TY - JOUR
A1 - Maulas, Kryzzyl M.
A1 - Paredes, Charla S.
A1 - Tabelin, Carlito Baltazar
A1 - Jose, Mark Anthony
A1 - Opiso, Einstine M.
A1 - Arima, Takahiko
A1 - Park, Ilhwan
A1 - Mufalo, Walubita
A1 - Ito, Mayumi
A1 - Igarashi, Toshifumi
A1 - Phengsaart, Theerayut
A1 - Villas, Edrhea
A1 - Dagondon, Sheila L.
A1 - Metillo, Ephrime B.
A1 - Uy, Mylene M.
A1 - Manua, Al James A.
A1 - Villacorte-Tabelin, Mylah
T1 - Isolation and Characterization of Indigenous Ureolytic Bacteria from Mindanao, Philippines: Prospects for Microbially Induced Carbonate Precipitation (MICP)
N2 - Microbially induced carbonate precipitation (MICP), a widespread phenomenon in nature, is gaining attention as a low-carbon alternative to ordinary Portland cement (OPC) in geotechnical engineering and the construction industry for sustainable development. In the Philippines, however, very few works have been conducted to isolate and identify indigenous, urease-producing (ureolytic) bacteria suitable for MICP. In this study, we isolated seven, ureolytic and potentially useful bacteria for MICP from marine sediments in Iligan City. DNA barcoding using 16s rDNA identified six of them as Pseudomonas stutzeri, Pseudomonas pseudoalcaligenes, Bacillus paralicheniformis, Bacillus altitudinis, Bacillus aryabhattai, and Stutzerimonas stutzeri but the seventh was not identified since it was a bacterial consortium. Bio-cementation assay experiments showed negligible precipitation in the control (without bacteria) at pH 7, 8, and 9. However, precipitates were formed in all seven bacterial isolates, especially between pH 7 and 8 (0.7–4 g). Among the six identified bacterial species, more extensive precipitation (2.3–4 g) and higher final pH were observed in S. stutzeri, and B. aryabhattai, which indicate better urease production and decomposition, higher CO2 generation, and more favorable CaCO3 formation. Characterization of the precipitates by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) and attenuated total reflectance Fourier transform spectroscopy (ATR-FTIR) confirmed the formation of three carbonate minerals: calcite, aragonite, and vaterite. Based on these results, all six identified indigenous, ureolytic bacterial species from Iligan City are suitable for MICP provided that the pH is controlled between 7 and 8. To the best of our knowledge, this is the first report of the urease-producing ability and potential for MICP of P. stutzeri, P. pseudoalcaligenes, S. stutzeri, and B. aryabhattai.
KW - Calcium carbonate
KW - Microbially induced carbonate precipitation (MICP)
KW - Ureolytic bacteria
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600888
DO - https://doi.org/10.3390/min14040339
VL - 14
IS - 4
SP - 1
EP - 15
PB - MDPI
AN - OPUS4-60088
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Casperson, Ralf
A1 - Friedrich, Alexander
A1 - Heckel, Thomas
A1 - Zhang, Tianyun
T1 - Verwendung von DICONDE bei der Eisenbahn-Schienenprüfung
N2 - Bei der zerstörungsfreien Prüfung verlegter Eisenbahnschienen werden die Rohdaten derzeit in proprietären Datenformaten gespeichert und auf Datenträgern zwischen den Prüfzügen und den auswertenden Stellen versendet. Die proprietären Datenformate sind in der Regel nur den Herstellern der Prüfsysteme bekannt und deren Dokumentation nicht allgemein zugänglich.
Die „Standard Practice for Digital Imaging and Communication in Nondestructive Evaluation“ (DICONDE), basierend auf dem medizinischen Standard „Digital Imaging and Communication in Medicine“ (DICOM), ermöglicht es, sowohl Prüfdaten als auch Prüfergebnisse und Streckeninformationen in einem standardisierten Format zu speichern und zwischen verschiedenen Endpunkten zu übertragen.
Das Poster gibt zunächst einen kurzen Überblick über die hierarchische Struktur von DICONDE und zeigt dann, wie DICONDE bei der Prüfung verlegter Eisenbahnschienen verwendet werden kann. Die geometrischen Besonderheiten (mehrere Kilometer Länge pro Prüffahrt, kurviger Streckenverlauf) stellen dabei eine besondere Herausforderung dar. Im Rahmen des mFUND-geförderten Projektes „Arteficial Intelligence for Railway Inspection (AIFRI)“, Förderkennzeichen 19FS2014C, wurde ein Vorschlag für eine Erweiterung des DICONDE-Standards für die Schienenprüfung erarbeitet und bei der ASTM eingereicht.
T2 - DGZfP Jahrestagung 2024
CY - Osnabrück, Germany
DA - 05.05.2024
KW - DICONDE
KW - Eisenbahn
KW - Schienenprüfung
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600204
DO - https://doi.org/10.58286/29500
SP - 1
EP - 5
PB - NDT.net
AN - OPUS4-60020
LA - deu
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 - Design and implementation of a machine log for PBF-LB/M on basis of IoT communication architectures and an ETL pipeline
N2 - AbstractPowder Bed Fusion with Laser Beam of Metals (PBF-LB/M) has gained more industrial relevance and already demonstrated applications at a small series scale. However, its widespread adoption in various use cases faces challenges due to the absence of interfaces to established Manufacturing Execution Systems (MES) that support customers in the predominantly data-driven quality assurance. Current state-of-the-art PBF-LB/M machines utilize communication architectures, such as OPC Unified Architecture (OPC UA), Message Queuing Telemetry Transport (MQTT) and Representational State Transfer Application Programming Interface (REST API). In the context of the Reference Architecture Model Industry 4.0 (RAMI 4.0) and the Internet of Things (IoT), the assets, particularly the physical PBF-LB/M machines, already have an integration layer implemented to communicate data such as process states or sensor values. Missing is an MES component acting as a communication and information layer. To address this gap, the proposed Extract Transform Load (ETL) pipeline aims to extract relevant data from the fabrication of each build cycle down to the level of scan vectors and additionally to register process signals. The suggested data schema for archiving each build cycle adheres to all terms defined by ISO/TC 261—Additive Manufacturing (AM). In relation to the measurement frequency, all data are reorganized into entities, such as the AM machine, build cycle, part, layer, and scan vector. These scan vectors are stored in a runtime-independent format, including all metadata, to be valid and traceable. The resulting machine log represents a comprehensive documentation of each build cycle, enabling data-driven quality assurance at process level.
KW - FAIR data
KW - Data-driven quality assurance
KW - Laser powder bed fusion
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601256
DO - https://doi.org/10.1007/s40964-024-00660-7
SN - 2363-9512
SP - 1
EP - 12
PB - Springer Science and Business Media LLC
AN - OPUS4-60125
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schlögl, Johanna
A1 - Goldammer, Ole
A1 - Bader, Julia
A1 - Emmerling, Franziska
A1 - Riedel, Sebastian
T1 - Introducing AFS ([Al(SO3F)3]x) – a thermally stable, readily available, and catalytically active solid Lewis superacid
N2 - This paper introduces the thermally stable, solid Lewis superacid aluminium tris(fluorosulfate) (AFS), that is easy-to-synthesize from commercially available starting materials. Its applicability, e.g. in catalytic C–F bond activations, is shown.
KW - Lewis Acid
KW - C-F activation
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601001
DO - https://doi.org/10.1039/D4SC01753F
SN - 2041-6520
SP - 1
EP - 7
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-60100
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schmidt, Stephan
A1 - Hoffmann, Holger
A1 - Garbe, Leif-Alexander
A1 - Harrer, Andrea
A1 - Steiner, Markus
A1 - Himly, Martin
A1 - Schneider, Rudolf
T1 - Re-assessment of monoclonal antibodies against diclofenac for their application in the analysis of environmental waters
N2 - The non-steroidal anti-inflammatory drug (NSAID) diclofenac (DCF) is an important environmental contaminant occurring in surface waters all over the world, because, after excretion, it is not adequately removed from wastewater in sewage treatment plants. To be able to monitor this pollutant, highly efficient analytical methods are needed, including immunoassays. In a medical research project, monoclonal antibodies against diclofenac and its metabolites had been produced. Based on this monoclonal anti-DCF antibody, a new indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed and applied for environmental samples. The introduction of a spacer between diclofenac and the carrier protein in the coating conjugate led to higher sensitivity. With a test midpoint of 3 mg L−1 and a measurement range of 1–30 mg L−1, the system is not sensitive enough for direct analysis of surface water. However, this assay is quite robust against matrix influences and can be used for wastewater. Without adjustment of the calibration, organic solvents up to 5%, natural organic matter (NOM) up to 10 mg L−1, humic acids up to 2.5 mg L−1, and salt concentrations up to 6 g L−1 NaCl and 75 mg L−1 CaCl2 are tolerated. The antibody is also stable in a pH range from 3 to 12. Cross-reactivity (CR) of 1% or less was determined for the metabolites 40-hydroxydiclofenac (40-OH-DCF), 5-hydroxydiclofenac (5-OH-DCF), DCF lactam, and other NSAIDs. Relevant cross-reactivity occurred only with an amide derivative of DCF, 6-aminohexanoic acid (DCF-Ahx), aceclofenac (ACF) and DCF methyl ester (DCF-Me) with 150%, 61% and 44%, respectively. These substances, however, have not been found in samples. Only DCF-acyl glucuronide with a cross-reactivity of 57% is of some relevance. For the first time, photodegradation products were tested for cross-reactivity. With the ELISA based on this antibody, water samples were analysed. In sewage treatment plant effluents, concentrations in the range of 1.9–5.2 mg L−1 were determined directly, with recoveries compared to HPLC-MS/MS averaging 136%.
Concentrations in lakes ranged from 3 to 4.4 ng L−1 and were, after pre-concentration, determined with an average recovery of 100%
KW - Antikörper
KW - Immunoassay
KW - Wasser
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-602280
DO - https://doi.org/10.1039/d3ay01333b
VL - 16
IS - 21
SP - 3349
EP - 3363
PB - Royal Society of Chemistry (RSC)
CY - London
AN - OPUS4-60228
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Galleani, Gustavo
A1 - Lodi, Thiago A.
A1 - Conner, Robin L.
A1 - Jacobsohn, Luiz G.
A1 - de Camargo, Andrea Simone Stucchi
T1 - Photoluminescence and X-ray induced scintillation in Gd3+-Tb3+ co-doped fluoride-phosphate glasses, and derived glass-ceramics containing NaGdF4 nanocrystals
N2 - The glass system (50NaPO3–20BaF2–10CaF2–20GdF3)-xTbCl3 with x = 0.3, 1, 3, 5, and 10 wt % was investigated. We successfully produced transparent glass ceramic (GC) scintillators with x = 1 through a melt-quenching process followed by thermal treatment. The luminescence and crystallization characteristics of these materials were thoroughly examined using various analytical methods. The nanocrystallization of Tb3+-doped Na5Gd9F32 within the doped fluoride-phosphate glasses resulted in enhanced photoluminescence (PL) and radioluminescence (RL) of the Tb3+ ions. The GC exhibited an internal PL quantum yield of 33 % and the integrated RL intensity across the UV-visible range was 36 % of that reported for the commercial BGO powder scintillator. This research showcases that Tb-doped fluoridephosphate GCs containing nanocrystalline Na5Gd9F32 have the potential to serve as efficient scintillators while having lower melting temperature compared to traditional silicate and germanate glasses.
KW - Glass scintillator
KW - Fluoride phosphate glasses
KW - Gd3+
KW - Tb3+
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603588
DO - https://doi.org/10.1016/j.omx.2023.100288
VL - 21
SP - 1
EP - 9
PB - Elsevier B.V.
AN - OPUS4-60358
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tatzel, Michael
A1 - Oelze, Marcus
A1 - Frick, Daniel A.
A1 - Di Rocco, Tommaso
A1 - Liesegang, Moritz
A1 - Stuff, Maria
A1 - Wiedenbeck, Michael
T1 - Silicon and oxygen isotope fractionation in a silicified carbonate rock
N2 - Silicon isotope fractionation during silicification is poorly understood and impedes our ability to decipher paleoenvironmental conditions from Si isotopes in ancient cherts. To investigate isotope fractionation during silica-for-carbonate replacement we analyzed the microscale Si and O isotope composition in different silica phases in a silicified zebra dolostone as well as their bulk δ18O and Δ’17O compositions. The subsequent replacement of carbonate layers is mimicked by decreasing δ18O and δ30Si. The textural relationship and magnitude of Si and O isotope fractionation is best explained by near-quantitative silica precipitation in an open system with finite Si. A Rayleigh model for silicification suggests positive Ɛ30/28Si during silicification, conforming with predictions for isotope distribution at chemical equilibrium from ab-initio models. Application of the modelled Ɛ30Si-T relationship yields silicification temperatures of approx. 50°C. To reconcile the δ18Ochert composition with these temperatures, the δ18O of the fluid must have been between -2.5 and -4 ‰, compositions for which the quartz phases fall close to the oxygen equilibrium fractionation line in three-isotope space. Diagenetic silica replacement appears to occur in O and Si isotopic equilibrium allowing reconstructions of temperatures of silicification from Si isotopes and derive the δ18O composition of the fluid – a highly desired value needed for accurate reconstructions of the temperature- and δ18O histories of the oceans.
KW - Silicon isotopes
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603430
DO - https://doi.org/10.1016/j.chemgeo.2024.122120
SN - 0009-2541
VL - 658
SP - 1
EP - 13
PB - Elsevier B.V.
AN - OPUS4-60343
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Wosniok, Aleksander
A1 - Königsbauer, Korbinian
A1 - Nöther, Nils
A1 - Färber, Jan
A1 - Schaller, M.-Barbara
A1 - Krebber, Katerina
T1 - Distributed polymer optical fiber sensors using digital I-OFDR for geotechnical infrastructure health monitoring
N2 - We present a distributed polymer optical fiber sensor system for deformation monitoring of geotechnical infrastructure. The sensor system is based on the digital incoherent optical frequency domain reflectometry (I-OFDR) for the detection of local strain events along a perfluorinated polymer optical fiber (PF-POF) used as a sensing fiber. For the best possible load transfer, the PF-POFs were integrated onto geosynthetics which pose a sensor carrier for the sensing fiber. By using elastic PF-POF instead of a standard glass fiber as a sensing fiber the strain range of geosynthetics-integrated fiber optic sensors could be extended up to 10 % in accordance with the end-user requirements.
T2 - 11th European Workshop on Structural Health Monitoring
CY - Potsdam, Germany
DA - 10.06.2024
KW - Digital I-OFDR
KW - Distributed polymer optical fiber sensor
KW - Ddistributed strain sensing
KW - Smart geosynthetics
KW - Structural health monitoring
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603096
SP - 1
EP - 7
PB - NDT.net
AN - OPUS4-60309
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Charmi, Amir
A1 - Heimann, Jan
A1 - Duffner, Eric
A1 - Hashemi, Seyedreza
A1 - Prager, Jens
T1 - Application of deep learning for structural health monitoring of a composite overwrapped pressure vessel undergoing cyclic loading
N2 - Structural health monitoring (SHM) using ultrasonic-guided waves (UGWs) enables continuous monitoring of components with complex geometries and provides extensive information about their structural integrity and their overall condition. Composite overwrapped pressure vessels (COPVs) used for storing hydrogen gases at very high pressures are an example of a critical infrastructure that could benefit significantly from SHM. This can be used to increase the periodic inspection intervals, ensure safe operating conditions by early detection of anomalies, and ultimately estimate the remaining lifetime of COPVs. Therefore, in the digital quality infrastructure initiative (QI-Digital) in Germany, an SHM system is being developed for COPVs used in a hydrogen refueling station. In this study, the results of a lifetime fatigue test on a Type IV COPV subjected to many thousands of load cycles under different temperatures and pressures are presented to demonstrate the strengths and challenges associated with such an SHM system. During the cyclic testing up to the final material failure of the COPV, a sensor network of fifteen surface-mounted piezoelectric (PZT) wafers was used to collect the UGW data. However, the pressure variations, the aging process of the COPV, the environmental parameters, and possible damages simultaneously have an impact on the recorded signals. This issue and the lack of labeled data make signal processing and analysis even more demanding. Thus, in this study, semi-supervised, and unsupervised deep learning approaches are utilized to separate the influence of different variables on the UGW data with the final aim of detecting and localizing the damage before critical failure.
T2 - 11th European Workshop on Structural Health Monitoring
CY - Potsdam, Germany
DA - 10.06.2024
KW - Structural health monitoring
KW - Deep learning
KW - Ultrasonic-guided waves
KW - Anomaly detection
KW - Damage localization
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607396
DO - https://doi.org/10.58286/29751
SP - 1
EP - 8
AN - OPUS4-60739
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hupp, Vitus
A1 - Schartel, Bernhard
A1 - Flothmeier, K.
A1 - Hartwig, A.
T1 - Pyrolysis and flammability of phosphorus based flame retardant pressure sensitive adhesives and adhesive tapes
N2 - Pressure-sensitive adhesive tapes are used in a variety of applications such as construction, aircrafts, railway vehicles, and ships, where flame retardancy is essential. Especially in these applications, phosphorus-based flame retardants are often chosen over halogenated ones due to their advantages in terms of toxicity. Although there are pressure-sensitive adhesives with phosphorus flame retardants available on the market, their flame-retardant modes of action and mechanisms are not entirely understood. This research article provides fundamental pyrolysis research of three phosphorus-based flame retardants that exhibit different mechanisms in a pressuresensitive adhesive matrix. The flame-retardants modes of action and mechanisms of a 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) derivate, an aryl phosphate, and a self-synthesized, covalently bonded DOPO derivate (copolymerized) are investigated. The blended DOPO derivate is volatilized at rather low temperatures while the covalently bonded DOPO derivate decomposes together with the polymer matrix at the same temperature. Both DOPO derivates release PO radicals which are known for their flame inhibition. The aryl phosphate decomposes at higher temperatures, releases small amounts of aryl phosphates into the gas phase, and acts predominantly the condensed phase. The aryl phosphate acts as precursor for phosphoric acid and improves the charring of the pressure sensitive adhesive matrix. All flame retardants enhance the flammability of the adhesives depending on their individual mode of action while the covalently bonded flame retardant additionally improves the mechanical properties at elevated temperatures making it a promising future technology for pressure-sensitive adhesives.
KW - Pyrolysis of flame retardant
KW - Pyrolysis gas chromatography
KW - Mass spectrometry
KW - Phosphorus flame retardant
KW - Decomposition mechanism
KW - Flame retardant pressure sensitive adhesives
KW - Flame retardancy
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607192
DO - https://doi.org/10.1016/j.jaap.2024.106658
SN - 0165-2370
SN - 1873-250X
VL - 181
SP - 1
EP - 31
PB - Elsevier B.V.
AN - OPUS4-60719
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Johann, Sergej
A1 - Stürenberg, Jan
A1 - Tandon, Aditya
T1 - Robotergestütztes Bauwerksmonitoring basierend auf eingebetteter Sensorik
N2 - In den letzten Jahrzehnten hat sich das Bauwerksmonitoring (engl. „Structural Health Monitoring“, SHM) zu einer nützlichen Ergänzung routinemäßiger Inspektionen entwickelt. SHM ermöglicht die frühzeitige Erkennung von Schäden an Bauwerken und dadurch die frühe, und somit kostengünstige, Durchführung von Reparatur- und Wartungsarbeiten. Mit dem Aufkommen drahtloser Technologien und Fortschritten in der Informations- und Kommunikationstechnologie werden Bauwerke zunehmend mit drahtlosen Sensorknoten ausgestattet, um für SHM relevante Bauwerksdaten zu erfassen, zu analysieren und zu übertragen. Eine vielversprechende Methode für SHM ist die direkte Einbettung von Sensoren in den Beton. In diesem Beitrag wird ein Sensorsystem zur Einbettung in Beton vorgestellt, das in der Lage ist, die im Beton aufgenommenen Bauwerksdaten auszuwerten. Die Sensoren werden bei Bedarf von vierbeinigen Robotern mittels Radio Frequency Identification (RFID) ausgelesen und mit Energie versorgt, was einen automatisierten und effizienten Prozess ermöglicht. Der prototypische Prozess zur automatischen Erfassung von Bauwerksdaten mit eingebetteter Sensorik und vierbeinigen Robotern wird durch Tests in einer Büroumgebung validiert. Die Ergebnisse der Tests bestätigen die automatische und effiziente Erfassung von Bauwerksdaten, die eine frühzeitige Erkennung von Bauwerksschäden, auch von nicht sichtbaren Schäden, ermöglicht, und eine folgerichtige Weiterentwicklung des
modernen Bauwerksmonitorings repräsentiert.
T2 - 35. Forum Bauinformatik
CY - Hamburg, Germany
DA - 18.09.2024
KW - Radio Frequency Identification (RFID)
KW - Bauwerksmonitoring (SHM)
KW - Eingebettete Sensorik
KW - Vierbeinige Roboter
KW - Autonome Navigation
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621890
DO - https://doi.org/10.15480/882.13502
SP - 139
EP - 146
AN - OPUS4-62189
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tukhmetova, Dariya
A1 - Langhammer, Nicole
A1 - Vogl, Jochen
A1 - Meermann, Björn
T1 - Online Isotope Analysis of Sulfur in Proteins via Capillary Electrophoresis Coupled With Multicollector ICP‐MS (CE/MC‐ICP‐MS): A Proof of Concept Study
N2 - Isotope ratio analysis of sulfur in biological samples using inductively coupled plasma-mass spectrometry (ICP-MS) has gained significant interest for applications in quantitative proteomics. Advancements like coupling separation techniques with multicollector ICP-MS (MC-ICP-MS) enhance the throughput of species-specific sulfur isotope ratio measurements, fostering new avenues for studying sulfur metabolism in complex biological matrices. This proof-of-concept study investigates the feasibility of online CE/MC-ICP-MS for directly analyzing sulfur isotope ratios in proteins (albumin). Leveraging our previous work on the applicability of CE/ICP-MS for quantifying sulfur-containing biological molecules, we explore its potential for sulfur isotope analysis. Our results demonstrate that direct analysis of sulfur isotopes in albumin protein using online capillary electrophoresis MC-ICP-MS (CE/MC-ICP-MS) eliminates the need for laborious pretreatment steps, while yielding isotope ratios comparable to the reference values. Although initial precision can be improved through further system optimization and protein injection techniques, this approach paves the way for future analysis of mixtures of various biological compounds in, for example, clinical diagnosis studies.
KW - Isotope analysis
KW - Sulfur
KW - CE/MC-ICP-MS
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612439
DO - https://doi.org/10.1002/elps.202400128
SN - 0173-0835
SP - 1
EP - 6
PB - Wiley-Blackwell
CY - Weinheim
AN - OPUS4-61243
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bayerlein, Bernd
A1 - Schilling, Markus
A1 - Curran, Maurice
A1 - Campbell, Carelyn E.
A1 - Dima, Alden A.
A1 - Birkholz, Henk
A1 - Lau, June W.
T1 - Natural Language Processing-Driven Microscopy Ontology Development
N2 - AbstractThis manuscript describes the accelerated development of an ontology for microscopy in materials science and engineering, leveraging natural language processing (NLP) techniques. Drawing from a comprehensive corpus comprising over 14 k contributions to the Microscopy and Microanalysis conference series, we employed two neural network-based algorithms for NLP. The goal was to semiautomatically create the Microscopy Ontology (MO) that encapsulates and interconnects the terminology most frequently used by the community. The MO, characterized by its interlinked entities and relationships, is designed to enhance the quality of user query results within NexusLIMS. This enhancement is facilitated through the concurrent querying of related terms and the seamless integration of logical connections.
KW - Microscopy Ontology
KW - Knowledge Representation
KW - Semantic Interoperability
KW - Natural Language Processing
KW - Ontology Development
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-616942
DO - https://doi.org/10.1007/s40192-024-00378-y
SP - 1
EP - 12
PB - Springer Science and Business Media LLC
AN - OPUS4-61694
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Li, Yue
A1 - Colnaghi, Timoteo
A1 - Gong, Yilun
A1 - Zhang, Huaide
A1 - Yu, Yuan
A1 - Wei, Ye
A1 - Gan, Bin
A1 - Song, Min
A1 - Marek, Andreas
A1 - Rampp, Markus
A1 - Zhang, Siyuan
A1 - Pei, Zongrui
A1 - Wuttig, Matthias
A1 - Ghosh, Sheuly
A1 - Körmann, Fritz
A1 - Neugebauer, Jörg
A1 - Wang, Zhangwei
A1 - Gault, Baptiste
T1 - Machine learning‐enabled tomographic imaging of chemical short‐range atomic ordering
N2 - In solids, chemical short‐range order (CSRO) refers to the self‐organization of atoms of certain species occupying specific crystal sites. CSRO is increasingly being envisaged as a lever to tailor the mechanical and functional properties of materials. Yet quantitative relationships between properties and the morphology, number density, and atomic configurations of CSRO domains remain elusive. Herein, it is showcased how machine learning‐enhanced atom probe tomography (APT) can mine the near‐atomically resolved APT data and jointly exploit the technique's high elemental sensitivity to provide a 3D quantitative analysis of CSRO in a CoCrNi medium‐entropy alloy. Multiple CSRO configurations are revealed, with their formation supported by state‐of‐the‐art Monte‐Carlo simulations. Quantitative analysis of these CSROs allows establishing relationships between processing parameters and physical properties. The unambiguous characterization of CSRO will help refine strategies for designing advanced materials by manipulating atomic‐scale architectures.
KW - Chemical short-range order (CSRO)
KW - Atom probe tomography (APT)
KW - Machine learning
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623777
DO - https://doi.org/10.1002/adma.202407564
SN - 1521-4095
VL - 36
IS - 44
SP - 1
EP - 9
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-62377
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pfennig, Anja
A1 - Mohring, Wencke
A1 - Wolf, Marcus
T1 - The insignificant improvement of corrosion and corrosion fatigue behavior in geothermal environment applying Boehmit coatings on high alloyed steels
N2 - The efficacy of alumina-sol based coatings in a water-free atmosphere at high temperatures suggests a potential solution for enhancing the corrosion resistance of high-alloyed steels in Carbon Capture and Storage (CCS) environments. In this study, coupons of X20Cr13, designed for use as injection pipes with 13% Chromium and 0.20% Carbon (1.4021, AISI 420), were sol-gel coated with water and ethanol-based alumina. These coated coupons were then exposed to CO2-saturated saline aquifer water, simulating conditions in the Northern German Basin, for 1000 h at ambient pressure and 60 °C. Corrosion fatigue experiments were also conducted using specimens of X5CrNiMoCuNb16-4 (1.4542, AISI 630), a suitable candidate for geothermal applications, to assess the impact of the ethanol-based coating on the number of cycles to failure at different stress amplitudes. Unfortunately, the coating exhibited early spallation, resulting in corrosion kinetics and corrosion fatigue data identical to those of uncoated specimens. Consequently, the initially promising Boehmit coating is deemed unsuitable for CCS applications and further research therefore not advisable.
KW - Alumina coating
KW - High alloyed steel
KW - Pitting
KW - Surface corrosion
KW - CO2
KW - Pipeline
KW - Corrosion
KW - CCS
KW - CO2-storage
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623786
DO - https://doi.org/10.3390/app14041575
SN - 2076-3417
VL - 14
IS - 4
SP - 1
EP - 12
PB - MDPI
CY - Basel
AN - OPUS4-62378
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Vlach, Tomáš
A1 - Řepka, Jakub
A1 - Hájek, Jakub
A1 - Pošta, Jan
A1 - Fürst, Richard
A1 - Hájek, Petr
T1 - Shear Capacity of Hollow High-Performance Concrete Beams with Cross-Wound Carbon Fiber-Reinforced Polymer Reinforcement
N2 - This paper introduces cross-wound CFRP shear reinforcement of hollow HPC beams. The CFRP reinforcement was manufactured in the form of a square tubular mesh from carbon rovings oriented at ±45° from the longitudinal axis. The shear reinforcement was made in two variants from carbon yarns with linear densities of 1600 and 3700 tex. Tensile reinforcement made of BFRP bars was positioned directly around the hollow core and was used as a platform for manual winding of the shear reinforcement. The hollow beams were subjected to a three-point bending test with four configurations of the tensile BFRP reinforcement for better evaluation of the effect of the shear reinforcement under different conditions. The 1600 tex shear reinforcement increased the ultimate flexural strength by at least 89% compared to specimens without any shear reinforcement. The 3700 tex shear reinforcement yielded slightly better results in most cases but was not utilized to its full shear capacity as these specimens always failed in shear due to the delamination of the concrete matrix from the shear reinforcement. There was too much reinforcement in the beam cross-section.
KW - Hollow concrete beam
KW - Shear reinforcement
KW - Composite reinforcement
KW - Woven reinforcement
KW - Cross-wound reinforcement
KW - Fiber-reinforced polymer
KW - High-performance concrete
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623868
DO - https://doi.org/10.3390/polym17010075
SN - 2073-4360
VL - 17
IS - 1
SP - 1
EP - 13
PB - MDPI
AN - OPUS4-62386
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Paul, Nathalie
A1 - Karamitsou, Venetia
A1 - Giegerich, Clemens
A1 - Sadeghi, Afshin
A1 - Lücke, Moritz
A1 - Wagenhuber, Britta
A1 - Kister, Alexander
A1 - Rehberg, Markus
T1 - Building virtual patients using simulation-based inference
N2 - In the context of in silico clinical trials, mechanistic computer models for pathophysiology and pharmacology (here Quantitative Systems Pharmacology models, QSP) can greatly support the decision making for drug candidates and elucidate the (potential) response of patients to existing and novel treatments. These models are built on disease mechanisms and then parametrized using (clinical study) data. Clinical variability among patients is represented by alternative model parameterizations, called virtual patients. Despite the complexity of disease modeling itself, using individual patient data to build these virtual patients is particularly challenging given the high-dimensional, potentially sparse and noisy clinical trial data. In this work, we investigate the applicability of simulation-based inference (SBI), an advanced probabilistic machine learning approach, for virtual patient generation from individual patient data and we develop and evaluate the concept of nearest patient fits (SBI NPF), which further enhances the fitting performance. At the example of rheumatoid arthritis where prediction of treatment response is notoriously difficult, our experiments demonstrate that the SBI approaches can capture large inter-patient variability in clinical data and can compete with standard fitting methods in the field. Moreover, since SBI learns a probability distribution over the virtual patient parametrization, it naturally provides the probability for alternative parametrizations. The learned distributions allow us to generate highly probable alternative virtual patient populations for rheumatoid arthritis, which could potentially enhance the assessment of drug candidates if used for in silico trials.
KW - Simulation-based inference
KW - Machine learning
KW - Artificial intelligence
KW - Virtual patients
KW - Pathophysiology
KW - Pharmacology
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626050
DO - https://doi.org/10.3389/fsysb.2024.1444912
SN - 2674-0702
VL - 4
SP - 1
EP - 11
PB - Frontiers Media SA
AN - OPUS4-62605
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Weiss, Daniel
A1 - Asna Ashari, Parsa
A1 - Blind, Knut
T1 - Exploring the fuel-cell technological innovation system: Technology interactions in the mobility sector
N2 - With the rise of alternative sustainable powertrain technologies, the mobility paradigm has undergone fundamental changes in recent years. In the wake of the ongoing transition of the road-vehicle sector, fuel-cell vehicles (FCVs) have received increased political attention. However, they constitute only a tiny fraction of total road vehicles nowadays and still face competition from other powertrain technologies. Therefore, this study specifically focuses on how the focal technological innovation system of FCVs is influenced by the emerging electric vehicles (EVs) and established internal combustion engine vehicles (ICEVs) as its context structures. To this end, our time-series vector error correction models analyze the short- and long-run causalities between our focal TIS and its context structures. Using publications, patents, and standards as quantitative TIS indicators, we analyze the modes of technology interaction between FCVs and EVs and FCVs and ICEVs to determine the life-cycle phase of our focal FCV-TIS in more depth. Our results demonstrate that the FCV-TIS is in its formative phase based on the dominance of the EV and ICEV context structures. As policy implications, we derive application-sensitive technology policies that combine the benefits of each mobility technology toward the sustainable transition of the mobility sector.
KW - Technological innovation system (TIS)
KW - Technology interaction
KW - TIS-context relations
KW - Fuel-cell vehicles
KW - Electric vehicles
KW - Internal combustion engine vehicles
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626599
DO - https://doi.org/10.1016/j.trip.2024.101107
SN - 2590-1982
VL - 25
SP - 1
EP - 15
PB - Elsevier
CY - Amsterdam
AN - OPUS4-62659
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ladu, Luana
A1 - Morone, P.
T1 - Sustainability assessments of bio-based products: From research to practice (and standards)☆
N2 - The transition from a linear, fossil-based economy to a circular, bio-based economy is needed in order to achieve climate neutrality by 2050. However, it is important to ensure that the bio-based economy delivers the expected environmental and social impacts, by respecting and implementing sustainability principles. One effective way to reduce uncertainty regarding bio-based product properties and benefits is through the use of sustainability standards, certification schemes, and ecolabels. These measures can play a significant role in advancing the transition to a sustainable, circular bio-based economy. They provide a solid foundation for assessing sustainability of “green” products and initiatives and contribute greatly to building trust in products among consumers, providing a reliable framework for sevaluation. To measure the sustainability of bio-based products, several robust and reliable tools are under development, gathering evidence from research and collaborative efforts of several European projects.
KW - Bioeconomy
KW - Sustainability Assessment
KW - Standards
KW - Certifications
KW - Ecolabels
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623576
DO - https://doi.org/10.1016/j.socimp.2024.100041
VL - 3
SP - 1
EP - 4
PB - Elsevier Ltd.
AN - OPUS4-62357
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Völker, Tobias
A1 - Mensing, Friedrich
A1 - Kruschwitz, Sabine
T1 - Estimation of cement content in concrete by spatially resolved laser induced breakdown spectroscopy
N2 - The cement content in concrete significantly influences critical properties such as durability, permeability, strength, and workability. Traditional methods for estimating the cement content face limitations. These include the need for comprehensive chemical and solubility knowledge, extensive sample preparation, and their time-consuming and destructive nature. This study investigates the application of laser-induced breakdown spectroscopy (LIBS) as an alternative method. It involves probing concrete samples with high spatial resolution and analyzing the resultant spectra. The methodology is first tested on mesoscale concrete models to assess limitations and inherent errors. Subsequently, the methodology is applied to actual concrete samples with varying cement content and aggregate size distributions. The results demonstrate a promising accuracy, with an average relative error of approximately 8%. This paper offers a comprehensive evaluation of the method's advantages, limitations, and factors influencing its practical applicability in field conditions.
KW - LIBS
KW - Spectroscopy
KW - Cement content
KW - Elemental mapping
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-620112
DO - https://doi.org/10.1016/j.cemconres.2024.107714
SN - 1873-3948
VL - 189
SP - 1
EP - 10
PB - Elsevier Ltd.
AN - OPUS4-62011
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Alem, Sayed Ali Ahmad
A1 - Sabzvand, Mohammad Hossein
A1 - Govahi, Parnian
A1 - Poormehrabi, Pooria
A1 - Azar, Mahdi Hasanzadeh
A1 - Siouki, Sara Salehi
A1 - Rashidi, Reza
A1 - Angizi, Shayan
A1 - Bagherifard, Sara
T1 - Advancing the next generation of high-performance metal matrix composites through metal particle reinforcement
N2 - Metal matrix composites (MMCs) offer asignificant boost to achieve a wide range of advanced mechanical properties and improved performance for a variety of demanding applications. The addition of metal particles as reinforcement in MMCs is an exciting alternative to conventional ceramic reinforcements, which suffer from numerous shortcomings. Over the last two decades, various categories of metal particles, i.e., intermetallics, bulk metallic glasses, high-entropy alloys, and shape memory alloys, have become popular as reinforcement choices for MMCs. These groups of metal particles offer a combination of outstanding physico-mechanical properties leading to unprecedented performances; moreover, they are significantly more compatible with the metal matrices compared to traditional ceramic reinforcements. In this review paper, the recent developments in MMCs are investigated. The importance of understanding the active mechanisms at the interface of the matrix and the reinforcement is highlighted. Moreover, the processing techniques required to manufacture high-performance MMCs are explored identifying the potential structural and functional applications. Finally, the potential advantages and current challenges associated with the use of each reinforcement category and the future developments are critically discussed. Based on the reported results, the use of metal particles as reinforcement in MMCs offers a promising avenue for the development of advanced materials with novel mechanical properties. Further progress requires more in-depth fundamental research to realize the active reinforcing mechanisms at the atomic level to precisely identify, understand, and tailor the properties of the integrated composite materials.
KW - Intermetallic
KW - Composite
KW - Metal matrix composite
KW - Interface
KW - High entropy alloy
KW - Bulk metallic glass
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-620730
DO - https://doi.org/10.1007/s42114-024-01057-4
SN - 2522-0128
VL - 8
IS - 1
SP - 1
EP - 68
PB - Springer Nature
AN - OPUS4-62073
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Christensen, J. B.
A1 - Jørgensen, A. A.
A1 - Vandborg, M. H.
A1 - Thomas, P. J.
A1 - Lu, Xin
A1 - Failleau, G.
A1 - Eisermann, R.
A1 - Grüner-Nielsen, L.
A1 - Balslev-Harder, D.
A1 - Lassen, M.
A1 - Krenek, S.
T1 - Fiber-artefact methodology and calibration framework for Brillouin-based fiber sensing
N2 - We propose, and demonstrate, the use of a fiber-optical measurement artefact as a metrological tool for traceable distance calibration of distributed optical fiber sensors. The constructed fiber artefact consists of a lead-in fiber coupled to a fiber loop using a 3-dB coupler and is used to calibrate both a home-build Brillouin-OTDR setup and a custom version of a commercial Brillouin-OTDR interrogator build for distributed temperature sensing. For both interrogators, we demonstrate distance calibrations with 1-meter uncertainty (k=1) in the offset length and 0.1 % (1 m/km) uncertainty (k = 1) in the distance scale factor. In addition, it is shown that the fiber artefact can be used to assess undesired distance-dependent measurement biases.
KW - Distributed temperature sensing
KW - Metrology
KW - Distributed optical fiber sensing
KW - Brillouin optical time-domain reflectrometry
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618853
DO - https://doi.org/10.1364/OE.544659
SN - 1094-4087
VL - 32
IS - 26
SP - 45483
EP - 45493
PB - Optica Publishing Group
AN - OPUS4-61885
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Shafiey, Hassan
A1 - Gogol-Döring, Andreas
A1 - McMahon, Dino Peter
A1 - Doublet, Vincent
A1 - Disayathanoowat, Terd
A1 - Paxton, Robert J.
T1 - A new variant of slow bee paralysis virus revealed by transcriptome analysis
N2 - Using NGS data from an RNA-seq library, we reveal a novel variant of slow bee paralysis virus (SBPV) in a pooled sample of adult honey bees (Apis mellifera) collected in southwest Germany. We provide its sequence (NCBI Accession No. PP100271) and demonstrate that it is infective for adult honey bees by feeding.
KW - SBPV
KW - Apis mellifera
KW - +ss RNA virus
KW - Iflaviridae
KW - Transmission
KW - NGS
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-620900
DO - https://doi.org/10.1080/00218839.2024.2425912
SP - 1
EP - 5
PB - Taylor & Francis
AN - OPUS4-62090
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schneider, Mike
A1 - Couzinié, Jean-Philippe
A1 - Shalabi, Amin
A1 - Ibrahimkhel, Farhad
A1 - Ferrari, Alberto
A1 - Körmann, Fritz
A1 - Laplanche, Guillaume
T1 - Effect of stacking fault energy on the thickness and density of annealing twins in recrystallized FCC medium and high-entropy alloys
N2 - This work aims to predict the microstructure of recrystallized medium and high-entropy alloys (MEAs and HEAs) with a face-centered cubic structure, in particular the density of annealing twins and their thickness. Eight MEAs and five HEAs from the Cr-Mn-Fe-Co-Ni system are considered, which have been cast, homogenized, cold-worked and recrystallized to obtain different grain sizes. This work thus provides a database that could be used for data mining to take twin boundary engineering for alloy development to the next level. Since the stacking fault energy is known to strongly affect recrystallized microstructures, the latter was determined at 293 K using the weak beam dark-field technique and compared with ab initio simulations, which additionally allowed to calculate its temperature dependence. Finally, we show that all these data can be rationalized based on theories and empirical relationships that were proposed for pure metals and binary Cu-based alloys.
KW - CoCrFeMnNi HEAs and MEAs
KW - Recrystallization
KW - Transmission electron microscopy (TEM)
KW - Electron backscatter diffraction
KW - Grain boundary engineering
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-629346
DO - https://doi.org/10.1016/j.scriptamat.2023.115844
SN - 1359-6462
VL - 240
SP - 1
EP - 6
PB - Elsevier
CY - Amsterdam
AN - OPUS4-62934
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Sridaran Venkat, Ramanan
A1 - Stamm, Michael
A1 - Wittmann, Jost
A1 - Lauterbach, Helge
A1 - Bleier, Michael
T1 - Harnessing the power of thermal imagery and visual inspection- a mean for reliable damage detection of wind turbine rotor blades
N2 - Generation of green electricity as part of the energy transition is leading to a growing market in the wind energy sector all over the world. Maintenance and inspection are key-factor for the reliable, safe and efficient operation of wind turbines. Regular maintenance of rotor blades focuses on damage such as erosion on the leading edge of the profile, delamination and thermal cracks due to lightning strikes. To date, visual inspection by technicians (climbers) has been the state of the art. Recently, drone-based inspections using visual cameras have become more common, enabling fast, reliable and cost-effective inspections. However, no internal damage to the rotor blades are detectable during such an inspection. This deficiency is often compensated by thermography, a recognized method for detecting damages beneath the surface of an object. Thermography has been promoted and continuously developed at BAM for years. In the first part of this paper, the authors present the concept for a drone-based multisensory system that combines a thermal camera, a high-resolution visual camera and a 3D Laser scanner.The system provides a comprehensive view of the rotor blade samples internal and external conditions. In the second part of the paper, we present a lab-based demonstrator comprising an infrared camera and an RGB camera. We elaborate on the process for fusing the images comprising the calibration, image preprocessing and image registration.
T2 - 11th European Workshop on Structural Health Monitoring
CY - Potsdam, Germany
DA - 10.06.2024
KW - Wind rotor blade inspection
KW - Thermography
KW - Data fusion
KW - Drone inspection
KW - Multi-sensors
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-625107
DO - https://doi.org/10.58286/29868
SN - 1435-4934
VL - 29
SP - 1
EP - 8
AN - OPUS4-62510
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Zia, Ghezal Ahmad Jan
A1 - Valdestilhas, Andre
A1 - Moreno Torres, Benjami
A1 - Kruschwitz, Sabine
T1 - Leveraging large language models for automated knowledge graphs generation in non-destructive testing
N2 - This paper presents an innovative approach for the automatic generation of Knowledge Graphs (KGs) from heterogeneous scientific articles in the domain of Non-Destructive Testing (NDT) applied to building materials.
Our methodology leverages large language models (LLMs) to extract and semantically relate concepts from diverse sources. We developed material-specific agents for concrete, wood, steel, and bricks, each equipped with a curated glossary of terms to ensure domain accuracy. These agents process PDF documents, extracting relevant information on deterioration mechanisms, physical changes, and applicable NDT methods. The extracted data is then normalized, validated, and structured into a Neo4j graph database, forming a comprehensive KG. Our results demonstrate the system’s ability to automatically discover and represent intricate relationships between materials, deterioration mechanisms, physical changes, and NDT techniques. The generated KG successfully captures complex interactions, such as the applicability of specific NDT methods to various materials under different deterioration conditions. This work not only highlights the potential of KGs in enhancing knowledge discovery and representation in NDT research but also provides a scalable framework for extending this approach to other scientific domains.
T2 - SeMatS 2024 - The 1st International Workshop on Semantic Materials Science
CY - Amsterdam, The Netherlands
DA - 17.09.2024
KW - Materials science and engineering
KW - Large language model
KW - Linked open data
KW - Data interoperability
KW - RDF
KW - Semantic web
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624597
DO - https://doi.org/10.5281/zenodo.13834164
SN - 1613-0073
N1 - Serientitel: CEUR workshop proceedings – Series title: CEUR workshop proceedings
VL - 3760
SP - 101
EP - 110
PB - RWTH Aachen
CY - Aachen
AN - OPUS4-62459
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Strobl, Dominic
A1 - Unger, Jörg F.
A1 - Ghnatios, C.
A1 - Robens-Radermacher, Annika
T1 - PGD in thermal transient problems with a moving heat source: A sensitivity study on factors affecting accuracy and efficiency
N2 - Thermal transient problems, essential for modeling applications like welding and additive metal manufacturing, are characterized by a dynamic evolution of temperature. Accurately simulating these phenomena is often computationally expensive, thus limiting their applications, for example for model parameter estimation or online process control. Model order reduction, a solution to preserve the accuracy while reducing the computation time, is explored. This article addresses challenges in developing reduced order models using the proper generalized decomposition (PGD) for transient thermal problems with a specific treatment of the moving heat source within the reduced model. Factors affecting accuracy, convergence, and computational cost, such as discretization methods (finite element and finite difference), a dimensionless formulation, the size of the heat source, and the inclusion of material parameters as additional PGD variables are examined across progressively complex examples. The results demonstrate the influence of these factors on the PGD model’s performance and emphasize the importance of their consideration when implementing such models. For thermal example, it is demonstrated that a PGD model with a finite difference discretization in time, a dimensionless representation, a mapping for a moving heat source, and a spatial domain non-separation yields the best approximation to the full order model.
KW - Additive manufacturing
KW - Mapping for unseparable load
KW - Model order reduction (MOR)
KW - Thermal transient problem
KW - Sensitivity analysis
KW - Proper generalized decomposition (PGD)
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598001
DO - https://doi.org/10.1002/eng2.12887
VL - 6
IS - 11
SP - 1
EP - 22
PB - John Wiley & Sons Ltd.
CY - Berlin
AN - OPUS4-59800
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Agrawal, A.
A1 - Tamsen, E.
A1 - Unger, Jörg F.
A1 - Koutsourelakis, P-S
T1 - From concrete mixture to structural design—a holistic optimization procedure in the presence of uncertainties
N2 - We propose a systematic design approach for the precast concrete industry to promote sustainable construction practices. By employing a holistic optimization procedure, we combine the concrete mixture design and structural simulations in a joint, forward workflow that we ultimately seek to invert. In this manner, new mixtures beyond standard ranges can be considered. Any design effort should account for the presence of uncertainties which can be aleatoric or epistemic as when data are used to calibrate physical models or identify models that fill missing links in the workflow. Inverting the causal relations established poses several challenges especially when these involve physicsbased models which more often than not, do not provide derivatives/sensitivities or when design constraints are present. To this end, we advocate Variational Optimization, with proposed extensions and appropriately chosen heuristics to overcome the aforementioned challenges. The proposed approach to treat the design process as a workflow, learn the missing links from data/models, and finally perform global optimization using the workflow is transferable to several other materials, structural, and mechanical problems. In the present work, the efficacy of the method is exemplarily illustrated using the design of a precast concrete beam with the objective to minimize the global warming potential while satisfying a number of constraints associated with its load-bearing capacity after 28 days according to the Eurocode, the demolding time as computed by a complex nonlinear finite element model, and the maximum temperature during the hydration.
KW - Black-box optimization under uncertainty
KW - Mix design
KW - Performance oriented design
KW - Precast concrete
KW - Probabilistic machine learning
KW - Sustainable material design
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615443
DO - https://doi.org/10.1017/dce.2024.18
VL - 5
IS - e20
SP - 1
EP - 32
PB - Cambridge University Press
CY - England
AN - OPUS4-61544
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Strangfeld, Christoph
A1 - Schönsee, Eric
A1 - Jeyifous, Olubunmi Anthony
A1 - Izanlu, Morteza
A1 - Hüsken, Götz
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - In situ Prozessüberwachung und Qualitätskontrolle bei der additiven Fertigung von Betonbauteilen
N2 - In der additiven Fertigung von Beton wird kontinuierlich Material gemischt und verarbeitet. Dies erfordert eine kontinuierliche in situ Prozessüberwachung und Qualitätskontrolle. An der BAM wurde ein 3D-Betondrucker aufgebaut, der eine umfängliche Prozessüberwachung ermöglicht. Druck-, Temperatur- und Feuchtesensoren in der Pumpe und im Fördersystem erlauben ein kontinuierliches Monitoring des Frischbetons, während ein Laserlinienscanner am Druckkopf unmittelbar die gedruckte Ist-Kontur verfolgt. Die so gewonnenen Daten können Grundlage für die Erarbeitung von Normen für die additive Fertigung von Betonbauteilen sein und somit deren Standsicherheit gewährleisten.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - In situ
KW - Prozessüberwachung
KW - Additive Fertigung
KW - Betonbauteil
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613064
SN - 978-3-9818564-7-7
SP - 138
EP - 146
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61306
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Rübner, Katrin
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Vom Bauschutt zur leichten Gesteinskörnung
N2 - Leichte Gesteinskörnungen können ressourcenschonend aus heterogenen und feinkörnigen Bau- und Abbruchabfällen in einem mehrstufigen Prozess durch thermische oder hydrothermale Stoffumwandlung hergestellt werden. Ihre Anwendung erfolgt in Leichtbetonen und Leichtmörteln, als Schüttung im Garten und Landschaftsbau oder auch als Filter- und Speichermaterial. In zahlreichen Forschungsprojekten wurden die Herstellungsprozesse entwickelt, die Materialeigenschaften optimiert und unterschiedliche Applikationen untersucht. In diesem Beitrag wird zusammenfassend über dieser Forschungsarbeiten berichtet.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Bauschutt
KW - Gesteinskörnung
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613105
SN - 978-3-9818564-7-7
SP - 70
EP - 77
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61310
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Cook, Jake
A1 - Tonon, Chiara
A1 - Stohl, Leonie
A1 - von Werder, Julia
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Assessment of concrete bioreceptivity and model organism performance for use in algal biofilm green facade systems
N2 - Elevated temperatures and high levels of air pollution in urban environments pose a significant threat to the health and life quality of inhabitants of these areas. This research aims to address these challenges by developing green façade systems using micro-algal biofilms. Both material and biological properties are assessed to optimise biofilm performance and durability. Cementitious samples with different pH levels and varying nutrient compositions are tested in combination with model microorganisms. Organism growth, health and adhesion are monitored over a 3-month period under controlled laboratory conditions.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Concrete bioreceptivity
KW - Model organism performance
KW - Algal biofilm
KW - Algal biofilm green facade systems
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613114
SN - 978-3-9818564-7-7
SP - 159
EP - 166
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61311
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Robens-Radermacher, Annika
A1 - Saif-Ur-Rehman,
A1 - Wolf, Christoph
A1 - Kujath, Cezary
A1 - He, Yuxiang
A1 - Mezhof, Alexander
A1 - Hüsken, Götz
A1 - Jeyifous, Olubunmi Anthony
A1 - Unger, Jörg F.
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Modellierung und Simulation von 3D Betondruck – Design- und Prozessoptimierung
N2 - Der 3D Betondruck ermöglicht die effiziente und ressourcenschonendere Herstellung maßgeschneiderter Betonstrukturen. Trotz des großen Potentials gibt es bisher keine einheitlichen Normen und Standards für den sicheren und robusten 3D Betondruck. Der Beitrag zeigt das Potential numerischer Methoden und Modelle zur effizienten und ressourcenschonenden Design- und Prozessoptimierung des 3D Betondrucks. Dazu werden die aktuellen Forschungsarbeiten im Bereich der Entwicklung robuster und zuverlässiger numerischer Zwillinge, geeigneter Optimierungstools sowie digitaler Workflows diskutiert.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Modellierung
KW - Simulation
KW - 3D Betondruck
KW - Designoptimierung
KW - Prozessoptimierung
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613023
SN - 978-3-9818564-7-7
SP - 132
EP - 137
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61302
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Andrés Arcones, Daniel
A1 - Unger, Jörg F.
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Modell- und Parameterunsicherheiten am Beispiel eines digitalen Brückenzwillings
N2 - Digitale Zwillinge bieten wertvolle Einblicke in das Verhalten von Bauwerken und ermöglichen eine fundierte Entscheidungsfindung. Durch den Einsatz von Simulationen, die auf physikalischen Gesetzen beruhen, ist es möglich, Vorhersagen über die Struktur auf der Grundlage zukünftiger oder hypothetischer Situationen zu treffen. Die Verwendung solcher Simulationen impliziert jedoch eine Reihe von Annahmen und Vereinfachungen, die unvermeidbare Fehler in die Vorhersagen einbringen. Die Quantifizierung dieser Unsicherheiten ist der Schlüssel für den Einsatz zuverlässiger digitaler Zwillinge von Brücken.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Modellunsicherheit
KW - Parameterunsicherheit
KW - Digitaler Brückenzwilling
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613013
SN - 978-3-9818564-7-7
SP - 218
EP - 223
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61301
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Hüsken, Götz
A1 - Jeyifous, Olubunmi Anthony
A1 - Schönsee, Eric
A1 - Strangfeld, Christoph
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Beitrag zur Beurteilung der Wiederholbarkeit additiv gedruckter Betonbauteile
N2 - Die additive Fertigung von Betonbauteilen, auch bekannt als 3D-Betondruck, ist eine Technologie, die im letzten Jahrzehnt aufgrund ihrer finanziellen und ökologischen Vorteile als nachhaltige Fertigungstechnologie viel Aufmerksamkeit erhalten hat. Obwohl die Vorteile der additiven Fertigung bereits durch zahlreiche Forschungs- und Demonstrationsprojekte gezeigt wurden, ist die Qualitätskontrolle während des Druckens äußerst anspruchsvoll und wird auch aufgrund fehlender harmonisierter Normen kaum angewendet. Aufgrund des kontinuierlichen Mischprozesses beim 3D-Betondruck ist es unmöglich Schwankungen des Trockenmörtels oder des Wassergehalts auszuschließen. Daher ist eine einzelne Stichprobe nicht mehr repräsentativ für das gesamte Bauteil und ein während des Druckens in einer Schicht auftretender Fehler kann die Integrität der gesamten Struktur beeinträchtigen. In diesem Beitrag werden die Ergebnisse eines als Fachwerkstruktur konzipierten Bogens, der unter vergleichbaren Randbedingungen mehrmals mit einem 3D-Betonextrusionsdrucker gedruckt wurde, vorgestellt. Jeder Bogen wurde auf seine mechanische Festigkeit und sein Tragverhalten geprüft. Die Ergebnisse der mechanischen Prüfungen der gedruckten Bögen werden mit Materialdaten aus klassischen Materialprüfungen verglichen und hinsichtlich ihrer statistischen Signifikanz diskutiert.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Additiv gedrucktes Betonbauteil
KW - Beurteilung
KW - Wiederholbarkeit
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613043
SN - 978-3-9818564-7-7
SP - 126
EP - 131
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61304
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Pirskawetz, Stephan
A1 - Trattnig, H.
A1 - Boehm, C.
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Spanndrahtbrüche und ihr digitaler akustischer Zwilling
N2 - Die Planung eines Monitorings von Spanndrahtbrüchen mit Schallemissionsanalyse erfordert viel Erfahrung und setzt eine akustische Analyse der Spannbetonstruktur voraus. Eine akustische Simulation der Struktur unterstützt die Optimierung der Sensoranordnung und erhöht die Zuverlässigkeit der Drahtbrucherkennung durch die Fusion von Simulations- und Messergebnissen in einer Datenbank. Künftig können Baulastträger und Monitoringanbieter von standardisierten – FAIR-en – akustischen Daten profitieren.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Spanndrahtbruch
KW - Digitaler akustischer Zwilling
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613038
SN - 978-3-9818564-7-7
SP - 224
EP - 229
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61303
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Stohl, Leonie
A1 - Cook, Jake
A1 - von Werder, Julia
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Bioreceptive concrete surfaces: Understanding material-biology interactions for façade greening
N2 - The climate crisis has led to a growing demand for environmentally oriented approaches in the construction industry, including not only eco-friendly materials, but also the greening of urban spaces. Microbial facade greening with algae is a novel concept based on the inherent bioreceptive properties of different building materials. This study focuses on the influence of physical material properties on biofilm formation. Differently textured samples from the same UHPC mix were produced and their roughness and water absorption documented. The samples were then weathered under laboratory conditions to observe material-algae interactions.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Bioreceptive
KW - Material-biology Interaction
KW - Façade greening
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613096
SN - 978-3-9818564-7-7
SP - 153
EP - 158
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61309
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Weise, Frank
A1 - Kühnel, Alena
A1 - Fladt, Matthias
A1 - Stelzner, Ludwig
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Dauerhaftigkeit von Betonfahrbahndecken im deutschen Bundesautobahnnetz
N2 - Die Dauerhaftigkeit der Betondecke und deren Oberflächentexturierung bestimmen maßgebend das Ge-brauchsverhalten von Betonfahrbahnen. Der Beitrag zeigt die Leistungsfähigkeit der Innenhydrophobierung als neuartige AKR-Vermeidungsstrategie zur Sicherstellung der geplanten, normativen Nutzungsdauer, auch unter Verwendung grenzwertig alkaliempfindlicher Gesteinskörnungen, auf. Zusätzlich wird eine neuartige Prüfmethodik zur in situ Verfolgung der 3D-Texturveränderungen auf einem erneuerten BAB-Abschnitt mit Grindingtextur vorgestellt. Diese beeinflussen maßgebend die Griffigkeit und die Reifen-Fahrbahn-Geräusche.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Betonfahrbahnen
KW - Alkali-Kieselsäure-Reaktion
KW - Innenhydrophobierung
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613184
SN - 978-3-9818564-7-7
SP - 232
EP - 243
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61318
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Recknagel, Christoph
A1 - Weigel, Sandra
A1 - Hoppe, Johannes
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Dauerhafte Funktionsfähigkeit von Bauwerksfugen - Das performance concept in der Abdichtungstechnik von Betonfahrbahnen
N2 - Verlässliche Funktionsfähigkeit und planbare Lebensdauerzyklen sind entscheidend für die Weiterentwicklung der Betonbauweise im Straßenbau. Aus Forschungsergebnissen zur Fugenproblematik in hochbeanspruchten Betonfahrbahnen unter Diskussion regelungsspezifischer Erfordernisse erfolgt ein Plädoyer für eine funktionsanalytische Untersuchung von Fugensystemen. Mit aktuellen Projekten werden die Datengrundlage zu maßgebenden Einwirkungen und eine innovative versuchstechnische Infrastruktur als methodische Voraussetzungen zur Erhöhung zuverlässiger Funktionsfähigkeit von Bauwerksfugen bereitgestellt.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Betonfahrbahnen
KW - Bauwerksfugen
KW - Abdichtungstechnik von Betonfahrbahnen
KW - SensoJointField
KW - INFUKON
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613207
SN - 978-3-9818564-7-7
SP - 244
EP - 252
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61320
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Weigel, Sandra
A1 - Recknagel, Christoph
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Ein Ausblick: Alternative Bindemittel für bitumenhaltige Materialien
N2 - Im Straßen- und Ingenieurbau sind neben dem Baustoff Beton auch bitumenhaltige Materialien in Flächenab-dichtungen, Dehnfugenkonstruktionen und Asphaltbelägen von entscheidender Bedeutung. Die bestehende Erdölabhängigkeit dieser Materialien fordert jedoch ein dringendes Umdenken, wobei langfristig die Substitu-tion des Bitumens durch nachhaltige, biobasierte Alternativmaterialien angestrebt werden sollte. Durch eine partielle Substitution wäre zudem bereits kurz- bis mittelfristig eine Reduzierung der Erdölabhängigkeit mög-lich, wobei sich z.B. Rückstände der Mikroalgenaufbereitung oder Lignin als Substitutionsprodukte eignen.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Alternative
KW - Bindemittel
KW - Bitumenhaltige Materialien
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613138
SN - 978-3-9818564-7-7
SP - 167
EP - 174
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61313
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Pittrich, Tim
A1 - Stelzner, Ludwig
A1 - Weise, Frank
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Tunnelbrand – Abplatzverhalten von normalfesten Betonen mit verschiedenen klinkereffizienten Zementen
N2 - Zur Verminderung der CO2-Emissionen der Bauindustrie gewinnen klinkereffiziente Zemente immer mehr an Bedeutung und werden vermehrt in Ingenieurbauwerken eingesetzt. Das brandinduzierte Abplatzverhalten von Betonen mit diesen Zementen ist allerdings nur bedingt bekannt und ist u.a. im Tunnelbau von hoher Bedeutung. Im Zuge dessen, wurden normalfeste Betone mit vier verschiedenen Zementen (CEM I, CEM II/A-LL, CEM III/A und CEM II/B-Q) auf ihr brandinduziertes Abplatzverhalten untersucht. Die Ergebnisse zeigen, dass Betone mit klinkereffizienten Zementen zu stärkeren Abplatzungen neigen.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Verminderung CO2-Emissionen
KW - Brandinduziertes Abplatzverhalten
KW - Klinkereffiziente Zemente
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613215
SN - 978-3-9818564-7-7
SP - 253
EP - 262
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61321
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Bednarska, Dalia
A1 - von Werder, Julia
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Modification of clay-based materials with a novel geopolymer: potential application towards water-resistance
N2 - Earth is probably the most eco-friendly building material. However, since earthen materials dissolve in water easily their application is limited. The presented manuscript aims to verify the usefulness of a one-part geo- polymer developed at BAM as a stabilizing agent for earthen mortars. The experimental study encompasses water-resistance, compressive strength, linear shrinkage, water vapour permeability and microstructural anal- ysis of the reference and the modified earthen plaster. The presented results show that the modification visibly affects the properties of the initial material providing its water-resistance.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Clay-based materials
KW - Water-resistance
KW - Novel geopolymer
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613150
SN - 978-3-9818564-7-7
SP - 94
EP - 101
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61315
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Hille, Falk
A1 - Herrmann, Ralf
A1 - Schneider, Ronald
A1 - Pitters, S.
A1 - Wedel, F.
A1 - Hindersmann, I.
T1 - Developing a guideline for structural health monitoring of road bridges in Germany
N2 - In recent years, Structural Health Monitoring (SHM) has become a useful and increasingly widely used tool for supporting lifetime extensions of existing bridges with known structural deficiencies or indications of potentially critical damages or damage processes.
At the same time, methods and tools are emerging, which enable monitoring-informed predictive maintenance of new and existing bridges based on digital twins. The monitoring process – starting from the definition of monitoring actions and ending with decisions based on monitoring outcomes – is complex and requires expertise in structural engineering, operation and maintenance of bridges, metrology, and data analytics. To support German road authorities, engineering consultancies, building contractors and other stakeholders of the bridge management, the Federal Highway Research Institute (BASt) has initiated the development of a new guideline for applying SHM as part of the management of road bridges. The guideline will present various use cases and for each identified use case, it will propose a proven monitoring scheme. In addition, the guideline will provide guidance on assessing the benefits of SHM as well as a common approach to managing monitoring data as a systematic basis for integrating monitoring data in the bridge management. This contribution discusses the motivation, objectives, and scope of the guideline, describes its use case centric structure and outlines the proposed data management.
T2 - IABMAS 2024
CY - Kopenhagen, Danmark
DA - 24.06.2024
KW - Guideline
KW - Structural health monitoring
KW - Road bridges
KW - Infrastructure
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613947
SN - 978-1-032-77040-6
DO - https://doi.org/10.1201/9781003483755-236
SP - 2009
EP - 2017
PB - CRC Press
AN - OPUS4-61394
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Neugum, Tim
A1 - Stelzner, Ludwig
A1 - Häßler, Dustin
A1 - Hothan, Sascha
A1 - Zehfuß, J.
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Feuerwiderstand gezwängter Stahlbetonstützen
N2 - Bei realen Brandereignissen stellen sich in der Regel mechanische und thermische Randbedingungen ein, die deutlich von denen in präskriptiven, bauteilorientierten Brandprüfungen abweichen. Beispielsweise werden Interaktionen der brandbeanspruchten Bauteile mit dem umgebenden Tragwerk und daraus resultierende Zwangsbeanspruchungen bei konventionellen Brandprüfungen nicht berücksichtigt. Mit Hilfe der Substrukturtechnik kann das Verhalten einer Stütze im Brandfall unter Berücksichtigung der Interaktion mit dem umgebenden Tragwerk untersucht werden.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Brandprüfungen
KW - Substrukturtechnik
KW - Zwangsbeanspruchungen
KW - Brandbeanspruchung
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613249
SN - 978-3-9818564-7-7
SP - 270
EP - 277
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61324
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Thiele, Marc
A1 - Herrmann, Ralf
A1 - Degener, Sebastian
A1 - Pirskawetz, Stephan
A1 - Loewe, Anna
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Monitoring an Türmen von Onshore Windenergieanlagen in Betonbauweise im Hinblick auf Ermüdung
N2 - Der Beitrag stellt das Messkonzept sowie dessen Umsetzung für ein umfassendes Monitoringsystem an einer onshore Windenergieanlage mit einem Hybridturm vor. Dieses ist Bestandteil des Forschungsvorhabens Win-ConFat – Structure, welches neben der Validierung geeigneter Sensorik auch die Bewertung des Zustands und der möglichen Restlebensdauer der ermüdungsbeanspruchten Betonstruktur zum Ziel hat. Neben dem Monitoringsystem werden erste Messergebnisse aus den Betriebsdaten sowie vom Verhalten der Turmstruktur vorgestellt.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Monitoring
KW - Windenergieanlage und Hybridturm
KW - Ermüdung
KW - WinConFat – Structure
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613276
SN - 978-3-9818564-7-7
SP - 286
EP - 293
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61327
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Hering, Marcus
A1 - Fiedler, Georg
A1 - Schubert, T.
A1 - Hille, Falk
A1 - Hüsken, Götz
A1 - Beckmann, B.
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Großmaßstäbliche Impaktversuche mit Stahlbetonplatten – Konzeptionierung und Vorbereitung
N2 - Seit 1977 ist der Flugzeugabsturz ein wesentliches Belastungsszenario bei der Auslegung von Kernkraftwerken. Zur Untersuchung dieses Szenarios wurden umfassende Studien durchgeführt, welche die Reaktion von Stahlbetonkonstruktionen unter Stoßbelastung analysieren. Da großmaßstäbliche Experimente teuer und aufwendig sind, gewinnen skalierte Versuche zunehmend an Bedeutung. Im Rahmen eines Forschungsprojekts der TU Dresden und der BAM wurden Grundlagen für skalierte Impaktversuche im großen Maßstab geschaffen, um die Übertragbarkeit vom Labor- auf Realmaßstab zu ermöglichen.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Fallturm
KW - Impakt
KW - Stahlbetonbauteile
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613257
SN - 978-3-9818564-7-7
SP - 278
EP - 285
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61325
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Deresse, N. E.
A1 - Thiele, Marc
A1 - Pirskawetz, Stephan
A1 - Sarem, M.
A1 - Francois, St.
A1 - Verstrynge, E.
T1 - Evaluation of Concrete Fatigue Damage with Elastic Wave-based Measurement Techniques
N2 - The fatigue damage evolution and the fatigue life of quasi-brittle materials such as concrete are not yet completely understood. Accordingly to get better insights, researchers have recently been incorporating advanced measuring techniques in their fatigue experiments. In this research, acoustic emission techniques (AET), active ultrasonic, and deformation measurements are used to track the damage evolution of concrete samples subjected to fatigue loading. The samples are subjected to constant amplitude and stepwise fatigue loading in Brazilian splitting test set-ups. Initially, a good agreement is observed between the deformation and the ultrasonic measurements in capturing the crack propagation during Brazilian splitting tests. The three fatigue damage phases could be identified with all of the three techniques. The Phase II damage rates quantified by deformation measurements and AET in stepwise fatigue tests were used to predict the number of cycles to failure at various stress
levels. The predictions were validated using the number of cycles to failure of the constant amplitude fatigue tests.
T2 - 36th Conference of the European Working Group on Acoustic Emission
CY - Potsdam, Germany
DA - 18.09.2024
KW - Concrete
KW - Acoustic emission
KW - Ultrasonic testing
KW - Fatigue
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615677
DO - https://doi.org/10.58286/30228
SN - 1435-4934
VL - 29
IS - 10
SP - 1
EP - 10
PB - NDT.net
AN - OPUS4-61567
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Stelzner, Ludwig
A1 - Eiz Eddin, Ahmad
A1 - Häßler, Dustin
A1 - Hothan, Sascha
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Zum Feuerwiderstand von filigranen Deckenelementen aus vorgespanntem Carbonbeton
N2 - Der Einsatz von hoch zugbeanspruchbarem und korrosionsbeständigem Carbongelege anstelle herkömmlichen Spannstahls ermöglicht es Beton vorzuspannen und gleichzeitig die Betondeckung auf ein für den Verbund nötiges Minimum zu reduzieren. Der Wechsel von massiven zu filigranen Bauteilen führt in der Regel aufgrund der geringeren thermischen Masse zu einer Abnahme des Feuerwiderstandes. Der Beitrag stellt Versuchsergebnisse zum Abplatzverhalten von Carbonbeton vor, die im Rahmen des Verbundvorhabens „Vorgespannte Carbonbetondecken mit reduzierten Querschnitten“ (CaPreFloor) erzielt wurden.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Feuerwiderstand
KW - Carbonbeton
KW - Abplatzverhalten
KW - CaPreFloor
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613221
SN - 978-3-9818564-7-7
SP - 263
EP - 269
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61322
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Krüger, Miriam E.
A1 - Hilbig, Harald
A1 - Stelzner, Ludwig
A1 - Machner, Alisa
T1 - Effect of the chemical composition of synthetic alkali-silica gels on their structure, swelling behavior and water uptake
N2 - For alkali-silica reaction (ASR) gels, the relationship between swelling expansion, structure and chemical composition, particularly the effect of aluminum, remains unknown. This study investigates the structure, swelling expansion and associated water uptake of synthetic ASR gels with various Al/Si (0–0.1) and Ca/Si (0.1–0.4) ratios. The results show that aluminum incorporated into the gel structure reduces the overall swelling expansion and the leaching of silicate species during the swelling test. Moreover, they revealed that water in the Al-ASR gels is more tightly bound, reducing the overall water uptake compared to the Al-free ASR gels. Additionally, there is a linear correlation between the maximal swelling results and the ASR gel composition.
However, no direct correlation emerged between the amount of water uptake and the free swelling of the ASR gels, which indicates that other factors, like the type of water bonding and pore size of the gels, are decisive for the swelling mechanism.
KW - Concrete
KW - Alkali-silica reaction (ASR)
KW - Durability
KW - 1H NMR relaxometry
KW - 29Si NMR
KW - 27Al NMR
KW - FTIR
KW - Al-ASR gel
KW - Swelling test
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-624268
DO - https://doi.org/10.1016/j.cemconres.2024.107596
VL - 184
SP - 1
EP - 18
PB - Elsevier B.V.
AN - OPUS4-62426
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Andrés Arcones, Daniel
A1 - Weise, M.
A1 - Koutsourelakis, P-S.
A1 - Unger, Jörg F.
T1 - Bias Identification Approaches for Model Updating of Simulation-based Digital Twins of Bridges
N2 - Simulation-based digital twins of bridges have the potential not only to serve as monitoring devices of the current state of the structure but also to generate new knowledge through physical predictions that allow for better-informed decision-making. For an accurate representation of the bridge, the underlying models must be tuned to reproduce the real system. Nevertheless, the necessary assumptions and simplifications in these models irremediably introduce discrepancies between measurements and model response. We will show that quantifying the extent of the uncertainties introduced through the models that lead to such discrepancies provides a better understanding of the real system, enhances the model updating process, and creates more robust and trustworthy digital twins. The inclusion of an explicit bias term will be applied to a representative demonstrator case based on the thermal response of the Nibelungenbrücke of Worms. The findings from this work are englobed in the initiative SPP 100+, whose main aim is the extension of the service life of structures, especially through the implementation of digital twins.
T2 - EWSHM 2024 11th European Workshop on Structural Health Monitoring
CY - Potsdam, Germany
DA - 10.06.2024
KW - Digital Twins
KW - Model Bias
KW - SPP100+
KW - Bridge Monitoring
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-622522
DO - https://doi.org/10.58286/30524
SN - 2941-4989
IS - 12
SP - 1
EP - 10
PB - NDT.net GmbH & Co. KG
CY - Mayen, Germany
AN - OPUS4-62252
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Klewe, Tim
A1 - Strangfeld, Christoph
A1 - Ritzer, Tobias
A1 - Kruschwitz, Sabine
T1 - Classification of Practical Floor Moisture Damage Using GPR - Limits and Opportunities
N2 - Machine learning in non-destructive testing (NDT) offers significant potential for efficient daily data analysis and uncovering previously unknown relationships in persistent problems. However, its successful application heavily depends on the availability of a diverse and well-labeled training dataset, which is often lacking, raising questions about the transferability of trained algorithms to new datasets. To examine this issue closely, the authors applied classifiers trained with laboratory Ground Penetrating Radar (GPR) data to categorize on-site moisture damage in layered building floors. The investigations were conducted at five different locations in Germany. For reference, cores were taken at each measurement point and labeled as (i) dry, (ii) with insulation damage, or (iii) with screed damage. Compared to the accuracies of 84 % to 90 % within the laboratory training data (504 B-Scans), the classifiers achieved a lower overall accuracy of 53 % for on-site data (72 B-Scans). This discrepancy is mainly attributable to a significantly higher dynamic of all signal features extracted from on-site measurements compared to laboratory training data. Nevertheless, this study highlights the promising sensitivity of GPR for identifying individual damage cases. In particular the results showing insulation damage, which cannot be detected by any other non-destructive method, revealed characteristic patterns. The accurate interpretation of such results still depends on trained personnel, whereby fully automated approaches would require a larger and diverse on-site data set. Until then, the findings of this work contribute to a more reliable analysis of moisture damage in building floors using GPR and offer practical insights into applying machine learning to non-destructive testing for civil engineering (NDT-CE).
KW - GPR
KW - Material moisture
KW - Building floor
KW - Machine Learning
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607932
DO - https://doi.org/10.1007/s10921-024-01111-7
SN - 0195-9298
VL - 43
IS - 3
SP - 1
EP - 16
PB - Springer Science and Business Media LLC
AN - OPUS4-60793
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Schönsee, Eric
A1 - Jeyifous, Olubunmi Anthony
A1 - Strangfeld, Christoph
A1 - Hüsken, Götz
T1 - Investigations on multi-sensor data for monitoring volume flow during the printing process
N2 - Extrusion based 3D concrete printing (3DCP) is a growing technology because of its high potential for automating construction and the new possibilities of design. In conventional construction methods, a sample is taken to be representative for one material batch. However, in 3DCP continuous mixing is used which results in variations during the mixing process. Therefore, one sample is not representative for the entire structure. This leads to the necessity of continuous and real-time process monitoring.
This study focuses on the variations of pressure and temperature which are caused by changes in the material due to the ongoing mixing process. Changes in material, which is transported downstream, are influencing sensor signals in different positions with a time delay. In the following, the data is analysed to investigate if the changing material and the so caused change in pressure can be used to calculate volume flow.
T2 - Digital Concrete 2024
CY - Munich, Germany
DA - 04.09.2024
KW - Additive manufacturing
KW - In-line Monitoring
KW - Volume Flow
KW - Process Control
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:gbv:084-2024081513042
DO - https://doi.org/10.24355/dbbs.084-202408151304-0
SP - 1
EP - 3
AN - OPUS4-61001
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bartels, Jan-Hauke
A1 - Xu, Ronghua
A1 - Kang, Chongjie
A1 - Herrmann, Ralf
A1 - Marx, Steffen
T1 - Experimental Investigation on the Transfer Behavior and Environmental Influences of Low-Noise Integrated Electronic Piezoelectric Acceleration Sensors
N2 - Acceleration sensors are vital for assessing engineering structures by measuring properties like natural frequencies. In practice, engineering structures often have low natural frequencies and face harsh environmental conditions. Understanding sensor behavior on such structures is crucial for reliable masurements. The research focus is on understanding the behavior of acceleration sensors in harsh environmental conditions within the low-frequency acceleration range. The main question is how to distinguish sensor behavior from structural influences to minimize errors in assessing engineering structure conditions. To investigate this, the sensors are tested using a long-stroke calibration unit under varying temperature and humidity conditions. Additionally, a mini-monitoring system configured with four IEPE sensors is applied to a small-scale support structure within a climate chamber. For the evaluation, a signal-energy approach is employed to distinguish sensor behavior from structural behavior. The findings show that IEPE sensors display temperature-dependent nonlinear transmission behavior within the low-frequency acceleration range, with humidity having negligible impact. To ensure accurate engineering structure assessment, it is crucial to separate sensor behavior from structural influences using signal energy in the time domain. This study underscores the need to compensate for systematic effects, preventing the underestimation of vibration energy at low temperatures and overestimation at higher temperatures when using IEPE sensors for engineering structure monitoring.
KW - Acceleration sensors
KW - Environmental influence
KW - IEPE
KW - Structural Health Monitoring
KW - Low-frequency shaker
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594623
UR - https://www.mdpi.com/2673-8244/4/1/4/
DO - https://doi.org/10.3390/metrology4010004
SN - 2673-8244
VL - 4
IS - 1
SP - 46
EP - 65
PB - MDPI
CY - Basel
AN - OPUS4-59462
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Klimek, André
A1 - Stelzner, Ludwig
A1 - Hothan, Sascha
A1 - Zehfuß, Jochen
T1 - Influence of thermal strain on concrete spalling
N2 - Understanding the susceptibility to spalling of concrete members in case of fire is important to evaluate the residual load-bearing capacity. The investigations of the spalling phenomenon of a concrete mixture using real scale members are necessary but expensive to carry out. Reducing the specimen size leads to an increase of boundary effects that can result in a reduced spalling or absence of spalling. In this study, fire tests were carried out on unrestrained, single-sided exposed, cuboid shaped specimens (0.6 m x 0.6 m x 0.29 m) as well as unrestrained and steel ring restrained cylindrical specimens (Ø = 0.47 m, h = 0.29 m), which induce different boundary conditions. These fire tests were carried out on two ordinary concrete mixtures. The two mixtures differ only in the type of aggregates (quartz gravel and basalt grit) and were used to investigate the influence of the thermal expansion of the aggregate on the spalling behaviour of the concrete. The results show a significant increase of
the spalling depth due to the restrained thermal expansion achieved by the applied steel rings. Additionally, the type of aggregate has a direct influence on the spalling behaviour of a concrete mixture. The reduction of the boundary effects by the steel rings recreate the test conditions in the centre of a large concrete member. Thus, this type of specimen is suitable to determine the susceptibility to spalling of a material (screening-tests) as preliminary investigations to full scale fire tests.
KW - Spalling
KW - Concrete
KW - Fire test
KW - Restraint
KW - Screening test
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593350
DO - https://doi.org/10.1617/s11527-023-02274-x
VL - 57
SP - 1
EP - 14
PB - Springer
AN - OPUS4-59335
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Glienke, R.
A1 - Kalkowsky, F.
A1 - Hobbacher, A. F.
A1 - Holch, A.
A1 - Thiele, Marc
A1 - Marten, F.
A1 - Kersten, R.
A1 - Henkel, K.-M.
T1 - Evaluation of the fatigue resistance of butt‑welded joints in towers of wind turbines - A comparison of experimental studies with small scale and component tests as well as numerical based approaches with local concepts
N2 - Wind turbines are exposed to a high number of load cycles during their service lifetime. Therefore, the fatigue strength verification plays an important role in their design. In general, the nominal stress method is used for the fatigue verification of the most common used butt-welded joints. The Eurocode 3 part 1–9 is the current design standard for this field of application. This paper presents recent results of fatigue tests on small-scaled specimens and large components with transverse butt welds to discuss the validity of the FAT-class. Furthermore, results from numerical simulations for the verification with the effective notch stress and the crack propagation approach are used for comparison. Based on the consistency between the numerical results and the fatigue tests, the influence of the seam geometry on the fatigue resistance was investigated. Finally, a prediction of the fatigue strength of butt-welded joints with plate thicknesses up to 80 mm was carried out.
KW - Transverse butt weld
KW - Weld imperfections
KW - Wind turbine tower
KW - Fatigue strength
KW - Local approaches
KW - Large components
KW - Wind energy
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596648
DO - https://doi.org/10.1007/s40194-023-01630-3
SN - 1878-6669
SP - 1
EP - 26
PB - Springer
CY - Berlin
AN - OPUS4-59664
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bühling, Benjamin
A1 - Maack, Stefan
A1 - Strangfeld, Christoph
T1 - Fluidic Ultrasound Generation for Non‐Destructive Testing
N2 - AbstractAir‐coupled ultrasonic testing (ACU) is a pioneering technique in non‐destructive testing (NDT). While contact testing and fluid immersion testing are standard methods in many applications, the adoption of ACU is progressing slowly, especially in the low ultrasonic frequency range. A main reason for this development is the difficulty of generating high amplitude ultrasonic bursts with equipment that is robust enough to be applied outside a laboratory environment. This paper presents the fluidic ultrasonic transducer as a solution to this challenge. This novel aeroacoustic source uses the flow instability of a sonic jet in a bistable fluidic switch to generate ultrasonic bursts up to 60 kHz with a mean peak pressure of 320 Pa. The robust design allows operation in adverse environments, independent of the operating fluid. Non‐contact through‐transmission experiments are conducted on four materials and compared with the results of conventional transducers. For the first time, it is shown that the novel fluidic ultrasonic transducer provides a suitable acoustic signal for NDT tasks and has potential of furthering the implementation of ACU in industrial applications.This article is protected by copyright. All rights reserved
KW - Aeroacoustics
KW - Air-coupled ultrasound
KW - Fluidics
KW - Harsh environment
KW - Laser Doppler vibrometer
KW - Non-destructive testing
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594273
DO - https://doi.org/10.1002/adma.202311724
SN - 0935-9648
SP - 1
EP - 14
PB - Wiley
AN - OPUS4-59427
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wedel, F.
A1 - Pitters, S.
A1 - Herrmann, Ralf
A1 - Schneider, Ronald
A1 - Hille, Falk
A1 - Hindersmann, I.
T1 - Guideline for the strategic application of monitoring of road bridges in Germany
N2 - Engineering structures are an important part of our transport infrastructure. Their failure is associated with high safety risks and economic damage. Ensuring the availability of these constructions and guaranteeing their operational safety are thus important tasks. Currently, maintenance of engineering structures is a reactive process and therefore not yet a predictive process. Every 3 to 6 years, the structures are visually inspected, all damages are documented and a condition grade is assigned to the structure based on the detected damages. Continuous data-providing methods such as monitoring are used only very occasionally. With the help of monitoring, condition data about the structures are continuously collected, which can be used for a better assessment of the structures. On the one hand, this would increase safety of engineering structures, and on the other hand, it makes the shift towards predictive maintenance management based on real-time data and predictions, where the onset of damage is detected before it occurs, possible in the first place. Monitoring plays therefore an important role in the management of the infrastructure. It is a crucial a step towards the digitalisation of our infrastructure and existing processes. Although there are many use cases for monitoring that have already been successfully implemented, monitoring is not yet widely used by German road authorities due to several challenges that were also identified within the scope of the project. Therefore, a guide has been developed in which the current obstacles related to monitoring are identified and possibilities for integrating monitoring into existing processes are offered. To ensure optimal alignment with the needs of road authorities, both an online survey and a workshop have been conducted. The results are summarised in a brochure that is made available to authorities to improve the use of monitoring in Germany. This paper presents the guideline and the brochure.
T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2024)
CY - Potsdam, Germany
DA - 10.06.2024
KW - Verkehrsinfrastrukturen
KW - Engineering Structures
KW - Bridges
KW - Structural Health Monitoring
KW - Guideline
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612821
UR - https://www.ndt.net/search/docs.php3?id=29582
DO - https://doi.org/10.58286/29582
SN - 1435-4934
VL - 29
IS - 7
SP - 1
EP - 8
PB - NDT.net GmbH & Co. KG
CY - Mayen
AN - OPUS4-61282
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Pirskawetz, Stephan
A1 - Thiele, Marc
A1 - Löhr, Manuel
A1 - Loewe, Anna
A1 - Degener, Sebastian
A1 - Herrmann, Ralf
T1 - Acoustic emission for monitoring of fatigue damage in concrete elements of wind turbine towers
N2 - Wind energy has become an important player in the energy transition in Germany. Towers of onshore wind turbines are often designed as hybrid structures: the lower part is made of prestressed concrete whereas the upper part is made of steel tubes. The tall structures are permanently subjected to cyclic loads. A research project of BAM as part of the joint project WinConFat - Structure focusses on the evelopment of techniques to monitor fatigue damage evolution in the concrete part. Results of a previous project show that a combination of ultrasonic and acoustic emission testing can give an indication for critical conditions near the end of the fatigue life of the concrete. In the ongoing project acoustic emission sensors have been installed at the base and at the transition piece between concrete and steel of a hybrid wind turbine tower. Beside of acoustic emission measurement the sensor spacing allows for measuring the concrete ultrasonic velocity along the circumference in both levels. Additional measurements like strain, temperature, inclination, or acceleration allow for comparison of environmental loads and change of acoustic properties of the concrete. The paper focusses on first acoustic measurements recorded since December 2023 in comparison to operating data of the wind turbine.
T2 - EWGAE2024: 36th Conference of the European Working Group on Acoustic Emission
CY - Potsdam, Germany
DA - 18.09.2024
KW - Concrete fatigue monitoring
KW - Acoustic emission
KW - Ultrasound
KW - Hybrid wind turbine tower
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612197
DO - https://doi.org/10.58286/30234
SN - 1435-4934
VL - 29
IS - 10
SP - 1
EP - 9
AN - OPUS4-61219
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Munsch, Sarah Mandy
A1 - Klewe, Tim
A1 - Schumacher, K.
A1 - Telong, Melissa
A1 - Grobla, Lili
A1 - Völker, C.
A1 - Yared, K.
A1 - Kruschwitz, Sabine
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Anwendung von KI für die Materialoptimierung im Bauwesen
N2 - Diese Arbeit untersucht den Einsatz von Künstlicher Intelligenz (KI) in der Materialentwicklung für Beton, mit einem Fokus auf Karbonatisierungswiderstand, CO₂-Reduktion und Kostenoptimierung. Das KI-Tool SLAMD, das auf inverses Materialdesign setzt, konnte in Studien die Entwicklungszeit für Betonmischungen um bis zu 80 % verkürzen. Durch die Integration zusätzlicher 1H-Kernspinresonanz-Daten wurde der Prozess um weitere 40 % beschleunigt. Insgesamt zeigt sich, dass der Einsatz von KI die Effizienz und Nachhaltigkeit in der Materialentwicklung signifikant steigern kann.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Künstliche Intelligenz (KI)
KW - Materialoptimierung
KW - Bauwesen
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612949
SN - 978-3-9818564-7-7
SP - 192
EP - 200
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61294
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Unger, Jörg F.
A1 - Tamsen, Erik
A1 - Agrawal, A.
A1 - Koutsourelakis, P.-S.
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Von Messdaten zum optimierten Bauteil durch Kombination von Material- und Strukturdesign
N2 - Die Entwicklung eines optimierten Designs für Bauwerke erfordert die Berücksichtigung sowohl des Materials als auch des Strukturdesigns. Ziel des Beitrages ist die Vorstellung eines Designprinzips basierend auf automatisierten Workflows, das am Beispiel eines Biegebalkendesign zur Reduzierung des Treibhauspotenzials vorgestellt wird. Eine ganzheitliche Optimierung berücksichtigt Material- und Strukturdesign. Es werden physikalische Modelle mit Ansätzen aus dem maschinellen Lernen kombiniert, die mit experimentellen Daten kalibriert bzw. trainiert werden. Eine besondere Bedeutung hat dabei die Berücksichtigung von Unsicherheiten.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Materialdesign
KW - Strukturdesign
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613003
SN - 978-3-9818564-7-7
SP - 209
EP - 217
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61300
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Telong, Melissa
A1 - Zoriyatkha, Aida
A1 - Pirskawetz, Stephan
A1 - Meng, Birgit
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Beton-Datenmanagement anhand von wissensbasierten Datenstrukturen unter Nutzung von Ontologien und Wissensgraphen
N2 - Im Rahmen der Entwicklung von Betonrezepturen, bei der Betonherstellung und während der Nutzungsphase im Bauwerk, wird eine Vielzahl von Materialdaten generiert. LeBeDigital (Lebenszyklus von Beton - Ontologie- Entwicklung für die Prozesskette der Betonherstellung) ist ein Verbundprojekt innerhalb der Initiative Plattform Material Digital. Das Projekt zielt darauf ab, eine Struktur für Betonmaterialdatenbanken zu entwickeln, die dem FAIR-Prinzip folgt und sowohl praxisnah als auch flexibel genug ist, um zukünftige Entwicklungen in der Betonforschung und -produktion zu unterstützen. Ontologien stellen ein geeignetes Werkzeug zur Generierung von Wissensgraphen dar, um Workflows zur automatisierten Datenerfassung und zur semantischen Datenabfrage zu gestalten. Daher ist die Erarbeitung betonspezifischer Ontologien zentraler Bestandteil des Verbundprojektes, das dazu beitragen will, die Vorrausetzungen für eine Teilhabe der Betonbranche am digitalen Wandel im Bereich der Materialforschung zu sichern.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Beton-Datenmanagement
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612984
SN - 978-3-9818564-7-7
SP - 201
EP - 208
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61298
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Herrmann, Ralf
A1 - Hille, Falk
A1 - Pitters, S.
A1 - Ramasetti, Eshwar Kumar
A1 - Schneider, Ronald
A1 - Wedel, F.
A1 - Hindersmann, I.
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Föderiertes Datenmanagement von Monitoringdaten aus Structural Health Monitoring Anwendungen und daraus gewonnenen Trainingsdaten bei Spannbetonbrücken
N2 - Beim Structural Health Monitoring entstehen eine Vielzahl von Daten, Metadaten und Modellen mit hohem Wert für die Beurteilung des Bauwerkszustands und der Prognose von Veränderungen. Kontinuierlich anwachsende Datenbestände müssen nachhaltig geteilt, genutzt und über die Bauwerkslebensdauer archiviert werden. Dabei stellen die Vielfalt der Messaufgaben, die Heterogenität der Daten, die dezentrale Erfassung und z. T. der Umfang eine Herausforderung für die beteiligten Akteure dar. Für den Datentransfer der Monitoringdaten zwischen der Straßenbauverwaltung und den Monitoringausführenden wird ein flexibles Abstimmungsverfahren vorgeschlagen und ein Lösungskonzept für ein föderiertes Datenmanagement skizziert. Eine weitere Herausforderung stellt die bauwerksübergreifende Zusammenstellung von Trainingsdaten für konkrete KI-Anwendungen dar.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Structural Health Monitoring
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612902
SN - 978-3-9818564-7-7
SP - 178
EP - 185
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61290
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Hille, Falk
A1 - Herrmann, Ralf
A1 - Pitters, S.
A1 - Hindersmann, I.
A1 - Schneider, Ronald
A1 - Wedel, F.
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Leitfaden für den strategischen Einsatz von Monitoring an Straßenbrücken
N2 - Für die Anwendung von Structural Health Monitoring (SHM) im Rahmen des Managements von Straßenbrü-cken wurde zur Unterstützung von Straßenbauverwaltungen, Ingenieurbüros, Bauunternehmen und weiteren Akteuren die Erstellung eines Leitfadens initiiert. Dieser Leitfaden stellt typische Anwendungsfälle für Monito-ring vor und schlägt für diese bewährte Herangehensweisen vor. Darüber hinaus bietet der Leitfaden Empfeh-lungen für Ausschreibung und Vergabe von Monitoringleistungen, eine Anleitung zur Bewertung des wirt-schaftlichen Nutzens von SHM, Hinweise zur optimal einsetzbaren Messtechnik sowie einen Ansatz für das Datenmanagement zur Integration der Monitoringdaten in das Brückenmanagement.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Leitfaden
KW - Monitoring
KW - Straßenbrücke
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612931
SN - 978-3-9818564-7-7
SP - 186
EP - 191
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61293
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rosenbusch, Sjard Mathis
A1 - Balzani, D.
A1 - Unger, Jörg F.
T1 - Regularization of softening plasticity models for explicit dynamics using a gradient-enhanced modified Johnson–Holmquist model
N2 - The behavior of concrete under high strain rates is often described by plasticity models with softening, which is modeled by a reduction of the yield surface as a function of the local equivalent plastic strain. Many of these models are local and therefore produce mesh-dependent results. In this contribution, the gradient-enhancement of such models is investigated to mitigate the mesh-dependency.
First, the mesh-dependency of these local formulations based on the analysis with a modified JH2 model as a representative for these constitutive formulations is demonstrated using a one-dimensional benchmark example. In the benchmark, the width of the damaged zone decreases upon mesh-refinement and the dissipated plastic energy tends to zero. It is further shown that a significantly small safety factor for the critical time step is needed in order to achieve accurate results for the benchmark example.
The first investigated gradient-enhancement approach replaces the equivalent local plastic strain with its nonlocal counterpart. The enhancement is based on the inclusion of inertia and damping to the additional Helmholtz equation which enables the use of the central difference method as an explicit solver. This method successfully distributes the damage over several elements, however, the local equivalent plastic strain still localizes into one cell. The inclusion of hardening with respect to the local equivalent plastic strain inhibits the localization and the dissipated plastic energy converges with mesh-refinement.
This is further confirmed in a two-dimensional wedge-splitting experiment and a four-point bending test where the damage pattern produced by the local model is mesh-dependent as well and the dissipated plastic energy tends to zero with mesh-refinement. The proposed nonlocal model with hardening results in a consistent damage pattern and the dissipated plastic energy converges. Furthermore, the nonlocal model with hardening is less sensitive to time step refinement, such that computational efficiency can be improved compared to the local model. The numerical experiments are implemented using the free open source tool FEniCSx and have been made available on Zenodo.
KW - Gradient plasticity
KW - Explicit dynamics
KW - JH2 model
KW - Concrete modeling
KW - FEniCS
KW - Mesh convergence
KW - Time step convergence
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-630453
DO - https://doi.org/10.1016/j.ijimpeng.2024.105209
SN - 1879-3509
VL - 198
SP - 1
EP - 18
PB - Elsevier Ltd.
CY - Schweiz
AN - OPUS4-63045
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sittner, Jonathan
A1 - Götze, Jens
A1 - Müller, Axel
A1 - Renno, Axel D.
A1 - Ziegenrücker, René
A1 - Pan, Yuanming
T1 - Trace element analysis and luminescence behavior of quartz in pegmatites of the Tørdal Region, Norway
N2 - This publication presents a study on the mineral chemistry and luminescence properties of quartz samples from pegmatites of the Tørdal region in Norway. A total of 12 samples were analyzed using Secondary Ion Mass Spectrometry (SIMS), Electron Paramagnetic Resonance Spectroscopy (EPR), and Cathodoluminescence (CL) to gain insights into their trace element concentration and distribution as well as their luminescence behavior. The samples are characterized by different Cl emissions at 450 nm, 500 nm 650 nm and an additional shoulder at 390 nm, which is only partially visible due to the absorption of the glass optics. Of these luminescence bands, the 500 nm band is the most dominant in most samples and it is characterized by an initial blue-green luminescence, which is not stable under electron irradiation. Moreover, it is characterized by a heterogeneous distribution within the samples. This luminescence can be mostly assigned to [AlO4/M+]0 defects, with charge compensation mostly achieved by Li+. Analyses by EPR spectroscopy prove the dominance of structurally bound Al, Li, and Ti ions in the investigated samples. Further analyses using SIMS mapping demonstrate that Na and K are mainly bound to micro fractures or inclusions, suggesting a limited role in the compensation of the luminescence centers. Additionally, the SIMS mappings show that some samples contain Al-rich clusters of 10 to 20 µm in diameter, whereas other trace elements are characterized by a homogeneous distribution. These clusters correspond to bright luminescence areas in size and shape and could potentially indicate H+ compensated [AlO4/M+]0 defects.
KW - Quartz
KW - Trace elements
KW - SIMS
KW - Cathodoluminescence
KW - EPR
KW - Tørdal
KW - Pegmatite
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612529
DO - https://doi.org/10.1016/j.chemgeo.2024.122427
VL - 670
SP - 1
EP - 15
PB - Elsevier BV
AN - OPUS4-61252
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Hüsken, Götz
A1 - Jeyifous, Olubunmi Anthony
A1 - Schönsee, Eric
A1 - Strangfeld, Christoph
T1 - An assessment of the repeatability of 3D printed concrete structures
N2 - Additive manufacturing of concrete structures, also known as 3D concrete printing, is a technology that received a lot of attention over the past decade due to its financial an ecological advantage as sustainable construction technology. Although several techniques and approaches demonstrate these advantages, quality control during printing is highly challenging and rarely applied and harmonized standards are not existing. Due to the continuous mixing process used in 3D concrete printing, it is impossible to exclude variations in the dry mixture or water content, and a single test sample is insufficient to be representative for the whole structure. A defect in one layer during the printing can affect the entire integrity of the whole structure. This study shows the results of an arch designed as framework structure that was printed multiple times under the same boundary conditions using an extrusion-based 3D concrete printer. Each arch was tested for its mechanical strength and load bearing behavior. The results of the mechanical testing of the printed arches are compared with material data obtained by classical tests and discussed regarding their statistical significance.
T2 - Digital Concrete 2024
CY - Munich, Germany
DA - 04.09.2024
KW - 3D concrete printing
KW - Repeatability
KW - Monitoring
KW - Process control
KW - Quality control
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611012
DO - https://doi.org/10.24355/dbbs.084-202408150641-0
SP - 1
EP - 9
PB - TU Braunschweig
AN - OPUS4-61101
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mugani, R.
A1 - El Khalloufi, F.
A1 - Kasada, M.
A1 - Redouane, E. M.
A1 - Haida, M.
A1 - Aba, R. P.
A1 - Essadki, Y.
A1 - Zerrifi, S. E. A.
A1 - Herter, Sven-Oliver
A1 - Hejjaj, A.
A1 - Aziz, F.
A1 - Ouazzani, N.
A1 - Azevedo, J.
A1 - Campos, A.
A1 - Putschew, A.
A1 - Grossart, H.-P.
A1 - Mandi, L.
A1 - Vasconcelos, V.
A1 - Oudra, B.
T1 - Monitoring of toxic cyanobacterial blooms in Lalla Takerkoust reservoir by satellite imagery and microcystin transfer to surrounding farms
N2 - Cyanobacterial harmful algal blooms (CyanoHABs) threaten public health and freshwater ecosystems worldwide. In this study, our main goal was to explore the dynamics of cyanobacterial blooms and how microcystins (MCs) move from the Lalla Takerkoust reservoir to the nearby farms. We used Landsat imagery, molecular analysis, collecting and analyzing physicochemical data, and assessing toxins using HPLC. Our investigation identified two cyanobacterial species responsible for the blooms: Microcystis sp. and Synechococcus sp. Our Microcystis strain produced three MC variants (MC-RR, MC-YR, and MC-LR), with MC-RR exhibiting the highest concentrations in dissolved and intracellular toxins. In contrast, our Synechococcus strain did not produce any detectable toxins. To validate our Normalized Difference Vegetation Index (NDVI) results, we utilized limnological data, including algal cell counts, and quantified MCs in freeze-dried Microcystis bloom samples collected from the reservoir. Our study revealed patterns and trends in cyanobacterial proliferation in the reservoir over 30 years and presented a historical map of the area of cyanobacterial infestation using the NDVI method. The study found that MC-LR accumulates near the water surface due to the buoyancy of Microcystis. The maximum concentration of MC-LR in the reservoir water was 160 μg/L. In contrast, 4 km downstream of the reservoir, the concentration decreased by a factor of 5.39 to 29.63 μg/L, indicating a decrease in MC-LR concentration with increasing distance from the bloom source. Similarly, the MC-YR concentration decreased by a factor of 2.98 for the same distance. Interestingly, the MC distribution varied with depth, with MC-LR dominating at the water surface and MC-YR at the reservoir outlet at a water depth of 10 m. Our findings highlight the impact of nutrient concentrations, environmental factors, and transfer processes on bloom dynamics and MC distribution. We emphasize the need for effective management strategies to minimize toxin transfer and ensure public health and safety.
KW - Cyanotoxin
KW - HPLC-MS/MS
KW - Surface water
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623672
DO - https://doi.org/10.1016/j.hal.2024.102631
SN - 1568-9883
VL - 135
SP - 1
EP - 14
PB - Elsevier
CY - Amsterdam
AN - OPUS4-62367
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schneider, Ronald
A1 - Simon, Patrick
A1 - Hille, Falk
A1 - Herrmann, Ralf
A1 - Baeßler, Matthias
T1 - Vibration-based system identification of a large steel box girder bridge
N2 - The Bundesanstalt für Materialforschung und -prüfung (BAM) collaborates with TNO to develop a software framework for automated calibration of structural models based on monitoring data. The ultimate goal is to include such models in the asset management process of engineering structures. As a basis for developing the framework, a multi-span road bridge consisting of ten simply supported steel box girders was selected as a test case. Our group measured output-only vibration data from one box girder under ambient conditions. From the data, we determined eigenfrequencies and mode shapes. In parallel, we developed a preliminary structural model of the box girder for the purpose of predicting its modal properties. In this contribution, we provide an overview of the measurement campaign, the operational modal analysis, the structural modeling and qualitatively compare the identified with the predicted modes. As an outlook, we discuss the further steps in the calibration process and future applications of the calibrated model.
T2 - XII International Conference on Structural Dynamics (EURODYN 2023)
CY - Delft, The Netherlands
DA - 02.07.2023
KW - Verkehrsinfrastukturen
KW - SHM
KW - Model updating
KW - System identification
KW - Operational modal analysis
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605041
DO - https://doi.org/10.1088/1742-6596/2647/18/182039
SN - 1742-6596
VL - 2647
IS - 18
SP - 1
EP - 9
PB - IOP Publishing
CY - Bristol
AN - OPUS4-60504
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schardt, Annika
A1 - Schmitt, Johannes
A1 - Engelhard, Carsten
T1 - Single particle inductively coupled plasma mass spectrometry with nanosecond time resolution
N2 - In this proof-of-principle study, we present our contribution to single particle inductively coupled plasma mass spectrometry (spICP-MS) developments with a novel in-house built data acquisition system with nanosecond time resolution (nanoDAQ) and a matching data processing approach. The new system can continuously sample the secondary electron multiplier (SEM) detector signal and enables the detection of gold nanoparticles (AuNP) as small as 7.5 nm with the commercial single quadrupole ICP-MS instrument used in this study. Recording of the SEM signal by the nanoDAQ is performed with a dwell time of approximately 4 ns. A tailored method was developed to process this type of transient data, which is based on determining the temporal distance between detector events that is denoted as event gap (EG). We found that the inverse logarithm of EG is proportional to the particle size and that the number of detector events corresponding to a particle signal distribution can be used to calibrate and determine the particle number concentration (PNC) of a nanoparticle dispersion. Due to the high data acquisition frequency, a statistically significant number of data points can be obtained in 60 s or less and the main time limitation for analyses is merely the sample uptake time and rinsing step between analyte solutions. At this stage, the data processing method provides average information on complete data sets only and will be adapted to enable particle-by-particle analysis with future hardware/software revision.
KW - ICP-MS
KW - Nanoparticles
KW - Nanosecond time resolution
KW - Single particle detection
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612706
DO - https://doi.org/10.1039/d3ja00373f
SN - 1364-5544
SN - 0267-9477
VL - 39
IS - 2
SP - 389
EP - 400
PB - Royal Society of Chemistry (RSC)
CY - Cambridge
AN - OPUS4-61270
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Simon, Patrick
A1 - Schneider, Ronald
A1 - Baeßler, Matthias
A1 - Morgenthal, Guido
ED - Cha, Young-Jin
T1 - A Bayesian Probabilistic Framework for Building Models for Structural Health Monitoring of Structures Subject to Environmental Variability
N2 - Managing aging engineering structures requires damage identification, capacity reassessment, and prediction of remaining service life. Data from structural health monitoring (SHM) systems can be utilized to detect and characterize potential damage. However, environmental and operational variations impair the identification of damages from SHM data. Motivated by this, we introduce a Bayesian probabilistic framework for building models and identifying damage in monitored structures subject to environmental variability. The novelty of our work lies (a) in explicitly considering the effect of environmental influences and potential structural damages in the modeling to enable more accurate damage identification and (b) in proposing a methodological workflow for model‐based structural health monitoring that leverages model class selection for model building and damage identification. The framework is applied to a progressively damaged reinforced concrete beam subject to temperature variations in a climate chamber. Based on deflections and inclinations measured during diagnostic load tests of the undamaged structure, the most appropriate modeling approach for describing the temperature‐dependent behavior of the undamaged beam is identified. In the damaged state, damage is characterized based on the identified model parameters. The location and extent of the identified damage are consistent with the cracks observed in the laboratory. A numerical study with synthetic data is used to validate the parameter identification. The known true parameters lie within the 90% highest density intervals of the posterior distributions of the model parameters, suggesting that this approach is reliable for parameter identification. Our results indicate that the proposed framework can answer the question of damage identification under environmental variations. These findings show a way forward in integrating SHM data into the management of infrastructures.
KW - Verkehrsinfrastukturen
KW - SHM
KW - Model Updating
KW - Environmental and Operational Variability
KW - Damage Identification
KW - Model Building
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605027
DO - https://doi.org/10.1155/2024/4204316
SN - 1545-2255
VL - 2024
IS - 1
SP - 1
EP - 23
PB - Wiley
AN - OPUS4-60502
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Herrmann, Ralf
A1 - Ramasetti, Eshwar Kumar
A1 - Degener, Sebastian
A1 - Hille, Falk
A1 - Baeßler, Matthias
T1 - A living lab for Structural Health Monitoring at the Nibelungen Bridge Worms for Transfer Learning of Structural Dynamics
N2 - The Nibelungen Bridge in Worms, Germany has been selected as a national demonstration structure for advanced non-destructive testing (NDT) and structural health monitoring concepts to extend the lifetime of civil structures and to optimize O&M actions. Parts of the research that involves this bridge as a demonstrator belong to the focus area program SPP100+. In this program, the bridges SHM System has been extended and combined with an additional setup of vibration sensors. The used digital smart sensor with pre-processing functions, the arrangement of the sensors at the structure and additional edge computing capability allows the investigation of transfer learning and other methods directly into the real structure. The living lab with seven triaxial accelerometers can be reconfigured in real-time and adjusted to the needs of AI models for classification. The comparison with the existing conventional SHM sensors has been made possible by hardware synchronization to the existing SHM System and collocating sensors at similar positions, so that a hardware exchange can be an investigated use-case for the transfer learning. During idle times, the system collects vibration data like a conventional SHM system.
T2 - 10th European Workshop on Structural Health Monitoring (EWSHM 2024)
CY - Potsdam
DA - 10.06.2024
KW - Nibelungen Bridge
KW - Living Lab
KW - Transfer Learning
KW - Transfer Structures
KW - Modal Analysis
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612810
UR - https://www.ndt.net/search/docs.php3?id=29853
DO - https://doi.org/10.58286/29853
SN - 1435-4934
VL - 29
IS - 7
SP - 1
EP - 8
PB - NDT.net GmbH & Co. KG
CY - Mayen
AN - OPUS4-61281
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Simon, Patrick
A1 - Baeßler, Matthias
ED - Rogge, Andreas
ED - Meng, Birgit
T1 - Temperatureinfluss auf Strukturmonitoring – Aktuelle Versuche
N2 - Strukturmonitoring kann wertvolle Daten für die Zustandsbewertung und Schadensdetektion von Infrastrukturbauwerken liefern. Umgebungsbedingungen wie die Temperatur beeinflussen die Bauwerke und somit die Messdaten jedoch erheblich. Um Methoden für den Umgang mit Temperatureinflüssen zu entwickeln, wurden an der BAM Versuche an Stahlbeton- und Asphaltbalken unter kontrollierten Temperaturen von -40 °C bis 60 °C und definierten Schädigungen durchgeführt. Die Daten ermöglichen die Erforschung und Validierung neuer, auch unter Temperatureinfluss zuverlässiger Methoden des Strukturmonitorings.
T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building
CY - Berlin, Germany
DA - 16.10.2024
KW - Strukturmonitoring
KW - Temperatureinfluss
KW - Infrastrukturbauwerke
KW - Stahlbeton- und Asphaltbalken
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-613289
SN - 978-3-9818564-7-7
SP - 294
EP - 302
PB - Bundesanstalt für Materialforschung und -prüfung (BAM)
CY - Berlin
AN - OPUS4-61328
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ramasetti, Eshwar Kumar
A1 - Herrmann, Ralf
A1 - Degener, Sebastian
A1 - Baeßler, Matthias
T1 - Development of generic AI models to predict the movement of vehicles on bridges
N2 - For civil, mechanical, and aerospace structures to extend operation times and to remain in service, structural health monitoring (SHM) is vital. SHM is a method to examining and monitoring the dynamic behavior of essential constructions. Because of its versatility in detecting unfavorable structural changes and enhancing structural dependability and life cycle management, it has been extensively used in many engineering domains, especially in civil bridges. Due to the recent technical developments in sensors, high-speed internet, and cloud computing, data-driven approaches to structural health monitoring are gaining appeal. Since artificial intelligence (AI), especially in SHM, was introduced into civil engineering, these modern and promising methods have attracted significant research attention. In this work, a large dataset of acceleration time series using digital sensors was collected by installing a structural health monitoring (SHM) system on Nibelungen Bridge located in Worms, Germany. In this paper, a deep learning model is developed for accurate classification of different types of vehicle movement on the bridge from the data obtained from accelerometers. The neural network is trained with key features extracted from the acceleration dataset and classification accuracy of 98 % was achieved.
KW - Structural Health Monitoring
KW - Artifical Intelligence
KW - Machine Learning
KW - Nibelungen Bridge
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-620289
DO - https://doi.org/10.1016/j.prostr.2024.09.307
VL - 64
SP - 557
EP - 564
PB - Elsevier B.V.
AN - OPUS4-62028
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Asna Ashari, Parsa
A1 - Oh, Hyochan
A1 - Koch, Claudia
T1 - Pathways to the hydrogen economy: A multidimensional analysis of the technological innovation systems of Germany and South Korea
N2 - The global trend towards decarbonization and the demand for energy security have put hydrogen energy into the spotlight of industry, politics, and societies. Numerous governments worldwide are adopting policies and strategies to facilitate the transition towards hydrogen-based economies. To assess the determinants of such transition, this study presents a comparative analysis of the technological innovation systems (TISs) for hydrogen technologies in Germany and South Korea, both recognized as global frontrunners in advancing and implementing hydrogen-based solutions. By providing a multidimensional assessment of pathways to the hydrogen economy, our analysis introduces two novel and crucial elements to the TIS analysis: (i) We integrate the concept of ‘quality infrastructure’ given the relevance of safety and quality assurance for technology adoption and social acceptance, and (ii) we emphasize the social perspective within the hydrogen TIS. To this end, we conducted 24 semi-structured expert interviews, applying qualitative open coding to analyze the data. Our results indicate that the hydrogen TISs in both countries have undergone significant developments across various dimensions. However, several barriers still hinder the further realization of a hydrogen economy. Based on our findings, we propose policy implications that can facilitate informed policy decisions for a successful hydrogen transition.
KW - Hydrogen economy
KW - Technological innovation system
KW - Quality infrastructure
KW - Multidimensional technology adoption
KW - Social acceptance
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593312
DO - https://doi.org/10.1016/j.ijhydene.2023.08.286
IS - Volume 49, Part D
SP - 405
EP - 421
PB - Elsevier
AN - OPUS4-59331
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Swaminathan, Srinivasan
A1 - Kumar, S.
A1 - Kranzmann, Axel
A1 - Hesse, Rene
A1 - Goldbeck, Hennig
A1 - Fantin, Andrea
T1 - Corrosion characteristics of 316L stainless steel in oxide-rich molten solar salt at 600◦C
N2 - An attempt has been made in this work, to observe the influence on alloy aging by the sodium oxide (Na2O) in solar salt (60 wt% NaNO3 + 40 wt% KNO3). The accelerated aging was established by adding Na2O (0.005, 0.07, 0.135 and 0.2 wt%) to the solar salt and their effect on corrosion of 316L stainless steel (SS) at 600 ◦C in that oxide-rich solar salts for 168 h in synthetic air was investigated. Corrosion is significantly more in oxide-rich solar salt compared to pure solar salt. Strikingly, the oxide scale-base metal interface is wavy in solar salt containing 0.005 % Na2O clearly shows the oxide addition to salt melt influences Cr-rich inner oxide layer formation and its selective dissolution at early stage that leads to non-uniform corrosion. Interestingly, with increase of Na2O to 0.07 %, steel corrosion proceeded uniformly by accelerated disintegration of Cr-rich inner layer and subsequent dissolution. Severe scale spallation and weight loss in nitrate melt containing 0.2 % Na2O fostering more rapid corrosion, alarming that substantial tolerance of oxide content in solar salt is ≥ 0.135 % for an acceptable corrosion of 316L SS. Despite preferential dissolution of Cr and scale degradation/spallation with increased oxide content in solar salt, the corrosion layer in all cases comprised of sodium ferrite, and Cr-rich Cr-Fe mixed oxides with the Ni enrichment at the scale-metal interface. Competing processes between oxide scale growth, degradation and dissolution or even spallation has been discussed with an emphasis of Na2O addition to solar salt.
KW - Molten salt corrosion
KW - Solar salt
KW - Thermal energy storage
KW - Stainless steel
KW - Concentrating solar power
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610819
DO - https://doi.org/10.1016/j.solmat.2024.113176
VL - 278
SP - 1
EP - 13
PB - Elsevier B.V.
AN - OPUS4-61081
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kimiaei, E.
A1 - Farooq, M.
A1 - Szymoniak, Paulina
A1 - Ahmadi, Shayan
A1 - Babaeipour, S.
A1 - Schönhals, Andreas
A1 - Österberg, M.
T1 - The role of lignin as interfacial compatibilizer in designing lignocellulosic-polyester composite films
N2 - Advancing nanocomposites requires a deep understanding and careful design of nanoscale interfaces, as interfacial interactions and adhesion significantly influence the physical and mechanical properties of these materials. This study demonstrates the effectiveness of lignin nanoparticles (LNPs) as interfacial compatibilizer between hydrophilic cellulose nanofibrils (CNF) and a hydrophobic polyester, polycaprolactone (PCL). In this context, we conducted a detailed analysis of surface-to-bulk interactions in both wet and dry conditions using advanced techniques such as quartz crystal microbalance with dissipation (QCM-D), atomic force microscopy (AFM), water contact angle (WCA) measurements, broadband dielectric spectroscopy (BDS), and inverse gas chromatography (IGC).
QCM-D was employed to quantify the adsorption behavior of LNPs on CNF and PCL surfaces, demonstrating LNPs’ capability to interact with both hydrophilic and hydrophobic phases, thereby enhancing composite material properties. LNPs showed extensive adsorption on a CNF model film (1186 ± 178 ng.cm−2) and a lower but still significant adsorption on a PCL model film (270 ± 64 ng.cm−2). In contrast, CNF adsorption on a PCL model film was the lowest, with a sensed mass of only 136 ± 35 ng.cm−2. These findings were further supported by comparing the morphology and wettability of the films before and after adsorption, using AFM and WCA analyses. Then, to gain insights into the molecular-level interactions and molecular mobility within the composite in dry state, BDS was employed. The BDS results showed that LNPs improved the dispersion of PCL within the CNF network. To further investigate the impact of LNPs on the composites’ interfacial properties, IGC was employed. This analysis showed that the composite films containing LNPs exhibited lower surface energy compared to those composed of only CNF and PCL. The presence of LNPs likely reduced the availability of surface hydroxyl groups, thus modifying the physicochemical properties of the interface. These changes were particularly evident in the heterogeneity of the surface energy profile, indicating that LNPs significantly altered the interfacial characteristics of the composite materials.
Overall, these findings emphasize the necessity to control the interfaces between components for next-generation nanocomposite materials across diverse applications.
KW - Lignin
KW - Nanocomposites
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615098
DO - https://doi.org/10.1016/j.jcis.2024.10.083
SN - 0021-9797
VL - 679
SP - 263
EP - 275
PB - Elsevier Inc.
AN - OPUS4-61509
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lauhoff, Christian
A1 - Degener, Sebastian
A1 - Bolender, Artjom
A1 - Liehr, Alexander
A1 - Hübner, Leoni
A1 - Frenck, Johanna-Maria
A1 - Molotnikov, Andrey
A1 - Niendorf, Thomas
T1 - In Situ Synchrotron Diffraction Assessment of Reversibility of the Martensitic Transformation in Single-Crystalline Co–Ni–Ga Shape Memory Alloy Under Torsion
N2 - AbstractHeusler-type Co–Ni–Ga shape memory alloys attracted significant attention due to their excellent functional properties in single-crystalline state under both compressive and tensile loading. The present study investigates the superelastic deformation behavior under torsion. Using a newly installed torsion testing setup, in situ synchrotron diffraction was carried out on single-crystalline material in order to investigate the martensitic phase transformation. Incremental deformation experiments reveal a fully reversible martensitic transformation under torsional loading at room temperature, leading to excellent strain recovery after deformation to 6.5% shear strain. Furthermore, relevant aspects towards the analysis of powder diffraction data obtained for single-crystalline material in transmission mode under torsional loading are presented and critically discussed.
KW - Shape memory alloy
KW - Pseudoelasticity
KW - Martensitic transformation
KW - Synchrotron diffraction
KW - In situ testing
KW - Torsion
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621872
DO - https://doi.org/10.1007/s40830-024-00496-8
VL - 10
SP - 326
EP - 333
PB - Springer Science and Business Media LLC
AN - OPUS4-62187
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zhang, Runze
A1 - Sur, Debashish
A1 - Li, Kangming
A1 - Witt, Julia
A1 - Black, Robert
A1 - Whittingham, Alexander
A1 - Scully, John R.
A1 - Hattrick-Simpers, Jason
T1 - Bayesian assessment of commonly used equivalent circuit models for corrosion analysis in electrochemical impedance spectroscopy
N2 - Electrochemical Impedance Spectroscopy (EIS) is a crucial technique for assessing corrosion of metallic materials. The analysis of EIS hinges on the selection of an appropriate equivalent circuit model (ECM) that accurately characterizes the system under study. In this work, we systematically examined the applicability of three commonly used ECMs across several typical material degradation scenarios. By applying Bayesian Inference to simulated corrosion EIS data, we assessed the suitability of these ECMs under different corrosion conditions and identified regions where the EIS data lacks sufficient information to statistically substantiate the ECM structure. Additionally, we posit that the traditional approach to EIS analysis, which often requires measurements to very low frequencies, might not be always necessary to correctly model the appropriate ECM. Our study assesses the impact of omitting data from low to medium-frequency ranges on inference results and reveals that a significant portion of low-frequency measurements can be excluded without substantially compromising the accuracy of extracting system parameters. Further, we propose simple checks to the posterior distributions of the ECM components and posterior predictions, which can be used to quantitatively evaluate the suitability of a particular ECM and the minimum frequency required to be measured. This framework points to a pathway for expediting EIS acquisition by intelligently reducing low-frequency data collection and permitting on-the-fly EIS measurements.
KW - Electrochemical Impedance Spectroscopy (EIS)
KW - MAPz@BAM
KW - Bayesian Inference
KW - Corrosion
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-623392
DO - https://doi.org/10.1038/s41529-024-00537-8
VL - 8
SP - 120
PB - Springer Materials
AN - OPUS4-62339
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Brockmann, N.
A1 - Sicken, A.
A1 - Krüger, Jörg
T1 - Effects of laser cleaning on the condition of different silk model samples using varying wavelengths and pulse durations
N2 - The cleaning of aged silk fibers poses a common challenge in the conservation of textiles, since traditional cleaning techniques often yield unsatisfactory results or even harm objects. In this regard, cleaning objects with laser radiation is a promising addition to the range of available methods. Due to it being contactless, even brittle and touch-sensitive objects with disfiguring or harmful soiling could potentially be cleaned and therefore made accessible for research and presentation. Examples of treatment have sometimes shown spectacular results. Still there is some skepticism concerning the safety of this treatment for textile materials, which has been strengthened through previous 532 nm wavelength nanosecond laser cleaning studies on silk fibers. Taking these published results into account, the range of examined laser parameters has been extended in this study, from 532 nm nanosecond laser to 1064 nm nanosecond and even 800 nm femtosecond laser, reevaluating the effect of this treatment on the fibers. The physicochemical processes taking place on the silk fibers when cleaning with lasers are complex and still not fully understood. The aim of this project was therefore to bring more clarification about potential effects of those processes on the condition of silk samples treated with a set of different parameters for wavelength, pulse duration, energy density and number of pulses per spot. It also looks at the influence of the presence of soiling on the results. The analysis of potential effects was then carried out using statistical methods and advanced analytics. Scanning electron microscopy, Fourier-transform infrared spectroscopy and colorimetry technology provided the required insights to better assess the effects. Results show that laser cleaning of silk fibers, like most other conventional cleaning techniques, is not completely without risk, but knowing what the possible effects are helps making decisions on whether the benefits of the technique used justify these risks.
KW - Laser cleaning
KW - Cultural heritage
KW - Conservation
KW - Silk
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594601
DO - https://doi.org/10.1186/s40494-024-01152-1
SN - 2050-7445
VL - 12
IS - 1
SP - 1
EP - 15
PB - Springer
AN - OPUS4-59460
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Was, G.S.
A1 - Bahn, C.-B.
A1 - Busby, J.
A1 - Cui, B.
A1 - Farkas, D.
A1 - Gussev, M.
A1 - Rigen He, M.
A1 - Hesterberg, J.
A1 - Jiao, Z.
A1 - Johnson, D.
A1 - Kuang, W.
A1 - McMurtrey, M.
A1 - Robertson, I.
A1 - Sinjlawi, A.
A1 - Song, M.
A1 - Stephenson, K.
A1 - Sun, K.
A1 - Swaminathan, Srinivasan
A1 - Wang, M.
A1 - West, E.
T1 - How irradiation promotes intergranular stress corrosion crack initiation
N2 - Irradiation assisted stress corrosion cracking (IASCC) is a form of intergranular stress corrosion cracking that occurs in irradiated austenitic alloys. It requires an irradiated microstructure along with high temperature water and stress. The process is ubiquitous in that it occurs in a wide range of austenitic alloys and water chemistries, but only when the alloy is irradiated. Despite evidence of this degradation mode that dates back to the 1960s, the mechanism by which it occurs has remained elusive. Here, using high resolution electron backscattering detection to analyze local stress-strain states, high resolution transmission electron microscopy to identify grain boundary phases at crack tips, and decoupling the roles of stress and grain boundary oxidation, we are able to unfold the complexities of the phenomenon to reveal the mechanism by which IASCC occurs. The significance of the findings impacts the mechanical integrity of core components of both current and advanced nuclear reactor designs worldwide.
KW - Irradiation
KW - Stress corrosion cracking
KW - Grain boundaries
KW - Oxidation
KW - Austenitic alloys
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595748
DO - https://doi.org/10.1016/j.pmatsci.2024.101255
SN - 0079-6425
VL - 143
SP - 1
EP - 15
PB - Elsevier
AN - OPUS4-59574
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Minenkov, Alexey
A1 - Hollweger, Sophia
A1 - Duchoslav, Jiri
A1 - Erdene-Ochir, Otgonbayar
A1 - Weise, Matthias
A1 - Ermilova, Elena
A1 - Hertwig, Andreas
A1 - Schiek, Manuela
T1 - Monitoring the Electrochemical Failure of Indium Tin Oxide Electrodes via Operando Ellipsometry Complemented by Electron Microscopy and Spectroscopy
N2 - Transparent conductive oxides such as indium tin oxide (ITO) are standards for thin film electrodes, providing a synergy of high optical transparency and electrical conductivity. In an electrolytic environment, the determination of an inert electrochemical potential window is crucial to maintain a stable material performance during device operation. We introduce operando ellipsometry, combining cyclic voltammetry (CV) with spectroscopic ellipsometry, as a versatile tool to monitor the evolution of both complete optical (i.e., complex refractive index) and electrical properties under wet electrochemical operational conditions. In particular, we trace the degradation of ITO electrodes caused by electrochemical reduction in a pH-neutral, water-based electrolyte environment during electrochemical cycling. With the onset of hydrogen evolution at negative bias voltages, indium and tin are irreversibly reduced to the metallic state, causing an advancing darkening, i.e., a gradual loss of transparency, with every CV cycle, while the conductivity is mostly conserved over multiple CV cycles. Post-operando analysis reveals the reductive (loss of oxygen) formation of metallic nanodroplets on the surface. The reductive disruption of the ITO electrode happens at the solid–liquid interface and proceeds gradually from the surface to the bottom of the layer, which is evidenced by cross-sectional transmission electron microscopy imaging and complemented by energy-dispersive X-ray spectroscopy mapping. As long as a continuous part of the ITO layer remains at the bottom, the conductivity is largely retained, allowing repeated CV cycling. We consider operando ellipsometry a sensitive and nondestructive tool to monitor early stage material and property changes, either by tracing failure points, controlling intentional processes, or for sensing purposes, making it suitable for various research fields involving solid–liquid interfaces and electrochemical activity.
KW - General Materials Science
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597625
DO - https://doi.org/10.1021/acsami.3c17923
SN - 1944-8252
VL - 16
IS - 7
SP - 9517
EP - 9531
PB - American Chemical Society (ACS)
AN - OPUS4-59762
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Knapic, D.
A1 - Mardare, A. I.
A1 - Voss, Heike
A1 - Bonse, Jörn
A1 - Hassel, A. W.
T1 - Corrosion study of picosecond-laser structured and anodized Ti6Al4V for bone screws
N2 - A corrosion study is performed on six variations of titanium grade 5 (Ti6Al4V) samples. Samples are prepared in different conditions by variation of preanodization, postanodization, and picosecond-laser (ps-laser) surface treatment, while polished and anodized samples serve as reference. Microcones and nanosized periodic surface features are successfully produced on Ti6Al4V samples. The morphology and topography of the structures are visualized by scanning electron microscopy and white light interference microscopy. Furthermore, the relative electrochemically active surface area (ECSA) is determined for the ps-laser-treated samples. It is determined that the preanodized and laser-treated sample has 3.5 times larger ECSA than a polished sample, and that the laser-treated sample has 4.1 times larger area. Moreover, Tafel analysis is performed to determine the corrosion properties of the samples. It is shown that the corrosion resistance improves for both laser-structured samples after the anodization. To further study the surface of the samples, electrochemical impedance spectroscopy measurements are conducted. The study indicates that the ps-laser-treated and anodized Ti6Al4V is suitable to be used for the fabrication of bone screws and plates due to its improved corrosion resistance as compared to nonanodized samples.
KW - Laser-induced periodic surface structures (LIPSS)
KW - Anodization
KW - Bone screws
KW - Implant material
KW - Titanium alloys
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597890
DO - https://doi.org/10.1002/pssa.202300609
SN - 1862-6319
VL - 221
SP - 1
EP - 8
PB - Wiley-VCH GmbH
CY - Weinheim
AN - OPUS4-59789
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Nawaz, Q.
A1 - Blaeß, Carsten
A1 - Mueller, Ralf
A1 - Boccaccini, A.R.
T1 - Processing and cytocompatibility of Cu-doped and undoped fluoride-containing bioactive glasses
N2 - Sintered or additive-manufactured bioactive glass (BG) scaffolds are highly interesting for bone replacement applications. However, crystallization often limits the high-temperature processability of bioactive glasses (BGs). Thus, the BG composition must combine high bioactivity and processability. In this study, three BGs with nominal molar (%) compositions 54.6SiO2-1.7P2O3-22.1CaO-6.0Na2O-7.9K2O-7.7MgO (13–93), 44.8SiO2-2.5P2O3-36.5CaO-6.6Na2O-6.6K2O-3.0CaF2 (F3) and 44.8SiO2-2.5P2O3-35.5CaO-6.6Na2O-6.6K2O-3.0CaF2-1.0CuO (F3–Cu) were investigated. The dissolution and ion release kinetics were investigated on milled glass powder and crystallized particles (500–600 μm). All glasses showed the precipitation of hydroxyapatite (HAp) crystals after 7 days of immersion in simulated body fluid. No significant differences in ion release from glass and crystalline samples were detected. The influence of surface roughness on cytocompatibility and growth of preosteoblast cells (MC3T3-E1) was investigated on sintered and polished BG pellets. Results showed that sintered BG pellets were cytocompatible, and cells were seen to be well attached and spread on the surface after 5 days of incubation. The results showed an inverse relation of cell viability with the surface roughness of pellets, and cells were seen to attach and spread along the direction of scratches.
KW - Bioactive glass
KW - Crystallization
KW - Solubility
KW - Cytocompatibility
KW - Surface roughness
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598257
DO - https://doi.org/10.1016/j.oceram.2024.100586
SN - 2666-5395
VL - 18
SP - 1
EP - 8
PB - Elsevier Ltd.
AN - OPUS4-59825
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scholz, Philipp
A1 - Falkenhagen, Jana
A1 - Wachtendorf, Volker
A1 - Brüll, Robert
A1 - Simon, Franz-Georg
T1 - Investigation on the Durability of a Polypropylene Geotextile under Artificial Aging Scenarios
N2 - Geosynthetics are widely used in various civil engineering applications, such as geotextiles in coastal protection, and display a sustainable alternative to natural mineral materials. However, the full benefits of using geosynthetics can only be gained with a long service lifetime of the products. With the use of added stabilizers to the polymers, service lifetimes can be achieved in the range of 100 years. Therefore, accelerated aging methods are needed for the assessment of the long-term performance of geotextiles. In the present study, the behavior of geosynthetic materials made of polypropylene was investigated under artificial aging conditions involving elevated temperatures ranging from 30 to 80 °C, increased oxygen pressures ranging from 10 to 50 bar in water-filled autoclaves, and UV irradiation under atmospheric conditions. ATR-IR spectroscopy was employed to detect the increase in the carbonyl index over various aging durations, indicating the oxidative degradation of the geotextile. The most pronounced increase was observed in the case of aging through UV irradiation, followed by thermal aging. Elevated pressure, on the other hand, had a lower impact on oxidation. High-temperature size exclusion chromatography was utilized to follow the reduction in molar mass under different degradation conditions, and the results were consistent with those obtained from ATR-IR spectroscopy. In polyolefins such as polypropylene, Hindered Amine Stabilizers (HAS) are used to suppress oxidation caused by UV radiation. The quantitative analysis of HAS was carried out using a UV/Vis method and HPLC. The degradation of UV stabilizers during the aging of geotextiles is responsible for the oxidation and the reduction in the molar mass of polypropylene. From the results, it can be concluded that applications of PP geotextile without soil or sand cover might cause the risk of the formation of microplastic particles. Material selection, design, and maintenance of the construction must follow best practices, including the system’s removal or replacement at end-of-life. Otherwise, a sustainable use of geotextiles in civil engineering is not possible.
KW - Geotextiles
KW - Microplastic
KW - Size exclusion chromatography
KW - Accelerated aging
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599739
DO - https://doi.org/10.3390/su16093559
SN - 2071-1050
VL - 16
IS - 9
SP - 1
EP - 15
PB - MDPI AG
CY - Basel
AN - OPUS4-59973
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bayerlein, Bernd
A1 - Schilling, Markus
A1 - von Hartrott, Philipp
A1 - Waitelonis, Jörg
T1 - Semantic integration of diverse data in materials science: Assessing Orowan strengthening
N2 - AbstractThis study applies Semantic Web technologies to advance Materials Science and Engineering (MSE) through the integration of diverse datasets. Focusing on a 2000 series age-hardenable aluminum alloy, we correlate mechanical and microstructural properties derived from tensile tests and dark-field transmission electron microscopy across varied aging times. An expandable knowledge graph, constructed using the Tensile Test and Precipitate Geometry Ontologies aligned with the PMD Core Ontology, facilitates this integration. This approach adheres to FAIR principles and enables sophisticated analysis via SPARQL queries, revealing correlations consistent with the Orowan mechanism. The study highlights the potential of semantic data integration in MSE, offering a new approach for data-centric research and enhanced analytical capabilities.
KW - Semantic Interoperability
KW - Knowledge Graph
KW - Orowan Mechanism
KW - Aluminum Alloy Aging
KW - Ontology
KW - Semantic Data Integration
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599780
DO - https://doi.org/10.1038/s41597-024-03169-4
VL - 11
IS - 1
SP - 1
EP - 12
PB - Springer Science and Business Media LLC
AN - OPUS4-59978
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ratkovac, Mirjana
A1 - Gerards-Wünsche, Paul
A1 - Thiele, Marc
A1 - Brackrock, Daniel
A1 - Stamm, Michael
T1 - Detection and monitoring of the fatigue crack growth on welds – Application-oriented use of NDT methods
N2 - Early detection of fatigue cracks and accurate measurements of the crack growth play an important role in the maintenance and repair strategies of steel structures exposed to cyclic loads during their service life. Observation of welded connections is especially of high relevance due to their higher susceptibility to fatigue damage. The aim of this contribution was to monitor fatigue crack growth in thick welded specimens during fatigue tests as holistically as possible, by implementing multiple NDT methods simultaneously in order to record the crack initiation and propagation until the final fracture. In addition to well-known methods such as strain gauges, thermography, and ultrasound, the crack luminescence method developed at the Bundesanstalt für Materialforschung und -prüfung (BAM), which makes cracks on the surface particularly visible, was also used. For data acquisition, a first data fusion concept was developed and applied in order to synchronize the data of the different methods and to evaluate them to a large extent automatically. The resulting database can ultimately also be used to access, view, and analyze the experimental data for various NDT methods. During the conducted fatigue tests, the simultaneous measurements of the same cracking process enabled a comprehensive comparison of the methods, highlighting their individual strengths and limitations. More importantly, they showed how a synergetic combination of different NDT methods can be beneficial for implementation in large-scale fatigue testing but also in monitoring and inspection programs of in-service structures - such as the support structures of offshore wind turbines.
T2 - Fatigue Design 2023 (FatDes 2023)
CY - Senlis, France
DA - 29.11.2023
KW - Fatigue
KW - Welded
KW - NDT
KW - Crack growth
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600238
DO - https://doi.org/10.1016/j.prostr.2024.03.062
VL - 57
SP - 560
EP - 568
PB - Elsevier B.V.
AN - OPUS4-60023
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Li, Z.
A1 - Raab, A.
A1 - Kolmangadi, Mohamed Aejaz
A1 - Busch, M.
A1 - Grunwald, M.
A1 - Demel, F.
A1 - Bertram, F.
A1 - Kityk, A. V.
A1 - Schönhals, Andreas
A1 - Laschat, S.
A1 - Huber, P.
T1 - Self-Assembly of Ionic Superdiscs in Nanopores
N2 - Discotic ionic liquid crystals (DILCs) consist of self-assembled superdiscs of cations and anions that spontaneously stack in linear columns with high one-dimensional ionic and electronic charge mobility, making them prominent model systems for functional soft matter. Compared to classical nonionic discotic liquid crystals, many liquid crystalline structures with a combination of electronic and ionic conductivity have been reported, which are of interest for separation membranes, artificial ion/proton conducting membranes, and optoelectronics. Unfortunately, a homogeneous alignment of the DILCs on the macroscale is often not achievable, which significantly limits the applicability of DILCs. Infiltration into nanoporous solid scaffolds can, in principle, overcome this drawback. However, due to the experimental challenges to scrutinize liquid crystalline order in extreme spatial confinement, little is known about the structures of DILCs in nanopores. Here, we present temperaturedependent high-resolution optical birefringence measurement and 3D reciprocal space mapping based on synchrotron X-ray scattering to investigate the thermotropic phase behavior of dopamine-based ionic liquid crystals confined in cylindrical channels of 180 nm diameter in macroscopic anodic aluminum oxide membranes. As a function of the membranes’ hydrophilicity and thus the molecular anchoring to the pore walls (edge-on or face-on) and the variation of the hydrophilic−hydrophobic balance between the aromatic cores and the alkyl side chain motifs of the superdiscs by tailored chemical synthesis, we find a particularly rich phase behavior, which is not present in the bulk state. It is governed by a complex interplay of liquid crystalline elastic energies (bending and splay deformations), polar interactions, and pure geometric confinement and includes textural transitions between radial and axial alignment of the columns with respect to the long nanochannel axis. Furthermore, confinement-induced continuous order formation is observed in contrast to discontinuous first-order phase transitions, which can be quantitatively described by Landau-de Gennes free energy models for liquid crystalline order transitions in confinement. Our observations suggest that the infiltration of DILCs into nanoporous solids allows tailoring their nanoscale texture and ion channel formation and thus their electrical and optical functionalities over an even wider range than in the bulk state in a homogeneous manner on the centimeter scale as controlled by the monolithic nanoporous scaffolds.
KW - Ionic Liquid Crystals
KW - Nanopropous materials
KW - Landau de-Gennes analysis
KW - X-ray scattering
KW - Optical birefringence
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600797
DO - https://doi.org/10.1021/acsnano.4c01062
SN - 1936-0851
VL - 18
IS - 22
SP - 14414
EP - 14426
PB - ACS
AN - OPUS4-60079
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Grundmann, Jana
A1 - Bodermann, Bernd
A1 - Ermilova, Elena
A1 - Weise, Matthias
A1 - Hertwig, Andreas
A1 - Klapetek, Petr
A1 - Rafighdoost, Jila
A1 - Pereira, Silvania F.
T1 - Optical and tactile measurements on SiC sample defects
N2 - Abstract. In power electronics, compound semiconductors with large bandgaps, like silicon carbide (SiC), are increasingly being used as material instead of silicon. They have a lot of advantages over silicon but are also intolerant of nanoscale material defects, so that a defect inspection with high accuracy is needed. The different defect types on SiC samples are measured with various measurement methods, including optical and tactile methods. The defect types investigated include carrots, particles, polytype inclusions and threading dislocations, and they are analysed with imaging ellipsometry, coherent Fourier scatterometry (CFS), white light interference microscopy (WLIM) and atomic force microscopy (AFM). These different measurement methods are used to investigate which method is most sensitive for which type of defect to be able to use the measurement methods more effectively. It is important to be able to identify the defects to classify them as critical or non-critical for the functionality of the end product. Once these investigations have been completed, the measurement systems can be optimally distributed to the relevant defects in further work to realize a hybrid analysis of the defects. In addition to the identification and classification of defects, such a future hybrid analysis could also include characterizations, e.g. further evaluation of ellipsometric data by using numerical simulations.
KW - Compound semiconductors
KW - Hybrid metrology
KW - Material defects
KW - Spectroscopic ellipsometry
KW - Scanning probe microscopy
KW - White-light interference microscopy
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601220
DO - https://doi.org/10.5194/jsss-13-109-2024
SN - 2194-878X
VL - 13
IS - 1
SP - 109
EP - 121
PB - Copernicus Publ.
CY - Göttingen
AN - OPUS4-60122
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - GEN
A1 - Hashemi, Seyedreza
A1 - Zscherpel, Uwe
T1 - Measurement of Focal Spots of X-ray Tubes Using a CT Reconstruction Approach on Edge Images of Large Holes and Comparison to Pinhole Imaging
N2 - The first Non-destructive testing (NDT) method which evolved in the industrial age was radiographic testing (RT). Among all NDT methods, RT is no exception, so there are still many issues for optimizations even today. One of them is the measurement of the focal spot of X-ray tubes. The size of the focal spot is critical for imaging, because it determines the spatial resolution in the X-ray image. The classical way to evaluate focal spots of X-ray tubes is by pinhole imaging using a camera obscura. But this method has a natural lower limit, which is defined by the diameter of the pinhole used (today min. 10 µm). Therefore, focal spot sizes lower than 50 µm diameter cannot be imaged and measured correctly. An alternative approach, which permits this, was investigated here using the edge unsharpness of holes much larger than the focal spot size. The results of both methods were compared using 3 different X-ray tubes.
KW - Reconstruction method
KW - Radiographic testing (RT) using X-rays
KW - Focal spot measurement
KW - Edge unsharpness
KW - X-ray tubes
KW - Pinhole imaging
KW - Computed Tomography (CT)
KW - Focal Spot (FS)
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608646
DO - https://doi.org/10.58286/29556
SN - 2941-4989
SP - 1
EP - 9
PB - NDT.net
CY - Berlin, Germany
AN - OPUS4-60864
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - da Costa, P. F. G. M.
A1 - Merízio, L. G.
A1 - Wolff, N.
A1 - Terraschke, H.
A1 - de Camargo, Andrea Simone Stucchi
T1 - Real-time monitoring of CdTe quantum dots growth in aqueous solution
N2 - Quantum dots (QDs) are remarkable semiconductor nanoparticles, whose optical properties are strongly size-dependent. Therefore, the real-time monitoring of crystal growth pathway during synthesis gives an excellent opportunity to a smart design of the QDs luminescence. In this work, we present a new approach for monitoring the formation of QDs in aqueous solution up to 90 °C, through in situ luminescence analysis, using CdTe as a model system. This technique allows a detailed examination of the evolution of their light emission. In contrast to in situ absorbance analysis, the in situ luminescence measurements in reflection geometry are particularly advantageous once they are not hindered by the concentration increase of the colloidal suspension. The synthesized particles were additionally characterized using X-ray diffraction analysis, transition electron microscopy, UV-Vis absorption and infrared spectroscopy. The infrared spectra showed that 3-mercaptopropionic acid (MPA)-based thiols are covalently bound on the surface of QDs and microscopy revealed the formation of CdS. Setting a total of 3 h of reaction time, for instance, the QDs synthesized at 70, 80 and 90 °C exhibit emission maxima centered at 550, 600 and 655 nm. The in situ monitoring approach opens doors for a more precise achievement of the desired emission wavelength of QDs.
KW - CdTe quantum dots
KW - In situ synthesis
KW - Real time growth control
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603596
DO - https://doi.org/10.1038/s41598-024-57810-8
SN - 2045-2322
VL - 14
IS - 1
SP - 1
EP - 11
PB - Springer Science and Business Media LLC
AN - OPUS4-60359
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zhang, Fengchan
A1 - Oiticica, Pedro Ramon Almeida
A1 - Abad-Arredondo, Jaime
A1 - Arai, Marylyn Setsuko
A1 - Oliveira, Osvaldo N.
A1 - Jaque, Daniel
A1 - Fernandez Dominguez, Antonio I.
A1 - de Camargo, Andrea Simone Stucchi
A1 - Haro-González, Patricia
T1 - Brownian Motion Governs the Plasmonic Enhancement of Colloidal Upconverting Nanoparticles
N2 - Upconverting nanoparticles are essential in modern photonics due to their ability to convert infrared light to visible light. Despite their significance, they exhibit limited brightness, a key drawback that can be addressed by combining them with plasmonic nanoparticles. Plasmon-enhanced upconversion has been widely demonstrated in dry environments, where upconverting nanoparticles are immobilized, but constitutes a challenge in liquid media where Brownian motion competes against immobilization.
This study employs optical tweezers for the three-dimensional manipulation of an individual upconverting nanoparticle, enabling the exploration of plasmon-enhanced upconversion luminescence in water. Contrary to expectation, experiments reveal a long-range (micrometer scale) and moderate (20%) enhancement in upconversion luminescence due to the plasmonic resonances of gold nanostructures. Comparison between experiments and numerical simulations evidences the key role of Brownian motion. It is demonstrated how the three-dimensional Brownian fluctuations of the upconverting nanoparticle lead to an “average effect” that explains the magnitude and spatial extension of luminescence enhancement.
KW - Upconversion
KW - Plasmon enhancement
KW - Optical tweezers
KW - Brownian motion
KW - Nanoparticles
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603551
DO - https://doi.org/10.1021/acs.nanolett.4c00379
VL - 24
IS - 12
SP - 3785
EP - 3792
PB - American Chemical Society (ACS)
AN - OPUS4-60355
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Held, Mathias
A1 - Bulling, Jannis
A1 - Lugovtsova, Yevgeniya
A1 - Prager, Jens
T1 - Determination of isotropic elastic constants from dispersion images based on ultrasonic guided waves by using neural networks
N2 - This article presents a method to use the dispersive behavior of ultrasonic guided waves and neural networks to determine the isotropic elastic constants of plate-like structures through dispersion images. Therefore, two different architectures are compared: one using convolutions and transfer learning based on the EfficientNetB7 and a Vision Transformer-like approach. To accomplish this, simulated and measured dispersion images are generated, where the first is applied to design, train, and validate and the second to test the neural networks. During the training of the neural networks, distinct data augmentation layers are employed to introduce artifacts appearing in measurement data into the simulated data. The neural networks can extrapolate from simulated to measured data using these layers. The trained neural networks are assessed using dispersion images from seven known material samples. Multiple variations of the measured dispersion images are tested to guarantee the prediction stability. The study demonstrates that neural networks can learn to predict the isotropic elastic constants from measured dispersion images using only simulated dispersion images for training and validation without needing an initial guess or manual feature extraction, independent of the measurement setup. Furthermore, the suitability of the different architectures for generating information from dispersion images in general is discussed.
KW - Ultrasonic guided waves
KW - Dispersion
KW - Elastic constants
KW - Neural networks
KW - Image processing
KW - Vision transformer
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607090
DO - https://doi.org/10.1016/j.ultras.2024.107403
SN - 0041-624X
VL - 143
SP - 1
EP - 48
PB - Elsevier B.V.
AN - OPUS4-60709
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ulrich, A. S.
A1 - Kasatikov, S.
A1 - König, T.
A1 - Fantin, Andrea
A1 - Margraf, J. T.
A1 - Galetz, M. C.
T1 - Decreased Metal Dusting Resistance of Ni-Cu Alloys by Fe and Mn Additions
N2 - Ni-Cu alloys are promising for application at temperatures between 400–900 °C and reducing atmospheres with high C-contents. Typically, under such conditions, metallic materials in contact with the C-rich atmosphere are degraded by a mechanism called metal dusting (MD). Ni-Cu-alloys do not form protective oxide scales, but their resistance is attributed to Cu, which catalytically inhibits the C-deposition on the surface. Adding other alloying elements, such as Mn or Fe, was found to enhance the MD attack of Ni-Cu alloys again. In this study, the effect of the Mn and Fe is divided into two affected areas: the surface and the bulk. The MD attack on binary Ni-Cu alloys, model alloys with Fe and Mn additions, and commercial Monel Alloy 400 is experimentally demonstrated. The surface electronic structure causing the adsorption and dissociation of C-containing molecules is investigated for model alloys. Analytical methods such as scanning electron microscopy combined with energy-dispersive X-ray spectroscopy, electron probe microanalysis combined with wavelength-dispersive X-ray spectroscopy, X-ray diffraction analysis, and near-edge X-ray absorption fine structure measurements were used. The results are correlated to CALPHAD calculations and atomistic simulations combining density functional theory calculations and machine learning. It is found that the Cu content plays a significant role in the surface reaction. The effect of Mn and Fe is mainly attributed to oxide formation. A mechanism explaining the enhanced attack by adding both Fe and Mn is proposed.
KW - Metal Dusting
KW - XANES
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608226
DO - https://doi.org/10.1007/s11085-024-10263-w
SN - 2731-8397
SP - 1
EP - 14
PB - Springer Science and Business Media LLC
AN - OPUS4-60822
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Omar, Hassan
A1 - Ahamadi, Shayan
A1 - Hülagü, Deniz
A1 - Hidde, Gundula
A1 - Hertwig, Andreas
A1 - Szymoniak, Paulina
A1 - Schönhals, Andreas
T1 - Investigations of the adsorbed layer of polysulfone: Influence of the thickness of the adsorbed layer on the glass transition of thin films
N2 - This work studies the influence of the adsorbed layer on the glass transition of thin films of polysulfone. Therefore, the growth kinetics of the irreversibly adsorbed layer of polysulfone on silicon substrates was first investigated using the solvent leaching approach, and the thickness of the remaining layer was measured with atomic force microscopy. Annealing conditions before leaching were varied in temperature and time (0–336 h). The growth kinetics showed three distinct regions: a pre-growth step where it was assumed that phenyl rings align parallel to the substrate at the shortest annealing times, a linear growth region, and a crossover from linear to logarithmic growth observed at higher temperatures for the longest annealing times. No signs of desorption were observed, pointing to the formation of a strongly adsorbed layer.
Second, the glass transition of thin polysulfone films was studied in dependence on the film thickness using spectroscopic ellipsometry. Three annealing conditions were compared: two with only a tightly bound layer formed in the linear growth regime and one with both tightly bound and loosely adsorbed layers formed in the logarithmic growth regime. The onset thickness and increase in the glass transition temperature increases with annealing time and temperature. These differences were attributed to the distinct conformations of the formed adsorbed layers.
KW - Glass transition
KW - Adsorbed Layer
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607701
DO - https://doi.org/10.1063/5.0223415
SN - 0021-9606
VL - 161
IS - 5
SP - 1
EP - 12
PB - AIP Publishing
AN - OPUS4-60770
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Andrés Arcones, Daniel
A1 - Weiser, M.
A1 - Koutsourelakis, P.-S.
A1 - Unger, Jörg F.
T1 - Model bias identification for Bayesian calibration of stochastic digital twins of bridges
N2 - Simulation-based digital twins must provide accurate, robust, and reliable digital representations of their physical counterparts. Therefore, quantifying the uncertainty in their predictions plays a key role in making better-informed decisions that impact the actual system. The update of the simulation model based on data must then be carefully implemented. When applied to complex structures such as bridges, discrepancies between the computational model and the real system appear as model bias, which hinders the trustworthiness of the digital twin and increases its uncertainty. Classical Bayesian updating approaches aimed at inferring the model parameters often fail to compensate for such model bias, leading to overconfident and unreliable predictions. In this paper, two alternative model bias identification approaches are evaluated in the context of their applicability to digital twins of bridges. A modularized version of Kennedy and O'Hagan's approach and another one based on Orthogonal Gaussian Processes are compared with the classical Bayesian inference framework in a set of representative benchmarks. Additionally, two novel extensions are proposed for these models: the inclusion of noise-aware kernels and the introduction of additional variables not present in the computational model through the bias term. The integration of these approaches into the digital twin corrects the predictions, quantifies their uncertainty, estimates noise from unknown physical sources of error, and provides further insight into the system by including additional pre-existing information without modifying the computational model.
KW - Gaussian process
KW - KOH
KW - Bayesian updating
KW - Digital twins
KW - Uncertainty quantification
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615519
DO - https://doi.org/10.1002/asmb.2897
SN - 1526-4025
N1 - This work was supported by “C07 - Data driven model adaptation for identifying stochastic digital twins of bridges” from the Priority Program (SPP) 2388/1 “Hundred plus” of the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) - Project number 501811638.
VL - 417
IS - 3
SP - 1
EP - 26
PB - Wiley
CY - Chichester
AN - OPUS4-61551
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Reuter, T.
A1 - Wohlgemuth, F.
A1 - Bellon, Carsten
A1 - Hausotte, T.
T1 - Measurement-based Detector Characteristics for Digital Twins in aRTist 2
N2 - Various software products for the simulation of industrial X-ray radiography have been developed in recent years (e.g., aRTist 2, CIVA CT, Scorpius XLab, SimCT, Wilcore) and their application potential has been shown in numerous works. However, full systematic approaches to characterise a specific CT system for these simulation software products to obtain a truthful digital twin are still missing. In this contribution, we want to present two approaches to obtain realistic grey values in X-ray projections in aRTist 2 simulations based on measured projections. In aRTist 2, the displayed grey value of a pixel is based on the energy density incident on that pixel.
The energy density is calculated based on the X-ray tube spectrum, the attenuation between source and detector as well as an energy-dependent sensitivity curve of the detector. The first approach presented in this contribution uses the sensitivity curve as a free modelling parameter. We measured the signal response at different thicknesses of Al EN-AW6082 at different tube voltages (i.e., different tube spectra). We then regarded the grey values displayed by these projections as a data regression respectively an optimisation problem and obtained the sensitivity curve that is best able to reproduce the measured behaviour in aRTist 2. The resulting sensitivity curve does not necessarily hold physical meaning but is able to simulate the real system behaviour in the simulation software.
The second approach presented in this contribution is to estimate the sensitivity curve based on assumptions about the characteristics of the scintillation detector (e.g., scintillator material, scintillator thickness and signal processing characteristics). For this approach, a linear response function (linear relationship between the deposited energy per pixel and the resulting grey value) is assumed. If the detector characteristics, which affect the simulated deposited energy, are properly modelled, the slope and offset of the response function to match the measured grey values should be the same for different tube spectra. As the offset is constant and given by the grey values measured at no incident radiation, the slope is the remaining parameter to evaluate the success of the detector modelling. We therefore adapted the detector characteristics by changing the detector setup until the slope was nearly the same for all measured tube spectra. We are aware that the resulting parameters of the scintillator material and thickness might not be the real ones, but with those modelling parameters we are able to simulate realistic grey values in aRTist 2. Both of those approaches could potentially be a step forward to a full systematic approach for a digital twin of a real CT system in aRTist 2.
T2 - 20th World Conference on Non-Destructive Testing (WCNDT 2024)
CY - Incheon, South Korea
DA - 27.05.2024
KW - Digital Twin
KW - Computed Tomography
KW - Simulation
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-602046
DO - https://doi.org/10.58286/29910
SP - 1
EP - 10
PB - NDT.net
CY - Mayen, Germany
AN - OPUS4-60204
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
T1 - On the physical processes of mechanochemically induced transformations in molecular solids
N2 - Initiating or sustaining physical and chemical transformations with mechanical force – mechanochemistry – provides an opportunity for more sustainable chemical processes, and access to new chemical reactivity.
KW - Molecular solids
KW - Transformation
KW - Destabilisation
KW - Instabilities
KW - Common phenomenon
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-621755
DO - https://doi.org/10.1039/d4cc04062g
IS - 99
SP - 1
EP - 12
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-62175
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Casali, Lucia
A1 - Carta, Maria
A1 - Michalchuk, Adam
A1 - Delogu, Francesco
A1 - Emmerling, Franziska
T1 - Kinetics of the mechanically induced ibuprofen–nicotinamide co-crystal formation by in situ X-ray diffraction
N2 - Mechanochemistry is drawing attention from the pharmaceutical industry given its potential for sustainable material synthesis and manufacture. Scaling mechanochemical processes to industrial level remains a challenge due to an incomplete understanding of their underlying mechanisms. We here show how time-resolved in situ powder X-ray diffraction data, coupled with analytical kinetic modelling, provides a powerful approach to gain mechanistic insight into mechanochemical reactions. By using the ibuprofen–nicotinamide co-crystal mechanosynthesis as a benchmark system, we investigate the behaviour of the solids involved and identify the factors that promote the reaction. As mechanochemical mechanisms become increasingly clear, it promises to become a breakthrough in the industrial preparation of advanced pharmaceuticals.
KW - Mechanochemistry
KW - Kinetics
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608820
DO - https://doi.org/10.1039/D4CP01457J
SN - 1463-9084
VL - 26
SP - 22041
EP - 22048
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-60882
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Vogel, Christian
A1 - Roesch, Philipp
A1 - Wittwer, Philipp
A1 - Sommerfeld, Thomas
A1 - Riedel, Maren
A1 - Leube, Peter
A1 - Kalbe, Ute
A1 - Schoknecht, Ute
A1 - Simon, Franz-Georg
T1 - Per- and Polyfluoroalkyl Substances (PFAS) in Ski Waxes and Snow from Cross-Country Skiing in Germany - Comparative study of Sum Parameter and Target Analysis
N2 - Per- and polyfluoroalkyl substances (PFAS) are often environmentally exposed via discharge through human consumer products, such as ski waxes. In our study we analyzed various ski waxes from the 1980s and 2020s, to determine both the sum parameter values total fluorine (TF), extractable organically bound fluorine (EOF), hydrolysable organically bound fluorine (HOF) as well as targeted PFAS analysis. This showed that modern high-performance waxes contain up to 6 % TF, but also PFAS-free labelled ski waxes contain traces of PFAS with EOF/HOF values in the low mg kg-1 range. With the ban of all fluorine-based waxes with the start of the 2023/2024 winter season this will probably change soon. Moreover, we applied our analysis methods to snow samples from a frequently used cross country ski trail (Kammloipe) in the Ore Mountain region in Germany, assessing the potential PFAS entry/discharge through ski waxes. Melted snow samples from different spots were analyzed by the adsorbable organically bound fluorine (AOF) sum parameter and PFAS target analysis and confirmed the abrasion of the ski waxes into the snow. Moreover, on a PFAS hotspot also soil samples were analyzed, which indicate that PFAS from the ski waxes adsorb after snow melting into the soil.
KW - Combustion Ion Chromatography
KW - Per- and Polyfluoroalkyl substances (PFAS)
KW - Consumer Products
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612760
DO - https://doi.org/10.1016/j.hazadv.2024.100484
VL - 16
SP - 1
EP - 5
PB - Elsevier B.V.
AN - OPUS4-61276
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Roesch, Philipp
A1 - Schinnen, Andrea
A1 - Riedel, Maren
A1 - Sommerfeld, Thomas
A1 - Sawal, G.
A1 - Bandow, N.
A1 - Vogel, Christian
A1 - Kalbe, Ute
A1 - Simon, Franz-Georg
T1 - Investigation of pH-dependent extraction methods for PFAS in (fluoropolymer-based) consumer products: A comparative study between targeted and sum parameter analysis
N2 - Here, we report a comparative study of different sum parameter analysis methods for the extraction of per- and polyfluoroalkyl substances (PFAS) from manufactured consumer products, which can be measured by combustion ion chromatography (CIC). Therefore, a hydrolysis-based extraction method was further developed, which accounts for the addition of hydrolyzable covalently bound polyfluoroalkylated side-chain polymers (SFPs) to the extractable organic fluorine portion of the mass balance proposed as "hydrolyzable organically bound fluorine" (HOF). To test this hypothesis, the method was applied to 39 different consumer products containing fluoropolymers or monomeric PFAS taken from four different categories: outdoor textiles, paper packaging, carpeting, and permanent baking sheets. We also evaluated the method's efficiency by extracting four synthesized fluorotelomer polyacrylate reference compounds. The total fluorine (TF) and extractable organically bound fluorine (EOF) values were measured through CIC using established protocols. The TF values ranged from sub-ppb to %-levels, depending on the compound class. All samples showed results for hydrolyzed organofluorine (HOF) between 0.03 and 76.3 μg/g, while most EOF values were lower (