TY - JOUR A1 - Kricheldorf, H. A1 - Weidner, Steffen T1 - Cyclic and linear poly(L-lactide)s by ring-expansion polymerization with Bu2SnO, Oct2SnO, and Bu2SnS N2 - To elucidate the usefulness of commercial Bu2SnO as catalyst for syntheses of linear and/or cyclic polylactides L-Lactide was polymerized in bulk with variation of the LA/Cat ratio, temperature and time. Based on a ring-expansion polymerization (REP) mechanism cyclic polylactides (PLAs) with weight average molecular weights in the range of 200,000–300,000 are obtained at the highest temperature (180 °C). Polymerizations at 150 °C yielded crystalline, mainly cyclic polylactides which, after annealing, showed high melting temperatures (up to 197.5 °C) and high crystallinities (>80%). Polymerization at 120 °C confirmed the trend towards more linear chains with lower temperatures but yielded extended-ring crystals showing a “saw-tooth pattern” in the mass spectra. Oct2SnO gave similar results as Bu2SnO. Bu2SnS proved a sluggish polymerization catalyst, but a good transesterification catalyst in solid PLA. KW - MALDI TOF MS KW - Biobased polymers KW - Polylactide KW - Ring-expansion polymerization PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584121 DO - https://doi.org/10.1002/pol.20230515 SN - 2642-4169 SP - 1 EP - 10 PB - Wiley CY - Hoboken, NJ AN - OPUS4-58412 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kricheldorf, H. R. A1 - Weidner, Steffen A1 - Meyer, A. T1 - About the Influence of (Non-)Solvents on the Ring Expansion Polymerization of l-Lactide and the Formation of Extended Ring Crystals N2 - Ring-expansion polymerizations (REPs) catalyzed by two cyclic tin catalysts (2-stanna-1.3-dioxa-4,5,6,7-dibenzazepine [SnBiph] and 2,2-dibutyl-2-stanna-1,3-dithiolane [DSTL]) are performed at 140 °C in bulk. Small amounts (4 vol%) of chlorobenzene or other solvents are added to facilitate transesterification reactions (ring–ring equilibration) in the solid poly(l-lactide)s. In the mass range up to m/z 13 000 crystalline PLAs displaying a so-called saw-tooth pattern in the MALDI-TOF mass spectra are obtained indicating the formation of extended-ring crystals. The characteristics of extended-ring crystallites and folded-ring crystallites are discussed. Furthermore, extremely high melting temperatures (Tm’s up to 201.2 °C) and melting enthalpies (𝚫Hm’s up to 106 J g−1)) are found confirming that 𝚫Hm max, the 𝚫Hm of a perfect crystal, is around or above 115 J g−1 in contrast to literature data. KW - Polylactide KW - MALDI-TOF MS KW - Ring-expansion polymerization KW - Biobased PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573063 DO - https://doi.org/10.1002/macp.202200385 VL - 224 IS - 5 SP - 1 EP - 8 PB - Wiley VHC-Verlag AN - OPUS4-57306 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zocca, Andrea A1 - Müller, Bernd R. A1 - Laquai, René A1 - Kupsch, Andreas A1 - Wieder, Frank A1 - Benemann, Sigrid A1 - Wilbig, Janka A1 - Günster, Jens A1 - Bruno, Giovanni T1 - Microstructural characterization of AP40 apatite-wollastonite glass-ceramic N2 - The microstructure of an apatite-wollastonite (code name AP40) glass-ceramic is analyzed in this study by combining 2D microscopy, phase analysis, X-ray absorption and synchrotron X-ray refraction computed tomography (XCT and SXRCT, respectively). It is shown that this combination provides a useful toolbox to characterize the global microstructure in a wide scale range, from sub-micrometer to millimeter. The material displays a complex microstructure comprising a glassy matrix with embedded fluorapatite and wollastonite small crystals. In this matrix, large (up to 200 μm) spike-shaped structures are distributed. Such microstructural features are oriented around a central sphere, thereby forming a structure resembling a sea urchin. A unique feature of SXRCT, in contrast to XCT, is that internal interfaces are visualized; this allows one to show the 3D distribution of these urchins with exceptionally good contrast. Furthermore, it is revealed that the spike-shaped structures are not single crystals, but rather composed of sub-micrometric crystals, which are identified as fluorapatite and diopside phases by SEM-EDX analysis. KW - Glass-ceramic KW - X-ray refraction KW - Computed tomography KW - Microstructure PY - 2023 DO - https://doi.org/10.1016/j.ceramint.2022.12.130 SN - 0272-8842 VL - 49 IS - 8 SP - 12672 EP - 12679 PB - Elsevier Science CY - Amsterdam AN - OPUS4-57452 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Becker, Roland A1 - Scholz, Philipp A1 - Jung, Christian A1 - Weidner, Steffen T1 - Thermo-Desorption Gas Chromatography-Mass Spectrometry for investigating the thermal degradation of polyurethanes N2 - Thermo-Desorption Gas Chromatography-Mass Spectrometry (TD-GC-MS) was used to investigate the thermal degradation of two different polyurethanes (PU). PU samples were heated at different heating rates and the desorbed products were collected in a cold injection system and thereafter submitted to GC-MS. Prospects and limitations of the detection and quantification of semi-volatile degradation products were investigated. A temperature dependent PU depolymerization was found at temperatures above 200 °C proved by an increasing release of 1,4-butanediol and methylene diphenyl diisocyanate (MDI) representing the main building blocks of both polymers. Their release was monitored quantitatively based on external calibration with authentic compounds. Size Exclusion Chromatography (SEC) of the residues obtained after thermodesorption confirmed the initial competitive degradation mechanism indicating an equilibrium of crosslinking and depolymerization as previously suggested. Matrix-Assisted Laser Desorption Ionization (MALDI) mass spectrometry of SEC fractions of thermally degraded PUs provided additional hints on degradation mechanism. KW - Thermo-desorption KW - Mass spectrometry KW - Polyurethanes KW - Thermal degradation PY - 2023 DO - https://doi.org/10.1039/D3AY00173C SN - 1759-9660 SP - 1 EP - 6 PB - Royal Society for Chemistry AN - OPUS4-57307 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sänger, Johanna Christiane A1 - Schwentenwein, Martin A1 - Bermejo, Raúl A1 - Günster, Jens T1 - Hybridizing Lithography-Based Ceramic Additive Manufacturing with Two-Photon-Polymerization N2 - Stereolithography processes such as lithography-based ceramic manufacturing (LCM) are technologies that can produce centimeter-sized structures in a reasonable time frame. However, for some parts specifications, they lack resolution. Two-photon-polymerization (2PP) ensures the highest geometric accuracy in additive manufacturing so far. Nevertheless, building up parts in sizes as large as a few millimeters or even centimeters is a time-consuming process, which makes the production of 2PP printed parts very costly. Regarding feedstock specification, the requirements for 2PP are different to those for LCM, and generally, feedstocks are designed to meet requirements for only one of these manufacturing technologies. In an attempt to fabricate highly precise ceramic components of a rather large size, it is necessary to develop a feedstock that suits both light-based technologies, taking advantage of LCM’s higher productivity and 2PP’s accuracy. Hybridization should bring the desired precision to the region of interest on reasonably large parts without escalating printing time and costs. In this study, specimens gained from a transparent feedstock with yttria stabilized zirconia (YSZ) particles of 5 nm at 70 wt% were presented. The resin was originally designed to suit 2PP, while being also printable with LCM. This work demonstrates how hybrid parts can be sintered into full YSZ ceramics. KW - Additive Manufacturing KW - Transparent ceramic KW - Nano-powder PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584541 DO - https://doi.org/10.3390/app13063974 SN - 2076-3417 VL - 13 IS - 6 SP - 1 EP - 9 PB - MDPI CY - Basel AN - OPUS4-58454 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Shanmugam, Sankaran A1 - Peterlechner, Martin A1 - Iskandar, Mohamad Riza A1 - Saikia, Ujjal A1 - Kulitckii, Vladislav A1 - Lipińska-Chwałek, Marta A1 - Mayer, Joachim A1 - Rösner, Harald A1 - Hickel, Tilmann A1 - Divinski, Sergiy V. A1 - Wilde, Gerhard T1 - Coherent twin-oriented Al3Sc-based precipitates in Al matrix N2 - Al3(Sc,Zr,Ti) nanoparticles with an ideal twin-type orientation relationship to Al host matrix were found in cold-rolled and subsequently annealed Al-based alloy. Atomic-scale investigations using high-resolution scanning transmission electron microscopy identified particles that form prominent coherent (111) twin-type interfaces along their longer facets and semi-coherent twin interfaces on their shorter facets. Ab-initio calculations showed that a coherent Al/Al3Sc twin-like phase boundary corresponds to a local energy minimum. A model is proposed explaining the formation of the twin orientation relationship of an Al3Sc nanoparticle with the Al host matrix. KW - Al-based alloy KW - Precipitation KW - Twin orientation relationship KW - Ab initio calculations KW - Transition electron microscopy PY - 2023 DO - https://doi.org/10.1016/j.scriptamat.2023.115351 SN - 1359-6462 VL - 229 SP - 1 EP - 6 PB - Elsevier BV AN - OPUS4-58789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Holzer, Marco A1 - Waurischk, Tina A1 - George, Janine A1 - Maaß, Robert A1 - Müller, Ralf T1 - Silicate glass fracture surface energy calculated from crystal structure and bond-energy data N2 - We present a novel method to predict the fracture surface energy, γ, of isochemically crystallizing silicate glasses using readily available crystallographic structure data of their crystalline counterpart and tabled diatomic chemical bond energies, D0. The method assumes that γ equals the fracture surface energy of the most likely cleavage plane of the crystal. Calculated values were in excellent agreement with those calculated from glass density, network connectivity and D0 data in earlier work. This finding demonstrates a remarkable equivalence between crystal cleavage planes and glass fracture surfaces. KW - Glass KW - Fracture surface energy KW - Toughness KW - Modeling KW - Mechanical properties PY - 2023 DO - https://doi.org/10.1016/j.jnoncrysol.2023.122679 SN - 0022-3093 VL - 622 SP - 1 EP - 6 PB - Elsevier B.V. AN - OPUS4-58767 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kar, S. A1 - Ikeda, Yuki A1 - Lünser, K. A1 - Woodcock, Th. G. A1 - Nielsch, K. A1 - Reith, H. A1 - Maaß, Robert A1 - Fähler, S. T1 - Growth Twins and Premartensite Microstructure in Epitaxial Ni-Mn-Ga Films N2 - Magnetic shape memory alloys have been examined intensively due to their multifunctionality and multitude of physical phenomena. For both areas, epitaxial films are promising since the absence of grain boundaries is beneficial for applications in microsystems and they also allow to understand the influence of a reduced dimension on the physical effects. Despite many efforts on epitaxial films, two particular aspects remain open. First, it is not clear how to keep epitaxial growth up to high film thickness, which is required for most microsystems. Second, it is unknown how the microstructure of premartensite, a precursor state during the martensitic transformation, manifests in films and differs from that in bulk. Here, we focus on micrometer-thick austenitic Ni-Mn-Ga films and explain two distinct microstructural features by combining high-resolution electron microscopy and X-ray diffraction methods. First, we identify pyramid-shaped defects, which originate from {1 1 1} growth twinning and cause the breakdown of epitaxial growth. We show that a sufficiently thick Cr buffer layer prevents this breakdown and allows epitaxial growth up to a thickness of at least 4 μm. Second, premartensite exhibits a hierarchical microstructure in epitaxial films. The reduced dimension of films results in variant selection and regions with distinct premartensite variants, unlike its microstructure in bulk. KW - Alloy KW - Epitaxial films KW - Hierarchical microstructure Premartensite KW - Twinning KW - Magnetic shape memory PY - 2023 DO - https://doi.org/10.1016/j.actamat.2023.118902 SN - 1359-6454 VL - 252 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-57301 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Das, A. A1 - Ott, C. A1 - Pechimuthu, Dinesh A1 - Moosavi, Robabeh A1 - Stoica, M. A1 - Derlet, P. M. A1 - Maaß, Robert T1 - Shear-band cavitation determines the shape of the stress-strain curve of metallic glasses N2 - Metallic glasses are known to have a remarkably robust yield strength, admitting Weibull moduli as high as for crystalline engineering alloys. However, their postyielding behavior is strongly varying, with large scatter in both flow stress levels and strains at failure. Using x-ray tomography, we reveal how a strain-dependent internal evolution of shear-band cavities underlies this unpredictable postyielding response.We demonstrate how macroscopic strain softening coincides with the first detection of internal shear-band cavitation. Cavity growth during plastic flow is found to follow a power law, which yields a fractal dimension and a roughness exponent in excellent agreement with self-similar surface properties obtained after fracture. These findings demonstrate how internal microcracking coexists with shear-band plasticity along the plastic part of a stress-strain curve, rationalizing the large variability of plastic flow behavior seen for metallic glasses. KW - Shear-band cavitation KW - Metallic glasses PY - 2023 DO - https://doi.org/10.1103/PhysRevMaterials.7.023602 SN - 2475-9953 VL - 7 IS - 2 SP - 1 EP - 11 PB - American Physical Society AN - OPUS4-57042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Riechers, Birte A1 - Ott, C. A1 - Das, S. M. A1 - Liebscher, C. A1 - Samwer, K. A1 - Derlet, P. M. A1 - Maaß, Robert T1 - On the elastic microstructure of bulk metallic glasses N2 - Metallic glasses (MGs) are known to be structurally heterogeneous at the nanometer (nm) scale. In addition, elastic property mapping has indicated the presence of at least an order-of-magnitude larger length scales, of which the origin continues to remain unknown. Here we demonstrate the existence of an elastic decorrelation length of the order of 100 nm in a Zr-based bulk MG using spatially resolved elastic property mapping via nanoindentation. Since compositional modulations sufficiently large to account for this elastic microstructure were not resolved by analytical scanning-transmission electron microscopy, chemical phase separation such as spinodal decomposition cannot explain their occurrence as previously suggested. Instead, we argue that the revealed long-range elastic modulations stem from structural variations affecting the local density. These emerge during solidification and are strongly influenced by the cooling constraints imposed on bulk MGs during the casting process. KW - Metallic glasses KW - Nanoindentation KW - Elastic microstructure PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573504 DO - https://doi.org/10.1016/j.matdes.2023.111929 SN - 0264-1275 VL - 229 SP - 1 EP - 8 PB - Elsevier Ltd. CY - Amsterdam, Niederlande AN - OPUS4-57350 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kruschwitz, Sabine A1 - Munsch, Sarah Mandy A1 - Telong, Melissa A1 - Schmidt, Wolfram A1 - Bintz, Thilo A1 - Fladt, Matthias A1 - Stelzner, Ludwig T1 - The NMR core analyzing TOMograph: A multi-functional tool for non-destructive testing of building materials N2 - NMR is becoming increasingly popular for the investigation of building materials as it is a non-invasive technology that does not require any sample preparation nor causes damage to the material. Depending on the specific application it can offer insights into properties like porosity and spatial saturation degree as well as pore structure. Moreover it enables the determination of moisture transport properties and the (re-)distribution of internal moisture into different reservoirs or chemical phases upon damage and curing. However, as yet most investigations were carried out using devices originally either designed for geophysical applications or the analysis of rather homogeneous small scale (< 10 mL) samples. This paper describes the capabilities of an NMR tomograph, which has been specifically optimized for the investigation of larger, heterogeneous building material samples (diameters of up to 72 mm, length of up to 700 mm) with a high flexibility due to interchangeable coils allowing for a high SNR and short echo times (50 - 80 m s). KW - Fire spalling KW - Moisture transport KW - Concrete KW - Cement hydration KW - Sensitivity KW - Supplementary cementitous materials KW - Frost salt attack PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-573755 DO - https://doi.org/10.1016/j.mrl.2023.03.004 SN - 2097-0048 VL - 3 IS - 3 SP - 207 EP - 219 PB - Elsevier B.V. AN - OPUS4-57375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cunningham, Patrick A1 - Mezhov, Alexander A1 - Schmidt, Wolfram T1 - Revealing Value from Bioderived Polymers: Effects of Locally Sourced Polysaccharides on the Rheology of Limestone Mixtures N2 - Admixtures are important constituents to enhance the performance of concrete. They allow for more efficient use of binders which can mitigate negative environmental impacts from producing cement-based materials. Commonly used rheology modifying agents like polycarboxylate ethers or cellulose ethers are synthetic or semi-synthetic, respectively. This requires additional energy consumption for their production and global supply chains particularly for many developing regions, which will be large consumers of concrete in the future. However, many locally available bio-based polysaccharides could be effectively used instead. These polymers are often overlooked by engineers and scientists due to their limited distribution and inherent complexity, yet they represent an underleveraged source of precursors for admixtures. This study investigates the action mechanisms of some bio-based rheology modifying agents, i.e., acacia gum and miscanthus gum, and provides a comparison to a conventionally modified starch. The results show that the mechanism of action of these polymers is closely related to the composition of the mixture, mixing regime, and the composition of the aqueous phase. Depending on the agent, either plasticizing or stabilizing effects on rheology can be revealed. T2 - ICBBM: International Conference on Bio-Based Building Materials CY - Vienna, Austria DA - 21.06.2023 KW - Polysaccharides KW - Superplasticizers KW - Hydration KW - Cement PY - 2023 DO - https://doi.org/10.1007/978-3-031-33465-8_60 SN - 2211-0852 VL - 45 SP - 782 EP - 792 PB - Springer Nature Switzerland AG CY - Switzerland AN - OPUS4-58726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhang, K. A1 - Mezhov, Alexander A1 - Schmidt, Wolfram T1 - Effect of Polycarboxylate Superplasticizer in Ordinary Portland Cement and Sulfate Resistant Cement N2 - Polycarboxylate superplasticizers (PCE) are the most widely used admixtures in today’s cementitious construction materials. The molecular structure has a decisive influence on the effectiveness of PCE, which also can be tailored to serve in a different cementitious system. The current study investigates the influence of the backbone charge density of PCE on the rheology, hydration kinetics, and adsorption behavior of ordinary Portland cement (OPC) and sulfate-resistant cement (SRC). The results indicate that regardless of the PCE type, OPC requires a higher amount of PCE to be adsorbed to induce changing of rheological parameters and hydration kinetics. Regardless of the cement type, the PCE with a higher charge density exhibits higher adsorption behavior, corresponding to lower viscosity measurement. Compared to OPC, SRC is more sensitive to the introduction of both PCEs and has a lower saturation dosage, indicating that SRC generally provides better workability properties regardless of the PCE. KW - Polycarboxylate superplasticizers (PCE) KW - Sulfate resistant cement (SRC) KW - Rheological KW - Adsorption KW - Cement hydration PY - 2023 DO - https://doi.org/10.1061/JMCEE7.MTENG-15033 SN - 0899-1561 VL - 35 IS - 6 SP - 1 EP - 12 PB - ASCE Libary AN - OPUS4-58244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Wolfram A1 - Kanjee, J. A1 - Motukwa, G. A1 - Olonade, K. A1 - Dodoo, A. T1 - A snapshot review of future‑oriented standards for cement, admixtures, and concrete: How Africa can spearhead the implementation of green urban construction materials N2 - The existing cement and concrete standards are not capable of making full use of the current technology capacity due to strong focus on conventional concrete and thus they are not fit for the current and future challenges of construction industry. The paper highlights shortcomings with regard to the implementation of the existing standards. It can be seen that future-oriented standards are generally required to contribute to a lower-carbon footprint of the industry. These changes are significantly more relevant in sub-Saharan Africa, due to the rapidly increasing urbanisation challenge and the enormous potentials to develop lower-carbon technologies than elsewhere in the world. KW - Future‑oriented standards KW - Green urban construction KW - Cement PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582563 DO - https://doi.org/10.1557/s43580-023-00563-9 SN - 2731-5894 VL - 4 IS - 8 SP - 557 EP - 565 PB - Springer International Publishing CY - Springer Nature Switzerland, Cham AN - OPUS4-58256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pott, U. A1 - Crasselt, Claudia A1 - Fobbe, N. A1 - Haist, M. A1 - Heinemann, M. A1 - Hellmann, S. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Lei, L. A1 - Li, R. A1 - Link, J. A1 - Lowke, D. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Nicia, D. A1 - Plank, J. A1 - Reißig, S. A1 - Schäfer, T. A1 - Schilde, C. A1 - Schmidt, Wolfram A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Strybny, B. A1 - Ukrainczyk, N. A1 - Wolf, J. A1 - Xiao, P. A1 - Stephan, D. T1 - Characterization data of reference materials used for phase II of the priority program DFG SPP 2005 “Opus Fluidum Futurum –Rheology of reactive, multiscale, multiphase construction materials” N2 - A thorough characterization of base materials is the prereq- uisite for further research. In this paper, the characterization data of the reference materials (CEM I 42.5 R, limestone pow- der, calcined clay and a mixture of these three components) used in the second funding phase of the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented under the aspects of chemical and min- eralogical composition as well as physical and chemical properties. The data were collected based on tests performed by up to eleven research groups involved in this cooperative program. KW - Portland cement KW - Limestone powder KW - Calcined clay KW - Sustainable cement KW - DFG SPP 2005 PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569913 DO - https://doi.org/10.1016/j.dib.2023.108902 VL - 47 SP - 1 EP - 19 PB - Elsevier AN - OPUS4-56991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stohl, Leonie A1 - Manninger, Tanja A1 - von Werder, Julia A1 - Dehn, F. A1 - Gorbushina, Anna A1 - Meng, Birgit T1 - Bioreceptivity of concrete - A review N2 - Materials that support natural biodiversity on their surfaces can compensate for human activities that have a negative impact on nature and thus contribute to a carbon-neutral and nature-positive world. Specifically designing bioreceptive materials which favor the growth of biofilms on their surface is an approach complementing conventional, macroscopic green façades. But what exactly characterizes a bioreceptive substrate and how do biofilm and substrate interact? How and why does a spontaneous colonization and the formation of biofilms take place? What are biofilms and how can they be established in a laboratory setting? How can this existing knowledge be transferred to the artificial stone concrete so that this material can be tuned to increase (or decrease) its bioreceptivity? This review paper aims at summarizing the existing state of knowledge on bioreceptive concrete and pointing out inconsistencies and contradictions which can only be removed by more interdisciplinary research in the field. KW - Bioreceptivity KW - Biofilm KW - Green facades KW - Developing building materials KW - Surface interactions KW - Concrete PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581685 DO - https://doi.org/10.1016/j.jobe.2023.107201 SN - 2352-7102 VL - 76 SP - 1 EP - 17 PB - Elsevier AN - OPUS4-58168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Christian A1 - Thore, Johannes A1 - Clozel, Mélanie A1 - Günster, Jens A1 - Wilbig, Janka A1 - Meyer, Andreas T1 - Additive manufacturing of metallic glass from powder in space N2 - Additive manufacturing of metals – and in particular building with laser-based powder bed fusion – is highly flexible and allows high-resolution features and feedstock savings. Meanwhile, though space stations in low Earth orbit are established, a set of visits to the Moon have been performed, and humankind can send out rovers to explore Venus and Mars, none of these milestone missions is equipped with technology to manufacture functional metallic parts or tools in space. In order to advance space exploration to long-term missions beyond low Earth orbit, it will be crucial to develop and employ technology for in-space manufacturing (ISM) and in-situ resource utilisation (ISRU). To use the advantages of laser-based powder bed fusion in these endeavours, the challenge of powder handling in microgravity must be met. Here we present a device capable of building parts using metallic powders in microgravity. This was proven on several sounding rocket flights, on which occasions Zr-based metallic glass parts produced by additive manufacturing in space were built. The findings of this work demonstrate that building parts using powder feedstock, which is more compact to transport into space than wire, is possible in microgravity environments. This thus significantly advances ISRU and ISM and paves the way for future tests in prolonged microgravity settings. KW - Metallic Glass KW - Additive Manufacturing KW - Space PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600667 DO - https://doi.org/10.1038/s41526-023-00327-7 VL - 9 SP - 1 EP - 9 PB - Springer Nature AN - OPUS4-60066 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Diener, S. A1 - Schubert, Hendrik A1 - Günster, Jens A1 - Zocca, Andrea T1 - Ink development for the additive manufacturing of strong green parts by layerwise slurry deposition (LSD-print) N2 - Obtaining dense fine ceramics by the binder jetting additive manufacturing process is challenging. A slurry-based binder jetting process, such as the layerwise slurry deposition (LSD-print) process, can enable the printing of dense ceramic parts. This work describes a procedure to develop and qualify a suitable ink to manufacture silicon carbide green parts by LSD-print. Not only the printability but also the compatibility of the ink with the powder bed and the effect of the binding agent on the properties of the green parts are considered. Both aspects are important to obtain high green strength, which is necessary for printing large or thin-walled parts. Characterization methods, such as rheological and surface tension measurements, are applied to optimize three selected inks. The interplay between ink and powder bed is tested by contact angle measurements and by comparing the biaxial strength of cast and additively manufactured specimens. Out of the three binding agents tested, a polyethyleneimine and a phenolic resin have a high potential for their use in the LSD-print of silicon carbide green bodies, whereas a polyacrylate binding agent did not show the required properties. KW - Silicon carbide KW - Binders/binding KW - Inkjet KW - Printing PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567911 DO - https://doi.org/10.1111/jace.18951 SN - 0002-7820 SP - 1 EP - 12 PB - Wiley online library AN - OPUS4-56791 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kricheldorf, H. R. A1 - Weidner, Steffen T1 - About the crystallization of cyclic and linear poly(L-lactide)s in alcohol-initiated and Sn(II)2-ethylhexanoate- catalyzed ROPs of L-lactide conducted in solution N2 - 1-Hydroxymethylnaphtalene (HMN) or 11-bromoundecanol (BUND) were used as initiators and Sn(II) 2-ethylhexanoate (SnOct2) as catalyst for ROPs of L-Lactide (LA) at 115 °C in bulk or in 4 M and 2M solutions in toluene. The LA/In ratio, the LA/Cat ratio and the time were varied. The matrix-assisted laser desorption/ionization time-of-flight (MALDI TOF) mass spectra exclusively displayed peaks of linear chains, when the ROPs were conducted in bulk. But in contrast to reports in the literature, mixtures of linear and cyclic poly(L-lactide) (PLA), were obtained, when the ROPs were performed in solution. The intensity distribution of the mass peaks of cyclic PLAs displayed a “saw-tooth pattern” after annealing in contrast to the mass peak distribution of the liner chains. This new phenomenon indicated that cyclic PLAs and linear PLAs crystallized in separate crystals from the same reaction mixture. This conclusion was confirmed by fractionated crystallization from 2 M solution, which confirmed that the cyclic PLAs nucleate and crystallize faster than the linear chains. KW - Polylactide KW - MALDI-TOF MS KW - Ring opening polymerization KW - Crystallization PY - 2023 DO - https://doi.org/10.1016/j.polymer.2023.125946 SN - 0032-3861 VL - 276 SP - 1 EP - 11 PB - Elsevier Ltd. AN - OPUS4-57308 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ginés-Palomares, J.-C. A1 - Fateri, M. A1 - Schubert, T. A1 - de Peindray d’Ambelle, L. A1 - Simon, Sebastian A1 - Gluth, Gregor A1 - Günster, Jens A1 - Zocca, Andrea T1 - Material aspects of sintering of EAC-1A lunar regolith simulant N2 - Future lunar exploration will be based on in-situ resource utilization (ISRU) techniques. The most abundant raw material on the Moon is lunar regolith, which, however, is very scarce on Earth, making the study of simulants a necessity. The objective of this study is to characterize and investigate the sintering behavior of EAC-1A lunar regolith simulant. The characterization of the simulant included the determination of the phase assemblage, characteristic temperatures determination and water content analysis. The results are discussed in the context of sintering experiments of EAC-1A simulant, which showed that the material can be sintered to a relative density close to 90%, but only within a very narrow range of temperatures (20–30 °C). Sintering experiments were performed for sieved and unsieved, as well as for dried and non-dried specimens of EAC-1A. In addition, an analysis of the densification and mechanical properties of the sintered specimens was done. The sintering experiments at different temperatures showed that the finest fraction of sieved simulant can reach a higher maximum sintering temperature, and consequently a higher densification and biaxial strength. The non-dried powder exhibited higher densification and biaxial strength after sintering compared to the dried specimen. This difference was explained with a higher green density of the non-dried powder during pressing, rather than due to an actual influence on the sintering mechanism. Nevertheless, drying the powder prior to sintering is important to avoid the overestimation of the strength of specimens to be fabricated on the Moon. KW - Lunar regolith KW - Ceramics KW - Microstructure KW - Sintering KW - Softening temperature PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-592668 DO - https://doi.org/10.1038/s41598-023-50391-y SN - 2045-2322 VL - 13 SP - 1 EP - 14 PB - Springer Nature AN - OPUS4-59266 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chabbah, T. A1 - Chatti, S. A1 - Jaffrezic-Renault, N. A1 - Weidner, Steffen A1 - Marestin, C. A1 - Mercier, R. T1 - Impedimetric sensors based on diethylphosphonate-containingpoly(arylene ether nitrile)s films for the detection of lead ions N2 - This article describes the elaboration and characterization of diethylphosphonate-containing polymers coated electrodes as sensors for the detection of heavy metalstraces, by electrochemical impedance spectroscopy. Diethylphosphonate groupswere chosen as heavy metals binding sites. Two different series of polymers bearingthese anchoring groups were synthesized. Whereas the diethylphosphonate groupsare directly incorporated in the aromatic macromolecular chain in some polymers, analiphatic spacer is removing the chelating site from the polymer backbone in others.The influence of the macromolecular structure on the sensing response was studied,especially for the detection of Pb2+,Ni2+,Cd2+and Hg2+. Polymer P6, including thehigher amount of diethylphosphonate groups removed from the polymer chain by ashort alkyl spacer gave the higher sensitivity of detection of lead ions, with a detec-tion limit of 50 pM KW - Heavy metals KW - Phosphonate esters KW - Lead ions KW - MALDI TOF MS PY - 2023 DO - https://doi.org/10.1002/pat.6065 SN - 1042-7147 SP - 1 EP - 11 PB - John Wiley & Sons, Ltd AN - OPUS4-57356 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidner, Steffen A1 - Meyer, A. A1 - Kricheldorf, H. R. T1 - Alcohol-initiated and Tin(II) 2-ethylhexanoate-catalyzed polymerization of L-lactide in bulk – About separate crystallization of cyclic and linear Poly (L-lactide)s N2 - Alcohol-initiated ROPs of L-Lactide were performed at 140 ◦C in bulk with variation of the initiator/catalyst ratio and time. Lower ratios favor the formation of cycles which upon annealing display a change of the MALDI mass peak distribution towards a new maximum with a “saw-tooth pattern” of the mass peaks representing the cycles. Such a pattern was not observed for the mass peak of the linear chains. The coexistence of these patterns indicate that linear and cyclic poly (L-lactide)s (PLA) crystallize in separate crystals, and that the crystallites of the cycles are made up by extended rings. High Tm and ΔHm values confirm that these extended-ring crystallites represent a thermodynamically optimized form of PLA. Experiments with preformed cyclic and linear PLAs support this interpretation. KW - Polylactide KW - MALDI-TOF MS KW - Crystalinity KW - Polymerization PY - 2023 DO - https://doi.org/10.1016/j.polymer.2023.126355 VL - 285 IS - 126355 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-58355 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Sokolowski‐Tinten, Klaus T1 - Probing Laser‐Driven Structure Formation at Extreme Scales in Space and Time N2 - Irradiation of solid surfaces with high intensity, ultrashort laser pulses triggers a variety of secondary processes that can lead to the formation of transient and permanent structures over a large range of length scales from mm down to the nano‐range. One of the most prominent examples are LIPSS – Laser‐Induced Periodic Surface Structures. While LIPSS have been a scientific evergreen for of almost 60 years, experimental methods that combine ultrafast temporal with the required nm spatial resolution have become available only recently with the advent of short pulse, short wavelength free electron lasers. Here, the current status and future perspectives in this field are discussed by exploiting the unique possibilities of these 4th‐generation light sources to address by time‐domain experimental techniques the fundamental LIPSS‐question, namely why and how laser irradiation can initiate the transition of a “chaotic” (rough) surface from an aperiodic into a periodic structure. KW - Laser-induced periodic surface structures (LIPSS) KW - Free electron laser KW - Pump-probe experiments KW - Time-resolved scattering KW - Capillary waves PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595048 DO - https://doi.org/10.1002/lpor.202300912 SN - 1863-8899 VL - 18 SP - 1 EP - 11 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-59504 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Keshmiri, Hamid A1 - Cikes, Domagoj A1 - Samalova, Marketa A1 - Schindler, Lukas A1 - Appel, Lisa-Marie A1 - Urbanek, Michal A1 - Yudushkin, Ivan A1 - Slade, Dea A1 - Weninger, Wolfgang J. A1 - Peaucelle, Alexis A1 - Penninger, Josef A1 - Elsayad, Kareem T1 - Brillouin light scattering anisotropy microscopy for imaging the viscoelastic anisotropy in living cells N2 - Maintaining and modulating mechanical anisotropy is essential for biological processes. However, how this is achieved at the microscopic scale in living soft matter is not always clear. Although Brillouin light scattering (BLS) spectroscopy can probe the mechanical properties of materials, spatiotemporal mapping of mechanical anisotropies in living matter with BLS microscopy has been complicated by the need for sequential measurements with tilted excitation and detection angles. Here we introduce Brillouin light scattering anisotropy microscopy (BLAM) for mapping high-frequency viscoelastic anisotropy inside living cells. BLAM employs a radial virtually imaged phased array that enables the collection of angle-resolved dispersion in a single shot, thus enabling us to probe phonon modes in living matter along different directions simultaneously. We demonstrate a precision of 10 MHz in the determination of the Brillouin frequency shift, at a spatial resolution of 2 µm. Following proof-of-principle experiments on muscle myofibres, we apply BLAM to the study of two fundamental biological processes. In plant cell walls, we observe a switch from anisotropic to isotropic wall properties that may lead to asymmetric growth. In mammalian cell nuclei, we uncover a spatiotemporally oscillating elastic anisotropy correlated to chromatin condensation. Our results highlight the role that high-frequency mechanics can play in the regulation of diverse fundamental processes in biological systems. We expect BLAM to find diverse applications in biomedical imaging and material characterization. KW - Optical and magnetic materials KW - Atomic and molecular physics and optics KW - Electronic PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595125 DO - https://doi.org/10.1038/s41566-023-01368-w SN - 1749-4885 SN - 1749-4893 VL - 18 IS - 3 SP - 276 EP - 285 PB - Nature Publ. Group CY - London AN - OPUS4-59512 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schuberth, Jens A1 - Ebert, Thomas A1 - Schlegel, Moritz-Caspar A1 - Rödig, Lisa A1 - Jepsen, Dirk A1 - Memelink, Robin A1 - Hauschke, Fynn T1 - The Front-Runner Approach - Facilitating Progressive Product Policy by Using Information from EU Product Databases N2 - The European Commission has recently announced two guiding principles for EU product policy: First, product policy shall ensure that the performance of front-runner products in terms of sustainability becomes the norm, and second, the effectiveness of the current Ecodesign legislative framework is going to be significantly improved. Within this paper, already existing front-runner approaches and recent and ongoing product policy-making processes were reviewed. Based on the results, an EU front-runner approach is outlined. The presented approach (i) refers to performance levels of the best products already available on the market, (ii) aggregates information in existing databases, and (iii) works semi-automated. Together, all three attributes have a high potential to facilitate and accelerate the specification of appropriate minimum requirements for products at the EU level. This way, EU policymakers can deliver on the core objectives of the Ecodesign legislative framework much better. The basic mechanism and its legal entrenchment of the approach are illustrated for the energy efficiency of energy-related products. In addition, the Front-Runner Approach can be applied to any product group in the scope of the upcoming Ecodesign for Sustainable Products Regulation and to a wide range of product-related minimum requirements, such as durability, reparability, or recycled content. The study’s objective is to suggest a tailor-made and dynamic approach to keep the EU product legislation up to date using innovative technology based on the investigation of current regulations and identify the gap. Experiences from three international case studies suggest that a front-runner approach to setting energy-performance standards can drive innovation and reduce energy consumption via promoting energy-efficient products; transparency about available products is one of the key factors and can be established by a database. The EU front-runner approach comprises extending the existing energy label database (or making use of the digital product passport) and introducing a legislative procedure that triggers changes in the energy efficiency requirements in the specific EU regulations if the database shows that a certain threshold value is reached. Challenges such as limited EU staff capacities and opportunities such as increased dynamic are discussed. KW - Ecodesign KW - ESPR KW - Energy labelling KW - EPREL KW - Policy making KW - Front-runner KW - Material efficiency KW - Resource efficiency KW - Energy efficiency PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595132 DO - https://doi.org/10.3390/en17020504 VL - 17 IS - 2 SP - 1 EP - 11 PB - MDPI AN - OPUS4-59513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Singh, Amit Kumar A1 - Mishra, Biswajit A1 - Sinha, Om Prakash T1 - Reduction Kinetics of Fluxed Iron Ore Pellets Made of Coarse Iron Ore Particles N2 - The present work demonstrates a sustainable approach of using relatively coarser iron ore particles for ironmaking. The motivation is to reduce the energy consumption in the milling of the iron ore by utilizing coarser iron ore particles (+0.05 mm) and to select a suitable binder for improving pellet properties. Iron ore fines in the range of 0.05–0.25 mm was selected and classified into three size ranges. Fluxed iron ore pellets were prepared using lime as a binder for the basicity of 0, 1, and 2. Reduction of these pellets with a packed bed of coal fines was performed in the temperature range of 900–1200 °C for a duration of 30–120 min. The direct reduction kinetics of the iron ore pellets were studied by employing diffusion and chemical reaction control models to the experimental data. The results show that pellets made with coarser iron ore particles have improved reduction behavior and kinetics. The reduction reaction is found to be a mixed control. The activation energy for the reduction reaction varies from 44.3 to 74.76 kJ mol−1 as iron ore particle size decreases from 0.25 to 0.05 mm and basicity increases from 0 to 2. KW - Materials Chemistry KW - Metals and Alloys KW - Process Metallurgy KW - Iron making PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598326 DO - https://doi.org/10.1002/srin.202300669 SN - 1611-3683 IS - 2300669 SP - 1 EP - 9 PB - Wiley VHC-Verlag AN - OPUS4-59832 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weller, Michael G. T1 - The mystery of homochirality on earth N2 - Homochirality is an obvious feature of life on Earth. On the other hand, extraterrestrial samples contain largely racemic compounds. The same is true for any common organic synthesis. Therefore, it has been a perplexing puzzle for decades how these racemates could have formed enantiomerically enriched fractions as a basis for the origin of homochiral life forms. Numerous hypotheses have been put forward as to how preferentially homochiral molecules could have formed and accumulated on Earth. In this article, it is shown that homochirality of the abiotic organic pool at the time of formation of the first self-replicating molecules is not necessary and not even probable. It is proposed to abandon the notion of a molecular ensemble and to focus on the level of individual molecules. Although the formation of the first self-replicating, most likely homochiral molecule, is a seemingly improbable event, on a closer look, it is almost inevitable that some homochiral molecules have formed simply on a statistical basis. In this case, the non-selective leap to homochirality would be one of the first steps in chemical evolution directly out of a racemic “ocean”. Moreover, most studies focus on the chirality of the primordial monomers with respect to an asymmetric carbon atom. However, any polymer with a minimal size that allows folding to a secondary structure would spontaneously lead to asymmetric higher structures (conformations). Most of the functions of these polymers would be influenced by this inherently asymmetric folding. Furthermore, a concept of physical compartmentalization based on rock nanopores in analogy to nanocavities of digital immunoassays is introduced to suggest that complex cell walls or membranes were also not required for the first steps of chemical evolution. To summarize, simple and universal mechanisms may have led to homochiral self-replicating systems in the context of chemical evolution. A homochiral monomer pool is deemed unnecessary and probably never existed on primordial Earth. N2 - Homochiralität ist ein offensichtliches Merkmal des Lebens auf der Erde. Andererseits enthalten extraterrestrische Proben überwiegend racemische Verbindungen. Dasselbe gilt für jede gängige organische Synthese. Daher war es jahrzehntelang ein Rätsel, wie diese Racemate enantiomeren-angereicherte Fraktionen als Grundlage für den Ursprung homochiraler Lebensformen bilden konnten. Zahlreiche Hypothesen wurden aufgestellt, wie sich bevorzugt homochirale Moleküle auf der Erde gebildet und angereichert haben könnten. In diesem Artikel wird gezeigt, dass Homochiralität des abiotischen organischen Pools zum Zeitpunkt der Bildung der ersten selbstreplizierenden Moleküle nicht notwendig und nicht einmal wahrscheinlich ist. Es wird vorgeschlagen, die Vorstellung eines molekularen Ensembles aufzugeben und sich auf die Ebene der einzelnen Moleküle zu konzentrieren. Obwohl die Bildung des ersten selbstreplizierenden, höchstwahrscheinlich homochiralen Moleküls ein scheinbar unwahrscheinliches Ereignis ist, ist es bei näherer Betrachtung fast unvermeidlich, dass sich einige homochirale Moleküle einfach auf statistischer Basis gebildet haben. In diesem Fall wäre der nichtselektive Sprung zur Homochiralität einer der ersten Schritte der chemischen Evolution direkt aus einem racemischen "Ozean". Darüber hinaus konzentrieren sich die meisten Studien auf die Chiralität der ursprünglichen Monomere in Bezug auf ein asymmetrisches Kohlenstoffatom. Jedes Polymer mit einer Mindestgröße, die eine Faltung zu einer Sekundärstruktur erlaubt, würde jedoch spontan zu asymmetrischen höheren Strukturen (Konformationen) führen. Die meisten Funktionen dieser Polymere würden durch diese inhärent asymmetrische Faltung beeinflusst. Darüber hinaus wird ein Konzept der physikalischen Kompartimentierung auf der Basis von Gesteinsnanoporen in Analogie zu den Nanokavitäten digitaler Immunoassays vorgestellt, das darauf hindeutet, dass auch für die ersten Schritte der chemischen Evolution keine komplexen Zellwände oder Membranen notwendig waren. Zusammenfassend lässt sich sagen, dass einfache und universelle Mechanismen zu homochiralen selbstreplizierenden Systemen im Rahmen der chemischen Evolution geführt haben könnten. Ein homochiraler Monomerpool wird als unnötig angesehen, welcher auf der Urerde wahrscheinlich nie existiert hat. KW - Chemical evolution KW - Enantiomeric excess ee KW - Chirality KW - Racemate KW - Folding chirality KW - Self-assembly KW - self-replication KW - Single molecule KW - Prebiotic chemistry KW - Protein folding KW - Peptide folding KW - Proteinoid KW - Conformation KW - Segregation KW - Compartmentalization KW - Digital immunoassay KW - Porous rock KW - Miller and Urey KW - Primordial soup KW - Murchison meteorite KW - Micrometeorites KW - Tholins PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598349 DO - https://doi.org/10.3390/life14030341 SN - 2075-1729 VL - 14 IS - 3 SP - 1 EP - 13 PB - MDPI CY - Basel AN - OPUS4-59834 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Slotyuk, Lyubov A1 - Part, Florian A1 - Schlegel, Moritz-Caspar A1 - Akkerman, Floris T1 - Life Cycle Assessment of the Domestic Micro Heat and Power Generation Proton Exchange Membrane Fuel Cell in Comparison with the Gas Condensing Boiler Plus Electricity from the Grid N2 - The energy demand of private households contributes globally to 36.5% of the total CO2 emissions. To analyze the emissions reduction potential, we conducted a comparative life cycle assessment of a proton exchange membrane fuel cell in a residential application and a conventional system with a stand-alone gas condensing boiler and electricity from a grid mix. The period under review was referred to as the service life of the PEMFC and is assumed to be 10 years (83,038 h of PEMFC). The applicability of this in a single-family house built between 1991 and 2000 under German climatic conditions was investigated. The functional unit is set to the thermal energy demand of 16,244 kWh/a and electricity demand of 4919 kWh/a of a single-family house. The impact assessment method “CML 2001–August 2016” was used in this investigation. The manufacturing phase of the proton exchange membrane fuel cell showed disadvantages, whereby the use phase had significant advantages in most of the environmental impact categories as compared to the conventional energy supply system. Considering the whole life cycle, the advantages from the use phase could outperform the disadvantages from the manufacturing phase in most of the impact categories, except for ADP elements and TETP. KW - Sustainability KW - Circular Economy KW - Comparative life cycle assessment KW - Proton exchange membrane fuel cell KW - Gas condensing boiler KW - Micro heat and power generation KW - Residential application KW - Single-family house energy supply system PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598134 DO - https://doi.org/10.3390/su16062348 VL - 16 IS - 6 SP - 1 EP - 16 PB - MDPI AG AN - OPUS4-59813 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Turski Silva Diniz, Analice A1 - Schartel, Bernhard T1 - The effects of property variation on the dripping behaviour of polymers during UL94 test simulated by particle finite element method N2 - The dripping behaviour of polymers is often observed experimentally through the UL94 flammability standard test. In this work, polymeric dripping under fire is investigated numerically using particle finite element method. A parametric analysis was carried out to observe the influence of a single property on overall dripping behaviour via a UL94 vertical test model. Surrogates and property ranges were defined for variation of the following parameters: glass transition temperature (Tg), melting temperature (Tm), decomposition temperature (Td), density (ρ), specific heat capacity (Cp), apparent effective heat of combustion of the volatiles, char yield (μ), thermal conductivity (k), and viscosity (η). Polyamide, poly(ether ether ketone), poly(methyl methacrylate), and polysulfone were used as benchmarks. Simulated results showed that specific heat capacity, thermal conductivity, and char yield allied with viscosity were the properties that most influenced dripping behaviour (starting time and occurrence). KW - Dripping KW - PFEM KW - UL 94 KW - Simulation KW - Fire behaviour PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597449 DO - https://doi.org/10.1515/epoly-2023-0194 SN - 1618-7229 VL - 24 IS - 1 PB - De Gruyter AN - OPUS4-59744 LA - eng 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 - Hassenstein, Christian A1 - Heckel, Thomas A1 - Tomasson, Ingimar A1 - Vöhringer, Daniel A1 - Berendt, Torsten A1 - Wassermann, Jonas A1 - Prager, Jens T1 - Automated Wall Thickness Evaluation for Turbine Blades Using Robot-Guided Ultrasonic Array Imaging N2 - Nondestructive testing has become an essential part of the maintenance of modern gas turbine blades and vanes since it provides an increase in both safety against critical failure and efficiency of operation. Targeted repairs of the blade’s airfoil require localized wall thickness information. This information, however, is hard to obtain by nondestructive testing due to the complex shapes of surfaces, cavities, and material characteristics. To address this problem, we introduce an automated nondestructive testing system that scans the part using an immersed ultrasonic array probe guided by a robot arm. For imaging, we adopt a two-step, surface-adaptive Total Focusing Method (TFM) approach. For each test position, the TFM allows us to identify the outer surface, followed by calculating an adaptive image of the interior of the part, where the inner surface’s position and shape are obtained. To handle the large volumes of data, the surface features are automatically extracted from the TFM images using specialized image processing algorithms. Subsequently, the collection of 2D extracted surface data is merged and smoothed in 3D space to form the outer and inner surfaces, facilitating wall thickness evaluation. With this approach, representative zones on two gas turbine vanes were tested, and the reconstructed wall thickness values were evaluated via comparison with reference data from an optical scan. For the test zones on two turbine vanes, average errors ranging from 0.05 mm to 0.1 mm were identified, with a standard deviation of 0.06–0.16 mm. KW - Automation KW - Imaging KW - Sensors KW - Testing methodologies KW - Ultrasonics PY - 2024 DO - https://doi.org/10.1115/1.4064998 SN - 2572-3901 VL - 7 SP - 021005-1 EP - 021005-12 PB - The American Society of Mechanical Engineers (ASME) CY - New York, USA AN - OPUS4-59851 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manoharan, Deepak A1 - Ranjan, Subham A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Takamizawa, Satoshi A1 - Ghosh, Soumyajit T1 - Elasto-plastic behaviour with reversible thermosalient expansion in acrylonitrile-based organic crystals N2 - Crystalline materials that exhibit reversible mechanical responses upon exposure to external stimuli have garnered significant attention owing to their potential applications in various fields. Herein, we report a crystal of (2Z,2′Z)-2,2′-(1,4-phenylene)bis(3-(4-bromophenyl)acrylonitrile) (DSBr), which displays simultaneous elasto-plastic behaviour and reversible thermosalient effects. While elasto-plastic behaviour is attributed to underlying packing features, reversible thermosalient expansion is attributed to uniaxial expansion mediated by heat. Exceptional length increase and contraction upon cooling is due to the restorative nature of weak interactions through a cooperative effect. The cooperative movement of molecules is reflected in the unidirectional expansion of the habit plane. Thermosalient reversible expansion–contraction in elasto-plastic crystals have not been discussed in the literature so far. Detailed analysis reported herein provides a comprehensive understanding of the underlying mechanism of flexibility and thermosalient responses. This crystal's unique blend of reversible thermal expansion with flexibility holds substantial promise for applications in flexible thermal actuators. KW - Materials Chemistry KW - General Chemistry PY - 2024 DO - https://doi.org/10.1039/D3TC04272C SN - 2050-7526 SP - 1 EP - 11 PB - Royal Society of Chemistry (RSC) AN - OPUS4-59527 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Taylor, Tristen L. A1 - Tukhmetova, Dariya A1 - Duong, Thi Phuong Thanh A1 - Böwe, Anna-Maria A1 - Meermann, Björn A1 - Gundlach-Graham, Alexander T1 - Comparative study of the vibrating capillary nebulizer (VCN) and commercially available interfaces for on-line coupling of capillary electrophoresis with ICP-MS N2 - Capillary electrophoresis (CE) is a powerful and sensitive tool for speciation analysis when combined with inductively coupled plasma mass spectrometry (ICP-MS); however, the performance of this technique can be limited by the nature of pneumatic nebulizers. This study compares two commercially available pneumatic nebulizers to a newly introduced vibrating capillary nebulizer (VCN) for on-line coupling of CE with ICP-MS. The VCN is a low-cost, non-pneumatic nebulizer that is based on the design of capillary vibrating sharp-edge spray ionization. As a piezoelectrically driven nebulization source, the VCN creates an aerosol independent of gas flows and does not produce a low-pressure region at the nebulizer orifice. To compare the systems, we performed replicate analyses of sulfate in river water with each nebulizer and the same CE and ICP-MS instruments and determined the figures of merit of each setup. With the CE-VCN-ICP-MS setup, we achieved around 2–4 times lower sensitivity compared to the commercial setups. However, the VCN-based setup provided lower noise levels and better linear correlation from the analysis of calibration standards, which resulted in indistinguishable LOD and LOQ values from the in-house-built VCN-based and commercial setups for CE-ICP-MS analysis. The VCN is found to have the highest baseline stability with a standard deviation of 3500 cts s−1, corresponding to an RSD of 2.7%. High reproducibility is found with the VCN with a peak area RSD of 4.1% between 3 replicate measurements. KW - Speciation analysis KW - Analytical chemistry KW - Surface water PY - 2024 DO - https://doi.org/10.1007/s00216-024-05162-7 SN - 1618-2650 SP - 1 EP - 9 PB - Springer CY - Berlin AN - OPUS4-59472 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sanchez Olivares, G. A1 - Rockel, Daniel A1 - Calderas, F. A1 - Schartel, Bernhard T1 - Utilizing leather fibers from industrial wastes as bio-filler to improve flame retardancy in polypropylene N2 - Combining buffing leather fibers from industrial waste streams with ammonium polyphosphate and bentonite clay is proposed as a flame-retardant additive for polypropylene. The paper addresses how they can be processed into attractive composites with the desired mechanical properties. Buffing leather fibers function as a multifunctional bio-filler and as a synergist for the flame retardant, resulting in fire retardancy successful enough to increase the oxygen index (LOI) by up to 7 vol.-% and to achieve a V0 UL 94 classification. Impressively reduced heat release rates are obtained in the cone calorimeter at 50 kW/m2 irradiation; for instance, the maximum average rate heat evolved (MARHE) drops from 765 to below 200 kW m􀀀 2. The synergistic effects are quantified and shown to be very strong for LOI and MARHE. This work opens the door to use waste buffing leather fibers as a promising multifunctional and synergistic bio-filler. KW - Polypropylene KW - Flame retardancy KW - Industrial waste KW - Leather fibers KW - Bio-filler PY - 2024 DO - https://doi.org/10.1016/j.jiec.2023.11.008 SN - 1226-086X SN - 1876-794X VL - 132 SP - 148 EP - 160 PB - Elsevier B.V. AN - OPUS4-59556 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 - Schwarz, I. A1 - Rieck, Arielle A1 - Mehmood, Asad A1 - Bublitz, R. A1 - Bongers, L. A1 - Weuster-Botz, D. A1 - Fellinger, Tim-Patrick T1 - PEM Electrolysis in a Stirred-Tank Bioreactor Enables Autotrophic Growth of Clostridium ragsdalei with CO2 and Electrons N2 - Acetogenic bacteria produce CO2-based chemicals in aqueous media by hydrogenotrophic conversion of CO2, but CO is the preferred carbon and electron source. Consequently, coupling CO2 electrolysis with bacterial fermentation within an integrated bio-electrocatalytical system (BES) is promising, if CO2 reduction catalysts are available for the generation of CO in the complex biotic electrolyte. A standard stirred-tank bioreactor was coupled to a zero-gap PEM electrolysis cell for CO2 conversion, allowing voltage control and separation of the anode in one single cell. The cathodic CO2 reduction and the competing hydrogen evolution enabled in-situ feeding of C. ragsdalei with CO and H2. Proof-of-concept was demonstrated in first batch processes with continuous CO2 gassing, as autotrophic growth and acetate formation was observed in the stirred BES in a voltage range of −2.4 to −3.0 V. The setup is suitable also for other bioelectrocatalytic reactions. Increased currents and lower overvoltages are however required. Atomically-dispersed M−N−C catalysts show promise, if degradation throughout autoclaving can be omitted. The development of selective and autoclavable catalysts resistant to contamination and electrode design for the complex electrolyte will enable efficient bioelectrocatalytic power-to-X systems based on the introduced BES. KW - Energy Conversion PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594766 DO - https://doi.org/10.1002/celc.202300344 SN - 2196-0216 SP - 1 EP - 10 PB - Wiley VHC-Verlag AN - OPUS4-59476 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Su, Bin A1 - Luo, Zhenmin A1 - Krietsch, Arne A1 - Wu, Dejian A1 - Wang, Tao A1 - Zhou, Shangyong A1 - Deng, Jun T1 - Quantitative investigation of explosion behavior and spectral radiant characteristics of free radicals for syngas/air mixtures N2 - The combustion characteristics and explosive hazard of syngas (H2/CO)/air mixtures are affected by its exact composition and equivalence ratios. In this paper, the explosion pressure and spectral radiant intensity of free radicals were quantitatively examined for syngas with different H2 proportions ([H2 in syngas] = 0, 30, 50, 70, 100 vol%) and equivalence ratios (φ = 0.8, 1.0, 1.2, 1.4, 1.6, 2.0, 2.5). The results show that the explosion process of syngas/air mixtures can be separated into the initial slow combustion stage, the violent deflagration stage and the deflagration ending stage. The peaks of explosion pressure, pressure rise rate, OH*spectral intensity and rise rate of spectral intensity first increase and then decrease with increasing the equivalence ratio, and they reduce gradually with the decrease of H2 proportion in syngas. The H2 content in syngas greatly affects the heat release and the concentration of excited state OH*, especially for the syngas/air mixtures with smaller proportion of H2. Additionally, the presence of H2 greatly increases the deflagration index and spectral radiant index of OH* for syngas/air mixtures. The average rise rates of explosion pressure and spectral intensity of free radicals are introduced and the coupling model between them is established based on the first law of thermodynamics and the principle of chain reaction. The established model is furthermore verified by the experimental results. It is indicated that there is a linear relationship between average rise rates of explosion pressure and spectral intensity (OH*). The results can be used to improve the combustion efficiency of syngas and to guide theoretically the prevention, mitigation and control of syngas explosions. KW - Syngas KW - Hydrogen KW - Explosion pressure KW - Free radicals KW - Spectral intensity PY - 2024 DO - https://doi.org/10.1016/j.ijhydene.2023.10.280 SN - 0360-3199 VL - 50 IS - Part A SP - 1359 EP - 1368 PB - Elsevier Ltd. AN - OPUS4-59482 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 - Goller, Sebastian M. A1 - Schartel, Bernhard A1 - Krüger, Simone T1 - Block it and rock it: Smoke suppressants that form a protective layer in PA 6.6 N2 - To ensure fire safety, polymers are filled with flame retardants and smoke suppressants. To meet the highest requirements, it is essential to understand the decomposition of those polymeric materials. This study reveals interactions between polymer, smoke suppressants, and flame retardants, and discusses their impact on the materials’ flame retardancy, smoke emission, smoke toxicity, and particle emission in conventional loadings to provide deeper general understanding. Low melting oxide glass, melem, spherical silica, sepiolite, melamine polyphosphate, and boehmite in an aluminum diethylphosphinate flame-retarded polyamide 6.6 were investigated. All smoke suppressants improve the protective layer and act as an adjuvant. Silica and melem performed best under forced flaming conditions. Spherical silica reduces the peak of heat release rate by 39% and the total heat evolved by 14%, whereas 10 wt% melem lowers the total smoke production by 41%. Melem alters the mode of action of aluminum diethylphosphinate from gas to more condensed phase activity. This change reduces flame inhibition and hence smoke toxicity, but further improves the protective layer due to charring reactions in the decomposition mechanism. In addition, the sizes of the smoke particles decrease because of the prolonged time in the pyrolytic zone. This study highlights that interactions between polymer, flame retardants, and smoke suppressants can significantly determine the smoking and burning behavior. KW - Smoke suppressant KW - Flame retardancy KW - Aluminum diethylphosphinate KW - Smoke KW - Polyamide 6.6 PY - 2024 DO - https://doi.org/10.1177/07349041231220250 SN - 0734-9041 VL - 42 IS - 2 SP - 117 EP - 141 PB - SAGE Publications AN - OPUS4-59533 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 - Chazeau, E. A1 - Fabre, C. A1 - Privat, M. A1 - Godard, A. A1 - Racoeur, C. A1 - Bodio, E. A1 - Busser, B. A1 - Wegner, Karl David A1 - Sancey, L. A1 - Paul, C. A1 - Goze, C. T1 - Comparison of the In Vitro and In Vivo Behavior of a Series of NIR-II-Emitting Aza-BODIPYs Containing Different Water-Solubilizing Groups and Their Trastuzumab Antibody Conjugates N2 - The development of new fluorescent organic probes effective in the NIR-II region is currently a fast-growing field and represents a challenge in the domain of medical imaging. In this study, we have designed and synthesized an innovative series of aza-boron dipyrromethenes emitting in the NIR-II region. We have investigated the effect of different water-solubilizing groups not only on the photophysical properties of the compounds but also on their in vitro and in vivo performance after bioconjugation to the antibody trastuzumab. Remarkably, we discovered that the most lipophilic compound unexpectedly displayed the most favorable in vivo properties after bioconjugation. This underlines the profound influence that the fluorophore functionalization approach can have on the efficiency of the resulting imaging agent. KW - NIR-II KW - In vivo imaging KW - Fluorescence KW - Spectroscopy KW - Antibody conjugates PY - 2024 DO - https://doi.org/10.1021/acs.jmedchem.3c02139 SN - 1520-4804 VL - 67 IS - 5 SP - 3679 EP - 3691 PB - ACS Publications CY - Washington, DC AN - OPUS4-59607 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 - Wilrich, Thomas A1 - Wilrich, Cordula T1 - Nachbarklage gegen einen Sauerstofftank N2 - Technische Regeln im Arbeitsschutz – wie TRBS für die Betriebssicherheitsverordnung und TRGS für die Gefahrstoffverordnung – sind nicht zwingendes Recht, sondern konkretisierende Empfehlungen mit Vermutungswirkung. In Gerichtsurteilen werden sie eher selten herangezogen. Wie diese – und Branchenregelungen von Verbänden – von der Rechtsprechung diskutiert werden, zeigt ein Urteil des Verwaltungsgerichts Münster. KW - Arbeitsschutz KW - Betriebssicherheitsverordnung KW - Branchenregelung KW - Gefahrstoffverordnung KW - Nachbarklage KW - Sauerstofftank KW - Sicherheitsabstand KW - TRBS KW - TRGS KW - Anlagensicherheit PY - 2024 UR - https://beprdigital.de/ce/nachbarklage-gegen-einen-sauerstofftank-1/detail.html DO - https://doi.org/10.37307/j.2365-7634.2024.01.12 SN - 2199-7330 IS - 1 SP - 45 EP - 47 PB - Erich Schmidt Verlag (ESV) CY - Berlin AN - OPUS4-59614 LA - deu 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 - 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 - JOUR A1 - Blaeß, Carsten A1 - Müller, Ralf A1 - Boccaccini, A. R. T1 - Sintering and crystallization kinetics of bioactive glass 13-93 N2 - This study investigates the sintering and crystallization behavior and kinetic of the bioactive glass (BG) 13–93 with nominal composition (in mol%): 54.6 SiO2 - 1.7 P2O3 - 22.1 CaO - 6.0 Na2O - 7.9 K2O - 7.7 MgO. Sintering and crystallization were investigated non-isothermally for various particle size fractions smaller than 315 μm as well as for bulk samples. Densification was not hindered by the presence of crystalline phases across all particle size fractions. Afterwards, wollastonite was found as the dominant crystal phase at higher temperature which resorb primary surface precipitation-like quartz crystallites. The growth direction shifts into volume when the sample surface is nearly covered. The crystal growth rate of wollastonite was calculated from the crystalline surface layer thickness measured during heating. The findings of this study are relevant for the high temperature processing of BG 13–93. KW - Bioactive glass KW - Sintering KW - Crystallization PY - 2024 DO - https://doi.org/10.1016/j.jnoncrysol.2023.122790 SN - 0022-3093 VL - 627 SP - 1 EP - 7 PB - Elsevier AN - OPUS4-59337 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 - Barzegar, M. A1 - Lugovtsova, Yevgeniya A1 - Bulling, Jannis A1 - Mishurova, Tatiana A1 - Pasadas, Dario J. A1 - Ribeiro, Artur L. A1 - Ramos, Helena G. T1 - Adhesive Porosity Analysis of Composite Adhesive Joints Using Ultrasonic Guided Waves N2 - Adhesively bonded composite joints can develop voids and porosity during fabrication, leading to stress concentration and a reduced load-carrying capacity. Hence, adhesive porosity analysis during the fabrication is crucial to ensure the required quality and reliability. Ultrasonic-guided wave (UGW)-based techniques without advanced signal processing often provide low-resolution imaging and can be ineffective for detecting small-size defects. This article proposes a damage imaging process for adhesive porosity analysis of bonded composite plates using UGWs measured by scanning laser Doppler vibrometer (LDV). To implement this approach, a piezoelectric transducer is mounted on the composite joint specimen to generate UGWs, which are measured over a densely sampled area. The signals obtained from the scan are processed using the proposed signal processing in different domains. Through the utilization of filter banks in frequency and wavenumber domains, along with the root-mean-square calculation of filtered signals, damage images of the adhesive region are obtained. It has been observed that different filters provide information related to different void sizes. Combining all the images reconstructed by filters, a final image is obtained which contains damages of various sizes. The images obtained by the proposed method are verified by radiography results and the porosity analysis is presented. The results indicate that the proposed methodology can detect the pores with the smallest detectable pore area of 2.41 mm^2, corresponding to a radius of 0.88 mm, with an overall tendency to overestimate the pore size by an average of 11%. KW - Adhesives KW - Damage imaging KW - Nondestructive testing (NDT) KW - Porosity analysis KW - Signal processing KW - Ultrasonic guided waves (UGWs) PY - 2024 DO - https://doi.org/10.1109/TUFFC.2024.3371671 VL - 71 IS - 4 SP - 485 EP - 495 PB - Institute of Electrical and Electronics Engineers (IEEE) AN - OPUS4-59970 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Isleyen, Alper A1 - Can, Suleyman Z. A1 - Cankur, Oktay A1 - Engin, Betul Ari A1 - Vogl, Jochen A1 - Koenig, Maren A1 - Horvat, Milena A1 - Jacimovic, Radojko A1 - Zuliani, Tea A1 - Fajon, Vesna A1 - Jotanovic, Aida A1 - Gaževic, Luka A1 - Milosevic, Milena A1 - Ochsenkuehn–Petropoulou, Maria A1 - Tsopelas, Fotis A1 - Lymberopoulou, Theopisti A1 - Tsakanika, Lamprini-Areti A1 - Serifi, Olga A1 - Ochsenkuehn, Klaus M. A1 - Bulska, Ewa A1 - Tomiak, Anna A1 - Kurek, Eliza A1 - Cakılbahçe, Zehra A1 - Aktas, Gokhan A1 - Altuntas, Hatice A1 - Basaran, Elif A1 - Kısacık, Barıs A1 - Gumus, Zeynep T1 - Certification of the total element mass fractions in UME EnvCRM 03 soil sample via a joint research project N2 - Soil certified reference material (CRM), UME EnvCRM 03 was produced by a collaborative approach among national metrology institutes, designated institutes and university research laboratories within the scope of the EMPIR project: Matrix Reference Materials for Environmental Analysis. This paper presents the sampling and processing methodology, homogeneity, stability, characterization campaign, the assignment of property values and their associated uncertainties in compliance with ISO 17034:2016. The material processing methodology involves blending a natural soil sample with a contaminated soil sample obtained by spiking elemental solutions for 8 elements (Cd, Co, Cu, Hg, Ni, Pb, Sb and Zn) to reach the level of warning risk monitoring values specified for metals and metalloids of soils in Europe. Comparative homogeneity and stability test data were obtained by two different institutes, ensuring the reliability and back up of the data. The certified values and associated expanded uncertainties for the total mass fractions of thirteen elements (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, V and Zn) are established. The developed CRM can be used for the development and validation of measurement procedures for the determination of the total mass fractions of elements in soil and also for quality control/assurance purposes. The developed CRM is the first example of a soil material originating from Türkiye. KW - Total element content KW - Soil KW - CRM KW - Certification KW - Environmental pollution monitoring PY - 2024 DO - https://doi.org/10.1007/s00769-024-01597-8 SN - 1432-0517 VL - 29 SP - 293 EP - 301 PB - Springer Science and Business Media LLC AN - OPUS4-59954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goswami, Juli Nanda A1 - Haque, Najirul A1 - Seikh, Asiful H. A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska A1 - Bar, Nimai A1 - Ifseisi, Ahmad A. A1 - Biswas, Surajit A1 - Dolai, Malay T1 - Carboxylative cyclization of propargyl alcohols with carbon dioxide for the synthesis of α-alkylidene cyclic carbonates in presence of Co(III) schiff base complex catalyst N2 - A cobalt(III) complex, [Co(L)3](DMF) (1) of Schiff base ligand HL, 2-((E)-(benzylimino)methyl)-4-bromophenol is prepared and single crystal X-ray structural analysis have also been performed. The structures of complex 1 showed hexa-coordinated mononuclear systems that adopt octahedral geometry. The complex has also exhibited the supramolecular networks through non-covalent interactions like H-bonding, C–Hπ stacking. Moreover, the complex 1 is very effective in the catalytic fixation of carbon dioxide in propergyl alcohols to produce α-alkylidene cyclic carbonates. The catalytic production of α-alkylidene cyclic carbonates have been carried out through carboxylative cyclization of propargyl alcohols using CO2 balloon of 1 atm pressure at 80 ◦C. Solvent free condition (green synthesis) made this catalytic protocol eco-friendly towards the environment. Utilizing various substrates of propargyl alcohols moderate to high percentage yield (62–95%) of respective α-alkylidene cyclic carbonates product have been isolated over this catalytic reaction. Besides, the theoretical calculations (DFT) was performed for the prediction of probable mechanism of the catalytic reaction KW - Catalytic fixation of carbon dioxide KW - Carboxylative cyclization of propargyl alcohols KW - Cobalt (III) Schiff base complex KW - X-ray crystal analysis PY - 2024 DO - https://doi.org/10.1016/j.molstruc.2023.136868 SN - 0022-2860 VL - 1296 IS - Part 1 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-58947 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yang, Chunliang A1 - Yan, Fan A1 - Meng, Xiangmeng A1 - Putra, Stephen Nugraha A1 - Bachmann, Marcel A1 - Rethmeier, Michael T1 - Phase-field simulation of the dendrite growth in aluminum alloy AA5754 during alternating current electromagnetic stirring laser beam welding N2 - Electromagnetic stirring is known to promote material flow, reduce porosity, uniform elements distribution, and refine grain in laser beam welding (LBW), which enhances the applicability of LBW in various industries. In this study, a phase-field model of dendrite growth in AA5754 Al alloy electromagnetic stirring laser beam welding was established. The model considered the thermal electromagnetic Lorentz force resulting from the interaction between the electric field generated by the Seebeck effect and the magnetic field, as well as the temperature gradient and solidification rate of the solidification interface obtained from the computational fluid dynamics electromagnetic stirring LBW model. The variation rules of dendrite growth with different magnetic parameters and effects are analyzed. Comprehensively, the magnetic field promotes the solidification rate, thus promoting interfacial instability and a large magnetic flux density leads to a faster interface instability. The solidification rate as well as the temperature gradient affect the growth rate, and the accelerated growth caused by the so lidification rate with a high frequency and a large magnetic flux density effectively inhibits the slow growth caused by the temperature gradient. The thermal electromagnetic Lorentz force is the main factor for the branch increment at low frequencies, while both thermal electromagnetic Lorentz force and temperature gradient in crease the number of branches at high frequencies. The calculated average branch numbers considering various factors in the stable stage under different magnetic parameters were consistent with the results of the scanning electron microscope tests. KW - Laser beam welding KW - Electromagnetic KW - Aluminum alloys KW - Phase field method KW - Dendrite growth PY - 2024 DO - https://doi.org/10.1016/j.ijheatmasstransfer.2023.124754 SN - 0017-9310 VL - 218 SP - 1 EP - 16 PB - Elsevier Ltd. AN - OPUS4-58489 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 - Peña-Diaz, Priscila A1 - Braymer, Joseph A1 - Vacek, Vojtěch A1 - Zelená, Marie A1 - Lometto, Stefano A1 - Mais, Christopher-Nils A1 - Hrdý, Ivan A1 - Treitli, Sebastian C. A1 - Hochberg, Georg K.A. A1 - Py, Béatrice A1 - Lill, Roland A1 - Hampl, Vladimír T1 - Characterization of the SUF FeS cluster synthesis machinery in the amitochondriate eukaryote Monocercomonoides exilis N2 - Monocercomonoides exilis is the first known amitochondriate eukaryote. Loss of mitochondria in M. exilis ocurred after the replacement of the essential mitochondrial iron-sulfur cluster (ISC) assembly machinery by a unique, bacteria-derived, cytosolic SUF system. It has been hypothesized that the MeSuf pathway, in cooperation with proteins of the cytosolic iron-sulfur protein assembly (CIA) system, is responsible for the biogenesis of FeS clusters in M. exilis, yet biochemical evidence is pending. Here, we address the M. exilis MeSuf system and show that SUF genes, individually or in tandem, support the loading of iron-sulfur (FeS) clusters into the reporter protein IscR in Escherichia coli. The Suf proteins MeSufB, MeSufC, and MeSufDSU interact in vivo with one another and with Suf proteins of E. coli. In vitro, the M. exilis Suf proteins form large complexes of varying composition and hence may function as a dynamic biosynthetic system in the protist. The putative FeS cluster scaffold MeSufB-MeSufC (MeSufBC) forms multiple oligomeric complexes, some of which bind FeS clusters and form selectively only in the presence of adenosine nucleotides. The multi-domain fusion protein MeSufDSU binds a PLP cofactor and can form higher-order complexes with MeSufB and MeSufC. Our work demonstrates the biochemical property of M. exilis Suf proteins to act as a functional FeS cluster assembly system and provides insights into the molecular mechanism of this unique eukaryotic SUF system. KW - Biocorrosion KW - Hydrogenases KW - Iron-sulfur clusters KW - Metalloproteins PY - 2024 DO - https://doi.org/10.1016/j.cub.2024.07.018 SP - 1 EP - 37 PB - Elsevier Inc. AN - OPUS4-60755 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Busche, Steffen A. A1 - Vigarani, Giulia A1 - Retzmann, Anika A1 - Meermann, Björn A1 - Börner, Hans G. T1 - Heavy metal on stage: Making ion-exchange resin selective by peptide tetrazine-norbornene ligation N2 - The challenge of recycling metal salt-contaminated wastewater is more relevant than ever, and cost-effective materials for specific ion-binding are required. A generic route to functionalize a macroporous polystyrene ion-exchange resin (LR-NH2) via chemoselective inverse electron-demand Diels-Alder (IEDDA) ligation is demonstrated. The resin is modified using accessible endo-/exo-5-norbornene-2-carboxylic acid (Nb-COOH) and a set of tetrazine-functionalized 5mer peptides based on sequence variations of the literature known Cu2+ binding domain HGGGW is employed for the IEDDA ligation. The resulting peptide-functionalized resins (LR-Pz-Peptides) are studied for Cu2+ binding to correlate ion-binding capacity with sequence properties by single bead analysis of metal amounts via inductively-coupled plasma mass spectrometry (ICP-MS). The complexation preferences are demonstrated and utilized for specific binding of Cu2+ versus Ni2+ from 1:1 salt mixture as a model system. Enrichment factors of up to 305 could be realized, which might open the potential for applications in metal recycling or waste water purification. KW - Heavy metals KW - Ion exchange resins KW - Analysis PY - 2024 DO - https://doi.org/10.1016/j.polymer.2023.126608 SN - 0032-3861 VL - 291 SP - 1 EP - 12 PB - Elsevier Ltd. AN - OPUS4-60756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schlick-Hasper, Eva A1 - Bethke, John T1 - Fließeigenschaften fester Gefahrgüter vor dem Hintergrund der Sicherheit beim Gefahrguttransport in Gefahrgutverpackungen - Teil 2: Vergleichende Schüttwinkeluntersuchungen N2 - In den deutschen Zulassungen für Gefahrgutverpackungen muss der minimale Schüttwinkel angegeben werden, für den die Verpackung verwendet werden darf. Dieser fungiert als Maß für die Fließeigenschaften pulverförmiger oder körniger Stoffe und ist wichtig für die Sicherheit beim Gefahrguttransport. In den Prüfstellen existiert jedoch eine Reihe von Messmethoden für diese Kenngröße. In der Vergangenheit war hierbei unklar, welche dieser Methoden für welche Prüffüllgüter prinzipiell geeignet sind. Die BAM nahm dies zum Anlass, die gebräuchlichen Messmethoden systematisch zu untersuchen. Dieser Artikel gibt einen Gesamtüberblick über die Ergebnisse und stellt die Schlussfolgerungen für die Prüfpraxis in den anerkannten Prüfstellen für Gefahrgutverpackungen dar. KW - Schüttwinkel KW - Gefahrgut KW - Fließeigenschaften PY - 2024 SN - 2191-007 VL - 14 IS - 09-10 SP - 19 EP - 24 PB - VDI Fachmedien GmbH und Co. KG CY - Düsseldorf AN - OPUS4-60986 LA - deu 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 - Parthasarathy, Thiyagaraj A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska A1 - Ghosh, Soumyajit T1 - Design of mechanically flexible photoresponsive cyanostilbene molecular crystals N2 - Photoresponsive molecular crystals have sparked interest owing to their potential application prospects. In this study, we achieved dual mechanical responses of a cyanostilbene-based crystal BN. The crystal exhibited both stress-induced mechanical flexibility and light-induced photomechanical bending. Two distinct mechanical responses are related to different underlying phenomena and were not interlinked. While elasticity is attributed to criss-cross packing arrangement in the isotropic structure, photomechanical bending is attributed to the formation of heterogeneous phase distribution due to monomer to dimer cycloaddition product formation. The crystal did not demonstrate photoswitching activity. However, it exhibited thermal reversibility, highlighting reversible dimer to monomer conversion. KW - Flexible KW - Molecular crystals PY - 2024 DO - https://doi.org/10.1039/D4CE00571F VL - 26 SP - 4634 EP - 4642 PB - Royal Society of Chemistry (RSC) AN - OPUS4-60888 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lemiasheuski, Anton A1 - Kranzmann, Axel A1 - Pfennig, Anja T1 - Herausforderungen und Möglichkeiten des manuellen metallografischen Serienschnittverfahrens anhand einer quantitativen Gefügeanalyse der Grafite eines Gusseisens T1 - Challenges and possibilities of the manual metallographic serial sectioning process using the example of a quantitative microstructural analysis of graphite in cast iron N2 - Die in dieser Studie vorgestellte 3D-Gefüge-Analyse konzentriert sich auf die Kugelgrafite eines Gusseisens des Typs EN-GJS. Es werden die Form anhand des Formfaktors und des Seitenverhältnisses sowie die durchschnittliche Teilchengröße und -verteilung untersucht. Die Form der Grafite in Gusseisenwerkstoffen ist mitentscheidend für die mechanischen Eigenschaften dieser Legierungen und ist bei der Charakterisierung des Werkstoffs unumgänglich. Mittels Metallografischen Serienschnittverfahrens wird von dem Schicht für Schicht abgetragenen und lichtmikroskopisch schichtweise dargestellten Werkstoff ein digitaler Zwilling erstellt. Von diesem dreidimensionalen Zwilling lassen sich beliebige Ebenen digital projizieren und analysieren. Eine konventionelle quantitative 3D-Analyse untersucht die Voxelmenge und -zusammensetzung eines Körpers im 3D-Raum. Die hier vorgestellte Analyse wendet stereologische 2D-Analyseverfahren auf drei Raumebenen des Werkstoffs an. Dabei sind zwei der Ebenen digitale Projektionen des Zwillings. Die zwei rekonstruierten Ebenen des Werkstoffs sind so gewählt, dass die Richtungsvektoren aller drei Ebenen einen 90°-Winkel zueinander bilden. Diese Methodik wird eingehend beschrieben sowie Herausforderungen und Möglichkeiten des hier vorgestellten Serienschnittverfahrens diskutiert. N2 - The 3D microstructure analysis presented in this study focuses on the nodular graphite of an EN-GJS grade cast iron. The shape is analyzed based on shape factor and aspect ratio as well as average particle size and distribution. The shape of graphites in cast iron materials is critical to the mechanical properties of these alloys and is essential for the characterization of the material. Metallographic serial sectioning creates a digital twin of the material, which is removed layer by layer and visualized layer by layer under an optical microscope. From this three-dimensional twin, any number of planes can be digitally projected and analyzed. Conventional quantitative 3D analysis examines the voxel count and composition of a body in 3D space. The analysis presented here applies stereological 2D analysis methods to three spatial planes of the material. Two of the planes are digital projections of the twin. The two reconstructed planes of the material are chosen so that the direction vectors of all three planes form an angle of 90° to each other. The methodology is described in detail and the challenges and opportunities of the serial section method presented here are discussed. KW - Dreidimensionale Gefügeanalyse KW - Three-dimensional microstructure analysis KW - 3D-Metallografie KW - Serienschnittverfahren KW - Gefügerekonstruktion KW - Quantitative Gefügeanalyse KW - 3D metallography KW - Serial sectioning KW - Microstructure reconstruction KW - Quantitative microstructure analysis PY - 2024 DO - https://doi.org/10.1515/pm-2024-0066 SN - 0032-678X VL - 61 IS - 9-10 SP - 746 EP - 768 PB - De Gruyter CY - Berlin/Boston AN - OPUS4-60976 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schalau, Bernd T1 - Der neue Entwurf der Richtlinie VDI 3783 Blatt 1 N2 - Im November 2019 wurde der Entwurf der VDI-Richtlinie 3783 Blatt 1 „Ausbreitung von störungsbedingten Freisetzungen“ als Gründruck veröffentlicht. Neben den Einsprüchen zur Richtlinie in Bezug auf unklare Formulierungen, wurde oft das Fehlen eines Referenzprogramms, als auch die Abkehr vom etablierten Gauß-Wolken-Modell bemängelt. Im Rahmen der darauffolgenden Überarbeitung des Richtlinienentwurfs wurde ein Gauß-Wolken-Modell entwickelt, das mit einem geringen Rechenaufwand in einem begrenzten Anwendungsbereich mit dem Lagrange’schen Partikelmodell vergleichbare Berechnungsergebnisse liefert. Darüber hinaus wurden Empfehlungen zur praktischen Umsetzung von Szenarien in den neuen Richtlinienentwurf, der voraussichtlich im Oktober 2024 als Gründruck vorliegt, aufgenommen. KW - Gasausbreitung PY - 2024 SN - 2191-007 VL - 14 IS - 9-10 SP - 25 EP - 30 AN - OPUS4-60977 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schlick-Hasper, Eva A1 - Bethke, John T1 - Fließeigenschaften fester Gefahrgüter vor dem Hintergrund der Sicherheit beim Gefahrguttransport in Gefahrgutverpackungen - Teil 1: Einführung N2 - Die Fließeigenschaften fester Gefahrgüter spielen für die Sicherheit beim Gefahrguttransport eine wichtige Rolle. Diese haben einen Einfluss sowohl auf die mechanische Sicherheit der verwendeten Verpackung als auch auf die Freisetzung fester Substanzen unter normalen Beförderungsbedingungen aufgrund ungenügender Staubdichtheit. Bei festen Gefahrgütern kann es sich entweder um pulverförmige oder um körnige Stoffe handeln. Um der sicherheitsrelevanten Bedeutung der Fließeigenschaften fester Füllgüter Rechnung zu tragen, muss in den deutschen Zulassungen für Gefahrgutverpackungen der minimale Schüttwinkel angegeben werden, für welche die Verpackung verwendet werden darf. In der Praxis der Prüfstellen existiert jedoch eine Reihe von Messmethoden für diese Kenngröße. In der Vergangenheit war hierbei unklar, welche dieser Methoden für welche Prüffüllgüter prinzipiell geeignet sind. Es ist jedoch essenziell, die Vor- und Nachteile sowie die Grenzen der einzelnen Verfahren zu kennen. Dieser Artikel gibt eine Einführung in die Thematik und in experimentelle Untersuchungen, die in der BAM durchgeführt wurden, um eine Klärung herbeizuführen. Die Ergebnisse dieser Versuche werden in einem Folgeartikel vorgestellt. KW - Schüttwinkel KW - Gefahrgut KW - Fließeigenschaften PY - 2024 VL - 14 IS - 07-08 SP - 23 EP - 29 PB - VDI Fachmedien GmbH und Co. KG CY - Düsseldorf AN - OPUS4-60985 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scholz, Philipp A1 - Vogel, Christian A1 - Schuck, G. A1 - Simon, Franz-Georg T1 - Speciation of copper and zinc compounds relevant for the hazard property (HP) 14 classification of municipal solid waste incineration bottom and fly ashes N2 - The analysis of the presence and content of substances that are toxic to aquatic life in waste is essential for classification of waste with regard to hazard property (HP) 14 ‘ecotoxic’. For the determination of HP14 classified copper (Cu) and zinc (Zn) compounds in various municipal solid waste incineration bottom ashes (IBA) and one fly ash (FA) from Germany we applied X-ray absorption near-edge structure (XANES) spectroscopy in combination with linear combination fitting. The analysis showed that approx. 50–70% of Cu in the IBA are Cu(I) compounds and elemental Cu(0), but these compounds were not equally distributed in the different IBA. In contrast, the majority (approx. 50–70%) of Zn in all IBA is elemental zinc, which originates from brass or other alloys and galvanized metals with a large content of zinc in the waste. The FA contain higher mass fraction on Zn and other toxic elements, but similar Cu and Zn species. Additional performed selective extraction at a pH of 4 with an organic acid of some IBA showed that the ecotoxic Zn fraction is mainly elemental zinc and zinc oxide. In contrast, for the ecotoxic Cu fraction within the IBA no specific compound could be identified. Furthermore, the XANES analysis showed that the HP14 properties of especially Cu in IBA is overestimated with current best-practice guidelines for sample processing for the current substance-related approach with the 0.1% cut-off rule for each substance. However, it should be considered whether it would not be better from an environmental point of view to take the ecotoxicologically leachable copper and zinc as a reference value. KW - Thermal waste treatment KW - XANES spectroscopy KW - Ecotoxicity KW - Incineration bottom ash PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609584 DO - https://doi.org/10.1016/j.wasman.2024.09.001 VL - 189 SP - 421 EP - 426 PB - Elsevier Ltd. AN - OPUS4-60958 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 - Diller, Johannes A1 - Siebert, Ludwig A1 - Winkler, Michael A1 - Siebert, Dorina A1 - Blankenhagen, Jakob A1 - Wenzler, David A1 - Radlbeck, Christina A1 - Mensinger, Martin T1 - An integrated approach for detecting and classifying pores and surface topology for fatigue assessment 316L manufactured by powder bed fusion of metals using a laser beam using μ$$ \mu $$CT and machine learning algorithms N2 - AbstractThis research aims to detect and analyze critical internal and surface defects in metal components manufactured by powder bed fusion of metals using a laser beam (PBF‐LB/M). The aim is to assess their impact on the fatigue behavior. Therefore, a combination of methods, including image processing of micro‐computed tomography (CT) scans, fatigue testing, and machine learning, was applied. A workflow was established to contribute to the nondestructive assessment of component quality and mechanical properties. Additionally, this study illustrates the application of machine learning to address a classification problem, specifically the categorization of pores into gas pores and lack of fusion pores. Although it was shown that internal defects exhibited a reduced impact on fatigue behavior compared with surface defects, it was noted that surface defects exert a higher influence on fatigue behavior. A machine learning algorithm was developed to predict the fatigue life using surface defect features as input parameters. KW - Fatigue KW - Machine learning KW - Micro-computed tomography KW - Powder bed fusion of metals using a laser beam KW - Quality assurance PY - 2024 DO - https://doi.org/10.1111/ffe.14375 SN - 8756-758X SP - 1 EP - 16 PB - John Wiley & Sons Ltd. AN - OPUS4-60593 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simon, Franz-Georg A1 - Scholz, Philipp A1 - Ling, Ruisi A1 - Koralewska, Ralf A1 - Gleis, Markus T1 - Aschen und Schlacken aus der Abfallverbrennung im Lichte der Ersatzbaustoffverordnung N2 - Aschen und Schlacken aus der thermischen Abfallbehandlung stellen mit rund 25% Massenanteil die größte Reststofffraktion dar. In Deutschland fallen pro Jahr rund 6 Millionen Tonnen an. Während sich die Verwertung der metallischen Anteile problemlos gestaltet, werden an die mineralische Fraktion Anforderungen bezüglich der möglichen Freisetzung von Schwermetallen sowie Chlorid und Sulfat gestellt. In der Ersatzbaustoffverordnung sind für Aschen und Schlacken aus der Abfallverbrennung zwei Materialklassen mit unterschiedlich hohen Anforderungen an die Umweltverträglichkeit definiert. Im Rahmen eines Forschungsprojekts wurde untersucht, ob mit Abtrennung der Feinfraktion von 0–2mm die höhere Materialklasse HMVA-1 erreicht werden kann. Im Ergebnis wurde eine Verbesserung des Auslaugverhaltens erzielt, doch nicht in dem Maß, dass eine Qualität nach HMVA-1 erreicht wird. Rostaschen halten aber die Anforderungen zur Deponierung auf einer DK I-Deponie sowie die Anforderungen zur Verwertung gemäß HMVA-2 sicher ein. KW - Rostasche KW - Auslaugtest KW - Ersatzbaustoff PY - 2024 DO - https://doi.org/10.37307/j.1863-9763.2024.07.08 SN - 1863-9763 VL - 56 IS - 7 SP - 407 EP - 411 PB - Erich Schmidt Verlag GmbH & Co. KG CY - Berlin AN - OPUS4-60601 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Özlü, C. A1 - Küttenbaum, Stefan A1 - Kainz, C. A1 - Braml, T. A1 - Taffe, A. T1 - Probabilistischer Nachweis einer Spannbetonbrücke – Teil 1 N2 - AbstractDer Erhalt der bestehenden Verkehrsinfrastruktur ist eine große Herausforderung, da die Bauwerke fortwährend altern, die Verkehrsbeanspruchung zunehmend steigt und deren umfassender Ersatz mit Blick auf begrenzte Budgets und Ressourcen nicht möglich ist. An Bestandsbauten können tatsächliche Materialkennwerte, Geometrien oder Einwirkungen objektspezifisch erfasst werden. Die Nachrechnung von Bestandsbrücken erfolgt in Deutschland gemäß Nachrechnungsrichtlinie nach Stufen 1 und 2 mit dem semiprobabilistischen Teilsicherheitskonzept. Nur im Ausnahmefall wird eine messbasierte Bewertung oder eine wissenschaftliche Betrachtung gemäß Stufen 3 und 4 durchgeführt. Die Einbeziehung zusätzlicher Informationen aus der Zustandserfassung bietet jedoch viele Vorteile für eine realitätsnahe Bewertung. In probabilistischen Berechnungsmethoden können solche Kenntnisse direkt in der Berechnung berücksichtigt werden. Ziel dieses zweiteiligen Beitrags ist die Vorstellung der Potenziale und Vorteile bei der direkten Berücksichtigung der Ergebnisse von zerstörungsfreien Prüfverfahren bei der Zustandsbewertung von Brückenbauwerken. Das Konzept wird an einer Spannbetonbrücke vorgestellt. Der erste Teil befasst sich mit den Möglichkeiten zur Überführung der Eingangswerte der üblichen semiprobabilistischen Berechnung in stochastische Modelle. Ausgehend von der semiprobabilistischen Nachrechnung nach derzeitigem Regelwerk wird die probabilistische Modellierung aller relevanten Basisvariablen für die Grenzzustände der Tragfähigkeit Biegung, Querkraft und Torsion ausgeführt. KW - Zuverlässigkeitsanalyse KW - Nachrechnung KW - Bestandsbauwerk PY - 2024 DO - https://doi.org/10.1002/best.202400018 VL - 119 IS - 7 SP - 509 EP - 523 PB - Wiley AN - OPUS4-60615 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Özlü, C. A1 - Küttenbaum, Stefan A1 - Kainz, C. A1 - Braml, T. A1 - Taffe, A. T1 - Probabilistischer Nachweis einer Spannbetonbrücke – Teil 2 N2 - AbstractIm zweiten Teil dieses Beitrags werden die Grenzzustandsfunktionen für die Nachweise im Grenzzustand der Tragfähigkeit für Biegung mit Normalkraft, Querkraft mit Querkraftbewehrung und Torsion vorgestellt. Die Eingangsgrößen der mechanischen Widerstandsmodelle werden durch zahlreiche Abbildungen illustriert. Auf Grundlage der probabilistischen Modelle aus dem ersten Teil dieses Aufsatzes und der mechanischen Modelle aus diesem zweiten Teil werden die probabilistischen Nachweise geführt. Die Ergebnisse aus der Zuverlässigkeitsanalyse werden mit den semiprobabilistischen Berechnungsergebnissen verglichen. Mittels Parameterstudien wird gezeigt, welche Eingangsgrößen im Standsicherheitsnachweis die größten Einflüsse auf die Bauwerkszuverlässigkeit haben. Die Messung dieser Parameter ist entsprechend besonders nützlich. Auf dieser Basis wird abschließend gezeigt, welche Chancen sich aus der Durchführung von zerstörungsfreien Bauwerksprüfungen für die Nachrechnung ergeben. KW - Zuverlässigkeitsanalyse KW - Nachrechnung KW - Bestandsbauwerk PY - 2024 DO - https://doi.org/10.1002/best.202400020 SN - 1437-1006 VL - 119 SP - 1 EP - 14 PB - Ernst & Sohn CY - Berlin AN - OPUS4-60616 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 - Hill, Sarah A1 - Infante, Heidi Goenaga A1 - Entwisle, John A1 - Strekopytov, Stanislav A1 - Ward-Deitrich, Christian A1 - Cowen, Simon A1 - Rienitz, Olaf A1 - Roethke, Anita A1 - Goerlitz, Volker A1 - Schulz, Ursula A1 - Pape, Carola A1 - Vogl, Jochen A1 - Koenig, Maren A1 - Jacimovic, Radojko A1 - Fisicaro, Paola A1 - Ren, Tongxiang A1 - Wang, Song A1 - Song, Panshu A1 - Li, Haifeng A1 - Linsky, Maré A1 - Sobina, Egor A1 - Lozano, Hernán Ezequiel A1 - Puelles, Mabel A1 - Yamani, Randa A1 - Haraldsson, Conny T1 - CCQM-K160: platinum group elements in automotive catalyst N2 - The platinum group elements (PGEs) play an important role in reducing emissions from automotive vehicles through their use in catalytic convertors but also for catalysis in the pharmaceutical industry. The immense economic value of platinum (Pt), palladium (Pd) and rhodium (Rh) highlights the importance of highly accurate measurements. Therefore, there is a need for National Metrology Institutes (NMIs) and Designated Institutes (DIs) to demonstrate measurement capability in this space. A pilot comparison (CCQM-P63) for precious metals in automotive catalyst took place in 2006, but with a limited number of institutes participating. Furthermore, this study was performed over 17 years ago. Therefore, there was a need to maintain existing capability and demonstrate new capability in a key comparison, in order to claim calibration and measurement capability claims (CMCs). With the core capability matrix, this study falls into the "Difficult to dissolve metals/metal oxides" which will support CMC categories 8 (Metal and metal alloys), 9 (Advanced materials) and 14 (Other materials). Eleven NMIs and DIs participated in the Key Comparison CCQM-K160 Platinum Group Elements in Automotive Catalyst. Participants were requested to evaluate the mass fractions of Pt, Pd and Rh in mg/kg in an unused autocatalyst material (cordierite ceramic base). The Key Comparison Reference Values (KCRVs) and Degrees of Equivalence (DoEs) were calculated utilising the NIST Decision Tree for the measurands. The participants utilised a number of sample preparation and analytical methods including hot plate digestion, microwave digestion and sodium fusion, followed by either atomic absorption spectroscopy (AAS), inductively coupled plasma optical emission spectroscopy (ICP-OES) or inductively coupled plasma mass spectrometry (ICP-MS) detection. Several calibration techniques were used, namely external calibration, standard addition, isotope dilution mass spectrometry (IDMS) and an exact matching procedure. Additionally, one participant employed instrumental neutron activation analysis (INAA) with k0 standardisation which is a direct solid analysis method. The majority of participants claimed traceability to NIST primary calibrants or their own CRMs. Furthermore, several matrix CRMs were included or spiked samples for quality control. All institutes were required to determine the dry mass fraction using the stipulated protocol. The NIST decision tree was implemented for the calculation of the KCRVs and DoEs. The participant results overall showed good agreement with the KCRV, despite the variety of dissolution procedures and measurement techniques for this highly complex matrix and challenging measurands. Successful participation in CCQM-K160 demonstrated measurement capabilities for the determination of mass fraction of Pt, Pd and Rh in the mg/kg range and will support broad scope CMC claims for a wide range of challenging matrices. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA). KW - Metrology in Chemistry KW - Traceability KW - Uncertainty PY - 2024 DO - https://doi.org/10.1088/0026-1394/61/1A/08011 VL - 61 IS - 1A SP - 1 EP - 39 PB - IOP Publishing AN - OPUS4-60524 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 - Alić, Jasna A1 - Schlegel, Moritz-Caspar A1 - Emmerling, Franziska A1 - Stolar, Tomislav T1 - Meeting the UN Sustainable Development Goals with Mechanochemistry N2 - Chemistry traditionally relies on reactions in solution, but this method is increasingly problematic due to the scale of chemical processes and their economic and environmental impact. Handling residual chemical waste, including solvents, incurs significant costs and environmental pressure. Conversely, novel chemical approaches are needed to address pressing societal issues such as climate change, energy scarcity, food insecurity, and waste pollution. Mechanochemistry, a sustainable chemistry discipline that uses mechanical action to induce chemical reactivity without bulk solvents, is a hot topic in academic research on sustainable and green chemistry. Given its fundamentally different working principles from solution chemistry, mechanochemistry offers more efficient chemical processes and the opportunity to design new chemical reactions. Mechanochemistry has a profound impact on many urgent issues facing our society and it is now necessary to use mechanochemistry to address them. This Minireview aims to provide a guide for using mechanochemistry to meet the United Nations (UN) Sustainable Development Goals (SDGs), thereby contributing to a prosperous society. Detailed analysis shows that mechanochemistry connects with most UN SDGs and offers more cost‐efficiency than other approaches together with a superior environmental performance. KW - Mechanochemistry KW - SDGs PY - 2024 DO - https://doi.org/10.1002/anie.202414745 SP - 1 EP - 3 PB - Wiley AN - OPUS4-61108 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kenges, Kairat A1 - Karafiludis, Stephanos A1 - Džunda, Róbert A1 - Tampubolon, Imelda Octa A1 - Satybaldiyev, Bagdat A1 - Emmerling, Franziska A1 - Baláž, Matej T1 - Calcite–aragonite transformation in an eggshell: a crucial role of organics and assessment of the impact of milling conditions on its extent using Taguchi design N2 - The occurrence of calcite–aragonite phase transformation when a mechanically activated eggshell is triggered by the presence of the organic material (eggshell membrane). KW - Mechanochemistry KW - Polymorphism PY - 2024 DO - https://doi.org/10.1039/D4CP02354D SP - 1 EP - 9 PB - Royal Society of Chemistry (RSC) AN - OPUS4-61110 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 - Tschirschwitz, Rico A1 - Hahn, Sarah-K. A1 - Krause, Ulrich T1 - BMBF-Vorhaben SEE-2L - Auswirkungen des thermischen Durchgehens von Second-Life-Lithium-Ionen-Batterien auf Modulebene N2 - Elektrische Energiespeicher können unter bestimmten Bedingungen thermisch Durchgehen. Dies ist mit der Freisetzung von großen Mengen an Wärme sowie toxischen und/oder brennbaren Gasen assoziiert. Um die potenziellen Auswirkungen des thermischen Durchgehens zu quantifizieren, wurden Versuche mit Zellen und Modulen mit einem Energieinhalt von bis zu E = 6,85 kWh durchgeführt. Es wurden verschiedene Kenngrößen, wie z.B. Temperatur, Spannung, Massenabbrand, qualitative Gaszusammensetzung sowie Fragmente, messtechnisch erfasst und ausgewertet. Die Ergebnisse können sowohl für Bemessungen im vorbeugenden baulichen Brandschutz als auch in der Prozess- und Anlagensicherheit verwendet werden. Ebenso können sie in Konzept des abwehrenden Brandschutzes integriert werden. KW - Auswirkungsbetrachtungen KW - Elektrische Energiespeicher KW - Lithium-Ionen-Batterie KW - Stationäre Energiespeicher KW - Thermisches Durchgehen PY - 2024 SN - 1868-6540 VL - 73. Jahrgang IS - 3 SP - 111 EP - 122 PB - Ebner Media Group GmbH & Co. KG CY - Ulm AN - OPUS4-61082 LA - deu 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 - JOUR A1 - Gaddam, Anuraag A1 - Galleani, Gustavo A1 - de Lima Reis, Vitor A1 - de Camargo, Andrea S. S. A1 - Eckert, Hellmut T1 - Structural characterization of gallium fluoride phosphate glasses by advanced solid‐state NMR methods and correlation with photophysical properties N2 - AbstractGallium fluoride phosphate glasses feature low refractive index, high energy radiation resistance, wide transmission range, and favorable emission characteristics of rare‐earth dopants. For the development of optimized glass compositions, a fundamental understanding of these properties in terms of glass structure is sought. We report nuclear magnetic resonance (NMR) structural studies of glasses in the system xGa(PO3)3–(40 − x)GaF3–20BaF2–20ZnF2–20SrF2 (x = 5, 10, 15, 20, and 25 mol%). 31P NMR results with 71Ga recoupling show that the network structure is dominated by P–O–Ga linkages, and no P–O–P linkages exist. 71Ga NMR results show that Ga is mainly six‐coordinated featuring a mixed fluoride/phosphate coordination. Quantitative estimates of this ligand distribution around gallium were obtained by 71Ga{31P} spin echo double resonance (REDOR) measurements. Photophysical properties suggest changes in the Eu(III) ligand distribution toward a fluoride‐dominated environment at low P/F ratio while the glass network is largely sustained by bridging oxygen atoms via P–O–Ga linkages. KW - Gallium KW - Glass KW - NMR KW - Oxyfluoride PY - 2024 DO - https://doi.org/10.1111/jace.20051 SN - 0002-7820 SP - 1 EP - 14 PB - Wiley AN - OPUS4-60785 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Merízio, Leonnam Gotardo A1 - Machado, Ian Pompermayer A1 - Vastamäki, Roosa A1 - de Camargo, Andréa Simone Stucchi A1 - Lastusaari, Mika T1 - Multifunctional persistent luminescent and photochromic hackmanite-based materials prepared by microwave-assisted solid-state synthesis N2 - Advanced optical materials inspired by natural minerals and non-toxic light elements, such as the Hackmanites (Na8Al6Si6O24(Cl,S)2), find vast possibilities of applications as they can simultaneously perform photochromism and persistent luminescence (PersL). In this work, we have explored a rapid and energy-efficient microwaveassisted (MASS) methodology for the synthesis of PersL and photochromic hackmanites. In addition, we have prepared hackmanite materials using a zeolite-free precursor to control the Na–Al–Si ratio and study its influence on the materials photoluminescent properties. The PersL hackmanites showed a white-bluish emission color, with up to 2 h of emission time. Zeolite-free photochromic materials were able to change the color from white to purple/blue efficiently with a few seconds of 254 nm excitation, but the usage of zeolite precursors enhanced the overall optical performance. Microwave synthesis times of 10–40 min were demonstrated to be optimal, as longer times boosted the formation of nepheline spurious phase, which decreases luminescence efficiency. In this way, the MASS method led to a reduction of reaction time up to 98 %, yielding hackmanite materials with similar photoluminescent or photochromic properties compared to those obtained by a 24 h conventional solid-state synthesis. This work represents a significant improvement toward coupling eco-friendly synthetic processes to eco-friendly solid-state materials for PersL illumination and PersL/photochromism optical marking. KW - Hackmanite KW - Persistent luminescence KW - Photochromism KW - Microwave-assisted synthesis PY - 2024 DO - https://doi.org/10.1016/j.optmat.2024.115826 SN - 0925-3467 VL - 155 SP - 1 EP - 13 PB - Elsevier B.V. AN - OPUS4-60787 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zweigle, Jonathan A1 - Simon, Fabian A1 - Meermann, Björn A1 - Zwiener, Christian T1 - Can Qualitative Nontarget Data Be Indicative of PFAS Contamination? First Evidence by Correlation with EOF in Environmental Samples N2 - We correlated nontarget screening (NTS) features and extractable organic fluorine (EOF) data for PFAS analysis in environmental samples. Soils, sediments, and ashes from different locations (Germany, France, and Lithuania) (n = 34) were analyzed via liquid chromatography-high-resolution mass spectrometry and high-resolution continuum source-graphite furnace molecular absorption spectrometry. NTS feature prioritization based on mass to carbon (m/C) and mass defect to carbon (MD/C) ratios was applied to discriminate potential PFAS features from common co-extracted organic matrix. Our results show a high correlation between quantitative EOF and the prioritized feature number (R2 = 0.87; rPearson = 0.93) and the total peak area of prioritized features (R2 = 0.97; rPearson = 0.98), while commonly applied MD ranges for filtering showed much weaker correlation with EOF. The observed correlations in PFAS-contaminated samples highlight that MD/C−m/C prioritization is associated with a good indication of the overall PFAS burden as evidenced by EOF. Also, semiquantitative data can be extracted as shown by EOF versus prioritized peak areas. The correlations indicate that weakly fluorinated compounds were negligible and that the EOF was mostly composed of highly fluorinated substances. Our method features the potential to automatically screen large NTS data sets for potential PFAS, determine the contribution of PFAS to EOF, and provide preliminary estimates of the overall PFAS burden. KW - PFAS KW - Non-target Screening KW - Sum parameter PY - 2024 DO - https://doi.org/10.1021/acs.estlett.4c00442 SN - 2328-8930 SP - 1 EP - 6 PB - American Chemical Society (ACS) AN - OPUS4-60754 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kolmangadi, Mohamed A. A1 - Wani, Y. M. A1 - Schönhals, Andreas A1 - Nikoubashman, A. T1 - Coarse-Grained Simulations of Columnar Ionic Liquid Crystals: Comparison with Experiments N2 - We simulate a homologous series of guanidinium-based columnar ionic liquid crystals (ILCs) using coarse-grained molecular dynamics (MD) simulations with the Martini force field. We systematically vary the length of alkyl side chains, ILC-n (n = 8, 12, 16), and compare our results with previous experimental findings. Experimentally, ILC-8 exhibits a narrow mesophase window and weak columnar order, while ILC-12 and ILC-16 display a broad mesophase window and high columnar order. The MD simulations show that ILC-8 forms a percolated structure, whereas the longer chain analogues self-assemble into columns, with columnar assembly becoming more prominent as the side chain length increases, in qualitative agreement with the experiments. Furthermore, the intercolumnar distance increases monotonically with increasing side chain length and decreases with increasing temperature. Finally, we find that the diffusion coefficient and ionic conductivity decrease substantially with increasing chain length, consistent with experimental observations. We attribute this decrease in mobility to the formation of hexagonally ordered columns, which restrict transport more than percolated networks. KW - Ionic liquid crystals PY - 2024 DO - https://doi.org/10.1021/acs.jpcb.4c03041 SN - 1520-6106 SP - 1 EP - 8 PB - ACS AN - OPUS4-60857 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 - Pakrashy, Sourav A1 - Chakraborty, Souvik A1 - Manna, Sounik A1 - Nanda Goswami, Juli A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska A1 - Mandal, Jishu A1 - Misra, Sourav A1 - Maiti Choudhury, Sujata A1 - Okla, Mohammad K. A1 - Bose, Adity A1 - Maurya, Pawan Kumar A1 - Majhi, Anjoy A1 - Dolai, Malay T1 - Inhibition of Human Colorectal Cancer by a Natural Product 7-Acetylhorminone and Interactions with BSA/HSA: Multispectral Analysis and In Silico and In Vitro Studies N2 - We have semi-synthesized a natural product 7-acetylhorminone from crude extract of Premna obtusifolia (Indian headache tree), which is active against colorectal cancer after probation through computational screening methods as it passed through the set parameters of pharmacokinetics (most important nonblood–brain barrier permeant) and drug likeliness (e.g., Lipinski’s, Ghose’s, Veber’s rule) which most other phytoconstituents failed to pass combined with docking with EGFR protein which is highly upregulated in the colorectal carcinoma cell. The structure of 7-acetylhorminone was confirmed by single crystal X-ray diffraction studies and 1H NMR, 13C NMR, and COSY studies. To validate the theoretical studies, first, in vitro experiments were carried out against human colorectal carcinoma cell lines (HCT116) which revealed the potent cytotoxic efficacy of 7-acetylhorminone and verified preliminary investigation. Second, the drugability of 7-acetylhorminone interaction with serum albumin proteins (HSA and BSA) is evaluated both theoretically and experimentally via steady-state fluorescence spectroscopic studies, circular dichroism, isothermal titration calorimetry, and molecular docking. In summary, this study reveals the applicability of 7-acetylhorminone as a potent drug candidate or as a combinatorial drug against colorectal cancer. KW - Molecular docking KW - In situ synthesis KW - ADMET PY - 2024 DO - https://doi.org/10.1021/acsabm.4c00335 VL - 7 IS - 5 SP - 3414 EP - 3430 PB - American Chemical Society (ACS) AN - OPUS4-61114 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 - Nerger, Tino A1 - Neumann, Patrick P. A1 - Weller, Michael G. T1 - Drone-Based Localization of Hazardous Chemicals by Passive Smart Dust N2 - The distribution of tiny sensors over a specific area was first proposed in the late 1990s as a concept known as smart dust. Several efforts focused primarily on computing and networking capabilities, but quickly ran into problems related to power supply, cost, data transmission, and environmental pollution. To overcome these limitations, we propose using paper-based (confetti-like) chemosensors that exploit the inherent selectivity of chemical reagents, such as colorimetric indicators. In this work, cheap and biodegradable passive sensors made from cellulose could successfully indicate the presence of hazardous chemicals, e.g., strong acids, by a significant color change. A conventional color digital camera attached to a drone could easily detect this from a safe distance. The collected data were processed to define the hazardous area. Our work presents a combination of the smart dust concept, chemosensing, paper-based sensor technology, and low-cost drones for flexible, sensitive, economical, and rapid detection of hazardous chemicals in high-risk scenarios. KW - Cellulose KW - Passive Smart Dust KW - Drohne KW - Kolorimetrische Sensoren PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614641 DO - https://doi.org/10.3390/s24196195 VL - 24 IS - 19 SP - 1 EP - 16 PB - MDPI AN - OPUS4-61464 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwarz, I. A1 - Rieck, Arielle A1 - Mehmood, Asad A1 - Bublitz, R. A1 - Bongers, L. A1 - Weuster-Botz, D. A1 - Fellinger, Tim-Patrick T1 - PEM Electrolysis in a Stirred-Tank Bioreactor Enables Autotrophic Growth of Clostridium ragsdalei with CO2 and Electrons N2 - Acetogenic bacteria produce CO2-based chemicals in aqueous media by hydrogenotrophic conversion of CO2, but CO is the preferred carbon and electron source. Consequently, coupling CO2 electrolysis with bacterial fermentation within an integrated bio-electrocatalytical system (BES) is promising, if CO2 reduction catalysts are available for the generation of CO in the complex biotic electrolyte. A standard stirred-tank bioreactor was coupled to a zero-gap PEM electrolysis cell for CO2 conversion, allowing voltage control and separation of the anode in one single cell. The cathodic CO2 reduction and the competing hydrogen evolution enabled in-situ feeding of C. ragsdalei with CO and H2. Proof-of-concept was demonstrated in first batch processes with continuous CO2 gassing, as autotrophic growth and acetate formation was observed in the stirred BES in a voltage range of 􀀀 2.4 to 􀀀 3.0 V. The setup is suitable also for other bioelectrocatalytic reactions. Increased currents and lower overvoltages are however requ KW - PEM KW - Stirred-Tank Bioreactor KW - Clostridium ragsdalei PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615239 UR - http://www.chemelectrochem.org/ DO - https://doi.org/10.1002/celc.202300344 VL - 11 IS - 6 SP - 1 EP - 9 PB - Chemistry Europe and Wiley-VCH GmbH AN - OPUS4-61523 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Breuninger, Esther S. A1 - Tolu, Julie A1 - Aemisegger, Franziska A1 - Thurnherr, Iris A1 - Bouchet, Sylvain A1 - Mestrot, Adrien A1 - Ossola, Rachele A1 - McNeill, Kristopher A1 - Tukhmetova, Dariya A1 - Vogl, Jochen A1 - Meermann, Björn A1 - Sonke, Jeroen E. A1 - Winkel, Lenny H. E. T1 - Marine and terrestrial contributions to atmospheric deposition fluxes of methylated arsenic species N2 - Arsenic, a toxic element from both anthropogenic and natural sources, reaches surface environments through atmospheric cycling and dry and wet deposition. Biomethylation volatilizes arsenic into the atmosphere and deposition cycles it back to the surface, affecting soil-plant systems. Chemical speciation of deposited arsenic is important for understanding further processing in soils and bioavailability. However, the range of atmospheric transport and source signature of arsenic species remain understudied. Here we report significant levels ofmethylated arsenic in precipitation, cloudwater and aerosols collected under free tropospheric conditions at Pic du Midi Observatory (France) indicating long-range transport, which is crucial for atmospheric budgets. Through chemical analyses andmoisture source diagnostics, we identify terrestrial and marine sources for distinct arsenic species. Estimated atmospheric deposition fluxes of methylated arsenic are similar to reported methylation rates in soils, highlighting atmospheric deposition as a significant, overlooked source of potentially bioavailable methylated arsenic species impacting plant uptake in soils. KW - Arsenic KW - Speciation KW - Fluxes KW - Marine KW - Terrestrial KW - Sulfur isotopes PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615551 DO - https://doi.org/10.1038/s41467-024-53974-z SN - 2041-1723 VL - 15 IS - 1 SP - 1 EP - 13 PB - Springer Science and Business Media LLC AN - OPUS4-61555 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yagdjian, H. A1 - Lecompagnon, Julien A1 - Hirsch, Philipp Daniel A1 - Ziegler, Mathias A1 - Gurka, M. T1 - Application of the thermal shock response spectrum (TSRS) methodology to various forms of heat sources by pulse thermography and comparison by using a rotating line scan contour search algorithm N2 - In this paper, we propose a novel contour search algorithm (CSA) for image processing. Its efficacy is evaluated through a comparative analysis with established techniques such as Canny Edge and Snakes: Active contour models, utilizing infrared thermography (IRT) images. Based on the new CSA, we investigate the influence of different pulse shapes on the IRT post-processing methodology, particularly focusing on the thermal shock response spectrum (TSRS), using two different heat sources: xenon flash lamps and a laser. Moreover, this allows for a more precise quantitative comparison of the TSRS with existing IRT post-processing techniques, including pulse phase thermography and thermal signal reconstruction, concerning the detection of defects in composite materials, particularly in carbon fiber-reinforced polymer. A quantitative comparison was performed using the Tanimoto criterion and signal-to-noise ratio. A more detailed analysis is conducted to identify inherent limitations and potential benefits of the new TSRS methodology. We further investigate and experimentally confirm our previous finding on the qualitative correlation between the one-dimensional thermal N-layer model and test data from the TSRS optimization process for defect determination. This correlation can eliminate the time-consuming optimization step, making TSRS a more attractive alternative to common IRT methods and enhancing the quantitative description of defects. KW - Thermography KW - Non-destructive testing KW - NDT KW - Defect identification KW - Laser KW - Contour search PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615056 DO - https://doi.org/10.1063/5.0232015 SN - 1089-7550 VL - 136 IS - 175101 SP - 1 EP - 20 PB - AIP Publishing AN - OPUS4-61505 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abed, Jehad A1 - Bai, Yanh A1 - Persaud, Daniel A1 - Kim, Jiheon A1 - Witt, Julia A1 - Hattrick.Simpers, Jason A1 - Sargent, Edward T1 - AMPERE: automated modular platform for expedited and reproducible electrochemical testing N2 - Rapid and reliable electrochemical screening is critical to accelerate the development of catalysts for sustainable energy generation and storage. This paper introduces an automated and modular platform for expedited and reproducible electrochemical testing (AMPERE), designed to enhance the efficiency and reliability of multivariate optimization. The platform integrates a liquid-handling robot with custommade modular array reactors, offering sample preparation and electrochemical testing in the same platform. Additionally, we use offline inductively coupled plasma optical emission spectroscopy (ICPOES) to measure metal concentrations in the electrolyte after the reaction, which serves as a proxy for assessing the electrochemical stability. We use the platform to conduct 168 experiments continuously in less than 40 hours to examine the influence of catalyst ink formulation on the performance of Ir, Ru, IrO2, and RuO2 for the oxygen evolution reaction (OER) in acid. We specifically investigate the role of solvent type and concentration, catalyst concentration, and binder content on the performance. We find that Ru/RuO2 catalysts show improvements in activity that are not directly linked to improvements in the electrochemical surface area or inversely correlated to Ru dissolution. This suggests a complex interplay between the catalytic performance of the drop-casted catalyst film and ink formulation. AMPERE simplifies catalyst preparation and testing at large scale, making it faster, more reliable, and accessible for widespread use. KW - Electrochemical screening KW - Automated platform KW - Catalysis KW - Energy generation and storage KW - Oxygen evolution reaction (OER) KW - MAPz@BAM PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614724 DO - https://doi.org/10.1039/d4dd00203b SP - 1 EP - 10 PB - Royal Society of Chemistry (RSC) AN - OPUS4-61472 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jauregui Rozo, Maria A1 - Sunder, S: A1 - Ruckdäschel, H. A1 - Schartel, Bernhard T1 - Char, gas, and action: Transfer of the flame-retardant modes of action in epoxy resins and their fiber-reinforced composites N2 - Flame retardants are often developed for epoxy resins and then transferred into their fiber-reinforced composites with uncertain results. Understanding this transfer in detail represents a critical scientific challenge. This study systematically compares epoxy resins with their glass-fiber reinforced composites, focusing on bisphenol A diglycidyl ether with the hardener dicyandiamide, the flame retardants melamine polyphosphate, ammonium polyphosphate, and silane ammonium polyphosphate, along with inorganic silicate. The research investigates changes in pyrolysis (thermogravimetry), flammability (UL 94, limiting oxygen index), and fire behavior (cone calorimeter) while also examining the flame-retardant modes of action and overall fire performance. The findings reveal that alterations in the amount of fuel, thermal properties, melt flow, and protective layer significantly impact ignition, flammability, and fire load, with a critical reduction in carbonaceous char within the composites preventing intumescence. This study quantifies the effects and provides a fundamental scientific understanding of the complex transfer process of flame retardants from resins to composites, offering essential insights that are of major importance for developing more effective flame-retardant materials. KW - Glas fibers KW - Epoxy resins KW - Fire behavior KW - Flammability KW - Composites KW - Flame retardants PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615371 DO - https://doi.org/10.1016/j.polymertesting.2024.108610 SN - 0142-9418 SN - 1873-2348 VL - 140 PB - Elsevier Ltd. AN - OPUS4-61537 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chaudhuri, Somsubhro A1 - Stamm, Michael A1 - Lapšanská, Ivana A1 - Lançon, Thibault A1 - Osterbrink, Lars A1 - Driebe, Thomas A1 - Hein, Daniel A1 - Harendt, René T1 - Infrared Thermography of Turbulence Patterns of Operational Wind Turbine Rotor Blades Supported With High‐Resolution Photography: KI‐VISIR Dataset N2 - With increasing wind energy capacity and installation of wind turbines, new inspection techniques are being explored to examine wind turbine rotor blades, especially during operation. A common result of surface damage phenomena (such as leading edge erosion) is the premature transition of laminar to turbulent flow on the surface of rotor blades. In the KI-VISIR (Künstliche Intelligenz Visuell und Infrarot Thermografie—Artificial Intelligence-Visual and Infrared Thermography) project, infrared thermography is used as an inspection tool to capture so-called thermal turbulence patterns (TTPs) that result from such surface contamination or damage. To complement the thermographic inspections, high-resolution photography is performed to visualise, in detail, the sites where these turbulence patterns initiate. A convolutional neural network (CNN) was developed and used to detect and localise turbulence patterns. A unique dataset combining the thermograms and visual images of operational wind turbine rotor blades has been provided, along with the simplified annotations for the turbulence patterns. Additional tools are available to allow users to use the data requiring only basic Python programming skills. KW - Thermography KW - Thermografie KW - Wind energy KW - Leading edge erosion KW - KI PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-615772 DO - https://doi.org/10.1002/we.2958 IS - e2958 SP - 1 EP - 9 PB - Wiley AN - OPUS4-61577 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -