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Atomistic simulations are integral to the knowledge and design of glasses, but are nonetheless challenging due to slow structural dynamics, complex workflows, and issues of data management. With advances in high-throughput modeling and machine-learned interatomic potentials, it is worth increasing the Findability, Accessibility, Interoperability, and Reusability (FAIR) of these simulations. Here we present a Python package for the automated setup, execution, and analysis of atomistic simulations of glasses. The software package has semi-to-fully automated modules for the setup of molecular dynamics simulations, preparation of glassy systems, calculation of properties (elastic moduli, viscosity), and structural analysis of the resulting atomic configurations across short- and medium-range order. The computational and workflow management capability is based on the pyiron framework. Showcases of the automated glass preparation, property calculation, and analysis will be presented. The package includes a dedicated web application programming interface for use by large language models. We therefore provide an extensible platform for standardized, FAIR, AI-assisted atomistic simulation of glasses.
This is the first-ever report of igniting a combustive process that we tentatively denote as a mixing-induced self-propagating reaction (MXSR) in an inorganic system by a simple intensive mixing of the educts. The occurrence of MXSR is proven by observing a spike during in situ temperature monitoring. We demonstrate this on the example of agitating copper and sulfur powders in a ball-free planetary mill jar, igniting a MXSR without the external heating or the mechanical impact. Intensive powder agitation yields a mixture of nanocrystalline covellite (CuS) and digenite (Cu1.8S) in under 2 min. MXSR ignition thresholds are precisely determined (jar filling ≥40%, mixing speed ≥700 rpm, Cu:S molar ratio of 0.625–1.00). If these thresholds are not respected, a gradual reaction partly proceeds and an unstable mixture of digenite and non-reacted sulfur is formed, which is transformed into covellite with time. In specific cases, MXSR can be ignited within a few minutes after the termination of mixing. In the end, scalability to 40 and 62.5 g scales in planetary and mixer mills, respectively, is demonstrated and the products' thermoelectric utility for waste heat conversion is showcased. The proposed MXSR pathway overcomes state-of-the-art limitations in mechanochemistry, including product contamination from milling media abrasion and energy-intensive activation, while achieving decent alignment with green chemistry (100% atom economy, 88% and 91% reaction mass efficiency for the experiments performed on a larger scale in a mixer and planetary mill, respectively).
Accurate extraction of the complex dielectric constant in the terahertz (THz) band is essential for material characterization and non-destructive evaluation yet remains challenging due to the ill-posed nature of electromagnetic inverse problems and the limited availability of reliable reference data. In this work, a field-material couple neural network (FMCNN) is proposed to retrieve the complex dielectric constant directly from THz measurements. The FMCNN consists of a field neural network and a material neural network that are strongly coupled through the frequency-domain Maxwell equations in the form of a Helmholtz equation, with the governing physics enforced by partial differential equation and boundary condition constraints. This formulation enables zero-shot physics-informed learning inversion, requiring only measured test data as input. The extracted dielectric constants are validated by comparison with results from a one-dimensional normal-incidence model and the Drude–Lorentz model, showing good agreement over a broad frequency range, particularly above 0.2 THz. These results demonstrate that the FMCNN provides a physics-consistent and data-efficient approach for material parameter extraction in the THz band, offering an alternative to conventional model-based methods.
The capability to produce complexly and individually shaped metallic parts is one of the main advantages of the laser powder bed fusion (PBF-LB/M) process. However, the thermal history during additive manufacturing of complex components can differ significantly from the thermal history of geometrically primitive test specimens. This can result in divergent microstructures and resulting mechanical properties. It drastically limits the comparability of different built parts and requires expensive full component testing. Moreover, the thermal history as the spatiotemporal temperature distribution has been identified as a major cause for flaw formation. Therefore, it can be hypothesized that a similar thermal history between components and test specimens enhances their comparability. In this talk, the concept of representative test specimens is introduced, which enables the transfer of thermal histories from complex geometries to simple geometries, which can lead to better comparability of material properties.
Despite EU-driven standardization efforts, the lack of harmonized analytical workflows still limits the compa rability of microplastic (MP) measurements across laboratories. This study evaluates three infrared (IR)-based techniques (µ-FTIR, FPA-FTIR, and QCL-LDIR) using a metrologically characterized polyethylene terephthalate (PET) representative test material (RTM) containing 1318 ±73 particles per tablet (20–500 µm). Independent laboratories applied their routine analytical workflows, while µ-Raman spectroscopy served as the orthogonal reference method. The results identify 50 µm as a critical metrological threshold influencing IR analytical performance. Above 50 µm, IR-based methods showed closer agreement with Raman values and reduced dispersion compared to smaller fractions, with recoveries ranging from 28–54% for QCL-LDIR, 60–73% for FPA-FTIR, and 83–108% for µ-FTIR. Below 50 µm, recoveries decreased (µ-FTIR: 41–44%; FPA-FTIR: 36–54%; QCL-LDIR: 59–95%), although the broad interlaboratory range observed for QCL-LDIR indicates that optimized analytical workflows can sub stantially improve performance. Z-score and statistical analyses further showed that analytical performance was strongly size-dependent and influenced by both instrumental characteristics and laboratory-specific workflows. Supplementary experiments using a low-load PET RTM (96 ±14 particles per tablet, 20–500 µm) improved agreement with the Raman reference, confirming that particle crowding may contribute to analytical bias. Overall, the study shows that high internal precision may coexist with systematic bias, emphasizing that reproducibility alone is insufficient to ensure metrological reliability and interlaboratory comparability. These findings support size-resolved performance evaluation and the harmonization of analytical workflows to achieve robust and comparable microplastic measurements.
Grüner Wasserstoff wird in Zukunft einen entscheidenden Beitrag zu einer nachhaltigen Energieversorgung leisten. Für Deutschland ist der Aufbau eines „Wasserstoff-Kernnetzes” aus Ferngasleitungen mit einer Gesamtlänge von rund 9.700 Kilometern bis zum Jahr 2032 vorgesehen. Etwa 60 % dieser Leitungen werden aus umgestellten Erdgasleitungen bestehen, der Rest wird durch entsprechende Neubauten ergänzt. Wie im Erdgasnetz wird auch im Wasserstoff-Kernnetz das Schweißen an in Betrieb befindlichen, druckführenden Rohrleitungen erfolgen, beispielsweise bei Reparaturen oder Netzerweiterungen. Dabei ist für Wasserstoffleitungen eine erhöhte Wasserstoffaufnahme in die Rohrleitung durch die beim Schweißen auftretenden erhöhten Temperaturen an der Schweißstelle und insbesondere an der dem Druckwasserstoff exponierten Rohrinnenseite denkbar. Dies könnte die Integrität der Rohrleitung beeinflussen. Das übergeordnete Ziel des Projekts „H2-SuD“ war daher der generelle Nachweis der Übertragbarkeit der im Erdgasnetz etablierten Verfahren zum Schweißen an druckführenden Rohrleitungen unter Wasserstoff, ohne die Leitungsintegrität zu gefährden. Hierzu wurden über 30 für das Gasnetz repräsentative Kombinationen aus Wanddicke, Nennweite und Festigkeit für unterschiedlichste Schweißparameterbereiche für das E-Hand- und WIG-Schweißen untersucht und das sichere Schweißen an Demonstratoren nachgewiesen. Die erarbeiteten Ergebnisse (unter anderem für die Anpassung der Mindestwanddicke) sollen zeitnah in das geltende DVGW-Regelwerk (unter anderem Arbeitsblatt GW 350) überführt werden.
The integration of distributed fiber optic sensors (DFOSs) into prestressed concrete bridges represents a promising advancement in infrastructure monitoring. DFOSs provide continuous, high-resolution, and spatially resolved measurements of strain and temperature, making them particularly suitable for monitoring critical components in prestressed systems. They can be seamlessly integrated into new bridge constructions at relatively low additional cost, enabling structural monitoring to begin as early as the construction phase. Furthermore, DFOSs offer the unique ability to detect and localize damage that remains invisible to conventional visual inspection methods. These advantages position DFOSs as a valuable technology for enhancing the long-term safety, reliability, and digitalization of bridge infrastructure.
This research demonstrates the potential of static distributed fiber optic strain measurements conducted along DFOSs embedded in newly constructed prestressed concrete bridges. The applications include load testing and controlled damage induction of the prestressing strands.
The measurement results presented herein provide insights into the application specific sensitivity of Rayleigh based measurement methods, with consideration of the position and configuration of the embedded DFOSs.