TY - JOUR
A1 - Henning, L. M.
A1 - Müller, J. T.
A1 - Smales, Glen Jacob
A1 - Pauw, Brian Richard
A1 - Schmidt, J.
A1 - Bekheet, M. F.
A1 - Gurlo, A.
A1 - Simon, U.
T1 - Hierarchically porous and mechanically stable monoliths from ordered mesoporous silica and their water filtration potential
N2 - Mechanically stable structures with interconnected hierarchical porosity combine the benefits of both small
and large pores, such as high surface area, pore volume, and good mass transport capabilities. Hence, lightweight micro-/meso-/macroporous monoliths are prepared from ordered mesoporous silica COK-12 by means of spark plasma sintering (SPS, S-sintering) and compared to conventionally (C-) sintered monoliths. A multi-scale model is developed to fit the small angle X-ray scattering data and obtain information on the hexagonal lattice parameters, pore sizes from the macro to the micro range, as well as the dimensions of the silica population. For both sintering techniques, the overall mesoporosity, hexagonal pore ordering, and amorphous character are preserved. The monoliths' porosity (77–49%), mesopore size (6.2–5.2 nm), pore volume (0.50–0.22 g cm-3
), and specific surface area (451–180 m2 g-1) decrease with increasing processing temperature and pressure. While the difference in porosity is enhanced, the
structural parameters between the C-and S-sintered monoliths are largely converging at 900 C, except for the mesopore size and lattice parameter, whose dimensions are more extensively preserved in the
S-sintered monoliths, however, coming along with larger deviations from the theoretical lattice. Their higher mechanical properties (biaxial strength up to 49 MPa, 724 MPa HV 9.807 N) at comparable porosities and ability to withstand ultrasonic treatment and dead-end filtration up to 7 bar allow S-sintered monoliths to reach a high permeance (2634 L m-2 h-1 bar-1), permeability (1.25 x 10^-14 m2), and ability to reduce the chemical oxygen demand by 90% during filtration of a surfactant-stabilized oil in water emulsion, while indicating reasonable resistance towards fouling.
KW - SAXS
KW - Hierarchically porous
KW - Silica
KW - Water filtration
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555928
DO - https://doi.org/10.1039/D2NA00368F
SN - 2516-0230
SP - 1
EP - 17
PB - Royal Society of Chemistry
CY - Cambridge
AN - OPUS4-55592
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tielemann, Christopher
A1 - Reinsch, Stefan
A1 - Maaß, Robert
A1 - Deubener, J.
A1 - Müller, Ralf
T1 - Internal nucleation tendency and crystal surface energy obtained from bond energies and crystal lattice data
N2 - We present an easy-to-apply method to predict structural trends in the internal nucleation tendency of oxide glasses. The approach is based on calculated crystal fracture surface energies derived from easily accessible diatomic bond energy and crystal lattice data. The applicability of the method is demonstrated on literature nucleation data for isochemically crystallizing oxide glasses.
KW - Glass
KW - Nucleation tendency
KW - Fracture surface energy
KW - Crystal lattice
KW - Bond energy
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548814
DO - https://doi.org/10.1016/j.nocx.2022.100093
SN - 2590-1591
VL - 14
SP - 1
EP - 5
PB - Elsevier B.V.
AN - OPUS4-54881
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dombinov, V.
A1 - Herzel, Hannes
A1 - Meiller, M.
A1 - Müller, F.
A1 - Willbold, S.
A1 - Zang, J. W.
A1 - da Fonseca-Zang, W. A.
A1 - Adam, Christian
A1 - Klose, H.
A1 - Poorter, H.
A1 - Jablonowski, N. D.
A1 - Schrey, S. D.
T1 - Sugarcane bagasse ash as fertilizer for soybeans: Effects of added residues on ash composition, mineralogy, phosphorus extractability and plant availability
N2 - Sugarcane bagasse is commonly combusted to generate energy. Unfortunately, recycling strategies rarely consider the resulting ash as a potential fertilizer. To evaluate this recycling strategy for a sustainable circular economy, we characterized bagasse ash as a fertilizer and measured the effects of co-gasification and co-combustion of bagasse with either chicken manure or sewage sludge: on the phosphorus (P) mass fraction, P-extractability, and mineral P phases. Furthermore, we investigated the ashes as fertilizer for soybeans under greenhouse conditions. All methods in combination are reliable indicators helping to assess and predict P availability from ashes to soybeans. The fertilizer efficiency of pure bagasse ash increased with the ash amount supplied to the substrate. Nevertheless, it was not as effective as fertilization with triple-superphosphate and K2SO4, which we attributed to lower P availability. Co-gasification and co-combustion increased the P mass fraction in all bagasse-based ashes, but its extractability and availability to soybeans increased only when co-processed with chicken manure, because it enabled the formation of readily available Ca-alkali phosphates. Therefore, we recommend co-combusting biomass with alkali-rich residues to increase the availability of P from the ash to plants.
KW - Combustion and gasification
KW - Phosphate extractability and availability
KW - X-ray diffraction (XRD)
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567632
DO - https://doi.org/10.3389/fpls.2022.1041924
SN - 1664-462X
VL - 13
SP - 1
EP - 13
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-56763
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wolff, M.
A1 - Wonneberger, R.
A1 - Freiberg, K.E.
A1 - Hertwig, Andreas
A1 - Bonse, Jörn
A1 - Giebeler, L.
A1 - Koitzsch, A.
A1 - Kunz, C.
A1 - Weber, H.
A1 - Hufenbach, J.K.
A1 - Müller, F.A.
A1 - Gräf, S.
T1 - Formation of laser-induced periodic surface structures on Zr-based bulk metallic glasses with different chemical composition
N2 - Bulk metallic glasses (BMG) are amorphous metal alloys known for their unique physical and mechanical properties. In the present study, the formation of femtosecond (fs) laser-induced periodic surface structures (LIPSS) on the Zr-based BMGs Zr46Cu46Al8, Zr61Cu25Al12Ti2, Zr52.5Cu17.9Al10Ni14.6Ti5 (Vit105) and Zr57Cu15.4Al10Ni12.6Nb5 (Vit106) was investigated as a function of their different chemical composition. For this purpose, LIPSS were generated on the sample surfaces in an air environment by fs-laser irradiation (λ = 1025 nm, τ = 300 fs, frep = 100 kHz). The surface topography was characterized by scanning electron microscopy and atomic force microscopy. Moreover, the impact of LIPSS formation on the structure and chemical surface composition was analyzed before and after fs-laser irradiation by X-ray diffraction and X-ray photoelectron spectroscopy as well as by transmission electron microscopy in combination with energy dispersive X-ray spectroscopy. Despite the different chemical composition of the investigated BMGs, the fs-laser irradiation resulted in almost similar properties of the generated LIPSS patterns. In the case of Zr61Cu25Al12Ti2, Vit105 and Vit106, the surface analysis revealed the preservation of the amorphous state of the materials during fs-laser irradiation. The study demonstrated the presence of a native oxide layer on all pristine BMGs. In addition, fs-laser irradiation results in the formation of laser-induced oxide layers of larger thickness consisting of an amorphous ZrAlCu-oxide. The precise laser-structuring of BMG surfaces on the nanoscale provides a versatile alternative to thermoplastic forming of BMG surfaces and is of particular interest for the engineering of functional material surfaces.
KW - Bulk metallic glasses
KW - Femtosecond laser
KW - Laser-induced periodic surface structures (LIPSS)
KW - Chemical analysis
KW - Oxidation
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581799
DO - https://doi.org/10.1016/j.surfin.2023.103305
SN - 2468-0230
VL - 42
SP - 1
EP - 11
PB - Elsevier B.V.
AN - OPUS4-58179
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Müller, W.
A1 - Schweins, R.
A1 - Nöcker, B.
A1 - Kohlbrecher, J.
A1 - Smales, Glen Jacob
A1 - Huber, K.
T1 - Comparative study of the co-assembly behaviour of 3-chloro-4-hydroxy-phenylazo dyes with DTAB
N2 - The co-assembly of three one-fold negatively charged 3-chloro-4-hydroxy-phenylazo dyes (Yellow, Blue and Red) with the cationic surfactant dodecyltrimethylammoniumbromide (DTAB) was studied to probe dye–DTAB binding stoichiometry and assembly morphology. For each dye, phase separation was observed above a given dye : DTAB ratio with the ratio depending on the dye. While Yellow and DTAB showed liquid/liquid phase separation above Yellow : DTAB = 1 : 1.67, crystalline dye–DTAB complexes were observed for Blue–DTAB and Red–DTAB above Blue : DTAB = 1 : 2.56 and Red : DTAB = 1 : 2.94 respecively. In homogeneous solution, UV/vis spectroscopic investigations suggest stochiometries of Yellow : DTAB = 1 : 2, Blue : DTAB = 1 : 3 and Red : DTAB = 1 : 4. It was concluded, that Yellow exhibits the highest dye : DTAB binding stoichiometry in both, dye–surfactant complexes in the 2-phase region and in solution, whereas the lowest dye : DTAB binding stoichiometry was observed for Red–DTAB in both cases. The observed stoichiometries are inversely correlated to the impact dye addition has on the morphology of DTAB micelles. Generally, addition of dye to DTAB micelles leads to a reduction in spontaneous curvature of these micelles and to the formation of triaxial ellipsoidal or cylindrical micelles from oblate ellipsoidal DTAB micelles. At a DTAB concentration of 30 mM and a dye concentration of 5 mM, this effect was most pronounced for Red and least pronounced for Yellow, whilst Blue showed an intermediate effect.
KW - Dye
KW - DTAB
KW - SAXS
KW - Small-angle X-ray scattering
KW - X-ray scattering
KW - Data analysis
KW - Micelle
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-576978
DO - https://doi.org/10.1039/D3SM00501A
SN - 1744-683X
VL - 19
IS - 24
SP - 4588
EP - 4598
PB - Royal Society of Chemistry
AN - OPUS4-57697
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dal Molin, E. S.
A1 - Henning, L. M.
A1 - Müller, J. T.
A1 - Smales, Glen Jacob
A1 - Pauw, Brian Richard
A1 - Bekheet, M. F.
A1 - Gurlo, A.
A1 - Simon, U.
T1 - Robocasting of ordered mesoporous silica‐based monoliths: Rheological, textural, and mechanical characterization
N2 - Hierarchically porous, high‐surface‐area silica materials are excellent candidates for multiple applications like catalysis and environmental remediation. Shaping these materials with additive manufacturing (AM) techniques, like robocasting, could enable their use with the benefit of on‐demand, customized shaping and maximizing performance. Herein, ordered mesoporous silica COK‐12 slurries were robocasted into monoliths, containing different ratios of uncalcined COK‐12 and sodium bentonite (0–25 wt.%). The rheology of the mixed slurries is characterized by lower flow indexes (0.69 vs. 0.32) and higher yield stresses (96 vs. 259 Pa) compared to pure COK‐12 ones. Monoliths were printed in woodpile structures and calcined at 600°C. Micro‐CT measurements showed a linear shrinkage of 25% after calcination. Mechanical characterization showed increased uniaxial strength (0.20 ± 0.07 to 1.0 ± 0.3 MPa) with increasing binder/solids ratio from 13 to 25%. The amorphous, mesoporous structure of COK‐12 was retained. The structures exhibited open porosities of 52 ± 4% and showed higher specific mesopore volumes, and increased average mesopore size (6 vs. 8 nm) compared to COK‐12. Small‐angle x‐ray scattering analysis revealed an increased lattice parameter (10.3 vs. 11.0 nm) and reduced wall thickness (3.1 nm vs. 4.1 nm) of the COK‐12 in the monoliths. These properties indicate suitability for their application as porous supports and adsorbents.
KW - Industrial and Manufacturing Engineering
KW - Additive manufacturing
KW - OMS
KW - Porous materials
KW - Robocasting
KW - X-ray scattering
KW - MOUSE
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582503
DO - https://doi.org/10.1002/nano.202300109
VL - 4
IS - 11-12
SP - 615
EP - 631
PB - Wiley-VCH GmbH
AN - OPUS4-58250
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Deubener, J.
A1 - Behrens, H.
A1 - Müller, Ralf
T1 - An overview on the effect of dissolved water on the viscosity of soda lime silicate melts
N2 - In this review article, the impact of dissolved water on the viscous properties of soda lime silicate melts is addressed against the background of the upcoming switch from natural gas to hydrogen combustion. This change will lead to an increase in the total water content of the glasses by up to 0.4 mol%. In order to better define possible influences of water speciation, water-rich glasses were synthesised under increasing pressure up to the kbar range. It is shown that a distinction must be made between the influence of dissolved OH-groups and H2Omolecules in order to accurately reflect the dependence of isokom temperatures on water content. In addition, an increase of one order of magnitude in the tolerance to higher deformation rates was observed for the range of expected increased water contents during isothermal deformation processes, which is based on the timetemperature superposition principle, i.e. congruent flow curves were determined under isokomal conditions.
KW - Water in glass
KW - Viscosity
KW - Soda lime silicate glass
KW - Shear thinning
KW - Nydrogen melting
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-587276
DO - https://doi.org/10.1016/j.nocx.2023.100195
VL - 19
SP - 1
EP - 10
PB - Elsevier B.V.
AN - OPUS4-58727
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Reinsch, Stefan
A1 - Welter, T.
A1 - Müller, Ralf
A1 - Deubener, J.
T1 - Hydrogen Permeability of Tectosilicate Glasses for Tank Barrier Liners
N2 - The permeation of hydrogen gas was studied in meta-aluminous (tectosilicate) glass powders of Li2O×Al2O3×SiO2 (LAS), Na2O×Al2O3×SiO2 (NAS) and MgO×Al2O3×SiO2 (MAS) systems by pressure loading and vacuum extraction in the temperatures range 210–310 °C. With this method, both the solubility S and the diffusivity D were determined, while the permeability was given by the product SD. For all glasses, S was found to decrease with temperature, while D increased. Since the activation energy of diffusion of H2 molecules exceeded that of dissolution, permeation increased slightly with temperature. When extrapolated to standard conditions (25 °C), the permeability of tectosilicate glasses was found to be only 10-22–10-24 mol H2 (m s Pa)-1, which is 8–10 magnitudes lower than most polymers. Thin glass liners of these compositions are expected to be the most effective barrier for tanks of pressurised hydrogen.
KW - Hydrogen permeation
KW - Aluminosilicate glasses
KW - Hydrogen storage tank
KW - Glass liner
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-587284
DO - https://doi.org/10.52825/glass-europe.v1i.425
VL - 1
SP - 1
EP - 11
AN - OPUS4-58728
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Brüngel, R.
A1 - Rückert, J.
A1 - Müller, P.
A1 - Babick, F.
A1 - Friedrich, C. M.
A1 - Ghanem, A.
A1 - Hodoroaba, Vasile-Dan
A1 - Mech, A.
A1 - Weigel, S.
A1 - Wohlleben, W.
A1 - Rauscher, H.
T1 - NanoDefiner Framework and e-Tool Revisited According to the European Commission’s Nanomaterial Definition 2022/C 229/01
N2 - The new recommended definition of a nanomaterial, 2022/C 229/01, adopted by the European Commission in 2022, will have a considerable impact on European Union legislation addressing chemicals, and therefore tools to implement this new definition are urgently needed. The updated NanoDefiner framework and its e-tool implementation presented here are such instruments, which help stakeholders to find out in a straightforward way whether a material is a nanomaterial or not. They are two major outcomes of the NanoDefine project, which is explicitly referred to in the new definition. This work revisits the framework and e-tool, and elaborates necessary adjustments to make these outcomes applicable for the updated recommendation. A broad set of case studies on representative materials confirms the validity of these adjustments. To further foster the sustainability and applicability of the framework and e-tool, measures for the FAIRification of expert knowledge within the e-tool’s knowledge base are elaborated as well. The updated framework and e-tool are now ready to be used in line with the updated recommendation. The presented approach may serve as an example for reviewing existing guidance and tools developed for the previous definition 2011/696/EU, particularly those adopting NanoDefine project outcomes.
KW - Nanomaterial definition
KW - Nanomaterial categorisation
KW - Nanomaterial regulation
KW - Nanomaterial legislation
KW - Decision support
KW - FAIRification
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571618
DO - https://doi.org/10.3390/nano13060990
SN - 2079-4991
VL - 13
IS - 6 - Special Issue "Identification and Quantification of Nanomaterials"
SP - 1
EP - 16
PB - MDPI
CY - Basel, CH
AN - OPUS4-57161
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gogula, Shravya
A1 - Bornhöft, H.
A1 - Wondraczek, L.
A1 - Sierka, M.
A1 - Diegeler, A.
A1 - Müller, Ralf
A1 - Deubener, J.
T1 - Optical Real-Time Castability Evaluation for High-Throughput Glass Melting
N2 - A novel optical real-time method for evaluating the castability of glass forming melts for laboratory furnaces is presented. The method is based on the analysis of top view images of the melt surface inside the crucible during melting after being subjected to a small mechanical impulse. In this way, the melt surface is excited to oscillate. The difference in contrast between two images taken in quick succession scales with the viscosity, with a larger difference occurring at lower viscosities. The method is designed as an instrument for the in-line evaluation of the castability for a high-throughput glass melting system as part of the joint project “GlasDigital” in the framework of the German Platform Material Digital initiative but is applicable to other laboratory furnaces as well.
KW - Optical Real-Time Castability Check
KW - Image Analysis
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-618659
DO - https://doi.org/10.52825/glass-europe.v2i.1359
VL - 2
SP - 83
EP - 93
AN - OPUS4-61865
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bauer, L.J.
A1 - Wieder, Frank
A1 - Truong, V.
A1 - Förste, F.
A1 - Wagener, Y.
A1 - Jonas, A.
A1 - Praetz, S:
A1 - Schlesiger, C.
A1 - Kupsch, Andreas
A1 - Müller, Bernd R.
A1 - Kanngießer, B.
A1 - Zaslansky, P.
A1 - Mantouvalou, I.
T1 - Absorption Correction for 3D Elemental Distributions of Dental Composite Materials Using Laboratory Confocal Micro-X-ray Fluorescence Spectroscopy
N2 - Confocal micro-X-ray fluorescence (micro-XRF) spectroscopy facilitates three-dimensional (3D) elemental imaging of heterogeneous samples in the micrometer range. Laboratory setups using X-ray tube excitation render the method accessible for diverse research fields but interpretation of results and quantification remain challenging. The attenuation of X-rays in composites depends on the photon energy as well as on the composition and density of the material. For confocal micro-XRF, attenuation severely impacts elemental distribution information, as the signal from deeper layers is distorted by superficial layers. Absorption correction and quantification of fluorescence measurements in heterogeneous composite samples have so far not been reported. Here, an absorption correction approach for confocal micro-XRF combining density information from microcomputed tomography (micro-CT) data with laboratory X-ray absorption spectroscopy (XAS) and synchrotron transmission measurements is presented. The energy dependency of the probing volume is considered during the correction. The methodology is demonstrated on a model composite sample consisting of a bovine tooth with a clinically used restoration material.
KW - Micro X-ray fluorescence spectroscopy
KW - Dental composite materials
KW - Computed tomography
KW - Absorption correction
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601630
DO - https://doi.org/10.1021/acs.analchem.4c00116
SN - 0003-2700
SN - 1520-6882
VL - 96
IS - 21
SP - 8441
EP - 8449
PB - American Chemical Society Publications
CY - Washington, DC
AN - OPUS4-60163
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Reveron, H.
A1 - Serrano-Munoz, Itziar
A1 - Kupsch, Andreas
A1 - Müller, Bernd R.
A1 - Chevalier, J.
A1 - Bruno, Giovanni
T1 - Transformation-induced plasticity in zirconia during tensile loading: A combined microscopy and synchrotron X-ray refraction study
N2 - The stress-induced tetragonal to monoclinic (t-m) zirconia phase transformation can provide a certain degree of plasticity to Ceria-stabilized (Ce-TZP) zirconia-based composites. Characterizing and monitoring this phase transition on a millimeter-size range, within the bulk and in-situ remains a challenge. In this work, the mechanical behavior of Ce-TZP based composite was studied in tension, combining microscopy and synchrotron Xray refraction techniques. In contrast with microscopy methods, which only provide surface information, X-ray refraction radiography (SXRR) allowed the visualization of all the transformation bands, over the entire length and thickness of tested specimens, opening up new avenues for in-situ stress-induced t-m transformation studies.
KW - Zirconia
KW - Ceria
KW - Composite
KW - Phase transformation
KW - Plasticity
KW - Synchrotron X-ray refraction
PY - 2024
DO - https://doi.org/10.1016/j.matlet.2024.136445
SN - 0167-577X
SN - 1873-4979
VL - 366
SP - 1
EP - 4
PB - Elsevier Ltd.
CY - Amsterdam
AN - OPUS4-59977
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Waurischk, Tina
A1 - Deubener, J.
A1 - Müller, Ralf
T1 - Internal friction and energy dissipation during fracture in silicate glasses
N2 - To obtain a deeper insight into the nature of energy dissipation during fracture, the internal friction of 13 borosilicate, aluminosilicate, soda-lime, and lead-containing glasses, for which inert crack growth data are known, was measured using dynamic mechanical thermal analysis. For asymmetrically bent glass beams, the loss tangent, tan δ, was determined between 0.2 and 50 Hz at temperatures between 273 K and the glass transition temperature, Tg. It was found that the area under the tan δ vs T·Tg−1 curve correlates with the crack growth exponent, n, in the empirical v = v0·KIn relation between crack growth velocity, v, and stress intensity, KI, which indicates that n correlates with the degree of energy dissipation of sub-Tg relaxation phenomena.
KW - Glass
KW - Internal friction
KW - Crack growth
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-631582
DO - https://doi.org/10.1063/5.0255432
SN - 0021-9606
VL - 162
IS - 19
SP - 1
EP - 9
PB - AIP Publishing
AN - OPUS4-63158
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pan, Z.
A1 - Waurischk, Tina
A1 - Duval, A.
A1 - Müller, Ralf
A1 - Deubener, J.
A1 - Krishnan, N. M. A.
A1 - Wondraczek, K.
A1 - Wondraczek, L.
T1 - Precise Real‐Time Measurement of Liquid Viscosity Using Digital Video Data
N2 - Quantitative knowledge of liquid viscosity is of fundamental importance in many areas of materials synthesis and processing. However, the determination of viscosity often relies on specialized experimental equipment, offline experimentation, or invasive procedures, in particular when required in extreme conditions such as at high temperature, high pressure, and in confined or corrosive environments. Here, this study proposes and validates a fast and simple method that mimics the intuitive perception of liquid flow within a quantitative framework. For this, this study employs digital video observation to derive quantitative values of the shear viscosity of liquids, with high precision and rapid acquisition rates. The technique involves capturing liquid dynamics after minor mechanical stimulation. Processed imaging data are indexed by similarity and referenced to a digital database generated with a finite element model, from which values of viscosity are obtained in line. The approach is tested on water at room temperature and on a high‐temperature glass melt. Covering a viscosity range of four orders of magnitude, both yield convincing agreement with tabulated reference data at low computational cost.
KW - Image analyses
KW - Liquids
KW - Materials discovery
KW - Similarity analyses
KW - Viscosities
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634606
DO - https://doi.org/10.1002/aisy.202500297
SN - 2640-4567
SP - 1
EP - 12
PB - Wiley
AN - OPUS4-63460
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hartmann, Yannic
A1 - El Abbassi, Abdelouahad
A1 - Mayer, Bernhard
A1 - Resch-Genger, Ute
A1 - Müller, Thomas J. J.
T1 - Ester‐Aroyl‐S,N‐Ketene Acetals with Solid‐State Luminescence: AIEgens from Sequential Three‐Component Desymmetrization
N2 - AbstractDi(hetero)aroyl dichlorides are desymmetrized upon sequential reaction with alcohols and 2‐methyl N‐benzyl thiazolium salts within the course of a one‐pot three‐component reaction yielding ester‐substituted aroyl‐S,N‐ketene acetals under mild conditions in good yields. A prerequisite for the concise one‐pot process is the different nucleophilicity of the alcohols and in situ generated S,N‐ketene acetals. The resulting compounds are merocyanines with dominant charge‐transfer absorption bands which are fluorescent in the solid state, but not in solution. In water/ethanol solvent mixtures of increasing water content, the water‐insoluble dyes display typical aggregation‐induced emission (AIE) characteristics. The water fraction inducing AIE as well as the emission color, and fluorescence quantum yield (Φf) of the aggregated dyes can be controlled by the alcohol part of the ester moiety. Encapsulation into polystyrene nanoparticles can lead to a considerable increase of the fluorescence quantum yield Φf to 30% as shown for a representatively chosen dye revealing the highest Φf of 11% within the dye series in the water/ethanol mixtures and enabling the usage of these dyes as fluorescent reporters in aqueous environments.
KW - Dye
KW - Fluorescence
KW - Aggregation
KW - Mechanism
KW - Signal enhancement
KW - Nano
KW - Particle
KW - Characterization
KW - Quantum yield
KW - Photophysics
KW - Probe
KW - Sensor
KW - Lifetime
KW - Polarity
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-642400
DO - https://doi.org/10.1002/chem.202502071
SN - 0947-6539
SP - 1
EP - 10
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-64240
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Waurischk, Tina
A1 - Deubener, J.
A1 - Müller, Ralf
T1 - Internal friction and energy dissipation during fracture in silicate glasses
N2 - To obtain a deeper insight into the nature of energy dissipation during fracture, the internal friction of 13 borosilicate, aluminosilicate, soda-lime, and lead-containing glasses, for which inert crack growth data are known, was measured using dynamic mechanical thermal analysis. For asymmetrically bent glass beams, the loss tangent, tan δ, was determined between 0.2 and 50 Hz at temperatures between 273 K and the glass transition temperature, Tg. It was found that the area under the tan δ vs T·Tg−1 curve correlates with the crack growth exponent, n, in the empirical v = v0·KIn relation between crack growth velocity, v, and stress intensity, KI, which indicates that n correlates with the degree of energy dissipation of sub-Tg relaxation phenomena.
KW - Glass
KW - Internal friction
KW - Crack growth
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-651371
DO - https://doi.org/10.1063/5.0255432
SN - 0021-9606
VL - 162
IS - 19
SP - 1
EP - 9
PB - AIP Publishing
AN - OPUS4-65137
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Pan, Z.
A1 - Waurischk, Tina
A1 - Duval, A.
A1 - Müller, Ralf
A1 - Deubener, J.
A1 - Krishnan, N. M. A.
A1 - Wondraczek, K.
A1 - Wondraczek, L.
T1 - Precise Real‐Time Measurement of Liquid Viscosity Using Digital Video Data
N2 - Quantitative knowledge of liquid viscosity is of fundamental importance in many areas of materials synthesis and processing. However, the determination of viscosity often relies on specialized experimental equipment, offline experimentation, or invasive procedures, in particular when required in extreme conditions such as at high temperature, high pressure, and in confined or corrosive environments. Here, this study proposes and validates a fast and simple method that mimics the intuitive perception of liquid flow within a quantitative framework. For this, this study employs digital video observation to derive quantitative values of the shear viscosity of liquids, with high precision and rapid acquisition rates. The technique involves capturing liquid dynamics after minor mechanical stimulation. Processed imaging data are indexed by similarity and referenced to a digital database generated with a finite element model, from which values of viscosity are obtained in line. The approach is tested on water at room temperature and on a high‐temperature glass melt. Covering a viscosity range of four orders of magnitude, both yield convincing agreement with tabulated reference data at low computational cost.
KW - Glass
KW - Liquid Viscosity
KW - Digital Video Data
KW - Finite Element Method
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-651363
DO - https://doi.org/10.1002/aisy.202500297
SN - 2640-4567
VL - 7
IS - 12
SP - 1
EP - 12
PB - Wiley VHC-Verlag
AN - OPUS4-65136
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Stephan, Jenny
A1 - Stühler, Merlin R.
A1 - Fornacon-Wood, Christoph
A1 - Dimde, Mathias
A1 - Ludwig, Kai
A1 - Sturm, Heinz
A1 - Olmedo-Martínez, Jorge L.
A1 - Müller, Alejandro J.
A1 - Plajer, Alex J.
T1 - Sulfur-containing block polymers from ring-opening copolymerization: coordinative encapsulants for transition metals
N2 - Sulfur-containing polymers can coordinate transition metals via sulfur-centered, chemically soft lone pairs, although this typically occurs in a spatially uncontrolled manner. In this study, we employed the controlled ring-opening copolymerization of oxetane with sulfur-containing comonomers to construct a series of amphiphilic block copolymers featuring thioester and thiocarbonate functionalities. These copolymers self-assemble in aqueous solution into aggregates with a sulfur-rich core capable of coordinating transition metals. This behavior could be resolved by employing cryo-transmission electron tomography and then extended to complexes incorporating functional coligands. Our study demonstrates how selective catalysis can be harnessed to produce functional polymers with tunable metal coordination properties, paving the way for an emerging class of sulfur-containing copolymers.
KW - Sulfur-containing polymer
KW - Controlled synthesis
KW - Metal ion coordination
KW - Cryo TEM
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-626157
DO - https://doi.org/10.1039/d4py01415d
SN - 1759-9962
VL - 16
IS - 8
SP - 1003
EP - 1009
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-62615
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -