be used for structural determination of biological macromolecules and polymers in their native states (e.g. liquid phase). This means that the structural changes of (bio-)polymers, such as proteins and DNA, can be monitored in situ to understand their sensitivity to changes in chemical environments. In an attempt to improve the reliability of such experiments, the reduction of radiation damage occurring from exposure to X-rays is required. One such method, is to use scavenger molecules to protect macromolecules against radicals produced during radiation exposure, such as reactive oxygen species (ROS). In this study we investigate the feasibility of applying the compatible solute, osmolyte and radiation protector Ectoine (THP(B)), as a scavenger molecule during SAXS measurements of the single-stranded DNA-binding protein Gene-V Protein (G5P/GVP). In this case, we monitor the radiation induced changes of G5P during bio-SAXS measurments and the resulting microscopic energy-damage relation was determined from microdosimetric calculations by Monte-Carlo based particle scattering simulations with TOPAS/Geant4 and a custom target-model. This resulted in a median-lethal energy deposit of pure G5P at 4 mg mL−1 of E1/2 = 7 ± 5 eV, whereas a threefold increase of energy-deposit was needed under the presence of Ectoine to reach the same level of damage. This indicates that Ectoine increases the possible exposure time before radiation-damage to G5P is observed. Furthermore, the dominant type of damage shifted from aggregation in pure solutions towards a fragmentation for solutions containing Ectoine as a cosolute. These results are interpreted in terms of indirect radiation damage by reactive secondary species, as well as post-irradiation effects, related to preferential-exclusion of the cosolute from the protein surface. Hence, Ectoine is shown to provide a non-disturbing way to improve structure-determination of proteins via bio-SAXS in future studies. KW - BioSAXS KW - Bio-SAXS KW - Cosolute KW - Ectoine KW - G5P KW - GVP KW - Radiation damage KW - Radical Scavenger KW - Single-stranded DNA-binding proteins KW - X-ray scattering KW - DNA KW - ssDNA KW - Protein KW - SAXS KW - Small-angle xray scattering KW - McSAS3 KW - Dosimetry KW - Microdosimetry KW - Geant4 KW - Geant4-DNA KW - Topas KW - Topas-MC KW - Monte-Carlo simulations KW - Particle scattering simulations KW - Topas-nBio KW - OH Radical KW - OH radical scavenger KW - LEE KW - Ionizing radiation damage KW - Protein unfolding KW - Ectoin PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568909 DO - https://doi.org/10.1039/d2cp05053f SN - 1463-9076 SN - 1463-9084 VL - 25 IS - 7 SP - 5372 EP - 5382 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-56890 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tavasolyzadeh, Zeynab A1 - Tang, Peng A1 - Hahn, Marc Benjamin A1 - Hweidi, Gada A1 - Nordholt, Niclas A1 - Haag, Rainer A1 - Sturm, Heinz A1 - Topolniak, Ievgeniia T1 - 2D and 3D Micropatterning of Mussel‐Inspired Functional Materials by Direct Laser Writing N2 - AbstractThis work addresses the critical need for multifunctional materials and substrate‐independent high‐precision surface modification techniques that are essential for advancing microdevices and sensing elements. To overcome existing limitations, the versatility of mussel‐inspired materials (MIMs) is combined with state‐of‐the‐art multiphoton direct laser writing (DLW) microfabrication. In this way, 2D and 3D MIM microstructures of complex designs are demonstrated with sub‐micron to micron resolution and extensive post‐functionalization capabilities. This study includes polydopamine (PDA), mussel‐inspired linear, and dendritic polyglycerols (MI‐lPG and MI‐dPG), allowing their direct microstructure on the substrate of choice with the option to tailor the patterned topography and morphology in a controllable manner. The functionality potential of MIMs is demonstrated by successfully immobilizing and detecting single‐stranded DNA on MIM micropattern and nanoarray surfaces. In addition, easy modification of MIM microstructure with silver nanoparticles without the need of any reducing agent is shown. The methodology developed here enables the integration of MIMs in advanced applications where precise surface functionalization is essential. KW - Direct laser writing KW - Mussel-inspired materials KW - Polyglycerol KW - Polydopamine KW - Micropatterning PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-588778 DO - https://doi.org/10.1002/smll.202309394 SN - 1613-6829 SP - 1 EP - 12 PB - Wiley-VCH CY - Weinheim AN - OPUS4-58877 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Page, T.M. A1 - Nie, C. A1 - Neander, L. A1 - Povolotsky, T.L. A1 - Sahoo, A.K. A1 - Nickl, Philip A1 - Adler, J.M. A1 - Bawadkji, O. A1 - Radnik, Jörg A1 - Achazi, K. A1 - Ludwig, K. A1 - Lauster, D. A1 - Netz, R.R. A1 - Trimpert, J. A1 - Kaufer, B. A1 - Haag, R. A1 - Donskyi, Ievgen T1 - Functionalized Fullerene for Inhibition of SARS-CoV-2 Variants N2 - As virus outbreaks continue to pose a challenge, a nonspecific viral inhibitor can provide significant benefits, especially against respiratory viruses. Polyglycerol sulfates recently emerge as promising agents that mediate interactions between cells and viruses through electrostatics, leading to virus inhibition. Similarly, hydrophobic C60 fullerene can prevent virus infection via interactions with hydrophobic cavities of surface proteins. Here, two strategies are combined to inhibit infection of SARS-CoV-2 variants in vitro. Effective inhibitory concentrations in the millimolar range highlight the significance of bare fullerene’s hydrophobic moiety and electrostatic interactions of polysulfates with surface proteins of SARS-CoV-2. Furthermore, microscale thermophoresis measurements support that fullerene linear polyglycerol sulfates interact with the SARS-CoV-2 virus via its spike protein, and highlight importance of electrostatic interactions within it. All-atom molecular dynamics simulations reveal that the fullerene binding site is situated close to the receptor binding domain, within 4 nm of polyglycerol sulfate binding sites, feasibly allowing both portions of the material to interact simultaneously. KW - Covalent functionalization KW - Fullerene KW - SARS-CoV 2 KW - Sulfated materials KW - Virus inhibition PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568672 DO - https://doi.org/10.1002/smll.202206154 SN - 1613-6810 SP - 1 EP - 8 PB - Wiley VCH AN - OPUS4-56867 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fritzsche, Sven A1 - Pauw, Brian Richard A1 - Weimann, Christiane A1 - Sturm, Heinz T1 - First of its kind: a test artifact for direct laser writing N2 - With femtosecond-laser direct writing (fs-LDW) maturing in all aspects as a manufacturing technology, a toolset for quality assurance must be developed. In this work we introduce a first of its kind test artifact. Test artifacts are standardized 3D models with specific geometric features to evaluate the performance of writing parameters. Test artifacts are already common in other 3D additive manufacturing technologies e.g. selective laser melting. The test artifact introduced in this work was developed in particular to accommodate the high geometrical resolution of fs-LDW structures and the limited possibilities to examine the resulting structure. Geometric accuracy, surface adhesion as well as confocal Raman spectroscopy results were considered when evaluating the design of the test artifact. We will explain the individual features and design considerations of our fs-LDW test artifact. The difference between two slicers, Cura and 3DPoli, and the implications on measured feature sizes and the general shape is quantified. The measured geometries are used to derive a general design guide for a specific combination of photoresists, laser power and scanning speed and to analyze the geometric accuracy of a structure produced using these guidelines. The shown test artifact is publicly available as STL file on GitHub (https://github.com/BAMresearch/2PP-TestArtifact) and in the supplement. KW - Laser direct writing KW - Multi photon lithography KW - Reference material KW - Raman spectroscopy KW - Confocal raman imaging KW - Slicers KW - Open data on zenodo PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-580951 DO - https://doi.org/10.1088/1361-6501/acc47a VL - 34 IS - 7 SP - 1 EP - 14 PB - IOP Science AN - OPUS4-58095 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A. L. A1 - Silbernagl, Dorothee A1 - Yasuda, N. A1 - Feiler, Torvid A1 - Sturm, Heinz A1 - Emmerling, Franziska T1 - An atomistic mechanism for elasto-plastic bending in molecular crystals N2 - Mechanically flexible single crystals of molecular materials offer potential for a multitude of new directions in advanced materials design. Before the full potential of such materials can be exploited, insight into their mechanisms of action must be better understood. Such insight can be only obtained through synergistic use of advanced experimentation and simulation. We herein report the first detailed mechanistic study of elasto-plastic flexibility in a molecular solid. An atomistic origin for this mechanical behaviour is proposed through a combination of atomic force microscopy, μ-focus synchrotron X-ray diffraction, Raman spectroscopy, ab initio simulation, and computed elastic tensors. Our findings suggest that elastic and plastic bending are intimately linked and result from extensions of the same molecular deformations. The proposed mechanism bridges the gap between contested mechanisms, suggesting its applicability as a general mechanism for elastic and plastic bending in organic molecular crystals. KW - Mechanical property KW - Mechanical flexibility KW - Organic crystal PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-577722 DO - https://doi.org/10.1039/D2SC06470G SN - 2041-6520 VL - 14 IS - 13 SP - 3441 EP - 3450 PB - Royal Society of Chemisty (RSC) CY - London/Cambridge AN - OPUS4-57772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hildebrandt, R. A1 - Seifert, M. A1 - George, Janine A1 - Blaurock, S. A1 - Botti, S. A1 - Krautscheid, H. A1 - Grundmann, M. A1 - Sturm, C. T1 - Determination of acoustic phonon anharmonicities via second-order Raman scattering in CuI N2 - We demonstrate the determination of anharmonic acoustic phonon properties via second-order Raman scattering exemplarily on copper iodide single crystals. The origin of multi-phonon features from the second-order Raman spectra was assigned by the support of the calculated 2-phonon density of states. In this way, the temperature dependence of acoustic phonons was determined down to 10 K. To determine independently the harmonic contributions of respective acoustic phonons, density functional theory in quasi-harmonic approximation was used. Finally, the anharmonic contributions were determined. The results are in agreement with earlier publications and extend CuI’s determined acoustic phonon properties to lower temperatures with higher accuracy. This approach demonstrates that it is possible to characterize the acoustic anharmonicities via Raman scattering down to zero-temperature renormalization constants of at least 0.1 cm⁻¹. KW - Thermoelectrics KW - Thermal transport KW - Phonon interactions KW - Density functional theory KW - Phonons PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593164 DO - https://doi.org/10.1088/1367-2630/ad1141 SN - 1367-2630 VL - 25 IS - 12 SP - 1 EP - 12 PB - IOP Publishing CY - London AN - OPUS4-59316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -