TY - JOUR
A1 - Nicolai, Marcel
A1 - Bulling, Jannis
A1 - Narayanan, M.M.
A1 - Zeipert, Henning
A1 - Prager, Jens
A1 - Henning, Bernd
T1 - Dynamic interface behavior in coupled plates: Investigating Lamb wave mode repulsion with a spring-based model
N2 - This study investigates the phenomenon of mode repulsion in Lamb waves propagating through two coupled plates with an elastic interface. Using a spring-based coupling model and the Scaled Boundary Finite Element Method, the dispersion curves of the coupled system are analyzed under various interface conditions—weak coupling, sliding boundary, and perfect coupling. This research highlights how the mechanical stiffness of the interface influences the separation of modes and the emergence of repulsion regions. A novel focus on interface displacements reveals a unique dynamic behavior within the repulsion regions, driven by in-phase and out-of-phase oscillations of the coupled plates. The findings provide a physically grounded explanation of mode repulsion, linking it to the strain patterns in the interface. This insight lays the theoretical groundwork for future applications in material characterization and non-destructive evaluation, enabling more precise selection of Lamb wave modes for scientific and industrial purposes.
KW - Lamb waves
KW - Mode repulsion
KW - Coupled plates
KW - Elastic interface
KW - Dispersion curves
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-642245
DO - https://doi.org/10.1016/j.ultras.2025.107799
SN - 0041-624X
VL - 158
SP - 1
EP - 9
PB - Elsevier BV
AN - OPUS4-64224
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scholl, Juliane
A1 - Lisec, Jan
A1 - Bagheri, Abbas
A1 - Meiers, Emelie
A1 - Russo, Francesco Friedrich
A1 - Haase, Hajo
A1 - Koch, Matthias
T1 - Unveiling aging mechanisms of electrolytes in commercial end-of-life lithium-ion batteries
N2 - In this study, 77 end-of-life (EOL) commercial lithium-ion batteries (LIBs) of various formats were systematically analyzed to investigate electrolyte degradation and the influence of pristine electrolyte compositions on aging behavior. Comprehensive chemical characterization was conducted using targeted and non-targeted mass spectrometry (MS), employing LC-MS/MS, GC-MS, and high-resolution MS (HRMS). This integrated approach enabled the identification of confirmed pristine components and complex degradation products. The results show that rechargeable pouch and cylindrical cells often deviate from conventional model systems, containing mixed lithium salt anions, ionic liquids (ILs), and high concentrations of triflates, triflimides, and bis(fluorosulfonyl)imide (FSI). These function as solvents, salts, or safety-enhancing additives. Specific IL degradation products were identified, and hypotheses formulated on previously unreported pathways. Furthermore, a novel series of oligomerization products of propylene carbonate (PC) was detected. In contrast, non-rechargeable coin cells revealed widespread use of per- and polyfluoroalkyl substances (PFAS) in their original electrolytes. Based on ex situ analyses, hypothetical PFAS degradation mechanisms are proposed here for the first time. The absence of carbonate oligomers and lithium salt-derived products, alongside the presence of standard carbonates, indicates lithium counterion coordination as a key factor in Lewis acid-catalyzed degradation. This study offers valuable insights into real-world battery aging.
KW - Transformation products
KW - Lithium-ion batteries
KW - Fluorinated Compounds
KW - Gas chromatography/ QTOF-MS
KW - HILIC-LC-MS/MS
KW - PFAS
KW - Electrochemistry
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644991
DO - https://doi.org/10.1016/j.jpowsour.2025.238613
SN - 0378-7753
VL - 661
SP - 1
EP - 10
PB - Elsevier B.V.
AN - OPUS4-64499
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wang, Kun
A1 - Schukar, Marcus
A1 - Hicke, Konstantin
A1 - Lu, Xin
T1 - Effect of humidity on fiber-optic temperature sensing
N2 - This study investigates the influence of ambient humidity on the temperature sensitivity, measurement accuracy, and uncertainty of optical fibers with different coatings, using a Rayleigh-based distributed sensing technique. Polymer-coated fibers (acrylate and polyimide) and metal-coated fibers (copper and gold) were tested under controlled humidity (30%–90% RH) and temperature (20–60 °C) conditions. Rayleigh-based measurements revealed a slight but consistent decrease in temperature sensitivity with increasing humidity for all polymer-coated fibers, attributed to humidity-induced changes in coating stiffness and strain transfer. In contrast, metal-coated fibers exhibited humidity-independent behavior and superior stability. These findings highlight the non-negligible role of ambient humidity in fiber-optic temperature sensing, particularly in Rayleigh-based systems using hygroscopic coatings. The results provide practical guidance for fiber and coating selection in humid environments and offer broader insight into humidity–strain–temperature coupling mechanisms relevant to other fiber-optic sensing mechanisms.
KW - Distributed sensing
KW - Humidity effect
KW - Temperature sensing
KW - Optical fiber coatings
KW - Temperature uncertainty
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650040
DO - https://doi.org/10.1016/j.measurement.2025.119905
SN - 0263-2241
VL - 261
SP - 1
EP - 9
PB - Elsevier Ltd.
AN - OPUS4-65004
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Tim
A1 - Huber, Norbert
T1 - Microstructure and orientation effects on microcompression-induced plasticity in nanoporous gold
N2 - Understanding the plastic deformation of nanoporous metals requires a detailed examination of their small-scale microstructural features. In this work, we present a computational study of micropillar compression in single crystal nanoporous gold (NPG) using crystal plasticity. This approach enables a systematic investigation of three key microstructural effects, including ligament size (50 ≤ 𝑙 ≤ 400 nm), solid fraction (0.2 ≤ 𝜑 ≤ 0.3), and initial crystal orientation ([001] and [111] ̄ ), on the plastic response far beyond yielding. After validation against experimental data, the study reveals that, in line with the ’smaller is stronger’ trend, besides the yield strength, the strain hardening rate also increases as ligament size decreases. Moreover, the strain hardening rate follows a power-law scaling with solid fraction, similar to the yield strength. The analysis of two distinct crystal orientations presents findings contrasting with previous assumptions. While the yielding onset remains orientation-independent, as expected, an increase in the strain hardening rate emerges for the harder [11-1] orientation with continued compression. An effect that becomes more pronounced with increasing solid fraction and decreasing ligament size. Under these conditions, harder orientations also amplify local stress heterogeneity. Notably, the stress distribution in NPG is nearly twice as wide as that observed in the single crystal bulk material (𝜑 = 1.0). Compared to the crystal plasticity approach, traditional isotropic plasticity predicts more uniform local stress fields.
KW - Nanoporous gold
KW - Microcompression
KW - Plasticity
KW - Size effect
KW - Micromechanics
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650137
DO - https://doi.org/10.1016/j.actamat.2025.121798
SN - 1359-6454
VL - 304
SP - 1
EP - 13
PB - Elsevier Inc.
AN - OPUS4-65013
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Durlo Tambara, Luís Urbano
A1 - Nikoonasab, Ali
A1 - Radtke, Martin
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Gluth, Gregor
T1 - Determination of the oxidation depths of ground granulated blast furnace slag-containing cement pastes using Mn K-edge X-ray absorption near-edge structure spectroscopy
N2 - The redox potential of the pore solution of hardened cements containing ground granulated blast furnace slag (GGBFS) affects reinforcement corrosion and immobilization of radioactive waste. Here, Mn K-edge X-ray absorption near-edge structure (XANES) spectroscopy was applied to determine the depth profile of the oxidation state of manganese in hardened GGBFS-containing cement pastes. Manganese was oxidized in the outer regions of some of the pastes, but the depth to which this occurred was not identical with the ‘blue-green/white color change front’, usually interpreted as indicating oxidation of sulfur species. For CEM III/B, the color change of the material was gradual and thus unsuitable for a precise determination of the oxidation depth, while for the alkali-activated slag, a distinct color change front was found, but full oxidation of manganese and sulfur had not occurred in the brighter region. Mn K-edge XANES spectroscopy is thus a more reliable method than the determination of the visual color change front to follow the ingress of the oxidation front.
KW - Manganese
KW - Oxidation
KW - Sulfide
KW - Alkali-activated materials
KW - Redox conditions
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-651469
DO - https://doi.org/10.1111/jace.70445
SN - 0002-7820
SN - 1551-2916
VL - 109
IS - 1
SP - 1
EP - 11
PB - Wiley
CY - Oxford
AN - OPUS4-65146
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Campari, Alessandro
A1 - Konert, Florian
A1 - Razavi, Nima
A1 - Sobol, Oded
A1 - Alvaro, Antonio
T1 - Hydrogen-assisted cracking: A deep learning approach for fractographic analysis
N2 - Hydrogen handling equipment suffers from interaction with their operating environment, which degrades the mechanical properties and compromises component integrity. Hydrogen-assisted cracking is responsible for several industrial failures with potentially severe consequences. A thorough failure analysis can determine the failure mechanism, locate its origin, and identify possible root causes to avoid similar events in the future. Postmortem fractographic analysis can classify the fracture mode and determine whether the hydrogen-metal interaction contributed to the component’s breakdown. Experts in fracture classification identify characteristic marks and textural features by visual inspection to determine the failure mechanism. Although widely adopted, this process is time-consuming and influenced by subjective judgment and individual expertise. This study aims to automate fractographic analysis through advanced computer vision techniques. Different materials were tested in hydrogen atmospheres and inert environments, and their fracture surfaces were analyzed by scanning electron microscopy to create an extensive image dataset. A pre-trained Convolutional Neural Network was finetuned to accurately classify brittle and ductile fractures. In addition, Grad-CAM interpretability method was adopted to identify the image regions most influential in the model’s prediction and compare the saliency maps with expert annotations. This approach offered a reliable data-driven alternative to conventional fractographic analysis.
KW - Failure analysis
KW - Fractographic analysis
KW - Hydrogen embrittlement
KW - Material compatibility
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-646610
DO - https://doi.org/10.1016/j.commatsci.2025.114366
SN - 0927-0256
VL - 262
SP - 1
EP - 16
PB - Elsevier Science
CY - Amsterdam [u.a.]
AN - OPUS4-64661
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Risse, Kerstin
A1 - Nikiforidis, Constantinos V.
A1 - Morris, Imogen
A1 - Thünemann, Andreas
A1 - Drusch, Stephan
T1 - Regulating the heat stability of protein-phospholipid stabilised oil-water emulsions by changing the phospholipid headgroup or fatty acyl chain
N2 - Stabilising oil–water emulsions remains a central challenge across food, pharmaceutical and cosmetic applications. β-lactoglobulin (β-LG) and phospholipids (PLs) can act synergistically at oil-water interfaces: PLs adsorb rapidly, while β-LG forms a viscoelastic protein network that enhances long-term stability. However, competitive adsorption between proteins and PLs can disrupt interfacial structure. In addition, for commercial production, emulsions are often exposed to heat treatment during or after manufacture, for instance due to food safety requirements. Yet, the combined effects of PL structure and heat treatment on interfacial organisation and emulsion stability remain poorly understood.
Here we show that PL saturation and processing temperature jointly determine interfacial organisation, protein-PL interactions and emulsion stability. Using β-LG-PL emulsions, we combined ζ-potential measurements, small-angle X-ray scattering (SAXS), micro-differential scanning calorimetry (μDSC), X-ray diffraction and confocal laser scanning microscopy (CLSM) to link interfacial composition with functional stability.
Below the β-LG denaturation temperature (≤75 °C), saturated PLs promoted partial unfolding of β-LG at the interface without displacement, producing mixed protein-PL networks with enhanced viscoelasticity and stability. Unsaturated PLs displaced β-LG, yielding less elastic interfaces and promoting protein aggregation in the bulk. At ≥75 °C, increased hydrophobicity intensified protein-protein interactions irrespective of PL type.
Our findings reveal that saturated PLs shift the β-LG denaturation temperature upward by restricting molecular mobility, without preventing quaternary-level protein-protein interactions. Thermal denaturation, regardless of PL type, promoted interfacial multilayer formation at 90 °C. These results provide a mechanistic framework for tailoring emulsion stability via lipid saturation and processing temperature.
KW - Small-angle X-ray scattering
KW - SAXS
KW - Nanostructure
KW - Reference Method
KW - Colloid
KW - Nanoparticle
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648956
DO - https://doi.org/10.1016/j.jcis.2025.139530
SN - 0021-9797
VL - 705
SP - 1
EP - 25
PB - Elsevier Inc.
AN - OPUS4-64895
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kozachynskyi, Volodymyr
A1 - Staubach, Dario
A1 - Esche, Erik
A1 - Biegler, Lorenz T.
A1 - Repke, Jens-Uwe
T1 - Parameter estimation in dynamic multiphase liquid–liquid equilibrium systems
N2 - Modeling dynamic systems with a variable number of liquid phases is a challenging task, especially in scenarios where the model is designed for optimization tasks such as parameter estimation. Although there exist methods to model the appearance and disappearance of liquid phases in dynamic systems, they usually require integer variables. In this work, the smoothed continuous approach (SCA) is developed for use with a large number of solvers, since it relies only on continuous variables. To demonstrate the applicability of the new method, the SCA is then applied to model the batch esterification of acetic acid with 1-propanol to water and propyl acetate, and to estimate the reaction parameters. Since the mixture may separate into two liquid phases during the course of the reaction, the parameters are estimated with information on the liquid compositions of both separated liquid phases, which improves the accuracy of the parameter estimates and opens new possibilities for optimal experimental design.
KW - Parameter Estimation
KW - Uncertainty
KW - Dynamic Modeling
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650059
DO - https://doi.org/10.1016/j.compchemeng.2025.109485
SN - 0098-1354
VL - 206
SP - 1
EP - 16
PB - Elsevier Ltd.
AN - OPUS4-65005
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mikhlin, Yuri
A1 - Muzikansky, Anya
A1 - Zysler, Melina
A1 - Thünemann, Andreas
A1 - Zitoun, David
T1 - Emerging electrochemistry of high-concentration colloids: Redox-activity, wide potential window and electrophoretic transport of iron oxide nanoparticles
N2 - High-concentration, steric stabilizer free colloids and particularly their electrochemical behavior remains almost unexplored. Herein, we report on the electrochemistry (cyclic voltammetry, impedance spectroscopy, etc.) of highly concentrated aqueous colloidal dispersion up to 800 g/L of citrate-capped ∼11 nm Fe3-xO4 nanoparticles (NPs) without background electrolyte on glassy carbon electrodes. X-ray photoelectron spectroscopy was applied to analyze the reaction products. Solid-state Fe(II)/Fe(III) conversion was concluded to determine the cathodic and anodic faradaic reactions of the particles, with the currents depending on approximately square root of the concentration. The electrochemical reactions are coupled with the electrophoretic transfer of the negatively charged NPs on toward the anode, with the ohmic-type behavior in the bulk demonstrated by the nearly linear voltametric cathodic curves and frequency-independent impedance above ∼10–100 Hz. Accumulation and clogging of the NPs retards diffusion near anode. Hydrogen and especially oxygen evolution are arrested, and very large oxidation overpotentials result in extraordinary wide, up to 12 V, electrochemical window of water stability. The findings shed light onto basic features of the electrochemistry of high-concentration colloids without added electrolyte and their potential applications in redox flow batteries, electrophoretic deposition and beyond.
KW - Nanoplastics
KW - SAXS
KW - Small-angle X-ray scattering
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644340
DO - https://doi.org/10.1016/j.jcis.2025.139247
SN - 0021-9797
VL - 703
SP - 1
EP - 18
PB - Elsevier Inc.
AN - OPUS4-64434
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ferrari, Bruno
A1 - Fantin, Andrea
A1 - Said, D.
A1 - Fitch, A. N.
A1 - Suárez Ocano, Patricia
A1 - Mishurova, Tatiana
A1 - Roveda, Ilaria
A1 - Kromm, Arne
A1 - Darvishi Kamachali, Reza
A1 - Bruno, Giovanni
A1 - Evans, Alexander
A1 - Requena, G.
A1 - Agudo Jácome, Leonardo
A1 - Serrano Munoz, Itziar
T1 - The impact of scanning strategy on cell structures in PBF-LB/M/IN718: an in situ synchrotron x-ray diffraction study
N2 - In additive manufacturing, any change of the process parameters, such as scanning strategy, directly affects the cooling rates, heat accumulation, and overall thermal history of the build. Consequently, parts built with different process parameters tend to have different levels of crystallographic texture, residual stress, and dislocation density. These features can influence the properties of the material and their development during post-processing operations. In this study, IN718 prisms were built by laser powder bed fusion (PBF-LB/M) using two different scanning strategies (continuous 67° rotations around the build direction, ROT, and alternating 0°/67° scans, ALT) to provide two different as-built conditions. In situ time-resolved synchrotron diffraction was performed during a solution heat treatment at 1027 °C for 1 h. Ex situ scanning electron microscopy was used to support and complement the in situ observations. An approach to quantify the effect of elemental microsegregation at the cell walls is developed based on the deconvolution of asymmetric γ-nickel matrix peaks. Following this approach, the scanning strategies are shown to affect the as-built fraction of cell walls in the material, resulting in a difference of approximately 5 %, in weight fraction, between ROT and ALT (19 % vs. 24 %, respectively). This microsegregation was observed to be rapidly homogenized during the heating ramp, and no significant changes to the peak shape in the γ peaks occurred during the isothermal part of the heat treatment, regardless of the scanning strategy.
KW - Additive manufacturing
KW - Inconel 718
KW - Synchrotron x-ray diffraction
KW - Heat treatment
KW - Laser powder bed fusion
KW - Cellular microstructure
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650958
DO - https://doi.org/10.1016/j.jmrt.2025.11.214
SN - 2238-7854
VL - 41
SP - 593
EP - 608
PB - Elsevier B.V.
AN - OPUS4-65095
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rossi, Andrea
A1 - Corrao, Elena
A1 - Alladio, Eugenio
A1 - Drobne, Damjana
A1 - Hodoroaba, Vasile-Dan
A1 - Jurkschat, Kerstin
A1 - Kononenko, Veno
A1 - Madbouly, Loay Akmal
A1 - Mrkwitschka, Paul
A1 - Yasamin, Nakhli
A1 - Novak, Sara
A1 - Radnik, Jörg
A1 - Saje, Špela
A1 - Santalucia, Rosangela
A1 - Sordello, Fabrizio
A1 - Pellegrino, Francesco
T1 - Multivariate optimization and characterization of graphene oxide via design of experiments and chemometric analysis
N2 - Controlling the structure and properties of graphene oxide (GO) remains a challenge due to the poor reproducibility of conventional synthetic protocols and limited understanding of parameter-property relationships. In this study, we present an integrated analytical framework that combines Design of Experiments (DoE) with chemometric modelling to systematically assess the effects of eight synthesis variables on GO’s physicochemical and functional features. A Plackett–Burman experimental design enabled efficient screening of synthesis conditions, while comprehensive characterization (spanning UV–Vis spectroscopy, XPS, SEM–EDX, TEM–EDX, and XRD) was coupled with multivariate tools (Principal Component Analysis and Multiple Linear Regression) to identify statistically significant correlations between synthetic inputs and material responses. Notably, we demonstrate that UV–Vis spectra can serve as a robust proxy for oxidation state, offering a rapid and accessible alternative to surface-sensitive methods. The approach yields a predictive analytical toolkit for guiding GO synthesis and highlights a generalizable strategy for the rational design of flat nanomaterials. This work supports reproducible, resource-efficient material development aligned with Safe and Sustainable by Design (SSbD) principles.
KW - Graphene oxide
KW - 2D-materials
KW - Design of Experiment
KW - Synthesis
KW - Chemometric analysis
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652576
DO - https://doi.org/10.1016/j.flatc.2025.100988
SN - 2452-2627
VL - 55
SP - 1
EP - 9
PB - Elsevier B.V.
AN - OPUS4-65257
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mantouvalou, I.
A1 - Bauer, L.J.
A1 - Truong, V.-B.
A1 - Wagener, Y.
A1 - Förste, F.
A1 - Maruchenko, O.
A1 - Werner, S.
A1 - Lizzi, F.
A1 - Wieder, Frank
A1 - Wolff, T.
A1 - Kanngießer, B.
A1 - Zaslansky, P.
T1 - Quantitative micro-XRF combined with X-ray imaging reveals correlations between Zn concentration and dentin tubule porosity across entire teeth
N2 - Bony materials are biogenic composites of protein fibers and mineral that create hierarchical structures. In the case of teeth, dentin is the main component and similar to other bones, it contains porosity at multiple length scales. It is traversed by micron-sized hollow channels known as dentinal tubules, essential for temperature and pain sensation. Tubule density and thus porosity vary throughout the macroscopic three-dimensional (3D) structure, with porosity increasing toward the pulp. The different densities in teeth are easily revealed non-destructively in 3D by X-ray imaging using computer tomography (CT). Yet elemental composition analysis is more difficult to obtain from within the centimeter-sized heterogeneous bulk material. We describe an approach of merging CT measurements of healthy, intact bovine teeth with micro-X-ray fluorescence (micro-XRF) images of matching serially sectioned slices. Through the combination of multi-resolution quantitative CT measurements with elemental mass fraction derivation, gradients in density and element distributions such as calcium (Ca), phosphorus (P), and zinc (Zn) are revealed across entire teeth in 3D. While the main constituents (Ca and P) are homogeneously distributed in the matrix, Zn concentration increases significantly and exponentially toward the pulp. We find an inverse association between dentin tissue density and Zn concentration localizing this element in or around tubules. Our data serve as a quantitative reference for density and Zn mass fractions in healthy, neither carious nor hypermineralized dentin, as a basis for comparisons across species in health and disease states.
KW - Dentin density
KW - Micro-computer tomography
KW - Quantitative micro-X-ray fluorescence
KW - Tubule porosity
KW - Zn distribution
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654215
DO - https://doi.org/10.1002/VIW.20250173
SN - 2688-3988
SN - 2688-268X
SP - 1
EP - 14
PB - Wiley Online Library
AN - OPUS4-65421
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Klippel, Andrea
A1 - Hofmann‐Böllinghaus, Anja
A1 - Piechnik, Kira
A1 - Heydick, Lukas
A1 - Wu, Hongyi
A1 - Köhler, Florian
A1 - Klaffke, Benjamin
T1 - Experimental Analysis of Fire Behavior in Pine Forests and Agricultural Fields: Large‐Scale Tests Conducted Within the European TREEADS Project
N2 - Two large‐scale experiments investigated fire spread mechanisms in vegetation ground fires in a pine forest and an agricultural field within the European TREEADS project. The tests, conducted in Saxony‐Anhalt and Brandenburg, targeted regions with dry, sandy soils and extensive pine stands and aim to improve suppression strategies and wildfire research. The forest experiment was conducted on a 16 × 22 m plot with line ignition using a gasoline‐diesel mix. Fire spread was documented with drone‐based video and infrared imaging. Ninety‐six thermocouples and two gas sensors were mounted on trees, and a mobile FTIR spectrometer enabled real‐time smoke analysis. A tilled and foam‐treated strip prevented uncontrolled spread. Under stable weather conditions (23°C, light wind, low soil moisture), a consistent temperature rise and distinct combustion phases were observed. Smoldering dominated in areas with mosses, grasses, and deadwood, with intermittent flaming, limited flame heights (< 0.5 m), and substantial smoke production. Peak temperatures exceeded 500°C, and CO concentrations reached 238 ppm, though wind turbulence complicated gas sampling. The second experiment on a cut agricultural field near Nauen involved burning approximately 700 m2 using a 20 m ignition line aligned with wind direction. Drone‐based infrared monitoring captured rapid spread on the stubble surface. The results underscore the variability and measurement challenges of outdoor fires and highlight the necessity of continued large‐scale experiments to support physical and numerical wildfire modeling. These findings provide essential empirical data for evaluating vegetation‐specific burning behavior, improving sensor deployment strategies, and refining validation approaches for next‐generation wildfire spread models under central European fuel and weather conditions, and supporting decision‐making in wildfire management.
KW - Wildfire
KW - Pine
KW - Crop
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654199
DO - https://doi.org/10.1002/fam.70045
SN - 0308-0501
SP - 1
EP - 11
PB - Wiley
AN - OPUS4-65419
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kanaris, Orestis
A1 - Sobisch, Lydia-Yasmin
A1 - Gödt, Annett
A1 - Schreiber, Frank
A1 - Nordholt, Niclas
T1 - Consequences of benzalkonium chloride tolerance for selection dynamics and de novo resistance evolution driven by antibiotics
N2 - Biocides are used in large amounts in industrial, medical, and domestic settings. Benzalkonium chloride (BAC) is a commonly used biocide, for which previous research revealed that Escherichia coli can rapidly adapt to tolerate BAC-disinfection, with consequences for antibiotic susceptibility. However, the consequences of BAC tolerance for selection dynamics and resistance evolution to antibiotics remain unknown. Here, we investigated the effect of BAC tolerance in E. coli on its response upon challenge with different antibiotics. Competition assays showed that subinhibitory concentrations of ciprofloxacin—but not ampicillin, colistin and gentamicin—select for the BAC-tolerant strain over the BAC-sensitive ancestor at a minimal selective concentration of 0.0013–0.0022 µg/mL. In contrast, the BAC-sensitive ancestor was more likely to evolve resistance to ciprofloxacin, colistin and gentamicin than the BAC-tolerant strain when adapted to higher concentrations of antibiotics in a serial transfer laboratory evolution experiment. The observed difference in the evolvability of resistance to ciprofloxacin was partly explained by an epistatic interaction between the mutations conferring BAC tolerance and a knockout mutation in ompF encoding for the outer membrane porin F. Taken together, these findings suggest that BAC tolerance can be stabilized in environments containing low concentrations of ciprofloxacin, while it also constrains evolutionary pathways towards antibiotic resistance.
KW - AMR
KW - Resistance evolution
KW - Resistance selection
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653842
DO - https://doi.org/10.1038/s44259-025-00170-8
SN - 2731-8745
VL - 4
IS - 1
SP - 1
EP - 13
PB - Springer Science and Business Media LLC
AN - OPUS4-65384
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schönsee, Eric
A1 - Hüsken, Götz
A1 - Kocherla, Amarteja
A1 - Strangfeld, Christoph
T1 - Influences of Surface Properties on the Reflection Intensity - Towards in Situ Monitoring During Early Age Hydration of CEM I
N2 - Interlayer bonding in 3D concrete printing is influenced by the hydration progress and surface moisture of the previously printed layer. For effective quality control, continuous in situ monitoring of interlayer surface properties is required. This study investigated reflection intensity as a method for in situ measurements during the hydration of CEM I mixtures with varying retarder contents. Additional factors influencing the reflection intensity are also examined. Two laser line scanners with different wavelengths were used to track hydration over 72 h. Vicat tests and isothermal calorimetry served as reference methods. Across all the mixtures, the reflection intensity exhibited a repeatable pattern with five different stages. A sharp increase in intensity during the third stage was consistent with the acceleration period of hydration. These findings suggest that reflection intensity measurements could serve as a promising tool for evaluating interlayer bonding in 3D concrete printing.
KW - In situ hydration monitoring
KW - Cement
KW - Optical methods
KW - Reflection intensity
KW - Additive manufacturing
KW - Isothermal calorimetry
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653430
DO - https://doi.org/10.1007/s10921-025-01326-2
SN - 1573-4862
VL - 45
IS - 1
SP - 1
EP - 17
PB - Springer Nature
AN - OPUS4-65343
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wagner, Jan
A1 - Häfner, P.
A1 - Reimann, H.-A.
A1 - Schartel, Bernhard
T1 - Valorization of Natural Fibers in Flame Retarded Poly(lactic acid)
N2 - Extensive research has explored natural fiber reinforced composites, typically focusing on a single fiber within a polymer matrix. Comprehensive comparisons across different natural fibers in the same polymer, which are critical for industrial material selection, remain limited. This work presents a systematic comparison of untreated hemp, flax, and sisal fibers incorporated at varying fiber lengths and loadings into flame retarded poly(lactic acid) (PLA). Fire behavior, thermal, and mechanical responses were investigated through thermogravimetry, UL 94, and cone calorimetry, alongside crystallinity, molecular weight (MW), and microstructural analysis. Fiber incorporation reduced the peak heat release rate (pHRR) by up to 30 % in 30 wt% hemp, attributed to protective layer formation, but increased flammability in UL 94. A phytic acid melamine salt combined with expandable graphite and 20 wt% hemp produced incomplete combustion at 50 kW/m², raising char residue from 4 to 24 wt% and halving pHRR. Petrella plots revealed that fiber addition alone lowered fire load and flashover propensity as effectively as phytic acid melamine; with hemp, phytic acid and expendable graphite, the flashover hazard and fire load were halved. MW was preserved while crystallinity and modulus increased with fiber content. Hemp delivered the most consistent reinforcement, while optimized processing enabled flax and sisal to improve stiffness. Performance gains were strongest when individual fibers were dispersed via optimized processing, preventing bundle fracture under load. Plasma modification of the fibers improved the maximum tensile strength in the composites. A practical guide is provided for valorizing natural fibers in PLA composites, demonstrating routes to bio-based, compostable materials with improved fire safety and mechanical performance suitable for industrial processing.
KW - Poly(lactic acid)
KW - Hemp
KW - Sisal
KW - Flax
KW - Flame retardant
KW - Phytic acid
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653038
DO - https://doi.org/10.1016/j.mtcomm.2025.114575
SN - 2352-4928
VL - 50
SP - 1
EP - 41
PB - Elsevier Ltd.
AN - OPUS4-65303
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cairns, Warren R. L.
A1 - Braysher, Emma C.
A1 - Butler, Owen T.
A1 - Cavoura, Olga
A1 - Davidson, Christine M.
A1 - Todoli Torro, Jose Luis
A1 - von der Au, Marcus
T1 - Atomic spectrometry update: review of advances in environmental analysis
N2 - This review covers advances in the analysis of air, water, plants, soils and geological materials by a range of atomic spectrometric techniques including atomic emission, absorption, fluorescence and mass spectrometry.
KW - Environmental analysis
KW - Review
KW - Trend Article
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653977
DO - https://doi.org/10.1039/D5JA90058A
SN - 0267-9477
VL - 41
IS - 1
SP - 16
EP - 70
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65397
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stolar, Tomislav
A1 - Alić, Jasna
A1 - Casali, Lucia
A1 - Gugin, Nikita
A1 - Baláž, Matej
A1 - Michalchuk, Adam A.L.
A1 - Emmerling, Franziska
ED - Stolar, Tomislav
T1 - Mechanochemistry: Looking back and ahead
N2 - Starting with the discovery of fire and the preparation of food in prehistoric times, mechanochemistry is the oldest form of chemistry that humans have controlled. Mechanochemical practices, such as grinding with a mortar and pestle, continued into the Middle Ages until dedicated scientific studies began in the 19th century. Since then,research in mechanochemistry has shown that many chemicalreactions can be performed via mechanical force without or with small amounts of solvent. Besides being time, material, and energy efficient, mechanochemical reactions often yield products that differ from those obtained in solution. Therefore, not only is mechanochemistry greener and more sustainable than conventional solution chemistry, but it also has the added value of providing new reactivity and selectivity. This is especially important today, when chemists need to invent high-performance materials, intermediates, and products with the use of sustainable feedstocks and develop environmental remediation pathways. At the same time, time-resolved in situ monitoring and computational modeling are necessary for addressing fundamental questions about the atomistic, molecular, and electronic nature of mechanochemical reactivity. Integrating digitalization, robotics, and artificial intelligence tools promises to increase the reproducibility and scalability of mechanochemical processes. Further evolution of mechanochemistry is expected to have a transformative effect on the chemical industry.
KW - Mechanochemistry
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653962
DO - https://doi.org/10.1016/j.chempr.2025.102880
SN - 2451-9294
SP - 1
EP - 27
PB - Elsevier BV
AN - OPUS4-65396
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Onyenso, Gabriel
A1 - AI-Zawity, Jiwar
A1 - Farahbakhsh, Nastaran
A1 - Schardt, Annika
A1 - Yadigarli, Aydan
A1 - Vakamulla Raghu, Swathi Naidu
A1 - Engelhard, Carsten
A1 - Müller, Mareike
A1 - Schönherr, Holger
A1 - Killian, Manuela S.
T1 - Novel Ag-modified zirconia nanomaterials with antibacterial activity
N2 - The outcome of an implant procedure largely depends on the implant's surface properties. Biomaterials are now designed to have surfaces with multifunctionality, such as favorable tissue integration and the ability to combat bacterial adhesion and colonization. Herein, we report on a simple approach to improve the antibacterial properties of zirconia nanotubes (ZrNTs) coatings by decorating with silver nanoparticles (AgNP), achieved through electrochemical anodization of a zirconium–silver alloy (Zr–Ag). The AgNPs were shown to partially consist of Ag2O, potentially enhancing the availability of Ag+ ions for antibacterial activity. The modified ZrNTs were characterized using SEM, EDS, ToF-SIMS, and XPS to determine their structural morphology and chemical composition, and were further subjected to antibacterial testing. The silver and zirconium ion release behavior was monitored via ICP-MS. ZrNTs decorated with AgNP exhibit strong antimicrobial activity (>99% bacterial killing) against both S. aureus and E. coli. Antimicrobial tests indicate that the antibacterial activity against the Gram-positive pathogen S. aureus was improved by a factor of 100 compared to unmodified ZrNTs, while unmodified ZrNTs already showed a comparable reduction of viable Gram-negative E. coli. This strategy illustrates a straightforward and effective modification that optimizes the interface between the host environment and the biomaterial surface to meet the very important criteria of biocompatibility and active antibacterial response.
KW - Mass Spectrometry
KW - Nanoparticles
KW - Advanced Materials
KW - ICP-MS
KW - Antimicrobial material
KW - ToF-SIMS
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653990
DO - https://doi.org/10.1039/d5ra07099f
SN - 2046-2069
VL - 16
IS - 3
SP - 2286
EP - 2297
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65399
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schiaroli, Alice
A1 - Camplese, Davide
A1 - Scarponi, Giordano Emrys
A1 - Eberwein, Robert
A1 - Ustolin, Federico
A1 - Cozzani, Valerio
T1 - Modelling the behaviour of cryogenic liquid hydrogen tanks engulfed in fire
N2 - The safe use of liquid hydrogen as a clean fuel requires a deep understanding of its behaviour in accident scenarios. Among other scenarios, the possible involvement of cryogenic liquid hydrogen tanks in engulfing fires is of particular concern, due to the potentially severe consequences. This study proposes a computational fluid dynamic model suitable to simulate the behaviour of liquid hydrogen tanks equipped with multi-layer insulation (MLI) engulfed in fire. An original approach has been developed to assess the progressive degradation of the performance of the thermal insulation, that is crucial in determining the tank pressurization and failure. The model is validated against full-scale experimental fire tests. The outcomes of the model reproduce the progressive pressurization and the opening time of the pressure relief valve within 2 % error. The results demonstrate the importance of accounting for the dynamic evolution of the progressive degradation of the insulation when evaluating tank pressurization, and they highlight the limitations of empirical, simplified state-of-the-art approaches. Furthermore, the analysis evidences the key role of the fire temperature in governing tank response, stressing the need for proper fire characterization to support reliable modelling of fire scenarios and the development of emergency planning and mitigation strategies ensuring the structural integrity of liquid hydrogen tanks during fire attacks.
KW - LH2
KW - LNG
KW - Fire
KW - Tank
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652920
DO - https://doi.org/10.1016/j.psep.2025.108319
SN - 0957-5820
VL - 206
SP - 1
EP - 14
PB - Elsevier Ltd.
AN - OPUS4-65292
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Haugen, Øyvind P.
A1 - Polanco-Garriz, Itziar
A1 - Alcolea-Rodriguez, Victor
A1 - Portela, Raquel
A1 - Bæra, Rita
A1 - Sadeghiankaffash, Hamed
A1 - Hildebrandt, Jana
A1 - Ciornii, Dmitri
A1 - Altmann, Korinna
A1 - Barbero, Francesco
A1 - Fenoglio, Ivana
A1 - Reinosa, Julián J.
A1 - Fernández, José F.
A1 - Katsumiti, Alberto
A1 - Camassa, Laura M.A.
A1 - Wallin, Håkan
A1 - Zienolddiny-Narui, Shan
A1 - Afanou, Anani K.
T1 - Activation of Toll-like receptor 2 reveals microbial contamination beyond endotoxins on micro- and nanoplastics
N2 - Current literature on health hazards associated with micro- and nanoplastics (MNPs) is largely influenced by studies that insufficiently account for potential microbial contamination of their test materials. This may lead to misinterpretation of outcomes, as the test materials may be incorrectly considered pristine MNPs. The present study screened eight MNP test materials for microbial contaminants using Toll-like receptor (TLR) reporter cells for TLR2 and TLR4 and the commonly used Limulus amebocyte lysate (LAL) assay. Our results show that MNPs testing negative for endotoxins, based on the absence of TLR4 activation and negative LAL results, may still contain microbial ligands that selectively activate TLR2. Moreover, five of the eight MNP test materials contained microbial ligands capable of activating TLR2 and/or TLR4. Compared to the LAL assay, TLR4-based screening effectively detected endotoxin contamination. Overall, we found that the TLR reporter cell assay provides broader coverage than the LAL assay in detecting microbial ligands, which appear to be highly prevalent in MNP test materials.
KW - Nanoplastics
KW - Microplastics
KW - Microbial contamination
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653286
DO - https://doi.org/10.1016/j.tiv.2025.106190
SN - 0887-2333
VL - 112
SP - 1
EP - 8
PB - Elsevier Ltd.
AN - OPUS4-65328
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - You, Yi
A1 - Xue, Boyang
A1 - Riedel, Jens
T1 - Enhancement of LIBS plasma in air with organic solvent vapors
N2 - Laser-induced breakdown spectroscopy (LIBS) offers versatile, field-deployable elemental analysis; however, compact, high-repetition-rate nanosecond laser systems typically face constraints in power consumption and size, often compromising emission intensity and thus analytical performance. We demonstrate a significant improvement in LIBS signals through the controlled introduction of common organic solvent vapors into a sheath gas, with a diode-pumped solid-state laser (1064 nm, 2–28 kHz repetition rate, 450–600-μJ pulse energy). Optical and acoustic diagnostics reveal up to ca. 40-fold enhancement of the N II emission line at 567 nm when ambient air serves as the analyte. Maximal enhancement occurs at intermediate repetition rates of ca. 15 kHz, particularly at pulse energies approaching the optical breakdown threshold; this observation suggests a viable strategy for operating LIBS at lower pulse energies and higher repetition rates. Enhancement effects scale jointly with both vapor pressure and ionization energy of the organic species, with acetone and toluene markedly outperforming methanol and isopropanol. These findings provide a rational foundation for significantly improving the analytical performance of portable LIBS instruments without exceeding platform-specific constraints.
KW - LIBS
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653758
DO - https://doi.org/10.1016/j.sab.2025.107309
SN - 0584-8547
VL - 236
SP - 1
EP - 6
PB - Elsevier B.V.
AN - OPUS4-65375
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Holzer, Marco
A1 - Johansen, Sidsel M.
A1 - Christensen, Johan F.S.
A1 - Smedskjaer, Morten M.
A1 - Cicconi, Maria Rita
A1 - de Ligny, Dominique
A1 - Müller, Ralf
A1 - de Camargo, Andrea S.S.
A1 - Maaß, Robert
T1 - Direct connection between secondary relaxation mode and fracture toughness in alkali-aluminosilicate glasses
N2 - Oxide glasses are intrinsically brittle, lacking sufficient atomic-scale mechanisms that can relax mechanical stresses in the vicinity of a propagating crack. As a result, fracture is typically well-captured by considering local bond rupture at the crack tip. Here we demonstrate that barrier energies related to the low-temperature 𝛾-relaxation mode in alkali-aluminosilicate glasses are inversely related to the fracture toughness measured via standardized three-point bending fracture experiments. This holds true for both a series with varying cations (Li, Na, K) and one with varying Li concentration. The structural rationale for this finding is gained via Raman spectroscopy. The findings suggest that a fundamental structural relaxation mode measured on bulk specimens can serve as an effective guideline for fracture toughness of oxide glasses. Data for additional silicate glasses support this conclusion.
KW - Fracture toughness
KW - Oxide glass
KW - Mechanical properties
KW - Alkali-aluminosilicate glasses
KW - Internal friction
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-651540
DO - https://doi.org/10.1016/j.mtadv.2025.100669
SN - 2590-0498
VL - 29
SP - 1
EP - 10
PB - Elsevier Ltd.
CY - Amsterdam, Niederlande
AN - OPUS4-65154
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rashidi, Reza
A1 - Vaerst, Olivia
A1 - Riechers, Birte
A1 - Rösner, Harald
A1 - Wilde, Gerhard
A1 - Maaß, Robert
T1 - Atomic-scale strain fluctuations as an origin for elastic microstructures in metallic glasses
N2 - Metallic glasses (MGs) exhibit an elastic microstructure that spans from a few to hundreds of nanometers, the origin of which continues to remain poorly understood. Here we employ four-dimensional scanning transmission electron microscopy (4D-STEM) on a Zr65Cu25Al10 (at. %) bulk MG. Mapping local diffraction patterns over representative areas also probed elastically with automated nanoindentation, two comparable correlation length scales have been identified. Specifically, local diffraction patterns are analyzed with respect to their ellipticity, revealing systematic fluctuations between positive and negative volumetric strains. A power spectrum analysis of the strain fluctuations returns a dominant length scale of the order of 100 nm, which is very much compatible with what elastic property mapping indicates. Annealing reduces the magnitude of the statistical strain fluctuations, without strongly affecting the associated fluctuation length scale. These findings demonstrate that atomic-scale strains are very likely the origin of the structurally unexpected large elastic fluctuations obtained in nanoscale contact mechanics experiments.
KW - Metallic glass
KW - 4D-STEM
KW - Strain anisotropy
KW - Nanoindentation
KW - Elastic microstructure
KW - Heterogeneities
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654991
DO - https://doi.org/10.1016/j.actamat.2026.121982
SN - 1359-6454
VL - 308
SP - 1
EP - 8
PB - Elsevier Inc.
AN - OPUS4-65499
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gaal, Mate
A1 - Wernicke, Pascal
T1 - Improved air-coupled ultrasonic transmission using pulse compression
N2 - Air-coupled ultrasonic testing avoids contamination and reduces maintenance costs, but suffers from poor signal-to-noise ratio (SNR) due to impedance mismatch. Rather than developing new transducers, this study improves SNR through signal processing by adapting pulse compression from radar.We propose a method using unipolar square pulses to make pulse compression compatible with non-linear transducers such as ferroelectrets and thermoacoustic emitters. Instead of relying on analytical models, a reference transmission measurement served as the matched filter, simplifying implementation and ensuring adaptability across transducer types. We evaluated unipolar coded excitation and pulse compression on ultrasonic transmission through a 25mm polyvinyl chloride plate, varying code length and pulse delay. Significant SNR gains were observed across transducers, particularly with longer delays. These results confirm that pulse compression enhances peak localization and supports testing under low-SNR conditions.
Further experiments showed that pulse compression remains effective despite side lobe overlap and noise, provided the pulse delay is chosen appropriately. Although SNR prediction is limited by electrical and acoustic interference, the method consistently improves detection. Overall, the results demonstrate the feasibility of unipolar excitation coding for pulse compression in air-coupled ultrasonic testing, with practical value for thick or attenuating materials.
KW - Air-coupled ultrasound
KW - Coded excitation
KW - Pulse compression
KW - Transducers
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655005
DO - https://doi.org/10.1109/OJUFFC.2026.3659047
SN - 2694-0884
VL - 6
SP - 9
EP - 16
PB - Institute of Electrical and Electronics Engineers (IEEE)
AN - OPUS4-65500
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gerrits, Ruben
A1 - Stepec, Biwen An
A1 - Bäßler, Ralph
A1 - Becker, Roland
A1 - Dimper, Matthias
A1 - Feldmann, Ines
A1 - Goff, Kira L.
A1 - Günster, Jens
A1 - Hofmann, Andrea
A1 - Hesse, René
A1 - Kirstein, Sarah
A1 - Klein, Ulrich
A1 - Mauch, Tatjana
A1 - Neumann-Schaal, Meina
A1 - Özcan Sandikcioglu, Özlem
A1 - Taylor, Nicole M.
A1 - Schumacher, Julia
A1 - Shen, Yin
A1 - Strehlau, Heike
A1 - Weise, Matthias
A1 - Wolf, Jacqueline
A1 - Yurkov, Andrey
A1 - Gieg, Lisa M.
A1 - Gorbushina, Anna
T1 - A 30-year-old diesel tank: Fungal-dominated biofilms cause local corrosion of galvanised steel
N2 - The increased use of biodiesel is expected to lead to more microbial corrosion, fouling and fuel degradation issues. In this context, we have analysed the metal, fuel and microbiology of a fouled diesel tank which had been in service for over 30 years. The fuel itself, a B7 biodiesel blend, was not degraded, and—although no free water phase was visible—contained a water content of ~60 ppm. The microbial community was dominated by the fungus Amorphotheca resinae, which formed thick, patchy biofilms on the tank bottom and walls. The tank sheets, composed of galvanised carbon steel, were locally corroded underneath the biofilms, up to a depth of a third of the sheet thickness. On the biofilm-free surfaces, Zn coatings could still be observed. Taken together, A. resinae was shown to thrive in these water-poor conditions, likely enhancing corrosion through the removal of the protective Zn coatings.
KW - Fungal biofilms
KW - Biodiesel degradation mechanisms
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655014
DO - https://doi.org/10.1038/s41529-025-00731-2
SN - 2397-2106
VL - 10
IS - 1
SP - 1
EP - 14
PB - Springer Science and Business Media LLC
AN - OPUS4-65501
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gladrow, K.
A1 - Unkovskiy, A.
A1 - Yassine, J.
A1 - Gaertner, N.
A1 - Topolniak, Ievgeniia
A1 - Henning, N.
A1 - Schmidt, F.
T1 - The effect of nitrogen atmosphere during post-curing on cytotoxicity, polishability, flexural strength, and surface hardness of 3D-printed denture bases: an in vitro study
N2 - 3D printing is increasingly utilized in dentistry. Compared to traditional manufacturing methods, 3D printing provides advantages such as faster production times and the ability to create complex structures. Although biocompatible materials are available, many are only suitable for temporary applications. This study examines the impact of nitrogen-aided post-processing on the mechanical properties and cytotoxicity of 3D-printed denture bases, with the hypothesis that this post-processing will enhance material properties and decrease cytotoxicity. Specimens were fabricated from V-print dentbase (Voco GmbH, Cuxhaven, Germany) and post-processed either in nitrogen or air. The specimens were categorized into aged and non-aged groups. For comparison, specimens made from milled material were utilized. Vickers hardness, flexural strength, polishability, cytotoxicity, and degree of conversion were then assessed for all groups. The data were analyzed using a one-way ANOVA and Tukey HSD test for multiple comparisons, with a significance threshold of p < 0.05. Post-curing with nitrogen improved the degree of conversion, surface hardness, and biocompatibility of 3D-printed dental materials, confirming reduced cytotoxicity without impairing mechanical properties. Nitrogen increased polymerization and decreased harmful monomers, making it ideal for clinical applications in contact with the oral mucosa. Optimizing post-processing steps, such as curing in nitrogen, enhances biocompatibility while maintaining strength and hardness, ensuring better patient care in dental applications.
KW - Biocompatibility
KW - V-Print
KW - Cytotoxicity
KW - Nitrogen
KW - Dentistry
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654504
DO - https://doi.org/10.1007/s10856-026-07006-5
SN - 1573-4838
VL - 37
IS - 1
SP - 1
EP - 13
PB - Springer Science and Business Media LLC
AN - OPUS4-65450
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hübner, Martin
A1 - Dittmann, Florian
A1 - Kromm, Arne
A1 - Varfolomeev, Igor
A1 - Kannengiesser, Thomas
T1 - Enhancement of the fatigue strength by application of a low transformation temperature (LTT) welding consumable
N2 - Low transformation temperature (LTT) welding consumables offer a possibility to enhance fatigue strength in welded components without post-treatment. By lowering the martensite start temperature (MS), the volume expansion during transformation near ambient temperature reduces welding related tensile residual stresses in fatigue-critical areas. To evaluate this effect, longitudinal stiffeners were used, a LTT and conventional filler serve as welding consumable, also high frequency mechanical impact (HFMI) treatment was carried out. Three single-pass and six additional-pass sample series were investigated on residual stress and fatigue strength. The additional welds were applied in fatigue crack critical areas with different weld shapes, achieved by varying welding parameters. Mechanical tests on reference samples evaluated the properties of the diluted LTT welds. Although reduced toughness was observed, no fatigue cracks occurred in LTT single-pass weld roots. The fatigue strength at two million cycles increased from 81 MPa to 121 MPa compared to conventional welds, while HFMI reached 146 MPa. With an additional LTT weld pass the results varied from 138 MPa to 196 MPa, depending to the shape and residual stress state. The results show that LTT fillers effectively enhance fatigue performance, and that weld geometry and parameter selection are as critical as the chemical composition for maximizing the LTT effect.
CY - Genua, Italy
DA - 22.06.2025
KW - Low transformation temperature (LTT)
KW - Martensite start temperature
KW - Residual stress
KW - Longitudenal stiffener
KW - Fatigue strength
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654520
DO - https://doi.org/10.1007/s40194-026-02356-8
SP - 1
EP - 14
PB - Springer Nature
AN - OPUS4-65452
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kleba-Ehrhardt, Rafael
A1 - Dávila, Josué
A1 - Geissler, Johann
A1 - Mohr, Gunther
A1 - Schmidt, Johannes
A1 - Heinze, Christoph
A1 - Hilgenberg, Kai
A1 - Gurlo, Aleksander
A1 - Karl, David
T1 - Influence of Haynes 282 powder oxidation on powder properties and component quality in laser powder bed fusion
N2 - Reuse of powder in powder bed additive manufacturing is a common practice to enhance sustainability and reduce costs. However, the reusability of metal powder is limited by the oxidation of the powders. Even in a protective atmosphere, each build job leads to gradual oxidation of the powder, which has led to concerns about its impact on powder and part properties. Consequently, strict confidence intervals for oxygen content in nickel-based alloy feedstocks are enforced in the industry. Despite this, there is currently a lack of in-depth studies investigating the specific influence of oxygen on Haynes 282, a widely used nickel-based alloy. This study examines artificially aged Haynes 282 powder batches with oxygen content of 160 ppm, 330 ppm, 1050 ppm, and 1420 ppm. Detailed powder characterization was performed, including morphology, chemical composition, particle size, flowability, and packing behavior. Components were fabricated via PBF-LB/M to evaluate density and mechanical properties. The results showed that higher oxidation levels improved powder flowability and packing density. However, in manufactured parts, irregular melt tracks and increased surface roughness were observed, which could easily be removed by post-processing. No significant differences in density or mechanical properties at room temperature, such as tensile strength and elongation, were found. These findings indicate that H282 powder potentially remains suitable for reuse, even when the batches exhibit increased oxygen content, supporting discussions on revising the existing oxygen content confidence intervals for nickel-based alloys. The results highlight the potential for optimizing recycling strategies and reducing material waste in additive manufacturing processes.
KW - Additive manufacturing
KW - Powder bed fusion
KW - Powder characterization
KW - Powder oxidation
KW - Powder recycling
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654545
DO - https://doi.org/10.1016/j.addma.2025.105050
SN - 2214-8604
VL - 116
SP - 1
EP - 16
PB - Elsevier B.V.
AN - OPUS4-65454
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bartczak, Dorota
A1 - Sikora, Aneta
A1 - Goenaga-Infante, Heidi
A1 - Altmann, Korinna
A1 - Drexel, Roland
A1 - Meier, Florian
A1 - Alasonati, Enrica
A1 - Lelong, Marc
A1 - Cado, Florence
A1 - Chivas-Joly, Carine
A1 - Fadda, Marta
A1 - Sacco, Alessio
A1 - Rossi, Andrea Mario
A1 - Pröfrock, Daniel
A1 - Wippermann, Dominik
A1 - Barbero, Francesco
A1 - Fenoglio, Ivana
A1 - Booth, Andy M.
A1 - Sørensen, Lisbet
A1 - Igartua, Amaia
A1 - Wouters, Charlotte
A1 - Mast, Jan
A1 - Barbaresi, Marta
A1 - Rossi, Francesca
A1 - Piergiovanni, Maurizio
A1 - Mattarozzi, Monica
A1 - Careri, Maria
A1 - Caebergs, Thierry
A1 - Piette, Anne-Sophie
A1 - Parot, Jeremie
A1 - Giovannozzi, Andrea Mario
T1 - Multiparameter characterisation of a nano-polypropylene representative test material with fractionation, light scattering, high-resolution microscopy, spectroscopy, and spectrometry methods
N2 - Reference and quality control materials with comparable physicochemical properties to nanoplastic contaminants present in environmental and food nanoplastics are currently lacking. Here we report a nanoplastic polypropylene material prepared using a top-down approach involving mechanical fragmentation of larger plastics. The material was found to be homogeneous and stable in suspension and has been characterised for average particle size, size distribution range, particle number concentration, polypropylene mass fraction and inorganic impurity Content using a wide range of analytical methods, including AF4, cFFF, PTA, (MA)DLS, MALS, SEM, AFM, TEM, STEM, EDS,Raman, ICP-MS and pyGC-MS. The material was found to have a broad size distribution, ranging from 50 nm to over 200 nm, with the average particle size value dependent on the technique used to determine it. Particle number concentration ranged from 1.7–2.4 × 1010 g−1 , according to PTA. Spectroscopy techniques confirmed that the material was polypropylene, with evidence of aging due to an increased level of oxidation. The measured mass fraction was found to depend on the marker used and ranged between 3 and 5 μg g−1 . Inorganic impurities such as Si, Al, Mg, K, Na, S, Fe, Cl and Ca were also identified at ng g−1 levels. Comparability and complementarity across the measurement methods and techniques is also discussed.
KW - Polypropylene
KW - Nanoplastics
KW - Analytics
KW - Reference material
KW - Scattering methods
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654680
DO - https://doi.org/10.1039/D5EN00917K
SN - 2051-8153
SP - 1
EP - 15
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65468
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Avila Calderon, Luis Alexander
A1 - Schriever, Sina
A1 - Hang, Y.
A1 - Olbricht, Jürgen
A1 - Portella, P. D.
A1 - Skrotzki, Birgit
T1 - Creep reference data of single-crystal Ni-based superalloy CMSX-6
N2 - The article presents creep data for the single-crystal, [001]-oriented nickel-based superalloy CMSX-6, tested at a temperature of 980 °C under initial stresses ranging from 140 MPa to 230 MPa. The constant-load creep experiments were performed in accordance with DIN EN ISO 204:2019–4 standard within an ISO 17025 accredited laboratory. A total of 12 datasets are included, each of which includes the percentage creep extension as a function of time. The data series and associated metadata were systematically documented using a data schema specifically developed for creep data of single-crystal Ni-based superalloys. This dataset serves multiple purposes: it can be used to compare with one's own creep test results on similar materials, to verify testing setups (e.g., by replicating tests on the same or comparable materials), to calibrate and validate creep models, and to support alloy development efforts.
KW - NFDI MatWerk
KW - Referenzdaten
KW - Kriechen
KW - CMSX-6
KW - Digitalisierung
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654056
DO - https://doi.org/10.1016/j.dib.2025.112436
VL - 65
SP - 1
EP - 11
PB - Elsevier
AN - OPUS4-65405
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rahner, E.
A1 - Thiele, T.
A1 - Voss, Heike
A1 - Müller, F.A.
A1 - Bonse, Jörn
A1 - Gräf, S.
T1 - Objective, high-throughput regularity quantification of laser-induced periodic surface structures (LIPSS)
N2 - The growing demand for precise surface functionalization through laser-generated periodic surface structures highlights the necessity for efficient, reproducible, and objective evaluation methods to evaluate their structural regularity. We introduce ReguΛarity (v.1.2.7), a freely available, Python-based software with a graphical user interface for the automated, quantitative assessment of the regularity of laser-induced periodic surfaces structures (LIPSS), obtained from optical microscopy, SEM, or AFM. The software integrates image segmentation, one- and two-dimensional Fourier analyses, and gradient-based orientation determination to facilitate a comprehensive regularity analysis of grating-like (quasi-)periodic surface patterns with spatial periods Λ. This is achieved through the proposed regularity tuple R, composed of five key parameters: the normalized spread of the spatial period RΛ,2D (from 2D-FT), the normalized variation of the most frequent spatial period RΛ (from 1D-FT), the Gini coefficient G, the Dispersion of the LIPSS Orientation Angle δθ (DLOA), and the mean phase deviation . To demonstrate its applicability, we compare ideal sinusoidal patterns with SEM images obtained from LIPSS on stainless steel (AISI 316L) and aluminum alloy (AlMg5) surfaces, confirming the software’s ability to objectively distinguish between varying levels of structural regularity. ReguΛarity facilitates high-throughput analysis and data-driven process optimization in surface engineering and laser materials processing.
KW - Laser-induced periodic surface structures (LIPSS)
KW - Image processing
KW - Regularity quantification
KW - Fourier analysis
KW - Structural homogeneity
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654070
DO - https://doi.org/10.1016/j.apsusc.2026.165919
SN - 0169-4332
VL - 726
SP - 1
EP - 12
PB - Elsevier B.V.
AN - OPUS4-65407
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pittrich, Tim
A1 - Jansen, Daniel
A1 - Weise, Frank
A1 - Stelzner, Ludwig
A1 - Dehn, Frank
T1 - Thermal decomposition in blended cement systems and its effect on fire-induced concrete spalling: Insights from XRD and TGA
N2 - Blended cements are gaining increasing popularity due to their lower CO2-footprint in comparison to ordinary Portland cement (OPC). However, this growing use raises the potential risk of buildings made with blended cement concrete being exposed to fire, which can lead to heavy damages caused by explosive concrete spalling. It has already been shown that the cement type strongly influences the fire-induced concrete spalling and the thermally induced moisture transport, however, to understand the mechanisms behind these findings the thermal decomposition behavior of the cementitious matrix must be investigated more systematically. Therefore, the phase content of three blended cement pastes (CEM II/A-LL, CEM III/A and CEM II/B-Q) was studied in comparison with a Portland cement paste (CEM I) after temperature exposure to 20 ◦C, 105 ◦C, 300 ◦C and 500 ◦C. Clear differences in the initial phase composition and their dehydration behavior between the individual cement types were recognized. In conclusion, blended cements showed lower amounts of AFt and AFm phases and additionally lower amounts of portlandite and C-(A)-S-H were found in CEM III/A and CEM II/B-Q pastes. The results suggest that higher AFt and AFm contents in CEM I, which are associated with greater water release at relatively low temperatures may ultimately reduce the spalling risk. Furthermore, C-(A)-S-H in CEM III/A and CEM II/B-Q showed increased thermal stability and large amounts of non-hydrated phases were found in every blended cement paste. Both of those aspects might contribute to thermomechanical spalling and the overall increased spalling susceptibility observed in blended cement concrete.
KW - Fire concrete spalling
KW - High temperatures
KW - Blended cements
KW - Dehydration
KW - XRD
KW - TGA
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653698
DO - https://doi.org/10.1016/j.cscm.2026.e05784
SN - 2214-5095
VL - 24
SP - 1
EP - 14
PB - Elsevier Ltd.
AN - OPUS4-65369
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Robens-Radermacher, Annika
A1 - Schmidt, Wolfram
A1 - Unger, Jörg F.
A1 - Mezhov, Alexander
T1 - Characterization of temperature influence on the structural build-up of 3D printed concrete
N2 - 3D concrete printing technologies enhance design freedom while reducing material use and costs without the need for formwork. Thereby, structural build-up is the key property governing stability and early strength evolution of 3D printed concrete after placement. Structural build-up is influenced by various factors, i.e., environmental conditions such as temperature. In this paper, the influence of ambient temperature on structural build-up was investigated through experimental and numerical approaches. Three experimental setups (small amplitude oscillatory shear, constant shear rate, and small amplitude oscillatory extensional tests) were applied to materials of increasing complexity under varying temperature conditions. A common modeling framework based on the maturity approach was developed to capture the time and temperature evolution. A stochastic framework was employed to estimate the unknown model parameters using experimental data. Experimental results demonstrate a significant temperature influence on structural build-up, consistent across all test setups and materials. The calibrated models successfully predict the structural build-up under different temperatures, confirming the applicability of the maturity approach to rheological parameters at early age. Furthermore, the stochastic parameter estimation allows a correct quantification of the uncertainties, enhancing model reliability. The comparison of two time evolution formulations indicates that a model with an additional linear stage is required for predicting the increase of the storage moduli (
$${G}{\prime}$$
G
′
,
$${E}{\prime}$$
E
′
). In conclusion, the study demonstrates that temperature significantly affects the structural build-up, and that the proposed modeling approach allows to predict this behavior.
KW - Structural build-up
KW - 3D concrete printing
KW - Rheology
KW - Temperature influence
KW - Modeling
KW - Green intelligent building
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654138
DO - https://doi.org/10.1617/s11527-025-02931-3
SN - 1359-5997
VL - 59
IS - 2
SP - 1
EP - 20
PB - Springer Science and Business Media LLC
AN - OPUS4-65413
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Yu, Jialu
A1 - Oelze, Marcus
A1 - Schannor, Mathias
A1 - Nordstad, Simon
A1 - Vogl, Jochen
T1 - New Potential Haematite and Magnetite Reference Materials for Iron Isotope Measurements by Solution Nebulisation MC ‐ ICP ‐ MS and by In Situ ns ‐ LA ‐ MC ‐ ICP ‐ MS
N2 - Iron isotope ratios of haematite (Fe2O3) and magnetite (Fe3O4) provide insights into geochemical, environmental and planetary processes. In most studies, Fe isotope measurements are commonly performed using solution nebulisation multi-collector inductively coupled plasma-mass spectrometry (SN-MC-ICP-MS). Nanosecond laser ablation multi-collector inductively coupled plasma-mass spectrometry (ns-LA-MC-ICP-MS) requires minimal sample preparation, and provides spatially resolved variation of iron isotopes at micro-scale. However, homogeneous and matrix-matched haematite/magnetite reference materials are lacking for precise in situ isotopic measurement. The iron isotope ratios of two potential reference materials resembling natural haematite (HMIE-NP-B01) and natural magnetite (MAKP-NP-B01) were characterised. Size fractions between 5–63 μm of the powdered Fe oxides were milled to nanoparticles, freeze-dried, homogenised, and pressed into pellets. The materials were then evaluated using SN-MC-ICP-MS and LA-MC-ICP-MS. Sample powders of the two materials were measured by SN-MC-ICPMS after sample digestion and column separation and pressed pellets were analysed directly via ns-LA-MC-ICP-MS. In both cases iron isotope delta values are reported relative to the certified reference material IRMM-014, used as the bracketing standard (calibrator). The solution measurements yielded δ56Fe values of -0.25 ± 0.08‰ (N = 13, 2s) for HMIE-NP-B01, and -0.05 ± 0.09‰ (N = 12, 2s) for MAKP-NP-B01, considered as the preferred Fe isotope delta values. In situ isotopic analysis via ns-LA-MC-ICP-MS yielded δ56Fe values of -0.28 ± 0.28‰ (N = 19, 2s) for HMIE-NP-B01 and -0.12 ± 0.24‰ (N = 22, 2s) for MAKP-NP-B01, consistent with the solution Fe isotope data. The homogeneity of Fe isotopes of the pellets was evaluated by ns-LA-MC-ICP-MS analyses of three different positions to further confirm that both materials are isotopically homogeneous. Both materials can be considered as potential quality control and bracketing reference materials for Fe isotopic measurements by in situ ns-LA-MC-ICP-MS analysis.
KW - Laser ablation
KW - Fe isotope
KW - Fe-oxides
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654755
DO - https://doi.org/10.1111/ggr.70037
SN - 1639-4488
SP - 1
EP - 12
PB - John Wiley & Sons Ltd.
AN - OPUS4-65475
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schusterbauer, Robert
A1 - Mrkwitschka, Paul
A1 - Sahre, Mario
A1 - Corrao, Elena
A1 - Zurutuza, Amaia
A1 - Doolin, Alexander
A1 - Pellegrino, Francesco
A1 - Radnik, Jörg
A1 - Donskyi, Ievgen S.
A1 - Hodoroaba, Vasile-Dan
T1 - Correlative Chemical Imaging to Reveal the Nature of Different Commercial Graphene Materials
N2 - Proper physicochemical characterization of advanced materials and complex industrial composites remains a significant challenge, particularly for nanomaterials, whose nanoscale dimensions and mostly complex chemistry challenge the analysis. In this work, we employed a correlative analytical approach that integrates atomic force microscopy (AFM), scanning electron microscopy (SEM) coupled with energy‐dispersive X‐ray spectroscopy (EDS), time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS), Auger electron spectroscopy (AES), and Raman spectroscopy. This combination enables detailed chemical and structural characterization with sub‐micrometer spatial resolution. Three commercial graphene‐based materials of varying complexity were selected and investigated to test the analytical performance of this approach. Furthermore, one of the commercial graphene oxide samples was chemically functionalized via amination and fluorination. This allowed us to assess how surface modifications influence both the material properties and the limits of the applied analytical techniques.
KW - Analytical methods
KW - Commercial products
KW - Correlative analysis
KW - Graphene
KW - Surface imaging
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654765
DO - https://doi.org/10.1002/smtd.202502344
SN - 2366-9608
SP - 1
EP - 10
PB - Wiley VHC-Verlag
AN - OPUS4-65476
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gugin, Nikita
A1 - Schwab, Alexander
A1 - Carraro, Francesco
A1 - Tavernaro, Isabella
A1 - Falkenhagen, Jana
A1 - Villajos, Jose
A1 - Falcaro, Paolo
A1 - Emmerling, Franziska
T1 - ZIF-8-based biocomposites via reactive extrusion: towards industrial-scale manufacturing
N2 - Mechanochemistry, a sustainable synthetic method that minimizes solvent use, has shown great promise in producing metal–organic framework (MOF)-based biocomposites through ball milling. While ball milling offers fast reaction times, biocompatible conditions, and access to previously unattainable biocomposites, it is a batch-type process typically limited to gram-scale production, which is insufficient to meet commercial capacity. We introduce a scalable approach for the continuous solid-state production of MOF-based biocomposites. Our study commences with model batch reactions to examine the encapsulation of various biomolecules into Zeolitic Imidazolate Framework-8 (ZIF-8) via hand mixing, establishing a foundation for upscaling. Subsequently, the process is scaled up using reactive extrusion, enabling continuous and reproducible kilogram-scale production of bovine serum albumin (BSA)@ZIF-8 with tunable protein loading. Furthermore, we achieve the one-step formation of shaped ZIF-8 extrudates encapsulating clinical therapeutic hyaluronic acid (HA). Upon release of HA from the composite, the molecular weight of HA is preserved, highlighting the industrial potential of reactive extrusion for the cost-effective and reliable manufacturing of biocomposites for drug-delivery applications.
KW - Mechanochemistry
KW - Extrusion
KW - Biocompoites
KW - MOFs
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654777
DO - https://doi.org/10.1039/D5TA08276E
SN - 2050-7496
SP - 1
EP - 14
PB - Royal Society of Chemistry
AN - OPUS4-65477
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kästle, Emanuel D.
A1 - Duffner, Eric
A1 - Popiela, Bartosz
A1 - Ghaznavi, Ali
T1 - Monitoring Failure of Composite Pressure Vessels with Acoustic Emissions
N2 - Two carbon fiber reinforced type IV pressure vessels are subjected to step-wise pressurization until burst, while monitored using acoustic emissions (AE). Unlike most prior studies, AE data is collected throughout the entire damage progression. The vessels, manufactured with differing parameters, failed in distinct composite layers – A-type in the hoop layers and B-type in the helical layers. The AE signals are evaluated to study material degradation and identify fiber breaks as signs of critical damage accumulation. The signals are distributed randomly across the surface, with localized accumulation only minutes before rupture, close to the rupture plane. The difference in manufacturing parameters did not result in any clear difference in the AE activity. Felicity and Shelby ratios show consistent decline with increasing pressure, suggesting potential for damage assessment and burst prediction. It is discussed how these ratios are affected by coupling quality of the AE sensors, the shape of the pressurization profile and prior loadings. Different signal features based on the amplitude and the frequency content are extracted for a classification into failure mechanisms. Based on previous studies, AE signals corresponding to fiber breaks have a characteristic high-frequency spectrum and show a delay in occurrence, with an increase in the number of breaking fibers towards the end of the experiment. Indeed, high frequency signals tend to occur later and signals in specific peak-frequency ranges (350 – 400 kHz, 500 kHz) somewhat resemble the expected behavior. However, the dataset is too variable and too incongruent for any clear interpretations. Likely reasons are signal propagation effects, the complex composite structure, simultaneous occurrence of signals and measurement uncertainties. A review of relevant studies is provided to show that similar issues affect also previous works. Successfully identifying fiber breaks in large-scale, complex composite structures based on AE data, and turning this into an applicable health-monitoring technique, therefore remains a challenge.
KW - Acoustic emission testing
KW - Composite pressure vessels
KW - Damage classification in fiber reinforced polymers
KW - Felicity ratio
KW - Composite failure
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654852
DO - https://doi.org/10.1007/s10921-025-01319-1
SN - 0195-9298
VL - 45
IS - 1
SP - 1
EP - 19
PB - Springer Science and Business Media LLC
AN - OPUS4-65485
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wallis, Theophilus
A1 - Ratanaphan, Sutatch
A1 - Darvishi Kamachali, Reza
T1 - Linking atomistic and phase-field modeling of grain boundaries I: Coarse-graining atomistic structures
N2 - The longstanding gap between atomistic and mesoscale simulations partly lies in the absence of a direct, physically grounded connection between atomic structure and mesoscale fields. In this work, we present a robust coarse-graining approach to systematically investigate the connection between phase-field and atomistic simulations of grain boundaries (GBs). The atomistic structures of 408 GBs in BCC-Fe and -Mo were studies to compute and analyze a continuous atomic density field. We discover a fundamental relationship between the GB density---defined as the average atomic density at the GB plane---and the GB excess free volume, an integral property of the boundary. An almost perfect linear correlation between the GB atomic density and GB excess free volume is identified. We also show that the width of BCC GBs, when scaled by the lattice constant, approaches a universal constant value. The relationships among GB density, width, and energy are systematically examined for various GB planes, and the GB energy--density correlations are classified with respect to GB types. It turns out that the atomic planes forming the GB strongly influence both the GB density and excess volume. The current results establish a dependable framework to bridge across scales, enabling density-based phase-field modeling of GBs with atomistic fidelity and enhancing the predictive reliability of mesoscale simulations.
KW - Density-based model
KW - Grain boundary structure
KW - Grain boundary thermodynamic
KW - Atomistic simulations
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654872
DO - https://doi.org/10.1016/j.actamat.2025.121786
SN - 1359-6454
VL - 305
SP - 1
EP - 14
PB - Elsevier Inc.
AN - OPUS4-65487
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pavlidis, Sotirios
A1 - Fischer, Eric W.
A1 - Opis-Basilio, Amanda
A1 - Bera, Ayan
A1 - Guilherme Buzanich, Ana
A1 - Álvarez-Sánchez, María
A1 - Wittek, Severin
A1 - Emmerling, Franziska
A1 - Ray, Kallol
A1 - Roemelt, Michael
A1 - Abbenseth, Josh
T1 - Ambiphilic Reactivity and Switchable Methyl Transfer at a T-Shaped Bi(NNN) Complex Enabled by a Redox-Active Pincer Ligand
N2 - We report the transition-metal-like reactivity of a geometrically constrained, ambiphilic bismuth(III) trisamide. Planarization of the Bi(III) center unlocks Bi−C bond formation when reacted with mild electrophiles (alkyl iodides and triflates) accompanied by two-electron oxidation of the utilized NNN pincer nligand. The preservation of the bismuth oxidation state is confirmed by single-crystal X-ray diffraction and X-ray absorption spectroscopy and corroborated by theoretical calculations. Sequential reduction of the oxidized ligand framework alters the reactivity of a generated Bi−Me unit, enabling controlled access to methyl cation, radical, and anion equivalents. The full [Bi(Me)(NNN)]+/•/− redox series was comprehensively characterized using NMR and EPR spectroscopy as well as spectro-electrochemistry. This work represents the first example of ligand-assisted, redox-neutral C−X bond splitting at bismuth, establishing a new paradigm for synthetic bismuth chemistry.
KW - Pincer ligand
KW - XAS
KW - Redox
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654948
DO - https://doi.org/10.1021/jacs.5c18955
SN - 0002-7863
VL - 148
IS - 2
SP - 2683
EP - 2692
PB - American Chemical Society (ACS)
AN - OPUS4-65494
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wallis, Theophilus
A1 - Darvishi Kamachali, Reza
T1 - Linking atomistic and phase-field modeling of grain boundaries II: Incorporating atomistic potentials into free energy functional
N2 - The density-based phase-field model for grain boundary (GB) thermodynamics and kinetics has offered a broad range of applications in alloy and microstructure design. Originally, this model is based on a potential energy terms that is connected to the cohesive energy of a given substance. A more rigorous approach, however, is a full consideration of an interatomic potential over the possible range of distance and therefore density. In Manuscript I of this series, we developed and thoroughly analyzed the coarse-graining of atomistic GB structures. In this work (Manuscript II), we complete the coupling between atomic and mesoscale modeling of GBs by incorporating the full interatomic potentials into the density-based free energy functional. Using GB energies calculated from atomistic simulations, the coarse-graining approach and the atomistic-integrated density-based Gibbs free energy, we effectively evaluate the density gradient energy coefficient. We found that coupling the density-based model with atomistic potentials reveal physically-sound trends in the GB equilibrium properties. A universal equation was derived to describe the potential energy contribution to the GB energy and the gradient energy coefficient for BCC-Fe and -Mo GBs, similar to the universal equation for GB excess free volume presented in Manuscript I. The proposed approach provides a mesoscale density-based model rooted in atomic-scale characteristics for reliable predictions of GB properties.
KW - Density-based model
KW - Phase-field
KW - Grain boundary structure
KW - Grain boundary thermodynamics
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654904
DO - https://doi.org/10.1016/j.actamat.2025.121787
SN - 1359-6454
VL - 305
SP - 1
EP - 17
PB - Elsevier
AN - OPUS4-65490
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Vogel, Christian
A1 - Helfenstein, J.
A1 - Massey, M.
A1 - Kretzschmar, R.
A1 - Schade, U.
A1 - Verel, R.
A1 - Chadwick, O.
A1 - Frossard, E.
T1 - Spectroscopic analysis shows crandallite can be a major component of soil phosphorus
N2 - Phosphorus (P) bioavailability is crucial for the productivity of natural and agricultural ecosystems, and soil P speciation plays a major role therein. Better understanding of P forms present in soil is thus essential to predict bioavailability. However, P speciation studies are only as powerful as the reference spectra used to interpret them, and most studies rely on a limited set of reference spectra. Most studies on soil P forms differentiate between Ca-bound P (e.g. apatite), organic P, Fe-bound P, and Al-bound P. In our analysis of a Ca, Al, and P rich soil from the Kohala region of Hawaii, we identified the mineral crandallite, CaAl3(PO4)2(OH)5·H2O, a mineral previously not considered to play a significant role in soils. Crandallite was first identified with powder X-ray diffraction. Subsequently reference spectra were collected, and the presence of crandallite was confirmed using micro-focused P K-edge X-ray absorption near edge structure (XANES) spectroscopy, micro-infrared spectroscopy, and solid-state 31P nuclear magnetic resonance (NMR) spectroscopy. Crandallite XANES spectra were distinct from other common XANES spectra due to the presence of features in the post-edge region of the spectrum. Linear combination fitting of bulk P K-edge XANES spectra allowed the determination of the proportion of crandallite to the total P content, indicating that crandallite comprises up to half, possibly even more of the soil P in the samples. Crandallite is therefore an important and potentially overlooked component of soil P, which pedogenically forms in soils with high P, Al, and Ca contents, where it could play an important role in P bioavailability.
KW - Phosphorus
KW - XANES spectrosocpy
KW - Infrared spectroscopy
KW - NMR spectrocopy
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654968
DO - https://doi.org/10.1016/j.geoderma.2026.117712
SN - 0016-7061
VL - 467
SP - 1
EP - 10
PB - Elsevier B.V.
AN - OPUS4-65496
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tóth, Péter
A1 - Hofmann‐Böllinghaus, Anja
A1 - Dumont, Fabien
A1 - Anderson, Johan
A1 - Sjöström, Johan
A1 - Bergius, Mikael
A1 - Chiva, Roman
A1 - Lalu, Octavian
T1 - Finalisation of the European Approach to Assess the Fire Performance of Facades—Brief Information on the Outcome of the Project
N2 - This research was conducted within the framework of project SI2.825082, funded by the European Commission—DG GROW. The project's objective was to finalise a European approach for assessing the fire performance of façades under medium and large fire exposure conditions. The national standards BS 8414‐1:2020/BS 8414‐2:2020 and DIN 4102‐20:2017 served as the foundation for developing the new assessment method. As part of the project, a theoretical round robin, initial testing activities and a large‐scale experimental round robin were carried out. The theoretical round robin aimed to examine how different laboratories interpreted the preliminary assessment method. Subsequently, the initial testing phase explored the design of the fire source, combustion chamber and secondary opening. The experimental round robin involved testing four façade systems across three laboratories using the assessment method documents, resulting in 12 tests for medium‐scale and 12 for large‐scale exposure—24 tests in total. These tests provided data to develop a calibration scheme and define appropriate performance criteria for classification. In this paper, the representatives of the project consortium summarise the research process and outline the proposed testing and evaluation methodology, which is intended to form the foundation of a future European testing standard for façades. The article also highlights the need for further research to establish rules for extended application of test results.
KW - Facade
KW - Testing
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654731
DO - https://doi.org/10.1002/fam.70042
SN - 0308-0501
SP - 1
EP - 27
PB - John Wiley & Sons Ltd.
AN - OPUS4-65473
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wiesner, Yosri
A1 - Eisentraut, Paul
A1 - Altmann, Korinna
T1 - One Year Observation of Microplastic Concentrations in the River Rhine
N2 - In recent years, the quantification of microplastics (MP) in aquatic environments has gained increasing attention, particularly regarding their environmental distribution and potential exposure levels. Environmentally relevant exposure data are still essential for a realistic risk assessment of the harmful health potential of microplastics in freshwater systems. This study addresses a large data set of MP concentrations analyzed and processed under statistical aspects and provides mass concentrations as well as associated size fractions of the detected MP. Over a 12 month period, samples were collected at three locations and analyzed across three particle size fractions (100−500 μm, 50−100 μm, and 10−50 μm) using thermalextraction desorption-gas chromatography/mass spectrometry (TED-GC/MS). The most prevalent polymers identified were polyethylene (PE), polypropylene (PP), polystyrene (PS), styrene−butadiene rubber (SBR), and natural rubber (NR). Statistical analyses, including principal component and cluster analysis, revealed size-dependent patterns,minor seasonal variation and spatial variations. These findings are particularly significant for ecotoxicological research and regulatory development, especially regarding tire abrasion a rarely quantified but potentially harmful MP source. The study contributes aluable data for future environmental monitoring and supports EU directives on wastewater and drinking water quality
KW - TED-GC/MS
KW - Microplastics
KW - Environment
KW - Monitoring
KW - Reference data
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654669
DO - https://doi.org/10.1021/acsestwater.5c00530
SN - 2690-0637
SP - 1
EP - 10
PB - American Chemical Society (ACS)
AN - OPUS4-65466
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sobczak, M.
A1 - Lecompagnon, Julien
A1 - Hirsch, Philipp Daniel
A1 - Pieczonka, Ł.
A1 - Ziegler, Mathias
T1 - Impact damage characterization on CFRP parts using laser line scanning active thermography
N2 - This study presents a dual-path data processing framework for the detection and characterization of barely visible impact damage (BVID) in carbon-fiber-reinforced polymer (CFRP) structures using laser line thermography (LLT). A robotic LLT system was used to scan impacted CFRP specimens, and the resulting thermal sequences were analyzed using two complementary methods: full thermogram reconstruction followed by Pulse Phase Thermography (PPT) to detect subsurface delaminations, and Time-Summed Gradient Filtering (TSGF) to enhance surface-breaking cracks. Both processing paths produced interpretable results that were fused into a unified combined image and overlay mask, enabling simultaneous visualization of different defect types from a single scan. Quantitative analysis was performed on the binary masks to extract defect dimensions and Signal-to-noise ratio (SNR) values. The results demonstrated that delaminations and multiple cracks could be accurately detected and spatially distinguished, with good agreement to reference methods such as flash thermography and vibrothermography. This work highlights the potential of LLT as a versatile and scalable inspection technique, where multimodal defect detection and segmentation can be achieved through targeted processing and data fusion strategies.
KW - Active thermography
KW - CFRP
KW - Laser line scanning
KW - Delamination
KW - Cracks
KW - BVID
KW - NDT
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654097
DO - https://doi.org/10.1016/j.compositesb.2026.113425
SN - 1359-8368
VL - 313
SP - 1
EP - 9
PB - Elsevier Ltd.
AN - OPUS4-65409
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schröder, Nina
A1 - Uhlig, Marvin
A1 - Kromm, Arne
A1 - Schröpfer, Dirk
A1 - Höfer, Kevin
A1 - Hensel, Jonas
A1 - Kannengießer, Thomas
T1 - Challenges in the evaluation of the weldability of old mild steels for future use
N2 - For reasons of sustainability and cost efficiency, there is an increasing trend in the steel-processing industry to retrofit existing structures, avoiding costly shutdowns or dismantling. Although welding is a cost-effective joining method, it is rarely applied to old steels, whereas riveted or bolted connections are often uneconomical. Repair and refurbishment frequently require the replacement of damaged material or the creation of dissimilar old–new steel joints. Due to the varied manufacturing processes of historical steels, not all twentieth-century steels are inherently weldable, making an initial assessment of weldability
essential. In this study, a historical non-deoxidized mild steel (produced by Siemens–Martin processing) originating from the construction of the Berlin Radio Tower (erected in 1926) was investigated using dilatometry to analyze its welding behavior. A database of welding CCT diagrams and HAZ simulations was established to support practice-oriented welding experiments, providing key insights into their weld-metallurgical behavior and weldability. Furthermore, initial welding trials were conducted, and the local residual stress states in dissimilar old–new steel joints were determined. These foundational investigations are critical for the development of innovative, load-adapted welding concepts for the repair and refurbishment of existing old-steel infrastructure in Germany.
KW - Old mild steels
KW - Repair welding
KW - Weldability
KW - Thermo-physical simulation
KW - CCT diagrams
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654784
DO - https://doi.org/10.1007/s40194-026-02366-6
SN - 1878-6669
SP - 1
EP - 14
PB - Springer nature
AN - OPUS4-65478
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - George, Janine
A1 - Ouellet-Plamondon, Claudiane
A1 - Reyes, Kristofer
T1 - Introduction to the “Accelerate Conference 2023–2024” themed collection
N2 - The collection showcases the ways in which automation, machine learning and robotics are transforming experimental materials science and chemistry into continuous, computationally integrated processes. It features innovations regarding autonomous laboratories, Bayesian optimisation, high-throughput experimentation and computation, and AI-driven literature extraction, which simplify and scale up materials discovery. Together, these works outline a modular, responsible framework for accelerating scientific progress through human-guided, data-driven autonomy.
KW - Automation
KW - Materials Acceleration Platforms
KW - Synthesizability
KW - Workflows
KW - Large Language Models
KW - Ontologies
KW - Materials Discovery
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654658
DO - https://doi.org/10.1039/d5dd90057c
SN - 2635-098X
SP - 1
EP - 2
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65465
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Spitzer, Stefan
A1 - Amyotte, P.
A1 - Salzano, E.
T1 - Explosion behavior of hybrid mixtures
N2 - Flammable mixtures of dusts with gases or liquids occur in the process and energy industries. Most research about these so-called "hybrid mixtures" was, and still is, about coal dust with the admixture of methane because of their occurrence in the mining industry. In the modern industry, hybrid mixture explosions play an increasing role in many existing processes like spray-drying, or in emerging technologies like the direct reduction of iron ore with hydrogen or nuclear/fusion reactors. While some safety characteristics of one of the component substances stay the same or are unaffected by the concentrations that occur in the process, others are severely influenced by only traces of the other substance.
This review paper shows in which processes and applications hybrid mixtures pose a risk and gives an overview of the research conducted in the last 150 years. Findings that are reproducible and represent current proven knowledge are stated and compared to each safety characteristic containing only solid particles, gases or liquids as combustible substances. Additionally, fundamental studies on the mechanisms of flame propagation in hybrid mixtures are reviewed. The significance of these studies in enhancing our understanding of explosion behaviors in hybrid mixtures is also discussed. An outlook on what has been missing so far in the literature, is also given comparing the knowledge of single substances with their mixtures, why this might not have been investigated, and where the challenges lie.
KW - Hybrid mixtures
KW - Safety characteristics
KW - Combustion regimes
KW - Industrial explosions
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654013
DO - https://doi.org/10.1016/j.pecs.2025.101276
SN - 0360-1285
VL - 113
SP - 1
EP - 24
PB - Elsevier
CY - Amsterdam
AN - OPUS4-65401
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Krause, Christina
A1 - Szymoniak, Paulina
A1 - Lohstroh, W.
A1 - Juranyi, F.
A1 - Zamponi, M.
A1 - Frick, B.
A1 - Al-Sabbagh, Dominik
A1 - Emmerling, Franziska
A1 - Zorn, R.
A1 - Schönhals, Andreas
T1 - Complex molecular dynamics of symmetric model discotic liquid crystals: Comparison of Hexakis(hepta-alkanoyloxy)triphenylene (HOT6) with Hexakis(hexa-alkyloxy)triphenylene (HAT6)
N2 - This study investigates the complex molecular dynamics of discotic liquid crystals (DLCs) by comparing two structurally similar compounds: Hexakis(hepta-alkanoyloxy)triphenylene (HOT6) and Hexakis(hexa-alkyloxy)triphenylene (HAT6) having the same triphenyl core and the same length of the alkyl side chain. The difference of both materials is that the alkyl chain is linked by an oxygen bridge to the triphenylene core for HAT6 and by a ester group for HOT6. Using a combination of broadband dielectric spectroscopy, differential scanning calorimetry, X-ray scattering, and neutron scattering techniques, the research explores the glass transition phenomena and relaxation processes in these materials. HOT6, featuring ester linkages, exhibits distinct dynamic behavior compared to HAT6, including two separate glass transitions indicated by the 1- and 2-relaxation found by dielectric spectroscopy which are assigned to the glassy dynamics of the alkyl side chain in the intercolumnar space and that of the columns, respectively. The study reveals that the ester group in HOT6 leads to increased molecular rigidity and altered packing in the intercolumnar space, as evidenced by X-ray scattering and the vibrational density of states. Neutron scattering confirms localized methyl group rotations and a further relaxation process which relates to the -relaxation revealed by dielectric spectroscopy. The findings contribute to a deeper understanding of glassy dynamics in partially ordered systems and highlight the influence of molecular architecture on relaxation behavior in DLCs.
KW - Discotic Liquid Crystals
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655171
DO - https://doi.org/10.1039/d5sm01247c
SP - 1
EP - 17
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65517
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rodriguez, Santiago
A1 - Kumanski, Sylvain
A1 - Ayed, Zeineb
A1 - Fournet, Aurélie
A1 - Bouanchaud, Charlène
A1 - Sagar, Amin
A1 - Allemand, Frédéric
A1 - Baulin, Vladimir A.
A1 - Resch‐Genger, Ute
A1 - Cortés, Juan
A1 - Sibille, Nathalie
A1 - Chirot, Fabien
A1 - Wegner, Karl David
A1 - Antoine, Rodolphe
A1 - Le Guével, Xavier
A1 - Bernadó, Pau
T1 - Programming the Optoelectronic Properties of Atomically Precise Gold Nanoclusters Using the Conformational Landscape of Intrinsically Disordered Proteins
N2 - The rational design of hybrid nanomaterials with precisely controlled properties remains a central challenge in materials science. While atomically precise gold nanoclusters (Au‐NCs) offer molecule‐like control over a metallic core, tuning their optoelectronic behavior via surface engineering is often empirically driven. Here, we establish a design principle by demonstrating that the conformational landscape of intrinsically disordered proteins (IDP) can be used as a programmable scaffold to rationally modulate the photophysical properties of a covalently bound Au‐NC. We synthesized a series of bioconjugates between Au 25 nanoclusters and bioengineered IDPs containing a variable number of cysteine anchoring points. A combination of mass spectrometry, small‐angle X‐ray scattering, and modeling on the conjugates indicates that increasing the number of covalent anchors systematically restricts the conformational ensemble, inducing a progressively more compact protein shell around nanoclusters. This structural rigidification at the interface directly translates into a 15‐fold enhancement of the Au‐NC near‐infrared photoluminescence and a six‐fold increase in its average lifetime. Our findings demonstrate that the conformational plasticity of IDPs and the capacity to engineer them can be harnessed as a molecular tuning knob, moving to a new regime of programmable soft‐matter control over the properties of quantum‐confined nanomaterials for tailored biotechnological applications.
KW - Fluorescence
KW - Custer
KW - Nano
KW - Advanced material
KW - Characterization
KW - Fluorescence quantum yield
KW - Integrating sphere spectroscopy
KW - Thiol ligands
KW - Gold
KW - Surface chemistry
KW - SWIR
KW - Mass spectrometry
KW - Protein
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655086
DO - https://doi.org/10.1002/chem.202502991
SN - 0947-6539
SP - 1
EP - 9
PB - Wiley VHC-Verlag
AN - OPUS4-65508
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gaal, Mate
A1 - Álvarez-Arenas, Tomás Gómez
T1 - Guest Editorial: Special Section on Air-Coupled Ultrasound
N2 - Air-coupled ultrasound is a challenging field dominated by the drastic impedance mismatch between air and all condensed matter, the low ultrasound velocity in the air, and the rapidly increasing attenuation with frequency.
The seven articles included in this special section showcase the diversity of current research on air-coupled ultrasound. All contributions in this special section are application-oriented, demonstrating the readiness of air-coupled ultrasound technologies to address real-world challenges. Whether it’s ensuring food safety, supporting heritage conservation, optimizing industrial inspection, or enabling in-field biological measurements, the practical relevance of these studies makes this section
particularly valuable for both researchers and industry professionals.
KW - Air-coupled ultrasound
KW - Transducers
KW - Non-destructive testing
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655041
DO - https://doi.org/10.1109/OJUFFC.2026.3656857
SN - 2694-0884
VL - 6
SP - 1
EP - 2
PB - Institute of Electrical and Electronics Engineers (IEEE)
AN - OPUS4-65504
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rastgou, Masoud
A1 - Hülagü, Deniz
A1 - Danilenko, Aleksandr
A1 - Manoocheri, Farshid
A1 - Hertwig, Andreas
A1 - Ikonen, Erkki
T1 - Comparison of thin-film thickness measurements using ellipsometry and reflectometry with uniform samples
N2 - This study evaluates spectroscopic ellipsometry and reflectometry using high-quality SiO2 and Al2O3 thin-films on Si substrates, thereby facilitating a detailed assessment of consistency of measurement results and uncertainty analyses. The results with detailed uncertainty budgets indicate good agreement between the two methods across a broad layer thickness range from 10 nm to 2000 nm, with deviations remaining well within the measurement uncertainties. Ellipsometry results have lower uncertainty than reflectometry results especially with the thinner layers, whereas reflectometry uncertainties are lower with the thickest layers studied. This work underscores the importance of rigorous thickness characterization and reliable uncertainty evaluation as critical factors in advancing both modeling and measurement practices in thin-film metrology.
KW - Ellipsometry
KW - Reflectometry
KW - Thin Film Metrology
KW - Measurement Accuracy
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655209
DO - https://doi.org/10.1088/1681-7575/ae3964
SN - 0026-1394
VL - 63
IS - 1
SP - 1
EP - 14
PB - IOP Publishing
CY - Bristol, UK
AN - OPUS4-65520
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bernardy, Christopher
A1 - Habib, Abdel Karim
A1 - zur Nedden, Philipp Maximilian
A1 - von Saldern, Jakob Georg Raimund
A1 - Beuth, Jan Paul
A1 - Orchini, Alessandro
T1 - Thermal Radiation Of Inclined Large Scale Hydrogen Jet Flames
N2 - In order to assess the thermal radiation emanating from hydrogen jet flames, experiments under real scale conditions were carried out at the Test Site Technical Safety of BAM. Herein, the behavior of inclined hydrogen jet flames was investigated. The aim of the work is to determine the Surface Emissive Power (SEP) and radiant heat fraction of these flames and to provide a reliable dataset for model evaluation purposes. Since the aforementioned values are not directly measurable, the incident heat radiation was measured at defined distances from the flame, as well as the flame’s shape and size. The required values were then derived from these measurements. The hydrogen releases ranged from 0.0125 kg/s to 0.175 kg/s with a 30 mm orifice. The mass flows were held constant during the releases, nevertheless a transient behavior of the flame could be observed since the experiments were carried out under open field conditions, with unsteady wind fields. In the literature, the flame lengths are often determined using visible light imaging, either by injecting coloring substances in the low light emitting hydrogen jet flame or by carrying out the measurements in darkness. In this work the jet flames were visualized using infrared (IR) and OH* imaging. The recorded flame shapes and resulting flame lengths are compared. Results from this showed that the flame lengths determined with OH* and IR recordings differ greatly. A flame length ratio lf OH*/lf IR in the range of 0.47–0.62 can be found. In addition, the SEP differ also in the range of 10 kW/m2–16 kW/m2 (IR) and 40 kW/m2–80 kW/m2 (OH*) for hydrogen jet flames due to differences in the determined flame surface. Conclusions regarding the determined xRAD values for IR and OH* result in approximately the same range of 0.031–0.043.
T2 - 11th Iinternational conference on hydrogen safety 2025
CY - Seoul, Republic of Korea
DA - 22.09.2025
KW - Hydrogen safety
KW - Jet flames
KW - Thermal radiation
KW - Large scale experiment
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655181
DO - https://doi.org/10.58895/hysafe.27
SN - 2943-5935
VL - 3
IS - 1
SP - 39
EP - 50
PB - Karlsruhe Institute of Technology Library
AN - OPUS4-65518
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kricheldorf, Hans R.
A1 - Weidner, Steffen
A1 - Meyer, Andreas
T1 - Poly(butylene terephthalate): About condensation, cyclization, degradation and elimination reactions in the solid state, and the role of smooth crystal surfaces
N2 - Three commercial poly(butylene terephthalate) (PBT) samples - Pocan B1300 (B13), Pocan B1600 (B16), and Addigy P 1210 (AP121) - served as the starting materials for the annealing experiments, which were conducted with and without the addition of esterification and transesterification catalysts. The catalysts used were Sn(II) 2-ethylhexanoate (SnOct₂), Zr(IV) acetylacetonate, and 4-toluene sulfonic acid (TSA). Temperatures varied between 150 and 210 °C. The PBT samples were characterized using differential scanning calorimetry (DSC), gel permeation chromatography (GPC), small-angle X-ray scattering (SAXS), and matrix-assisted laser desorption/ionization time-of-flight (MALDI TOF) mass spectrometry. The MALDI mass spectra of all three samples differed greatly but displayed mass peaks of cycles. Similar results were produced by annealing with SnOct₂ or Zr(acac)₄, which favored the formation of even-numbered cycles within the mass range below m/z 5000, along with slow degradation. TSA favored a more intensive degradation without the formation of cycles or even with the destruction of cycles. PBT chains with two carboxylic (COOH) end groups were the most stable species under all circumstances. The origin of the extremely high melting point of AP121 (241–242 °C) can be explained by the smoothing of crystallite surfaces via transesterification. The results suggest that combining MALDI mass spectrometry and SAXS measurements provides a new way to better understand the solid-state chemistry of PBT and related polyesters.
KW - MALDI-TOF MS
KW - Polybutylene Terephthalate
KW - Crystallization
KW - solid state
KW - cyclization
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-652844
DO - https://doi.org/10.1016/j.polymdegradstab.2025.111862
SN - 0141-3910
VL - 245
SP - 1
EP - 11
PB - Elsevier Ltd.
AN - OPUS4-65284
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dalgic, Mete‐Sungur
A1 - Kumar, Sourabh
A1 - Weidner, Steffen
T1 - Quantitative Analysis of Polymers by MALDI‐TOF Mass Spectrometry: Correlation Between Signal Intensity and Arm Number
N2 - The signal intensities of linear and star‐shaped poly(L‐lactides) (PLA) and poly (ethylene oxides) (PEO) were compared to determine the influence of the number of arms on the ionization in matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectrometry. In this study, a variety of blends were prepared and investigated, including binary and ternary combinations of linear and star‐shaped polymers with similar molecular masses. The focus was on examining their intensity ratios. In equimolar binary PLA blends, polymer stars were observed to exhibit higher intensities than their linear counterparts. This result was supported by experiments with equimolar ternary PLA blends, which clearly demonstrated an intensity dependence on the number of polymer arms. It was observed that four‐arm PLA exhibited higher intensities than three‐arm PLA. A similar trend was observed in investigations involving acetylated polymer end groups, suggesting that differences in ionization are primarily influenced by polymer architecture rather than end groups. In order to validate this assumption, the binding energies for [polymer‐K] + adduct ions utilizing the most stable geometry obtained from GOAT (Global Optimizer Algorithm) were calculated, revealing that star‐shaped lower mass oligomers have slightly higher binding energies.
KW - MALDI-TOF MS
KW - Starlike polymers
KW - Quantification
KW - Topology
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653401
DO - https://doi.org/10.1002/jms.70023
SN - 1076-5174
VL - 61
IS - 1
SP - 1
EP - 12
PB - John Wiley & Sons Ltd.
AN - OPUS4-65340
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Weidner, Steffen
A1 - Meyer, Andreas
A1 - Falkenhagen, Jana
A1 - Kricheldorf, Hans R.
T1 - Cyclic polyglycolide by means of metal acetylacetonates
N2 - Glycolide was polymerized in bulk at 160 °C using various metal acetylacetonates as catalysts. Zirconium acetylacetonate was particularly efficient, enabling rapid polymerization even at 130 °C. The formation of cyclic poly(glycolic acid) (PGA), most likely via a ring-expansion polymerization (REP) mechanism, was proven by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Depending on the polymerization conditions, the formation of even-numbered cycles was favored to varying degrees. Number-average molecular weights (Mn) in the range of 2000–3500 g mol−1 were achieved with dispersities below 2.0. Wide-angle X-ray scattering (WAXS) powder patterns showed that the crystal lattice was the same as that of known linear PGAs, regardless of the Mn values. These patterns enabled a comparison of crystallinities with values derived from DSC measurements.
KW - MALDI-TOF MS
KW - Polyglycolide
KW - Crystallization
KW - Small-angle X-ray scattering
KW - Cyclization
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653731
DO - https://doi.org/10.1039/d5ra07961f
SN - 2046-2069
VL - 16
IS - 2
SP - 1757
EP - 1764
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65373
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scharpmann, Philippa
A1 - Leonhardt, Robert
A1 - Schmidt, Anita
A1 - Kowal, Julia
A1 - Tichter, Tim
A1 - Krug von Nidda, Jonas
T1 - Exploring restrictive overdischarge cycling as a method to accelerate characteristic ageing in lithium-ion cells
N2 - This study presents a test protocol that greatly accelerates the ageing process of lithium-ion battery cells comprising a positive electrode of nickel manganese cobalt oxide while preserving their characteristic degradation upon cyclic ageing. Applying a repetitive restricted overdischarge, resulting in a depth of discharge larger than 100%, a capacity loss of 20% is achieved over five times faster compared to conventional cycling. The well-known overdischarge degradation phenomenon of copper current collector dissolution is deliberately prevented by setting a discharge cutoff voltage above the theoretical threshold of copper oxidation. Hence, the accelerated degradation can be primarily connected to solid electrolyte interphase growth.
A comparative assessment of the ageing dynamics using electrochemical impedance spectroscopy and differential voltage analysis hints towards similar, characteristic degradation processes during accelerated and conventional ageing. A post-ageing examination of the electrical behaviour (i.e., coulombic and energy efficiency, capacity fade) under reference conditions reveals very little to no lasting damages caused by
overdischarging. Additionally, post-mortem analysis discloses no increased copper dissolution when comparing cells subjected to accelerated and conventional ageing. Generally, the developed ageing method appears suitable for providing cells with a defined state of health at a reasonable timescale without altering the main degradation mechanisms significantly.
KW - Lithium-ion cell
KW - Accelerated ageing
KW - Overdischarge
KW - Degradation processes
KW - Differential voltage analysis
KW - Electrochemical impedance spectroscopy
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-650917
DO - https://doi.org/10.1016/j.jpowsour.2025.239072
SN - 0378-7753
VL - 665
SP - 1
EP - 9
PB - Elsevier B.V.
AN - OPUS4-65091
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hajhariri, Aliasghar
A1 - Eberwein, Robert
A1 - Camplese, Davide
A1 - Scarponi, Giordano Emrys
A1 - Cozzani, Valerio
A1 - Seidlitz, Holger
T1 - Cryogenic storage safety: Experimental evaluation of insulation under extreme conditions
N2 - Hydrogen is recognized as a keystone of the global energy transition, offering a clean, high-energy-density energy carrier ideal for storage and transportation. Among various storage options, liquid hydrogen (LH2) is especially advantageous for both mobile and stationary applications. However, ensuring the safety and performance of LH2 storage systems under extreme thermal conditions, such as fire exposure, remains an engineering challenge.
This study introduces an experimental framework, called the Cryogenic High-Temperature Thermal Vacuum Chamber (CHTTVC), designed to investigate the thermal-hydraulic response of vacuum-insulated cryogenic tanks under fire-like conditions. The apparatus enables evaluation of insulation performance, such as perlite and multilayer insulation (MLI), with a focus on thermal degradation, heat ingress, and vacuum stability.
Results indicate that combustible MLIs undergo substantial thermal degradation, leading to heat ingress rates of up to 6.5 kW and the formation of hazardous combustion by-products. In contrast, non-combustible MLIs and bulk insulation materials restrict heat ingress to approximately 3 kW while more effectively preserving vacuum integrity. Combustible MLIs also exhibit pronounced pressure increases in the evacuated section, reaching ∼6 × 104 Pa, nearly six times higher than those observed for non-combustible counterparts. Analysis of effective emissivity further reveals an enhancement in radiative heat transfer, approximately five times, for combustible MLIs following degradation. Additionally, marked thermal stratification develops under both nominal and extreme heat loads, with temperature gradients approaching 10 °C per 100 mm during sustained thermal exposure.
KW - Multi-Layer Insulation
KW - Cryogenic Storage
KW - Safety
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655380
DO - https://doi.org/10.1016/j.jlp.2026.105961
SN - 0950-4230
VL - 101
SP - 1
EP - 20
PB - Elsevier Ltd.
AN - OPUS4-65538
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pei, R.
A1 - Petrazoller, J.
A1 - Atila, Achraf
A1 - Arnoldi, S.
A1 - Xiao, L.
A1 - Liu, X.
A1 - Wang, H.
A1 - Korte-Kerzel, S.
A1 - Berbenni, S.
A1 - Richeton, T.
A1 - Guénolé, J.
A1 - Xie, Z.
A1 - Al-Samman, T.
T1 - Solute co-segregation mechanisms at low-angle grain boundaries in magnesium: A combined atomic-scale experimental and modeling study
N2 - Solute segregation at low-angle grain boundaries (LAGBs) critically affects the microstructure and mechanicalproperties of magnesium (Mg) alloys. In modern alloys containing multiple substitutional elements, understanding solute-solute interactions at microstructural defects becomes essential for alloy design. This study investigates the co-segregation mechanisms of calcium (Ca), zinc (Zn), and aluminum (Al) at a LAGB in a dilute Mg-0.23Al-1.00Zn-0.38Ca (AZX010) alloy by combining atomic-scale experimental and modeling techniques.Three-dimensional atom probe tomography (3D-APT) revealed significant segregation of Ca, Zn, and Al at the LAGB, with Ca forming linear segregation patterns along dislocation arrays characteristic of the LAGB. Clustering analysis showed increased Ca–Ca pairs at the boundary, indicating synergistic solute interactions.
Atomistic simulations and elastic dipole calculations demonstrated that larger Ca atoms prefer tensile regions around dislocations, while smaller Zn and Al atoms favor compressive areas. These simulations also found that Ca–Ca co-segregation near dislocation cores is energetically more favorable than other solute pairings, explaining the enhanced Ca clustering observed experimentally. Thermodynamic modeling incorporating calculated segregation energies and solute-solute interactions accurately predicted solute concentrations at the LAGB, aligning with experimental data. The findings emphasize the importance of solute interactionsat dislocation cores in Mg alloys, offering insights for improving mechanical performance through targeted alloying and grain boundary engineering.
KW - Atomic probe tomography
KW - Atomistic simulation
KW - Grain boundary
KW - Co-segregation
KW - Magnesium alloy
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655248
DO - https://doi.org/10.1016/j.actamat.2026.121947
SN - 1359-6454
VL - 306
SP - 1
EP - 13
PB - Elsevier Inc.
AN - OPUS4-65524
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rodricks, Carol Winnifred
A1 - Prockat, Annabell
A1 - Kalinka, Gerhard
A1 - Trappe, Volker
T1 - Novel Recyclable Hierarchical Carbon Fiber/Epoxy Composites: Preserving Fiber Length and Orientation Using Elium
N2 - Current recycling methods for polymer matrix composites produce short, unoriented carbon fibers, limiting their use to intermediate‐strength applications. A method is therefore needed to recycle fibers while preserving their original length and orientation, enabling a circular economy for carbon fiber composites. This study proposes a novel hierarchical composite designed to retain fiber length and orientation during recycling. Virgin carbon fibers are encased in an insoluble epoxy matrix to form tapes that act as the primary units of the structure. The primary tape matrix shields the fibers from chemical degradation while preserving their alignment throughout recycling. The tapes are then embedded in a secondary recyclable matrix, Elium, a thermoplastic polymer soluble in acetone with mechanical properties comparable to epoxy. The composite is recycled by dissolving the secondary Elium matrix in acetone and recovering the primary tape units with intact fiber length and orientation. The primary units can then be used to assemble new composites. In this study, hierarchical composite laminates underwent recycling up to three times. Their mechanical properties were assessed after each cycle. Laminates with an Elium secondary matrix retained 60%–90% of the mechanical performance of epoxy‐based laminates. Minimal degradation was observed between cycles, and fiber length, orientation, and volume fraction were fully preserved. Pushout tests confirmed that fibers in the primary tapes were sufficiently shielded during the recycling process. These results validate the feasibility of a hierarchical recyclable composite that combines recyclability with high mechanical performance, serving as a proof of concept and providing opportunities for future development.
KW - Review
KW - Interface
KW - Micromechanics
KW - Polymer matrix composites
KW - Glass fibre reinforced composites
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655276
DO - https://doi.org/10.1002/pc.70869
SN - 0272-8397
SP - 1
EP - 16
PB - Wiley Periodicals LLC.
AN - OPUS4-65527
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dixneit, J.
A1 - Gibmeier, J.
A1 - Kromm, Arne
A1 - Schubnell, J.
A1 - Lang, F.
A1 - Loebich, F.
A1 - Carl, E.-R.
A1 - Ya, W.
T1 - Residual stress distribution of a large component manufactured by AM-DED-Arc from high-strength weld filler material X90
N2 - Currently, DED-Arc manufactured components are not covered by design guidelines, and design factors such as residual stress factors are not defined for such components. This hinders industrial use, especially for components with a remaining surface waviness required by industry. For the first time the stress state of a high-strength, low-alloy, large-scale DED-Arc component was characterised in the as-built state and after cutting off the component from the substrate plate. Complementary methods of residual stress analyses were applied to gain a holistic insight into the residual stress distributions of a thick-walled part. In the as-built state, direction-dependent and position-dependent tensile residual stresses were found for the component at the level of the yield strength of the part. The additive manufacturing strategy continuous spiral deposition has no significant influence on the residual stresses in bead threshold area compared to the residual stresses of the remaining component. For this case, bead threshold is no structural imperfection. By removing the part from the substrate plate, the residual stresses are significantly redistributed. Tensile residual stresses are then present at a moderate level. Compressive residual stresses were determined in the volume of the deposited material. The general consideration of ‘‘high’’ tensile residual stresses in such thick-walled components is rather conservative. Therefore, design guidelines should take the manufacturing condition into account.
KW - AM-DED-Arc
KW - Residual stress
KW - High strength steel
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655239
DO - https://doi.org/10.1177/03093247251406876
SP - 1
EP - 18
PB - SAGE
AN - OPUS4-65523
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chaudhuri, Somsubhro
A1 - Krankenhagen, Rainer
A1 - Lapšanská, Ivana
A1 - Stamm, Michael
T1 - Modeling Temperature Responses of a Wind Turbine Blade Section Under Climate Chamber Conditions – Part 1: Challenges for FEM Simulations
N2 - The rapid expansion of wind energy infrastructure over the past 20–30 years has led up to a situation where advanced non‐destructive testing (NDT) technologies are the need‐of‐the‐hour, not only for new wind turbine blades (WTBs) that are being installed, but also for older infrastructure which is reaching their designed lifetime. NDT technologies that improve both the quality as well as reduce the time required for the inspection are sought after, and one such example is passive infrared thermography (IRT). For passive IRT to provide significant information/insight into the integrity of the WTB, there needs to exist certain thermal contrast to both visualize and distinguish between features in WTB. These features could be surface features, subsurface structure or defects. The temperature variations due to air temperature fluctuations and the sun assist (passively) to obtain the necessary thermal contrast. To better understand the thermal response of composite structures such as WTBs, a validation study was conducted using a WTB section subjected to controlled temperature transients within a climate chamber, without external irradiation. Infrared measurements were recorded using a thermographic camera, and the same specimen was modeled using finite element methods (FEM) in COMSOL Multiphysics. While a direct validation of the simulation is limited due to transient and unmeasured variables in the experimental data, qualitative comparison provides valuable insight into the applicability of FEM for predicting thermal behavior in passive IRT scenarios. This article represents the first part of a two‐part study, focusing on the FEM modeling approach and associated challenges. The second part will address the experimental investigation in more detail, with an emphasis on thermal contrast behavior under varied transient conditions.
KW - Finite element modeling
KW - Non- destructive testing
KW - Passive infrared thermography
KW - Thermal contrast
KW - Wind turbine blades
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655330
DO - https://doi.org/10.1002/we.70102
SN - 1095-4244
VL - 29
IS - 3
SP - 1
EP - 14
PB - Wiley
AN - OPUS4-65533
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Redda, Zinnabu Tassew
A1 - Prinz, Carsten
A1 - Yimam, Abubeker
A1 - Barz, Mirko
A1 - Becker, Katharina
A1 - Gizaw, Desta Getachew
A1 - Laß-Seyoum, Asnakech
T1 - Structural and textural characterization of Brassica carinata biochar to investigate its potential industrial applications
N2 - Biochar, a low-cost, and carbon-rich product of the thermal decomposition of biomass under oxygen-limited conditions and at relatively low temperatures, has recently been identified as a promising porous material with a wide range of industrial applications. In the present study, a comprehensive analysis of proximate, ultimate, nutrient profile, structural, and textural properties of a biochar derived from two Ethiopian indigenous Brassica carinata cultivars was conducted. The characterization of the biochar was achieved by employing a variety of well-established methods, including proximate analysis (moisture, volatile matter, ash content, and fixed carbon), ultimate analysis (C, S, and O content), atomic oxygen to carbon ratio (O/C), morphological and elemental composition analysis through scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS). Furthermore, a combination of mercury intrusion porosimetry (MIP), dynamic vapor sorption (DVS), and gas adsorption methods such as nitrogen and krypton gas adsorption, were used for an in-depth study of the porous structure. SEM morphological characterization showed that the biochar surfaces showed multiple pores of diverse sizes and shapes. EDS elemental composition analysis revealed that sodium, aluminium, and silicon were not detected, but potassium, calcium, magnesium, and iron were all present in noticeable amounts. Furthermore, ultimate analysis showed that the most prevalent elements were carbon (86 wt.%) and oxygen (10.41‒9.77 wt.%), while sulphur was present in negligible concentrations. MIP analysis demonstrated that the porosities of the biochars varied from 62.68 to 69.99 wt.%, with the Holetta-1 biochar showing the highest porosity. The superior porosity of Holetta-1, as confirmed via MIP analysis, yielded higher values for bulk volume (2.36 mL g− 1), skeletal volume (1.65 mL g− 1), and total intrusion volume (1.65 mL g− 1) compared to the Yellow Dodolla. The most frequent pore diameters were 172.46 μm for Yellow Dodolla and 111.42 μm for Holetta-1. The MIP log differential pore diameter distributions were observed to vary from 18 to 411 μm and 10 to 411 μm, respectively, for Yellow Dodolla and Holetta-1. Despite the biochars’ low specific surface areas (0.17–0.21 m² g⁻¹), krypton sorption was a suitable technique for its characterization compared to DVS and nitrogen sorption methods. In conclusion, the characterization studies confirmed that this carbon-rich porous material possesses unique and valuable properties, with these attributes position it as a promising alternative for diverse industrial applications, contributing to the development of a bio-based circular economy.
KW - Morphological characterization
KW - Mercury intrusion porosimetry
KW - Gas adsorption
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655325
DO - https://doi.org/10.1038/s41598-025-32063-1
SN - 2045-2322
VL - 16
IS - 1
SP - 1
EP - 19
PB - Springer Science and Business Media LLC
AN - OPUS4-65532
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stolar, Tomislav
A1 - Bayram, Dilara
A1 - May, Anastasia
A1 - Sundermann, Remie
A1 - Prinz, Carsten
A1 - Meyer, Klas
A1 - Myxa, Anett
A1 - Falkenhagen, Jana
A1 - Emmerling, Franziska
T1 - Selective mechanochemical conversion of post-consumer polyethylene terephthalate waste into hcp and fcu UiO-66 metal–organic frameworks
N2 - Single-use plastics strongly contribute to plastic pollution, and less than 10% of plastic waste is recycled globally. Here, we present a selective mechanochemical protocol for converting post-consumer polyethylene terephthalate (PET) transparent bottles and coloured textile waste into the porous metal–organic framework (MOF) UiO-66 materials. We used time-resolved in situ (TRIS) synchrotron powder X-ray diffraction and Raman spectroscopy to monitor the depolymerization of PET during ball milling. To convert disodium terephthalate to UiO-66, we developed base and base-free synthetic routes that lead to fcu and hcp UiO-66 phases, respectively, including the first ever synthesis of hcp UiO-66 by mechanochemistry. Our results demonstrate the potential of mechanochemistry to selectively access fcu and hcp UiO-66 phases using post-consumer PET waste.
KW - Mechanochemistry
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653958
DO - https://doi.org/10.1039/D4MR00126E
SN - 2976-8683
SP - 1
EP - 8
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65395
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chakraborty, Gouri
A1 - Das, Prasenjit
A1 - Bhattacharya, Biswajit
A1 - Prinz, Carsten
A1 - Emmerling, Franziska
A1 - Thomas, Arne
T1 - Room-temperature superprotonic conductivity in COOH-functionalized multicomponent covalent organic frameworks
N2 - In solid materials, the development of hydrogen bonding (H-bonding) networks within pores is crucial for efficient proton conductance. In this study, a chemically stable carboxylic acid-functionalized, quinoline-linked 2D microporous covalent organic framework (COF) (Qy-COOH) was synthesized using the Doebner multicomponent reaction (MCR) and compared to a similar framework lacking the –COOH functionality (Qy-H), prepared via an MC Domino reaction. The proton conductivity of the –COOH-functionalized MCR-COF was significantly enhanced, reaching 10−2 S cm−1, attributed to strong H-bonding interactions between water molecules and the dangling –COOH groups within the COF pores. In contrast, the analogous Qy-H framework exhibited a much lower proton conductivity of 10−5 S cm−1, while an imine-based COF showed only 10−6 S cm−1. This work represents the first demonstration of a general strategy to achieve efficient proton conduction in a class of layered 2D –COOH-functionalized COFs, offering superprotonic conductivity without requiring additives at room temperature. The MCR-COF design approach provides a promising pathway for developing highly stable and high-performance proton-conducting materials.
KW - Multicomponebt
KW - COF
KW - Proton Conductivity
KW - Superprotonic
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653526
DO - https://doi.org/10.1039/D5SC06953J
SN - 2041-6520
SP - 1
EP - 9
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-65352
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Appel, Paul Alexander
A1 - Prinz, Carsten
A1 - Low, Jian Liang
A1 - Asres, Nahom Enkubahri
A1 - Wu, Shu-Han
A1 - Freytag, Annica
A1 - Krug von Nidda, Jonas
A1 - de Sousa Amadeu, Nader
A1 - Fellinger, Tim-Patrick
T1 - Kern–Schale: Versiegelung nanoporöser Partikel mit semipermeablen Kohlenstoffschichten befreit Hartkohlenstoffanoden von ihrem Dilemma
N2 - In der vorliegenden Arbeit wird eine Kern-Schale-Strategie vorgestellt, die das grundlegende Problem gängiger nichtgraphitischer Hartkohlenstoff-Anoden adressiert: Hohe reversible Kapazitäten gehen bislang typischerweise mit erheblichen irreversiblen Verlusten in den ersten Zyklen einher. Analog zu Graphit, das sowohl Lithiumspeicherung als auch die Abtrennung von Elektrolytlösungsmitteln in einer homogenen Struktur vereint, zeigen wir, dass sich diese beiden Funktionen auch in nichtgraphitischen Kohlenstoffen gezielt in einer heterogenen Architektur kombinieren lassen. Hochporöse Aktivkohlen werden durch kinetisch kontrollierte Gasphasenabscheidung mit einer dünnen Schicht nichtgraphitischen Kohlenstoffs überzogen, sodass eine funktionale Kern-Schale-Struktur entsteht. Gasadsorptionsmessungen an Kern-, Schalen-, Kern-Schale- und mechanisch beschädigte Kern-Schale-Partikeln, bestätigen, dass die Porosität des Kerns erhalten bleibt und die Schale semipermeabel ist. Die Sorption von Diethylcarbonat wird als geeignetere Methode im Vergleich zu N2- oder CO2-Sorptionsmessungen eingeführt, um die irreversiblen Verluste des ersten Zyklus mit der tatsächlichen Flüssig-Fest-Grenzfläche von Kohlenstoffanoden zu verknüpfen. Die funktionalen Kern-Schale-Partikel zeigen eine stark reduzierte Aufnahme von Diethylcarbonat, was hohe reversible Kapazitäten bei deutlich geringeren Erstzyklusverlusten ermöglicht. Bei einer reversiblen Kapazität von 400 ± 24 mAh g−1 und einer initialen Coulombeffizienz von 82 ± 2% zeigt sich, dass die dreistufige Natriumspeicherung in der gezielt entwickelten Kern-Schale-Architektur den größeren Ionenradius von Natrium gegenüber Lithium (372 mAh g−1 in Graphit) kompensieren kann. Die entwickelten Kern-Schale-Anoden erreichen damit ein Leistungsniveau, das für eine kommerzielle Anwendung vielversprechend ist.
KW - Kern-Schale-Struktur
KW - Natriumionenbatterie
KW - Hartkohlenstoffanode
KW - Diethylcarbonatdampfsorption
KW - Aktivkohle
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655354
DO - https://doi.org/10.1002/ange.202519457
SN - 1521-3757
N1 - Es gibt eine parallele Sprachausgabe (englisch), ein Link befindet sich im Feld zugehöriger Identifikator - There is a parallel language edition (English), a link is in the field related identifier
SP - 1
EP - 10
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-65535
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Appel, Paul Alexander
A1 - Prinz, Carsten
A1 - Low, Jian Liang
A1 - Asres, Nahom Enkubahri
A1 - Wu, Shu-Han
A1 - Freytag, Annica
A1 - Krug von Nidda, Jonas
A1 - de Sousa Amadeu, Nader
A1 - Fellinger, Tim-Patrick
T1 - Core‐Shell: Resolving the Dilemma of Hard Carbon Anodes by Sealing Nanoporous Particles With Semi‐Permeable Coatings
N2 - A core-shell strategy is introduced to overcome the dilemma of common non-graphitic hard carbon anodes, linking high reversible storage capacity to practically unacceptable irreversible losses in the first cycle(s). Just as Graphite homogeneously combines effective lithium storage with an electrolyte solvent-sieving function, we show that both of these functions could be strategically integrated into non-graphitic carbons in a heterogeneous structure. Highly porous activated carbons are sealed by kinetically tuned gas-phase deposition of non-graphitic carbon to form a functional core-shell structure. Gas sorption porosimetry on core, shell, core–shell, and cracked core-shell particles confirms preserved core porosity and a semi-permeable shell. Diethyl carbonate sorption analysis is introduced as a more suitable probe than N2 or CO2 sorption, linking first-cycle losses to the liquid–solid interface of carbon anodes. The functional core-shell particles with much reduced diethyl carbonate uptake allow for high storage capacity and reduced first cycle losses. Delivering 400 ± 24 mAh g−1 with 82 ± 2% first-cycle reversibility, it is shown that three-stage Na storage in designed core-shell anodes can compensate for the larger size of sodium compared to lithium stored in graphite anodes (372 mAh g−1). The designed core-shell anodes show state-of-the-art performance with commercial promise.
KW - Sodium-ion battery
KW - Activated carbon
KW - Core-shell
KW - Hard carbon anode
KW - Diethyl carbonate vapor sorption
PY - 2026
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655346
DO - https://doi.org/10.1002/anie.202519457
SN - 1433-7851
N1 - Es gibt eine parallele Sprachausgabe (deutsch), ein Link befindet sich im Feld zugehöriger Identifikator - There is a parallel language edition (German), a link is in the field related identifier
SP - 1
EP - 9
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-65534
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Simon, Fabian
A1 - von der Au, Marcus
A1 - Gehrenkemper, Lennart
A1 - Meermann, Björn
T1 - An optimized method for PFAS analysis using HR–CS–GFMAS via GaF detection
N2 - The analysis of per- and polyfluoroalkyl substances (PFAS) via sum parameters like extractable organic fluorine (EOF) in combination with high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR–CS–GFMAS) is highly promising regarding fluorine sensitivity and selectivity. However, the HR–CS–GFMAS method includes several drying and heating steps which can lead to losses of volatile PFAS before the molecular formation step using e.g., GaF formation. Hence, the method leads to a strong discrimination of PFAS within the EOF depending on their physical/chemical properties and is therefore associated with reduced accuracy. To reduce this discrepancy and to indicate realistic PFAS pollution values, an optimization of the HR–CS–GFMAS method for PFAS analysis is needed. Hence, we determined fluorine response factors of several PFAS with different physical/chemical properties upon application of systematic optimization steps. We could therefore improve the method's sensitivity for PFAS analysis using a modifier drying pre-treatment step followed by a sequential injection of sample solutions. The highest improvement in sensitivity of volatile PFAS was shown upon addition of a Mg modifier during drying pre-treatment. Thereby, during optimization the relative standard deviation of fluorine response factors could be reduced from 55 % (initial method) to 27 % (optimized method) leading to a more accurate determination of organofluorine sum parameters. The method provides an instrumental LOD and LOQ of β(F) 1.71 μg/L and 5.13 μg/L, respectively. Further validation aimed to investigate several matrix effects with respect to water matrices. Here, substance-specific behavior was observed. For example, perfluorooctanoic acid (PFOA) which was used as calibrator, showed signal suppressions upon high chloride concentrations (>50 mg/L). Hence, a thorough separation of Cl from analytes during sample preparation is needed for accurate sum parameter analysis.
KW - PFAS
KW - GF-AAS
KW - Method optimization
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610522
DO - https://doi.org/10.1016/j.talanta.2024.126811
VL - 281
SP - 1
EP - 11
PB - Elsevier B.V.
AN - OPUS4-61052
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lu, Xin
A1 - Krebber, Katerina
T1 - Suppression of Rayleigh fading induced errors in φOTDR by different pulse widths for improving the reliability of civil infrastructure monitoring
N2 - Rayleigh fading is a widely observed phenomenon in the many fields, such as wireless communication and optical imaging. It is also the main factor limiting the performance of the phase-sensitive optical time domain reflectometry (φOTDR). The low SNR at the fading points results in a large measurement error, severely affecting the reliability of civil infrastructure monitoring. The proposed method involves changing the pulse width during measurements to suppress the impact of fading. Experimental result shows that the number of fading points is greatly reduced by ∼ 96 % and the measurement error is reduced by more than 5 times. Unlike existing methods, this approach requires no hardware modifications, making it applicable to almost all current phase-based φOTDR systems. The versatility and effectiveness of this method make it an excellent candidate for infrastructure monitoring and related fields.
KW - Distributed fiber sensing
KW - Optical fiber sensing
KW - Phase-sensitive optical time domain reflectometry
KW - Infrastructure monitoring
KW - Rayleigh fading
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614208
DO - https://doi.org/10.1016/j.optlastec.2024.111927
SN - 1879-2545
VL - 181
SP - 1
EP - 9
PB - Elsevier Ltd.
AN - OPUS4-61420
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Krone, David
A1 - Esche, Erik
A1 - Skiborowski, Mirko
A1 - Repke, Jens-Uwe
T1 - Optimization-based process synthesis by phenomena-based building blocks and an MINLP framework featuring structural screening
N2 - An existing approach for optimization-based process synthesis with abstracted phenomena-based building blocks (PBB) is extended by implementing it into a novel MINLP framework with structural screening. Consistency across the multilayer MINLP framework is guaranteed by creating a MathML/XML data model and subsequently exporting the code to the different program parts. The novel framework focuses both on fidelity by implementing thermodynamically sound models and on generality by employing a state-space superstructure that spans a large search space. In order to retain tractability, we insert a structural screening layer which prescreens based on binary decision variables of the superstructure by graph- and rule-based analyses, penalizing non-physical instances without solution of the underlying MINLP. The MINLP framework is successfully applied on two challenging synthesis tasks to determine the separation of the feed streams of benzene and toluene, as well as of n-pentane, n-hexane, and n-heptane utilizing superstructures with two, respectively four PBB.
KW - Process synthesis
KW - Superstructure optimization
KW - Distillation
KW - Mathematical programming
KW - Structural screening
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621955
DO - https://doi.org/10.1016/j.compchemeng.2024.108955
VL - 194
SP - 1
EP - 19
PB - Elsevier Ltd.
AN - OPUS4-62195
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kärcher, Victor
A1 - Reiker, Tobias
A1 - da Costa, Pedro F.G.M.
A1 - de Camargo, Andrea S.S.
A1 - Zacharias, Helmut
T1 - Quantum control in size selected semiconductor quantum dot thin films
N2 - We introduce a novel technique for coherent control that employs resonant internally generated fields in CdTe quantum dot (QD) thin films at the L-point. The bulk band gap of CdTe at the L-point amounts to 3.6 eV, with the transition marked by strong Coulomb coupling. Third harmonic generation (λ3 = 343 nm, hν = 3.61 eV) for a fundamental wavelength of λ 1 = 1,030 nm is used to control quantum interference of three-photon resonant paths between the valence and conduction bands. Different thicknesses of the CdTe QDs are used to manipulate the phase relationship between the external fundamental and the internally generated third harmonic, resulting in either suppression or strong enhancement of the resonant third harmonic, while the nonresonant components remain nearly constant. This development could pave the way for new quantum interference–based applications in ultrafast switching of nanophotonic devices.
KW - Nonlinear nanophotonics
KW - Quantum interference
KW - Third harmonic
KW - Coherent control
KW - Thin films
KW - Quantum dots
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625859
DO - https://doi.org/10.1515/nanoph-2024-0529
VL - 14
IS - 2
SP - 229
EP - 239
PB - Walter de Gruyter GmbH
AN - OPUS4-62585
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Arai, Marylyn Setsuko
A1 - Ravaro, Leandro Piaggi
A1 - Brambilla, Gabriel
A1 - Maia, Lauro June Queiroz
A1 - Reza Dousti, Mohammad
A1 - de Camargo, Andrea Simone Stucchi
T1 - Upconverting Nanoparticles and Cu(I) Complex-Based Platform for Oxygen Sensing, Thermometry, and Emission Color Tuning
N2 - Multifunctional nanoplatforms combine different material properties to meet a wide range of applications, allowing highly customizable systems. In this rapidly advancing research field, we introduce a multifunctional nanomaterial based on the synergy between Tm3+-doped upconverting nanoparticles (UCNPs) and a Cu(I) complex (CuCom). This material is designed for oxygen sensing, optical thermometry, and emission color tuning. In various concentrations, the CuCom complex was electrostatically integrated into a mesoporous silica shell surrounding the core UCNPs (UCNP@mSiO2). The optimized system, UCNP@mSiO2@CuCom-10, was evaluated for different applications. Due to the spectral overlap between the CuCom absorption and the nanoparticles emission, excitation at 980 nm allows most of the UV-blue emission output from the UCNPs to be transferred to the CuCom via luminescent resonance energy transfer (LRET), producing red emission from the molecule. The remaining Tm3+ emission enables optical thermometry, while CuCom’s sensitivity to molecular oxygen supports its application in gas sensing. In upconversion mode, the nanoplatform achieved a Stern−Volmer constant for O2 sensing of 1.64 and demonstrated thermometric relative sensitivities of 0.9% and 1% K−1 at room temperature, with a linear response from 193 to 373 K. Additionally, the emission color of UCNP@mSiO2@CuCom-10 can be tuned from blue to white and yellow, by varying the excitation and temperature, adding further functionality to the system. This multifunctional platform suggests promising applications in biology, medicine, and environmental monitoring.
KW - M
KW - O2 sensing
KW - Upconversion
KW - Luminescence resonance energy transfer (LRET)
KW - Optical thermometry
KW - Mesoporous silica shell
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625869
SN - 2574-0970
DO - https://doi.org/10.1021/acsanm.4c06351
VL - 8
SP - 854
EP - 862
PB - American Chemical Society (ACS)
AN - OPUS4-62586
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Valentini, Martino
A1 - De Almeida, Olivier
A1 - Kakkonen, Markus
A1 - Kalinka, Gerhard
A1 - Dorigato, Andrea
A1 - Kallio, Pasi
A1 - Fredi, Giulia
T1 - Effect of fiber surface state on the thermomechanical and interfacial properties of in situ polymerized polyamide 6/basalt fiber composites
N2 - This study investigates the thermomechanical properties and interfacial adhesion of novel in-situ polymerized anionic polyamide 6 (aPA6) composites reinforced with basalt fibers (BF). The impact of different BF surface states - as-received (BFa), ethanol-washed (BFw), and thermally desized (BFu) on composite performance is examined through a comprehensive approach. For the first time, anionic PA6/BF composites with very low residual monomer content were successfully produced via thermoplastic resin transfer molding (tRTM). The PA6/BFw composites exhibited the highest interlaminar/interfacial shear strength in short beam shear test (52 ±8 MPa) and fiber push out test (34 ± 11 MPa) tests. Fiber microdebonding test, performed only on PA6/BFw, yielded a low interfacial shear strength (12 ± 4 MPa), which was attributed to droplet porosity resulting from concurrent polymerization and crystallization. Thermal desizing significantly deteriorated interfacial strength (19.6 ± 1.2 MPa in short beam shear test). This multi-technique characterization provides insights into optimizing the fiber–matrix adhesion in these advanced thermoplastic composites.
KW - Anionic Polyamide 6
KW - Reactive thermoplastics
KW - Basalt fibers
KW - Microdebonding
KW - Fiber push out
KW - Short beam shear test
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623596
DO - https://doi.org/10.1016/j.compositesa.2024.108681
SN - 1878-5840
VL - 190
SP - 1
EP - 15
PB - Elsevier Ltd.
CY - Niederlande
AN - OPUS4-62359
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kozachynskyi, Volodymyr
A1 - Hoffmann, Christian
A1 - Esche, Erik
T1 - Why fixing alpha in the NRTL model might be a bad idea – Identifiability analysis of binary vapor-liquid equilibria
N2 - New vapor-liquid equilibrium (VLE) data are continuously being measured and new parameter values, e.g., for the nonrandom two-liquid (NRTL) model are estimated and published. The parameter α, the nonrandomness parameter of NRTL, is often not estimated but is heuristically fixed to a constant value based on the involved components. This can be seen as a manual application of a (subset selection) regularization method. In this work, the practical parameter identifiability of the NRTL model for describing the VLE is analyzed. It is shown that fixing α is not always a good decision and sometimes leads to worse prediction properties of the final parameter estimates. Popular regularization techniques are compared and Generalized Orthogonalization is proposed as an alternative to this heuristic. In addition, the sequential Optimal Experimental Design and Parameter Estimation (sOED-PE) method is applied to study the influence of the regularization methods on the performance of the sOED-PE loop.
KW - NRTL
KW - VLE
KW - Nonlinear programming
KW - Model-based optimal experimental design
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623605
DO - https://doi.org/10.1016/j.ces.2024.121122
VL - 305
SP - 1
EP - 18
PB - Elsevier Ltd.
AN - OPUS4-62360
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cunningham, Patrick
A1 - Wang, L.
A1 - Kane, S.
A1 - Kim, A.
A1 - Jenkins, B. M.
A1 - Miller, S. A.
T1 - Lifecycle implications and mechanical properties of carbonated biomass ashes as carbon-storing supplementary cementitious materials
N2 - Methods to sequester and store atmospheric CO2 are critical to combat climate change. Alkaline-rich bioashes are potential carbon fixing materials. This work investigates potential co-benefits from mineralizing carbon in biomass ashes and partially replacing high embodied greenhouse gas (GHG) Portland cement (PC) in cement-based materials with these ashes. Specifically, rice hull ash (RHA), wheat straw ash (WSA), and sugarcane bagasse ash (SBA) were treated to mineralize carbon, and their experimental carbon content was compared to modeled potential carbonation. To understand changes in the cement-based storage materials, mortars made with CO2-treated WSA and RHA were experimentally compared to PC-only mortars and mortars made with ashes without prior CO2 treatment. Life cycle assessment methodology was applied to understand potential reductions in GHG emissions. The modeled carbonation was ∼18 g-CO2/kg-RHA and ∼180 g-CO2/kg-WSA. Ashes oxidized at 500 °C had the largest measured carbon content (5.4 g-carbon/kg-RHA and 35.3 g-carbon/kg-WSA). This carbon appeared to be predominantly residual from the biomass. Isothermal calorimetry showed RHA-PC pastes had similar heat of hydration to PC-pastes, while WSA-PC pastes exhibited an early (at ∼1.5 min) endothermic dip. Mortars with 5 % and 15 % RHA replacement had 1–12 % higher compressive strength at 28 days than PC-only mortars, and milled WSA mortars with 5 % replacement had 3 % higher strength. A loss in strength was noted for the milled 15 % WSA, the CO2-treated 5 %, and the 15 % WSA mortars. Modeled reductions in GHG emissions from CO2-treated ashes were, however, marginal (<1 %) relative to the untreated ashes.
KW - CO2 sequestration
KW - CO2 storage
KW - Biomass ash
KW - Supplementary cementitious materials
KW - Concrete
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626959
DO - https://doi.org/10.1016/j.biombioe.2025.107772
SN - 1873-2909
VL - 197
SP - 1
EP - 13
PB - Elsevier
CY - Amsterdam
AN - OPUS4-62695
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bosc-Bierne, Gaby
A1 - Weller, Michael G.
T1 - Investigation of impurities in peptide pools
T1 - Untersuchung von Verunreinigungen in Peptidpools
N2 - Peptide pools are important research tools in different biomedical fields. They consist of a complex mixture of defined peptides, which places high demands on the production and quality control of these products. Previously it has been shown that the combination of UHPLC with high-resolution mass-spectrometry (HRMS) is a fast and powerful method to confirm the relative concentration and the structural identity of all peptides expected to be in the pool. In this work, the additional information contained in the UV chromatograms and mass spectra is used to search for impurities due to synthesis by-products and degradation during storage and transportation and to identify possible analytical artifacts. It was shown that most impurities are only present in trace amounts and can be considered uncritical for most applications. The most frequent and perhaps unexpected impurities were homo- and heterodimers caused by the free cysteines contained in these peptide pools. Furthermore, pyroglutamate and aspartimide formation, deamidation, methionine oxidation, and amino acid deletions could be found. This list is not intended to be comprehensive, but rather a brief guide to quickly identify impurities and, in the long term, to suggest possible changes in the composition of the peptide pools to avoid such impurities by design or by special precautions.
N2 - Peptidpools sind wichtige Forschungsinstrumente in verschiedenen biomedizinischen Bereichen. Sie bestehen aus einer komplexen Mischung definierter Peptide, was hohe Anforderungen an die Herstellung und Qualitätskontrolle dieser Produkte stellt. In der Vergangenheit wurde gezeigt, dass die Kombination von UHPLC mit hochauflösender Massenspektrometrie (HRMS) eine schnelle und leistungsfähige Methode zur Bestätigung der relativen Konzentration und der strukturellen Identität aller Peptide ist, die in dem Pool erwartet werden. In dieser Arbeit werden die zusätzlichen Informationen, die in den UV-Chromatogrammen und Massenspektren enthalten sind, genutzt, um nach Verunreinigungen zu suchen, die auf Nebenprodukte der Synthese und den Abbau während der Lagerung und des Transports zurückzuführen sind, und um mögliche analytische Artefakte zu identifizieren. Es hat sich gezeigt, dass die meisten Verunreinigungen nur in Spuren vorhanden sind und für die meisten Anwendungen als unkritisch angesehen werden können. Die häufigsten und vielleicht unerwartetsten Verunreinigungen waren Homo- und Heterodimere, die durch die in diesen Peptidpools enthaltenen freien Cysteine verursacht werden. Außerdem wurden Pyroglutamat- und Aspartimidbildung, Deamidierung, Methioninoxidation und Aminosäuredeletionen festgestellt. Diese Liste erhebt keinen Anspruch auf Vollständigkeit, sondern ist eher ein kurzer Leitfaden, um Verunreinigungen schnell zu identifizieren und langfristig mögliche Änderungen in der Zusammensetzung der Peptidpools vorzuschlagen, um solche Verunreinigungen durch Design oder besondere Vorsichtsmaßnahmen zu vermeiden.
KW - Synthetic peptides
KW - Degradation
KW - Synthetic artifacts
KW - Peptide losses
KW - Stability of peptides
KW - Disulfide dimers
KW - Cysteine dimers
KW - Isomers
KW - Cysteine alkylation
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626987
DO - https://doi.org/10.3390/separations12020036
SN - 2297-8739
VL - 12
IS - 2
SP - 1
EP - 18
PB - MDPI AG
CY - Basel
AN - OPUS4-62698
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Asante, Bright
T1 - Optimized mix design and fire resistance of geopolymer recycled aggregate concrete under elevated temperatures
N2 - This study investigates the performance of fly ash-based geopolymer recycled aggregate concrete (GRAC) as a sustainable alternative to Ordinary Portland Cement (OPC) concrete, focusing on its compressive strength and behavior under high-temperature exposure (150 ◦C, 300 ◦C, 600 ◦C, and 900 ◦C). The research emphasizes the use of 100 % recycled concrete aggregates as a replacement for natural aggregates, with samples cured at ambient conditions and at 60 ◦C in an oven. Key factors, including water content and curing conditions, were evaluated to determine their influence on compressive strength and thermal stability. Results indicate that water content is the primary factor governing compressive strength, while recycled aggregates contribute to a secondary but notable effect. GRAC maintained up to 65 % of its initial strength after exposure to 600 ◦C, though strength degradation and severe cracking occurred at 900 ◦C. Oven-cured samples showed fewer surface cracks but experienced slightly higher mass loss than room-cured coun-terparts. This study highlights the potential of GRAC as an environmentally friendly material capable of withstanding moderate thermal conditions, providing significant contributions to green construction practices and the reuse of construction and demolition waste.
KW - Geopolymer
KW - Recycled aggregate concrete
KW - Elevated temperature
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627071
DO - https://doi.org/10.1016/j.cscm.2025.e04401
SN - 2214-5095
VL - 22
SP - 1
EP - 17
PB - Elsevier Ltd.
AN - OPUS4-62707
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Reigl, Selina
A1 - Van Driessche, Alexander
A1 - Stawski, Tomasz
A1 - Koltzenburg, Sebastian
A1 - Kunz, Werner
A1 - Kellermeier, Matthias
T1 - Sustainable Pathways for the Synthesis of Calcium Sulfate Hemihydrate
N2 - Calcium sulfate, and especially its hemihydrate form (bassanite), is crucial in the construction industry, primarily used as a hydraulic binder in cements, mortars, and wallboards. Because of the rapid transformation of bassanite into thermodynamically stable gypsum (calcium sulfate dihydrate) upon contact with water, natural deposits are scarce, rendering it one of the most extensively produced inorganic materials worldwide. Currently, bassanite is derived from mined or waste gypsum through a thermal dehydration process, which is energy-intensive and costly. As sustainability has become a key target for industrial processes and products, a series of studies aiming to increase the energy efficiency and reduce the carbon footprint of bassanite production was published recently. Two primary approaches are pursued: conversion of gypsum and direct precipitation of bassanite from solution. In both cases, organic solvents, (specific) additives and/or elevated temperatures have been used to control the activity/availability of water in the reaction medium and thus direct phase selection towards bassanite. This review offers a comprehensive overview of alternative bassanite production methods, critically examining their benefits, potential downsides, and overall impact on
the sustainability of industrial-scale use.
KW - Calcium sulfate
KW - Gypsum
KW - Bassanite
KW - Recycling
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630657
DO - https://doi.org/10.1002/anie.202415161
SN - 1521-3773
SP - 1
EP - 20
PB - Wiley VHC-Verlag
AN - OPUS4-63065
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zöllner, Moritz T.
A1 - Dariz, Petra
A1 - Riedel, Jens
A1 - Schmid, Thomas
T1 - Dolomite and Mg Calcite as Mineral Thermometers in Mortar Binders. A High Resolution Raman Spectroscopic Study
N2 - This paper suggests the use of high‐resolution Raman scattering bands of MgCa carbonates as posteriori thermometer minerals in archaeometric studies. Therefore, the thermal behavior of two dolomite samples and the hydration and carbonation reaction in air of the decomposition products were investigated by Raman microspectroscopy. The increase in the calcination temperature resulted in the formation of – Raman silent MgO and – inert Mg calcite at 700°C–750°C. In contrast, the decarbonation, hydration, and recarbonation of sample material exposed to 750°C–900°C in a muffle furnace led to the appearance of Mg‐free calcite. High spectral resolution Raman spectroscopy enabled a spectral distinction between these two groups due to differences in the band parameters (peak position, bandwidth) of the vibrational (v1, v4, L) modes of calcite. In combination with Raman microspectroscopic mapping, this spectral information represents a new approach for the estimation of burning temperatures of medieval high‐fired gypsum mortars via natural dolomite impurities. Thus, the results of this work highlight the importance and potential of Raman microspectroscopy as a thermometric tool for elucidating the thermal history of anthropogenic fired materials, with potential applications for archaeometry and art technology, as well as for quality controls in the frame of the production of mineral mortar binders and ceramics or bricks, respectively.
KW - Mineral thermometry
KW - Raman spectroscopy
KW - Dolomite
KW - High-fired gypsum mortar
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630270
DO - https://doi.org/10.1002/jrs.6810
SN - 1097-4555
SP - 1
EP - 13
PB - Wiley
AN - OPUS4-63027
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Liehr, Alexander
A1 - Dingel, Kristina
A1 - Kottke, Daniel
A1 - Degener, Sebastian
A1 - Meier, David
A1 - Sick, Bernhard
A1 - Niendorf, Thomas
T1 - Data selection strategies for minimizing measurement time in materials characterization
N2 - Every new material needs to be assessed and qualified for an envisaged application. A steadily increasing number of new alloys, designed to address challenges in terms of reliability and sustainability, poses significant demands on well-known analysis methods in terms of their efficiency, e.g., in X-ray diffraction analysis. Particularly in laboratory measurements, where the intensities in diffraction experiments tend to be low, a possibility to adapt the exposure time to the prevailing boundary conditions, i.e., the investigated microstructure, is seen to be a very effective approach. The counting time is decisive for, e.g., complex texture, phase, and residual stress measurements. Traditionally, more measurement points and, thus, longer data collection times lead to more accurate information. Here, too short counting times result in poor signal-to-background ratios and dominant signal noise, respectively, rendering subsequent evaluation more difficult or even impossible. Then, it is necessary to repeat experiments with adjusted, usually significantly longer counting time. To prevent redundant measurements, it is state-of-the-art to always consider the entire measurement range, regardless of whether the investigated points are relevant and contribute to the subsequent materials characterization, respectively. Obviously, this kind of approach is extremely time-consuming and, eventually, not efficient. The present study highlights that specific selection strategies, taking into account the prevailing microstructure of the alloy in focus, can decrease counting times in X-ray energy dispersive diffraction experiments without any detrimental effect on data quality for the subsequent analysis. All relevant data, including the code, are carefully assessed and will be the basis for a widely adapted strategy enabling efficient measurements not only in lab environments but also in large-scale facilities.
KW - Materials characterization
KW - Machine learning
KW - X-ray diffraction
KW - Measurement optimization
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630831
DO - https://doi.org/10.1038/s41598-025-96221-1
SN - 2045-2322
VL - 15
IS - 1
SP - 1
EP - 12
PB - Springer Science and Business Media LLC
AN - OPUS4-63083
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Strauß, Lea
A1 - Duarte, Larissa
A1 - Kruse, Julius
A1 - Madia, Mauro
A1 - Löwisch, Günther
T1 - An equivalent stress approach for predicting fatigue behavior of additively manufactured AlSi10Mg
N2 - Laser-based powder bed fusion (PBF-LB) is an advanced additive manufacturing technique renowned for its precision and capability to fabricate complex metal components. However, the high thermal gradients and rapid cooling rates intrinsic to this process introduce significant process-induced effects, such as inhomogeneities, surface roughness, anisotropy, and residual stress, all of which critically influence the fatigue behavior of the produced parts. This study investigates the fatigue performance of AlSi10Mg samples produced by PBF-LB, examining the impact of varying surface conditions, geometries, and residual stress levels. Fatigue-life prediction models are formulated based on nominal stress amplitude, residual stress, form factor, crack-initiating inhomogeneity, and surface roughness, with smooth samples serving as a baseline reference. The study presents two empirical models for predicting fatigue life and fatigue strength using S–N curves and the Kitagawa–Takahashi diagram with the El Haddad approach, derived from comprehensive experimental data, including finite element modeling, fatigue-life measurements, surface roughness evaluations, and residual stress analysis.
KW - AlSi10Mg
KW - Kitagawa–Takahashi diagram
KW - El Haddad
KW - Equivalent stress
KW - Fatigue-life prediction
KW - PBF-LB/M
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625176
DO - https://doi.org/10.1007/s40964-025-00974-0
SP - 1
EP - 16
PB - Springer Science and Business Media LLC
AN - OPUS4-62517
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Omar, Hassan
A1 - Ahmadi, Shayan
A1 - Szymoniak, Paulina
A1 - Schönhals, Andreas
T1 - Molecular Mobility of Thin Films of Poly (bisphenol-A carbonate) Capped and with one Free Surface: From Bulk-like Samples down to the Adsorbed Layer
N2 - The molecular mobility of thin films of poly(bisphenol A carbonate) (PBAC) was systematically investigated using broadband dielectric spectroscopy, employing two distinct electrode configurations. First, films were prepared in a capped geometry between aluminum electrodes employing a crossed electrode capacitor (CEC) configuration, down to film thicknesses of 40 nm. The Vogel temperature, derived from the temperature dependence of relaxation rate of the α-relaxation, increases with decreasing film thickness characterized by an onset thickness. The onset thickness depends on the annealing conditions, with less intense annealing yielding a lower onset thickness. Additionally, a broadening of the β-relaxation peak was observed with decreasing thickness, attributed to the interaction of phenyl groups with thermally evaporated aluminum, resulting in a shift of certain relaxation modes to higher temperatures relative to the bulk material. A novel phenomenon, termed the slow Arrhenius process (SAP), was also identified in proximity to the α-relaxation temperature.
For films with thicknesses below 40 nm, nanostructured electrodes (NSE) were utilized, incorporating nanostructured silica spacers to establish a free surface with air. This free surface causes an enhancement in the molecular mobility for the 40 nm sample, preserving the β-relaxation as a distinct peak. The α-relaxation was detectable in the dielectric loss down to 18 nm, shifting to higher temperatures as film thickness is decreased. Notably, the onset thickness for the increase in Vogel temperature was lower in the NSE configuration compared to the CEC setup, attributed to the presence of the polymer-air interface.
KW - Thin polymer films
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623422
DO - https://doi.org/10.1039/d4sm01238k
SN - 1744-6848
VL - 21
IS - 2
SP - 241
EP - 254
PB - RSC
AN - OPUS4-62342
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Liao, Chun-Man
ED - Zhang, Jian
T1 - Modal and Wave Propagation Analysis of Vibration Tests on a Laboratory Building Model Before and After Damage
N2 - Weakened structural stiffness is often a consequence of building damage, particularly after severe events such as earthquakes, where compromised structural performance can pose significant risks. To prevent immediate structural failure, an early warning system is essential, which requires inspection of local components. This research aims to achieve that by exploring the wave propagation analysis method, specifically seismic interferometry. Previous studies have applied this method to building structures, treating them as homogeneous layers of grouped floors. By analyzing the wave travel time along the height of these layers, the fundamental period of the building was estimated. However, this approach did not account for local damage or the variability of structural components, similar to the limitations of vibration‐based damage detection methods, which mainly identify global changes. Thus, the goal of this paper is to improve structural health monitoring by examining the sensitivity of wave screening, bridging the gap between nondestructive testing and vibration‐based damage detection. A half‐scale, seven‐story building model, characterized by vertical stiffness irregularity and transverse plan asymmetry, was tested in a laboratory setting. Two vertical sensor arrays were placed near corner columns of different sizes, representing both strong and weak structural areas. These arrays recorded floor accelerations in three directions. The study confirmed the effectiveness of wave propagation analysis for detecting damage along the sensor arrays before and after the earthquake. A transmissibility damage indicator was used to correlate changes in wave velocity, providing a quantitative assessment of damage levels along the wave propagation path.
KW - Damage location
KW - Laboratory test
KW - Soft story
KW - Stifness irregular structure
KW - Structural health monitoring
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624931
DO - https://doi.org/10.1155/stc/3453150
SN - 1545-2263
VL - 2025
IS - 1
SP - 1
EP - 17
PB - John Wiley & Sons Ltd.
AN - OPUS4-62493
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nagel, Thomas
A1 - Rühaak, Wolfram
A1 - Amann, Florian
A1 - Bracke, Guido
A1 - Buske, Stefan
A1 - Kowalski, Julia
A1 - Reiche, Sönke
A1 - Schäfer, Thorsten
A1 - Scheytt, Traugott
A1 - Stumpf, Thorsten
A1 - Völzke, Holger
A1 - Wellmann, Florian
A1 - Kolditz, Olaf
T1 - Deep geological disposal - Editorial to the topical collection
N2 - The subsurface geological environment, historically a key source of fossil and mineral resources, has seen a significant broadening of its potential applications in recent years, with increasing emphasis on its use for energy production and storage.
A critical factor in utilizing subsurface space is ensuring the sustainability of management practices, with particular attention to the potential environmental impacts that may result.
The current Topical Collection on Deep Geological Disposal places greater emphasis on the geotechnical aspects of geological disposal, with a particular focus on the safe isolation of hazardous materials, including radioactive waste. The Topical Collection on Deep Geological Disposal covers both experimental (laboratory and in-situ) and theoretical studies of various geotechnical applications, such as geological disposal of radioactive or other materials, e.g. coal-based solid waste, carbon dioxide sequestration in fractured reservoirs, and brine solutions, but also aspects of uranium mining.
The articles in the Topical Collections are arranged under
the following headings:
– Fundamental studies
– Experimental studies
– Numerical studies
KW - Disposal
KW - Radioactive Waste
KW - Geology
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624955
DO - https://doi.org/10.1007/s12665-024-12075-2
SN - 1866-6299
VL - 84
IS - 3
SP - 1
EP - 6
PB - Springer Nature
AN - OPUS4-62495
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fürst, Richard
A1 - Häßler, Dustin
A1 - Stelzner, Ludwig
A1 - Hothan, Sascha
T1 - Fire resistance of existing steel structures with aged intumescent coating based on an in situ test method
N2 - Intumescent coatings are commonly used in civil engineering to increase the fire resistance of steel structures. Exposed to fire, the intumescent coating reacts and forms a thermal protective char around the steel member. Thus, the heating of the steel is significantly slowed down and the fire resistance can be improved. Information regarding the scope of application and the durability of intumescent coatings are given in national approvals or European Technical Assessment documents. Due to the environmental conditions, intumescent coatings are subjected to ageing effects, which can reduce the durability and their thermal protection performance. To predict the durability for several years, during the approval procedure the behaviour of intumescent coatings is predominantly extrapolated based on accelerated artificial ageing. The established German and European assessment procedures to test and assess durability assume a working life of at least 10 years. Additional evidence may be required for longer periods. However, at present there is no method of verifying the thermal performance of existing structural members on site. For this reason, BAM is conducting the research project "INSIST" [1] to develop a minimally invasive in situ test method to determine the fire resistance of existing steel structures with applied intumescent coating. The investigation includes the development of a mobile prototype furnace. The paper describes the test setup, the developed prototype furnace, and the results of the performed test programme on uncoated and coated steel specimens. Based on this, recommendations for the test procedure are given.
KW - In situ testing
KW - Fire resistance
KW - Intumescent coating
KW - Steel
KW - Thermal protection
KW - Durability
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629533
DO - https://doi.org/10.1016/j.firesaf.2025.104380
VL - 153
SP - 1
EP - 12
PB - Elsevier Ltd.
AN - OPUS4-62953
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ferrier, Emmanuel
A1 - Michel, Laurent
A1 - Thiele, Marc
A1 - Mercier, Julien
T1 - Strain-rate effect on the bond strength of external bonded reinforced carbon fiber-reinforced polymer for concrete structure
N2 - The aim of the presented study is to investigate the dynamic loading strength of an external bonded fiber-reinforced polymers (FRP) system under seismic loading. 16 bonded FRP samples under different loading speeds ranging as 0.0000167–0.8 m /s were examined to determine the characteristics of the FRP bond strength on the concrete. The mechanical tests involved measuring the concrete/FRP shear properties using a double-lap shear test. Sixteen concrete specimens were cast, strengthened and surface preparation, instrumented, and driven to failure in the LMC laboratory and the BAM laboratory (Germany). Dynamic loading increased the bonded strength mainly because of an increase in the concrete tensile strength. Experimental data are then analysed and competed with the equation given by the new European standard that develop the design of external bonded FRP. The characteristic properties and bonded strength obtained by design equation were compared. Based on the results design equation are modified.
KW - EBR strengthening system
KW - Desing bond strength
KW - Durability
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625354
DO - https://doi.org/10.1016/j.conbuildmat.2025.140216
SN - 1879-0526
VL - 466
SP - 1
EP - 14
PB - Elsevier Ltd.
AN - OPUS4-62535
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Strangfeld, Christoph
A1 - Müller-Vahl, H. F.
A1 - Nayeri, C. N.
A1 - Paschereit, C. O.
A1 - Greenblatt, D.
T1 - Airfoil synchronous surging and pitching
N2 - Combined surging and pitching of an airfoil at the identical frequency (i.e. synchronously), at four different phase differences, was investigated theoretically and experimentally. The most general unsteady theoretical formulation was adopted to calculate the lift coefficient, and then extended to explicitly compute the unsteady bound vortex sheet. This was used for comparison with experiments and facilitated the computation of both Joukowsky and impulsive-pressure lift contributions. Experiments were performed using a symmetric 18 % thick airfoil in an unsteady wind tunnel at an average Reynolds number of 3.0*10^5 , with a free-stream oscillation amplitude of 51 %, an angle-of-attack range of 2° +- 2° and a reduced frequency of 0.097. In general, excellent correspondence was observed between theory and experiment, representing the first direct experimental validation of the general theory. It was shown, both theoretically and experimentally, that the lift coefficient was not accurately represented by independent superposition of surging and pitching effects, due to variations in the instantaneous effective reduced frequency not accounted for during pure pitching. Deviations from theory, observed at angle-of-attack phase leads of 90° and 180°, were attributed to bursting of separation bubbles during the early stages of the acceleration phase. The largest deviations occurred when the impulsive-pressure lift contribution was small relative to the Joukowsky contribution, because the latter was most affected by bubble bursting. Bubble bursting resulted in large form-drag oscillations that occurred at identical phase angles within the oscillation cycle, irrespective of the phase difference between surging and pitching, as well as in the absence of pitching.
KW - Unsteady aerodynamics
KW - Dynamic stall
KW - Separation bubble
KW - Bubble bursting
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630068
DO - https://doi.org/10.1017/jfm.2025.220
SN - 1469-7645
VL - 1009
SP - 1
EP - 33
PB - Cambridge University Press (CUP)
AN - OPUS4-63006
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rosenbusch, Sjard Mathis
A1 - Diercks, Philipp
A1 - Kindrachuk, Vitaliy
A1 - Unger, Jörg F.
T1 - Integrating custom constitutive models into FEniCSx: A versatile approach and case studies
N2 - The development and integration of user-defined constitutive relationships into finite element (FE) tools using standardized interfaces play a pivotal role in advancing the capabilities of FE solvers for structural mechanics applications. While commercial FE solvers like Abaqus and Ansys have designed their interfaces to provide custom stresses, tangents, and updated history variables, the open-source solver FEniCSx remains efficient only when the constitutive update has an analytical representation. This restricts the application of FEniCSx for non-linear structural mechanics.
Since FEniCSx has become a powerful and popular open-source tool for solving partial differential equations, particularly due to its automatic computation of Hessians, we aim to develop a generalized interface to enhance its capability for constitutive modeling. This approach will address complex constitutive equations that require iterative solutions at the quadrature point level. Specific implementation challenges, such as using return-mapping procedures, can then be managed commonly. The provided interface for custom constitutive models offers a versatile way to implement them in various languages, including C++, Python, Rust, and Fortran. Finally, with UMATs for viscoplastic models as an example, we demonstrate how existing user subroutines can be incorporated into the interface and utilized within the FEniCSx framework.
KW - Finite element method
KW - Constitutive models
KW - FEniCSx
KW - UMAT
KW - Rust
KW - Python
KW - C++
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630439
DO - https://doi.org/10.1016/j.advengsoft.2025.103922
SN - 0965-9978
VL - 206
SP - 1
EP - 11
PB - Elsevier
CY - Amsterdam
AN - OPUS4-63043
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schwettmann-Lui, Kim
A1 - Nytus, Nina
A1 - Weigel, Sandra
A1 - Radenberg, Martin
A1 - Stephan, Dietmar
T1 - Effect of multiple-repeated aging and rejuvenation processes on bitumen properties evaluated with physical and chemical tests and multivariate analysis methods
N2 - This paper presents laboratory experiments on repeated bitumen aging and rejuvenation processes to assess multiple reuse feasibility. Three 50/70 penetration-graded bitumen samples were reused with four different rejuvenators without adding virgin binder. The experiments continued until significant material changes, such as inhomogeneities and increased stickiness, prevented reliable characterization. After each rejuvenation and aging process, physical and chemical properties were analyzed, resulting in a comprehensive dataset. Results indicate that the reuse of pure rejuvenators, without incorporating virgin binder, is limited. Cyclic reuse depends heavily on the rejuvenator and its interaction with the binder. Of the four rejuvenators tested, two bio-based products enabled the maximum reuse of four cycles. Therefore, the rejuvenators used in this project are more suitable as additives to improve the physical properties of the bitumen for reuse rather than as substitutes for the binder. The datasets were further evaluated using multivariate analysis methods to construct statistical models for two use cases: In the first use case, the samples are classified by their aging condition. In the second use case, the samples are differentiated according to the rejuvenators. The models were successfully validated, providing a promising framework for the classification of unknown bitumen samples for reuse.
KW - Bitumen
KW - Aging
KW - Rejuvenation
KW - Multiple recycling
KW - DSR measurements
KW - Reuse
KW - FTIR spectroscopy
KW - Multivariate analysis methods
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627563
DO - https://doi.org/10.1016/j.conbuildmat.2025.140734
SN - 1879-0526
VL - 472
SP - 1
EP - 16
PB - Elsevier Ltd.
AN - OPUS4-62756
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Capitain, C.
A1 - Schüßler, M.
A1 - Bugsel, B.
A1 - Zweigle, J.
A1 - Vogel, Christian
A1 - Leube, Peter
A1 - Zwiener, C.
T1 - Implementation of matrix-matched semiquantification of PFAS in AFFF-contaminated soil
N2 - This study presents a novel semiquantification approach for nontarget screening (NTS), combining matrix-matched calibration and ionization class-specific average calibration curves (ACCs) to address the lack of analytical reference standards for most per- and polyfluoroalkyl substances (PFAS). Ionization class-specific ACCs for carboxylic and sulfonic acids, sulfonamides, and cationic PFAS result in high accuracy, with median absolute accuracy quotients below 2.27×. The approach was applied to soil impacted by aqueous film-forming foam (AFFF) contamination. A total of 96 tentatively identified PFAS were semiquantified in addition to 28 quantified compounds based on available standards. Semiquantified concentrations exceeded those of target analytes, demonstrating the critical role of this method in capturing broader PFAS contamination. In this case, validation against extractable organofluorine (EOF) showed a 102% closed mass balance. The innovative approach not only enables comprehensive PFAS contamination assessment in complex matrices but also expands the scope of the NTS for environmental monitoring, remediation, and risk assessment of AFFF-contaminated sites.
KW - Per- and polyfluoroalkyl substances (PFAS)
KW - Contaminated soil
KW - Non-targeted analysis
KW - Combustion ion chromatography
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629445
DO - https://doi.org/10.1021/acs.est.4c14255
SN - 1520-5851
VL - 59
IS - 14
SP - 7338
EP - 7347
PB - American Chemical Society (ACS)
CY - Columbus, Ohio
AN - OPUS4-62944
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - McGonigle, Rebecca
A1 - Glasgow, Jodie
A1 - Houston, Catriona
A1 - Cameron, Iain
A1 - Homann, Christian
A1 - Black, Dominic J.
A1 - Pal, Robert
A1 - MacKenzie, Lewis E.
ED - MacKenzie, Lewis E.
T1 - Autoclave reactor synthesis of upconversion nanoparticles, unreported variables, and safety considerations
N2 - Autoclave reactors are widely used across chemical and biological sciences, including for the synthesis of upconversion nanoparticles (UCNPs) and other nanomaterials. Yet, the details of how autoclave reactors are used in such synthesis are rarely reported in the literature, leaving several key synthesis variables widely unreported and thereby hampering experimental reproducibility. In this perspective, we discuss the safety considerations of autoclave reactors and note that autoclaves should only be used if they are (a) purchased from reputable suppliers/manufacturers and (b) have been certified compliant with relevant safety standards. Ultimately, using unsuitable autoclave equipment can pose a severe physical hazard and may breach legal safety requirements. In addition, we highlight several parameters in autoclave synthesis that should be reported as standard to maximise the reproducibility of autoclave synthesis experiments across materials and chemistry research. We encourage users of autoclave synthesis vessels to: (1) adopt high-safety autoclaves and (2) report the many experimental variables involved to enhance experimental reproducibility.
KW - Reference material
KW - Nano
KW - Particle
KW - Shell
KW - Fluorescence
KW - Lifetime
KW - Decay kinetics
KW - Synthesis
KW - Quality assurance
KW - Method
KW - Energy transfer
KW - Upconversion
KW - Autoclave synthesis
KW - Data comparability
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625672
DO - https://doi.org/10.1038/s42004-025-01415-3
VL - 8
IS - 1
SP - 1
EP - 7
PB - Springer Science and Business Media LLC
AN - OPUS4-62567
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Poka, Konstantin
A1 - Ali, Sozol
A1 - Saeed, Waleed
A1 - Merz, Benjamin
A1 - Epperlein, Martin
A1 - Hilgenberg, Kai
T1 - Quality assurance via a cyber physical system of a PBF-LB/M machine
N2 - Powder Bed Fusion with Laser Beam of Metals (PBF-LB/M) faces challenges in reproducibility and quality assurance, even for widely applied alloys like AlSi10Mg. This work introduces a digital provenance framework for PBF-LB/M, showcased through the EOS M 300–4 multi-laser machine. An Extract, Transform, Load (ETL) pipeline autonomously captures machine data, including scan vectors as well as process signals, and organizes them into a Digital Shadow (DS). The DS is further extended by external data sources, such as Melt Pool Monitoring (MPM), to enable comprehensive analysis and root cause identification. This approach ensures continuous data representation and facilitates the development of new quality metrics. Moreover, the framework enhances quality assurance and traceability, supports compliance with industry standards, and improves productivity. It also enables more precise cost calculations and predictive maintenance. By addressing these challenges, the framework is essential for advancing PBF-LB/M in industrial applications, achieving greater consistency and scalability in production.
KW - PBF-LB/M
KW - Data driven quality assurance
KW - Data engineering
KW - Digital shadow
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625187
DO - https://doi.org/10.1007/s40964-025-00978-w
SN - 2363-9520
VL - 10
IS - 3
SP - 1771
EP - 1783
PB - Springer Science and Business Media LLC
AN - OPUS4-62518
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schackmann, Oliver
A1 - Márquez Reyes, Octavio A.
A1 - Memmolo, Vittorio
A1 - Lozano, Daniel
A1 - Prager, Jens
A1 - Moll, Jochen
A1 - Kraemer, Peter
T1 - Machine learning strategies with ensemble voting for ultrasonic damage detection in composite structures under varying temperature or load conditions
N2 - In recent years, the development of machine learning (ML) techniques has led to significant progress in the field of structural health monitoring with ultrasonic-guided waves. However, a number of challenges still need to be resolved for reliable operation in realistic settings. In this work, we consider the complex problem of experimental damage detection under varying temperature or load conditions where damage locations are not included in the training set. The ML techniques proposed here include supervised and unsupervised methods originally developed for image and time series classification combined with ensemble voting. A performance demonstration of the ML techniques is presented using benchmark datasets from the open-guided waves platform. The unsupervised approach is then applied to a new dataset from an experimental campaign carried out on a composite over-wrapped pressure vessel used for hydrogen storage with real defects. Results show that ensemble voting enables the effective combination of the predictions of multiple transducer pairs, even with a limited number of strong individual classifiers. When applied to unsupervised learning, this returns high accuracy also when real damage over the structure is considered.
KW - Structural-Health-Monitoring
KW - Ultrasonic guided waves
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631571
DO - https://doi.org/10.1177/14759217251333066
SN - 1741-3168
SP - 1
EP - 19
PB - Sage Publications
AN - OPUS4-63157
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hendricks, A.
A1 - Phillips, T. K.
A1 - Engl, T.
A1 - Plarre, Rudy
A1 - Martinson, V. G.
T1 - The bacterial microbiome in spider beetles and deathwatch beetles
N2 - The beetle family Ptinidae contains a number of economically important pests, such as the cigarette beetle Lasioderma serricorne, the drugstore beetle Stegobium paniceum, and the diverse spider beetles. Many of these species are stored product pests, which target a diverse range of food sources, from dried tobacco to books made with organic materials. Despite the threat that the 2,200 species of Ptinidae beetles pose, fewer than 50 have been surveyed for microbial symbionts, and only a handful have been screened using contemporary genomic methods. In this study, we screen 116 individual specimens that cover most subfamilies of Ptinidae, with outgroup beetles from closely related families Dermestidae, Endecatomidae, and Bostrichidae. We used 16S ribosomal RNA gene amplicon data to characterize the bacterial microbiomes of these specimens. The majority of these species had never been screened for microbes. We found that, unlike in their sister family, Bostrichidae, that has two mutualistic bacteria seen in most species, there are no consistent bacterial members of ptinid microbiomes. For specimens which had Wolbachia infections, we did additional screening using multilocus sequence typing and showed that our populations have different strains of Wolbachia than noted in previous publications.
KW - Sodalis
KW - Ptinidae
KW - Anobiidae
KW - Bostrichidae
KW - Dermestidae
KW - Bostrichoidea
KW - Wolbachia
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631564
DO - https://doi.org/10.1128/spectrum.01981-24
SN - 2165-0497
VL - 13
IS - 5
SP - 1
EP - 14
AN - OPUS4-63156
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Amano, Kofi Owusu Ansah
A1 - Tschirschwitz, Rico
A1 - Gimadieva, Elena
A1 - Köhler, Florian
A1 - Krause, Ulrich
T1 - Thermal runaway and explosibility of the gas release from 18650 sodium-ion cells of NFM chemistry
N2 - The present study investigates the thermal runaway behaviour and explosibility of the gas mixture released from sodium-ion batteries (SIBs). A total of 30 tests comprising two test series were performed using 18650 SIBs with a NaNi1/3Fe1/3Mn1/3O2 (NFM) chemistry. The cells of SOC level = 0 %, 25 %, 50 %, 75 % and 100 % were subjected to thermal abuse inside a 10 L pressurized reaction vessel. In test series 1, the tests were performed in an air atmosphere. In test series 2, an inert atmosphere was used. First, the total amount of gas released from the SIBs was calculated based on the temperature and pressure measured in the reaction vessel. Subsequently, a gas composition analysis was performed using a Fourier-transformed infrared (FTIR) spectrometer. This study revealed that the thermal runaway in SIBs could be categorized into four phases. At the onset of thermal runaway, the thermal runaway-induced explosion of the cells resulted in a rate of temperature rise ranging from 2 K/s to 70 K/s. The investigation further revealed a peak reaction temperature of 415 ◦C and a maximum pressure of 4 bar could be reached at thermal runaway in the 10 L vessel. The gas release of up to 5 ± 0.3 L (4 ± 0.2 L/Ah, 1.3 ± 0.1 L/Wh) from test series 1 and 2.4 ± 0.2 L (2 ± 0.1 L/Ah, 0.53 ± 0.04 L/Wh) from test series 2 showed a dependence on SOC and failure environment used. By applying Le Chatelier's mixing rule, the measured gas release from the air atmosphere showed a calculated lower explosion limit and upper explosion limit values of 4.8 % and 24 % in volume fraction, respectively.
KW - Sodium-ion battery
KW - Thermal runaway
KW - Gas release
KW - Gas explosion
KW - Explosion limit
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631782
DO - https://doi.org/10.1016/j.est.2025.116614
SN - 2352-152X
VL - 122
SP - 1
EP - 16
PB - Elsevier Ltd.
AN - OPUS4-63178
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Jafari, Abbas
A1 - Vlachas, K.
A1 - Chatzi, E.
A1 - Unger, Jörg F.
T1 - A Bayesian framework for constitutive model identification via use of full field measurements, with application to heterogeneous materials
N2 - In this paper, we present a Bayesian framework for the identification of the parameters of nonlinear constitutive material laws using full-field displacement measurements. The concept of force-based Finite Element Model Updating (FEMU-F) is employed, which relies on the availability of measurable quantities such as displacements and external forces. The proposed approach particularly unfolds the advantage of FEMU-F, as opposed to the conventional FEMU, by directly incorporating information from full-field measured displacements into the model. This feature is well-suited for heterogeneous materials with softening, where the localization zone depends on the random microstructure. Besides, to account for uncertainties in the measured displacements, we treat displacements as additional unknown variables to be identified, alongside the constitutive parameters. A variational Bayesian scheme is then employed to identify these unknowns via approximate posteriors under the assumption of multivariate normal distributions. An optimization problem is then formulated and solved iteratively, aiming to minimize the discrepancy between true and approximate posteriors. The benefit of the proposed approach lies in the stochastic nature of the formulation, which allows to tackle uncertainties related to model parameters and measurement noise. We verify the efficacy of our proposed framework on two simulated examples using gradient damage model with a path-dependent nonlinear constitutive law. Based on a nonlocal equivalent strain norm, this constitutive model can simulate a localized damage zone representing softening and cracking. The first example illustrates an application of the FEMU-F approach to cracked structures including sensitivity studies related to measurement noise and parameters of the prior distributions. In this example, the variational Bayesian solver demonstrates a sizable advantage in terms of computational efficiency compared to a traditional least-square optimizer. The second example demonstrates a sub-domain analysis to tackle challenges associated with limited domain knowledge such as uncertain boundary conditions.
KW - Constitutive model identification
KW - Full-field measurements
KW - Variational Bayes
KW - Force-based finite element model updating
KW - FEMU-F
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615476
DO - https://doi.org/10.1016/j.cma.2024.117489
SN - 1879-2138
VL - 433
IS - Part A
SP - 1
EP - 32
PB - Elsevier B.V.
AN - OPUS4-61547
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pfennig, A.
A1 - Simkin, Roman
T1 - Identifying the initial corrosion fatigue failure based on dropping electrochemical potential
N2 - The corrosion fatigue of duplex stainless-steel X2CrNiMoN22-5-3 can be determined by purely alternating axial cyclic load to failure using hour-glass shaped specimens. The experimental setup comprises a corrosion chamber allowing for the circulation of an aquifer electrolyte heated to 369 K simulating a carbon capture and storage as well as geothermal power plant environment. During engineering of a carbon storage site or geothermal power plant, it may be crucial to determine the failure onset of a component beforehand. Therefore, an algorithm with 93.3% reliability was established based on splitting the measured potential values into ten time series with a capacity of ten values. The failure of corrosion fatigue specimens in a geothermal environment correlates to the drop of the curves of the electrochemical potential which is measured simultaneously within the corrosion chamber. Crack initiation was, therefore, successfully derived from the electrochemical potential.
KW - Corrosion fatigue
KW - Surface corrosion
KW - CO2
KW - Crack initiation
KW - Geothermal energy production
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629310
DO - https://doi.org/10.3390/app15010403
SN - 2076-3417
VL - 15
IS - 1
SP - 1
EP - 15
PB - MDPI
CY - Basel
AN - OPUS4-62931
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kumar, Sumit
A1 - Swaminathan, Srinivasan
A1 - Hesse, Rene
A1 - Goldbeck, Hennig
A1 - Ding, Wenjin
A1 - Bonk, Alexander
A1 - Bauer, Thomas
T1 - Understanding the effect of oxide ions on Solar Salt chemistry and corrosion mechanism of 316L stainless steel at 600 °C
N2 - Solar Salt (60 wt% NaNO3, 40 wt% KNO3), used in Concentrated Solar Power (CSP) Thermal Energy Storage (TES) technology, can decompose into various products at elevated temperatures, with oxide ions being one of the known corrosive byproducts. The study mimics Solar Salt aging by intentionally adding sodium peroxide (Na2O2) and sodium oxide (Na2O) at concentrations of 0.005–0.33 wt% to investigate their role in the corrosion of austenitic stainless steel at 600 °C in typical operating conditions. Salt chemistry (nitrite, nitrate, oxide ions, and metal cations) was analyzed every 24 h, and steel corrosion after 168 h was assessed by weight change, corrosion rate, phase analysis, and cross-sectional morphology. Results reveal that at or above 0.135 wt% added Na2O2/Na2O leads to a quasi-steady-state equilibrium of oxide ions in the salt. Interestingly, at these concentrations, the presence of steel further decreases oxide ion concentration. Furthermore, above 0.135 wt%, the corrosion rate increases significantly, along with increased spallation, porosity and disintegration of the corrosion layer, forming a non-protective layer. This study highlights the critical role of oxide ions in the corrosion process.
KW - Solar Salt
KW - High temperature corrosion
KW - Thermal Energy Storage
KW - Alkali oxides
KW - Austenitic stainless steel
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628463
DO - https://doi.org/10.1016/j.corsci.2025.112849
SN - 1879-0496
VL - 249
SP - 1
EP - 17
PB - Elsevier Ltd.
AN - OPUS4-62846
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - John, Elisabeth
A1 - Jakob, Cordula
A1 - Pott, Ursula
A1 - Sando, Mona
T1 - Repeatability and reproducibility challenges of isothermal heat flow calorimetry with in situ mixing
N2 - Isothermal heat flow calorimetry evaluates heat development during binder reactions. It distinguishes between in situ calorimetry, where mixing occurs within the device, and ex situ calorimetry, involving externally mixed samples. Despite ex situ calorimetry being a standard method in binder research, in situ calorimetry is underutilized. This paper aims to promote its adoption by summarizing challenges related to repeatability and reproducibility and offering solutions. The initial section addresses repeatability issues caused by preventable errors, providing a structured guide for experimental design. It was found that water leakage had minimal impact, and sample size is crucial for data robustness. The second section examines operational challenges, revealing that frictional heating, affecting recorded heat, can be minimized with an optimized mixing protocol. The final part highlights that significant errors in measured data stem from signal delay and heat loss, offering methods to correct these issues for improved reproducibility in in situ calorimetric experiments.
KW - In situ calorimetry
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628431
DO - https://doi.org/10.1016/j.cemconres.2025.107872
SN - 1873-3948
VL - 194
SP - 1
EP - 11
PB - Elsevier Ltd.
AN - OPUS4-62843
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Baeßler, Matthias
A1 - Simon, Patrick
T1 - Ballasted track on vibrating bridge decks: physical mechanisms, empirical findings, and a proposal for assessment
N2 - This paper summarizes the key findings and physical mechanisms and provides information on open questions and the assessment of railway bridge superstructure vibrations. Bridges are classic disruption points on a railway track. If bridge superstructures are dynamically excited by train traffic, the vertical accelerations of the track must be considered. For a ballasted track, this can lead to the destabilization of the ballast track, as the bridge superstructure acts like a vibrating table. In this respect, the paper explains in more detail what is meant by destabilization, when this destabilization occurs and how various influencing parameters such as acceleration amplitude, the vibration sequence and frequency affect its occurrence. In the InBridge4EU project, gaps in knowledge such as the effect of single impulse loads are being investigated experimentally. A new test facility has been set up for this purpose, the initial results of which are presented here. An essential element in the assessment of this scenario is the stability of the track under high compression forces with simultaneous dynamic excitation of the superstructure. A new approach for the assessment of bridge vibrations with respect to lateral stability is presented.
KW - Railway bridge dynamics
KW - Bridge deck acceleration
KW - Ballast destabilization
KW - Lateral track stability
KW - Track buckling
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630972
DO - https://doi.org/10.1142/S0219455425400243
SN - 0219-4554
SN - 1793-6764
IS - 2540024
SP - 1
EP - 27
PB - World Scientific
CY - Singapore
AN - OPUS4-63097
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -