TY - JOUR
A1 - Shaheen, Sabahat
A1 - Hicke, Konstantin
A1 - Krebber, Katerina
T1 - Blast-Assisted Subsurface Characterisation Using a Novel Distributed Acoustic Sensing Setup Based on Geometric Phases
N2 - A novel DAS setup based on geometric phases in coherent heterodyne detection is applied for the first time to the characterisation of the Earth’s subsurface. In addition, an optimisation of the proposed setup in terms of its spatial resolution is also presented for the first time. The surface waves are generated by strong blasts of 25 kg of explosives at a dedicated test site. A 10 km dark fiber link in the vicinity of the test site connected to the test setup records the resulting strain signals. The spike-free and low-noise strain data thus obtained minimize post-processing requirements, making the setup a candidate for real-time seismic monitoring. An analysis of the dispersion characteristics of the generated surface waves is performed using a recently reported optimised seismic interferometric technique. Based on the dispersion characteristics, the shear wave velocities of the surface waves as a function of the depth profile of the Earth’s crust are determined using an optimised evolutionary algorithm.
KW - Geophysics
KW - Geometric Phase
KW - Distributed Fiber Optic Sensor
KW - Distributed Acoustic Sensing
KW - Earthquake Monitoring
KW - Seismology
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591913
DO - https://doi.org/10.3390/s24010030
VL - 24
IS - 1
SP - 1
EP - 12
PB - MDPI
AN - OPUS4-59191
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fröhlich-Nowoisky, J.
A1 - Bothen, N.
A1 - Backes, A. T.
A1 - Weller, Michael G.
A1 - Pöschl, U.
T1 - Oligomerization and tyrosine nitration enhance the allergenic potential of the birch and grass pollen allergens Bet v 1 and Phl p 5
N2 - Protein modifications such as oligomerization and tyrosine nitration alter the immune response to allergens and may contribute to the increasing prevalence of allergic diseases. In this mini-review, we summarize and discuss relevant findings for the major birch and grass pollen allergens Bet v 1 and Phl p 5 modified with tetranitromethane (laboratory studies), peroxynitrite (physiological processes), and ozone and nitrogen dioxide environmental conditions). We focus on tyrosine nitration and the formation of protein dimers and higher oligomers via dityrosine cross-linking and the immunological effects studied.
N2 - Proteinmodifikationen wie Oligomerisierung und Tyrosinnitrierung verändern die Immunantwort auf Allergene und tragen möglicherweise zur zunehmenden Prävalenz allergischer Erkrankungen bei. In diesem Mini-Review fassen wir relevante Befunde zu den wichtigsten Birken- und Gräserpollenallergenen Bet v 1 und Phl p 5 zusammen, die mit Tetranitromethan (Laborstudien), Peroxynitrit (physiologische Prozesse) und Ozon und Stickstoffdioxid (Umweltbedingungen). Wir konzentrieren uns auf die Tyrosin-Nitrierung und die Bildung von Proteindimeren und höheren Oligomeren durch Dityrosin-Vernetzung und deren immunologischen Auswirkungen.
KW - Allergy
KW - Nitration
KW - Protein oligomers
KW - Air pollution
KW - Ozone
KW - Nitrogen oxides
KW - Tyrosine
KW - Nitrotyrosine
KW - Dityrosine
KW - Dityrosine crosslinking
KW - Protein degradation
KW - Neoepitopes
KW - Neoallergen
KW - IgE
KW - Immunoglobulin E
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591453
DO - https://doi.org/10.3389/falgy.2023.1303943
VL - 4
SP - 1
EP - 8
PB - Frontiers Media
CY - Switzerland
AN - OPUS4-59145
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Simon, Franz-Georg
A1 - Scholz, Philipp
T1 - Assessment of the Long-Term Leaching Behavior of Incineration Bottom Ash: A Study of Two Waste Incinerators in Germany
N2 - The long-term leaching behavior of incineration bottom ash (IBA) was studied with large-scale samples from two German waste incinerators with grate technology. The observation period was up to 281 days. The aging processes proceeded faster in the outdoor storage of the samples. The dominant factor in the leaching behavior is the pH, which starts at values above 12 and decreases to values below 10 (outdoors, <11 indoors). Most heavy metals exhibit minimum solubility in this pH range. The solubility of Sb depends on the prevailing Ca concentration, due to the formation of low-soluble Ca antimonate. The very low sulfate concentrations observed in the leaching tests with fresh IBA could be explained by the presence of ettringite. In the course of the aging reaction, ettringite is transformed into gypsum. The results from batch tests were compared with those from column tests, showing reasonable agreement. Leaching dynamics can be better followed with column tests. All results confirm that the use of IBA is possible under German law.
KW - Aging
KW - Incineration bottom ash
KW - Leaching
KW - Secondary building materials
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591599
DO - https://doi.org/10.3390/app132413228
SN - 2076-3417
VL - 13
IS - 24
SP - 1
EP - 15
PB - MDPI AG
CY - Basel
AN - OPUS4-59159
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Häusler, F.
A1 - Stührenberg, J.
A1 - Neumann, Patrick P.
ED - Sigalov, K.
ED - Hagedorn, P.
ED - Schönfelder, P.
ED - Faltin, B.
ED - Zentgraf, S.
ED - Block, M.
T1 - Gasquellenlokalisierung mit Drohnenschwärmen
N2 - Gasquellenlokalisierungen (Gas Source Localization, GSL) tragen dazu bei, die Folgen von Industrieunfällen und Naturkatastrophen zu mildern. Während die GSL, wenn von Menschen durchgeführt, gefährlich und zeitaufwändig ist, können Schwärme von wendigen und kostengünstigen Nanodrohnen die Effizienz und Sicherheit der Suche erhöhen. Da die geringe Nutzlast von Nanodrohnen die Sensor- und Rechenressourcen einschränkt, werden Strategien zur Koordination des Roboterschwarms verwendet, die von biologischen Schwärmen, wie Kolonien sozialer Insekten, inspiriert sind. Die meisten Schwarm-GSL-Strategien verwenden das Maximum der Gaskonzentrationsverteilung zur Schätzung der Gasquellenposition. Experimente legen jedoch nahe, dass die Intermittenz der Gasverteilung vielversprechender ist. In diesem Beitrag wird eine neuartige GSL-Strategie für Schwärme vorgestellt, die auf Pheromonkommunikation und Intermittenz der Gasverteilung basiert. Die Agenten, d.h. die Nanodrohnen, emittieren Pheromonmarker in einer virtuellen Umgebung, wenn sie eine neue Gaswolke feststellen. Die Agenten werden durch virtuelle Kräfte gesteuert und nutzen abwechselnd das Wissen des Schwarms, indem sie dem Pheromongradienten folgen, oder erkunden den Suchraum, indem sie einen Zufallspunkt ansteuern. Zur Kollisionsvermeidung werden die Agenten durchgehend von anderen Agenten und Wänden abgestoßen. Die Strategie wurde auf drei Nanodrohnen implementiert und durch ein Experiment in einem Innenraum mit einer statischen Gasquelle validiert. Die Ergebnisse zeigen eine Verbesserung gegenüber maximabasierten Verfahren und geringe Lokalisierungsfehler in Windrichtung.
T2 - 34. Forum Bauinformatik 2023
CY - Bochum, Germany
DA - 06.08.2023
KW - Mobile Robotic Olfaction
KW - Bouts
KW - Mobile Sensorik
KW - Nanodrohnen
KW - Pheromonkommunikation
KW - Schwarmrobotik
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594320
DO - https://doi.org/10.13154/294-10088
SP - 168
EP - 175
AN - OPUS4-59432
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Temgoua, Ranil C.T.
A1 - Dontsi, Fabiola T.
A1 - Lebègue, Estelle
A1 - Thobie-Gautier, Christine
A1 - Tonlé, Ignas K.
A1 - Boujtita, Mohammed
T1 - Understanding the behavior of phenylurazole-tyrosine-click electrochemical reaction using hybrid electroanalytical techniques
N2 - In this work, the electrochemical behavior of 4-phenylurazole (Ph-Ur) was studied and the latter was used as a molecular anchor for the electrochemical bioconjugation of tyrosine (Y). Cyclic voltammetry (CV) and controlled potential coulometry (CPC) allowed the in-situ generation of the PTAD (4-phenyl-3 H-1,2,4-triazole-3,5(4 H)-dione) species from phenylurazole on demand for tyrosine electrolabeling. The chemoselectivity of the reaction was studied with another amino acid (lysine, Lys) and no changes in Lys were observed. To evaluate the performance of tyrosine electrolabeling, coulometric analyses at controlled potentials were performed on solutions of phenylurazole and the phenylurazole-tyrosine mixture in different proportions (2:1, 1:1, and 1:2). The electrolysis of the phenylurazole-tyrosine mixture in the ratio (1:2) produced a charge of 2.07 C, very close to the theoretical value (1.93 C), with high reaction kinetics, a result obtained here for the first time. The products obtained were identified and characterized by liquid chromatography coupled to high-resolution electrospray ionization mass spectrometry (LC-HRMS and LC- HRMS2). Two products were formed from the click reactions, one of which was the majority. Another part of this work was to study the electrochemical degradation of the molecular anchor 4-phenylazole (Ph-Ur). Four stable degradation products of phenylurazole were identified (C7H9N2O, C6H8N, C6H8NO, C14H13N4O2) based on chromatographic profiles and mass spectrometry results. The charge generated during the electrolysis of phenylurazole (two-electron process) (2.85 C) is inconsistent with the theoretical or calculated charge (1.93 C), indicating that secondary/parasitic reactions occurred during the electrolysis of the latter. In conclusion, the electrochemically promoted click phenylurazole-tyrosine reactions give rise to click products with high reaction kinetics and yields in the (1:2) phenylurazole-tyrosine ratios, and the presence of side reactions is likely to affect the yield of the click phenylurazole-tyrosine reaction.
KW - Clinical Biochemistry
KW - Spectroscopy
KW - Drug Discovery
KW - Pharmaceutical Science
KW - Analytical Chemistry
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599267
DO - https://doi.org/10.1016/j.jpba.2024.116147
VL - 245
SP - 1
EP - 8
PB - Elsevier BV
AN - OPUS4-59926
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mirtsch, Mona
T1 - Adoption of the information security management system standard ISO/IEC 27001 - A study among German organizations
N2 - Against the backdrop of numerous security breaches and cyber-attacks, organizations need to take measures to secure their data and information. However, the well-known management system standard ISO/IEC 27001 for information security has shown a lower adoption rate – in terms of annual ISO survey data – than was previously expected by scholars and practitioners. Through the lens of Rogers' diffusion of innovation theory, we consider the adoption of ISO/IEC 27001 as a 'preventive innovation' and aim to identify factors that help gain a better understanding of its adoption. Therefore, we conducted a survey among German organizations on the use and impact of management system standards, explicitly distinguishing between organizations that implement ISO/IEC 27001 and those that are additionally certified against this standard. This study provides insights and contributes to an advanced understanding of motives, impacts, barriers, and useful measures to increase adoption of ISO/IEC 27001. Our findings may be useful to organizations considering the adoption of this management system standard, to certification bodies providing certification services, and to policymakers seeking means to improve information security in organizations.
KW - Management science and operations research
KW - ISO/IEC 27001
KW - Management system standard
KW - Information security
KW - QI-FoKuS
KW - Certification
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594704
UR - http://ijqr.net/paper.php?id=1098
DO - https://doi.org/10.24874/ijqr17.03-08
SN - 1800-6450
SN - 1800-7473
VL - 17
IS - 3
SP - 747
EP - 768
PB - Center for Quality, University of Montenegro
CY - Podgorica
AN - OPUS4-59470
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zuffa, Caterina
A1 - Cappuccino, Chiara
A1 - Casali, Lucia
A1 - Emmerling, Franziska
A1 - Maini, Lucia
T1 - Liquid reagents are not enough for liquid assisted grinding in the synthesis of [(AgBr)(n-pica)]n
N2 - This study investigates the mechanochemical reactions between AgBr 3-picolylamine and 4-picolylamine. The use of different stoichiometry ratios of the reagents allows [(AgBr)(n-pica)]n and [(AgBr)2(n-pica)]n to be obtained, and we report the new structures of [(AgBr)2(3-pica)]n and [(AgBr)2(4-pica)]n which are characterized by the presence of the following: (a) infinite inorganic chains, (b) silver atom coordinated only by bromide atoms and (c) argentophilic interactions. Furthermore, we studied the interconversion of [(AgBr)(n-pica)]n/[(AgBr)2(n-pica)]n by mechanochemical and thermal properties. The in situ experiments suggest that [(AgBr)(3-pica)]n is kinetically favoured while [(AgBr)2(3-pica)]n is converted into [(AgBr)(3-pica)]n only with a high excess of the ligand. Finally, the liquid nature of the ligands is not sufficient to assist the grinding process, and the complete reaction is observed with the addition of a small quantity of acetonitrile.
KW - Mechanochemistry
KW - Complex
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594755
DO - https://doi.org/10.1039/d3cp04791a
SN - 1463-9076
SP - 1
EP - 10
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-59475
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zaytsev, D.
A1 - Funk, Alexander
T1 - On the crack evolutional in human dentin under uniaxial compression imaged by high resolution tomography
N2 - An observation of the fracture process in front of the crack tip inside a dentin sample by means of ex-situ X-ray computed tomography after uniaxial compression at different deformation values was carried out in this work. This ex-situ approach allowed the microstructure and fracturing process of human dentin to be observed during loading. No cracks are observed up to the middle part of the irreversible deformation in the samples at least visible at 0.4μm resolution. First cracks appeared before the mechanical stress reached the compression strength. The growth of the cracks is realized by connecting the main cracks with satellite cracks that lie ahead of the main crack tip and parallel its trajectory. When under the stress load the deformation in the sample exceeds the deformation at the compression strength of dentin, an appearance of micro-cracks in front of the main cracks is observed. The micro-cracks are inclined (~60°) to the trajectory of the main cracks. The further growth of the main cracks is not realized due to the junction with the micro-cracks; we assume that the micro-cracks dissipate the energy of the main crack and suppressed its growth. These micro-cracks serve as additional stress accommodations, therefore the samples do not break apart after the compression test, as it is usually observed under bending and tension tests.
KW - Dentin
KW - Crack evolution
KW - Compression strength
KW - Mechanical properties
KW - Microstructure
KW - Ex-situ X-ray computed tomography
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594810
DO - https://doi.org/10.18149/MPM.5152023_5
SN - 1605-8119
VL - 51
IS - 5
SP - 38
EP - 51
PB - Advanced Study Center
CY - St. Petersburg
AN - OPUS4-59481
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Asna Ashari, Parsa
A1 - Blind, Knut
T1 - The effects of hydrogen research and innovation on international hydrogen trade
N2 - Climate change and the pressure to decarbonize, as well as energy security concerns, have drawn the attention of policymakers and the industry to hydrogen energy. To ad-vance the hydrogen economy at a global scale, research and innovation progress is of significant importance, among others. However, previous studies have provided only lim-ited quantitative evidence of the effects of research and innovation on the formation of a global hydrogen market. Instead, they postulate rather than empirically support this rela-tionship. Therefore, this study analyzes the effects of research and innovation measured by scientific publications, patents, and standards on bilateral hydrogen trade flows for 32 countries between 1995 and 2019 in a gravity model of trade, using regression analyses and Poisson Pseudo Maximum Likelihood (PPML) estimation. The main results of the PPML estimation show that research and innovation progress is indeed associated with increased trade, especially with patenting and (international) standardization enhancing hydrogen export volumes. As policy implications, we derive that increased public R&D funding can help increase the competitiveness of hydrogen energy and boost market growth, along with infrastructure support and harmonized standards and regulations.
KW - Hydrogen supply
KW - Global hydrogen market
KW - Research and innovation
KW - Push and pull effects
KW - Hydrogen policies
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594875
DO - https://doi.org/10.1016/j.enpol.2023.113974
SN - 0301-4215
VL - 186
SP - 1
EP - 15
PB - Elsevier B.V.
AN - OPUS4-59487
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Andreoli, A. F.
A1 - Fantin, Andrea
A1 - Kasatikov, S.
A1 - Bacurau, V. P.
A1 - Widom, M.
A1 - Gargarella, P.
A1 - Mazzer, E. M.
A1 - Woodcock, T. G.
A1 - Nielsch, K.
A1 - Coury, F. G.
T1 - The impact of chemical short-range order on the thermophysical properties of medium- and high-entropy alloys
N2 - The unusual behavior observed in the coefficient of thermal expansion and specific heat capacity of CrFeNi, CoCrNi, and CoCrFeNi medium/high-entropy alloys is commonly referred to as the K-state effect. It is shown to be independent of the Curie temperature, as demonstrated by temperature-dependent magnetic moment measurements. CoCrFeNi alloy is chosen for detailed characterization; potential reasons for the K-state effect such as texture, recrystallization, and second-phase precipitation are ruled out. An examination of the electronic structure indicates the formation of a pseudo-gap in the Density of States, which suggests a specific chemical interaction between Ni and Cr atoms upon alloying. Hybrid Monte Carlo/Molecular Dynamic (MC/MD) simulations indicate the presence of non-negligible chemical short-range order (CSRO). Local lattice distortions are shown to be negligible, although deviations around Cr and Ni elements from those expected in a fully disordered structure are experimentally observed by X-ray absorption spectroscopy. The determined bonding distances are in good agreement with MC/MD calculations. A mechanism is proposed to explain the anomalies and calorimetric experiments and their results are used to validate the mechanism.
KW - Mechanical Engineering
KW - Mechanics of Materials
KW - General Materials Science
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595869
DO - https://doi.org/10.1016/j.matdes.2024.112724
SN - 0264-1275
VL - 238
SP - 1
EP - 15
PB - Elsevier B.V.
AN - OPUS4-59586
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - von Törne, Wipert Jannik
A1 - Steinhäuser, Lorin
A1 - Klyk-Seitz, Urszula-Anna
A1 - Piechotta, Christian
T1 - High-resolution mass spectrometric elucidation of electron ionization induced fragmentation pathways of methylated warfarin and selected hydroxylated species
N2 - The plant secondary metabolite families of coumarin and 4-hydroxy coumarin have a broad pharmacological spectrum ranging from antibacterial to anticancer properties. One prominent member of this substance class is the synthetic but naturally inspired anticoagulant drug and rodenticide warfarin (coumadin). A vast number of publications focus on the identification of warfarin and its major cytochrome P450-mediated phase I metabolites by liquid chromatography (LC) with mass spectrometry (MS) and tandem mass spectrometric (MS/MS) detection techniques. For the first time, electron ionization (EI) induced high-resolution quadrupole time-of-flight mass spectrometric (HR-qToF-MS) data of in-liner derivatized warfarin and selected hydroxylated species is provided in this study as an alternative to LC-MS/MS approaches. Furthermore, the characteristic fragments and fragmentation pathways of the analyzed methyl ethers are concluded. The obtained data of analytical standards, specific deuterated and 13C-labeled compounds prove inductive cleavage of the acyl or acetonyl side chain, methyl migration, and H-migration, along with consequential inductive cleavage as predominant fragmentation routes. Based on the HR-spectral data, commonalities and differences between the analyzed compounds and fragment groups were evaluated with future applicability in structure elucidation and spectra prediction of related compounds.
KW - High-resolution mass spectrometry
KW - Warfarin
KW - Hydroxy warfarin
KW - Fragmentation pathway
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596025
DO - https://doi.org/10.1016/j.ijms.2024.117220
SN - 1387-3806
VL - 499
SP - 1
EP - 7
PB - Elsevier B.V.
AN - OPUS4-59602
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - von Törne, Wipert Jannik
A1 - Klyk-Seitz, Urszula-Anna
A1 - Piechotta, Christian
T1 - Developing a GC-EI-MS/MS method for quantifying warfarin and five hydroxylated metabolites generated by the Fenton reaction
N2 - AbstractSince the 1950s, Warfarin has been used globally as both a prescription drug and a rodenticide. Research has shown that warfarin and other rodenticides are present in the environment and food chain. However, emerging contaminants are subject to degradation by biotic and abiotic processes and advanced oxidation processes. In some cases, detecting the parent compound may not be possible due to the formation of structurally changed species. This approach aims to identify hydroxylated transformation products of warfarin in a laboratory setting, even after the parent compound has undergone degradation. Therefore, the Fenton reaction is utilized to insert hydroxylation into the parent compound, warfarin, by hydroxyl and hydroperoxyl radicals generated by Fe2+/Fe3+ redox reaction with hydrogen peroxide. Using multiple reaction monitoring, a GC–MS/MS method, incorporating isotopically labeled reference compounds, is used to quantify the expected derivatized species. The analytes are derivatized using trimethyl-3-trifluoromethyl phenyl ammonium hydroxide, and the derivatization yield of warfarin is determined by using isotopically labeled reference compounds. The method has a linear working range of 30 to 1800 ng/mL, with detection limits ranging from 18.7 to 67.0 ng/mL. The analytes are enriched using a C18-SPE step, and the recovery for each compound is calculated. The Fenton reaction generates all preselected hydroxylated transformation products of warfarin. The method successfully identifies that 4′-Me-O-WAR forms preferentially under the specified experimental conditions. By further optimizing the SPE clean-up procedures, this GC–MS-based method will be suitable for detecting transformation products in more complex matrices, such as environmental water samples. Overall, this study provides a better understanding of warfarin’s degradation and offers a robust analytical tool for investigating its transformation products.
KW - Health, Toxicology and Mutagenesis
KW - Pollution
KW - Environmental Chemistry
KW - General Medicine
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595737
DO - https://doi.org/10.1007/s11356-024-32133-3
SN - 0944-1344
VL - 31
SP - 16986
EP - 16994
PB - Springer Science and Business Media LLC
AN - OPUS4-59573
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Choi, Ching-Yi
A1 - Lossada, F.
A1 - Walter, K.
A1 - Fleck-Kunde, T.
A1 - Behrens, S.
A1 - Meinelt, T.
A1 - Falkenhagen, Jana
A1 - Hiller, M.
A1 - Oschkinat, H.
A1 - Dallmann, A.
A1 - Taden, A.
A1 - Börner, H.G.
T1 - Organic transformation of lignin into mussel-inspired glues: next-generation 2K adhesive for setting corals under saltwater
N2 - The 2-methoxyphenol units (G-units) in lignin are modified by demethylation and oxidation to provide the activated lignin as one part of an advanced biobased two-component (2K) adhesive system, which exhibits promising shear strengths in dry and underwater applications. The activation of lignin is straightforward and generates quinones via demethylation and periodate oxidation. These act as Michael acceptors and react smoothly with multi-thiol-star polymers to yield thiol-catechol connectivities (TCCs). The mussel-inspired material platform acts as a very robust and versatile adhesive, combining low-cost and readily available lignin with multi-thiols to achieve outstanding adhesion strengths of up to 15 MPa in dry application. In particular, the 2K system is compatible with the marine biological environment and shows no acute toxicity to sensitive organisms such as fish eggs. Thus, one possible application of this material could be an adhesive for setting temperature-resistant corals in damaged reefs.
KW - Lignin modification
KW - Mussel-inspired adhesive systems
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594588
DO - https://doi.org/10.1039/d3gc03680d
SN - 1463-9270
SP - 1
EP - 15
PB - RSC
CY - Cambridge
AN - OPUS4-59458
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lu, Xin
A1 - Hicke, Konstantin
A1 - Krebber, Katerina
T1 - Distributed acoustic sensing to monitor ground motion/movement at multi-frequency bands
N2 - A novel distributed acoustic sensing technique is proposed that exploits both phase and amplitude of the Rayleigh backscattered light to quantify the environmental variation. The system employs a wavelength-scanning laser and an imbalanced Mach-Zehnder interferometer to acquire the reflection spectra and the phase of the detected light, respectively. Fading-free and low-frequency measurements are realized via the crosscorrelation of the reflection spectra. The discrete crosscorrelation is used to circumvent the nonlinear frequency sweeping of the laser. Based on the phase of the backscattered light, it is possible to quantify fast environmental variations. The whole system requires no hardware modification of the existing system and its functionality is experimentally validated. The proposed system has the potential to monitor ground motion/movement at very low frequency band like subsidence around mining areas and at high frequency band like earthquakes and vibrations induced by avalanches.
KW - Distributed acoustic sensing
KW - DAS
KW - Distributed fiber optic sensing
KW - Ground motion detection
KW - Subsidence monitoring
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596129
DO - https://doi.org/10.1109/JLT.2024.3358495
VL - 42
IS - 18
SP - 1
EP - 8
PB - Optical Society und IEEE Photonics Society
AN - OPUS4-59612
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kornev, Roman
A1 - Gornushkin, Igor B.
A1 - Shabarova, Lubov
A1 - Kadomtseva, Alena
A1 - Mochalov, Georgy
A1 - Rekunov, Nikita
A1 - Romanov, Sergey
A1 - Medov, Vitaly
A1 - Belousova, Darya
A1 - Maleev, Nikita
T1 - Plasma-Chemical Disposal of Silicon and Germanium Tetrachlorides Waste by Hydrogen Reduction
N2 - The processes of hydrogen reduction of silicon and germanium chlorides under the conditions of high-frequency (40.68 MHz) counteracted arc discharge stabilized between two rod electrodes are investigated. The main gas-phase and solid products of plasma-chemical transformations are determined. Thermodynamic analysis of SiCl4 + H2 and GeCl4 + H2 systems for optimal process parameters was carried out. Using the example of hydrogen reduction of SiCl4 by the method of numerical modeling, gas-dynamic and thermal processes for this type of discharge are investigated. The impurity composition of gas-phase and solid reaction products is investigated. The possibility of single-stage production of high-purity Si and Ge mainly in the form of compact ingots, as well as high-purity chlorosilanes and trichlorogermane, is shown.
KW - High-frequency arc discharge
KW - Hydrogen reduction
KW - Silicon chlorides
KW - Germanium chlorides
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594454
DO - https://doi.org/10.3390/sci6010001
VL - 6
IS - 1
SP - 1
EP - 12
PB - MDPI AG
AN - OPUS4-59445
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Esparza Mora, Margy Alejandra
A1 - Mazumdar, Tilottama
A1 - Jiang, Shixiong
A1 - Radek, Renate
A1 - Thiem, Julian N.
A1 - Feng, Linshan
A1 - Petrašiūnaitė, Vesta
A1 - Banasiak, Ronald
A1 - Golian, Marek
A1 - Gleske, Melanie
A1 - Christophe, Lucas
A1 - Springer, Andreas
A1 - Buellesbach, Jan
A1 - McMahon, Dino Peter
T1 - Defensive behavior is linked to altered surface chemistry following infection in a termite society
N2 - The care-kill response determines whether a sick individual will be treated or eliminated from an insect society, but little is known about the physiological underpinnings of this process. We exploited the stepwise infection dynamics of an entomopathogenic fungus in a termite to explore how care-kill transitions occur, and identify the chemical cues behind these shifts. We found collective responses towards pathogen-injected individuals to vary according to severity and timing of pathogen challenge, with elimination, via cannibalism, occurring sooner in response to a severe active infection. However, injection with inactivated fungal blastospores also resulted in increased albeit delayed cannibalism, even though it did not universally cause host death. This indicates that the decision to eliminate an individual is triggered before pathogen viability or terminal disease status has been established. We then compared the surface chemistry of differently challenged individuals, finding increased amounts of long-chained methyl-branched alkanes with similar branching patterns in individuals injected with both dead and viable fungal blastospores, with the latter showing the largest increase. This coincided with the highest amounts of observed cannibalism as well as signs of severe moribundity. Our study provides new mechanistic insight into the emergent collective behaviors involved in the disease defense of a termite society.
KW - Termite
KW - Social Immunity
KW - CHC
KW - Pathogen
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594468
DO - https://doi.org/10.1038/s41598-023-42947-9
SN - 2045-2322
VL - 13
IS - 1
SP - 1
EP - 16
PB - Macmillan Publishers Limited, part of Springer Nature
CY - London
AN - OPUS4-59446
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 - Fire Behavior of Pressure-sensitive Adhesive Tapes and Bonded Materials
N2 - Pressure-sensitive adhesive tapes are used in several industrial applications such as con-struction, railway vehicles and the automotive sector,where the burning behavior is ofcrucial importance. Flame retarded adhesivetapes are developed and provided, however,often without considering the interaction of adhesive tapes and the bonded materialsduring burning nor the contribution of the tapes to fire protection goal of the bondedcomponents in distinct fire tests. This publication delivers an empirical comprehensiveknowledge how adhesive tapes and their flame retardancy effect the burning behaviorof bonded materials. With a special focus on the interaction between the single compo-nents, one flame retarded tape and one tapewithout flame retardant are examined inscenarios of emerging and developing fires, along with their bonds with the commonmaterials wood, zinc-plated steel, mineral wool, polycarbonate, and polymethylmethacry-late. The flame retardant significantly improved the flame retardancy of the tape as afree-standing object and yielded a V-2 rating in UL 94 vertical test and raised the OxygenIndex by 5 vol.%. In bonds, or rather laminates, the investigations prove that the choiceof carrier and substrates are the factors with the greatest impact on the fire propertiesand can change the peak of heat release rate and the maximum average rate of heatemission up to 25%. This research yielded a good empirical overall understanding of thefire behavior of adhesive tapes and bonded materials. Thus, it serves as a guide for tapemanufacturers and applicants to develop tapes and bonds more substrate specific.
KW - Adhesives
KW - Cone calorimeter
KW - Flame retardancy
KW - Laminates
KW - Phosphorus flame retardants
KW - Pressure-sensitive adhesive
KW - Tapes
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593207
DO - https://doi.org/10.1002/fam.3171
SN - 0308-0501
SN - 1099-1018
VL - 48
IS - 1
SP - 114
EP - 127
PB - Wiley
CY - New York, NY
AN - OPUS4-59320
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Grundmann, Jana
A1 - Ermilova, Elena
A1 - Hertwig, Andreas
A1 - Klapetek, Petr
A1 - Pereira, Silvania F.
A1 - Rafighdoost, Jila
A1 - Bodermann, Bernd
T1 - Optical and Tactile Measurements on SiC Sample Defects
N2 - The different defect types on SiC samples are measured with various measurement methods including optical and tactile methods. The defect types investigated include particles, carrots and triangles and they are analyzed with imaging ellipsometry, coherent Fourier scatterometry and atomic force microscopy. Each of these methods measures different properties of the defects and they all together contribute to a complete analysis.
T2 - SMSI 2023 - Sensor and Measurement Science International
CY - Nuremberg, Germany
DA - 08.05.2023
KW - Defects
KW - Silicon carbide
KW - Imaging ellipsometry
KW - Atomic force microscopy
KW - Coherent Fourier scatterometry
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593397
SN - 978-3-9819376-8-8
DO - https://doi.org/10.5162/SMSI2023/D5.2
VL - 2023/D5
SP - 233
EP - 234
PB - AMA Service
CY - Wunstorf
AN - OPUS4-59339
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bayerlein, Bernd
A1 - Schilling, Markus
A1 - Birkholz, Henk
A1 - Jung, Matthias
A1 - Waitelonis, Jörg
A1 - Mädler, Lutz
A1 - Sack, Harald
T1 - PMD Core Ontology: Achieving semantic interoperability in materials science
N2 - Knowledge representation in the Materials Science and Engineering (MSE) domain is a vast and multi-faceted challenge: Overlap, ambiguity, and inconsistency in terminology are common. Invariant (consistent) and variant (context-specific) knowledge are difficult to align cross-domain. Generic top-level semantic terminology often is too abstract, while MSE domain terminology often is too specific. In this paper, an approach how to maintain a comprehensive MSE-centric terminology composing a mid-level ontology–the Platform MaterialDigital Core Ontology (PMDco)–via MSE community-based curation procedures is presented. The illustrated findings show how the PMDco bridges semantic gaps between high-level, MSE-specific, and other science domain semantics. Additionally, it demonstrates how the PMDco lowers development and integration thresholds. Moreover, the research highlights how to fuel it with real-world data sources ranging from manually conducted experiments and simulations with continuously automated industrial applications.
KW - Ontology
KW - Materials science and engineering
KW - Knowledge representation
KW - Reproducibility
KW - Semantic interoperability
KW - Semantic data integration
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-592948
DO - https://doi.org/10.1016/j.matdes.2023.112603
SN - 0264-1275
VL - 237
SP - 1
EP - 12
PB - Elsevier
CY - Amsterdam
AN - OPUS4-59294
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gottinger, A.
A1 - Ladu, Luana
A1 - Blind, K.
T1 - Standardization in the context of science and regulation: An analysis of the Bioeconomy
N2 - Standards play a crucial role in the transition to more sustainable production and consumption models by promoting the development of new markets for innovative products. In the case of the bioeconomy, standards are particularly relevant to ensure the sustainability of products and processes. Hence, standards represent an essential strategic tool to foster sustainable development. Furthermore, the standard-setting process brings together different stakeholders, which encourages research and the transfer of knowledge to industrial practice. In particular, scientific publications assist the standardisation process by providing scientific evidence. This study investigates the role of science and regulation in the bioeconomy standardisation process. It first provides a general analysis of bioeconomy-related standards, followed by an analysis of the regulations and publications referenced in the standards. Our analysis discloses a strong use of scientific knowledge in the bioeconomy standardisation process and demonstrates the readiness to integrate novel academic findings into revised versions of the standards. In addition, it reveals that the interaction between science and regulation is an important driver for standardisation activities around the bioeconomy, needed to support sustainable transitions.
KW - Bioeconomy
KW - Standardisation
KW - Knowledge Use
KW - Socio-technical Transition
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599899
DO - https://doi.org/10.1016/j.envsci.2023.06.013
VL - 147
SP - 188
EP - 200
PB - Elsevier
AN - OPUS4-59989
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Jablonka, Kevin Maik
A1 - Ai, Qianxiang
A1 - Al-Feghali, Alexander
A1 - Badhwar, Shruti
A1 - Bocarsly, Joshua D.
A1 - Bran, Andres M.
A1 - Bringuier, Stefan
A1 - Brinson, L. Catherine
A1 - Choudhary, Kamal
A1 - Circi, Defne
A1 - Cox, Sam
A1 - de Jong, Wibe A.
A1 - Evans, Matthew L.
A1 - Gastellu, Nicolas
A1 - Genzling, Jerome
A1 - Gil, María Victoria
A1 - Gupta, Ankur K.
A1 - Hong, Zhi
A1 - Imran, Alishba
A1 - Kruschwitz, Sabine
A1 - Labarre, Anne
A1 - Lála, Jakub
A1 - Liu, Tao
A1 - Ma, Steven
A1 - Majumdar, Sauradeep
A1 - Merz, Garrett W.
A1 - Moitessier, Nicolas
A1 - Moubarak, Elias
A1 - Mouriño, Beatriz
A1 - Pelkie, Brenden
A1 - Pieler, Michael
A1 - Ramos, Mayk Caldas
A1 - Ranković, Bojana
A1 - Rodriques, Samuel G.
A1 - Sanders, Jacob N.
A1 - Schwaller, Philippe
A1 - Schwarting, Marcus
A1 - Shi, Jiale
A1 - Smit, Berend
A1 - Smith, Ben E.
A1 - Van Herck, Joren
A1 - Völker, Christoph
A1 - Ward, Logan
A1 - Warren, Sean
A1 - Weiser, Benjamin
A1 - Zhang, Sylvester
A1 - Zhang, Xiaoqi
A1 - Zia, Ghezal Ahmad Jan
A1 - Scourtas, Aristana
A1 - Schmidt, K. J.
A1 - Foster, Ian
A1 - White, Andrew D.
A1 - Blaiszik, Ben
T1 - 14 examples of how LLMs can transform materials science and chemistry: a reflection on a large language model hackathon
N2 - Large-language models (LLMs) such as GPT-4 caught the interest of many scientists. Recent studies suggested that these models could be useful in chemistry and materials science. To explore these possibilities, we organized a hackathon. This article chronicles the projects built as part of this hackathon. Participants employed LLMs for various applications, including predicting properties of molecules and materials, designing novel interfaces for tools, extracting knowledge from unstructured data, and developing new educational applications. The diverse topics and the fact that working prototypes could be generated in less than two days highlight that LLMs will profoundly impact the future of our fields. The rich collection of ideas and projects also indicates that the applications of LLMs are not limited to materials science and chemistry but offer potential benefits to a wide range of scientific disciplines.
KW - Large Language model
KW - Hackathon
KW - Concrete
KW - Prediction
KW - Inverse Design
KW - Orchestration
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589961
DO - https://doi.org/10.1039/d3dd00113j
VL - 2
IS - 5
SP - 1233
EP - 1250
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58996
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Moreno Torres, Benjami
A1 - Völker, Christoph
A1 - Firdous, Rafia
T1 - Concreting a sustainable future: A dataset of alkali-activated concrete and its properties
N2 - This data article introduces a dataset comprising 1630 alkali-activated concrete (AAC) mixes, compiled from 106 literature sources. The dataset underwent extensive curation to address feature redundancy, transcription errors, and duplicate data, yielding refined data ready for further data-driven science in the field of AAC, where this effort constitutes a novelty. The carbon footprint associated with each material used in the AAC mixes, as well as the corresponding CO2 footprint of every mix, were approximated using two published articles. Serving as a foundation for future expansions and rigorous data applications, this dataset enables the characterization of AAC properties through machine learning algorithms or as a benchmark for performance comparison among different formulations. In summary, the dataset provides a resource for researchers focusing on AAC and related materials and offers insights into the environmental benefits of substituting traditional Portland concrete with AAC.
KW - Multidisciplinary
KW - Data Set
KW - Alkali Activated Concrete
KW - Data driven design
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589974
DO - https://doi.org/10.1016/j.dib.2023.109525
SN - 2352-3409
VL - 50
SP - 1
EP - 9
PB - Elsevier B.V.
AN - OPUS4-58997
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Völker, Christoph
A1 - Moreno Torres, Benjami
A1 - Zia, Ghezal Ahmad Jan
A1 - Rug, Tehseen
A1 - Firdous, Rafia
A1 - Böhmer, Felix
A1 - Stephan, Dietmar
A1 - Kruschwitz, Sabine
T1 - Presenting SLAMD – A Sequential Learning Based Software for the Inverse Design of Sustainable Cementitious Materials
N2 - In recent decades, the number of components in concrete has grown, particularly in formulations aimed at reducing carbon footprints. Innovations include diverse binders, supplementary cementitious materials, activators, concrete admixtures, and recycled aggregates. These developments target not only the enhancement of material properties but also the mitigation of the ecological and economic impacts of concrete — the most extensively used material by humankind. However, these advancements also introduce a greater variability in the composition of raw materials. The material’s behavior is significantly influenced by its nanoscale properties, which can pose challenges in accurate characterization. Consequently, there’s an increasing need for experimental tuning of formulations. This is accompanied by a more inconsistent composition of raw materials, which makes an experimental tuning of formulations more and more necessary. However, the increased complexity in composition presents a challenge in finding the ideal formulation through trial and error. Inverse design (ID) techniques offer a solution to this challenge by allowing for a comprehensive search of the entire design space to create new and improved concrete formulations. In this publication, we introduce the concept of ID and demonstrate how our open-source app “SLAMD” provides all necessary steps of the workflow to adapt it in the laboratory, lowering the application barriers. The intelligent screening process, guided by a predictive model, leads to a more efficient and effective data-driven material design process resulting in reduced carbon footprint and improved material quality while considering socio-economic factors in the materials design.
KW - Sustainable concrete
KW - Machine learning optimization
KW - Inverse design techniques
KW - Scientific software
KW - Data-driven material design
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589993
DO - https://doi.org/10.17756/nwj.2023-s2-032
VL - 9
SP - 180
EP - 187
AN - OPUS4-58999
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gehrenkemper, Lennart
A1 - Rühl, Isabel
A1 - Westphalen, Tanja
A1 - Simon, Fabian
A1 - von der Au, Marcus
A1 - Cossmer, Antje
A1 - Meermann, Björn
T1 - Investigating the uptake and fate of per- and polyfluoroalkylated substances (PFAS) in bean plants (Phaseolus vulgaris): comparison between target MS and sum parameter analysis via HR-CS-GFMAS
N2 - AbstractIn this study, we present a screening method based on molecular absorption spectrometry to study PFAS uptake and fate in plants. To evaluate the suitability of this method we analyzed plant extracts with molecular absorption spectrometry (MAS) as well as liquid chromatography–tandem mass spectrometry (LC–MS/MS) for mass balance studies (w(F)). French bean plants (Phaseolus vulgaris) were grown on soil spiked using eight PFAS substances that vary in chain length and functional group composition. Specifically, these include three short-chained (C4–C5), five long-chained (C7–C10) carboxylic acids, one sulfonic acid and one sulfonic amide moieties. To investigate substance-specific PFAS uptake systematically, PFAS were spiked as single substance spike. Additionally, we studied one mixture of the investigated substances in equal proportions regarding w(F) and four PFAS mixtures of unknown composition. After 6 weeks, the plants were separated into four compartments. We analyzed the four compartments as well as the soil for extractable organically bound fluorine (EOF) by high resolution-continuum source-graphite furnace-molecular absorption spectrometry (HR-CS-GFMAS) as well as for sum of ten target-PFAS by LC–MS/MS. All three short-chained PFAS perfluorobutanoic acid (PFBA), perfluorobutanoic sulfonic acid (PFBS) and perfluoropentanoic acid (PFPeA) were determined in high concentrations mainly in the fruits of the investigated plants while long-chained PFAS perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) were mainly determined in roots. PFBS was determined in remarkably high concentrations in leaves compartment by both quantification methods. Overall, comprehensive results of single substance spikes were in good agreement for both methods except for a few cases. Hence, two phenomena were identified: for mixed PFAS spikes of unknown composition huge differences between EOF and sum of target PFAS were observed with systematically higher EOF values. Overall, both methods indicate comparable results with MS being more reliable for known PFAS contamination and MAS being more valuable to identify PFAS exposure of unknown composition.
Graphical Abstract
KW - Pollution
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589394
DO - https://doi.org/10.1186/s12302-023-00811-7
VL - 35
IS - 104
SP - 1
EP - 13
PB - Springer Science and Business Media LLC
AN - OPUS4-58939
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rieger, Philip
A1 - Magnall, Joseph M.
A1 - Gleeson, Sarah A.
A1 - Oelze, Marcus
T1 - Pyrite chemistry records a multistage ore forming system at the Proterozoic George Fisher massive sulfide Zn-Pb-Ag deposit, Mount Isa, Australia
N2 - Trace element (TE) analysis of pyrite via LA-ICP-MS can be used to reconstruct the conditions of pyrite formation in complex mineral systems. The Carpentaria province in northern Australia is host to some of the world’s highest value Zn-Pb (+Ag, Cu) deposits. The genesis of many of these deposits is controversial, with competing models of single-vs. multi-stage ore formation. In this study, LA-ICP-MS data of paragenetically constrained pyrite from the George Fisher Zn-Pb-Ag deposit has been analysed to investigate the chemistry of different stages of ore formation. Pyrite from correlative unmineralized host rocks has also been analysed to investigate evidence of distal hydrothermal anomalism. All LA-ICP-MS data have been statistically evaluated (principal component analysis) and interpreted together with whole rock lithogeochemical data of the same samples. Pre-ore diagenetic pyrite is compositionally similar to other Proterozoic diagenetic pyrite, with some evidence of minor hydrothermal anomalism that with further analysis could help define distal alteration. Pyrite from the different ore stages are compositionally distinct, consistent with a multi-stage system. Ore stage 1 pyrite exceeds background contents of Co, Cu, Zn, As, Ag, Sb, Tl, and Pb and has elevated Co/Ni ratios, whereas only Ni and Co are above background abundances in ore stage 2 and 3 pyrite, of which only ore stage 3 pyrite has high Co/Ni ratios. Ore stage 1 pyrite has a similar composition to hydrothermal pyrite in the undeformed northern Carpentaria CD-type deposits and was likely syn-diagenesis. Ore stage 2 was syn-deformation, and resulted in replacement and recrystallization of pre-existing pyrite, and the expulsion of incompatible TEs. Ore stage 3 formed via a later Cu-Zn-Pb mineralizing event that resulted in a new geochemically distinct generation of Co-rich pyrite. Overall, this study demonstrates the value of paragenetically-constrained pyrite TE data for refining genetic models in complex sediment hosted mineral systems.
KW - General Earth and Planetary Sciences
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590407
DO - https://doi.org/10.3389/feart.2023.892759
VL - 11
SP - 1
EP - 19
PB - Frontiers Media SA
AN - OPUS4-59040
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Inostroza, Manuel
A1 - Fernandez, Bárbara
A1 - Aguilera, Felipe
A1 - Layana, Susana
A1 - Walter, Thomas R.
A1 - Zimmer, Martin
A1 - Rodríguez-Díaz, Augusto
A1 - Oelze, Marcus
T1 - Physical and chemical characteristics of active sulfur flows observed at Lastarria volcano (northern Chile) in January 2019
N2 - Molten sulfur is found in various subaerial volcanoes. However, limited records of the pools and flows of molten sulfur have been reported: therefore, questions remain regarding the physicochemical processes behind this phenomenon. A suite of new sulfur flows, some of which active, was identified at the Lastarria volcano (northern Chile) and studied using satellite imagery, in situ probing, and temperature and video recording. This finding provides a unique opportunity to better understand the emplacement mechanisms and mineral and chemical compositions of molten sulfur, in addition to gaining insight into its origin. Molten sulfur presented temperatures of 124–158°C, with the most prolonged sulfur flow reaching 12 m from the source. Photogrammetric tools permitted the identification of levees and channel structures, with an estimated average flow speed of 0.069 m/s. Field measurements yielded a total volume of 1.45 ± 0.29 m3 of sulfur (equivalent to ∼2.07 tons) mobilized during the January 2019 event for at least 408 min. Solidified sulfur was composed of native sulfur with minor galena and arsenic- and iodine-bearing minerals. Trace element analysis indicated substantial enrichment of Bi, Sb, Sn, Cd, as well as a very high concentration of As (>40.000 ppm). The January 2019 molten sulfur manifestations in Lastarria appear to be more enriched in As compared to the worldwide known volcanoes with molten sulfur records, such as the Shiretoko-Iozan and Poás volcanoes. Furthermore, their rheological properties suggest that the “time of activity” in events such as this could be underestimated as flows in Lastarria have moved significantly slower than previously thought. The origin of molten sulfur is ascribed to the favorable S-rich chemistry of fumarolic gases and changes in host rock permeability (fracture opening). Molten sulfur in Lastarria correlates with a peak in activity characterized by high emissions of SO2 and other acid species, such as HF and HCl, in addition to ground deformation. Consequently, molten sulfur was framed within a period of volcanic unrest in Lastarria, triggered by changes in the magmatic-hydrothermal system. The appearance of molten sulfur is related to physicochemical perturbations inside the volcanic system and is perhaps a precursor of eruptive activity, as observed in the Poás and Turrialba volcanoes.
KW - General Earth and Planetary Sciences
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590331
DO - https://doi.org/10.3389/feart.2023.1197363
VL - 11
SP - 1
EP - 18
PB - Frontiers Media SA
AN - OPUS4-59033
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Klewe, Tim
A1 - Völker, Tobias
A1 - Landmann, Mirko
A1 - Kruschwitz, Sabine
T1 - LIBS‐ConSort: Development of a sensor‐based sorting method for construction and demolition waste
N2 - AbstractA joint project of partners from industry and research institutions approaches the challenge of construction and demolition waste (CDW) sorting by investigating and testing the combination of laser‐induced breakdown spectroscopy (LIBS) with near‐infrared (NIR) spectroscopy and visual imaging. Joint processing of information (data fusion) is expected to significantly improve the sorting quality of various materials like concrete, main masonry building materials, organic components, etc., and may enable the detection and separation of impurities such as SO3‐cotaining building materials (gypsum, aerated concrete, etc.)Focusing on Berlin as an example, the entire value chain will be analyzed to minimize economic / technological barriers and obstacles at the cluster level and to sustainably increase recovery and recycling rates.The objective of this paper is to present current progress and results of the test stand development combining LIBS with NIR spectroscopy and visual imaging. In the future, this laboratory prototype will serve as a fully automated measurement setup to allow real‐time classification of CDW on a conveyor belt.
T2 - 21st Ibausil - International Conference on Building Materials
CY - Weimar, Germany
DA - 13.09.2023
KW - NDT
KW - Material cassification
KW - Recycling
KW - LIBS
KW - Data fusion
KW - Construction and demolition waste
KW - Circular economy
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590734
DO - https://doi.org/10.1002/cepa.2866
SN - 2509-7075
VL - 6
IS - 6
SP - 973
EP - 976
PB - Ernst & Sohn GmbH
AN - OPUS4-59073
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Charmi, Amir
A1 - Mustapha, Samir
A1 - Yilmaz, Bengisu
A1 - Heimann, Jan
A1 - Prager, Jens
T1 - A Machine Learning Based-Guided Wave Approach for Damage Detection and Assessment in Composite Overwrapped Pressure Vessels
N2 - The applications of composite overwrapped pressure vessels (COPVs) in extreme conditions, such as storing hydrogen gases at very high pressure, impose new requirements related to the system's integrity and safety. The development of a structural health monitoring (SHM) system that allows for continuous monitoring of the COPVs provides rich information about the structural integrity of the component. Furthermore, the collected data can be used for different purposes such as increasing the periodic inspection intervals, providing a remaining lifetime prognosis, and also ensuring optimal operating conditions. Ultimately this information can be complementary to the development of the envisioned digital twin of the monitored COPVs. Guided waves (GWs) are preferred to be used in continuous SHM given their ability to travel in complex structures for long distances. However, obtained GW signals are complex and require advanced processing techniques. Machine learning (ML) is increasingly utilized as the main part of the processing pipeline to automatically detect anomalies in the system's integrity. Hence, in this study, we are scrutinizing the potential of using ML to provide continuous monitoring of COPVs based on ultrasonic GW data. Data is collected from a network of sensors consisting of fifteen Piezoelectric (PZT) wafers that were surface mounted on the COPV. Two ML algorithms are used in the automated evaluation procedure (i) a long short-term memory (LSTM) autoencoder for anomaly detection (defects/impact), and (ii) a convolutional neural network (CNN) model for feature extraction and classification of the artificial damage sizes and locations. Additional data augmentation steps are introduced such as modification and addition of random noise to original signals to enhance the model's robustness to uncertainties. Overall, it was shown that the ML algorithms used were able to detect and classify the simulated damage with high accuracy.
T2 - 13th European Conference on Non-Destructive Testing (ECNDT) 2023
CY - Lisbon, Portugal
DA - 03.07.2023
KW - Machine learning
KW - Structural health monitoring
KW - COPV
KW - Guided waves
KW - Damage localization
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590789
DO - https://doi.org/10.58286/28079
SN - 2941-4989
VL - 1
IS - 1
SP - 1
EP - 6
PB - NDT.net
CY - Mayen
AN - OPUS4-59078
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mustapha, S.
A1 - Yilmaz, Bengisu
A1 - Heimann, Jan
A1 - Brence, Blaz
A1 - Prager, Jens
T1 - Guided Waves Propagation in Composite Overwrapped Pressure Vessel
N2 - The application of composite overwrapped pressure vessels (COPV) to store hydrogen and other compressed gases, especially when operating at high pressures, imposed the need for an innovative and reliable approach to ensure the safe operation of the system. Continuous structural health monitoring (SHM) based on ultrasonic guided waves (GWs) is a promising approach due to the ability of the wave to propagate for long distances and go around complex structures, moreover the high sensitivity to various failure modes such as delamination, matrix cracking and debonding. In this study, we scrutinize the behavior of (GWs) within the COPV using a network of PZT elements that are used for excitation and sensing. A laser doppler vibrometer (LDV) was also used to scan the surface of the vessel in various directions. L(0,1) and L(0,2) were observed in the captured signal. The L(0, 2) appeared to be a dominant mode in the COPV and was capable of propagating along the entire length and maintaining a good signal-to-noise ratio. The L(0,2) mode maintained the same phase velocity when it is captured at various excitation angles (0, 45, and 90 degrees). The reduced effect of the orthotropy of the materials on the propagating waves is an important result as it will reduce the complexity in data processing when performing damage identification.
T2 - 13th. European Conference on Non-Destructive Testing (ECNDT)
CY - Lisbon, Portugal
DA - 03.07.2023
KW - Composite Overwrapped Pressure Vessels
KW - Guided Waves
KW - Laser Doppler Vibrometer
KW - Structural Health Monitoring
KW - Sensors Placement
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591081
DO - https://doi.org/10.58286/28068
SN - 2941-4989
VL - 1
IS - 1
SP - 1
EP - 6
PB - NDT.net
CY - Mayen
AN - OPUS4-59108
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Yilmaz, Bengisu
A1 - Heimann, Jan
A1 - Mustapha, S.
A1 - Charmi, Amir
A1 - Prager, Jens
T1 - Guided wave ultrasonic feature determination in Type IV composite overwrapped pressure vessels towards the digital twin
N2 - The digitalization of quality control processes and the underlying data infrastructures for safety relevant components, such as hydrogen pressure vessels, plays a significant role in the transition towards Industry 4.0. In the current safety regulations for hydrogen pressure vessels, there is no established concept for structural health monitoring. The development of a reliable structural health monitoring methodology for monitoring the structural integrity of pressure vessels enables a fast-forward transition from personnel- and costintensive recurring inspections, a.k.a. periodic maintenance, to predictive maintenance. In the work presented; we investigated the application of ultrasonic guided wave propagation to monitor and assess the condition of Type IV composite overwrapped pressure vessel (COPV). A sensor network of fifteen piezo-electric wafers is placed on the carbon fibre reinforced composite cylinder. Five different artificial damage configurations are created by gluing two different weight blocks on three different locations. The database containing measured guided wave data sets is enriched by two different boundary conditions. We utilized an open-source software, openBIS labnotebook, to store and analyse experimental datasets. The guided wave ultrasonic signals were investigated and analysed by using commonly used ultrasonic features (e.g., amplitude, frequency, time of flight) as well as non-traditional time-series features (kurtosis, skewness, variance). The features were used to calculate damage index and the detection performance for the results has been evaluated. The results suggest that both traditional and non-traditional features assume significant importance in artificial damage detection. The future works will additionally involve the impacts of operational conditions, such as periodic pressure variations temperature loadings as well as material degradations.
T2 - 13th European Conference on Non-Destructive Testing (ECNDT)
CY - Lisbon, Portugal
DA - 03.07.2023
KW - Industry 4.0
KW - Composite overwrapped pressure vessels
KW - Structural health monitoring
KW - Ultrasonic guided waves
KW - Predictive maintenance
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-591094
DO - https://doi.org/10.58286/28072
SN - 2941-4989
VL - 1
IS - 1
SP - 1
EP - 6
PB - NDT.net
CY - Mayen
AN - OPUS4-59109
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scheurrell, Kerstin
A1 - B. Martins, Inês C.
A1 - Murray, Claire
A1 - Emmerling, Franziska
T1 - Exploring the role of solvent polarity in mechanochemical Knoevenagel condensation: in situ investigation and isolation of reaction intermediates
N2 - Mechanochemistry has proven to be a highly effective method for the synthesis of organic compounds. We studied the kinetics of the catalyst-free Knoevenagel reaction between 4-nitrobenzaldehyde and malononitrile, activated and driven by ball milling. The reaction was investigated in the absence of solvents (neat grinding) and in the presence of solvents with different polarities (liquid-assisted grinding). The reaction was monitored using time-resolved in situ Raman spectroscopy and powder X-ray diffraction (PXRD). Our results indicate a direct relationship between solvent polarity and reaction kinetics, with higher solvent polarity leading to faster product (2-(4-nitrobenzylidone)malononitrile) formation. For the first time, we were able to isolate and determine the structure of an intermediate 2-(hydroxy(4-nitrophenyl)methyl)malononitrile based on PXRD data.
KW - Physical and Theoretical Chemistry
KW - General Physics and Astronomy
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-588071
DO - https://doi.org/10.1039/D3CP02883F
SN - 1463-9076
VL - 25
IS - 35
SP - 23637
EP - 23644
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-58807
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Protasov, E
A1 - Noah, J O
A1 - Kästle Silva, J O
A1 - Mies, U S
A1 - Hervé, V
A1 - Dietrich, C
A1 - Lang, K
A1 - Mikulski, L
A1 - Platt, K
A1 - Poehlein, A
A1 - Köhler-Ramm, T
A1 - Miambi, E
A1 - Boga, H I
A1 - Feldewert, C
A1 - Ngugi, G K
A1 - Plarre, Rüdiger
A1 - Sillam-Dussès, D
A1 - Šobotník, J
A1 - Daniel, R
A1 - Brune, A
T1 - Diversity and taxonomic revision of methanogens and other archaea in the intestinal tract of terrestrial arthropods
N2 - Methane emission by terrestrial invertebrates is restricted to millipedes, termites, cockroaches, and scarab beetles. The arthropod-associated archaea known to date belong to the orders Methanobacteriales, Methanomassiliicoccales, Methanomicrobiales, and Methanosarcinales, and in a few cases also to nonmethanogenic Nitrososphaerales and Bathyarchaeales. However, all major host groups are severely undersampled, and the taxonomy of existing lineages is not well developed. Full-length 16S rRNA gene sequences and genomes of arthropod-associated archaea are scarce, reference databases lack resolution, and the names of many taxa are either not validly published or under-classified and require revision. Here, we investigated the diversity of archaea in a wide range of methane-emitting arthropods, combining phylogenomic analysis of isolates and metagenome-assembled genomes (MAGs) with amplicon sequencing of full-length 16S rRNA genes. Our results allowed us to describe numerous new species in hitherto undescribed taxa among the orders Methanobacteriales (Methanacia, Methanarmilla, Methanobaculum, Methanobinarius, Methanocatella, Methanoflexus, Methanorudis, and Methanovirga, all gen. nova), Methanomicrobiales (Methanofilum and Methanorbis, both gen. nova), Methanosarcinales (Methanofrustulum and Methanolapillus, both gen. nova), Methanomassiliicoccales (Methanomethylophilaceae fam. nov., Methanarcanum, Methanogranum, Methanomethylophilus, Methanomicula, Methanoplasma, Methanoprimaticola, all gen. nova), and the new family Bathycorpusculaceae (Bathycorpusculum gen. nov.). Reclassification of amplicon libraries from this and previous studies using this new taxonomic framework revealed that arthropods harbor only CO2 and methyl-reducing hydrogenotrophic methanogens.
Numerous genus-level lineages appear to be present exclusively in arthropods,suggesting long evolutionary trajectories with their termite, cockroach, and millipede hosts, and a radiation into various microhabitats and ecological nichesprovided by their digestive tracts (e.g., hindgut compartments, gut wall, or anaerobic protists). The distribution patterns among the different host groups are often complex, indicating a mixed mode of transmission and a parallel evolution of invertebrate and vertebrate-associated lineages.
KW - Nitrososphaerales
KW - Archaea
KW - Methanogens
KW - Gut microbiota
KW - Termites
KW - Cockroaches
KW - Millipedes
KW - Bathyarchaeia
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-588230
DO - https://doi.org/10.3389/fmicb.2023.1281628
SN - 1664-302X
VL - 14
SP - 1
EP - 21
PB - Frontiers
AN - OPUS4-58823
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ruyle, B.
A1 - Pickard, H.
A1 - Schultes, L.
A1 - Fredriksson, F.
A1 - Heffernan, A.
A1 - Knappe, D.
A1 - Lord, H.
A1 - Meng, P.
A1 - Mills, M.
A1 - Ndungu, K.
A1 - Roesch, Philipp
A1 - Rundberget, J.T.
A1 - Tettenhorst, D.
A1 - Van Buren, J.
A1 - Vogel, Christian
A1 - Westerman, D.
A1 - Yeung, L.
A1 - Sunderland, E.
T1 - Interlaboratory Comparison of Extractable Organofluorine Measurements in Groundwater and Eel (Anguilla rostrata): Recommendations for Methods Standardization
N2 - Research on per- and polyfluoroalkyl substances (PFAS) frequently incorporates organofluorine measurements, particularly because they could support a class-based approach to regulation. However, standardized methods for organofluorine analysis in a broad suite of matrices are currently unavailable, including a method for extractable organofluorine (EOF) measured using combustion ion chromatography (CIC). Here, we report the results of an international interlaboratory comparison. Seven laboratories representing academia, government, and the private sector measured paired EOF and PFAS concentrations in groundwater and eel (Anguilla rostrata) from a site contaminated by aqueous film-forming foam. Among all laboratories, targeted PFAS could not explain all EOF in groundwater but accounted for most EOF in eel. EOF results from all laboratories for at least one replicate extract fell within one standard deviation of the interlaboratory mean for groundwater and five out of seven laboratories for eel. PFAS spike mixture recoveries for EOF measurements in groundwater and eel were close to the criterion (±30%) for standardized targeted PFAS methods. Instrumental operation of the CIC such as replicate sample injections was a major source of measurement uncertainty. Blank contamination and incomplete inorganic fluorine removal may introduce additional uncertainties. To elucidate the presence of unknown organofluorine using paired EOF and PFAS measurements, we recommend that analysts carefully consider confounding methodological uncertainties such as differences in precision between measurements, data processing steps such as blank subtraction and replicate analyses, and the relative recoveries of PFAS and other fluorine compounds.
KW - Extractable organic fluorine
KW - Per- and Polyfluoroalkyl substances (PFAS)
KW - Combustion ion chromatography (CIC)
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-587726
DO - https://doi.org/10.1021/acs.est.3c04560
SN - 0013-936X
VL - 57
IS - 48
SP - 20159
EP - 20168
PB - American Chemical Society (ACS)
AN - OPUS4-58772
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Turski Silva Diniz, Analice
A1 - Marti, J. M.
A1 - Schartel, Bernhard
T1 - High Heat Resistance Can Be Deceiving: Dripping Behavior of Polyamide 4.6 in Fire
N2 - Polyamide 4.6 (PA46) is a high-heat-resistant polymer, but it has no dripping resistance under fire. Three commercial grades of PA46 are investigated under UL 94 vertical fire test conditions. Their performances are discussed based on the materials’ structural, thermal, and rheological properties. PA46 presents flaming drops, whereas dripping is prevented in the flame-retarded PA46.
Friction-modified PA46 has increased flaming dripping. Temperature profiles of the specimens under fire and the temperature of the drops are measured by thermocouples. A UL 94 vertical test configuration consisting of two flame applications is designed to assess the quantitative dripping behavior of the set of materials by the particle finite element method (PFEM). Polymer properties (activation energy and Arrhenius coefficient of decomposition, char yield, density, effective heat of combustion, heat of decomposition, specific heat capacity, and thermal conductivity) in addition to rheological responses in high temperatures are estimated and measured as input parameters for the simulations. The dripping behavior obtained by simulated materials corresponds with the experimental results in terms of time and drop size. A consistent picture of the interplay of the different phenomena controlling dripping under fire appears to deliver a better understanding of the role of different materials’ properties
KW - Dripping
KW - UL 94
KW - PFEM
KW - High heat resistance
KW - Polyamide 4.6
KW - Flammability
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-586015
DO - https://doi.org/10.1002/mame.202300091
SN - 1439-2054
SN - 1438-7492
VL - 308
IS - 10
SP - 1
EP - 11
PB - Wiley-VCH
AN - OPUS4-58601
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Meng, Xiangmeng
A1 - Putra, Stephen Nugraha
A1 - Bachmann, Marcel
A1 - Rethmier, Michael
T1 - Influence of the spatial laser energy absorption on the molten pool dynamics in high-power laser beam welding
N2 - The spatial laser energy absorption inside the keyhole is decisive for the dynamic molten pool behaviors and the resultant weld properties in high-power laser beam welding (LBW). In this paper, a numerical simulation of the LBW process, considering the 3D transient heat transfer, fluid flow, and keyhole dynamics, is implemented, in which the free surface is tracked by the volume-of-fluid algorithm. The underlying laser-material interactions, i.e., the multiple reflections and Fresnel absorption, are considered by an advanced ray-tracing method based on a localized level-set strategy and a temperature-dependent absorption coefficient. The laser energy absorption is analyzed from a time-averaged point of view for a better statistical representation. It is found for the first time that a significant drop in the time-averaged laser energy absorption occurs at the focus position of the laser beam and that the rest of the keyhole region has relatively homogeneous absorbed energy. This unique absorption pattern may lead to a certain keyhole instability and have a strong correlation with the detrimental bulging and narrowing phenomena in the molten pool. The influence of different focus positions of the laser beam on the keyhole dynamics and molten pool profile is also analyzed. The obtained numerical results are compared with experimental measurements to ensure the validity of the proposed model.
KW - Laser beam welding
KW - Laser energy absorption
KW - Molten pool
KW - Keyhole dynamics
KW - Numerical modeling
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-587531
DO - https://doi.org/10.2351/7.0001078
SN - 1042-346X
VL - 35
IS - 4
SP - 1
EP - 8
PB - AIP Publishing
AN - OPUS4-58753
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chaudhuri, Somsubhro
A1 - Stamm, Michael
A1 - Krankenhagen, Rainer
T1 - Weather-dependent passive thermography and thermal simulation of in-service wind turbine blades
N2 - . To cope with the increase in the manufacturing and operation of wind turbines, wind farm operators need inspection tools that are able to provide reliable information while keeping the downtime low. Current inspection techniques require to stop the wind turbine. This work presents the current progress in the project EvalTherm, in which passive thermography is evaluated as a possible non-destructive inspection tool for operational wind turbine blades (WTBs). A methodology to obtain thermal images of rotating WTBs has been established in this project. However, the quality of the results is heavily dependent on various aspects such as weather conditions, information on the inspected WTB, damage history, etc. In this work, a section of a used WTB is simulated using finite-element modelling (FEM) as well as experimentally tested for evaluating the accuracy of the model. Such a model will provide insight into the potential thermal response of a certain structure (with specific material properties) in given weather (boundary) conditions. The model is able to provide satisfactory predictions of the thermal response of the structure, as well as indicate what thermal contrast(s) result from artificial defects introduced in the structure.
T2 - WindEurope Annual Event 2023
CY - Copenhagen, Denmark
DA - 25.04.2023
KW - FEM
KW - Thermografie
KW - Wind turbine rotor blades
KW - Windenergie Anlage Rotorblätter
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582777
DO - https://doi.org/10.1088/1742-6596/2507/1/012025
VL - 2507
SP - 1
EP - 12
PB - IOP Publishing Ltd.
AN - OPUS4-58277
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Völker, Christoph
A1 - Moreno Torres, Benjami
A1 - Rug, Tehseen
A1 - Firdous, Rafia
A1 - Zia, Ghezal Ahmad Jan
A1 - Lüders, Stefan
A1 - Lisdero Scaffino, Horacio
A1 - Höpler, Michael
A1 - Böhmer, Felix
A1 - Pfaff, Matthias
A1 - Stephan, Dietmar
A1 - Kruschwitz, Sabine
T1 - Data driven design of alkali-activated concrete using sequential learning
N2 - This paper presents a novel approach for developing sustainable building materials through Sequential Learning. Data sets with a total of 1367 formulations of different types of alkali-activated building materials, including fly ash and blast furnace slag-based concrete and their respective compressive strength and CO2-footprint, were compiled from the literature to develop and evaluate this approach. Utilizing this data, a comprehensive computational study was undertaken to evaluate the efficacy of the proposed material design methodologies, simulating laboratory conditions reflective of real-world scenarios. The results indicate a significant reduction in development time and lower research costs enabled through predictions with machine learning. This work challenges common practices in data-driven materials development for building materials. Our results show, training data required for data-driven design may be much less than commonly suggested. Further, it is more important to establish a practical design framework than to choose more accurate models. This approach can be immediately implemented into practical applications and can be translated into significant advances in sustainable building materials development.
KW - Sustainable building materials
KW - Sequential learning
KW - Data-driven materials design
KW - Alkali-activated building materials
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584376
UR - https://www.sciencedirect.com/science/article/pii/S095965262302379X
DO - https://doi.org/10.1016/j.jclepro.2023.138221
SN - 0959-6526
SN - 1879-1786
VL - 418
SP - 1
EP - 13
PB - Elsevier
CY - Amsterdam
AN - OPUS4-58437
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pech May, Nelson Wilbur
A1 - Tabasco-Novelo, Carolina
A1 - Quintana, Patricia
A1 - Rodriguez-Gattorno, Geonel
A1 - Alvarado-Gil, Juan J.
T1 - Evidence of a Thermal Diffusivity Gap in Sintered Li–Co–Sb–O Solid Solutions
N2 - In this work, the thermal properties of ternary Li₃ₓCo₇₋₄ₓSb₂₊ₓO₁₂ solid solutions are studied for different concentrations in the range 0 ≤ x ≤ 0.7. Samples are elaborated at four different sintering temperatures: 1100, 1150, 1200 and 1250 °C. The effect of increasing the content of Li⁺ and Sb⁵⁺, accompanied by the reduction of Co²⁺, on the thermal properties is studied. It is shown that a thermal diffusivity gap, which is more pronounced for low values of x, can be triggered at a certain threshold sintering temperature (around 1150 °C in this study). This effect is explained by the increase of contact area between adjacent grains. Nevertheless, this effect is found to be less pronounced in the thermal conductivity. Moreover, a new framework for heat diffusion in solids is presented that establishes that both the heat flux and the thermal energy (or heat) satisfy a diffusion equation and therefore highlights the importance of thermal diffusivity in transient heat conduction phenomena.
KW - General Chemical Engineering
KW - General Chemistry
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-593248
DO - https://doi.org/10.1021/acsomega.2c07557
SN - 2470-1343
VL - 8
IS - 8
SP - 7808
EP - 7815
PB - American Chemical Society (ACS)
CY - Washington, DC
AN - OPUS4-59324
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bente, Klaas
A1 - Rus, J.
A1 - Mooshofer, H.
A1 - Gaal, Mate
A1 - Grosse, C.U.
T1 - Broadband air-coupled ultrasound emitter and receiver enable simultaneous measurement of thickness and speed of sound in solids
N2 - Air-coupled ultrasound sensors have advantages over contact ultrasound sensors when a sample should not become contaminated or influenced by the couplant or the measurement has to be a fast and automated inline process. Thereby, air-coupled transducers must emit high-energy pulses due to the low air-to-solid power transmission ratios (10−3 to 10−8). Currently used resonant transducers trade bandwidth—a prerequisite for material parameter analysis—against pulse energy. Here we show that a combination of a non-resonant ultrasound emitter and a non-resonant detector enables the generation and detection of pulses that are both high in amplitude (130 dB) and bandwidth (2 µs pulse width). We further show an initial application: the detection of reflections inside of a carbon fiber reinforced plastic plate with thicknesses between 1.7 mm and 10 mm. As the sensors work contact-free, the time of flight and the period of the in-plate reflections are independent parameters. Hence, a variation of ultrasound velocity is distinguishable from a variation of plate thickness and both properties are determined simultaneously. The sensor combination is likely to find numerous industrial applications necessitating high automation capacity and opens possibilities for air-coupled, single-side ultrasonic inspection.
KW - Thermoacoustic emitter
KW - Optical microphone
KW - Air-coupled ultrasound
KW - Local resonance
KW - Thickness measurement
KW - Thickness resonance
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569533
DO - https://doi.org/10.3390/s23031379
VL - 23
IS - 3
SP - 1379
PB - MDPI
AN - OPUS4-56953
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ghafafian, Carineh
A1 - Trappe, Volker
ED - Vassilopoulos, A. P.
ED - Michaud, V.
T1 - Fully-reversed fatigue behavior of scarf joint repairs for wind turbine blade shell applications
N2 - To enable a quick and cost-effective return to service for wind turbine blades, localized repairs can be executed by technicians in the field. Scarf repairs, shown to be highly efficient with a smooth load transition across angled joint walls and a restored aerodynamic profile, are the focus of this work. The failure mechanisms of these structures were examined under quasi-static tensile and fully-reversed cyclic loading. While the scarf ratio was held constant at 1:50, the repair layup was varied between large-to-small and small-to-large. The effect of the presence of resin pockets and the fiber orientation mismatch between parent and repair material on the restored strength of BIAX ±45° glass fiber reinforced polymer scarf joint structures was studied.
T2 - 20th European Conference on Composite Materials
CY - Lausanne, Switzerland
DA - 26.06.2022
KW - Fatigue
KW - Scarf repairs
KW - Glass fiber reinforced polymers
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569646
UR - https://infoscience.epfl.ch/record/298799
SN - 978-2-9701614-0-0
VL - Vol. 5 - Applications and structures
SP - 195
EP - 201
PB - Composite Construction Laboratory (CCLab)
CY - Lausanne
AN - OPUS4-56964
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Völker, Tobias
A1 - Gornushkin, Igor B.
T1 - Investigation of a method for the correction of self-absorption by Planck function in laser induced breakdown spectroscopy
N2 - The electron density and temperature of a laser-induced plasma can be determined from the width and intensity of the spectral lines, provided that the corresponding optical transitions are optically thin. However, the lines in laser induced plasma are often self-absorbed. One of the methods of correction of this effect is based on the use of the Planck function and an iterative numerical calculation of the plasma temperature. In this study, the method is further explored and its inherent errors and limitations are evaluated. For this, synthetic spectra are used that fully correspond to the assumed conditions of a homogeneous isothermal plasma at local thermodynamic equilibrium. Based on the error analysis, the advantages and disadvantages of the method are discussed in comparison with other methods of self-absorption correction.
KW - LIBS
KW - Self-absorption
KW - Planck function
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572677
DO - https://doi.org/10.1039/D2JA00352J
SN - 0267-9477
SP - 1
EP - 6
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-57267
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Cysne Barbosa, Ana Paula
A1 - Azevedo do Nascimento, Allana
A1 - Pavasarytė, Lina
A1 - Trappe, Volker
A1 - Melo, D.
T1 - Effect of addition of thermoplastic self-healing agent on fracture toughness of epoxy
N2 - Self-healing agents have the potential to restore mechanical properties and extend service life of composite materials. Thermoplastic healing agents have been extensively investigated for this purpose in epoxy matrix composites due to their strong adhesion to epoxy and their ability to fill in microcracks. One of the most
investigated thermoplastic additives for this purpose is poly(ethylene-co-methacrylic acid) (EMAA). Despite the ability of thermoplastic healing agents to restore mechanical properties, it is important to assess how the addition of thermoplastic healing agents affect properties of the original epoxy material. In this work, EMAA was added to epoxy resin and the effect of the additive on fracture toughness of epoxy was evaluated. Results indicate that although added in low concentrations, EMAA can affect fracture toughness.
T2 - 6th Brazilian Conference on Composite Materials
CY - Tiradentes, Minas Gerais, Brazil
DA - 14.08.2022
KW - Epoxy
KW - Self-healing
KW - Thermoplastic
KW - Fracture
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572707
SN - 978-65-00-49386-3
DO - https://doi.org/10.29327/566492
SN - 2316-1337
SP - 219
EP - 222
AN - OPUS4-57270
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Matamoros-Veloza, A.
A1 - Stawski, Tomasz
A1 - Vargas, S.
A1 - Neville, A.
T1 - Study of a Local Structure at the Interface between Corrosion Films and Carbon Steel Surface in Undersaturated CO2 Environments
N2 - Industries transporting CO2 gas-saturated fluids have infrastructures made of carbon steel. This is a good material with great mechanical properties but prone to corrosion and potential failure. Corrosion in sweet environments involves the formation of FeCO3 as a corrosion film, which is recognized to play a protective role under certain conditions. This work on the dissolution of corrosion films in sweet environments, under acidic and undersaturated conditions, demonstrates that the effects on the integrity of steel are far more significant than the damage observed on the surface of the corrosion film. Our results prove that dissolution of FeCO3 involved the presence of an amorphous phase, the intermediate formation of FeCl2 or FeCl+, and the presence of a phase with short distance atom–atom correlations. The amorphous phase was identified as a mixture of retained γ-Fe and Fe3C. Partially broken α-Fe and Fe3C structures were identified to prove the damage on the material, confirming the interface zone without evident damage on the corrosion film. Dissolution affected both the α-Fe and FeCO3, with the lattice [102̅] from the FeCO3 crystalline structure being the fastest to dissolve. The damage of steel at the molecular scale was evident at the macroscale with pit depths of up to 250 μm. The impact on the integrity of steel can be, therefore, more drastic than frequently reported in industrial operations of CO2 transport industries that use cleaning procedures (e.g., acid treatment, pigging) as part of their operational activities.
KW - Steel
KW - Corrosion
KW - Siderite
KW - Diffraction
KW - Pair distribution function
KW - Synchrotron
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572156
DO - https://doi.org/10.1021/acsomega.2c07631
SN - 2470-1343
VL - 8
IS - 9
SP - 8497
EP - 8504
PB - ACS
AN - OPUS4-57215
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bui, M.
A1 - Hoffmann, K. F.
A1 - Braun, T.
A1 - Riedel, S.
A1 - Heinekamp, Christian
A1 - Scheurell, K.
A1 - Scholz, G.
A1 - Stawski, Tomasz
A1 - Emmerling, Franziska
T1 - An Amorphous Teflate Doped Aluminium Chlorofluoride:
A Solid Lewis-Superacid for the Dehydrofluorination of
Fluoroalkanes
N2 - Ananion-dopedaluminiumchlorofluoride AlCl0.1F2.8(OTeF5)0.1(ACF-teflate) was synthesized.The material contains pentafluor-oorthotellurate(teflate)groups, which mimic fluoride ions electronically, but are sterically more demanding. They are embedded into the amorphous structure. The latter was studied by PDF analysis, EXAFS data and MAS NMR spectroscopy. The mesoporous powder is a Lewis superacid, and ATR-IR spectra of adsorbed CD3CN reveal a blue-shift of the adsorption band by73 cm-1, which is larger than the shift for SbF5. Remarkably,ACF-teflate catalyzes dehydrofluorination reactions of mono-fluoroalkanes to yield olefins in C6D6. In these cases,no Friedel-Crafts products were formed.
KW - Aluminium fluorides
KW - Aluminium teflates
KW - C-F bond activation
KW - Lewis superacids
KW - Silanes
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572290
DO - https://doi.org/10.1002/cctc.202300350
SN - 1867-3880
SP - 1
EP - 7
PB - Wiley VHC-Verlag
AN - OPUS4-57229
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Trappe, Volker
A1 - Sachs, Patrick
ED - Vassilopoulos, A. P.
ED - Michaud, V.
T1 - Dynamic mechanical analysis of epoxy-matrix cross linking measured in-situ using an elastomer container
N2 - A new patented dynamic mechanical analysis (DMA) is presented, where the tensile, bending- or torsional stiffness of a media can be characterized in-situ during the phase transition from liquid to solid. An epoxy system, e.g. Hexion L285/H287, is filled into an elastomer container, such as a silicone tube. This can be mounted into a conventional OMA and, based on a linear viscoelastic approach, the storage modulus (E';G'), the loss modulus (E'';G'') and the loss angle tan(δ) can be measured at constant temperature as a function of time in order to investigate the liquid to sol-gel to solid transition. With this new method, the stiffness increase as a result of the cure process can be directly measured more precisely than with a rheometer in a shear plate set-up, because using an elastomer container gives a defined cross section for calculating the Young's modulus.
T2 - 20th European Conference on Composite Materials
CY - Lausanne, Switzerland
DA - 26.06.2022
KW - Cross linking
KW - Dynamic mechanical analysis (DMA)
KW - Thermoset polymers
KW - Cure process
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569651
UR - https://infoscience.epfl.ch/record/298799
SN - 978-2-9701614-0-0
VL - Vol. 5 - Applications and structures
SP - 181
EP - 186
PB - Composite Construction Laboratory (CCLab)
CY - Lausanne
AN - OPUS4-56965
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Azevedo do Nascimento, A.
A1 - Trappe, Volker
A1 - Diniz Melo, J. D.
A1 - Cysne Barbosa, A. P.
T1 - Fatigue behavior of self-healing glass fiber/epoxy composites with addition of poly (ethylene-co-methacrylic acid) (EMAA)
N2 - The interest in repair technologies for polymer composites has increased significantly over the last decades, due to the growing use of these materials in structural applications. In this study, poly (ethylene-co-methacrylic acid) (EMAA) was used as self-healing agent to glass fiber/epoxy composite. Materials with EMAA contents of 2 wt% and 5 wt% were manufactured using Resin Transfer Molding (RTM) and the effects of the healing agent on the properties were investigated using tensile tests and Dynamic Mechanical Analysis (DMA). Results show slight variation of properties, which was more pronounced as the content of EMAA increased. In addition, the healing efficiency was investigated through fatigue tests and the addition of higher content of EMAA increased the number of cycles to failure after the healing activation cycle.
KW - Fatigue
KW - Glass fiber-epoxy composites
KW - Self-healing
KW - Smart materials
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569661
DO - https://doi.org/10.1016/j.polymertesting.2022.107863
SN - 0142-9418
VL - 117
SP - 1
EP - 10
PB - Elsevier Ltd.
AN - OPUS4-56966
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lunkenheimer, P.
A1 - Loidl, A.
A1 - Riechers, Birte
A1 - Zaccone, A.
A1 - Samwer, K.
T1 - Thermal expansion and the glass transition
N2 - Melting is well understood in terms of the Lindemann criterion, which
essentially states that crystalline materials melt when the thermal vibrationsof their atoms become so vigorous that they shake themselves free of the binding forces. This picture does not necessarily have to hold for glasses, where the nature of the solid–liquid cross-over is highly debated. The Lindemann criterion implies that the thermal expansion coefficients of crystals are inversely proportional to their melting temperatures. Here we find that, in contrast, the thermal expansion coefficient of glasses decreases more strongly with increasing glass temperature, which marks the liquid–solid cross-over in this material class. However, this proportionality returns when the thermal expansion coefficient is scaled by the fragility, a measure of particle cooperativity. Therefore, for a glass to become liquid, it is not sufficient to simply overcome the interparticle binding energies.
Instead, more energy must be invested to break up the typical cooperative particle network that is common to glassy materials. The thermal expansion coefficient of the liquid phase reveals similar anomalous behaviour and is universally enhanced by a constant factor of approximately 3. These universalities allow the estimation of glass temperatures from thermal expansion and vice versa.
KW - Glass transition
KW - Lindemann criterion
KW - Thermal expansion
KW - Glass
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570267
DO - https://doi.org/10.1038/s41567-022-01920-5
SN - 1745-2473
SP - 1
EP - 7
PB - Nature Publishing Group
CY - London
AN - OPUS4-57026
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Reinmuth-Selzle, K.
A1 - Bellinghausen, I.
A1 - Leifke, A. L.
A1 - Backes, A. T.
A1 - Bothen, N.
A1 - Ziegler, K.
A1 - Weller, Michael G.
A1 - Saloga, J.
A1 - Schuppan, D.
A1 - Lucas, K.
A1 - Pöschl, U.
A1 - Fröhlich-Nowoisky, J.
T1 - Chemical modification by peroxynitrite enhances TLR4 activation of the grass pollen allergen Phl p 5
N2 - The chemical modification of aeroallergens by reactive oxygen and nitrogen species (ROS/RNS) may contribute to the growing prevalence of respiratory allergies in industrialized countries. Post-translational modifications can alter the immunological properties of proteins, but the underlying mechanisms and effects are not well understood. In this study, we investigate the Toll-like receptor 4 (TLR4) activation of the major birch and grass pollen allergens Bet v 1 and Phl p 5, and how the physiological oxidant peroxynitrite (ONOO–) changes the TLR4 activation through protein nitration and the formation of protein dimers and higher oligomers. Of the two allergens, Bet v 1 exhibited no TLR4 activation, but we found TLR4 activation of Phl p 5, which increased after modification with ONOO– and may play a role in the sensitization against this grass pollen allergen. We attribute the TLR4 activation mainly to the two-domain structure of Phl p 5 which may promote TLR4 dimerization and activation. The enhanced TLR4 signaling of the modified allergen indicates that the ONOO–-induced modifications affect relevant protein-receptor interactions. This may lead to increased sensitization to the grass pollen allergen and thus contribute to the increasing prevalence of allergies in the Anthropocene, the present era of globally pervasive anthropogenic influence on the environment.
KW - Bet v 1
KW - Birch pollen allergen
KW - Phl p 5
KW - Grass pollen
KW - Phleum pratense
KW - Betula pendula
KW - Nitration
KW - Nitrotyrosine
KW - Protein nitration
KW - Toll-like receptor 4
KW - Allergy
KW - Enhancement
KW - Oligomerization
KW - Dimerization
KW - TLR4 activation
KW - Air pollution
KW - Nitrogen oxides
KW - Inflammation
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570298
DO - https://doi.org/10.3389/falgy.2023.1066392
VL - 4
SP - 1
EP - 7
PB - Frontiers Media SA
CY - Lausanne, Switzerland
AN - OPUS4-57029
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lecompagnon, Julien
A1 - Hirsch, Philipp Daniel
A1 - Rupprecht, C.
A1 - Ziegler, Mathias
T1 - Nondestructive thermographic detection of internal defects using pixel-pattern based laser excitation and photothermal super resolution reconstruction
N2 - In this work, we present a novel approach to photothermal super resolution based thermographic resolution of internal defects using two-dimensional pixel pattern-based active photothermal laser heating in conjunction with subsequent numerical reconstruction to achieve a high-resolution reconstruction of internal defect structures. With the proposed adoption of pixelated patterns generated using laser coupled high-power DLP projector technology the complexity for achieving true two-dimensional super resolution can be dramatically reduced taking a crucial step forward towards widespread practical viability. Furthermore, based on the latest developments in high-power DLP projectors, we present their first application for structured pulsed thermographic inspection of macroscopic metal samples. In addition, a forward solution to the underlying inverse problem is proposed along with an appropriate heuristic to find the regularization parameters necessary for the numerical inversion in a laboratory setting. This allows the generation of synthetic measurement data, opening the door for the application of machine learning based methods for future improvements towards full automation of the method. Finally, the proposed method is experimentally validated and shown to outperform several established conventional thermographic testing techniques while conservatively improving the required measurement times by a factor of 8 compared to currently available photothermal super resolution techniques.
KW - Thermography
KW - Super resolution
KW - NDT
KW - Inspection
KW - Internal defects
KW - DMD
KW - DLP
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570551
DO - https://doi.org/10.1038/s41598-023-30494-2
SN - 2045-2322
VL - 13
SP - 1
EP - 13
PB - Nature Research
AN - OPUS4-57055
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Krüger, Jörg
A1 - Bonse, Jörn
T1 - Editorial: Special Issue “Advanced Pulse Laser Machining Technology"
N2 - “Advanced Pulse Laser Machining Technology” is a rapidly growing field that can be tailored to special industrial and scientific applications. This is significantly driven by the availability of high-repetition-rate laser sources and novel beam delivery concepts.
KW - Editorial
KW - Pulse Laser
KW - Laser Machining
KW - Ultrashort laser pulses
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568410
DO - https://doi.org/10.3390/ma16020819
SN - 1996-1944
VL - 16
IS - 2
SP - 1
EP - 4
PB - MDPI
CY - Basel
AN - OPUS4-56841
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Getenet, M.
A1 - Otálora, F.
A1 - Emmerling, Franziska
A1 - Al-Sabbagh, Dominik
A1 - García-Ruiz, J. M.
T1 - Mineral precipitation and hydrochemical evolution through evaporitic processes in soda brines (East African Rift Valley)
N2 - Soda lakes of the East African Rift Valley are hyperalkaline, hypersaline lakes extremely enriched in Na+, K+, Cl−, CO32−, HCO3−, and SiO2. In this paper, we investigate the chemical evolution in these lakes and the production of chemical sediments by salt precipitation via evaporation. Water samples from tributary springs and three lakes (Magadi, Nasikie Engida and Natron) have been experimentally studied by in-situ X-ray diffraction during evaporation experiments to characterize the sequence of mineral precipitation. These data are complemented by ex-situ diffraction studies, chemical analyses and thermodynamic hydrochemical calculations producing detailed information on the activity of all solution species and the saturation state of all minerals potentially generated by the given composition. Major minerals precipitating from these samples are sodium carbonates/bicarbonates as well as halite. The CO3/HCO3 ratio, controlled by pH, is the main factor defining the Na‑carbonates precipitation sequence: in lake brines where CO3/HCO3 > 1, trona precipitates first whereas in hot springs, where CO3/HCO3 ≪ 1, nahcolite precipitates instead of trona, which forms later via partial dissolution of nahcolite. Precipitation of nahcolite is possible only at lower pH values (pCO2 higher than −2.7) explaining the distribution of trona and nahcolite in current lakes and the stratigraphic sequences. Later, during evaporation, thermonatrite precipitates, normally at the same time as halite, at a very high pH (>11.2) after significant depletion of HCO3− due to trona precipitation. The precipitation of these soluble minerals increases the pH of the brine and is the main factor contributing to the hyperalkaline and hypersaline character of the lakes. Villiaumite, sylvite, alkaline earth carbonates, fluorapatite and silica are also predicted to precipitate, but most of them have not been observed in evaporation experiments, either because of the small amount of precipitates produced, kinetic effects delaying the nucleation of some phases, or by biologically induced effects in the lake chemistry that are not considered in our calculations. Even in these cases, the chemical composition in the corresponding ions allows for discussion on their accumulation and the eventual precipitation of these phases. The coupling of in-situ and ex-situ experiments and geochemical modelling is key to understanding the hydrogeochemical and hydroclimatic conditions of soda lakes, evaporite settings, and potentially soda oceans of early Earth and other extraterrestrial bodies.
KW - Crystallization sequence
KW - Hydrochemical evolution
KW - Alkaline brines
KW - Sodium carbonate minerals
KW - Soda lakes
KW - Evaporite deposits
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568431
DO - https://doi.org/10.1016/j.chemgeo.2022.121222
SN - 0009-2541
VL - 616
SP - 1
EP - 13
PB - Elsevier
CY - New York, NY
AN - OPUS4-56843
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kader, A.
A1 - Kaufmann, Jan Ole
A1 - Mangarova, D. B.
A1 - Moeckel, J.
A1 - Adams, L. C.
A1 - Brangsch, J.
A1 - Heyl, J. L.
A1 - Zhao, J.
A1 - Verlemann, C.
A1 - Karst, U.
A1 - Collettini, F.
A1 - Auer, T. A.
A1 - Hamm, B.
A1 - Makowski, M. R.
T1 - Collagen-specific molecular magnetic resonance imaging of prostate cancer
N2 - Constant interactions between tumor cells and the extracellular matrix (ECM) influence the progression of prostate cancer (PCa). One of the key components of the ECM are collagen fibers, since they are responsible for the tissue stiffness, growth, adhesion, proliferation, migration, invasion/metastasis, cell signaling, and immune recruitment of tumor cells. To explore this molecular marker in the content of PCa, we investigated two different tumor volumes (500 mm3 and 1000 mm3) of a xenograft mouse model of PCa with molecular magnetic resonance imaging (MRI) using a collagen-specific probe. For in vivo MRI evaluation, T1-weighted sequences before and after probe administration were analyzed. No significant signal difference between the two tumor volumes could be found. However, we detected a significant difference between the signal intensity of the peripheral tumor area and the central area of the tumor, at both 500 mm3 (p < 0.01, n = 16) and at 1000 mm3 (p < 0.01, n = 16). The results of our histologic analyses confirmed the in vivo studies: There was no significant difference in the amount of collagen between the two tumor volumes (p > 0.05), but within the tumor, higher collagen expression was observed in the peripheral area compared with the central area of the tumor. Laser ablation with inductively coupled plasma mass spectrometry further confirmed these results. The 1000 mm3 tumors contained 2.8 +- 1.0% collagen and the 500 mm3 tumors contained 3.2 +- 1.2% (n = 16). There was a strong correlation between the in vivo MRI data and the ex vivo histological data (y = 0.068x + 1.1; R2 = 0.74) (n = 16). The results of elemental analysis by inductively coupled plasma mass spectrometry supported the MRI data (y = 3.82x + 0.56; R2 = 0.79; n = 7). MRI with the collagen-specific probe in PCa enables differentiation between different tumor areas. This may help to differentiate tumor from healthy tissue, potentially identifying tumor areas with a specific tumor biology.
KW - Molecular imaging
KW - Magnetic resonance imaging
KW - MRI
KW - Prostate cancer
KW - Collagen
KW - Laser ablation-inductively coupled plasma-mass spectroscopy
KW - EP-3533
KW - Peptide probe
KW - Gd-DOTA
KW - Contrast agent
KW - Tumor
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568449
DO - https://doi.org/10.3390/ijms24010711
SN - 1422-0067
SN - 1661-6596
VL - 24
IS - 1
SP - 1
EP - 13
PB - MDPI
CY - Basel
AN - OPUS4-56844
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Krankenhagen, Rainer
T1 - Influence of Moisture in Concrete on the Photothermal Response—A New Approach for a Measurement Method?
N2 - Recently, the photothermal determination of the thermophysical properties of concrete under lab conditions was reported. Their values are mainly needed to look at the energy consumption of buildings. Additionally, changes in their values in relation to the initial state might also be a good indicator for material quality or for moisture. The present contribution explains the photothermal method in a more general way to indicate the potential for on-site application. Secondly, a special application case is regarded: the detection of moisture in concrete. Two concrete samples were soaked with water, followed by a drying period, to obtain different levels of water penetration. The water contents were determined by weighing, and the photothermal response was measured. The results show a large influence on the measured temperature transients, which is larger than expected from the original simple model. They clearly provide two points: the photothermal method is suited to detect moisture in concrete, but the magnitude of the actual measurement effect is not yet understood.
KW - Thermal effusivity
KW - Thermal conductivity
KW - Moisture
KW - Reflectivity
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570439
DO - https://doi.org/10.3390/app13052768
VL - 13
IS - 5
SP - 1
EP - 18
PB - MDPI
CY - Basel, Switzerland
AN - OPUS4-57043
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Rüdenauer, I.
A1 - Quack, D.
A1 - Schlegel, Moritz-Caspar
T1 - kWh versus Euro – What is the most effective way to inform about efficient products?
N2 - Energy efficient products often have a higher purchase price than less efficient alternatives. However, the life cycle costs are often lower due to the lower operating costs. From a purely economic point of view, efficient appliances are not only more ecological but often also more economical and, accordingly, should be purchased more frequently than less efficient appliances. However, this is not always the case. Information deficits are one of the major reasons of this discrepancy: the purchase price is visible during the purchasing process, but the follow-up costs are not, at least not in their exact amount. The EU Energy Label can be considered as a solution to close this gap. During the past decades, there has been a discussion on whether it would be better to communicate the monetary costs associated with energy consumption, since their calculation by the consumer is difficult or needs a high level of cognitive effort.
In this study, experiments and field studies on a total of 19 product groups were evaluated with regard to the question of whether the indication of costs instead of physical units affects the decision-making process of the consumer. It has been assessed under which circumstances it might positively influence the purchase decision of the customer, i.e. helping him or her to arrive at a more “energy efficient” decision. Overall, the results indicate that monetary claims possibly exceed the effect of claims on a physical basis when the costs or the differences between the alternatives available seem “relevant” to the consumer.
T2 - EEDAL’21
CY - Toulouse, France
DA - 01.06.2021
KW - Energy Labelling
KW - Ecodesign
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570454
SN - 978-92-76-99908-9
DO - https://doi.org/10.2760/356891
SP - 358
EP - 367
AN - OPUS4-57045
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Veh, G.
A1 - Lützow, N.
A1 - Tamm, J.
A1 - Luna, L. V.
A1 - Hugonnet, R.
A1 - Vogel, Kristin
A1 - Geertsema, M.
A1 - Clague, J. J.
A1 - Korup, O.
T1 - Less extreme and earlier outbursts of ice-dammed lakes since 1900
N2 - Episodic failures of ice-dammed lakes have produced some of the largest floods in history, with disastrous consequences for communities in high mountains. Yet, estimating changes in the activity of ice-dam failures through time remains controversial because of inconsistent regional flood databases. Here, by collating 1,569 ice-dam failures in six major mountain regions, we systematically assess trends in peak discharge, volume, annual timing and source elevation between 1900 and 2021. We show that extreme peak flows and volumes (10 per cent highest) have declined by about an order of magnitude over this period in five of the six regions, whereas median flood discharges have fallen less or have remained unchanged.
Ice-dam floods worldwide today originate at higher elevations and happen about six weeks earlier in the year than in 1900. Individual ice-dammed lakes with repeated outbursts show similar negative trends in magnitude and earlier occurrence, although with only moderate correlation to glacier thinning8. We anticipate that ice dams will continue to fail in the near future, even as glaciers thin and recede. Yet widespread deglaciation, projected for nearly all regions by the end of the twenty-first century9, may bring most outburst activity to a halt.
KW - Outburst floods
KW - Bayesian hierachical modelling
KW - Trends in extreme events
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570529
DO - https://doi.org/10.1038/s41586-022-05642-9
VL - 614
IS - 7949
SP - 701
EP - 707
AN - OPUS4-57052
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kraft, Sebastian
A1 - Schille, J.
A1 - Bonse, Jörn
A1 - Löschner, U.
A1 - Krüger, Jörg
T1 - X‑ray emission during the ablative processing of biological materials by ultrashort laser pulses
N2 - The ablative laser processing with ultrashort pulsed laser beams may cause secondary emission of hazardous X-rays. While the effect has recently been proven to be considered in working safety regulations when processing technical materials, such as metals, the X-ray emission rates during the ablative processing of biological tissue materials are widely unexplored yet.
Therefore, biological materials like water, isotonic saline solution, pig eyes, and human teeth were ablated with ultrashort laser pulses of 1030 nm wavelength, 600 fs pulse duration and 5 kHz pulse repetition rate, aiming to mimic typical surgery situations. Simultaneously, in-situ X-ray dose rate measurements were performed at a short distance from the plasma to display potential X-ray emission. For all four studied biological materials, our measurements prove the secondary emission of laser-induced X-rays.
KW - Ultrashort pulsed laser
KW - Laser-induced X-ray emission
KW - Ophthalmology
KW - Dentistry
KW - Secondary hazard
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569960
DO - https://doi.org/10.1007/s00339-023-06440-4
SN - 0947-8396
VL - 129
IS - 3
SP - 1
EP - 8
PB - Springer
AN - OPUS4-56996
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kohlbrecher, J.
A1 - Breßler, Ingo
T1 - Updates in SASfit for fitting analytical expressions and numerical models to small-angle scattering patterns
N2 - Small-angle scattering is an increasingly common method for characterizing particle ensembles in a wide variety of sample types and for diverse areas of application. SASfit has been one of the most comprehensive and flexible curve-fitting programs for decades, with many specialized tools for various fields. Here, a selection of enhancements and additions to the SASfit program are presented that may be of great benefit to interested and advanced users alike: (a) further development of the technical basis of the program, such as new numerical algorithms currently in use, a continuous integration practice for automated building and packaging of the software, and upgrades on the plug-in system for easier adoption by third-party developers; (b) a selection of new form factors for anisotropic scattering patterns and updates to existing form factors to account for multiple scattering effects; (c) a new type of a very flexible distribution called metalog [Keelin (2016). Decis. Anal. 13, 243–277], and regularization techniques such as the expectation-maximization method [Dempster et al. (1977). J. R. Stat. Soc. Ser. B (Methodological), 39, 1–22; Richardson (1972) J. Opt. Soc. Am. 62, 55; Lucy (1974). Astron. J. 79, 745; Lucy (1994). Astron. Astrophys. 289, 983–994], which is compared with fits of analytical size distributions via the non-linear least-squares method; and (d) new structure factors, especially for ordered nano- and meso-scaled material systems, as well as the Ornstein–Zernike solver for numerical determination of particle interactions and the resulting structure factor when no analytical solution is available, with the aim of incorporating its effects into the small-angle scattering intensity model used for fitting with SASfit.
KW - Small-angle scattering
KW - Numerical models
KW - Structure factors
KW - Regularization
KW - SAXS
KW - SANS
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565069
DO - https://doi.org/10.1107/S1600576722009037
SN - 0021-8898
SN - 1600-5767
VL - 55
IS - 6
SP - 1677
EP - 1688
PB - Wiley-Blackwell
CY - Oxford
AN - OPUS4-56506
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Xing, N.
A1 - Höfler, T.
A1 - Hearn, C. J.
A1 - Nascimento, M.
A1 - Camps Paradell, G.
A1 - McMahon, Dino Peter
A1 - Kunec, D.
A1 - Osterrieder, N.
A1 - Cheng, H. H.
A1 - Trimpert, J.
T1 - Fast-forwarding evolution - Accelerated adaptation in a proofreading-deficient hypermutator herpesvirus
N2 - Evolution relies on the availability of genetic diversity for fitness-based selection. However, most deoxyribonucleic acid (DNA) viruses employ DNA polymerases (Pol) capable of exonucleolytic proofreading to limit mutation rates during DNA replication. The relative genetic stability produced by high-fidelity genome replication can make studying DNA virus adaptation and evolution an intensive endeavor, especially in slowly replicating viruses. Here, we present a proofreading-impaired Pol mutant (Y547S) of Marek’s disease virus that exhibits a hypermutator phenotype while maintaining unimpaired growth in vitro and wild-type (WT)-like pathogenicity in vivo. At the same time, mutation frequencies observed in Y547S virus populations are 2–5-fold higher compared to the parental WT virus. We find that Y547S adapts faster to growth in originally non-permissive cells, evades pressure conferred by antiviral inhibitors more efficiently, and is more easily attenuated by serial passage in cultured cells compared to WT. Our results suggest that hypermutator viruses can serve as a tool to accelerate evolutionary processes and help identify key genetic changes required for adaptation to novel host cells and resistance to antiviral therapy. Similarly, the rapid attenuation achieved through adaptation of hypermutators to growth in cell culture enables identification of genetic changes underlying attenuation and virulence, knowledge that could practically exploited, e.g. in the rational design of vaccines.
KW - Polymerase mutant
KW - Proofreading deficient
KW - Hypermutation
KW - Adaption
KW - DNA polymerase
KW - Marek's Disease Virus
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565631
DO - https://doi.org/10.1093/ve/veac099
SN - 2057-1577
VL - 8
IS - 2
SP - 1
EP - 11
PB - Oxford University Press
CY - Oxford, UK
AN - OPUS4-56563
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Maisels, A.
A1 - Hiller, A.
A1 - Simon, Franz-Georg
T1 - Chemical Recycling for Plastic Waste: Status and Perspectives
N2 - Industrial-scale mechanical recycling of plastics has been established for years, but has technical and economic limits. Chemical recycling processes lead back to monomers or to the raw materials, so that in the end new goods can be produced for all areas of application of plastics. The variety of chemical recycling processes is large. The capacities of the plants are still low today. The profitability of the plants is strongly influenced by the price of oil; the profitability limit is currently between 50 and 60 US $ per barrel.
KW - Chemical recycling
KW - Plastic waste
KW - Circular economy
KW - Pyrolysis
KW - Solvolysis
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565700
DO - https://doi.org/10.1002/cben.202200024
SN - 2196-9744
VL - 9
IS - 6
SP - 541
EP - 555
PB - Wiley-VCH GmbH
CY - Weinheim
AN - OPUS4-56570
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bulling, Jannis
A1 - Jurgelucks, B.
A1 - Prager, Jens
A1 - Walther, A.
T1 - Defect reconstruction in a two-dimensional semi-analytical waveguide model via derivative-based optimization
N2 - This paper considers an indirect measurement approach to reconstruct a defect in a two-dimensional waveguide model for a non-destructive ultrasonic inspection via derivative-based optimization. The propagation of the mechanical waves is simulated by the scaled boundary finite element method that builds on a semi-analytical approach. The simulated data are then fitted to given data associated with the reflected waves from a defect which is to be reconstructed. For this purpose, we apply an iteratively regularized Gauss-Newton method in combination with algorithmic differentiation to provide the required derivative information accurately and efficiently. We present numerical results for three kinds of defects, namely, a crack, delamination, and corrosion. The objective function and the properties of the reconstruction method are investigated. The examples show that the parameterization of the defect can be reconstructed efficiently as well as robustly in the presence of noise.
KW - Mechanical waves
KW - Corrosion
KW - Finite-element analysis
KW - Ultrasonic testing
KW - Nondestructive testing techniques
KW - Symbolic computation
KW - Materials analysis
KW - MATLAB
KW - Newton Raphson method
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565485
DO - https://doi.org/10.1121/10.0013574
VL - 152
IS - 2
SP - 1217
EP - 1229
PB - AIP Publ.
CY - Melville, NY
AN - OPUS4-56548
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Riedel, Soraya
A1 - Jaut, Valerie
A1 - Schneider, Rudolf
T1 - Ergometrine sensing in rye flour by a magnetic bead-based immunoassay followed by flow injection analysis with amperometric detection
N2 - A certain group of mycotoxins, the ergot alkaloids, has caused countless deaths throughout human history. They are found in rye and other cereals and ingesting contaminated foods can cause serious health problems. To identify contaminated food exceeding the legal limits for ergot alkaloids, a portable and cost-effective test system is of great interest to the food industry. Rapid analysis can be achieved by screening for a marker compound, for which we chose ergometrine. We developed a magnetic bead-based immunoassay for ergometrine with amperometric detection in a flow injection system using a handheld potentiostat and a smartphone. With this assay a limit of detection of 3 nM (1 μg/L) was achieved. In spiked rye flour, ergometrine levels from 25 to 250 μg/kg could be quantified. All results could be verified by optical detection. The developed assay offers great promise to meet the demand for on-site ergometrine detection in the food industry.
KW - Ergot alkaloids
KW - Amperometry
KW - Magnetic beads
KW - Immunoassay
KW - Food analysis
KW - Fow injection analysis
KW - Mycotoxins
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565906
DO - https://doi.org/10.1016/j.talanta.2022.124172
SN - 0039-9140
N1 - Geburtsname von Riedel, Soraya: Höfs, S. - Birth name of Riedel, Soraya: Höfs, S.
VL - 254
IS - 124172
SP - 1
EP - 8
PB - Elsevier B.V.
AN - OPUS4-56590
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Malakhov, A.
A1 - Epishin, A.
A1 - Denisov, I.
A1 - Saikov, I.
A1 - Nolze, Gert
T1 - Morphology and Structure of Brass–Invar Weld Interface after Explosive Welding
N2 - This paper presents the results of a study of the morphology and structure at the weld interface in a brass–Invar bimetal, which belongs to the class of so-called thermostatic bimetals, or thermobimetals. The structure of the brass–Invar weld interface was analyzed using optical microscopy and scanning electron microscopy (SEM), with the use of energy-dispersive X-ray (EDX) spectrometry and back-scattered electron diffraction (BSE) to identify the phases. The distribution of the crystallographic orientation of the grains at the weld interface was obtained using an e-Flash HR electron back-scatter diffraction (EBSD) detector and a forward-scatter detector (FSD). The results of the study indicated that the weld interface had the wavy structure typical of explosive welding. The wave crests and troughs showed the presence of melted zones consisting of a disordered Cu–Zn–Fe–Ni solid solution and undissolved Invar particles. The pattern quality map showed that the structure of brass and Invar after explosive welding consisted of grains that were strongly elongated towards the area of the highest intensive plastic flow. In addition, numerous deformation twins, dislocation accumulations and shear bands were observed. Thus, based on the results of this study, the mechanism of Cu–Zn–Fe–Ni structure formation can be proposed.
KW - Explosive welding
KW - Thermobimetal
KW - Grain structure
KW - Brass
KW - Invar
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565964
DO - https://doi.org/10.3390/ma15238587
SN - 1996-1944
VL - 15
IS - 23
SP - 1
EP - 10
PB - MDPI
AN - OPUS4-56596
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Böttcher, Katrin
A1 - Schmitt Rahner, M.
A1 - Stolzenberg, U.
A1 - Kraft, Sebastian
A1 - Bonse, Jörn
A1 - Feist, C.
A1 - Albrecht, D.
A1 - Pullner, B.
A1 - Krüger, Jörg
T1 - Worst-case X-ray photon energies in ultrashort pulse laser processing
N2 - Ultrashort pulse laser processing can result in the secondary generation of unwanted X-rays if a critical laser irradiance of about 10^13 W/cm^2 is exceeded. Spectral X-ray emissions were investigated during the processing of tungsten and steel using three complementary spectrometers (based on CdTe and silicon drift detectors) simultaneously for the identification of a worst-case spectral scenario. Therefore, maximum X-ray photon energies were determined, and corresponding dose equivalent rates were calculated. An ultrashort pulse laser workstation with a pulse duration of 274 fs, a center wavelength of 1030 nm, pulse repetition rates between 50 kHz and 200 kHz, and a Gaussian laser beam focused to a spot diameter of 33 µm was employed in a single pulse and burst laser operation mode. Different combinations of laser pulse energy and repetition rate were utilized, keeping the average laser power constant close to the maximum power of 20 W. Peak irradiances ranging from 7.3 × 10^13 W/cm^2 up to 3.0 × 10^14 W/cm^2 were used. The X-ray dose equivalent rate increases for lower repetition rates and higher pulse energy if a constant average power is used. Laser processing with burst mode significantly increases the dose rates and the X-ray photon energies. A maximum X-ray photon energy of about 40 keV was observed for burst mode processing of tungsten with a repetition rate of 50 kHz and a peak irradiance of 3 × 10^14 W/cm^2.
KW - Ultrashort pulsed laser
KW - X-ray emission
KW - X-ray spectrum
KW - X-ray energies
KW - Radiation protection
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-566176
DO - https://doi.org/10.3390/ma15248996
VL - 15
IS - 24
SP - 1
EP - 17
PB - MDPI
AN - OPUS4-56617
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kinne, R. W.
A1 - Gunnella, F.
A1 - Kunisch, E.
A1 - Heinemann, S.
A1 - Nies, B.
A1 - Maenz, S.
A1 - Horbert, V.
A1 - Illerhaus, Bernhard
A1 - Huber, R.
A1 - Firkowska-Boden, I.
A1 - Bossert, J.
A1 - Jandt, K. D.
A1 - Sachse, A.
A1 - Bungartz, M.
A1 - Brinkmann, O.
T1 - Performance of calcium phosphate cements in the augmentation of sheep vertebrae - An ex vivo study
N2 - Oil-based calcium phosphate cement (Paste-CPC) shows not only prolonged shelf life and injection times, but also improved cohesion and reproducibility during application, while retaining the advantages of fast setting, mechanical strength, and biocompatibility. In addition, poly(L-lactideco-glycolide) (PLGA) fiber reinforcement may decrease the risk for local extrusion. Bone defects (diameter 5 mm; depth 15 mm) generated ex vivo in lumbar (L) spines of female Merino sheep (2–4 years) were augmented using: (i) water-based CPC with 10% PLGA fiber reinforcement (L3); (ii) Paste-CPC (L4); or (iii) clinically established polymethylmethacrylate (PMMA) bone cement (L5). Untouched (L1) and empty vertebrae (L2) served as controls. Cement performance was analyzed using micro-computed tomography, histology, and biomechanical testing. Extrusion was comparable for Paste-CPC(-PLGA) and PMMA, but significantly lower for CPC + PLGA. Compressive strength and Young’s modulus were similar for Paste-CPC and PMMA, but significantly higher compared to those for empty defects and/or CPC + PLGA. Expectedly, all experimental groups showed significantly or numerically lower compressive strength and Young’s modulus than those of untouched controls. Ready-to-use Paste-CPC demonstrates a performance similar to that of PMMA, but improved biomechanics compared to those of water-based CPC + PLGA, expanding the therapeutic arsenal for bone defects. O, significantly lower extrusion of CPC + PLGA fibers into adjacent lumbar spongiosa may help to reduce the risk of local extrusion in spinal surgery.
KW - Sheep
KW - PMMA
KW - Calcium phosphate bone cement
KW - Oil-based
KW - Ready-to-use
KW - Water-based
KW - Micro-CT
KW - Compressive strength
KW - Young’s modulus
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569072
DO - https://doi.org/10.3390/ma14143873
SN - 1996-1944
VL - 14
IS - 14
SP - 1
EP - 12
PB - MDPI
CY - Basel
AN - OPUS4-56907
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mitu, M.
A1 - Razus, D.
A1 - Schröder, Volkmar
T1 - Laminar burning velocities of hydrogen-blended methane-air and natural gas-air mixtures, calculated from the early stage of p(t) records in a spherical vessel
N2 - The flammable hydrogen-blended methane–air and natural gas–air mixtures raise specific safety and environmental issues in the industry and transportation; therefore, their explosion characteristics such as the explosion limits, explosion pressures, and rates of pressure rise have significant importance from a safety point of view. At the same time, the laminar burning velocities are the most useful parameters for practical applications and in basic studies for the validation of reaction mechanisms and modeling turbulent combustion. In the present study, an experimental and numerical study of the effect of hydrogen addition on the laminar burning velocity (LBV) of methane–air and natural gas–air mixtures was conducted, using mixtures with equivalence ratios within 0.90 and 1.30 and various hydrogen fractions rH within 0.0 and 0.5. The experiments were performed in a 14 L spherical vessel with central ignition at ambient initial conditions. The LBVs were calculated from p(t) data, determined in accordance with EN 15967, by using only the early stage of flame propagation. The results show that hydrogen addition determines an increase in LBV for all examined binary flammable mixtures. The LBV variation versus the fraction of added hydrogen, rH, follows a linear trend only at moderate hydrogen fractions. The further increase in rH results in a stronger variation in LBV, as shown by both experimental and computed LBVs. Hydrogen addition significantly changes the thermal diffusivity of flammable CH4–air or NG–air mixtures, the rate of heat release, and the concentration of active radical species in the flame front and contribute, thus, to LBV variation.
KW - Hydrogen
KW - Methane
KW - Natural gas
KW - Laminar burning velocity (LBV)
KW - Closed vessel combustion
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569083
DO - https://doi.org/10.3390/en14227556
SN - 1996-1073
VL - 14
IS - 22
SP - 1
EP - 16
PB - MDPI
CY - Basel
AN - OPUS4-56908
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Neuhold, S.
A1 - Algermissen, D.
A1 - Drissen, P.
A1 - Adamczyk, Burkart
A1 - Presoly, P.
A1 - Sedlazeck, K. P.
A1 - Schenk, J.
A1 - Raith, J. G.
A1 - Pomberger, R.
A1 - Vollprecht, D.
T1 - Tailoring the FeO/SiO2 Ratio in Electric Arc Furnace Slags to Minimize the Leaching of Vanadium and Chromium
N2 - Based on recently published research on leaching control mechanisms in electric arc furnace (EAF) slags, it is assumed that a FeO/SiO2 ratio of around one leads to low leached V and Cr concentrations. This ratio influences the mineral phase composition of the slag toward higher amounts of spinel and a lower solubility of calcium silicate phases by suppressing the formation of magnesiowuestite and highly soluble calcium silicate phases. To evaluate this hypothesis, laboratory and scaled up tests in an EAF pilot plant were performed on slag samples characterized by elevated V and Cr leaching and a high FeO/SiO2 ratio. Prior to the melting experiments, the optimum FeO/SiO2 ratio was calculated via FactSageTM. In the melting experiments, the ratio was adjusted by adding quartz sand, which also decreased the basicity (CaO/SiO2) of the slag. As a reference, remelting experiments without quartz sand addition were conducted and additionally, the influence of the cooling rate of the slag was examined. The remelted (without quartz sand) and the remelted modified slags (with quartz sand) were analyzed chemically and mineralogically and the leaching behavior was investigated. The modification of the slags yielded a minimized release of V and Cr, supporting the hypothesis that the FeO/SiO2 ratio influences the mineralogy and the leaching behavior.
KW - Electric arc furnace (EAF) slags
KW - FactSageTM calculations
KW - Leaching control mechanisms
KW - Melting experiments
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571517
DO - https://doi.org/10.3390/app10072549
VL - 10
IS - 7
SP - 1
EP - 18
PB - MDPI
AN - OPUS4-57151
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Flierl, Lukas
A1 - Rienitz, Olaf
A1 - Vogl, Jochen
A1 - Pramann, Axel
T1 - An advancement of the gravimetric isotope mixture method rendering the knowledge of the spike purity superfluous
N2 - The gravimetric isotope mixture method is the primary method to determine absolute isotope ratios. This method, however, depends on the existence of suitable spike materials and knowledge of their purities. Determining the purity of the spikes can be tedious and labour-intensive. In this publication, an advancement of the gravimetric isotope mixture method, rendering the determination of the purity of the spike materials unnecessary, is presented. The advancement combines mass spectrometry and ion chromatography leading to an approach being independent of the purity of the spike materials. In the manuscript the mathematical background and the basic idea of the novel approach are described using a two-isotope system like copper or lithium.
KW - Isotope amount ratios
KW - Metrology
KW - Mass spectrometry
KW - Ion chromatography
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608726
DO - https://doi.org/10.1007/s00216-024-05465-9
SP - 5325
EP - 5333
PB - Springer Science and Business Media LLC
AN - OPUS4-60872
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stolar, Tomislav
A1 - Pearce, Ben K.D.
A1 - Etter, Martin
A1 - Truong, Khai-Nghi
A1 - Ostojić, Tea
A1 - Krajnc, Andraž
A1 - Mali, Gregor
A1 - Rossi, Barbara
A1 - Molčanov, Krešimir
A1 - Lončarić, Ivor
A1 - Meštrović, Ernest
A1 - Užarević, Krunoslav
A1 - Grisanti, Luca
T1 - Base-pairing of uracil and 2,6-diaminopurine: from cocrystals to photoreactivity
N2 - We show that the non-canonical nucleobase 2,6-diaminopurine (D) spontaneously base pairs with uracil (U) in water and the solid state without the need to be attached to the ribose-phosphate backbone. Depending on the reaction conditions, D and U assemble in thermodynamically stable hydrated and anhydrated D-U base-paired cocrystals. Under UV irradiation, an aqueous solution of D-U base-pair undergoes photochemical degradation, while a pure aqueous solution of U does not. Our simulations suggest that D may trigger the U photodimerization and show that complementary base-pairing modifies the photochemical properties of nucleobases, which might have implications for prebiotic chemistry.
KW - Mechanochemistry
KW - In situ monitoring
KW - Cocrystals
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608622
DO - https://doi.org/10.1016/j.isci.2024.109894
VL - 27
IS - 6
SP - 1
EP - 14
PB - Elsevier Inc.
AN - OPUS4-60862
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Davison, Nathan
A1 - Hemingway, Jack M.
A1 - Wills, Corinne
A1 - Stolar, Tomislav
A1 - Waddell, Paul G.
A1 - Dixon, Casey M.
A1 - Barron, Luke
A1 - Dawson, James A.
A1 - Lu, Erli
T1 - Mechanochemical Synthesis of a Sodium Anion Complex [Na+(2,2,2-cryptand)Na–] and Studies of Its Reactivity: Two-Electron and One-Electron Reductions
N2 - Group 1 metal molecular chemistry is dominated by a +1 oxidation state, while a 0 oxidation state is widespread in the metals. A more exotic, yet still available, oxidation state of group 1 metal is −1, i.e., alkalide. Reported as early as the 1970s, the alkalides appear in every modern inorganic chemistry textbook as an iconic chemical curiosity, yet their reactivity remains unexplored. This is due to their synthetic hurdles. In this work, we report the first facile synthesis of the archetypical alkalide complex, [Na+(2,2,2-cryptand)Na–], which allows us to unveil a versatile reactivity profile of this once exotic species.
KW - Mechanochemistry
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608632
DO - https://doi.org/10.1021/acs.inorgchem.4c02914
VL - 63
IS - 32
SP - 15247
EP - 15258
PB - American Chemical Society (ACS)
AN - OPUS4-60863
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Giv, Ali Nemati
A1 - Asante, Bright
A1 - Yan, Libo
A1 - Kasal, Bohumil
T1 - Shear performance and durability of adhesively bonded spruce wood-concrete composite joints: Effects of indoor and outdoor environmental conditions, mechanical load, and their coupled effect
N2 - A long-term study was conducted on double-lap spruce wood-concrete joints to investigate their shear strength and stiffness over a 12-month period. These joints were manufactured using both wet and dry processes, each incorporating two adhesive types for bonding the wood to the concrete: a brittle epoxy and a ductile polyurethane (PUR). The experimental design exposed the joints to three specific long-term environments: (1) outdoor exposure, (2) indoor conditions with applied load, and (3) outdoor conditions with applied load. The wood concrete joints exposed to outdoor conditions were subjected to destructive shear testing at intervals of 0 (serving as the reference sample), 2, 4, 6, and 12 months, respectively. For joints subjected to both indoor and outdoor conditions with shear loading, the shear deformation of joints was monitored continuously over the 12 months before performing the destructive tests. A gradual reduction in the shear stiffness and strength of dry joints (produced using the dry bond method) exposed to outdoor conditions was observed over a 12-month period, primarily due to bond failure at the concrete-adhesive interface. The wet joints exhibited no degradation in shear stiffness and strength across long-term conditions over the same period. The bond failure observed in dry joints was predominantly associated with stresses arising from dimensional changes in the wood. No degradation was found in the cross-linking density of the adhesive or in the concrete’s compressive stiffness and strength.
KW - Adhesively bonded joints
KW - Long-term study
KW - Ductile PUR
KW - Brittle epoxy
KW - Outdoor condition
KW - Mechanical load
KW - Indoor condition
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608878
DO - https://doi.org/10.1016/j.conbuildmat.2024.136905
VL - 436
SP - 1
EP - 22
PB - Elsevier BV
AN - OPUS4-60887
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wegner, Karl David
A1 - Hildebrandt, N.
T1 - Near infrared quantum dots for biosensing and bioimaging
N2 - Quantum dots (QDs) possess unique optoelectronic properties, which make them very attractive to be used as optical probes in biosensing and bioimaging applications. The strong absorbance and light scattering of biological compounds like tissue and blood in the visible range pose a problem. However, if optical probes emitting in the near-infrared (NIR) range are used, scattering, absorption, and autofluorescence of biological components are strongly reduced. This allows for an increased light penetration depth and higher spatial and temporal resolution for the investigation of biological processes. The synthesis and application of NIR emitting QDs is a fast-growing research field and the benefits of using QDs were demonstrated for a variety of applications, such as photoelectrochemical biosensor, in vivo vascular imaging, and fluorescence-guided surgery. This article reviews the state-of-the-art developments in the preparation of NIR/IR QDs and highlights the latest research about their utilization in biosensing and bioimaging applications.
KW - Quantum dots
KW - Near-infrared
KW - Biosensing
KW - Bioimaging
KW - NIR-II / SWIR
KW - Advanced nanomaterials
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609708
SN - 0165-9936
DO - https://doi.org/10.1016/j.trac.2024.117922
VL - 180
SP - 1
EP - 19
PB - Elsevier B.V.
AN - OPUS4-60970
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mellios, Nikolaos
A1 - Kruschwitz, Sabine
A1 - Spyrdis, Panagiotis
T1 - Performance Prediction of Anchors in SFRC using Minimally Invasive and Non‐Destructive Techniques
N2 - AbstractFastenings are crucial for the upgrade of existing structures, by either enhancing structural components or modernising and expanding structures and structural systems. Whilst concrete is prevailing in the existing building stock, new types of concrete composites are increasingly used to improve the sustainability and overall structural performance of built assets. The addition of short dispersed fibres is a material technology with several applications. This paper addresses the synergy of fastening elements, introducing localised loads in concrete substrates, and of fibres, particularly in terms of the fibre orientation and density in the load application area, which is a significant quality aspect. The possibility to forecast this synergy based on non‐destructive or minimally invasive testing methods is an efficient tool to increase confidence in the design load‐bearing performance of the anchorages. Initially, previous literature and own investigations on such techniques are presented. Furthermore, a methodology is presented on associating such information to predict a single anchor's resistance on the basis of sophisticated non‐linear analyses and testing with engineered fibres alignments.
T2 - Annual Meeting of the European-Association-on-Quality-Control-of-Bridges-and-Structures (EUROSTRUCT)
CY - Vienna, Austria
DA - 25.09.2023
KW - Minimally-invasive evaluation
KW - Fastenings
KW - Anchorage to concrete
KW - Steel fibre reinforced concrete
KW - Non-destructive evaluation NDE
KW - Non-destructive testing NDT
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609223
DO - https://doi.org/10.1002/cepa.2115
VL - 69
IS - 5
SP - 1455
EP - 1463
PB - Wiley
AN - OPUS4-60922
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Schmitt, M.
A1 - Casperson, Ralf
A1 - Baensch, F.
A1 - Müller, D.
T1 - Nationale, europäische und internationale Normung in der zerstörungsfreien Prüfung
N2 - Normung und Standardisierung in der zerstörungsfreien Prüfung finden auf nationaler, europäischer und internationaler Ebene statt. Die Übernahme von Leitungsfunktionen in diesen Gremien erzeugt die Möglichkeit der Steuerung von Themen und Inhalten der relevanten Normen. Das persönliche Engagement der Fachexpert*innen in den nationalen Gremien und den europäischen und internationalen Arbeitsgruppen ist ein zusätzlicher Faktor für die inhaltliche Korrektheit und die inhaltliche Ausrichtung der Norm. Denn wer nicht normt, wird genormt und muss letztlich Normen anwenden, die andere entsprechend ihrer eigenen Interessen gestaltet haben. Voraussetzung für die Teilnahme in europäischen und internationalen Normungsgremien ist die Mitwirkung in den entsprechenden DINSpiegelgremien, welche die europäischen (CEN) und internationalen (ISO) Aktivitäten spiegeln und die Fachexpert*innen für die Mitarbeit autorisieren.
Auf internationaler Ebene findet die Normungsarbeit in den technischen Komitees ISO/TC 135 “Non-destructive testing” und ISO/TC 44/SC 5 “Testing and inspection of welds” und ihren Arbeitsgruppen statt. Das europäische Pendant ist das CEN/TC 138 “Zerstörungsfreie Prüfverfahren” mit seinen Arbeitsgremien. Die DINSpiegelgremien sind für die deutsche Mitarbeit in diesen Gremien und die inhaltliche Bewertung der Norm-Entwürfe zuständig.
T2 - DGZfP Jahrestagung 2024
CY - Osnabrück, Germany
DA - 05.05.2024
KW - Normung
KW - Zerstörungsfreie Prüfung
KW - Qualifizierung
KW - Qualitätssicherung
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600726
DO - https://doi.org/10.58286/29496
IS - 5
SP - 1
EP - 6
AN - OPUS4-60072
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Janina
A1 - Kaufmann, Jan Ole
A1 - Weller, Michael G.
T1 - Simple Determination of Affinity Constants of Antibodies by Competitive Immunoassays
N2 - The affinity constant, also known as the equilibrium constant, binding constant, equilibrium association constant, or the reciprocal value, the equilibrium dissociation constant (Kd), can be considered as one of the most important characteristics for any antibody–antigen pair. Many methods based on different technologies have been proposed and used to determine this value. However, since a very large number of publications and commercial datasheets do not include this information, significant obstacles in performing such measurements seem to exist. In other cases where such data are reported, the results have often proved to be unreliable. This situation may indicate that most of the technologies available today require a high level of expertise and effort that does not seem to be available in many laboratories. In this paper, we present a simple approach based on standard immunoassay technology that is easy and quick to perform. It relies on the effect that the molar IC50 approaches the Kd value in the case of infinitely small concentrations of the reagents. A two-dimensional dilution of the reagents leads to an asymptotic convergence to Kd. The approach has some similarity to the well-known checkerboard titration used for the optimization of immunoassays. A well-known antibody against the FLAG peptide, clone M2, was used as a model system and the results were compared with other methods. This approach could be used in any case where a competitive assay is available or can be developed. The determination of an affinity constant should belong to the crucial parameters in any quality control of antibody-related products and assays and should be mandatory in papers using immunochemical protocols.
N2 - Die Affinitätskonstante, auch bekannt als Gleichgewichtskonstante, Bindungskonstante, Gleichgewichtsassoziationskonstante oder der reziproke Wert, die Gleichgewichtsdissoziationskonstante (Kd), kann als eine der wichtigsten Eigenschaften für jedes Antikörper-Antigen-Paar angesehen werden. Zur Bestimmung dieses Wertes wurden zahlreiche Methoden auf der Grundlage verschiedener Technologien vorgeschlagen und verwendet. Da jedoch eine sehr große Anzahl von Veröffentlichungen und kommerziellen Datenblätter diese Information nicht enthalten, scheint es erhebliche Hindernisse bei der Durchführung solcher Messungen zu geben. In anderen Fällen, in denen solche Daten angegeben werden, haben sich die Ergebnisse häufig als unzuverlässig erwiesen. Diese Situation könnte darauf hindeuten, dass die meisten der heute verfügbaren Technologien ein hohes Maß an Fachwissen und Aufwand erfordern, das in vielen Labors nicht vorhanden zu sein scheint. In diesem Beitrag stellen wir einen einfachen Ansatz vor, der auf der Standard-Immunoassay-Technologie basiert und einfach und schnell durchführbar ist. Er beruht auf dem Effekt, dass sich der molare IC50 bei unendlich kleinen Reagenz-Konzentrationen dem Kd-Wert annähert. Eine zweidimensionale Verdünnung der Reagenzien führt zu einer asymptotischen Konvergenz zu Kd. Der Ansatz hat eine gewisse Ähnlichkeit mit der bekannten Checkerboard-Titration, die zur Optimierung von Immunoassays verwendet wird. Ein bekannter Antikörper gegen das FLAG-Peptid, Klon M2, wurde als Modellsystem verwendet, und die Ergebnisse wurden mit anderen Methoden verglichen. Dieser Ansatz kann überall dort angewendet werden, wo ein kompetitiver Assay verfügbar ist oder entwickelt werden kann. Die Bestimmung einer Affinitätskonstante sollte zu den entscheidenden Parametern bei der Qualitätskontrolle von Antikörperprodukten und -assays gehören und in Arbeiten, die immunchemische Protokolle verwenden, obligatorisch sein.
KW - ELISA
KW - Competitive immunoassay
KW - IC50
KW - Test midpoint
KW - Point of inflection
KW - Equilibrium constant
KW - Dissociation constant
KW - Binding strength
KW - Antibody antigen complex
KW - Bio-interaction
KW - SPR
KW - Surface-plasmon resonance
KW - FLAG peptide
KW - Clone M2
KW - Antibody quality
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605607
DO - https://doi.org/10.3390/mps7030049
SN - 2409-9279
VL - 7
IS - 3
SP - 1
EP - 11
PB - MDPI
CY - Basel
AN - OPUS4-60560
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sunder, S.
A1 - Jauregui Rozo, Maria
A1 - Inasu, S.
A1 - Schartel, Bernhard
A1 - Ruckdäschel, H.
T1 - A systematic investigation of the transfer of polyphosphate/inorganic silicate flame retardants from epoxy resins to layered glass fiber-reinforced composites and their post-furnace flexural properties
N2 - The systematic transfer of solvent-free, additive flame retardant (FR) formulations from epoxy resins to glass fiber-reinforced epoxy composites (GFRECs) through prepregs is difficult. Additionally, obtaining data on their post-fire mechanics is often challenging. Utilizing melamine polyphosphate (MPP), ammonium polyphosphate (APP), and silane-coated ammonium polyphosphate (SiAPP) FRs with low-melting inorganic silicates (InSi) in an 8:2 proportion and 10% loading by weight in a diglycidyl ether of bisphenol A (DGEBA) resin, a systematic investigation of the processing properties, room-temperature mechanics, and temperature-based mechanics of the systems was performed. The resin was cured with a dicyandiamide hardener (DICY) and a urone accelerator. The results revealed no substantial impact of these FRs at the current loading on the resin's glass transition temperature or processability. However, the fire residues from cone calorimetry tests of the composites containing FRs were found to be only 15-20% of the thickness of the resins, implying a suppression of intumescence upon transfer. At room temperature, the decrease in the flexural modulus for the composites containing FRs was negligible. Exposure of the composites in a furnace at 400°C as a preliminary study before ignition tests was shown to cause significant flexural moduli reductions after 2.5 min of exposure and complete delamination after 3 min making further testing unviable. This study emphasizes the need for future research on recovering modes of action upon transfer of FR formulations from resins to composites. Based on the challenges outlined in this investigation, sample adaptation methods for post-fire analysis will be developed in a future study.
KW - DGEBA
KW - Prepregs
KW - Glass fiber-reinforced composites
KW - Post-fire testing
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605239
DO - https://doi.org/10.1002/pc.28416
SN - 1548-0569
SN - 0272-8397
VL - 45
IS - 10
SP - 9389
EP - 9406
PB - Wiley
AN - OPUS4-60523
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Simon, Franz-Georg
A1 - Scholz, Philipp
T1 - Sequential Extraction of Incineration Bottom Ash: Conclusions Regarding Ecotoxicity
N2 - The classification of incineration bottom ash (IBA) as hazardous or non-hazardous according to ecotoxic hazard property HP14 is still under debate. In this context, only the compounds of Zn and Cu with the hazard statement code H410 are of relevance. With an approach based on the grouping of substances, it was shown that such substances are either readily water-soluble or slightly and sparingly soluble. The concentrations of readily soluble Cu and Zn compounds in IBA are far below the cut-off value of 0.1%. Slightly and sparingly soluble Zn and Cu compounds could be quantified in the first fraction of a four-step sequential extraction procedure. With the results from the complete sequence, the dimensionless synthesis toxicity index (STI) was calculated and was in the range of 494 to 1218 for the four investigated IBA samples. It was concluded that IBA can usually be classified as non-hazardous.
KW - Incineration bottom ash
KW - Hazard properties
KW - Ecotoxicity
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605262
DO - https://doi.org/10.3390/app14135541
SN - 2076-3417
VL - 14
IS - 13
SP - 1
EP - 12
PB - MDPI
CY - Basel
AN - OPUS4-60526
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rockel, Daniel
A1 - Sanchez Olivares, G.
A1 - Schartel, Bernhard
T1 - Improving the Flame Retardancy of Aluminium Trihydroxide in Thermoplastic Starch Biocomposites Using Waste Fibers and Silicon-Based Synergists
N2 - The synergistic behavior of different silicon compounds is investigated in flame retardant biocomposites with aluminum trihydroxide (ATH) as the main flame retardant. The paper shows a new approach towards sustainable biocomposites through the implementation of thermoplastic starch (TPS), leather fibers from industrial waste streams, and non-hazardous flame retardants and synergists. In these multicomponent systems, the different components address different modes of action in the fire scenario. When ATH is partially substituted by glass frits or layered silicates, fire performance is enhanced without changing the total amount of filler in the polymer. In a biocomposite with 25 phr of fiber and 90 phr of ATH, substituting 5 phr of ATH for layered silicates increased the LOI from 31.5 vol % to 34.8 vol %, decreased the peak of heat release by 20%, and increased the UL 94 rating from V-1 to V-0.
KW - Biocomposites
KW - Sustainability
KW - Waste streams
KW - Flame retardancy
KW - Synergism
KW - Modes of action
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605711
DO - https://doi.org/10.1021/acssusresmgt.4c00053
SN - 2837-1445
VL - 1
IS - 6
SP - 1131
EP - 1145
PB - ACS
AN - OPUS4-60571
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Scales, B. S.
A1 - Hasenrück, C.
A1 - Moldaenke, L.
A1 - Hassa, J.
A1 - Rückert-Reed, C.
A1 - Rummel, C.
A1 - Völkner, C.
A1 - Rynek, R.
A1 - Busche, T.
A1 - Kalinowski, J.
A1 - Jahnke, A.
A1 - Schmitt-Jansen, M.
A1 - Wendt-Potthoff, K.
A1 - Oberbeckmann, Sonja
T1 - Hunting for pigments in bacterial settlers of the Great Pacific Garbage Patch
N2 - The Great Pacific Garbage Patch, a significant collection of plastic introduced by human activities, provides an ideal environment to study bacterial lifestyles on plastic substrates. We proposed that bacteria colonizing the floating plastic debris would develop strategies to deal with the ultravioletexposed substrate, such as the production of antioxidant pigments. We observed a variety of pigmentation in 67 strains that were directly cultivated from plastic pieces sampled from the Garbage Patch. The genomic analysis of four representative strains, each distinct in taxonomy, revealed multiple pathways for carotenoid production. These pathways include those that produce
less common carotenoids and a cluster of photosynthetic genes. This
cluster appears to originate from a potentially new species of the Rhodobacteraceae family. This represents the first report of an aerobic anoxygenic photoheterotrophic bacterium from plastic biofilms. Spectral analysis showed that the bacteria actively produce carotenoids, such as betacarotene and beta-cryptoxanthin, and bacteriochlorophyll a. Furthermore, we discovered that the genetic ability to synthesize carotenoids is more common in plastic biofilms than in the surrounding water communities. Our findings suggest that plastic biofilms could be an overlooked source of bacteria-produced carotenoids, including rare forms. It also suggests that photoreactive molecules might play a crucial role in bacterial biofilm communities in surface water.
KW - Microplastics
KW - Biofilm
KW - Pigment
KW - Microorganisms
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-605725
DO - https://doi.org/10.1111/1462-2920.16639
SN - 1462-2912
VL - 26
IS - 6
SP - e16639
PB - John Wiley & Sons Ltd.
AN - OPUS4-60572
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Baláž, Matej
A1 - Birinci, Mustafa
A1 - Şentürk, Kader
A1 - Achimovičová, Marcela
A1 - Baláž, Peter
A1 - Tampubolon, Imelda Octa
A1 - Stolar, Tomislav
A1 - Bienert, Ralf
A1 - Emmerling, Franziska
A1 - Erdemoğlu, Sema
A1 - Sis, Hikmet
A1 - Erdemoğlu, Murat
T1 - Utilizing Taguchi method and in situ X-ray powder diffraction monitoring to determine the influence of mechanical activation conditions on the physico-chemical properties and Al leachability of K-feldspar
N2 - K-feldspar represents an important natural resource of potassium and aluminum. Within the framework of this study, the K-feldspar was mechanically activated in a planetary ball mill under different conditions planned according to 43 Taguchi orthogonal array experimental design. As outputs, specific surface area (SBET), median particle size (d50), amorphization degree of mineral phases , and Al recovery were used. It was found that the initial d50 value of 293 μm could be reduced to 6.7 μm and the SBET value of 4.7 m2/g could be increased up to 32.5 m2/g upon milling. Both microcline KAl3SiO8, and albite NaAl3SiO8 could be almost completely amorphized, whereas quartz SiO2 still maintained some crystallinity even under the most intensive conditions. Increasing SBET and decreasing the d50 values did not lead to a significant improvement in Al leach recovery, whereas a clear relationship between the amorphization of microcline and the recovered aluminum was found. Analysis of Variance (ANOVA) showed that increasing ball-to-powder ratio is the most beneficial for the improvement in Al recovery. In situ powder X-ray diffraction monitoring performed in an oscillation ball mill under synchrotron irradiation has shown very rapid amorphization of microcline phase at the beginning. However, amorphization of microcline was only partial after two hours of the treatment in this mill, apart from almost complete process in the planetary ball mill. In the end, regressions for the calculation of Al recovery by knowing the values of input parameters were calculated. In general, by just using mechanical activation without the subsequent roasting process that is commonly used to boost metal recoveries, it was possible to quantitatively recover aluminum from K-feldspar.
KW - Mechanochemistry
KW - Mechanical activation
KW - Design of experiments
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611059
DO - https://doi.org/10.1016/j.jmrt.2024.08.156
SN - 2238-7854
VL - 32
SP - 3886
EP - 3895
PB - Elsevier B.V.
AN - OPUS4-61105
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bacurau, V. P.
A1 - Moreira, P. A. F. P.
A1 - Bertoli, G.
A1 - Andreoli, A. F.
A1 - Mazzer, E.
A1 - de Assis, F. F.
A1 - Gargarella, P.
A1 - Koga, G.
A1 - Stumpf, G. C.
A1 - Figueroa, S. J. A.
A1 - Widom, M.
A1 - Kaufman, M.
A1 - Fantin, Andrea
A1 - Cao, Y.
A1 - Freitas, R.
A1 - Miracle, D.
A1 - Coury, F. G.
T1 - Comprehensive analysis of ordering in CoCrNi and CrNi2 alloys
N2 - Chemical Short-Range Order (CSRO) has attracted recent attention from many researchers, creating intense debates about its impact on material properties.
The challenges lie in confirming and quantifying CSRO, as its detection proves exceptionally demanding, contributing to conflicting data in the literature regarding its true effects on mechanical properties. Our work uses highprecision calorimetric data to unambiguously prove the existence and, coupled with atomistic simulations, quantify the type of CSRO. This methodology allows us to propose a mechanism for its formation and destruction based on the heat evolution during thermal analysis and facilitates a precise identification of local ordering in CoCrNi alloys. Samples of CoCrNi (Co33Cr33Ni33) and CrNi2 (Cr33Ni66) alloys are fabricated in varying ordered states, extensively characterized via synchrotron X-ray diffraction, X-ray absorption spectroscopy, and transmission electron microscopy. Samples with considerably different ordered states are submitted to tensile tests with in-situ synchrotron X-ray diffraction. We demonstrate, despite inducing varied CSRO levels in CoCrNi, no significant alterations in overall mechanical behavior emerge.
However, the CrNi2 alloy, which undergoes long-range ordering, experiences significant shifts in yield strength, ultimate tensile stress and ductility.
KW - Mechanical properties
KW - Short-range ordering
KW - Calorimetry
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611075
DO - https://doi.org/10.1038/s41467-024-52018-w
VL - 15
IS - 1
SP - 1
EP - 11
PB - Springer Science and Business Media LLC
AN - OPUS4-61107
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Simon, Fabian
A1 - von der Au, Marcus
A1 - Gehrenkemper, Lennart
A1 - Meermann, Björn
T1 - An optimized method for PFAS analysis using HR–CS–GFMAS via GaF detection
N2 - The analysis of per- and polyfluoroalkyl substances (PFAS) via sum parameters like extractable organic fluorine (EOF) in combination with high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR–CS–GFMAS) is highly promising regarding fluorine sensitivity and selectivity. However, the HR–CS–GFMAS method includes several drying and heating steps which can lead to losses of volatile PFAS before the molecular formation step using e.g., GaF formation. Hence, the method leads to a strong discrimination of PFAS within the EOF depending on their physical/chemical properties and is therefore associated with reduced accuracy. To reduce this discrepancy and to indicate realistic PFAS pollution values, an optimization of the HR–CS–GFMAS method for PFAS analysis is needed. Hence, we determined fluorine response factors of several PFAS with different physical/chemical properties upon application of systematic optimization steps. We could therefore improve the method's sensitivity for PFAS analysis using a modifier drying pre-treatment step followed by a sequential injection of sample solutions. The highest improvement in sensitivity of volatile PFAS was shown upon addition of a Mg modifier during drying pre-treatment. Thereby, during optimization the relative standard deviation of fluorine response factors could be reduced from 55 % (initial method) to 27 % (optimized method) leading to a more accurate determination of organofluorine sum parameters. The method provides an instrumental LOD and LOQ of β(F) 1.71 μg/L and 5.13 μg/L, respectively. Further validation aimed to investigate several matrix effects with respect to water matrices. Here, substance-specific behavior was observed. For example, perfluorooctanoic acid (PFOA) which was used as calibrator, showed signal suppressions upon high chloride concentrations (>50 mg/L). Hence, a thorough separation of Cl from analytes during sample preparation is needed for accurate sum parameter analysis.
KW - PFAS
KW - GF-AAS
KW - Method optimization
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610522
DO - https://doi.org/10.1016/j.talanta.2024.126811
VL - 281
SP - 1
EP - 11
PB - Elsevier B.V.
AN - OPUS4-61052
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chronakis, Michail Ioannis
A1 - Meermann, Björn
A1 - von der Au, Marcus
T1 - The evolution of data treatment tools in single-particle and single-cell ICP-MS analytics
N2 - Single-particle inductively coupled plasma-mass spectrometry (sp-ICP-MS) is one of the most powerful tools in the thriving field of nanomaterial analysis. Along the same lines, single-cell ICP-MS (sc-ICP-MS) has become an invaluable tool in the study of the variances of cell populations down to a per-cell basis. Their importance and application fields have been listed numerous times, across various reports and reviews. However, not enough attention has been paid to the immense and ongoing development of the tools that are currently available to the analytical community for the acquisition, and more importantly, the treatment of single-particle and single-cell-related data. Due to the ever-increasing demands of modern research, the efficient and dependable treatment of the data has become more important than ever. In addition, the field of single-particle and single-cell analysis suffers due to a large number of approaches for the generated data—with varying levels of specificity and applicability. As a result, finding the appropriate tool or approach, or even comparing results, can be challenging. This article will attempt to bridge these gaps, by covering the evolution and current state of the tools at the disposal of sp-ICP-MS users.
Graphical Abstract
KW - Trend Article
KW - spICP-MS
KW - Data Tools
KW - scICP-MS
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610539
DO - https://doi.org/10.1007/s00216-024-05513-4
SP - 1
EP - 7
PB - Springer Science and Business Media LLC
AN - OPUS4-61053
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mangarova, Dilyana Branimirova
A1 - Reimann, Carolin
A1 - Kaufmann, Jan Ole
A1 - Möckel, Jana
A1 - Kader, Avan
A1 - Adams, Lisa Christine
A1 - Ludwig, Antje
A1 - Onthank, David
A1 - Robinson, Simon
A1 - Karst, Uwe
A1 - Helmer, Rebecca
A1 - Botnar, Rene
A1 - Hamm, Bernd
A1 - Makowski, Marcus Richard
A1 - Brangsch, Julia
T1 - Elastin-specific MR probe for visualization and evaluation of an interleukin-1β targeted therapy for atherosclerosis
N2 - Atherosclerosis is a chronic inflammatory condition of the arteries and represents the primary cause of various cardiovascular diseases. Despite ongoing progress, finding effective anti-inflammatory therapeutic strategies for atherosclerosis remains a challenge. Here, we assessed the potential of molecular magnetic resonance imaging (MRI) to visualize the effects of 01BSUR, an anti-interleukin-1β monoclonal antibody, for treating atherosclerosis in a murine model. Male apolipoprotein E-deficient mice were divided into a therapy group (01BSUR, 2 × 0.3 mg/kg subcutaneously, n = 10) and control group (no treatment, n = 10) and received a high-fat diet for eight weeks. The plaque burden was assessed using an elastin-targeted gadolinium-based contrast probe (0.2 mmol/kg intravenously) on a 3 T MRI scanner. T1-weighted imaging showed a significantly lower contrast-to-noise (CNR) ratio in the 01BSUR group (pre: 3.93042664; post: 8.4007067) compared to the control group (pre: 3.70679168; post: 13.2982156) following administration of the elastin-specific MRI probe (p < 0.05). Histological examinations demonstrated a significant reduction in plaque size (p < 0.05) and a significant decrease in plaque elastin content (p < 0.05) in the treatment group compared to control animals. This study demonstrated that 01BSUR hinders the progression of atherosclerosis in a mouse model. Using an elastin-targeted MRI probe, we could quantify these therapeutic effects in MRI.
N2 - Atherosklerose ist eine chronische entzündliche Erkrankung der Arterien und die Hauptursache für verschiedene Herz-Kreislauf-Erkrankungen. Trotz kontinuierlicher Fortschritte ist es nach wie vor schwierig, wirksame entzündungshemmende Therapiestrategien für Atherosklerose zu finden. In dieser Studie haben wir das Potenzial der molekularen Magnetresonanztomographie (MRT) zur Visualisierung der Wirkung von 01BSUR, einem monoklonalen Anti-Interleukin-1β-Antikörper, zur Behandlung von Atherosklerose in einem Mausmodell untersucht. Männliche Apolipoprotein-E-defiziente Mäuse wurden in eine Therapiegruppe (01BSUR, 2 × 0,3 mg/kg subkutan, n = 10) und eine Kontrollgruppe (keine Behandlung, n = 10) aufgeteilt und erhielten acht Wochen lang eine fettreiche Diät. Die Plaquebelastung wurde mit einer auf Elastin ausgerichteten Kontrastmittelsonde auf Gadoliniumbasis (0,2 mmol/kg intravenös) auf einem 3-T-MRT-Scanner untersucht. Die T1-gewichtete Bildgebung zeigte ein signifikant niedrigeres Kontrast-Rausch-Verhältnis (CNR) in der 01BSUR-Gruppe (vorher: 3,93042664; nachher: 8,4007067) im Vergleich zur Kontrollgruppe (vorher: 3,70679168; nachher: 13,2982156) nach Verabreichung der Elastin-spezifischen MRT-Sonde (p < 0,05). Histologische Untersuchungen zeigten eine signifikante Verringerung der Plaque-Größe (p < 0,05) und eine signifikante Abnahme des Plaque-Elastin-Gehalts (p < 0,05) in der Behandlungsgruppe im Vergleich zu den Kontrolltieren. Diese Studie zeigte, dass 01BSUR das Fortschreiten der Atherosklerose in einem Mausmodell hemmt. Mit einer auf Elastin ausgerichteten MRT-Sonde konnten wir diese therapeutischen Effekte in der MRT quantifizieren.
KW - Atherosclerosis
KW - Molecular imaging
KW - Elastin
KW - Plaque
KW - Interleukin-1beta
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610858
DO - https://doi.org/10.1038/s41598-024-71716-5
VL - 14
IS - 1
SP - 1
EP - 11
PB - Springer Science and Business Media LLC
AN - OPUS4-61085
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sunder, S.
A1 - Jauregui Rozo, Maria
A1 - Inasu, S.
A1 - Schartel, Bernhard
A1 - Ruckdäschel, H.
T1 - Investigating the changing dynamics of processing, temperature-based mechanics, and flame retardancy in the transfer of ammonium polyphosphate/inorganic silicate flame retardants from epoxy resins to glass fiber composites
N2 - Although numerous investigations study the improvement of flame retardancy of epoxy resins using additives, maintaining the flame retardant (FRs) modes of action present in the resins upon transfer to composites is challenging. In this study, ammonium polyphosphate (APP) and inorganic silicate (InSi) are loaded at 10%, 30%, and 50% by weight, in a diglycidyl ether of bisphenol A (DGEBA) resin cured with dicyandiamide and transferred to bidirectional (BD) glass fiber (GF) composites. Although a 50% loading of the FRs impacts the curing kinetics of the resin system, the effect on the glass transition temperature of the resin system remains negligible compared to reactive FRs in the state of the art integrated into the resin's chemical structure. Increasing the FR content improved the heat release characteristics in both the resins and composites. However, the charring mode of action is completely suppressed in the formulation with 10% APP + InSi. A 30% concentration of the FRs restored the charring action in the composite and the GFs provide increased protective layer action upon transfer to the composites. This study highlights the importance of accounting for the changing dynamics related to processing and flame retardancy upon transferring FRs from resins to composites.
KW - Composites
KW - Flame retardance
KW - Resins
KW - Synthesis and processing techniques
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-610484
DO - https://doi.org/10.1002/app.55988
SN - 1097-4628
VL - 141
IS - 39
SP - 1
EP - 18
PB - Wiley
CY - New York, NY
AN - OPUS4-61048
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Golian, M. J.
A1 - Friedman, D. A.
A1 - Harrison, M.
A1 - McMahon, Dino Peter
A1 - Buellesbach, J.
T1 - Chemical and transcriptomic diversity do not correlate with ascending levels of social complexity in the insect order Blattodea
N2 - AbstractEusocial insects, such as ants and termites, are characterized by high levels of coordinated social organization. This is contrasted by solitary insects that display more limited forms of collective behavior. It has been hypothesized that this gradient in sociobehavioral sophistication is positively correlated with chemical profile complexity, due to a potentially increased demand for diversity in chemical communication mechanisms in insects with higher levels of social complexity. However, this claim has rarely been assessed empirically. Here, we compare different levels of chemical and transcriptomic complexity in selected species of the order Blattodea that represent different levels of social organization, from solitary to eusocial. We primarily focus on cuticular hydrocarbon (CHC) complexity, since it has repeatedly been demonstrated that CHCs are key signaling molecules conveying a wide variety of chemical information in solitary as well as eusocial insects. We assessed CHC complexity and divergence between our studied taxa of different social complexity levels as well as the differentiation of their respective repertoires of CHC biosynthesis gene transcripts. Surprisingly, we did not find any consistent pattern of chemical complexity correlating with social complexity, nor did the overall chemical divergence or transcriptomic repertoire of CHC biosynthesis genes reflect on the levels of social organization. Our results challenge the assumption that increasing social complexity is generally reflected in more complex chemical profiles and point toward the need for a more cautious and differentiated view on correlating complexity on a chemical, genetic, and social level.
KW - Chemical ecology
KW - Ecological genetics
KW - Entomology
KW - Evolutionary ecology
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608260
DO - https://doi.org/10.1002/ece3.70063
SN - 2045-7758
VL - 14
IS - 8
SP - 1
EP - 13
PB - Wiley
AN - OPUS4-60826
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hellemans, S.
A1 - Rocha, M. M.
A1 - Wang, M.
A1 - Romero Arias, J.
A1 - Aanen, D. K.
A1 - Bagnères, A.-G.
A1 - Buček, A.
A1 - Carrijo, T. F.
A1 - Chouvenc, T.
A1 - Cuezzo, C.
A1 - Constantini, J. P.
A1 - Constantino, R.
A1 - Dedeine, F.
A1 - Deligne, J.
A1 - Eggleton, P.
A1 - Evans, T. A.
A1 - Hanus, R.
A1 - Harrison, Mark C.
A1 - Harry, M.
A1 - Josens, G.
A1 - Jouault, C.
A1 - Kalleshwaraswamy, C. M.
A1 - Kaymak, E.
A1 - Korb, J.
A1 - Lee, C.-Y.
A1 - Legendre, F.
A1 - Li, H.-F.
A1 - Lo, N.
A1 - Lu, T.
A1 - Matsuura, K.
A1 - Maekawa, K.
A1 - McMahon, Dino Peter
A1 - Mizumoto, N.
A1 - Oliveira, D. E.
A1 - Poulsen, M.
A1 - Sillam-Dussès, D.
A1 - Su, N.-Y.
A1 - Tokuda, G.
A1 - Vargo, E. L.
A1 - Ware, J. L.
A1 - Šobotník, J.
A1 - Scheffrahn, R. H.
A1 - Cancello, E.
A1 - Roisin, Y.
A1 - Engel, M. S.
A1 - Bourguignon, T.
T1 - Genomic data provide insights into the classification of extant termites
N2 - The higher classification of termites requires substantial revision as the Neoisoptera, the most diverse termite lineage, comprise many paraphyletic and polyphyletic higher taxa. Here, we produce an updated termite classification using genomic-scale analyses. We reconstruct phylogenies under diverse substitution models with ultraconserved elements analyzed as concatenated matrices or within the multi-species coalescence framework. Our classification is further supported by analyses controlling for rogue loci and taxa, and topological tests. We show that the Neoisoptera are composed of seven family-level monophyletic lineages, including the Heterotermitidae Froggatt, Psammotermitidae Holmgren, and Termitogetonidae Holmgren, raised from subfamilial rank. The species-rich Termitidae are composed of 18 subfamily-level monophyletic lineages, including the new subfamilies Crepititermitinae, Cylindrotermitinae, Forficulitermitinae, Neocapritermitinae, Protohamitermitinae, and Promirotermitinae; and the revived Amitermitinae Kemner, Microcerotermitinae Holmgren, and Mirocapritermitinae Kemner. Building an updated taxonomic classification on the foundation of unambiguously supported monophyletic lineages makes it highly resilient to potential destabilization caused by the future availability of novel phylogenetic markers and methods. The taxonomic stability is further guaranteed by the modularity of the new termite classification, designed to accommodate as-yet undescribed species with uncertain affinities to the herein delimited monophyletic lineages in the form of new families or subfamilies.
KW - Termite
KW - Taxonomy
KW - Evolution
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608276
DO - https://doi.org/10.1038/s41467-024-51028-y
VL - 15
IS - 1
SP - 1
EP - 17
PB - Springer Science and Business Media LLC
AN - OPUS4-60827
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - El Moutaouakil, H.
A1 - Fuchs, C.
A1 - Savli, E.
A1 - Heimann, Jan
A1 - Prager, Jens
A1 - Moll, J.
A1 - Tschöke, K.
A1 - Márquez Reyes, O.
A1 - Schackmann, O.
A1 - Memmolo, V.
A1 - Schneider, T.
T1 - Acquiring a Machine Learning Data Set for Structural Health Monitoring of Hydrogen Pressure Vessels at Operating Conditions using Guided Ultrasonic Waves
N2 - Hydrogen is an energy source of increasing importance. As hydrogen is very reactive to air and needs to be stored under high pressure, it is crucial to provide safe transportation and storage. Therefore, structural health monitoring, based on guided ultrasonic waves and machine learning methods, is used for Composite Overwrapped Pressure Vessels (COPVs) containing hydrogen. To acquire data that allows robust detection of COPV defects, there are two main process parameters to consider. These are the pressurization of the vessel and the temperature conditions at the vessel. This paper will focus on the derivation of a design of experiment (DoE) from the needs of various validation scenarios (e.g. concerning pressure, temperature or excitation frequency). Practical limitations must be considered as well. We designed experiments with multiple reversible damages at different positions. A network of 25 transducers, structured as five rings with five sensors in one line, is installed on a vessel. Guided ultrasonic waves are used via the pitch-catch procedure, which means that the transducers act pairwise as transmitter and receiver in order to measure all transmitterreceiver combinations. This leads to 600 signal paths, recorded by a Verasonics Vantage 64 LF data acquisition system. Finally, the influences of temperature and pressure within the acquired data set are going to be visualized.
T2 - 11th European Workshop on Structural Health Monitoring
CY - Potsdam, Germany
DA - 10.06.2024
KW - Composite Overwrapped Pressure Vessel
KW - Hydrogen
KW - Guided Ultrasonic Waves
KW - Data Acquisition
KW - Pressurization
KW - Machine Learning
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-607472
DO - https://doi.org/10.58286/29754
SN - 1435-4934
SP - 1
EP - 8
AN - OPUS4-60747
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kadri, Lena
A1 - Casali, Lucia
A1 - Emmerling, Franziska
A1 - Tajber, Lidia
T1 - Mechanochemical comparison of ball milling processes for levofloxacin amorphous polymeric systems
N2 - This study aimed to investigate the amorphization capabilities of levofloxacin hemihydrate (LVXh), a fluoroquinolone drug, using a polymer excipient, Eudragit® L100 (EL100). Ball milling (BMing) was chosen as the manufacturing process and multiple mill types were utilized for comparison purposes. The product outcomes of each mill were analyzed in detail. The solid-state of the samples produced was comprehensively characterized by Powder X-ray Diffraction (PXRD), In-situ PXRD, Differential Scanning Calorimetry (DSC), Solid-State Fourier Transform Infrared Spectroscopy (FT-IR), and Dynamic Vapor Sorption (DVS). The crystallographic planes of LVXh were investigated by in-situ PXRD to disclose the presence or absence of weak crystallographic plane(s). The mechanism of LVXh:EL100 system formation was discovered as a two-step process, first involving amorphization of LVXh followed by an interaction with EL100, rather than as an instantaneous process. DVS studies of LVXh:EL100 samples showed different stability properties depending on the mill used and % LVXh present. Overall, a more sustainable approach for achieving full amorphization of the fluoroquinolone drug, LVXh, was accomplished, and advancements to the fast-growing world of pharmaceutical mechano- and tribo-chemistry were made.
KW - Levofloxacin
KW - Eudragit® L100
KW - Mechanochemistry
KW - Phase transformation
KW - In situ monitoring
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611129
DO - https://doi.org/10.1016/j.ijpharm.2024.124652
SN - 0378-5173
VL - 665
SP - 1
EP - 16
PB - Elsevier B.V.
AN - OPUS4-61112
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schneider, Beate
A1 - Pfeiffer, Friedhelm
A1 - Remus, Daniela
A1 - Dyall-Smith, Mike
A1 - Kunte, Hans-Jörg
ED - Klepac-Ceraj, Vanja
T1 - Genome sequence of Pseudomonas silesiensis strain G3, a member of a bacterial consortium capable of polyethylene degradation
N2 - A consortium of landfill bacteria including strain G3 can break down polyethylene, a long-lasting plastic that accumulates in the environment. The complete genome sequence of strain G3 was determined by PacBio and Nanopore sequencing and consists of three circular replicons. Genome-based classification assigned strain G3 to the species Pseudomonas silesiensis.
KW - PE degradation
KW - Polyethylene
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-611618
DO - https://doi.org/10.1128/mra.00138-24
SN - 2576-098X
VL - 13
IS - 11
SP - 1
EP - 3
PB - American Society for Microbiology
AN - OPUS4-61161
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Jasiuniene, E.
A1 - Yilmaz, Bengisu
A1 - Smagulova, D.
A1 - Bhat, G. A.
A1 - Cicenas, V.
A1 - Zukauskas, E.
A1 - Mazeika, L.
T1 - Non-Destructive Evaluation of the Quality of Adhesive Joints Using Ultrasound, X-ray, and Feature-Based Data Fusion
N2 - The aim of this work is to achieve reliable nondestructive evaluation (NDE) of adhesively bonded aerospace components by developing novel multidimensional data fusion techniques, which would combine the information obtained by ultrasonic and X-ray NDE methods. Separately, both NDE techniques have their advantages and limitations. The integration of data obtained from pulse echo immersion ultrasound testing and radiography holds immense potential to help improve the reliability of non-destructive evaluation. In this study, distinctive features obtained from single techniques, traditional ultrasonic pulse echo testing, and radiography, as well as fused images, were investigated and the suitability of these distinctive features and fusion techniques for improving the probability of defect detection was evaluated. For this purpose, aluminum single lap joints with brass inclusions were analyzed using ultrasound pulse echo and radiography techniques. The distinctive features were extracted from the data obtained, and images of features obtained by both techniques were fused together. Different combinations of features and fusion algorithms were investigated, considering the desire to automate data evaluation in the future.
KW - Data fusion
KW - Ultrasonics
KW - Radiography
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565789
DO - https://doi.org/10.3390/app122412930
VL - 12
IS - 24
SP - 1
EP - 20
PB - MDPI
AN - OPUS4-56578
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dariz, P.
A1 - Schmid, Thomas
T1 - Raman focal point on Roman Egyptian blue elucidates disordered cuprorivaite, green glass phase and trace compounds
N2 - The discussed comparative analyses of Roman Imperial pigment balls and fragmentary murals unearthed in the ancient cities of Aventicum and Augusta Raurica (Switzerland) by means of Raman microspectroscopy pertain to a predecessor study on trace compounds in Early Medieval Egyptian blue (St. Peter, Gratsch, South Tyrol, Northern Italy). The plethora of newly detected associated minerals of the raw materials surviving the synthesis procedure validate the use of quartz sand matching the composition of sediments transported by the Volturno river into the Gulf of Gaeta (Campania, Southern Italy) with a roasted sulphidic copper ore and a mixed-alkaline plant ash as fluxing agent. Thus, the results corroborate a monopolised pigment production site located in the northern Phlegrean Fields persisting over the first centuries A.D., this in line with statements of the antique Roman writers Vitruvius and Pliny the Elder and recent archaeological evidences. Beyond that, Raman spectra reveal through gradual peak shifts and changes of band width locally divergent process conditions and compositional inhomogeneities provoking crystal lattice disorder in the chromophoric cuprorivaite as well as the formation of a copper-bearing green glass phase, the latter probably in dependency of the concentration of alkali flux, notwithstanding that otherwise solid-state reactions predominate the synthesis.
KW - Raman microspectroscopy
KW - Egyptian blue
KW - Cuprorivaite
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559028
DO - https://doi.org/10.1038/s41598-022-19923-w
SN - 2045-2322
VL - 12
IS - 1
SP - 1
EP - 12
PB - Nature Publishing Group
CY - London
AN - OPUS4-55902
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sechi, R.
A1 - Fackeldey, K.
A1 - Chewle, Surahit
A1 - Weber, M.
T1 - SepFree NMF: A toolbox for analyzing the kinetics of sequential spectroscopic data
N2 - This work addresses the problem of determining the number of components from sequential spectroscopic data analyzed by non-negative matrix factorization without separability assumption (SepFree NMF). These data are stored in a matrix M of dimension “measured times” versus “measured wavenumbers” and can be decomposed to obtain the spectral fingerprints of the states and their evolution over time. SepFree NMF assumes a memoryless (Markovian) process to underline the dynamics and decomposes M so that M = WH, with W representing the components’ fingerprints and H their kinetics. However, the rank of this decomposition (i.e., the number of physical states in the process) has to be guessed from pre-existing knowledge on the observed process. We propose a measure for determining the number of components with the computation of the minimal memory effect resulting from the decomposition; by quantifying how much the obtained factorization is deviating from the Markovian property, we are able to score factorizations of a different number of components. In this way, we estimate the number of different entities which contribute to the observed system, and we can extract kinetic information without knowing the characteristic spectra of the single components. This manuscript provides the mathematical background as well as an analysis of computer generated and experimental sequentially measured Raman spectra.
KW - Kinetics from experiments
KW - Separability assumption
KW - Sequential spectroscopic data
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559046
DO - https://doi.org/10.3390/a15090297
SN - 1999-4893
VL - 15
IS - 9
SP - 1
EP - 16
PB - MDPI
CY - Basel
AN - OPUS4-55904
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fackeldey, K.
A1 - Röhm, J.
A1 - Niknejad, A.
A1 - Chewle, Surahit
A1 - Weber, M.
T1 - Analyzing Raman spectral data without separabiliy assumption
N2 - Raman spectroscopy is a well established tool for the analysis of vibration spectra, which then allow for the determination of individual substances in a chemical sample, or for their phase transitions. In the time-resolved-Raman-sprectroscopy the vibration spectra of a chemical sample are recorded sequentially over a time interval, such that conclusions for intermediate products (transients) can be drawn within a chemical process. The observed data-matrix M from a Raman spectroscopy can be regarded as a matrix product of two unknown matrices W and H, where the first is representing the contribution of the spectra and the latter represents the chemical spectra. One approach for obtaining W and H is the non-negative matrix factorization. We propose a novel approach, which does not need the commonly used separability assumption. The performance of this approach is shown on a real world chemical example.
KW - Non-negative matrix factorization
KW - NMF
KW - Raman spectra
KW - Separability condition
KW - PCCA+
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559051
DO - https://doi.org/10.1007/s10910-020-01201-7
SN - 1572-8897
VL - 59
SP - 575
EP - 596
PB - Springer Science + Business Media
CY - Dordrecht
AN - OPUS4-55905
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schoknecht, Ute
A1 - Mathies, H.
T1 - The Impact of Weather Conditions on Biocides in Paints
N2 - Weather conditions affect biocides on exposed outer surfaces on constructions. Contact with water causes hydrolysis and leaching of substances. Ultraviolet radiation may induce photolysis. As a result, a mixture of biocidal active substances and transformation products can be emitted into the environment. In a semi-field study, leaching of the biocidal active substances terbutryn, diuron, octylisothiazolinone, carbendazim, and selected transformation products was observed for two paints containing either a white or a red pigment. Painted test panels were exposed to natural weathering for about 1.5 years. Runoff samples were analyzed during the course of the experiment.
At the end of the study, residues of biocidal active substances and transformation products were determined in sections of the test panels. Emissions of substances were mainly observed during the first few months of the experiments. Increased emissions of transformation products were observed during periods of increased global radiation and subsequent periods with relatively high amounts of driving rain. Different patterns of transformation products were observed, especially for terbutryn, both for paints containing different pigments and in experiments that were started in different periods of the year, as well as during different periods of the experiments.
KW - Substance release
KW - Construction products
KW - Biocides
KW - Transformation
KW - Weathering
KW - Driving rain
KW - Global radiation
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-560651
DO - https://doi.org/10.3390/ma15207368
VL - 15
IS - 20
SP - 1
EP - 16
PB - MDPI
CY - Basel
AN - OPUS4-56065
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Costabel, S.
A1 - Hiller, Thomas
A1 - Dlugosch, R.
A1 - Kruschwitz, Sabine
A1 - Müller Petke, M.
T1 - Evaluation of single-sided nuclear magnetic resonance technology for usage in geosciences
N2 - Because of its mobility and ability to investigate exposed surfaces, single-sided (SiS) nuclear magnetic resonance (NMR) technology enables new application fields in geosciences. To test and assess its corresponding potential, we compare longitudinal (T1) and transverse (T2) data measured by SiS NMR with those of conventional geoscientific laboratory NMR. We use reference sandstone samples covering a broad range of pore sizes. Our study demonstrates that the lower signal-to-noise ratio of SiS NMR data generally tends to slightly overestimated widths of relaxation time distributions and consequently pore size distributions. While SiS and conventional NMR produce very similar T1 relaxation data, unbiased SiS NMR results for T2 measurements can only be expected for fine material, i.e. clayey or silty sediments and soils with main relaxation times below 0.05s. This limit is given by the diffusion relaxation rate due to the gradient in the primary magnetic field associated with the SiS NMR. Above that limit, i.e. for coarse material, the relaxation data is strongly attenuated. If considering the diffusion relaxation time of 0.2 s in the numerical data inversion process, the information content >0.2s is blurred over a range larger than that of conventional NMR. However, our results show that principle range and magnitudes of the relaxation time distributions are reconstructed to some extent. Regarding these findings, SiS NMR can be helpful to solve geoscientific issues, e.g. to assess the hydro-mechanical properties of the walls of underground facilities or to provide local soil moisture data sets for calibrating indirect remote techniques on the regional scale. The greatest opportunity provided by the SiS NMR technology is the acquisition of profile relaxation data for rocks with significant bedding structures at the µm scale. With this unique feature, SiS NMR can support the understanding and modeling of hydraulic and diffusional anisotropy behavior of sedimentary rocks.
KW - Single-sided NMR
KW - Geosciences
KW - Nuclear magnetic resonance
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561676
DO - https://doi.org/10.1088/1361-6501/ac9800
SN - 0957-0233
VL - 34
IS - 1
SP - 1
EP - 13
PB - IOP Publishing
AN - OPUS4-56167
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ermilova, Elena
A1 - Weise, Matthias
A1 - Hertwig, Andreas
T1 - Hybrid optical measurement technique for detection of defects in epitaxially grown 4H-SiC layers
N2 - Recent developments in power electronics require the use of new wide bandgap compound semiconductor. We demonstrate the use of the ellipsometry and white light interference microscopy to detect defects in epitaxially grown SiC layers on SiC substrates. Such hybrid optical metrology methods can be used to better understand the mechanism of the development of the defects as well as their effects on the material´s optoelectronic properties.
T2 - EOS Annual Meeting (EOSAM 2022)
CY - Porto, Portugal
DA - 12.09.2022
KW - Imaging ellipsometry
KW - White light interference microscopy
KW - Wide bandgap compound semiconductor
KW - Epitaxially grown 4H-SiC layers
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561113
DO - https://doi.org/10.1051/epjconf/202226610001
VL - 266
SP - 1
EP - 2
AN - OPUS4-56111
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Shaheen, Sabahat
A1 - Hicke, Konstantin
T1 - Measurement of Geometric Phase using a φ-OTDR setup
N2 - Geometric phase showing sensitivity to changes in polarisation state and intensity of backscattered light is measured using a novel φ-OTDR setup based on coherent heterodyne detection. Principle is demonstrated using a polarisation scrambler inline a fiber-under-test.
T2 - Optical Fiber Sensors 2022
CY - Alexandria, Virginia, United States
DA - 29.08.2022
KW - Coherent Heterodyne
KW - Geometric Phase
KW - Distributed Fiber Optic Sensor
PY - 2022
SN - 978-1-957171-14-2
SP - W4.72
AN - OPUS4-56116
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sieber, M. J.
A1 - Wilke, M.
A1 - Appelt, O.
A1 - Oelze, Marcus
A1 - Koch-Müller, M.
T1 - Melting relations of Ca–Mg carbonates and trace element signature of carbonate melts up to 9 GPa – A proxy for melting of carbonated mantle lithologies
N2 - The most profound consequences of the presence of Ca–Mg carbonates (CaCO3–MgCO3) in the Earth’s upper mantle may be to lower the melting temperatures of the mantle and control the melt composition.
Low-degree partial melting of a carbonate-bearing mantle produces CO2-rich, silica-poor melts compositionally imposed by the melting relations of carbonates. Thus, understanding the melting relations in the CaCO3–MgCO3 system facilitates the interpretation of natural carbonate-bearing silicate systems.
We report the melting relations of the CaCO3–MgCO3 system and the partition coefficient of trace elements between carbonates and carbonate melt from experiments at high pressure (6 and 9 GPa) and temperature (1300–1800 ◦C) using a rocking multi-anvil press. In the absence of water, Ca–Mg carbonates are stable along geothermal gradients typical of subducting slabs. Ca–Mg carbonates (∼ Mg0.1–0.9Ca0.9–0.1CO3) partially melt beneath mid-ocean ridges and in plume settings. Ca–Mg carbonates melt incongruently, forming periclase crystals and carbonate melt between 4 and 9 GPa. Furthermore, we show that the rare earth element (REE) signature of Group-I kimberlites, namely strong REE fractionation and depletion of heavy REE relative to the primitive mantle, is resembled by carbonate melt in equilibrium with Ca-bearing magnesite and periclase at 6 and 9 GPa. This suggests that the dolomite–magnesite join of the CaCO3–MgCO3 system might be useful to approximate the REE signature of carbonate-rich melts parental to kimberlites.
KW - High pressure experiments
KW - Laser Ablation
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561197
DO - https://doi.org/10.5194/ejm-34-411-2022
SN - 0935-1221
VL - 34
IS - 5
SP - 411
EP - 424
PB - Copernicus Publications
CY - Göttingen
AN - OPUS4-56119
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Ewert, U.
A1 - Jaenisch, Gerd-Rüdiger
A1 - Schumacher, David
A1 - Bircher, B.
A1 - Meli, F.
A1 - Deresch, A.
T1 - EMPIR-Projekt NanoXSpot: Neue Normentwürfe für die Brennfleckmessung an Röntgenröhren im Makro-, Mikro- und Nanometerbereich für Hersteller und Anwender
N2 - Im Rahmen des EMPIR-Projektes NanoXSpot (Nanometre X-ray Focal Spot Measurement) werden rückführbare Messverfahren zur Bestimmung der Brennfleckgröße und -form von Röntgenröhren im Bereich von 100 nm bis 10 mm entwickelt, welche die Grundlage für die Erarbeitung mehrerer Normentwürfe bilden. Diese werden 2022 parallel bei ISO TC 135 (NDT) SC 5 (RT) und CEN TC 138 (NDT) WG 1 (RT) eingereicht. Entsprechende Normen werden auch bei ASTM vorgestellt. Die Norm EN 12543-4 (Kantenmethode) wird umgeschrieben für die Messung von Brennflecken von 1 μm – 10 mm durch Auswertung von Loch- oder Scheibenaufnahmen. Der im Rahmen des NanoXSpot-Projektes neu entwickelte NxS-Testkörper ist geeignet für den Bereich von 1 μm – 100 μm. Von 100 μm bis 10 mm können ASTM-Lochtestkörper verwendet werden, die bereits bei ASTM E 1165 beschrieben sind. Neu ist die Anwendung eines CT-Algorithmus zur Rekonstruktion der Brennflecke, um Lochblenden-basierte Brennfleckkameras, insbesondere im Bereich unter 100 μm, zu ersetzen. Ein neuer Normteil, EN 12543-6, wurde entworfen, um die Brennfleckmessung im Bereich 100 nm – 20 μm mit hoher Genauigkeit zu ermöglichen.
Verschiedene Strichgruppen-Testkörper kommen hier zum Einsatz. Das sind die JIMAPrüfkörper, ein neuer Hochkontrast-Strichgruppentestkörper von YXLON (HiCo) und der neu entwickelte Testkörper NxS. Diese werden vorgestellt. Die Messprozedur für Röhrenhersteller wird auf einer numerischen Fit-Prozedur basieren, die über einen Ringversuch im Projekt validiert wurde. Beide Normen benötigen numerische Auswertealgorithmen zur korrekten Anwendung, die als kommerzielle Software und Public Domain – Software verfügbar gemacht werden. Es wird über die zu erwartenden Standardprozeduren und die erforderliche Hardware zur Anwendung der Normen informiert.
T2 - DGZfP-Jahrestagung
CY - Kassel, Germany
DA - 23.05.2022
KW - Röntgenröhre
KW - Brennfleckmessung
KW - Normung
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561029
SP - 1
EP - 10
AN - OPUS4-56102
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - CONF
A1 - Schumacher, David
A1 - Jaenisch, Gerd-Rüdiger
A1 - Ewert, U.
A1 - Bircher, B.
A1 - Meli, F.
A1 - Sofiienko, A.
A1 - Steffen, J. P.
A1 - Deresch, A.
T1 - EMPIR-Projekt NanoXSpot: Ringversuch zur Untersuchung der neu entwickelten Methoden für die Brennfleckmessung an Röntgenröhren im Mikro- und Nanometerbereich
N2 - Im Rahmen des EMPIR-Projektes NanoXSpot (Nanometre X-Ray Focal Spot Measurement) werden rückführbare Messverfahren zur Bestimmung der Brennfleckgröße und -form von Röntgenröhren mit Submikrometerauflösung (100 nm – 20 μm) entwickelt, die die Grundlage für die Erarbeitung eines Standardentwurfes bilden. Der Standardentwurf wird bei CEN TC 138 (Non-destructive testing) WG 1 (Radiographic testing) eingereicht und mit ISO und ASTM harmonisiert. Zur Untersuchung der entwickelten Methoden (Brennfleck-CT, Fit-Prozedur für Strichgruppenkörper) und des im Projekt NanoXSpot neu entworfenen Testkörpers, NxS, wurde ein Ringversuch durchgeführt. Dabei wurde sowohl der angestrebte Überlappungsbereich mit EN 12543 Teil 5 (Messung der effektiven Brennfleckgröße von Mini- und Mikrofokus-Röntgenröhren) und ASTM E 2903 (Standard Test Method for Measurement of the Effective Focal Spot Size of Mini and Micro Focus X-ray Tubes) für Brennflecke >5 μm als auch Brennflecke <5 μm untersucht. Im Mittelpunkt standen dabei Stabilität und Wiederholbarkeit der entwickelten Methoden zur Bestimmung der Brennfleckgröße. In diesem Beitrag werden die Ergebnisse des durchgeführten Ringversuches vorgestellt und diskutiert, um Schlussfolgerungen und Empfehlungen für die Vorbereitung eines erweiterten Ringversuchs mit Partnern und Stakeholdern abzuleiten.
T2 - DGZfP-Jahrestagung
CY - Kassel, Germany
DA - 23.05.2022
KW - Brennfleckmessung
KW - Computer-Tomografie
KW - EMPIR
KW - Normung
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561037
SP - 1
EP - 2
AN - OPUS4-56103
LA - deu
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -