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 -