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Detection of Wire Breaks using Acoustic Emission Analysis - The New Guideline SE 05 of the German Society for Non- Destructive Testing (DGZfP)
No full textAbstractSpannungsrisskorrosion stellt Brückenbetreiber vor immense Herausforderungen, da sie zu gravierenden Schäden an den Spanngliedern führen kann und gleichzeitig die Methoden zur frühzeitigen Schadenserkennung und Tragfähigkeitskontrolle stark eingeschränkt sind. In diesem Kontext hat sich die Schallemissionsanalyse (SEA) zur Detektion von Spanndrahtbrüchen als bedeutsame Methode etabliert. Diese Technologie bietet einzigartige Vorteile und kann einen wichtigen Beitrag zur Sicherstellung des Weiterbetriebs gefährdeter Bauwerke liefern. Gleichzeitig erfordert die Anwendung der SEA tiefgehende spezialisierte Fachkenntnisse. Mit der zunehmenden Verbreitung und dem steigenden Interesse an dieser Methode ist auch der Bedarf an standardisierten Prozessen und Qualitätskontrollen gewachsen. Diesen Bedarf hat der Fachausschuss Schallemissionsprüfung der DGZfP erkannt und die Richtlinie SE 05 entwickelt. Diese Richtlinie setzt klare Standards und bietet umfassende Anleitung für die Implementierung und Anwendung der Schallemissionsanalyse zur Detektion von Spanndrahtbrüchen.Stress corrosion cracking confronts bridge operators with immense challenges, as it can lead to severe damage to the tendons while the methods for early damage detection and load-bearing capacity control are highly limited. In this context, Acoustic Emission Analysis (AEA) has established itself as an important method for detecting wire breaks. This technology offers unique advantages and can make a vital contribution to ensuring the continued operation of endangered structures. However, the application of AEA requires deep specialized expertise. With the increasing adoption and growing interest in this method, the need for standardized processes and quality controls has also grown. The DGZfP’s Acoustic Emission Testing Committee recognized this need and developed Guideline SE 05. This guideline sets clear standards and provides comprehensive guidance for the implementation and application of Acoustic Emission Analysis for detecting wire breaks
FIORA: Local neighborhood-based prediction of compound mass spectra from single fragmentation events
No full textNon-targeted metabolomics holds great promise for advancing precision medicine and biomarker discovery. However, identifying compounds from tandem mass spectra remains a challenging task due to the incomplete nature of spectral reference libraries. Augmenting these libraries with simulated mass spectra can provide the necessary references to resolve unmatched spectra, but generating high-quality data is difficult. In this study, we present FIORA, an open-source graph neural network designed to simulate tandem mass spectra. Our main contribution lies in utilizing the molecular neighborhood of bonds to learn breaking patterns and derive fragment ion probabilities. FIORA not only surpasses state-of-the-art fragmentation algorithms, ICEBERG and CFM-ID, in prediction quality, but also facilitates the prediction of additional features, such as retention time and collision cross section. Utilizing GPU acceleration, FIORA enables rapid validation of putative compound annotations and large-scale expansion of spectral reference libraries with high-quality predictions
Optical biosensor using free form prototyped elements for targeted explosives immunodetection
No full textEnsuring the safety and security of citizens necessitates a considerable investment of resources and the development of innovative tools by national and international agencies and governments, particularly in the context of explosives detection [1]. The necessity for the detection of improvised explosive devices (IEDs) and homemade explosives (HMEs) at the point of suspicion has increased exponentially due to the simplicity with which the precursors can be obtained, and the reagents synthesised. The restricted availability of immunoanalytical instruments for the detection of homemade explosives (HMEs) offers a valuable opportunity for the development of innovative devices that can rapidly identify and recognise the target analyte with high specificity and sensitivity [2].
In this study, we present the development of an optical biosensor for highly specific and sensitive HME detection. The immunoassay system is situated within a matrix that is permeable to the target analyte and transparent to light, which enables the interrogation via fluorescence. The immunoanalytical system's readout is achieved through the utilisation of supercritical angle fluorescence (SAF), an advanced microscopy technique. To this end, we employed recent, commercially available high-resolution (less than 22 μm) liquid crystal display SLA printers to fabricate a free-form parabolic optical element with a high refractive index (RI greater than 1.5) and transmission values exceeding 90% from commercial photo-resins. The objective is to develop a new generation of sensors that can not only meet the requirements of trace detection but also be used for substance identification. The combination of immunoanalytical recognition with SAF detection offers a modular and versatile solution that is particularly well suited to the measurement of target analytes at trace levels
Black fungi: Robust all-rounders for biotechnology
No full textKnufia petricola ist ein gesteinsbesiedelnder Pilz aus der polyphyletischen Gruppe der schwarzen Pilze. Diese Pilze entwickelten außergewöhnliche – und bisher kaum erforschte – Fähigkeiten, in verschiedenen extremen Umgebungen zu gedeihen. Die Nutzung der genetischen Vielfalt des Genoms von schwarzen Pilzen und die Nutzung von K. petricola als alternativer Wirt für die Produktion von Enzymen und Sekundärmetaboliten eröffnen Perspektiven für die Nutzung dieser bislang wenig bekannten Pilze für biotechnologische Anwendungen.Knufia petricola is a rock-inhabiting fungus belonging to the polyphyletic group of black fungi. These fungi developed extraordinary – and so far hardly studied – capabilities to thrive in different extreme environments. Accessing the genetic diversity of black fungal genomes and using K. petricola as an alternative host for producing enzymes and secondary metabolites opens perspectives for utilizing these so far little recognized fungi for biotechnological applications
Components of digital twins in the operation and maintenance management of traffic bridges
No full textDigitale Zwillinge werden zukünftig ein integraler Bestandteil des Erhaltungsmanagements von Verkehrsbrücken sein. In diesem Beitrag wird argumentiert, dass sie nicht nur als digitale Abbilder physikalischer Bauwerke verstanden werden sollten, sondern als eine umfassende digitale Methode, die durch die Integration von Datenerfassung, Erhaltungsmaßnahmen, Datenmanagement, Bauwerksbewertung und Entscheidungsunterstützung die Bauwerksüberwachung und ‐erhaltung verbessert. In diesem Zusammenhang wird betont, dass der Übergang von der reaktiven zur prädiktiven Erhaltung durch den Einsatz von Digitalen Zwillingen nur dann realisierbar ist, wenn neben den erforderlichen diagnostischen und prognostischen Zustandsanalysen auch Methoden zur Optimierung von Entscheidungen über Datenerfassung und Erhaltungsmaßnahmen implementiert werden. Zur Veranschaulichung der Diskussion werden in diesem Beitrag exemplarisch zwei Bestandteile eines Digitalen Zwillings für das Erhaltungsmanagement von Verkehrsbrücken am Beispiel einer Eisenbahnbrücke demonstriert. Dabei wird zum einen gezeigt, wie Monitoringdaten mittels eines Datenmanagementsystems strukturiert verwaltet und für angeknüpfte Analysen bereitgestellt werden. Zum anderen erfolgt im Rahmen einer bauwerksspezifischen Einwirkungsermittlung eine Zugidentifikation anhand von gemessenen Schwellenschwingungen.Digital twins will become an integral part of the operation and maintenance management of traffic bridges in the future. This paper argues that they should not only be understood as digital representations of physical structures but as a digital methodology that enhances the operation and maintenance of bridges through the integration of data collection, maintenance actions, data management, structural assessment, and decision support. In this context, it is emphasized that the transition from reactive to predictive maintenance using digital twins can only be achieved if, in addition to the necessary diagnostic and prognostic condition analyses, methods for optimizing decisions on data collection and maintenance actions are also implemented. To illustrate this discussion, two key components of a digital twin for the operation and maintenance management of traffic bridges are demonstrated using a railway bridge as an example. First, it is shown how monitoring data can be systematically managed and made available for subsequent analyses through a data management system. Second, train identification based on measured sleeper vibrations is conducted as part of an object-specific load assessment
Probabilistische Systemidentifikation einer Versuchsstruktur für Substrukturen von Offshore-Windenergieanlagen mit statischen und dynamischen Messdaten
No full textIn diesem Beitrag wird ein probabilistischer Ansatz zur Systemidentifikation für Tragstrukturen von Offshore-Windkraftanlagen vorgestellt. Der Schwerpunkt der Forschung liegt auf der Integration von globalen Systemantworten in Form von Eigenfrequenzen und -formen sowie Verschiebungen und Dehnungen als lokale Messdaten. Die unterschiedlichen Daten werden kombiniert für die Aktualisierung der Parameter eines Finite-Elemente-Modells genutzt. Zu diesem Zweck wird ein probabilistischer Ansatz nach Bayes verfolgt, um Vorwissen sowie Unsicherheiten einzubeziehen. Die Methodik wird bei einer Versuchsstruktur angewandt, die eine Jacket-Substruktur von Offshore-Windenergieanlagen nachbildet. Eine Systemidentifikation mit Hilfe von Überwachungsdaten ist wertvoll für Jacket-Substrukturen, da eine Zustandsanalyse für die Gewährleistung der strukturellen Integrität unerlässlich ist, aber hinsichtlich der schwierigen Offshore-Bedingungen möglichst effizient sein muss. In diesem Zusammenhang schafft diese Arbeit die Grundlage für eine Schadenserkennung, eine verbesserte Vorhersage der Ermüdungslebensdauer und optimierte Instandhaltungsstrategien. Während das Modell hinsichtlich der statischen Messdaten erfolgreich aktualisiert werden kann, sind Schwierigkeiten bei der Identifizierung der dynamischen Systemeigenschaften erkennbar
LA-ICP-ToF-MS imaging of slags from lithium battery recycling
No full textThe global demand for critical raw materials is increasing drastically as a consequence of the green energy transition and digitalisation. Electromobility in particular requires large amounts of lithium for Li-ion batteries. To guarantee future resources for Li-ion battery production, efficient recycling processes are paramount in securing critical metals. One such recycling process is pyrometallurgical processing, where metals such as Co, Ni, and Cu are concentrated in the alloy melt and Li is mainly partitioned into the slag phase. Partitioning of Li into Li-rich mineral phases within the slag, which subsequently can be separated and further concentrated via hydrometallurgical processes, such as flotation, could enable efficient recovery of Li from recycling products. However, the precipitation of other mineral phases along Li-rich minerals that also scavenge Li from the melt would be a severe constraint. Spinel is a potential phase competing for Li as it appears as primary phase during solidification of the slag melt. Here, we show the influence of spinel crystallization on the distribution of Li in the five-component slag system Li-Mg-Al-Si-Ca. Slags were processed by aerodynamic levitation where pieces of a previously research synthetic Li-rich slag [1] were containerless liquified and subsequently cooled using different protocols. The frozen droplets were embedded in epoxy resin and subsequently analysed by LA-ICP-ToF-MS. All experiments resulted in formation of spinel crystals within the slag phase (Figure 1).
Overall, Li (cf. Fig 1left) and Si are enriched in the groundmass compared to the spinel phase in which Mg (cf. Fig. 1 right) and Al are strongly concentrated. Additionally, in sample P1 spinel crystals show zoning with increasing Li content and decreasing Mg content from core to rim, respectively (Figure 1). In contrast, no zoning is observed for Al in the spinel phase. The elemental maps reveal gradually increasing concentrations of Li, Si, Al, and Mg towards the rim of the slag groundmass of sample P1. Distinct Li-rich silicate phases occur in the vicinity of spinel grains that are similar in composition to the Li- and Si-enriched rim of the slag spherule.
Our work highlights that spinel is the primary solidifying mineral phase in the investigated slag-system and that it scavenges Li from the slag melt during crystallization/cooling. Hence, future recycling protocols need to be adapted to take Li loss to spinel into account
Offshore Weathering Campaign on a North Sea Wind Farm Part One: Corrosivity Categories
No full textThe aim of this study is to investigate the corrosion behavior of materials and coatings in offshore environments, with a focus on determining the corrosivity categories at different locations on wind turbines. The collaboration between the authors enabled a 3‐year weathering campaign at the Hohe See and Albatros offshore wind farms in the North Sea. Metal panels were installed on two wind turbines to assess the corrosivity of different atmospheric conditions. Preliminary results indicate significant variations in corrosivity depending on location and material used, suggesting that current standards may not fully reflect real‐world conditions. The results of the study will help to optimize material selection and corrosion protection strategies for offshore wind farms, potentially extending their lifetime and reducing operating costs
Comparison of Commercially Available SIBs: Linking Material and Electrode Properties to Cell Performance
No full textAs the first commercial sodium-ion-batteries (SIBs) are available for purchase, it is possible to investigate material composition. Gaining an insight into the material composition of these SIBs is of interest not only for the classification of possible safety risks and hazards, but also in regards to recycling. Herein we report the preliminary investigations of the chemical and structural composition of first commercial SIB-cells. Two different SIB-cell types were compared in terms of electrode size, thickness, loading etc. Furthermore, the composition of the active materials and electrolyte was investigated and compared. Finally, the gained results were linked to the different data sheet performance of the two cell types
X-Ray absorption, refraction, and diffraction techniques for the characterization and non-destructive testing of materials
No full textThe combination of tomographic, microstructural data with other experimental techniques and with modeling is paramount, if we want to extract the maximum amount of information on material and component properties. In particular, quantitative image analysis, statistical approaches, direct discretization of tomographic reconstructions represent concrete possibilities to extend the power of the tomographic 3D representation to insights into the material and component performance. This logic thread equally holds for industrial and academic research and valorizes expensive experiments such as those carried out at synchrotron sources, which cannot be daily repeated.
I will show a few examples of possible use of X-ray tomographic data for quantitative assessment of damage evolution and microstructural properties, as well as for non-destructive testing. Examples of micro-structured inhomogeneous materials will be given, such as Composites, Ceramics, Concrete, and Additively manufactured parts. I will also show how X-ray refraction computed tomography (CT) can be highly complementary to classic absorption CT, being sensitive to internal interfaces.
Additionally, I will show how Neutron Diffraction, which is extremely well suited to the study of internal stresses, both residual and under external load, can well be coupled to the microstructural framework gained by CT, allowing understanding the microstructure-property relationships in materials