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- 2 Prozess- und Anlagensicherheit (53)
There is an urgent demand for reliable data on microplastic analysis, particularly on its physico-chemical properties as well as validated methodology to obtain such data. Through interlaboratory comparisons (ILCs) it becomes possible to assess accuracy and precision of methods by involving many laboratories around the world. At BAM, my tasks focused around organisation of an ILC on physico-chemical characterisation of microplastic detection methods under the international pre-standardisation platform VAMAS (www.vamas.org/twa45/) as Project 2 “Development of standardized methodologies for characterisation of microplastics with microscopy and spectroscopy methods” under the Technical Working Area TWA 45 “Micro and Nano Plastics in the Environment”.
With a proud number of 84 participants this ILC is able to provide superior statistical results. Thermoanalytical (Py-GC/MS and TED-GC/MS) and vibrational (µ-IR and µ-Raman) methods were asked for identification and quantification of microplastic test samples according to mass or particle number. Preliminary results indicate which methods show a higher accuracy and precision and reveal some sample preparation ideas which work best for microplastics characterisation. At the end of the ILC an overall plausibility of the results will be assessed.
Rapid tests and assays to be used outside of a laboratory for non-trained personal and also at a point of need are becoming increasingly important in areas such as health, food, security, or the environment. Specially on that regard, paper-based sensors are emerging as a new class of devices because they fulfil the requisites of the "World Health Organization" to be ASSURED: affordable, sensitive, specific, user-friendly, rapid and robust, equipment free and deliverable to end-users. The physical, chemical and mechanical properties of cellulose or glass fiber paper in combination with the facility of preparation are making these materials of great interest while looking for cost-efficient and green alternatives for device production technologies. To improve the sensitivity of these systems, a particularly promising approach is the employment of gated indicator delivery systems using preorganized nanoscopic solid structures incorporated on paper strips to produce an exponential amplification of the detectable signal. Having in mind these concepts, several examples of (bio)gated materials incorporated into sensing membranes will be presented for the detection of small organic molecules, having fluorescence or electrochemiluminescence signal as output signal. Compared with fluorescence, it has been demonstrated that the non-optical excitation has significantly reduced the background signal, and with the help of a portable potentiostat in combination with a home-made 3D-printed case fitted onto a smartphone, the sensitivity of the sensing system has been improved tremendously, from the lower ppb range (fluorescence) to the lower ppt range. With this study, the applicability of ECL detection on paper strips in combination with gated indicator-releasing materials has been demonstrated for the first time, presenting a novel synergistic match. Considering the modularity of the system developed, the platform technology potential is obvious, promising expansion of the general concept to many other analytes, applications and scenarios.
Conclusion et piste:
Il semblerait qu’il n’existe pas de corrélation entre le type d’encre utilisés et d’autres critères recherchés à part une marque de préférence personnelle, sauf en ce qui concerne des documents religieux, auquel cas une différence se fait en function de la communauté.
Les résultats réunis dans cette étude semble indiquer que les scribes achètent leur propre encre.
L’analyse des encres peut nous aider à retracer une chronologie de l’écriture et signature de certains documents juridiques.
Élargissement du corpus:
- Comparaison avec des documents écrits par la cour du Qadi
- Documents d’autres collections
- Avec d’autres documents contemporains (Génizah Afghane)
In recent years the BAM has been focusing on the characterization of the writing materials of the medieval Torah scrolls. The challenge imposed by the study of this specific type of manuscript led to designing and building dedicated stages to ensure the safety of the scrolls during the analysis. Furthermore, the identification of multiple corrections executed in apparently identical inks required broadening the standard two-step protocol of near infrared reflectography and X-ray fluorescence to include multispectral imaging. This work has prepared the division to participate in the large collaborative project “To roll: Materialisierte Heiligkeit (Materialised Holiness)” based at the Free University, Berlin.
The presentation will demonstrate the aims of the studies, preliminary results and the strategies adopted by the division 4.5 of the BAM.
Sprengversuche sind ein wesentliches Werkzeug, um die Eignung von Schutzobjekten und Bauteilen zum Schutz der Bevölkerung vor Anschlägen mit explosionsgefährlichen Stoffen wie Explosivstoffen, sogenannten „home-made-explosives“ (HME) und unkonventionellen Spreng- und Brandvorrichtungen (USBV) zu bewerten. Für forensische Zwecke werden oft Explosionsszenarien nachgebildet, um die Auswirkung von Anschlägen oder Unfällen genau untersuchen zu können. Feldversuche in Kombination mit numerischen Simulationen ermöglichen eine Charakterisierung der Belastung und Schädigung von Bauteilen und Strukturen unter hochdynamischen Explosionsbelastungen.
Auf dem Testgelände Technische Sicherheit (TTS) der BAM in Horstwalde, Brandenburg werden Sprengversuche im Real-Maßstab durchgeführt. Dabei werden Bauteile mit Messtechnik ausgestattet, um eine dynamische Strukturcharakterisierung mittels sensorbasierten Monitorings zu ermöglichen.
In diesem Vortrag werden am Beispiel einer Versuchskampagne mit einer Stahlbetonwand als Prüfkörper die Eignung verschiedener Prüfmethoden bei Sprengversuchen evaluiert. Es werden Messmethoden zur Charakterisierung der Explosionsereignisse, des globalen Strukturverhaltens sowie der lokalen Schädigung vorgestellt.
Die direkte Charakterisierung der Explosionsbelastung erfolgt mit Hilfe von piezo-elektrischen Druckaufnehmern (bündig mit der Oberfläche im Prüfkörper montiert) und High-Speed-Kameras. Die Beobachtung der explosionsinduzierten Reaktion des Bauteils während und nach dem Eintreffen der Stoßwelle erfolgt mittels Beschleunigungssensoren, Stereo-Fotogrammetrie sowie mit in den Prüfkörper eingebetteter verteilter faseroptischer Sensoren, mit Hilfe derer die Dehnungsraten im Bauteil zeit- und ortsaufgelöst gemessen werden können. Die faseroptischen Sensoren erlauben außerdem die örtlich hochaufgelöste Bestimmung statischer Dehnungsänderungen im Bauteil nach einem Versuch, sodass auch nicht sichtbare Schädigungen wie kleinste Risse detektiert und charakterisiert werden können. Vergleichende Messungen mit Ultraschall komplettieren die Schadenscharakterisierung. In unserem Beitrag diskutieren wir die Herausforderungen dieser Messungen sowie die Ergebnisse und Möglichkeiten der genannten komplementären Messmethoden.
This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures.
The first lecture presents a brief introduction to the context and peculiarities of such foundations, and then focuses on the particular case of axially loaded piles. This part is most relevant for the relatively slender piles of the multi-pile substructures (i.e. jackets and tripods). A clear distinction between physical phenomenology and practical design is drawn here.
Design challenges for Offshore wind-farms. From foundation mechanics to wind-farm aerodynamics
(2023)
This talk provides a brief introduction on general engineering design challenges for the offshore wind energy production. Some general features of the offshore wind-energy field from a civil engineering perspective are firstly presented, followed by a brief discussion of some of the main geomechanical issues for the foundation of the offshore turbines into the seabed.
In the following part, an overview of relevant fluid-structure interactions and some options for an efficient numerical analysis are provided, where the hydromechanical Wave–Tower interaction is firstly discussed. Then, some general aspects of the windfarm aerodynamics are introduced. On the one hand, some modelling possibilities for the wake analysis of single turbines and turbine groups are discussed. And on the other hand the relevance of such analyses for a proper windfarm layout optimization is pointed out.
In particular, this talk shows that: i) The performance and behavior of the turbine's foundation is often conditioned by the appearance of large deformations, fluid couplings and grain-scale phenomena, whereby specific physical testing (both in field and lab conditions) and ad-hoc simulation techniques can provide useful insights for design; ii) Numerical analysis of a turbine’s interaction with wind/waves is already affordable in engineering scales, while simplified models can already provide a useful insight into the windfarm aerodynamics. iii) Turbulent wake analysis is very relevant for the windfarm layout.
This presentation deals with the phenomenology and design of pile foundations for offshore wind turbines, and is divided into two lectures.
The second lecture continues with the case of laterally loaded offshore piles, which bears most relevance for the case of the monopile foundations. Here again, a clear separation between physical reality and design methods is intended.
Finally, the last part of the second lecture introduces several advanced topics which lie outside the classical design approaches, namely the hydromechanical coupling effects (i.e. the excess pore-pressure generation around the monopiles), the cyclic pile fatigue and the so-called pile setup (i.e. the time effects on the axial pile capacity). The relevance of the latter two topics is illustrated with experimental results from a field testing campaign on real large-scale piles.
Die Wasserstoffinfrastruktur ist eine zentraler Bestandteil der erfolgreichen Umsetzung der wasserstoffbasierten Energiewende. Dabei bilden Ferngasleitungen quasi das "Rückgrat" der Transportinfrastruktur großer Gasmengen. Dabei müssen unter Umständen Reparaturen an den Pipelines durchgeführt werden. Dabei ist in der Erdgasinfrastruktur das Schweißen an in Betrieb befindlichen (d.h. von Gas durchflossenen) Pipelines Stand der Technik. Es ist jedoch vollkommen offen, inwieweit diese Technik auf die reine Wasserstoffpipelines übertragbar sind. Hierzu leistet das Projekt H2SuD wichtige Beiträge zur Aufklärung des Einfluss eines Reparaturschweißprozesses auf die Wasserstoffaufnahme und Degradation im Betrieb befindlicher H2 Gasleitungen.
Several recent studies have revealed that the phase decomposition in medium- and high-entropy alloys is triggered by solute segregation at grain boundaries. The chemically complex nature of these alloys already clues that such segregation in materials should be something more than the interaction between solutes and grain boundary, but also affected by the solute-solute interactions during the segregation. In fact, experiments indicate the significance of such solute-solute interaction. Yet, the mechanisms of co-segregation in multi-component alloys are rather challenging to explore and rarely studied quantitatively. Recently, a CALPHAD-integrated density-based phase-field model has been proposed for studying grain boundary phenomena. Several applications of this model have shown its expansive capacity for investigating grain boundary segregation and phase behavior. In this talk, the applications of this model to studying co-segregation phenomena and grain boundary phase diagrams in multi-component alloys are presented ––the term ‘co-segregation’ here refers to co-evolution and any mutual interplay among the solutes and grain boundary during the segregation. In particular, the iron-based ternary and quaternary alloys are discussed. I show how a grain boundary may have its own miscibility gap and how this immiscibility can influence the co-segregation behavior. As an alternative to grain boundary phase diagrams, rather suited for binary and ternary alloys, a new concept of co-segregation maps for screening and segregation design in multi-component alloys is presented. Applying the co-segregation maps, the nonlinear Mn and Cr co-segregation in Fe-Co-Mn-Cr is discussed.
The research carried out at the Laboratory of Spectroscopy of Functional Materials at IFSC/USP, in Brazil, is focused on the synthesis and structural-property correlation of luminescent materials including rare-earth (RE) doped glasses, ceramics and hybrid host-guest materials. For the past five years, we have been particularly interested in the development of single- and multifunctional nanosystems based on core-shell upconversion nanoparticles (UCNP) associated with dyes, organometallic complexes and other organic molecules, for biophotonic and sensing applications. In these systems, we take advantage of energy transfer between the UCNPs and the molecules to either supress or enhance luminescent response. Examples include the possibility of bioimaging and photodynamic therapy of bacteria and cancer cells, simultaneous magnetothermia and thermometry, localized O2 sensing, fast detection and quantification of biological markers (e.g. kidney disease) and microorganisms. On what concerns the development of luminescent sensors - a recently started project, our aim is to develop paper-based platforms for point-of-care devices. In this presentation, an overview of our contributions for the past years and our future aims will be presented with several examples.
When it comes to dental treatments, success is not only measured by attained functionality but, to a large extent, the associated aesthetics. This can become challenging for certain restorations and implants due to the complex optical characteristic of a tooth, which reflects, absorbs, diffuses, transmits, and even emits light. Thus, to get acceptable aesthetic results, favourable shade matching of ceramic restorations and implants should be achieved by strict control of optical response, which translates into a materials design question. Optical response is affected by several factors such as the composition, crystalline content, porosity, additives, grain size and the angle of incidence of light on the dental ceramics. The properties to be characterized are colour (and its stability), translucency, opalescence, refractive index, and fluorescence. Several techniques can be applied for the characterization of these properties and in this presentation, an overview will be given. Moreover, particular emphasis will be given on the capacitation of less familiarized public to UV-Vis absorption and photoluminescence (PLE) spectroscopies that are versatile and widely employed for functional and structural characterization of glasses and glass ceramic materials.
O3BET Quality Protocols
(2023)
Presentation of the process-oriented approach for the development of the quality protocolls (standard operation procedures and work instructions) for the O3BETs. O3BETs are innovative testing facilities for building envelopes which are developed in the course of the Metabuilding Labs EU Horizon 2020 project.
Sustainable product policy is one pillar of the European Green Deal and the Circular Economy Action Plan. The European Commission is to begin to address recycling, recycled content and repair under the Ecodesign Directive and very likely in the announced European Sustainable Products Regulation. In addition, initiatives on recyclability and other aspects of sustainable products can be observed in France under the Ecomodulation Approach for some electrical and electronic products. Neither the Commission's ambitions nor the Ecomodulation Approach have so far led to a crucially better ecodesign of products.
Therefore, at the EU level, indices for reparability (already developed for smartphones and tablets), recyclability and recycled content of products are being discussed within the Ecodesign legislative framework in an attempt to achieve better ecodesign through advanced consumer purchasing decisions. The product standards requested by the European Commission to assess the recyclability (EN4555) and recycled content (EN4557) of energy-related products have already been published, but are purely based on a mass-based approach. Material-specific aspects such as the environmental impact or the financial, technical and redesign efforts required by manufacturers to facilitate the recycling and use of recycled materials are not addressed. Materials that are easy to recycle and use and have a high recycled content, such as copper, are treated in the same way as plastics that are difficult to recycle and use in products as post-consumer recycled plastics. Including such aspects would be essential to trigger environmentally relevant and significant improvements in product design.
Interaction of L-phenylalanine with Magnetic Metal-Organic Framework: Electrochemical Analysis
(2023)
As the basic units of proteins, the importance of amino acids in organisms is self-evident and therefore detection of the concentration of amino acids is significant in monitoring human health. For example, patients suffering from phenylketonuria should be able to monitor their phenylalanine (PHE) level in a rapid, decentralized, and affordable manner to avoid high levels of PHE in the body which can lead to a profound and irreversible mental disability. Herein, a magnetic and conductive Iron based metal–organic framework (MOF) is prepared using tetrahydroxyquinone and benzene dicarboxylic acid, dual ligands. The uncoordinated carboxyl groups provided the binding sites for PHE. Physicochemical properties of MOF were characterized by XRD, SEM, DLS and FTIR analyses. The effects of different operational parameters: pH (2, 4, 6, 7.2, 8.6, 10, 12), contact time and MOF concentration were optimized for best properties using cyclic voltametric technique. The 10 µl of 1mg/ml MOF (pH 8.6) in deionized water was used as working electrode on screen-printed gold electrode. The presence of new well-defined oxidation and reduction current peak in electrochemical signal of MOF-modified SPGE sensor vs. Ag/AgCl in phosphate buffer solution (pH 1.9) remarks the quantification of PHE. The analytical calibration curve for PHE showed a linear response with concentration in the oxidation and reduction peak current range from 50 to 1000 µM, with a limit of detection (LOD) of 35.16 µM.