TY - JOUR
A1 - Abusafia, A.
A1 - Scheid, C.
A1 - Meurer, Maren
A1 - Altmann, Korinna
A1 - Dittmer, U.
A1 - Steinmetz, H.
T1 - Microplastic sampling strategies in urban drainage systems for quantification of urban emissions based on transport pathways
N2 - Tracking waterborne microplastic (MP) in urban areas is a challenging task because of the various sources and transport pathways involved. Since MP occurs in low concentrations in most wastewater and stormwater streams, large sample volumes need to be captured, prepared, and carefully analyzed. The recent research in urban areas focused mainly on MP emissions at wastewater treatment plants (WWTPs), as obvious entry points into receiving waters. However, important transport pathways under wet-weather conditions are yet not been investigated thoroughly. In addition, the lack of comprehensive and comparable sampling strategies complicated the attempts for a deeper understanding of occurrence and sources. The goal of this paper is to (i) introduce and describe sampling strategies for MP at different locations in a municipal catchment area under dry and wet-weather conditions, (ii) quantify MP emissions from the entire catchment and two other smaller ones within the bigger catchment, and (iii) compare the emissions under dry and wet-weather conditions. WWTP has a high removal rate of MP (>96%), with an estimated emission rate of 189 kg/a or 0.94 g/[population equivalents (PEQ · a)], and polyethylene (PE) as the most abundant MP. The specific dry-weather emissions at a subcatchment were ≈30 g/(PEQ · a) higher than in the influent of WWTP with 23 g/(PEQ · a). Specific wet-weather emissions from large sub-catchment with higher traffic and population densities were 1952 g/(ha · a) higher than the emissions from smaller catchment (796 g/[ha · a]) with less population and traffic. The results suggest that wet-weather transport pathways are likely responsible for 2–4 times more MP emissions into receiving waters compared to dry-weather ones due to tire abrasion entered from streets through gullies. However, more investigations of wet-weather MP need to be carried out considering additional catchment attributes and storm event characteristics.
KW - Combined sewer system
KW - Large volume samplers
KW - Microplastic pollution
KW - Separate sewer system
KW - Stormwater retention tank
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568271
DO - https://doi.org/10.1002/appl.202200056
SP - 1
EP - 12
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-56827
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Accorsi, M.
A1 - Tiemann, M.
A1 - Wehrhan, L.
A1 - Finn, Lauren M.
A1 - Cruz, R.
A1 - Rautenberg, Max
A1 - Emmerling, Franziska
A1 - Heberle, J.
A1 - Keller, B. G.
A1 - Rademann, J.
T1 - Pentafluorophosphato-Phenylalanines: Amphiphilic Phosphotyrosine Mimetics Displaying Fluorine-Specific Protein Interactions
N2 - Phosphotyrosine residues are essential functional switches in health and disease. Thus, phosphotyrosine biomimetics are crucial for the development of chemical tools and drug molecules. We report here the discovery and investigation of pentafluorophosphato amino acids as novel phosphotyrosine biomimetics. A mild acidic pentafluorination protocol was developed and two PF5-amino acids were prepared and employed in peptide synthesis. Their structures, reactivities, and fluorine-specific interactions were studied by NMR and IR spectroscopy, X-ray diffraction, and in bioactivity assays. The mono-anionic PF5 motif displayed an amphiphilic character binding to hydrophobic surfaces, to water molecules, and to protein-binding sites, exploiting charge and H−F-bonding interactions. The novel motifs bind 25- to 30-fold stronger to the phosphotyrosine binding site of the protein tyrosine phosphatase PTP1B than the best current biomimetics, as rationalized by computational methods, including molecular dynamics simulations.
KW - Chemical Biology
KW - Drug Development
KW - Pentafluorophosphates
KW - Phosphotyrosine Biomimetics
KW - Protein Tyrosine Phosphatases
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-549984
DO - https://doi.org/10.1002/anie.202203579
SN - 1433-7851
VL - 134
IS - 25
SP - 1
EP - 6
PB - Wiley-VCH GmbH
AN - OPUS4-54998
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Afantitis, A.
A1 - Melagraki, G.
A1 - Isigonis, P.
A1 - Tsoumanis, A.
A1 - Varsou, D. D.
A1 - Valsami-Jones, E.
A1 - Papadiamantis, A.
A1 - Ellis, L.-J. A.
A1 - Sarimveis, H.
A1 - Doganis, P.
A1 - Karatzas, P.
A1 - Tsiros, P.
A1 - Liampa, I.
A1 - Lobaskin, V.
A1 - Greco, D.
A1 - Serra, A.
A1 - Kinaret, P. A. S.
A1 - Saarimäki, L. A.
A1 - Grafström, R.
A1 - Kohonen, P.
A1 - Nymark, P.
A1 - Willighagen, E.
A1 - Puzyn, T.
A1 - Rybinska-Fryca, A.
A1 - Lyubartsev, A.
A1 - Jensen, K. A.
A1 - Brandenburg, J. G.
A1 - Lofts, S.
A1 - Svendsen, C.
A1 - Harrison, S.
A1 - Maier, D.
A1 - Tamm, K.
A1 - Jänes, J.
A1 - Sikk, L.
A1 - Dusinska, M.
A1 - Longhin, E.
A1 - Rundén-Pran, E.
A1 - Mariussen, E.
A1 - El Yamani, N.
A1 - Unger, Wolfgang
A1 - Radnik, Jörg
A1 - Tropsha, A.
A1 - Cohen, Y.
A1 - Lesczynski, J.
A1 - Hendren, C. O.
A1 - Wiesner, M.
A1 - Winkler, D.
A1 - Suzuki, N.
A1 - Yoon, T. H.
A1 - Choi, J.-S.
A1 - Sanabria, N.
A1 - Gulumian, M.
A1 - Lynch, I.
T1 - NanoSolveIT Project: Driving nanoinformatics research to develop innovative and integrated tools for in silico nanosafety assessment
N2 - Nanotechnology has enabled the discovery of a multitude of novel materials exhibiting unique physicochemical (PChem) properties compared to their bulk analogues. These properties have led to a rapidly increasing range of commercial applications; this, however, may come at a cost, if an association to long-term health and environmental risks is discovered or even just perceived. Many nanomaterials (NMs) have not yet had their potential adverse biological effects fully assessed, due to costs and time constraints associated with the experimental assessment, frequently involving animals. Here, the available NM libraries are analyzed for their suitability for integration with novel nanoinformatics approaches and for the development of NM specific Integrated Approaches to Testing and Assessment (IATA) for human and environmental risk assessment, all within the NanoSolveIT cloud-platform. These established and well-characterized NM libraries (e.g. NanoMILE, NanoSolutions, NANoREG, NanoFASE, caLIBRAte, NanoTEST and the Nanomaterial Registry (>2000 NMs)) contain physicochemical characterization data as well as data for several relevant biological endpoints, assessed in part using harmonized Organisation for Economic Co-operation and Development (OECD) methods and test guidelines.
Integration of such extensive NM information sources with the latest nanoinformatics methods will allow NanoSolveIT to model the relationships between NM structure (morphology), properties and their adverse effects and to predict the effects of other NMs for which less data is available. The project specifically addresses the needs of regulatory agencies and industry to effectively and rapidly evaluate the exposure, NM hazard and risk from nanomaterials and nano-enabled products, enabling implementation of computational ‘safe-by-design’ approaches to facilitate NM commercialization.
KW - Nanoinformatics
KW - Hazard assessment
KW - (Quantitative) Structure-Active Relationships
KW - Safe-by-design
KW - Predictive modelling
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-505952
DO - https://doi.org/10.1016/j.csbj.2020.02.023
VL - 18
SP - 583
EP - 602
PB - Elsevier B.V.
AN - OPUS4-50595
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Agostini, G.
A1 - Radnik, Jörg
T1 - Spectroscopy in Catalysis
N2 - Knowledge-based catalyst development is always an interaction between preparation, analysis and catalytic testing. Only if these three factors fit together can success be expected. For the analytic side of this triangle, spectroscopic methods play a crucial role. Whereas with diffraction, scattering and microscopy, decisive insights into the structure and morphology of the catalysts can be obtained, spectroscopy produces new knowledge about the chemical nature of the catalyst, e.g., its bonding and valence states.
KW - Spectroscopy
KW - Catalysis
KW - Operando
KW - In situ
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506507
DO - https://doi.org/10.3390/catal10040408
VL - 10
IS - 4
SP - 408
PB - MDPI
CY - Basel
AN - OPUS4-50650
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Ahmed, R.
A1 - Vaishampayan, A.
A1 - Cuellar-Camacho, J. L.
A1 - Wight, D. J.
A1 - Donskyi, Ievgen
A1 - Unger, Wolfgang
A1 - Grohmann, E.
A1 - Haag, R.
A1 - Wagner, O.
T1 - Multivalent Bacteria Binding by Flexible Polycationic Microsheets Matching Their Surface Charge Density
N2 - Aiming at the overall negative surface charge of bacteria, a new strategy of antibacterial agents based on large polymer-modified graphene oxide (GO) sheets is assessed. The presented flexible, polycationic Sheets match the size and charge density of the Escherichia coli surface charge density (2 × 1014 cm−2). These matching parameters create an unspecific but very strong bacteria adsorber by multivalent, electrostatic attraction.
Their interaction with bacteria is visualized via atomic force and confocal microscopy and shows that they effectively bind and wrap around E. coli cells, and thereby immobilize them. The incubation of Gram-negative and -positive bacteria (E. coli and methicillin-resistant Staphylococcus aureus, MRSA) with these polycationic sheets leads to the inhibition of proliferation and a reduction of the colony forming bacteria over time.
This new type of antibacterial agent acts in a different mode of Action than classical biocides and could potentially be employed in medicinal, technical, or agriculture applications. The presented microsheets and their unspecific binding of cell interfaces could further be employed as adsorber material for bacterial filtration or immobilization for imaging, analysis, or sensor technologies.
KW - Surface charge
KW - Bacteria
KW - Graphene oxide
KW - Escherichia coli
KW - XPS
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509651
DO - https://doi.org/10.1002/admi.201902066
VL - 7
IS - 15
SP - 1902066
PB - WILEY-VCH Verlag GmbH & Co. KGaA
CY - Weinheim
AN - OPUS4-50965
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Akbar, S.
A1 - Hasanain, S.K.
A1 - Ivashenko, O.
A1 - Dutka, M.V.
A1 - Akhtar, N.
A1 - De Hosson, J.Th.M.
A1 - Ali, Naveed
A1 - Rudolf, P.
T1 - Defect ferromagnetism in SnO2:Zn2+ hierarchical nanostructures: correlation between structural, electronic and magnetic properties
N2 - We report on the ferromagnetism of Sn1-xZnxO2 (x < 0.1) hierarchical nanostructures with various morphologies synthesized by a solvothermal route. A room temperature ferromagnetic and paramagnetic response was observed for all compositions, with a maximum in ferromagnetism for x = 0.04. The ferromagnetic behaviour was found to correlate with the presence of zinc on substitutional Sn sites and with a low oxygen vacancy concentration in the samples. The morphology of the nanostructures varied with zinc concentration. The strongest ferromagnetic response was observed in nanostructures with well-formed shapes, having nanoneedles on their surfaces. These nanoneedles consist of (110) and (101) planes, which are understood to be important in stabilizing the ferromagnetic defects. At higher zinc concentration the nanostructures become eroded and agglomerated, a phenomenon accompanied with a strong decrease in their ferromagnetic response. The observed trends are explained in the light of recent computational studies that discuss the relative stability of ferromagnetic defects on various surfaces and the role of oxygen vacancies in degrading ferromagnetism via an increase in free electron concentration.
KW - Ferromagnetism
KW - Nanostructures
KW - Magnetic properties
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-473014
DO - https://doi.org/10.1039/c9ra00455f
SN - 2046-2069
VL - 9
IS - 7
SP - 4082
EP - 4091
PB - Royal Society of Chemistry
AN - OPUS4-47301
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Aliyah, K.
A1 - Prehal, C.
A1 - Diercks, J. S.
A1 - Diklić, N.
A1 - Xu, L.
A1 - Ünsal, S.
A1 - Appel, C.
A1 - Pauw, Brian Richard
A1 - Smales, Glen Jacob
A1 - Guizar-Sicairos, M.
A1 - Herranz, J.
A1 - Gubler, L.
A1 - Büchi, F. N.
A1 - Eller, J.
T1 - Quantification of PEFC Catalyst Layer Saturation via In Silico, Ex Situ, and In Situ Small-Angle X-ray Scattering
N2 - The complex nature of liquid water saturation of polymer electrolyte fuel cell (PEFC) catalyst layers (CLs) greatly affects the device performance. To investigate this problem, we present a method to quantify the presence of liquid water in a PEFC CL using small-angle X-ray scattering (SAXS). This method leverages the differences in electron densities between the solid catalyst matrix and the liquid water filled pores of the CL under both dry and wet conditions. This approach is validated using ex situ wetting experiments, which aid the study of the transient saturation of a CL in a flow cell configuration in situ. The azimuthally integrated scattering data are fitted using 3D morphology models of the CL under dry conditions. Different wetting scenarios are realized in silico, and the corresponding SAXS data are numerically simulated by a direct 3D Fourier transformation. The simulated SAXS profiles of the different wetting scenarios are used to interpret the measured SAXS data which allows the derivation of the most probable wetting mechanism within a flow cell electrode.
KW - Polymer electrolyte fuel cell
KW - Water management
KW - Catalyst layer
KW - Representative morphology modeling
KW - Small-angle X-ray scattering
KW - MOUSE
KW - SAXS
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575973
DO - https://doi.org/10.1021/acsami.3c00420
SN - 1944-8244
VL - 15
IS - 22
SP - 26538
EP - 26553
PB - ACS Publications
AN - OPUS4-57597
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Almalla, A.
A1 - Hertwig, Andreas
A1 - Fischer, Daniel
A1 - Özcan Sandikcioglu, Özlem
A1 - Witt, Julia
T1 - Development of layer-by-layer assembled thin coatings on aluminium alloy AA2024-T3 for high resolution studies of local corrosion processes
N2 - The aim of this study is to develop nanometer-thin epoxy-based films on aluminium alloy AA2024-T3 as a model coating system for high resolution corrosion studies. Spin coating was used for the layer-by-layer (LbL) deposition of poly-(ethylenimine) (PEI) and poly([o-cresyl glycidyl ether]-co-formaldehyde) (CNER) bilayers. The film chemistry and the cross-linking process were characterized by means of Fourier-transform infrared spectroscopy (FTIR).
Ellipsometric data confirmed the linear increase of film thickness. The potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) results indicate the improvement of the film barrier properties with increasing film thickness. Mapping of the topography and the volta potential was performed by means of scanning Kelvin probe force microscopy (SKPFM).
The results indicate the presence of a homogeneous film structure, while the intermetallic phases can still be identified below the coating. The SKPFM Analysis confirmed that the model films are suitable for investigation of corrosion processes at the coating/metal interface.
KW - Spectroscopy
KW - Coatings
KW - Electrochemistry
KW - Microscopy
KW - Resins
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514627
DO - https://doi.org/10.1002/app.49826
SN - 0021-8995
VL - 137
IS - 48
SP - e49826-1
EP - e49826-9
PB - Wiley
CY - New York, NY
AN - OPUS4-51462
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Almalla, A.
A1 - Özcan Sandikcioglu, Özlem
A1 - Witt, Julia
T1 - In Situ Atomic Force Microscopy Analysis of the Corrosion Processes at the Buried Interface of an Epoxy-like Model Organic Film and AA2024-T3 Aluminum Alloy
N2 - The application of characterization methods with high spatial resolution to the analysis of buried coating/metal interfaces requires the design and use of model systems. Herein, an epoxy-like thin film is used as a model coating resembling the epoxy-based coatings and adhesives widely used in technical applications. Spin coating is used for the deposition of a 30 nm-thin bilayer (BL) composed of poly-(ethylenimine) (PEI) and poly[(o-cresyl glycidyl ether)-co-formaldehyde] (CNER). Fourier-transform infrared spectroscopy (FTIR) results confirm that the exposure of coated AA2024-T3 (AA) samples to the corrosive electrolyte solution does not cause the degradation of the polymer layer. In situ atomic force microscopy (AFM) studies are performed to monitor local corrosion processes at the buried interface of the epoxy-like film and the AA2024-T3 aluminum alloy surface in an aqueous electrolyte solution. Hydrogen evolution due to the reduction of water as the cathodic corrosion reaction leads to local blister formation. Based on the results of the complementary energy-dispersive X-ray spectroscopy (EDX) analysis performed at the same region of interest, most of the hydrogen evolved originates at the vicinity of Mg-containing intermetallic particles.
KW - Scanning Kelvin probe force microscopy
KW - Aluminum alloys
KW - Buried interfaces
KW - In situ atomic force microscopy
KW - Local corrosion
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546932
DO - https://doi.org/10.1002/adem.202101342
SN - 1438-1656
SP - 1
EP - 9
PB - Wiley VHC-Verlag
AN - OPUS4-54693
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Altmann, Korinna
A1 - Goedecke, Caroline
A1 - Bannick, C.-G.
A1 - Abusafia, A.
A1 - Scheid, C.
A1 - Steinmetz, H.
A1 - Paul, Andrea
A1 - Beleites, C.
A1 - Braun, U.
T1 - Identification of microplastic pathways within a typical European urban wastewater system
N2 - In recent years, thermoextraction/desorption-gas chromatography/mass spectrometry (TED-GC/MS) has been developed as a rapid detection method for the determination of microplastics (MP) mass contents in numerous environmentally relevant matrices and, in particular, for the measurement of polymers in water samples without time-consuming sample preparation. The TED-GC/MS method was applied to investigate a typical European municipal wastewater system for possible MP masses. Such investigations are important in view of the recent revision of the Urban Wastewater Treatment Directive. Four different representative sampling sites were selected: greywater (domestic wastewater without toilet), combined sewer, and influent and effluent of a wastewater treatment plant (WWTP). All samples were collected by fractional filtration. Filtration was carried out over mesh sizes of 500, 100, 50, and in some cases, 5 µm. Polyethylene (PE), polypropylene (PP), and polystyrene (PS) were detected in all samples, with the PE fraction dominating in all cases. Styrene-butadiene rubber which serves as an indication of tire abrasion, was only found in the influent of the WWTP. The highest MP mass contents were found in the combined sewer, so MP can become a source of pollution during heavy rain events when the capacity limits of the effluent are reached, and the polluted effluent is released uncontrolled into the environment. Based on the studies, MP retention from the WWTP could be estimated to be approximately 96%. Few trends in polymer type or mass contents were detected within the different fractions of the samples or when comparing samples to each other.
KW - Microplastics
KW - Microplastic analysis
KW - TED-GC/MS
KW - Microplastic pathways
KW - Mass contents
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568289
DO - https://doi.org/doi.org/10.1002/appl.202200078
SP - 1
EP - 10
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-56828
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - An, Biwen Annie
A1 - Kleinbub, Sherin
A1 - Özcan Sandikcioglu, Özlem
A1 - Koerdt, Andrea
T1 - Iron to Gas: Versatile Multiport Flow-Column Revealed Extremely High Corrosion Potential by Methanogen-Induced Microbiologically Influenced Corrosion (Mi-MIC)
N2 - Currently, sulfate-reducing bacteria (SRB) is regarded as the main culprit of microbiologically influenced corrosion (MIC), mainly due to the low reported corrosion rates of other microorganisms. For example, the highest reported corrosion rate for methanogens is 0.065 mm/yr. However, by investigating methanogen-induced microbiologically influenced corrosion (Mi-MIC) using an in-house developed versatile multiport flow test column, extremely high corrosion rates were observed. We analyzed a large set of carbon steel beads, which were sectionally embedded into the test columns as substrates for iron-utilizing methanogen Methanobacterium IM1. After 14 days of operation using glass beads as fillers for section separation, the highest average corrosion rate of Methanobacterium IM1 was 0.2 mm/yr, which doubled that of Desulfovibrio ferrophilus IS5 and Desulfovibrio alaskensis 16109 investigated at the same conditions. At the most corroded region, nearly 80% of the beads lost 1% of their initial weight (fast-corrosion), resulting in an average corrosion rate of 0.2 mm/yr for Methanobacterium IM1-treated columns. When sand was used as filler material to mimic sediment conditions, average corrosion rates for Methanobacterium IM1 increased to 0.3 mm/yr (maximum 0.52 mm/yr) with over 83% of the beads having corrosion rates above 0.3 mm/yr. Scanning electron images of metal coupons extracted from the column showed methanogenic cells were clustered close to the metal surface. Methanobacterium IM1 is a hydrogenotrophic methanogen with higher affinity to metal than H2. Unlike SRB, Methanobacterium IM1 is not restricted to the availability of sulfate concentration in the environment. Thus, the use of the multiport flow column provided a new insight on the corrosion potential of methanogens, particularly in dynamic conditions, that offers new opportunities for monitoring and development of mitigation strategies. Overall, this study shows under certain conditions methanogenic archaea can cause higher corrosion than SRB, specific quantifications, i.e., maximum, average, and minimum corrosion rates can be determined, and that spatial statistical evaluations of MIC can be carried out.
KW - Microbiologically influenced corrosion
KW - Methanogen
KW - Methane
KW - Biocorrosion
KW - Flow system
KW - Modeling
KW - Multiport
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506084
DO - https://doi.org/10.3389/fmicb.2020.00527
VL - 11
SP - Article 527
PB - Frontiers in microbiology
AN - OPUS4-50608
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Aratsu, K.
A1 - Takeya, R.
A1 - Pauw, Brian Richard
A1 - Hollamby, M.J.
A1 - Kitamoto, Y.
A1 - Shimizu, N.
A1 - Takagi, H.
A1 - Haruki, R.
A1 - Adachi, S.
A1 - Yagai, S.
T1 - Supramolecular copolymerization driven by integrative self-sorting of hydrogen-bonded rosettes
N2 - Molecular recognition to preorganize noncovalently polymerizable supramolecular complexes is a characteristic process of natural supramolecular polymers, and such recognition processes allow for dynamic self-alteration, yielding complex polymer systems with extraordinarily high efficiency in their targeted function. We herein show an example of such molecular recognition-controlled kinetic assembly/disassembly processes within artificial supramolecular polymer systems using six-membered hydrogen-bonded supramolecular complexes (rosettes). Electron-rich and poor monomers are prepared that kinetically coassemble through a temperature-controlled protocol into amorphous coaggregates comprising a diverse mixture of rosettes. Over days, the electrostatic interaction between two monomers induces an integrative self-sorting of rosettes. While the electron-rich monomer inherently forms toroidal homopolymers, the additional electrostatic interaction that can also guide rosette association allows helicoidal growth of supramolecular copolymers that are comprised of an alternating array of two monomers. Upon heating, the helicoidal copolymers undergo a catastrophic transition into amorphous coaggregates via entropy-driven randomization of the monomers in the rosette.
KW - Self-assembly
KW - Coaggregation
KW - Scattering
KW - Simulation
KW - AFM
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506555
DO - https://doi.org/10.1038/s41467-020-15422-6
VL - 11
IS - 1
SP - Article number: 1623
PB - Springer Nature
AN - OPUS4-50655
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Arinchtein, A.
A1 - Ye, M.-Y.
A1 - Yang, Q.
A1 - Kreyenschulte, C.
A1 - Wagner, Andreas
A1 - Frisch, M.
A1 - Brückner, A.
A1 - Kondratenko, E.
A1 - Kraehnert, R.
T1 - Dynamics of Reaction-Induced Changes of Model-Type Iron Oxide Phases in the CO2-Fischer-Tropsch-Synthesis
N2 - Iron-based catalysts are employed in CO2-FTS due to their ability to convert CO2 into CO in a first step and their selectivity towards higher hydrocarbons in a second CO hydrogenation step. According to the literature, iron carbides represent the active phase for hydrocarbon formation and are claimed to emerge in the presence of CO. We propose nanostructured FeOx films as model systems to assess information about the complex phase transformations during CO2-FTS. Mesoporous hematite, ferrihydrite, maghemite, maghemite/magnetite films were exposed to CO2-FTS atmospheres at 20 bar and 300°C. Up to three distinct phases were observed depending on the timeon-stream (TOS): a sintered maghemite/magnetite phase, a carbidic core-shell structure, and a low-crystalline, needle-type oxide phase. Our findings indicate that the formation of an intermediary maghemite/magnetite phase, predominant after short TOS (30 h), precedes the evolution of the carbide phase.
Yet, even after prolonged TOS (185 h), no full conversion into a bulk carbide is observed.
KW - Nanostructured FeOx films
KW - CO2
KW - Scanning Auger Spectroscopy
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-549709
DO - https://doi.org/10.1002/cctc.202200240
SN - 1867-3880
VL - 14
IS - 14
SP - 1
EP - 11
PB - Wiley-VCH
AN - OPUS4-54970
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Arnold, M.
A1 - Katzmann, J.
A1 - Naik, Aakash Ashok
A1 - Görne, A. L.
A1 - Härtling, Thomas
A1 - George, Janine
A1 - Schuster, C.
T1 - Investigations on electron beam irradiated rare-earth doped SrF2 for application as low fading dosimeter material: Evidence for and DFT simulation of a radiation-induced phase
N2 - A recent approach to measure electron radiation doses in the kGy range is the use of phosphors with an irradiation dose-dependent luminescence decay time. However, the applicability of the previously investigated material NaYF4:Yb3+,Er3+ is limited as it shows pronounced fading. Therefore, in this work, a modified SrF2 synthesis is presented that results in SrF2 nanoparticles codoped with Yb and either Er, Hm, or Tm. To assess their suitability as dosimeter material, dose response, as well as its degree of fading over 50 up to 140 days after irradiation were measured. Fading rates as small as 5% in SrF2:Er,Yb and 4% in SrF2:Ho,Yb were derived, which are comparable to established dosimeter materials. A combination of spectroscopy, diffraction and DFT calculations was used to elucidate the effect of irradiation, pointing towards the formation of a secondary phase of Yb2+ that we predict could be Yb2OF2. This irreversible formation of a secondary phase is considered to be the explanation for the low fading behavior in SrF2-based phosphors compared to NaYF4:Yb, Er, a highly attractive feature for electron beam dosimetry.
KW - DFT
KW - Structure prediction
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-554115
DO - https://doi.org/10.1039/D2TC01773C
SN - 2050-7526
VL - 10
IS - 32
SP - 11579
EP - 11587
PB - RSC
CY - London
AN - OPUS4-55411
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Babutzka, Martin
A1 - Grabowski, Sven
A1 - Sahrhage, H.
A1 - Lampke, T.
T1 - Electrochemical corrosion investigations on binary and ternary zinc alloy coatings using gel electrolytes
N2 - Novel agar-based test electrolytes are used to perform electrochemical corrosion investigations on ZnFe and ZnNi binary as well as ZnFeMo ternary zinc coatings. The objectives of the electrochemical investigations include the characterization of the corrosion behavior, the description of the protective effect of the coatings as well as the investigation of the layer formation and degradation under artificial aging. ZnFe and ZnFeMo coatings are applied with varying iron content as well as an additional passivation layer, respectively, to study the effect on corrosion resistance. The results show that the protective effect of the coatings is not negatively influenced by different iron contents or the addition of molybdenum. Additional passivation of the ZnFe-containing coatings by means of a passivating agent leads to a significant improvement in the protective effect. Artificial aging leads to slight degradation of the additional passivation layer whereas coatings without post-treatment enhance their protective effect by the formation of corrosion product layers.
KW - Binary zinc alloys
KW - Ternary zinc alloys
KW - Corrosion testing
KW - Gel electrolytes
KW - Corrosion
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543013
DO - https://doi.org/10.1002/adem.202101336
SN - 1438-1656
SP - 1
EP - 14
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54301
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Battig, Alexander
A1 - Müller, Patrick
A1 - Bertin, Annabelle
A1 - Schartel, Bernhard
T1 - Hyperbranched Rigid Aromatic Phosphorus-Containing Flame Retardants for Epoxy Resins
N2 - A rigid aromatic phosphorus-containing hyperbranched flame retardant structure is synthesized from 10-(2,5 dihydroxyphenyl)-10H-9-oxa-
10-phosphaphenanthrene-10-oxide (DOPO-HQ), tris(4-hydroxyphenyl)phosphine oxide (THPPO), and 1,4-terephthaloyl chloride (TPC). The resulting poly-(DOPO-HQ/THPPO-terephthalate) (PDTT) is implemented as a flame retardant into an epoxy resin (EP) at a 10 wt% loading. The effects on EP are compared with those of the monomer DOPO-HQ and triphenylphosphine oxide (OPPh3) as low molar mass flame retardants. The glass transition temperature, thermal decomposition, flammability (reaction to small flame), and burning behavior of the thermosets are investigated using differential scanning calorimetry, thermogravimetric analysis, pyrolysis combustion flow calorimetry, UL 94-burning chamber testing, and cone calorimeter measurements.
Although P-contents are low at only 0.6 wt%, the study aims not at attaining V-0, but at presenting a proof of principle: Epoxy resinswith PDTT show promising fire performance, exhibiting a 25% reduction in total heat evolved (THE), a 30% reduction in peak heat release rate (PHRR) due to flame inhibition (21% reduction in effective heat of combustion (EHC)), and an increase in Tg at the same time. This study indicates that rigid aromatic hyperbranched polymeric structures offer a promising route toward multifunctional flame retardancy.
KW - Hyperbranched
KW - Aromatic
KW - Phosphorus
KW - Phosphine oxide
KW - DOPO
KW - Flame retardant
KW - Xpoxy resin
KW - Rigid
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525910
DO - https://doi.org/10.1002/mame.202000731
SN - 1439-2054
VL - 306
IS - 4
SP - 731
PB - Wiley
AN - OPUS4-52591
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bawadkji, O.
A1 - Cherri, M.
A1 - Schäfer, A.
A1 - Herziger, S.
A1 - Nickl, Philip
A1 - Achazi, K.
A1 - Donskyi, Ievgen
A1 - Adeli, M.
A1 - Haag, R.
T1 - One-pot covalent functionalization of 2D black phosphorus by anionic ring opening polymerization
N2 - In this work, a one-pot approach for the covalent functionalization of few-layer black phosphorus (BP) by anionic ring opening polymerization of glycidol to obtain multifunctional BP-polyglycerol (BP-PG) with high amphiphilicity for near-infrared-responsive drug delivery and biocompatibility is reported. Straightforward synthesis in combination with exceptional biological and physicochemical properties designates functionalized BP-PG as a promising candidate for a broad range of biomedical applications.
KW - 2D nanomaterial
KW - Amphiphilicity
KW - Black phosphorus
KW - Hyperbranched
KW - Polyglycerol
KW - Water dispersibility
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568833
DO - https://doi.org/10.1002/admi.202201245
SN - 2196-7350
VL - 9
SP - 1
EP - 8
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-56883
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Belenguer, A.
A1 - Lampronti, G.
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
A1 - Sanders, J.
T1 - Quantitative reversible one pot interconversion of three crystalline polymorphs by ball mill grinding
N2 - We demonstrate here using a disulfide system the first example of reversible, selective, and quantitative transformation between three crystalline polymorphs by ball mill grinding. This includes the discovery of a previously unknown polymorph. Each polymorph is reproducibly obtained under well-defined neat or liquid-assisted grinding conditions, revealing subtle control over the apparent thermodynamic stability. We discovered that the presence of a contaminant as low as 1.5% mol mol−1 acting as a template is required to enable all these three polymorph transformations. The relative stabilities of the polymorphs are determined by the sizes of the nanocrystals produced under different conditions and by surface interactions with small amounts of added solvent. For the first time, we show evidence that each of the three polymorphs is obtained with a unique and reproducible crystalline size. This mechanochemical approach gives access to bulk quantities of metastable polymorphs that are inaccessible through recrystallisation.
KW - Mechanochemistry
KW - Polymorph
KW - XRD
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-549934
DO - https://doi.org/10.1039/D2CE00393G
SP - 1
EP - 7
PB - Royal Society of Chemistry
AN - OPUS4-54993
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Belenguer, A.
A1 - Michalchuk, Adam
A1 - Lampronti, G
A1 - Sanders, J
T1 - Understanding the unexpected effect of frequency on the kinetics of a covalent reaction under ball-milling conditions
N2 - We here explore how ball-mill-grinding frequency affects the kinetics of a disulfide exchange reaction. Our kinetic data show that the reaction progress is similar at all the frequencies studied (15–30 Hz), including a significant induction time before the nucleation and growth process starts. This indicates that to start the reaction an initial energy accumulation is necessary. Other than mixing, the energy supplied by the mechanical treatment has two effects: (i) reducing the crystal size and (ii) creating defects in the structure. The crystal-breaking process is likely to be dominant at first becoming less important later in the process when the energy supplied is stored at the molecular level as local crystal defects. This accumulation is taken here to be the rate-determining step. We suggest that the local defects accumulate preferentially at or near the crystal surface. Since the total area increases exponentially when the crystal size is reduced by the crystal-breaking process, this can further explain the exponential dependence of the onset time on the milling frequency.
KW - Mechanochemistry
KW - Kinetics
KW - Diffraction
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-483361
DO - https://doi.org/10.3762/bjoc.15.120
SN - 2195-951X
VL - 15
SP - 1226
EP - 1235
PB - Beilstein-Institut zur Förderung der Chemischen Wissenschaften
CY - Frankfurt, M.
AN - OPUS4-48336
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bennet, Francesca
A1 - Burr, L.
A1 - Schmid, D.
A1 - Hodoroaba, Vasile-Dan
T1 - Towards a method for quantitative evaluation of nanoparticle from suspensions via microarray printing and SEM analysis
N2 - As part of the development of a library of accurate and efficient methods for measurement of nanoparticle properties, we develop and optimize a method for the efficient analysis of nanoparticle size distribution from suspensions via microprinting and digital analysis of electron microscopy (SEM and TEM) images, with the ultimate aim of automated quantitative concentration analysis (calculated from drop volume). A series of different nanoparticle suspensions (gold, latex, and SiO2 in varying sizes and concentrations) were printed onto TEM grids in a 4 x 4 array in the concentration range 7x10^8 to 1x10^11 nanoparticles/mL and imaged with SEM. Concentrations and printing conditions (temperature, relative humidity) were varied in order to minimize the coffee-ring effect.
KW - Nanoparticles
KW - Particle size distribution
KW - Electron microscopy
KW - Microarray printing
KW - Sample preparation
KW - Nanoparticle concentration
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528455
DO - https://doi.org/10.1088/1742-6596/1953/1/012002
VL - 1953
SP - 012002
PB - IOP Publishing
AN - OPUS4-52845
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bennet, Francesca
A1 - Müller, Anja
A1 - Radnik, Jörg
A1 - Hachenberger, Y.
A1 - Jungnickel, H.
A1 - Laue, P.
A1 - Luch, A.
A1 - Tentschert, J.
T1 - Preparation of Nanoparticles for ToF-SIMS and XPS Analysis
N2 - Nanoparticles have gained increasing attention in recent years due to their potential and application in different fields including medicine, cosmetics, chemistry, and their potential to enable advanced materials. To effectively understand and regulate the physico-chemical properties and potential adverse effects of nanoparticles, validated measurement procedures for the various properties of nanoparticles need to be developed. While procedures for measuring nanoparticle size and size Distribution are already established, standardized methods for analysis of their surface chemistry are not yet in place, although the influence of the surface chemistry on nanoparticle properties is undisputed. In particular, storage and preparation of nanoparticles for surface analysis strongly influences the analytical results from various methods, and in order to obtain consistent results, sample preparation must be both optimized and standardized. In this contribution, we present, in detail, some standard procedures for preparing nanoparticles for surface analytics. In principle, nanoparticles can be deposited on a suitable substrate from suspension or as a powder. Silicon (Si) Wafers are commonly used as substrate, however, their cleaning is critical to the process. For sample preparation from suspension, we will discuss drop-casting and spin-coating, where not only the cleanliness of the substrate and purity of the suspension but also its concentration play important roles for the success of the preparation methodology.
For nanoparticles with sensitive ligand shells or coatings, deposition as powders is more suitable, although this method requires particular care in fixing the sample.
KW - Titania nanoparticles
KW - X-ray photoelectron spectroscopy
KW - Secondary ion mass spectrometry
KW - Surface chemisttry
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520103
UR - https://www.jove.com/video/61758
DO - https://doi.org/10.3791/61758
VL - 163
SP - e61758
AN - OPUS4-52010
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bennet, Francesca
A1 - Opitz, R.
A1 - Ghoreishi, N.
A1 - Plate, K.
A1 - Barnes, J.-P.
A1 - Bellew, A.
A1 - Bellu, A.
A1 - Ceccone, G.
A1 - de Vito, E.
A1 - Delcorte, A.
A1 - Franquet, A.
A1 - Fumageli, F.
A1 - Gilliland, D.
A1 - Jungnickel, H.
A1 - Lee, T.G.
A1 - Poleunis, C.
A1 - Rading, D.
A1 - Shon, H.K.
A1 - Spampinato, V.
A1 - Son, J.G.
A1 - Wang, F.
A1 - Wang, Y.-C. A.
A1 - Zhao, Y.
A1 - Roloff, A.
A1 - Tentschert, J.
A1 - Radnik, Jörg
T1 - VAMAS TWA2 interlaboratory comparison: Surface analysis of TiO2 nanoparticles using ToF-SIMS
N2 - Due to the extremely high specific surface area of nanoparticles and corresponding potential for adsorption, the results of surface analysis can be highly dependent on the history of the particles, particularly regarding sample preparation and storage. The sample preparation method has, therefore, the potential to have a significant influence on the results. This report describes an interlaboratory comparison (ILC) with the aim of assessing which sample preparation methods for ToF-SIMS analysis of nanoparticles provided the most intra- and interlaboratory consistency and the least amount of sample contamination. The BAM reference material BAM-P110 (TiO2 nanoparticles with a mean Feret diameter of 19 nm) was used as a sample representing typical nanoparticles. A total of 11 participants returned ToF-SIMS data,in positive and (optionally) negative polarity, using sample preparation methods of “stick-and-go” as well as optionally “drop-dry” and “spin-coat.” The results showed that the largest sources of variation within the entire data set were caused by adventitious hydrocarbon contamination or insufficient sample coverage, with the spin-coating protocol applied in this ILC showing a tendency toward insufficient sample coverage; the sample preparation method or the participant had a lesser influence on results.
KW - Secondary Ion Mass Spectrometry
KW - VMAAS
KW - Titania
KW - Interlaboratory comparison
KW - Reproducibility
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-582290
DO - https://doi.org/10.1116/6.0002814
SN - 0734-2101
VL - 41
IS - 5
SP - 053210-1
EP - 053210-13
PB - AIP (American Institute of Physics)
AN - OPUS4-58229
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bernges, T.
A1 - Hanus, R.
A1 - Wankmiller, B.
A1 - Imasato, K.
A1 - Lin, S.
A1 - Ghidiu, M.
A1 - Gerlitz, M.
A1 - Peterlechner, M.
A1 - Graham, S.
A1 - Hautier, G.
A1 - Pei, Y.
A1 - Hansen, M. R.
A1 - Wilde, G.
A1 - Snyder, G. J.
A1 - George, Janine
A1 - Agne, M T.
A1 - Zeier, W. G.
T1 - Considering the Role of Ion Transport in Diffuson-Dominated Thermal Conductivity
N2 - Next-generation thermal management requires the development of low lattice thermal conductivity materials, as observed in ionic conductors. For example, thermoelectric efficiency is increased when thermal conductivity is decreased. Detrimentally, high ionic conductivity leads to thermoelectric device degradation. Battery safety and design also require an understanding of thermal transport in ionic conductors. Ion mobility, structural complexity, and anharmonicity have been used to explain the thermal transport properties of ionic conductors. However, thermal and ionic transport are rarely discussed in direct comparison. Herein, the ionic conductivity of Ag+ argyrodites is found to change by orders of magnitude without altering the thermal conductivity. Thermal conductivity measurements and two-channel lattice dynamics modeling reveal that the majority of Ag+ vibrations have a non-propagating diffuson-like character, similar to amorphous materials. It is found that high ionic mobility is not a requirement for diffuson-mediated transport. Instead, the same bonding and structural traits that can lead to fast ionic conduction also lead to diffuson-mediated transport. Bridging the fields of solid-state ionics and thermal transport, it is proposed that a vibrational perspective can lead to new design strategies for functional ionic conducting materials. As a first step, the authors relate the so-called Meyer-Neldel behavior in ionic conductors to phonon occupations.
KW - Diffusons
KW - DFT
KW - Phonons
KW - Thermoelectrics
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547140
DO - https://doi.org/10.1002/aenm.202200717
SN - 1614-6832
VL - 12
IS - 22
SP - 1
EP - 13
PB - Wiley VHC-Verlag
AN - OPUS4-54714
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Beyer, Sebastian
A1 - Schürmann, Robin
A1 - Feldmann, Ines
A1 - Blocki, A.
A1 - Bald, Ilko
A1 - Schneider, Rudolf
A1 - Emmerling, Franziska
T1 - Maintaining Stable Zeolitic Imidazolate Framework (ZIF) Templates during Polyelectrolyte Multilayer Coating
N2 - Equipping ZIF particles with a polyelectrolyte membrane provides functional groups at their interface, enabling further conjugations necessary for applications such as targeted drug delivery. Previous approaches to coat ZIF particles with polyelectrolytes led to surface corrosion of the template material. This work overcomes previous limitations by performing a Layer-by-Layer (LbL) polyelectrolyte coating onto ZIF-8 and ZIF-67 particles in nonaqueous environment. Using the 2-methylimidazolium salt of polystyrensulfonic acid instead of the acid itself and polyethyleneimine in methanol led to intact ZIF particles after polyelectrolyte coating. This was verified by electron microscopy. Further, zetapotential and atomic force microscopy measurements confirmed a continuous polyelectrolyte multilayer built up. The here reported adaption to the well-studied (LbL) polyelectrolyte selfassembly process provides a facile method to equip ZIF particles with a nanometer thin polyelectrolyte multilayer membrane.
KW - Zeolithe
KW - Molecular Organic Frameworks
KW - MOF
KW - ZIF
KW - Layer-by-Layer
KW - Beschichtung
KW - Polyelektrolyt
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-447729
DO - https://doi.org/10.1016/j.colcom.2017.11.004
SN - 2215-0382
VL - 22
SP - 14
EP - 17
PB - Elsevier B.V.
CY - Amsterdam, NL
AN - OPUS4-44772
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam A. L.
A1 - Silbernagl, Dorothee
A1 - Yasuda, N.
A1 - Feiler, Torvid
A1 - Sturm, Heinz
A1 - Emmerling, Franziska
T1 - An atomistic mechanism for elasto-plastic bending in molecular crystals
N2 - Mechanically flexible single crystals of molecular materials offer potential for a multitude of new directions in advanced materials design. Before the full potential of such materials can be exploited, insight into their mechanisms of action must be better understood. Such insight can be only obtained through synergistic use of advanced experimentation and simulation. We herein report the first detailed mechanistic study of elasto-plastic flexibility in a molecular solid. An atomistic origin for this mechanical behaviour is proposed through a combination of atomic force microscopy, μ-focus synchrotron X-ray diffraction, Raman spectroscopy, ab initio simulation, and computed elastic tensors. Our findings suggest that elastic and plastic bending are intimately linked and result from extensions of the same molecular deformations. The proposed mechanism bridges the gap between contested mechanisms, suggesting its applicability as a general mechanism for elastic and plastic bending in organic molecular crystals.
KW - Mechanical property
KW - Mechanical flexibility
KW - Organic crystal
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-577722
DO - https://doi.org/10.1039/D2SC06470G
SN - 2041-6520
VL - 14
IS - 13
SP - 3441
EP - 3450
PB - Royal Society of Chemisty (RSC)
CY - London/Cambridge
AN - OPUS4-57772
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Silbernagl, Dorothee
A1 - Rautenberg, Max
A1 - Schmid, Thomas
A1 - Feiler, Torvid
A1 - Reimann, K.
A1 - Ghalgaoui, A.
A1 - Sturm, Heinz
A1 - Paulus, B.
A1 - Emmerling, Franziska
T1 - A Mechanistic Perspective on Plastically Flexible Coordination Polymers
N2 - Mechanical flexibility in single crystals of covalently bound materials is a fascinating and poorly understood phenomenon. We present here the first example of a plastically flexible one-dimensional (1D) coordination polymer. The compound [Zn(m-Cl)2(3,5-dichloropyridine)2]n is flexible over two crystallographic faces. Remarkably, the single crystal remains intact when bent to 1808. A combination of microscopy, diffraction, and spectroscopic studies have been used to probe the structural response of the crystal lattice to mechanical bending. Deformation of the covalent polymer chains does not appear to be responsible for the observed macroscopic bending. Instead, our results suggest that mechanical bending occurs by displacement of the coordination polymer chains. Based on experimental and theoretical evidence, we propose a new model for mechanical flexibility in 1D coordination polymers. Moreover, our calculations propose a cause of the different mechanical properties of this compound and a structurally similar elastic material
KW - Coordination polymer
KW - Flexible crystals
KW - Mechanical properties
KW - Plastic deformation
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504755
DO - https://doi.org/10.1002/anie.201914798
VL - 59
IS - 14
SP - 5557
EP - 5561
PB - Wiley-VCH
AN - OPUS4-50475
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bonse, Jörn
T1 - Quo vadis LIPSS? - Recent and future trends on laser-induced periodic surface structures
N2 - Nanotechnology and lasers are among the most successful and active fields of research and technology that have boomed during the past two decades. Many improvements are based on the controlled manufacturing of nanostructures that enable tailored material functionalization for a wide range of industrial applications, electronics, medicine, etc., and have already found entry into our daily life. One appealing approach for manufacturing such nanostructures in a flexible, robust, rapid, and contactless one-step process is based on the generation of laser-induced periodic surface structures (LIPSS). This Perspectives article analyzes the footprint of the research area of LIPSS on the basis of a detailed literature search, provides a brief overview on its current trends, describes the European funding strategies within the Horizon 2020 programme, and outlines promising future directions.
KW - Laser-induced periodic surface structures (LIPSS)
KW - Direct laser interference patterning (DLIP)
KW - Surface functionalization
KW - Literature survey
KW - European funding strategies
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-513530
DO - https://doi.org/10.3390/nano10101950
SN - 2079-4991
VL - 10
IS - 10
SP - 1950-1
EP - 1950-19
PB - MDPI
CY - Basel
AN - OPUS4-51353
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bonse, Jörn
A1 - Gräf, S.
T1 - Maxwell Meets Marangoni — A Review of Theories on Laser‐Induced Periodic Surface Structures
N2 - Surface nanostructuring enables the manipulation of many essential surface properties. With the recent rapid advancements in laser technology, a contactless large‐area processing at rates of up to m2 s−1 becomes feasible that allows new industrial applications in medicine, optics, tribology, biology, etc. On the other hand, the last two decades enable extremely successful and intense research in the field of so‐called laser‐induced periodic surface structures (LIPSS, ripples). Different types of these structures featuring periods of hundreds of nanometers only—far beyond the optical diffraction limit—up to several micrometers are easily manufactured in a single‐step process and can be widely controlled by a proper choice of the laser processing conditions. From a theoretical point of view, however, a vivid and very controversial debate emerges, whether LIPSS originate from electromagnetic effects or are caused by matter reorganization. This article aims to close a gap in the available literature on LIPSS by reviewing the currently existent theories of LIPSS along with their numerical implementations and by providing a comparison and critical assessment of these approaches.
KW - Laser-induced periodic surface structures (LIPSS)
KW - Electromagnetic theories
KW - Matter reorganization theories
KW - Surface plasmon polaritons
KW - Self-organization
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514089
DO - https://doi.org/10.1002/lpor.202000215
SN - 1863-8899
VL - 14
IS - 10
SP - 2000215-1
EP - 2000215-25
PB - Wiley
CY - Berlin
AN - OPUS4-51408
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bonse, Jörn
A1 - Gräf, S.
T1 - Ten Open Questions about Laser-Induced Periodic Surface Structures
N2 - Laser-induced periodic surface structures (LIPSS) are a simple and robust route for the nanostructuring of solids that can create various surface functionalities featuring applications in optics, medicine, tribology, energy technologies, etc. While the current laser technologies already allow surface processing rates at the level of m2/min, industrial applications of LIPSS are sometimes hampered by the complex interplay between the nanoscale surface topography and the specific surface chemistry, as well as by limitations in controlling the processing of LIPSS and in the long-term stability of the created surface functions. This Perspective article aims to identify some open questions about LIPSS, discusses the pending technological limitations, and sketches the current state of theoretical modelling. Hereby, we intend to stimulate further research and developments in the field of LIPSS for overcoming these limitations and for supporting the transfer of the LIPSS technology into industry.
KW - Laser-induced periodic surface structures (LIPSS)
KW - Industrial application
KW - Functional properties
KW - Surface functionalization
KW - Modelling
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539503
DO - https://doi.org/10.3390/nano11123326
SN - 2079-4991
VL - 11
IS - 12
SP - 1
EP - 21
PB - MDPI
CY - Basel, Switzerland
AN - OPUS4-53950
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bonse, Jörn
A1 - Krüger, Jörg
T1 - Structuring of thin films by ultrashort laser pulses
N2 - Modern life and global communication would not be possible without technologically tailored thin films; they are omnipresent in daily life applications. In most cases, the films are deposited entirely at the carrying substrates in a specific processing step of the device or sample. In some cases, however, removal or modification must be performed locally, i.e., site-controlled and material selective through an additional laser processing step. For that ultrashort laser pulses with durations in the femtosecond and picosecond range can provide unique advantages and capabilities in industrially scalable schemes. This article reviews the current state of the research and corresponding industrial transfer related to the structuring of thin films by ultrashort pulsed lasers. It focuses on the pertinent historic developments, reveals the relevant physical and chemical effects, explores the ultimate limits, and discusses selected industrial and scientific applications.
KW - Thin films
KW - Laser processing
KW - Ultrashort lasers
KW - Laser damage
KW - Femtosecond laser ablation
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565732
DO - https://doi.org/10.1007/s00339-022-06229-x
SN - 0947-8396
SN - 1432-0630
VL - 129
IS - 1
SP - 1
EP - 38
PB - Springer
CY - Berlin
AN - OPUS4-56573
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 - Bonse, Jörn
A1 - Spaltmann, Dirk
T1 - Editorial: Special issue "Laser-induced periodic surface nano- and microstructures for tribological applications"
N2 - Laser material processing is an emerging technology that generates surface functionalities on the basis of optical, mechanical, or chemical properties. In the form of laser surface texturing (LST), it has attracted a remarkable amount of research to tailor surface properties towards various tribological applications. The main advantages of this single-step, laser-based technology are the contactless machining, featuring a high flexibility, efficiency, and speed, along with the excellent quality of the processed products. LST can be applied precisely localized to sub-micrometric areas, but, via laser beam scanning, it is also feasible for structuring large surface areas at the square meter size.
This Special Issue focuses on the latest developments concerning the tribological performance of laser-generated periodic surface nano- and microstructures and their applications. This includes the laser-based processing of different surface patterns, such as “self-organized” laser-induced periodic surface structures (LIPSS, ripples), grooves, micro-spikes, hierarchical hybrid nano-/micro-structures, microfeatures generated by direct laser interference patterning (DLIP), or even dimples or other topographic geometries shaped by direct laser modification or ablation. The applications of these periodically nano- and micro-patterned surfaces may improve the lubricated or non-lubricated tribological performance of surfaces in conformal and even non-conformal contact through a reduction of wear, a variation of the coefficient of friction, altered load carrying capacity, etc., resulting in energy saving, improved reliability, increased lifetimes as well as durability, leading in turn to extended maintenance intervals/reduced down-time. This can be beneficial in terms of bearings, gears, engines, seals, cutting tools, or other tribological components. Fundamental aspects addressed may involve the investigation of the relevant physical and chemical effects accompanying the laser-generated nano- and microscale topographies, such as alterations of the material structures, the hardness, superficial oxidation, the role of additives contained in lubricants, surface wettability, micro-hydrodynamic effects, etc.
For this Special Issue we aim to attract both academic and industrial researchers and would like to provide a bridge between research in the fields of tribology and laser material processing in order to foster the current knowledge and present new ideas for future applications and new technologies.
KW - Laser-induced periodic surface structures (LIPSS)
KW - Tribology
KW - Applications
KW - Wear
KW - Friction
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-505948
DO - https://doi.org/10.3390/lubricants8030034
SN - 2075-4442
VL - 8
IS - 3
SP - 34, 1
EP - 34, 3
PB - MDPI
CY - Basel
AN - OPUS4-50594
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bornemann-Pfeiffer, Martin
A1 - Wolf, Jakob
A1 - Meyer, Klas
A1 - Kern, S.
A1 - Angelone, D.
A1 - Leonov, A.
A1 - Cronin, L.
A1 - Emmerling, Franziska
T1 - Standardization and control of Grignard reactions in a universal chemical synthesis machine using online NMR
T1 - Standardisierung und Kontrolle von Grignard-Reaktionen mittels Online-NMR in einer universellen chemischen Syntheseplattform
N2 - A big problem with the chemistry literature is that it is not standardized with respect to precise operational parameters, and real time corrections are hard to make without expert knowledge. This lack of context means difficult reproducibility because many steps are ambiguous, and hence depend on tacit knowledge. Here we present the integration of online NMR into an automated chemical synthesis machine (CSM aka. “Chemputer” which is capable of small-molecule synthesis using a universal programming language) to allow automated analysis and adjustment of reactions on the fly. The system was validated and benchmarked by using Grignard reactions which were chosen due to their importance in synthesis. The system was monitored in real time using online-NMR, and spectra were measured continuously during the reactions. This shows that the synthesis being done in the Chemputer can be dynamically controlled in response to feedback optimizing the reaction conditions according to the user requirements.
N2 - Ein Problem der chemischen Literatur ist die fehlende Standardisierung bezüglich genauer Bedingungen, auch Echtzeit-Korrekturen sind ohne Expertenwissen nur schwer möglich. Dieser Mangel an Details erschwert experimentelle Reproduzierbarkeit, da Schritte oft mehrdeutig sind und daher von implizitem Wissen abhängen. Hier präsentieren wir die Integration von Online-NMR Spektroskopie in eine automatisierte chemische Syntheseplattform (CSM aka. “Chemputer”, unter Verwendung einer universellen Programmiersprache zur Synthese kleiner Moleküle fähig), um eine automatisierte Analyse und Anpassung von Reaktionen im laufenden Betrieb zu ermöglichen. Das System wurde anhand von Grignard-Reaktionen, die aufgrund ihrer Bedeutung für die Synthese ausgewählt wurden, validiert und einem Härtetest unterzogen. Synthesen wurden in Echtzeit mit Online-NMR überwacht, und die Spektren wurden während der Reaktionen kontinuierlich aufgenommen und analysiert. Dies zeigt, dass der Chemputer dynamisch mittels einer Regelung kontrolliert werden kann, um die Reaktionsbedingungen entsprechend den Anforderungen des Benutzers zu optimieren.
KW - Grignard reaction
KW - NMR spectroscopy
KW - Process analytical technology
KW - Process control
KW - Grignard-Reaktion
KW - NMR-Spektroskopie
KW - Prozessanalytik
KW - Prozesskontrolle
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531260
DO - https://doi.org/10.1002/anie.202106323
SN - 1521-3773
SN - 1433-7851
N1 - Bibliografische Angaben für die deutsche Version: Angewandte Chemie 2021, Jg. 133, S. 1–7, ISSN 0044-8249, ISSN 1521-3757, https://doi.org/10.1002/ange.202106323 - Bibliographic information for the German version: Angewandte Chemie 2021, vol. 133, p. 1–7, ISSN 0044-8249, ISSN 1521-3757, https://doi.org/10.1002/ange.202106323
VL - 60
IS - 43
SP - 1
EP - 6
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-53126
LA - mul
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Borzekowski, Antje
A1 - Drewitz, T.
A1 - Keller, Julia
A1 - Pfeifer, Dietmar
A1 - Kunte, Hans-Jörg
A1 - Koch, Matthias
A1 - Rohn, S.
A1 - Maul, R.
T1 - Biosynthesis and characterization of zearalenone-14-sulfate, zearalenone-14-glucoside and zearalenone-16-glucoside using common fungal strains
N2 - Zearalenone (ZEN) and its phase II sulfate and glucoside metabolites have been detected in food and feed commodities. After consumption, the conjugates can be hydrolyzed by the human intestinal microbiota leading to liberation of ZEN that implies an underestimation of the true ZEN exposure. To include ZEN conjugates in routine analysis, reliable standards are needed, which are currently not available. Thus, the aim of the present study was to develop a facilitated biosynthesis of ZEN-14-sulfate, ZEN-14-glucoside and ZEN-16-glucoside. A metabolite screening was conducted by adding ZEN to liquid fungi cultures of known ZEN conjugating Aspergillus and Rhizopus strains. Cultivation conditions and ZEN incubation time were varied. All media samples were analyzed for metabolite formation by HPLC-MS/MS. In addition, a consecutive biosynthesis was developed by using Fusarium graminearum for ZEN biosynthesis with subsequent conjugation of the toxin by utilizing Aspergillus and Rhizopus species. ZEN-14-sulfate (yield: 49%) is exclusively formed by Aspergillus oryzae. ZEN-14-glucoside (yield: 67%) and ZEN-16-glucoside (yield: 39%) are formed by Rhizopus oryzae and Rhizopus oligosporus, respectively. Purities of ≥73% ZEN-14-sulfate, ≥82% ZEN-14-glucoside and ≥50% ZEN-16-glucoside were obtained by 1H-NMR. In total, under optimized cultivation conditions, fungi can be easily utilized for a targeted and regioselective synthesis of ZEN conjugates.
KW - Mycotoxin
KW - Zearalenone
KW - Conjugate
KW - Biosynthesis
KW - Fusarium
KW - Aspergillus
KW - Rhizopus
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-444246
DO - https://doi.org/10.3390/toxins10030104
SN - 2072-6651
VL - 10
IS - 3
SP - Article 104, 1
EP - 15
PB - MDPI
CY - Basel
AN - OPUS4-44424
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Brandl, F.
A1 - Thünemann, Andreas
A1 - Beuermann, S.
T1 - Poly(meth)acrylate-PVDF core–shell particles from emulsion polymerization: preferential formation of the PVDF β crystal phase
N2 - A facile and convenient approach for the synthesis of core–shell particles via emulsion polymerization is presented. The shell consists of poly(vinylidene fluoride) (PVDF) and the core of poly(methyl methacrylate) (PMMA), poly(glycidyl methacrylate) (PGMA) or poly(methyl acrylate) (PMA). In a first step, a non-fluorinated (meth)acrylate monomer is polymerized in the emulsion to produce poly(meth)acrylate core particles. Secondly, vinylidene fluoride (VDF) is directly added to the reactor and polymerized for shell formation. Small-angle X-ray scattering (SAXS) was employed to characterize the structure of the core–shell particles. Interestingly, the particles’ core contains fluorinated and non-fluorinated polymers, whereas the shell of the particles consists only of PVDF. The resulting particles with a diameter of around 40 nm show a significantly higher PVDF β phase content than the PVDF homopolymer obtained by emulsion polymerization
KW - Small-angle x-ray scattering
KW - SAXS
KW - Nanopatricle
KW - Polymer
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-465910
DO - https://doi.org/10.1039/C8PY01236A
SN - 1759-9954
SN - 1759-9962
VL - 9
IS - 44
SP - 5359
EP - 5369
PB - The Royal Society of Chemistry
AN - OPUS4-46591
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Breitenbach, Romy
A1 - Gerrits, Ruben
A1 - Dementyeva, Polina
A1 - Knabe, Nicole
A1 - Schumacher, Julia
A1 - Feldmann, Ines
A1 - Radnik, Jörg
A1 - Ryo, M.
A1 - Gorbushina, Anna
T1 - The role of extracellular polymeric substances of fungal biofilms in mineral attachment and weathering
N2 - The roles extracellular polymeric substances (EPS) play in mineral attachment and weathering were studied using genetically modified biofilms of the rock-inhabiting fungus Knufia petricola strain A95. Mutants deficient in melanin and/or carotenoid synthesis were grown as air-exposed biofilms. Extracted EPS were quantified and characterised using a combination of analytical techniques. The absence of melanin affected the quantity and composition of the produced EPS: mutants no longer able to form melanin synthesised more EPS containing fewer pullulan-related glycosidic linkages. Moreover, the melanin-producing strains attached more strongly to the mineral olivine and dissolved it at a higher rate. We hypothesise that the pullulan-related linkages, with their known adhesion functionality, enable fungal attachment and weathering. The released phenolic intermediates of melanin synthesis in the Δsdh1 mutant might play a role similar to Fe-chelating siderophores, driving olivine dissolution even further. These data demonstrate the need for careful compositional and quantitative analyses of biofilm-created microenvironments.
KW - Biofilms
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-549025
DO - https://doi.org/10.1038/s41529-022-00253-1
SN - 2397-2106
VL - 6
SP - 1
EP - 11
PB - Springer Nature
CY - London
AN - OPUS4-54902
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bresch, Harald
A1 - Hodoroaba, Vasile-Dan
A1 - Schmidt, Alexandra
A1 - Rasmussen, K.
A1 - Rauscher, H.
T1 - Counting Small Particles in Electron Microscopy Images — Proposal for Rules and Their Application in Practice
N2 - Electron microscopy (EM) is the gold standard for the characterisation of the morphology (size and shape) of nanoparticles. Visual observation of objects under examination is always a necessary first step in the characterisation process. Several questions arise when undertaking to identify and count particles to measure their size and shape distribution. In addition to challenges with the dispersion and identification of the particles, more than one protocol for counting particles is in use. This paper focuses on precise rules for the counting of particles in EM micrographs, as this influences the measurement accuracy of the number of particles, thus implicitly affecting the size values of the counted particles. We review and compare four different, commonly used methods for counting, which we then apply in case studies. The impact of the selected counting rule on the obtained final particle size distribution is highlighted. One main aim of this analysis is to support the application of a specific, well-defined counting approach in accordance with regulatory
requirements to contribute to achieving more reliable and reproducible results. It is also useful for the new harmonised measurement procedures for determining the particle size and particle size distribution of nanomaterials.
KW - Nano
KW - Particle size distribution
KW - Nanoparticle
KW - Nanomaterial
KW - OECD
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551891
DO - https://doi.org/10.3390/nano12132238
SN - 2079-4991
VL - 12
IS - 13
SP - 2238
PB - MDPI
CY - Basel
AN - OPUS4-55189
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Brockmann, N.
A1 - Sicken, A.
A1 - Krüger, Jörg
T1 - Effects of laser cleaning on the condition of different silk model samples using varying wavelengths and pulse durations
N2 - The cleaning of aged silk fibers poses a common challenge in the conservation of textiles, since traditional cleaning techniques often yield unsatisfactory results or even harm objects. In this regard, cleaning objects with laser radiation is a promising addition to the range of available methods. Due to it being contactless, even brittle and touch-sensitive objects with disfiguring or harmful soiling could potentially be cleaned and therefore made accessible for research and presentation. Examples of treatment have sometimes shown spectacular results. Still there is some skepticism concerning the safety of this treatment for textile materials, which has been strengthened through previous 532 nm wavelength nanosecond laser cleaning studies on silk fibers. Taking these published results into account, the range of examined laser parameters has been extended in this study, from 532 nm nanosecond laser to 1064 nm nanosecond and even 800 nm femtosecond laser, reevaluating the effect of this treatment on the fibers. The physicochemical processes taking place on the silk fibers when cleaning with lasers are complex and still not fully understood. The aim of this project was therefore to bring more clarification about potential effects of those processes on the condition of silk samples treated with a set of different parameters for wavelength, pulse duration, energy density and number of pulses per spot. It also looks at the influence of the presence of soiling on the results. The analysis of potential effects was then carried out using statistical methods and advanced analytics. Scanning electron microscopy, Fourier-transform infrared spectroscopy and colorimetry technology provided the required insights to better assess the effects. Results show that laser cleaning of silk fibers, like most other conventional cleaning techniques, is not completely without risk, but knowing what the possible effects are helps making decisions on whether the benefits of the technique used justify these risks.
KW - Laser cleaning
KW - Cultural heritage
KW - Conservation
KW - Silk
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594601
DO - https://doi.org/10.1186/s40494-024-01152-1
SN - 2050-7445
VL - 12
IS - 1
SP - 1
EP - 15
PB - Springer
AN - OPUS4-59460
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Broicher, Cornelia
A1 - Zeng, F.
A1 - Pfänder, N.
A1 - Frisch, M.
A1 - Bisswanger, T.
A1 - Radnik, Jörg
A1 - Stockmann, Jörg M.
A1 - Palkovits, S.
A1 - Beine, A. K.
A1 - Palkovits, R.
T1 - Iron and Manganese Containing Multi-Walled Carbon Nanotubes as Electrocatalysts for the Oxygen Evolution Reaction - Unravelling Influences on Activity and Stability
N2 - Hydrogen economy is a central aspect of future energy supply, as hydrogen can be used as energy storage and fuel. In order tomake water electrolysis efficient, the limiting oxygen evolution reaction (OER) needs to be optimized. Therefore, C-based composite materials containing earth-abundant Fe and Mn were synthesized, characterized and tested in the OER. For pyrolysis temperatures above 700°C N-rich multi-walled carbon nanotubes (MWCNT) are obtained. Inside the tubes Fe3C particles are formed, Fe and Mn oxides are incorporated in the carbon matrix and metal spinel nanoparticles cover the outer surface. The best catalyst prepared at 800°C achieves a low overpotential of 389 mV (at 10 mA/cm2) and high stability (22.6 h). From electrochemical measurements and characterization it can be concluded that the high activity is mainly provided by MWCNT, Fe3C and the metal oxides in the conductive carbon matrix. The metal spinel nanoparticles in
contrast protect the MWCNT from oxidation and thereby contribute to the high stability.
KW - Oxygen Evolution Reaction
KW - Carbon Nanotubes
KW - Stability
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-513955
DO - https://doi.org/10.1002/cctc.202000944
VL - 12
IS - 21
SP - 1
EP - 8
PB - Wiley Online Libary
AN - OPUS4-51395
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Broichert, C.
A1 - Klingenhof, M.
A1 - Frisch, M.
A1 - Dresp, S.
A1 - Kubo, N.M.
A1 - Artz, J.
A1 - Radnik, Jörg
A1 - Palkovits, S.
A1 - Beine, A.K.
A1 - Strasser, P.
A1 - Palkovits, R.
T1 - Particle size-controlled synthesis of highperformance MnCo-based materials for alkaline OER at fluctuating potentials
N2 - For the large-scale generation of hydrogen via water electrolysis the design of long term stable and active catalysts for the oxygen evolution reaction (OER) remains a key challenge. Most catalysts suffer from severe structural corrosion that becomes even more pronounced at fluctuating potentials. Herein, MnCo based cubic particles were prepared via a hydrothermal approach, in which the edge length of the micron-sized particles can be controlled by changing the pH value of the precursor solution. The cubes are composed of varying amounts of MnCo2O4, CoCO3 and a mixed (Mn/Co)CO3 phase. Structure–activity relationships were deduced revealing a volcano-type behavior for the intrinsic OER activity and fraction of spinel oxide phase.
A low overpotential of 0.37 V at 10 mA cm−2 and a stability of more than 25 h was achieved in 1.0 M KOH using a rotating disc electrode (RDE) setup. The best performing catalyst material was successfully tested under dynamic process conditions for 9.5 h and shows a superior catalytic activity as anode for the Overall water splitting in an electrolyser setup in 1.0 M KOH at 333 K compared to a reference NiCo-spinel catalyst.
KW - Water electrolysis
KW - Oxygen evolution reaction
KW - Structure activity relationships
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-536050
DO - https://doi.org/10.1039/d1cy00905b
SN - 2044-4753
VL - 11
IS - 12
SP - 7278
EP - 7286
PB - Royal Society of Chemistry
AN - OPUS4-53605
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Brzeska, J.
A1 - Elert, Anna Maria
A1 - Morawska, M.
A1 - Sikorska, W.
A1 - Kowalczuk, M.
A1 - Rutkowska, M.
T1 - Branched Polyurethanes Based on Synthetic Polyhydroxybutyrate with Tunable Structure and Properties
N2 - Branched, aliphatic polyurethanes (PURs) were synthesized and compared to linear analogues. The influence of polycaprolactonetriol and synthetic poly([R,S]-3-hydroxybutyrate) (R,S-PHB) in soft segments on structure, thermal and sorptive properties of PURs was determined.
Using FTIR and Raman spectroscopies it was found that increasing the R,S-PHB amount in the structure of branched PURs reduced a tendency of urethane groups to hydrogen bonding. Melting enthalpies (on DSC thermograms) of both soft and hard segments of linear PURs were higher than branched PURs, suggesting that linear PURs were more crystalline. Oil sorption by samples of linear and branched PURs, containing only polycaprolactone chains in soft segments, was higher than in the case of samples with R,S-PHB in their structure. Branched PUR without R,S-PHB absorbed the highest amount of oil. Introducing R,S-PHB into the PUR structure increased water sorption.
Thus, by operating the number of branching and the amount of poly([R,S]-3-hydroxybutyrate) in soft segments thermal and sorptive properties of aliphatic PURs could be controlled.
KW - IR
KW - Polyurethane
KW - PUR
KW - RAMAN
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-457087
DO - https://doi.org/10.3390/polym10080826
VL - 10
IS - 8
SP - 826, 1
EP - 12
PB - MDPI
AN - OPUS4-45708
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 - Brüngel, R.
A1 - Rückert, J.
A1 - Wohlleben, W.
A1 - Babick, F.
A1 - Ghanem, A.
A1 - Gaillard, C.
A1 - Mech, A.
A1 - Rauscher, H.
A1 - Hodoroaba, Vasile-Dan
A1 - Weigel, S.
A1 - Friedrich, C. M.
T1 - NanoDefiner e-Tool: An Implemented Decision Support Framework for Nanomaterial Identification
N2 - The European Commission’s recommendation on the definition of nanomaterial (2011/696/EU) established an applicable standard for material categorization. However, manufacturers face regulatory challenges during registration of their products. Reliable categorization is difficult and requires considerable expertise in existing measurement techniques (MTs). Additionally, organizational complexity is increased as different authorities’ registration processes require distinct reporting.
The NanoDefine project tackled these obstacles by providing the NanoDefiner e-tool: A decision support expert system for nanomaterial identification in a regulatory context. It providesMT recommendations for categorization of specific materials using a tiered approach (screening/confirmatory), and was constructed with experts from academia and industry to be extensible, interoperable, and adaptable for forthcoming revisions of the nanomaterial definition. An implemented MT-driven material categorization scheme allows detailed description. Its guided workflow is suitable for a variety of user groups. Direct feedback and explanation enable transparent decisions. Expert knowledge is Held in a knowledge base for representation of MT performance criteria and physicochemical particle type
properties. Continuous revision ensured data quality and validity. Recommendations were validated by independent case studies on industry-relevant particulate materials. Besides supporting material identification and registration, the free and open-source e-tool may serve as template for other expert systems within the nanoscience domain.
KW - EC nanomaterial definition
KW - Decision support
KW - Expert system
KW - Nanomaterial
KW - Nanoparticles
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-492449
DO - https://doi.org/10.3390/ma12193247
VL - 12
IS - 19
SP - 3247
PB - MDPI
CY - Basel, CH
AN - OPUS4-49244
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bugel, S.
A1 - Hahnel, M.
A1 - Kunde, T.
A1 - de Sousa Amadeu, Nadar
A1 - Sun, Y.
A1 - Spieß, A.
A1 - Beglau, T. H. Y.
A1 - Janiak, C.
A1 - Schmidt, B. M.
T1 - Synthesis and Characterization of a Crystalline Imine-Based Covalent Organic Framework with Triazine Node and Biphenyl Linker and Its Fluorinated Derivate for CO2/CH4 Separation
N2 - A catalyst-free Schiff base reaction was applied to synthesize two imine-linked covalent organic frameworks (COFs). The condensation reaction of 1,3,5-tris-(4-aminophenyl)triazine (TAPT) with 4,4′-biphenyldicarboxaldehyde led to the structure of HHU-COF-1 (HHU = Heinrich-Heine University). The fluorinated analog HHU-COF-2 was obtained with 2,2′,3,3′,5,5′,6,6′-octafluoro-4,4′-biphenyldicarboxaldehyde. Solid-state NMR, infrared spectroscopy, X-ray photoelectron spectroscopy, and elemental analysis confirmed the successful formation of the two network structures. The crystalline materials are characterized by high Brunauer–Emmett–Teller surface areas of 2352 m2/g for HHU-COF-1 and 1356 m2/g for HHU-COF-2. The products of a larger-scale synthesis were applied to prepare mixed-matrix membranes (MMMs) with the polymer Matrimid. CO2/CH4 permeation tests revealed a moderate increase in CO2 permeability at constant selectivity for HHU-COF-1 as a dispersed phase, whereas application of the fluorinated COF led to a CO2/CH4 selectivity increase from 42 for the pure Matrimid membrane to 51 for 8 wt% of HHU-COF-2 and a permeability increase from 6.8 to 13.0 Barrer for the 24 wt% MMM.
KW - MOF
KW - Filter
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547632
DO - https://doi.org/10.3390/ma15082807
SN - 1996-1944
VL - 15
IS - 8
SP - 1
EP - 18
PB - MDPI
AN - OPUS4-54763
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bui, M.
A1 - Hoffmann, K. F.
A1 - Braun, T.
A1 - Riedel, S.
A1 - Heinekamp, Christian
A1 - Scheurell, K.
A1 - Scholz, G.
A1 - Stawski, Tomasz
A1 - Emmerling, Franziska
T1 - An Amorphous Teflate Doped Aluminium Chlorofluoride:
A Solid Lewis-Superacid for the Dehydrofluorination of
Fluoroalkanes
N2 - Ananion-dopedaluminiumchlorofluoride AlCl0.1F2.8(OTeF5)0.1(ACF-teflate) was synthesized.The material contains pentafluor-oorthotellurate(teflate)groups, which mimic fluoride ions electronically, but are sterically more demanding. They are embedded into the amorphous structure. The latter was studied by PDF analysis, EXAFS data and MAS NMR spectroscopy. The mesoporous powder is a Lewis superacid, and ATR-IR spectra of adsorbed CD3CN reveal a blue-shift of the adsorption band by73 cm-1, which is larger than the shift for SbF5. Remarkably,ACF-teflate catalyzes dehydrofluorination reactions of mono-fluoroalkanes to yield olefins in C6D6. In these cases,no Friedel-Crafts products were formed.
KW - Aluminium fluorides
KW - Aluminium teflates
KW - C-F bond activation
KW - Lewis superacids
KW - Silanes
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572290
DO - https://doi.org/10.1002/cctc.202300350
SN - 1867-3880
SP - 1
EP - 7
PB - Wiley VHC-Verlag
AN - OPUS4-57229
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Burek, K.
A1 - Dengler, J.
A1 - Emmerling, Franziska
A1 - Feldmann, Ines
A1 - Kumke, M. U.
A1 - Stroh, Julia
T1 - Lanthanide Luminescence Revealing the Phase Composition in Hydrating Cementitious Systems
N2 - The hydration process of Portland cement in a cementitious system is crucial for development of the high-quality cementbased construction material. Complementary experiments of Xray diffraction analysis (XRD), scanning electron microscopy (SEM) and time-resolved laser fluorescence spectroscopy (TRLFS) using europium (Eu(III)) as an optical probe are used to analyse the hydration process of two cement systems in the absence and presence of different organic admixtures.
We Show that different analysed admixtures and the used sulphate carriers in each cement system have a significant influence on the hydration process, namely on the time-dependence in the formation of different hydrate phases of cement. Moreover, the effect of a particular admixture is related to the type of sulphate carrier used.
The quantitative information on the amounts of the crystalline cement paste components is accessible via XRD analysis. Distinctly different morphologies of ettringite and calcium-silicate-hydrates (C-S-H) determined by SEM allow visual conclusions about formation of these phases at particular ageing times. The TRLFS data provides information about the admixture influence on the course of the silicate reaction. The dip in the dependence of the luminescence decay times on the hydration time indicates the change in the structure of C-S-H in the early hydration period. Complementary information from XRD, SEM and TRLFS provides detailed information on distinct periods of the cement hydration process.
KW - Cement admixtures
KW - Cement hydration
KW - Europium
KW - Luminescence
KW - SEM
KW - X-ray diffraction
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504842
DO - https://doi.org/10.1002/open.201900249
VL - 8
IS - 12
SP - 1441
EP - 1452
PB - Wiley-VCH
AN - OPUS4-50484
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Böttcher, Katrin
A1 - Schmitt Rahner, M.
A1 - Stolzenberg, U.
A1 - Kraft, Sebastian
A1 - Bonse, Jörn
A1 - Feist, C.
A1 - Albrecht, D.
A1 - Pullner, B.
A1 - Krüger, Jörg
T1 - Worst-case X-ray photon energies in ultrashort pulse laser processing
N2 - Ultrashort pulse laser processing can result in the secondary generation of unwanted X-rays if a critical laser irradiance of about 10^13 W/cm^2 is exceeded. Spectral X-ray emissions were investigated during the processing of tungsten and steel using three complementary spectrometers (based on CdTe and silicon drift detectors) simultaneously for the identification of a worst-case spectral scenario. Therefore, maximum X-ray photon energies were determined, and corresponding dose equivalent rates were calculated. An ultrashort pulse laser workstation with a pulse duration of 274 fs, a center wavelength of 1030 nm, pulse repetition rates between 50 kHz and 200 kHz, and a Gaussian laser beam focused to a spot diameter of 33 µm was employed in a single pulse and burst laser operation mode. Different combinations of laser pulse energy and repetition rate were utilized, keeping the average laser power constant close to the maximum power of 20 W. Peak irradiances ranging from 7.3 × 10^13 W/cm^2 up to 3.0 × 10^14 W/cm^2 were used. The X-ray dose equivalent rate increases for lower repetition rates and higher pulse energy if a constant average power is used. Laser processing with burst mode significantly increases the dose rates and the X-ray photon energies. A maximum X-ray photon energy of about 40 keV was observed for burst mode processing of tungsten with a repetition rate of 50 kHz and a peak irradiance of 3 × 10^14 W/cm^2.
KW - Ultrashort pulsed laser
KW - X-ray emission
KW - X-ray spectrum
KW - X-ray energies
KW - Radiation protection
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-566176
DO - https://doi.org/10.3390/ma15248996
VL - 15
IS - 24
SP - 1
EP - 17
PB - MDPI
AN - OPUS4-56617
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - C. Pardo Pérez, L.
A1 - Arndt, A.
A1 - Stojkovikj, S.
A1 - Y. Ahmet, I.
A1 - T. Arens,, J.
A1 - Dattila, F.
A1 - Wendt, R.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Radtke, Martin
A1 - Davies, V.
A1 - Höflich, K.
A1 - Köhnen, E.
A1 - Tockhorn, P.
A1 - Golnak, R.
A1 - Xiao, J.
A1 - Schuck, G.
A1 - Wollgarten, M.
A1 - López, N.
A1 - T. Mayer, M.
T1 - Determining Structure-Activity Relationships in Oxide Derived CuSn Catalysts During CO2 Electroreduction Using X-Ray Spectroscopy
N2 - The development of earth-abundant catalysts for selective electrochemical CO2 conversion is a central challenge. Cu-Sn bimetallic catalysts can yield selective CO2 reduction toward either CO or formate. This study presents oxide-derived Cu-Sn catalysts tunable for either product and seeks to understand the synergetic effects between Cu and Sn causing these selectivity trends. The materials undergo significant transformations under CO2 reduction conditions, and their dynamic bulk and surface structures are revealed by correlating observations from multiple methods—X-ray absorption spectroscopy for in situ study, and quasi in situ X-ray photoelectron spectroscopy for surface sensitivity. For both types of catalysts, Cu transforms to metallic Cu0 under reaction conditions. However, the Sn speciation and content differ significantly between the catalyst types: the CO-selective catalysts exhibit a surface Sn content of 13 at. % predominantly present as oxidized Sn, while the formate-selective catalysts display an Sn content of ≈70 at. % consisting of both metallic Sn0 and Sn oxide species. Density functional theory simulations suggest that Snδ+ sites weaken CO adsorption, thereby enhancing CO selectivity, while Sn0 sites hinder H adsorption and promote formate production. This study reveals the complex dependence of catalyst structure, composition, and speciation with electrochemical bias in bimetallic Cu catalysts.
KW - Electrochemical CO2 conversion
KW - Cu catalysts
KW - X-ray absorption spectroscopy
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547116
DO - https://doi.org/10.1002/aenm.202103328
SN - 1614-6832
VL - 12
IS - 5
SP - 2103328
PB - Wiley-VCH GmbH
AN - OPUS4-54711
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cakir, Cafer Tufan
A1 - Bogoclu, Can
A1 - Emmerling, Franziska
A1 - Streli, Christina
A1 - Guilherme Buzanich, Ana
A1 - Radtke, Martin
T1 - Machine learning for efficient grazing-exit x-ray absorption near edge structure spectroscopy analysis: Bayesian optimization approach
N2 - In materials science, traditional techniques for analyzing layered structures are essential for obtaining information about local structure, electronic properties and chemical states. While valuable, these methods often require high vacuum environments and have limited depth profiling capabilities. The grazing exit x-ray absorption near-edge structure (GE-XANES) technique addresses these limitations by providing depth-resolved insight at ambient conditions, facilitating in situ material analysis without special sample preparation. However, GE-XANES is limited by long data acquisition times, which hinders its practicality for various applications. To overcome this, we have incorporated Bayesian optimization (BO) into the GE-XANES data acquisition process. This innovative approach potentially reduces measurement time by a factor of 50. We have used a standard GE-XANES experiment, which serve as reference, to validate the effectiveness and accuracy of the BO-informed experimental setup. Our results show that this optimized approach maintains data quality while significantly improving efficiency, making GE-XANES more accessible to a wider range of materials science applications.
KW - Machine Learning
KW - GE-XANES
KW - Bayesian Optimization
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-603955
DO - https://doi.org/10.1088/2632-2153/ad4253
VL - 5
IS - 2
SP - 1
EP - 12
PB - IOP Publishing
AN - OPUS4-60395
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cano Murillo, Natalia
A1 - Ghasem Zadeh Khorasani, Media
A1 - Silbernagl, Dorothee
A1 - Emamverdi, Farnaz
A1 - Cacua, K.
A1 - Hodoroaba, Vasile-Dan
A1 - Sturm, Heinz
T1 - Carrier Fibers for the Safe Dosage of Nanoparticles in Nanocomposites: Nanomechanical and Thermomechanical Study on Polycarbonate/Boehmite Electrospun Fibers Embedded in Epoxy Resin
N2 - The reinforcing effect of boehmite nanoparticles (BNP) in epoxy resins for fiber composite lightweight construction is related to the formation of a soft but bound interphase between filler and polymer. The interphase is able to dissipate crack propagation energy and consequently increases the fracture toughness of the epoxy resin. Usually, the nanoparticles are dispersed in the resin and then mixed with the hardener to form an applicable mixture to impregnate the fibers. If one wishes to locally increase the fracture toughness at particularly stressed positions of the fiber-reinforced polymer composites (FRPC), this could be done by spraying nanoparticles from a suspension. However, this would entail high costs for removing the nanoparticles from the ambient air. We propose that a fiber fleece containing bound nanoparticles be inserted at exposed locations. For the present proof-of-concept study, an electrospun polycarbonate nonwoven and taurine modified BNP are proposed. After fabrication of suitable PC/EP/BNP composites, the thermomechanical properties were tested by dynamic mechanical analysis (DMA). Comparatively, the local nanomechanical properties such as stiffness and elastic modulus were determined by atomic force microscopy (AFM). An additional investigation of the distribution of the nanoparticles in the epoxy matrix, which is a prerequisite for an effective nanocomposite, is carried out by scanning electron microscopy in transmission mode (TSEM). From the results it can be concluded that the concept of carrier fibers for nanoparticles is viable.
KW - Advanced materials
KW - Electrospun nanocomposite fiber
KW - Nanomechanical charecteisation
KW - Nanosafety
KW - Epoxy nanocomposites
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-528265
DO - https://doi.org/10.3390/nano11061591
VL - 11
IS - 6
SP - 1591
PB - MDPI
CY - CH - 4020 Basel, Switzerland
AN - OPUS4-52826
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cano Murillo, Natalia
A1 - Ghasem Zadeh Khorasani, Media
A1 - Silbernagl, Dorothee
A1 - Hahn, Marc Benjamin
A1 - Hodoroaba, Vasile-Dan
A1 - Sturm, Heinz
T1 - Nanomechanical study of polycarbonate/boehmite nanoparticles/epoxy ternary composite and their interphases
N2 - Thermoplastic modified thermosets are of great interest especially due to their improved fracture toughness. Comparable enhancements have been achieved by adding different nanofillers including inorganic particles such as nanosized boehmite. Here, we present a nanomechanical study of two composite systems, the first comprising a polycarbonate (PC) layer in contact with epoxy resin (EP) and the second consisting of a PC layer containing boehmite nanoparticles (BNP) which is also in contact with an EP layer. The interaction between PC and EP monomer is tested by in situ Fourier transformed infrared (FT-IR) analysis, from which a reaction induced phase separation of the PC phase is inferred. Both systems are explored by atomic force microscopy (AFM) force spectroscopy. AFM force-distance curves (FDC) show no alteration of the mechanical properties of EP at the interface to PC. However, when a PC phase loaded with BNP is put in contact with an epoxy system during curing, a considerable mechanical improvement exceeding the rule of mixture was detected.
The trend of BNP to agglomerate preferentially around EP dominated regions and the stiffening effect of BNP on EP shown by spatial resolved measurements of Young's modulus, suggest the effective presence of BNP within the EP phase.
KW - Composites
KW - Mechanical properties
KW - Nanoparticles
KW - Thermoplastics
KW - Thermosets
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-515965
DO - https://doi.org/10.1002/app.50231
SN - 0021-8995
SN - 1097-4628
VL - 138
IS - 12
SP - 1
EP - 11
PB - Wiley
CY - New York, NY
AN - OPUS4-51596
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Casali, L.
A1 - Broll, V.
A1 - Ciurili, S.
A1 - Braga, D.
A1 - Emmerling, Franziska
A1 - Gepioni, F.
T1 - Facilitating Nitrification Inhibition through Green, Mechanochemical Synthesis of a Novel Nitrapyrin Complex
N2 - Nitrapyrin (NP) is applied to cultivated soils to inhibit the enzymatic activity of ammonia monooxygenase (AMO), but its poor aqueous solubility and high volatility severely limit its application. β-Cyclodextrin (β-CD) is commonly used to form inclusion complexes with hydrophobic molecules, improving water solubility and stability upon complexation. Here we report on the mechanochemical synthesis of the inclusion complex β-CD·NP, characterized via a combination of solid-state techniques, including exsitu and in situ X-ray diffraction, Raman and NMR spectroscopies, transmission electron microscopy, and energy dispersive X-ray spectroscopy. The pure inhibitor NP was also structurally characterized. The β-CD·NP complex presents improved solubility and thermal stability, and still inhibits the enzymatic activity of AMO with high efficacy. All results indicate that the inclusion of NP into β-CD represents a viable route for the preparation of a novel class of inhibitors, with improved properties related to stability, water solubility, and good inhibition activity.
KW - Mechanochemistry
KW - Nitrification
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537154
DO - https://doi.org/10.1021/acs.cgd.1c00681
VL - 21
IS - 10
SP - 5792
EP - 5799
PB - ACS Publications
AN - OPUS4-53715
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Casali, Lucia
A1 - Carta, Maria
A1 - Michalchuk, Adam A. L.
A1 - Delogu, Francesco
A1 - Emmerling, Franziska
T1 - Kinetics of the mechanically induced ibuprofen–nicotinamide co-crystal formation by in situ X-ray diffraction
N2 - Mechanochemistry is drawing attention from the pharmaceutical industry given its potential for sustainable material synthesis and manufacture. Scaling mechanochemical processes to industrial level remains a challenge due to an incomplete understanding of their underlying mechanisms. We here show how time-resolved in situ powder X-ray diffraction data, coupled with analytical kinetic modelling, provides a powerful approach to gain mechanistic insight into mechanochemical reactions. By using the ibuprofen–nicotinamide co-crystal mechanosynthesis as a benchmark system, we investigate the behaviour of the solids involved and identify the factors that promote the reaction. As mechanochemical mechanisms become increasingly clear, it promises to become a breakthrough in the industrial preparation of advanced pharmaceuticals.
KW - Mechanochemistry
KW - Kinetics
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608820
DO - https://doi.org/10.1039/D4CP01457J
SN - 1463-9084
VL - 26
SP - 22041
EP - 22048
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-60882
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chambers, M. S.
A1 - Hunter, R. D.
A1 - Hollamby, M. J.
A1 - Pauw, Brian Richard
A1 - Smith, A. J.
A1 - Snow, T.
A1 - Danks, A. E.
A1 - Schnepp, Z.
T1 - In Situ and Ex Situ X‑ray Diffraction and Small-Angle X‑ray Scattering Investigations of the Sol−Gel Synthesis of Fe3N and Fe3C
N2 - Iron nitride (Fe3N) and iron carbide (Fe3C) nanoparticles can be prepared via sol−gel synthesis. While sol−gel methods are simple, it can be difficult to control the crystalline composition, i.e., to achieve a Rietveld-pure product. In a previous in situ synchrotron study of the sol−gel synthesis of Fe3N/Fe3C, we showed that the reaction proceeds as follows:
Fe3O4 → FeOx → Fe3N → Fe3C. There was considerable overlap between the different phases, but we were unable to ascertain whether this was due to the experimental setup (side-on heating of a quartz capillary which could lead to thermal gradients) or whether individual particle reactions proceed at different rates. In this paper, we use in situ wide- and small-angle X-ray scattering (wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS)) to demonstrate that the overlapping phases are indeed due to variable reaction rates. While the initial oxide nanoparticles have a small range of diameters, the size range expands considerably and very rapidly during the oxide−nitride transition. This has implications for the isolation of Rietveld-pure Fe3N, and in an extensive laboratory study, we were indeed unable to isolate phasepure Fe3N. However, we made the surprising discovery that Rietveld-pure Fe3C nanoparticles can be produced at 500 °C with a sufficient furnace dwell time. This is considerably lower than the previous reports of the sol−gel synthesis of Fe3C nanoparticles.
KW - Small-angle X-ray Scattering
KW - SAXS
KW - Diffraction
KW - XRD
KW - Scattering
KW - Sol-gel
KW - Iron nitride
KW - Nanoparticles
KW - Iron carbide
KW - Catalyst
KW - In-situ
KW - Ex-situ
KW - Synthesis
KW - Synchrotron
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548226
DO - https://doi.org/10.1021/acs.inorgchem.1c03442
VL - 61
IS - 18
SP - 6742
EP - 6749
PB - ACS Publications
CY - Washington
AN - OPUS4-54822
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chapartegui-Arias, Ander
A1 - Raysyan, A.
A1 - Belenguer, A. M.
A1 - Jaeger, Carsten
A1 - Tchipilov, Teodor
A1 - Prinz, Carsten
A1 - Abad Andrade, Carlos Enrique
A1 - Beyer, S.
A1 - Schneider, Rudolf
A1 - Emmerling, Franziska
T1 - Tailored mobility in a zeolite imidazolate framework (ZIF) antibody conjugate
N2 - Zeolitic imidazolate framework (ZIF) hybrid fluorescent nanoparticles and ZIF antibody conjugates have been synthesized, characterized, and employed in lateral-flow immunoassay (LFIA). The bright fluorescence of the conjugates and the possibility to tailor their mobility gives a huge potential for diagnostic assays. An enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase (HRP) as label, proved the integrity, stability, and dispersibility of the antibody conjugates, LC-MS/MS provided evidence that a covalent link was established between these metal-organic frameworks and lysine residues in IgG antibodies.
KW - ZIF
KW - ELISA
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532096
DO - https://doi.org/10.1002/chem.202100803
SN - 0947-6539
SN - 1521-3765
VL - 27
IS - 36
SP - 9414
EP - 9421
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-53209
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chemello, Giovanni
A1 - Knigge, Xenia
A1 - Ciornii, Dmitri
A1 - Reed, B.P.
A1 - Pollard, A.J.
A1 - Clifford, C.A.
A1 - Howe, T.
A1 - Vyas, N.
A1 - Hodoroaba, Vasile-Dan
A1 - Radnik, Jörg
T1 - Influence of the Morphology on the Functionalization of Graphene Nanoplatelets Analyzed by Comparative Photoelectron Spectroscopy with Soft and Hard X-Rays
N2 - Since its isolation, graphene has received growing attention from academia and industry due to its unique properties. However, the “what is my material” barrier hinders further commercialization. X-ray photoelectron spectroscopy (XPS) is considered as a method of choice for the determination of the elemental and chemical composition. In this work the influence of the morphology of graphene particles on the XPS results is studied and investigated as a function of X-ray energy, using conventional XPS with Al K𝜶 radiation and hard X-ray photoemission spectroscopy (HAXPES) using Cr K𝜶 radiation. Thereby, the information depth is varied between 10 and 30 nm. For this purpose, two commercial powders containing graphene nanoplatelets with lateral dimensions of either ≈100 nm or in the micrometer range are compared. These larger ones exist as stack of graphene layers which is inspected with scanning electron microscopy. Both kinds of particles are then functionalized with either oxygen or fluorine. The size of the graphene particles is found to influence the degree of functionalization. Only the combination of XPS and HAXPES allows to detect the functionalization at the outermost surface of the particles or even of the stacks and to provide new insights into the functionalization process.
KW - Functionalized graphene
KW - Hard-energy X-ray photoelectron spectroscopy
KW - X-ray photoelectron spectroscopy
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-578860
DO - https://doi.org/10.1002/admi.202300116
SN - 2196-7350
SP - 1
EP - 8
PB - Wiley VCH
AN - OPUS4-57886
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chen, Z.
A1 - Perez, J. P. H.
A1 - Smales, Glen Jacob
A1 - Blukis, R.
A1 - Pauw, Brian Richard
A1 - Stammeier, J. A.
A1 - Radnik, Jörg
A1 - Smith, A. J.
A1 - Benning, L. G.
T1 - Impact of organic phosphates on the structure and composition of short-range ordered iron nanophases
N2 - Organic phosphates (OP) are important nutrient components for living cells in natural environments, where they readily interact with ubiquitous iron phases such as hydrous ferric oxide, ferrihydrite (FHY). FHY partakes in many key bio(geo)chemical reactions including iron-mediated carbon storage in soils, or iron-storage in living organisms. However, it is still unknown how OP affects the formation, structure and properties of FHY. Here, we document how β-glycerophosphate (GP), a model OP ligand, affects the structure and properties of GP–FHY nanoparticles synthesized by coprecipitation at variable nominal molar P/Fe ratios (0.01 to 0.5). All GP–FHY precipitates were characterized by a maximum solid P/Fe ratio of 0.22, irrespective of the nominal P/Fe ratio. With increasing nominal P/Fe ratio, the specific surface area of the GP–FHY precipitates decreased sharply from 290 to 3 m2 g−1, accompanied by the collapse of their pore structure. The Fe–P local bonding environment gradually transitioned from a bidentate binuclear geometry at low P/Fe ratios to monodentate mononuclear geometry at high P/Fe ratios. This transition was accompanied by a decrease in coordination number of edge-sharing Fe polyhedra, and the loss of the corner-sharing Fe polyhedra. We show that Fe(III) polymerization is impeded by GP, and that the GP–FHY structure is highly dependent on the P/Fe ratio. We discuss the role that natural OP-bearing Fe(III) nanophases have in biogeochemical reactions between Fe–P and C species in aquatic systems.
KW - Organic phosphates
KW - Iron nanophases
KW - Scattering
KW - Diffraction
KW - Nanomaterials
KW - Coprecipitation
KW - Carbon storage
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599399
DO - https://doi.org/10.1039/d3na01045g
SN - 2516-0230
SP - 1
EP - 13
PB - Royal Society of Chemistry (RSC)
CY - Cambridge
AN - OPUS4-59939
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chewle, Surahit
A1 - Emmerling, Franziska
A1 - Weber, M.
T1 - Effect of choice of solvent on crystallization pathway of paracetamol: An experimental and theoretical case study
N2 - The choice of solvents influences crystalline solid formed during the crystallization of active pharmaceutical ingredients (API). The underlying effects are not always well understood because of the complexity of the systems. Theoretical models are often insufficient to describe this phenomenon. In this study, the crystallization behavior of the model drug paracetamol in different solvents was studied based on experimental and molecular dynamics data. The crystallization process was followed in situ using time-resolved Raman spectroscopy. Molecular dynamics with simulated annealing algorithm was used for an atomistic understanding of the underlying processes. The experimental and theoretical data indicate that paracetamol molecules adopt a particular geometry in a given solvent predefining the crystallization of certain polymorphs
KW - Crystallization
KW - Nucleation
KW - Polymorphism
KW - Raman spectroscopy
KW - Cassical nucleation theory
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520052
DO - https://doi.org/10.3390/cryst10121107
SN - 2073-4352
VL - 10
IS - 12
SP - 1
EP - 10
PB - MDPI
CY - Basel
AN - OPUS4-52005
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chinellato, Fabio
A1 - Wilbig, Janka
A1 - Al-Sabbagh, Dominik
A1 - Colombo, P.
A1 - Günster, Jens
T1 - Gas flow assisted powder deposition for enhanced flowability of fine powders: 3D printing of alpha-tricalcium phosphate
N2 - The possibility of creating patient-specific individual implants makes Additive Manufacturing technologies of special interest for the medical sector. For substitution of bone defects, powder based Additive Manufacturing by Binder Jetting is a suitable method to produce complex scaffold-like structures made of bioceramics with easily adapted geometries and controlled porosity. The process inherent residual porosity in the printed part, even though desired as it supports bone ingrowth, also leads to limited mechanical strength. Currently, bioceramic scaffolds made by Binder Jetting feature suitable biocompatible and biodegradable properties, while a sufficient mechanical stability is rather challenging. The purpose of this work is to apply the gas flow assisted powder deposition introduced in 2014 by Zocca et al., to the powder bed during printing of bioceramic tablets and scaffolds using α-TCP powder as feedstock. This enables exploiting the advantages of an increased powder bed density, thereby improving the mechanical properties of the printed parts.
KW - Additive Manufacturing
KW - Binder Jetting
KW - Gas flow assisted powder deposition
KW - Alpha-tricalcium phosphate
KW - Scaffold
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510138
DO - https://doi.org/10.1016/j.oceram.2020.100003
SN - 2666-5395
VL - 1
SP - 100003
PB - Elsevier Ltd.
AN - OPUS4-51013
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Choi, Ching-Yi
A1 - Lossada, F.
A1 - Walter, K.
A1 - Fleck-Kunde, T.
A1 - Behrens, S.
A1 - Meinelt, T.
A1 - Falkenhagen, Jana
A1 - Hiller, M.
A1 - Oschkinat, H.
A1 - Dallmann, A.
A1 - Taden, A.
A1 - Börner, H.G.
T1 - Organic transformation of lignin into mussel-inspired glues: next-generation 2K adhesive for setting corals under saltwater
N2 - The 2-methoxyphenol units (G-units) in lignin are modified by demethylation and oxidation to provide the activated lignin as one part of an advanced biobased two-component (2K) adhesive system, which exhibits promising shear strengths in dry and underwater applications. The activation of lignin is straightforward and generates quinones via demethylation and periodate oxidation. These act as Michael acceptors and react smoothly with multi-thiol-star polymers to yield thiol-catechol connectivities (TCCs). The mussel-inspired material platform acts as a very robust and versatile adhesive, combining low-cost and readily available lignin with multi-thiols to achieve outstanding adhesion strengths of up to 15 MPa in dry application. In particular, the 2K system is compatible with the marine biological environment and shows no acute toxicity to sensitive organisms such as fish eggs. Thus, one possible application of this material could be an adhesive for setting temperature-resistant corals in damaged reefs.
KW - Lignin modification
KW - Mussel-inspired adhesive systems
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594588
DO - https://doi.org/10.1039/d3gc03680d
SN - 1463-9270
SP - 1
EP - 15
PB - RSC
CY - Cambridge
AN - OPUS4-59458
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chowdhary, S.
A1 - Moschner, J.
A1 - Mikolajczak, D. J.
A1 - Becker, M.
A1 - Thünemann, Andreas
A1 - Kästner, Claudia
A1 - Klemczak, D.
A1 - Stegemann, A.-K.
A1 - Böttcher, C.
A1 - Metrangolo, P.
A1 - Netz, R. R.
A1 - Koksch, B.
T1 - The Impact of Halogenated Phenylalanine Derivatives on NFGAIL Amyloid Formation
N2 - The hexapeptide hIAPP22–27 (NFGAIL) is known as a crucial amyloid core sequence of the human islet amyloid polypeptide (hIAPP) whose aggregates can be used to better understand the wild‐type hIAPP′s toxicity to β‐cell death. In amyloid research, the role of hydrophobic and aromatic‐aromatic interactions as potential driving forces during the aggregation process is controversially discussed not only in case of NFGAIL, but also for amyloidogenic peptides in general. We have used halogenation of the aromatic residue as a strategy to modulate hydrophobic and aromatic‐aromatic interactions and prepared a library of NFGAIL variants containing fluorinated and iodinated phenylalanine analogues. We used thioflavin T staining, transmission electron microscopy (TEM) and small‐angle X‐ray scattering (SAXS) to study the impact of side‐chain halogenation on NFGAIL amyloid formation kinetics. Our data revealed a synergy between aggregation behavior and hydrophobicity of the phenylalanine residue. This study introduces systematic fluorination as a toolbox to further investigate the nature of the amyloid self‐assembly process.
KW - Small-angle X-ray scattering
KW - SAXS
KW - Nanoparticle
KW - Nanostructure
KW - Peptide
KW - Amyloid
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518632
DO - https://doi.org/10.1002/cbic.202000373
VL - 21
IS - 24
SP - 3544
EP - 3554
PB - Wiley
CY - Weinheim
AN - OPUS4-51863
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Chowdhary, S.
A1 - Schmidt, R. F.
A1 - Sahoo, A. K.
A1 - tom Dieck, T.
A1 - Hohmann, T.
A1 - Schade, B.
A1 - Brademann-Jock, Kerstin
A1 - Thünemann, Andreas
A1 - Netz, R. R.
A1 - Gradzielski, M.
A1 - Koksch, B.
T1 - Rational design of amphiphilic fluorinated peptides: evaluation of self-assembly properties and hydrogel formation
N2 - Advanced peptide-based nanomaterials composed of self-assembling peptides (SAPs) are of emerging interest in pharmaceutical and biomedical applications. The introduction of fluorine into peptides, in fact, offers unique opportunities to tune their biophysical properties and intermolecular interactions. In particular, the degree of fluorination plays a crucial role in peptide engineering as it can be used to control the characteristics of fluorine-specific interactions and, thus, peptide conformation and self-assembly. Here, we designed and explored a series of amphipathic peptides by incorporating the fluorinated amino acids (2S)-4-monofluoroethylglycine (MfeGly), (2S)-4,4-difluoroethylglycine (DfeGly) and (2S)-4,4,4-trifluoroethylglycine (TfeGly) as hydrophobic components. This approach enabled studying the impact of fluorination on secondary structure formation and peptide self-assembly on a systematic basis. We show that the interplay between polarity and hydrophobicity, both induced differentially by varying degrees of side chain fluorination, does affect peptide folding significantly. A greater degree of fluorination promotes peptide fibrillation and subsequent formation of physical hydrogels in physiological conditions. Molecular simulations revealed the key role played by electrostatically driven intra-chain and inter-chain contact pairs that are modulated by side chain fluorination and give insights into the different self-organization behaviour of selected peptides. Our study provides a systematic report about the distinct features of fluorinated oligomeric peptides with potential applications as peptide-based biomaterials.
KW - Small-angle X-ray scattering
KW - SAXS
KW - Amyloid
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-553504
DO - https://doi.org/10.1039/D2NR01648F
SN - 2040-3364
VL - 14
IS - 28
SP - 10176
EP - 10189
PB - Royal Society of Chemistry
AN - OPUS4-55350
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Christopher, I
A1 - Michalchuk, Adam
A1 - Pulham, C.
A1 - Morrison, C.
T1 - Towards Computational Screening for New Energetic Molecules: Calculation of Heat of Formation and Determination of Bond Strengths by Local Mode Analysis
N2 - The reliable determination of gas-phase and solid-state heats of formation are important considerations in energetic materials research. Herein, the ability of PM7 to calculate the gas-phase heats of formation for CNHO-only and inorganic compounds has been critically evaluated, and for the former, comparisons drawn with isodesmic equations and Atom equivalence methods. Routes to obtain solid-state heats of formation for a range of singlecomponent molecular solids, salts, and co-crystals were also evaluated. Finally, local vibrational mode analysis has been used to calculate bond length/force constant curves for seven different chemical bonds occurring in CHNO-containing molecules, which allow for rapid identification of the weakest bond, opening up great potential to rationalise decomposition pathways. Both metrics are important tools in rationalising the design of new energetic materials through computational screening processes.
KW - Energetic materials
KW - Density functional theory
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530371
DO - https://doi.org/10.3389/fchem.2021.726357
VL - 9
SP - 726357
AN - OPUS4-53037
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cordsmeier, Leo
A1 - Hahn, Marc Benjamin
T1 - DNA Stability in Biodosimetry, Pharmacy and DNA Based Data-Storage: Optimal Storage and Handling Conditions
N2 - DNA long-term stability and integrity is of importance for applications in DNA based bio-dosimetry, data-storage, pharmaceutical quality-control, donor insemination and DNA based functional nanomaterials. Standard protocols for these applications involve repeated freeze-thaw cycles of the DNA, which can cause detrimental damage to the nucleobases, as well as the sugar-phosphate backbone and therefore the whole molecule. Throughout the literature three hypotheses can be found about the underlying mechanisms occurring during freeze-thaw cycles. It is hypothesized that DNA single-strand breaks during freezing can be induced by mechanical stress leading to shearing of the DNA molecule, by acidic pH causing damage through depurination and beta elimination or by the presence of metal ions catalyzing oxidative damage via reactive oxygen species (ROS). Here we test these hypotheses under well defined conditions with plasmid DNA pUC19 in high-purity buffer (1xPBS) at physiological salt and pH 7.4 conditions, under pH 6 and in the presence of metal ions in combination with the radical scavengers DMSO and Ectoine. The results show for the 2686 bp long plasmid DNA, that neither mechanical stress, nor pH 6 lead to degradation during repeated freeze-thaw cycles. In contrast, the presence of metal ions (Fe2+) leads to degradation of DNA via the production of radical species.
KW - DNA
KW - DNA stability
KW - Pharmacy
KW - Reference material
KW - pUC19
KW - Strand break
KW - SSB
KW - Dosimetry
KW - Biodosimetry
KW - Biologisches Dosimeter
KW - DNA Dosimeter
KW - Quality control
KW - Plasmid DNA
KW - DNA data storage
KW - Nucleobase
KW - Base damage
KW - Base loss
KW - DNA degradation
KW - Metal ions
KW - ROS
KW - OH radical
KW - Fenton Reaction
KW - H2O2
KW - DNA based data storage
KW - Freezing
KW - Thawing
KW - Mechanical stress
KW - pH
KW - Beta elimination
KW - Ectoine
KW - Ectoin
KW - THP(B)
KW - Radical scavenger
KW - DMSO
KW - Buffer
KW - lN2
KW - DNA vortexing
KW - AGE
KW - SYBR Gold
KW - Gel electrophoresis
KW - DNA long term storage
KW - DNA reference material
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557148
DO - https://doi.org/10.1002/cbic.202200391
SP - 1
EP - 9
PB - Wiley-VCH GmbH
AN - OPUS4-55714
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Costache, F.
A1 - Valette, S.
A1 - Bonse, Jörn
T1 - Editorial: Special Issue “Dynamics and Processes at Laser-Irradiated Surfaces—A Themed Issue in Honor of the 70th Birthday of Professor Jürgen Reif”
N2 - The Special Issue “Dynamics and Processes at Laser-irradiated Surfaces” is dedicated to the 70th birthday of Jürgen Reif, retired full professor, former Chair of Experimental Physics II of the Faculty of Physics of the Brandenburg University of Technology Cottbus—Senftenberg in Germany.
KW - Laser ablation
KW - Laser-induced periodic surface structures (LIPSS)
KW - Surface functionalization
KW - Femtosecond laser
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569482
DO - https://doi.org/10.3390/nano13030611
SN - 2079-4991
VL - 13
IS - 3
SP - 1
EP - 3
PB - MDPI
CY - Basel
AN - OPUS4-56948
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Crouzier, L.
A1 - Feltin, N.
A1 - Delvallée, A.
A1 - Pellegrino, Francesco
A1 - Maurino, V.
A1 - Cios, Grzegorz
A1 - Tokarski, T.
A1 - Salzmann, Christoph
A1 - Deumer, J.
A1 - Gollwitzer, C.
A1 - Hodoroaba, Vasile-Dan
T1 - Correlative analysis of the dimensional properties of bipyramidal titania nanoparticles by complementing electron microscopy with other methods
N2 - In this paper, the accurate determination of the size and size distribution of bipyramidal anatase nanoparticles (NPs) after deposition as single particles on a silicon substrate by correlative Scanning Electron Microscopy (SEM) with Atomic Force Microscopy (AFM) analysis is described as a new measurement procedure for metrological purposes. The knowledge of the exact orientation of the NPs is a crucial step in extracting the real 3D dimensions of the particles. Two approaches are proposed to determine the geometrical orientation of individual nano‐bipyramides: (i) AFM profiling along the long bipyramid axis and (ii) stage tilting followed by SEM imaging. Furthermore, a recently developed method, Transmission Kikuchi Diffraction (TKD), which needs preparation of the crystalline NPs on electron‐transparent substrates such as TEM grids, has been tested with respect to its capability of identifying the geometrical orientation of the individual NPs. With the NPs prepared homogeneously on a TEM grid, the transmission mode in a SEM, i.e., STEM‐in‐SEM (or T‐SEM), can be also applied to extract accurate projection dimensions of the nanoparticles from the same sample area as that analysed by SEM, TKD and possibly AFM. Finally, Small Angle X‐ray Scattering (SAXS) can be used as an ensemble technique able to measure the NPs in liquid suspension and, with ab‐initio knowledge of the NP shape from the descriptive imaging techniques, to provide traceable NP size distribution and particle concentration.
KW - Nanoparticles
KW - Complex-shape
KW - Bipyramid
KW - Electron microscopy
KW - AFM
KW - Size measurements
KW - TKD
KW - STEM-in-SEM
KW - SAXS
KW - Nanoparticle concentration
KW - Correlative analysis
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539888
DO - https://doi.org/10.3390/nano11123359
SN - 2079-4991
VL - 11
IS - 12
SP - 1
EP - 19
PB - MDPI
CY - Basel
AN - OPUS4-53988
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cubero, A.
A1 - Martínez, E.
A1 - Angurel, L.A.
A1 - de la Fuente, G.F.
A1 - Navarro, R.
A1 - Legall, Herbert
A1 - Krüger, Jörg
A1 - Bonse, Jörn
T1 - Surface superconductivity changes of niobium sheets by femtosecond laser-induced periodic nanostructures
N2 - Irradiation with ultra-short (femtosecond) laser beams enables the generation of sub-wavelength laser-induced periodic surface structures (LIPSS) over large areas with controlled spatial periodicity, orientation, and depths affecting only a material layer on the sub-micrometer scale. This study reports on how fs-laser irradiation of commercially available Nb foil samples affects their superconducting behavior. DC magnetization and AC susceptibility measurements at cryogenic temperatures and with magnetic fields of different amplitude and orientation are thus analyzed and reported. This study pays special attention to the surface superconducting layer that persists above the upper critical magnetic field strength Hc2, and disappears at a higher nucleation field strength Hc3. Characteristic changes were distinguished between the surface properties of the laser-irradiated samples, as compared to the corresponding reference samples (non-irradiated). Clear correlations have been observed between the surface nanostructures and the nucleation field Hc3, which depends on the relative orientation of the magnetic field and the surface patterns developed by the laser irradiation.
KW - Niobium
KW - Surface superconductivity
KW - Laser-induced periodic surface structures (LIPSS)
KW - Nanostructures
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518462
DO - https://doi.org/10.3390/nano10122525
SN - 2079-4991
VL - 10(12)
IS - Special issue "Laser-generated periodic nanostructures"
SP - 1
EP - 16
PB - MDPI
CY - Basel
AN - OPUS4-51846
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Cubero, A.
A1 - Martínez, E.
A1 - Angurel, L.A.
A1 - de la Fuente, G.F.
A1 - Navarro, R.
A1 - Legall, Herbert
A1 - Krüger, Jörg
A1 - Bonse, Jörn
T1 - Effects of laser-induced periodic surface structures on the superconducting properties of Niobium
N2 - It is well known that the use of ultrashort (fs) pulsed lasers can induce the generation of (quasi-) periodic nanostructures (LIPSS, ripples) on the surface of many materials. Such nanostructures have also been observed in sample’s surfaces irradiated with UV lasers with a pulse duration of 300 ps. In this work, we compare the characteristics of these nanostructures on 1-mm and on 25-μm thick niobium sheets induced by 30 fs n-IR and 300 ps UV pulsed lasers. In addition to conventional continuous or burst mode processing configurations, two-dimensional laser beam and line scanning modes have been investigated in this work. The latter allows the processing of large areas with a more uniform distribution of nanostructures at the surface. The influence of the generated nanostructures on the superconducting properties of niobium has also been explored. For this aim, magnetic hysteresis loops have been measured at different cryogenic temperatures to analyse how these laser treatments affect the flux pinning behaviour and, in consequence, the superconductor’s critical current values. It was observed that laser treatments are able to modify the superconducting properties of niobium samples.
T2 - E-MRS Spring Meeting 2019
CY - Nice, France
DA - 27.05.2019
KW - Superconductivity
KW - Laser-induced periodic surface structures (LIPSS)
KW - Niobium
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-502541
DO - https://doi.org/10.1016/j.apsusc.2019.145140
SN - 0169-4332
SN - 1873-5584
VL - 508
IS - 1
SP - 145140-1
EP - 145140-7
PB - Elsevier
CY - Amsterdam
AN - OPUS4-50254
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 - Dalgic, Mete-Sungur
A1 - Weidner, Steffen
T1 - Solvent-free sample preparation for matrix-assisted laserdesorption/ionization time-of-flight mass spectrometry ofpolymer blends
N2 - Solvent-free sample preparation offers some advantages over solvent-based techniques, such as improved accuracy, reproducibility and sensitivity, for matrix-assisted laser desorption/ionization (MALDI) analysis. However, little or no information is available on the application of solvent-free techniques for the MALDI analysis of polymer blends. Solvent-free sample preparation by ball milling was applied with varying sample-to-matrix ratios for MALDI time-of-flight mass spectrometry analysis of various polymers, including polystyrenes, poly(methyl methacrylate)s and poly(ethylene glycol)s. The peak intensity ratios were compared with those obtained after using the conventional dried droplet sample preparation method. In addition, solvent-assisted milling was also applied to improve sample homogeneities.
Depending on the sample preparation method used, different peak intensity ratios were found, showing varying degrees of suppression of the signal intensities of higher mass polymers. Ball milling for up to 30 min was required to achieve constant intensity ratios indicating homogeneous mixtures. The use of wet-assisted grinding to improve the homogeneity of the blends was found to be disadvantageous as it caused partial degradation and mass-dependent segregation of the polymers in the vials.The results clearly show that solvent-free sample preparation must be carefully considered when applied to synthetic polymer blends, as it may cause additional problems with regard to homogeneity and stability of the blends.
KW - MALDI TOF MS
KW - Sample preparation
KW - Polymer blends
KW - Solvent-free
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598570
DO - https://doi.org/10.1002/rcm.9756
SN - 0951-4198
VL - 38
IS - 12
SP - 1
EP - 9
PB - Wiley online library
AN - OPUS4-59857
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Darvishi Kamachali, Reza
A1 - Wallis, Theophilius
A1 - Ikeda, Yuki
A1 - Saikia, U.
A1 - Ahmadian, A.
A1 - Liebscher, C.
A1 - Hickel, Tilmann
A1 - Maaß, Robert
T1 - Giant segregation transition as origin of liquid metal embrittlement in the Fe-Zn system
N2 - A giant Zn segregation transition is revealed using CALPHAD-integrated density-based modeling of segregation into Fe grain boundaries (GBs). The results show that above a threshold of only a few atomic percent Zn in the alloy, a substantial amount of up to 60 at.% Zn can segregate to the GB. We found that the amount of segregation abruptly increases with decreasing temperature, while the Zn content in the alloy required for triggering the segregation transition decreases. Direct evidence of the Zn segregation transition is obtained using high-resolution scanning transmission electron microscopy. Base on the model, we trace the origin of the segregation transition back to the low cohesive energy of Zn and a miscibility gap in Fe-Zn GB, arising from the magnetic ordering effect, which is confirmed by ab-initio calculations. We also show that the massive Zn segregation resulting from the segregation transition greatly assists with liquid wetting and reduces the work of separation along the GB. The current predictions suggest that control over Zn segregation, by both alloy design and optimizing the galvanization and welding processes, may offer preventive strategies against liquid metal embrittlement.
KW - CALPHAD
KW - Microstructure Design
KW - Grain boundary engineering
KW - Steels
KW - Density-based Model
KW - Segregation Engineering
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-584292
DO - https://doi.org/10.1016/j.scriptamat.2023.115758
SN - 1359-6462
SN - 1872-8456
VL - 238
SP - 1
EP - 5
PB - Elsevier
CY - Amsterdam
AN - OPUS4-58429
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Das, Chayanika
A1 - Kastania, Eleni
A1 - Witt, Julia
A1 - Özcan Sandikcioglu, Özlem
T1 - Corrosion protection properties of poly(4-vinyl pyridine) containing multilayer polymeric coatings on magnesium alloy AZ31
N2 - The aim of this study is to develop polymeric thin films for corrosion protection of magnesium alloy AZ31. As polymer matrix, poly(4-vinyl pyridine) (P4VP) is selected due to its semiconducting properties and protonic conductivity. Polyacrylic acid is tested as crosslinking layers to improve interfacial adhesion. The macroscopic corrosion properties of the multilayer coatings are investigated by means of electrochemical methods, such as linear sweep voltammetry and electrochemical impedance spectroscopy (EIS), in corrosive media simulating technical and biomedical applications. It is demonstrated that thin multilayer coatings can suppress the corrosion rates of magnesium alloys. To our best knowledge, this is the first demonstration of the use of P4VP as a conducting polymer film with protonic conductivity for corrosion protection of magnesium alloys.
KW - Multilayercoatings
KW - AZ31
KW - Corrosion protection
KW - Intrinsically conducting polymers
KW - Magnesium alloys
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-551799
DO - https://doi.org/10.1002/maco.202112708
SN - 0947-5117
VL - 73
IS - 3
SP - 427
EP - 435
PB - Wiley VHC-Verlag
AN - OPUS4-55179
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Das, Prasenjit
A1 - Chakraborty, Gouri
A1 - Friese, Nico
A1 - Roeser, Jérôme
A1 - Prinz, Carsten
A1 - Emmerling, Franziska
A1 - Schmidt, Johannes
A1 - Thomas, Arne
T1 - Heteropolyaromatic Covalent Organic Frameworks via One-Pot Multicomponent Reactions
N2 - Multicomponent reactions (MCRs) offer a platform to create different chemical structures and linkages for highly stable covalent organic frameworks (COFs). As an illustrative example, the multicomponent Povarov reaction generates 2,4-phenylquinoline from aldehydes and amines in the presence of electron-rich alkenes. In this study, we introduce a new domino reaction to generate unprecedented 2,3-phenylquinoline COFs in the presence of epoxystyrene. This work thus presents, for the first time, structural isomeric COFs produced by multicomponent domino and Povarov reactions. Furthermore, 2,3-phenylquinolines can undergo a Scholl reaction to form extended aromatic linkages. With this approach, we synthesize two thermally and chemically stable MCR-COFs and two heteropolyaromatic COFs using both domino and in situ domino and Scholl reactions. The structure and properties of these COFs are compared with the corresponding 2,4-phenylquinoline-linked COF and imine-COF, and their activity toward benzene and cyclohexane sorption and separation is investigated. The position of the pendant phenyl groups within the COF pore plays a crucial role in facilitating the industrially important sorption and separation of benzene over cyclohexane. This study opens a new avenue to construct heteropolyaromatic COFs via MCR reactions.
KW - COF
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604038
DO - https://doi.org/10.1021/jacs.4c02551
SP - 1
EP - 9
PB - American Chemical Society (ACS)
AN - OPUS4-60403
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 - de O. Primo, J.
A1 - Horsth, D.F.
A1 - de S. Correa, J.
A1 - Das, A.
A1 - Bittencourt, C.
A1 - Umek, P.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Radtke, Martin
A1 - Yusenko, Kirill
A1 - Zanetta, C.
A1 - Anaissi, F.J.
T1 - Synthesis and Characterization of Ag/ZnO Nanoparticles for Bacteria Disinfection in Water
N2 - n this study, two green synthesis routes were used for the synthesis of Ag/ZnO nanoparticles, using cassava starch as a simple and low-cost effective fuel and Aloe vera as a reducing and stabilizing agent. The Ag/ZnO nanoparticles were characterized and used for bacterial dis-
infection of lake water contaminated with Escherichia coli (E. coli). Characterization indicated the formation of a face-centered cubic structure of metallic silver nanoparticles with no insertion of Ag into the ZnO hexagonal wurtzite structure. Physicochemical and bacteriological analyses described in “Standard Methods for the Examination of Water and Wastewater” were used to evaluate the efficiency of the treatment. In comparison to pure ZnO, the synthesized Ag/ZnO nanoparticles showed high efficiencies against Escherichia coli (E. coli) and general coliforms present in the lake
water. These pathogens were absent after treatment using Ag/ZnO nanoparticles. The results indicate that Ag/ZnO nanoparticles synthesized via green chemistry are a promising candidate for the treatment of wastewaters contaminated by bacteria, due to their facile preparation, low-cost synthesis,and disinfection efficiency.
KW - Synchrotron
KW - BAMline
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-562440
DO - https://doi.org/10.3390/nano12101764
SN - 2079-4991
VL - 12
IS - 10
SP - 1
EP - 18
PB - MDPI
CY - Basel
AN - OPUS4-56244
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira Guilherme Buzanich, Ana
T1 - Recent developments of X-ray absorption spectroscopy as analytical tool for biological and biomedical applications
N2 - X-ray absorption spectroscopy (XAS), in its various modalities, has gained exponential attention and applicability in the field of biological and biomedical systems. Particularly in this field, challenges like low concentration of analyte or proneness to radiation damage have certainly settle the basis for further analytical developments, when using X-ray based methods. Low concentration calls for higher sensitivity—by increasing the detection limits (DL); while susceptibility for radiation damage requires shorter measurement times and/or cryogenic sample environment possibilities. This manuscript reviews the latest analytical possibilities that make XAS more and more adequate to investigate biological or biomedical systems in the last 5 years.
KW - Biological & biomedical applications
KW - TXRF-XAS
KW - HERFD-XAS
KW - RXES
KW - Quick-XAS
KW - Dispersive-XAS
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531206
DO - https://doi.org/10.1002/xrs.3254
SN - 0049-8246
VL - 51
IS - 3
SP - 1
EP - 10
PB - John Wiley & Sons Ltd
AN - OPUS4-53120
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Cakir, Cafer Tufan
A1 - Radtke, Martin
A1 - Haider, M. Bilal
A1 - Emmerling, Franziska
A1 - F. M. Oliveira, P.
A1 - Michalchuk, Adam A. L.
T1 - Dispersive x-ray absorption spectroscopy for time-resolved in situ monitoring of mechanochemical reactions
N2 - X-ray absorption spectroscopy (XAS) provides a unique, atom-specific tool to probe the electronic structure of solids. By surmounting long-held limitations of powder-based XAS using a dynamically averaged powder in a Resonant Acoustic Mixer (RAM), we demonstrate how time-resolved in situ (TRIS) XAS provides unprecedented detail of mechanochemical synthesis. The use of a custom-designed dispersive XAS (DXAS) setup allows us to increase the time resolution over existing fluorescence measurements from ∼15 min to 2 s for a complete absorption spectrum. Hence, we here establish TRIS-XAS as a viable method for studying mechanochemical reactions and sampling reaction kinetics. The generality of our approach is demonstrated through RAM-induced (i) bottom-up Au nanoparticle mechanosynthesis and (ii) the synthesis of a prototypical metal organic framework, ZIF-8. Moreover, we demonstrate that our approach also works with the addition of a stainless steel milling ball, opening the door to using TRIS-DXAS for following conventional ball milling reactions. We expect that our TRIS-DXAS approach will become an essential part of the mechanochemical tool box.
KW - In situ studies
KW - Dipsersive XAS
KW - Mechanochemistry
KW - Time-resolved
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567659
DO - https://doi.org/10.1063/5.0130673
SN - 1089-7690
VL - 157
IS - 21
SP - 1
EP - 12
PB - American Institute of Physics
CY - Melville, NY
AN - OPUS4-56765
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira, P. F. M.
A1 - Torresi, R.
A1 - Emmerling, Franziska
A1 - Carmago, P.
T1 - Challenges and opportunities in the bottom-up mechanochemical synthesis of noble metal nanoparticles
N2 - Mechanochemistry is a promising alternative to solution-based protocols across the chemical sciences, enabling different types of chemistries in solvent-free and environmentally benign conditions. The use of mechanical energy to promote physical and chemical transformations has reached a high level of refinement, allowing for the design of sophisticated molecules and nanostructured materials. Among them, the synthesis of noble metal nanoparticles deserves special attention due to their catalytic applications. In this review, we discuss the recent progress on the development of mechanochemical strategies for the controlled synthesis of noble metal nanostructures. We start by covering the fundamentals of different preparation routes, namely top-down and bottom-up approaches. Next, we focus on the key examples of the mechanochemical synthesis of non-supported and supported metal nanoparticles as well as hybrid nanomaterials containing noble metals. In these examples, in addition to the principles and synthesis mechanisms, their performances in catalysis are discussed. Finally, a perspective of the field is given, where we discuss the opportunities for future work and the challenges of mechanochemical synthesis to produce well-defined noble metal nanoparticles.
KW - Mechanochemistry
KW - Nanoparticles
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-512080
DO - https://doi.org/10.1039/D0TA05183G
VL - 8
IS - 32
SP - 16114
AN - OPUS4-51208
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Deumer, J.
A1 - Pauw, Brian Richard
A1 - Marguet, S.
A1 - Skroblin, D.
A1 - Taché, O.
A1 - Krumrey, M.
A1 - Gollwitzer, C.
T1 - Small-angle X-ray scattering: characterization of cubic Au nanoparticles using Debye’s scattering formula
N2 - A versatile software package in the form of a Python extension, named CDEF (computing Debye’s scattering formula for extraordinary form factors), is proposed to calculate approximate scattering profiles of arbitrarily shaped nanoparticles for small-angle X-ray scattering (SAXS). CDEF generates a quasi-randomly distributed point cloud in the desired particle shape and then applies the open-source software DEBYER for efficient evaluation of Debye’s scattering formula to calculate the SAXS pattern (https://github.com/j-from-b/CDEF). If self-correlation of the scattering signal is not omitted, the quasi-random distribution provides faster convergence compared with a true-random distribution of the scatterers, especially at higher momentum transfer. The usage of the software is demonstrated for the evaluation of scattering data of Au nanocubes with rounded edges, which were measured at the four-crystal monochromator beamline of PTB at the synchrotron radiation facility BESSY II in Berlin. The implementation is fast enough to run on a single desktop computer and perform model fits within minutes. The accuracy of the method was analyzed by comparison with analytically known form factors and verified with another implementation, the SPONGE, based on a similar principle with fewer approximations. Additionally, the SPONGE coupled to McSAS3 allows one to retrieve information on the uncertainty of the size distribution using a Monte Carlo uncertainty estimation algorithm.
KW - X-ray scattering
KW - SAXS
KW - Non-spherical nanoparticles
KW - Nanoparticles
KW - Nanomaterials
KW - Debye scattering equation
KW - Simulation
KW - Data fitting
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557652
DO - https://doi.org/10.1107/S160057672200499X
VL - 55
IS - Pt 4
SP - 993
EP - 1001
PB - International Union of Crystallography
CY - Chester, England
AN - OPUS4-55765
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dhamo, Lorena
A1 - Carulli, F.
A1 - Nickl, Philip
A1 - Wegner, Karl David
A1 - Hodoroaba, Vasile-Dan
A1 - Würth, Christian
A1 - Brovelli, S.
A1 - Resch-Genger, Ute
T1 - Efficient luminescent solar concentrators based on environmentally friendly Cd-free ternary AIS/ZnS quantum dots
N2 - Luminescent solar concentrators (LSC) allow to obtain renewable energy from building integrated photovoltaic systems. As promising efficient and long-term stable LSC fluorophores semiconductor nanocrystals like Quantum dots (QDs) with size and composition tunable optoelectronic properties have recently emerged. The most popular II/VI or IV/VI semiconductor QDs contain, however, potentially hazardous cadmium or lead ions, which is a bottleneck for commercial applications. A simple aqueous based, microwaveassisted synthesis for environmentally friendly and highly emissive AgInS2/ ZnS QDs is developed using 3-mercaptopropionic acid (MPA) and glutathione (GSH) and their incorporation into polylaurylmethacrylate (PLMA) polymer slabs integrable in LSC devices (10.4 × 10.4 × 0.2 cm3, G = 12.98).
With this simple approach, optical power efficiencies (OPE) of 3.8% and 3.6% and optical quantum efficiencies (OQE) of 24.1% and 27.4% are obtained, which are among the highest values yet reported.
KW - Solar energy
KW - Solar concentrator
KW - Quantum dots
KW - Advanced material
KW - Quantum yield
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529735
DO - https://doi.org/10.1002/adom.202100587
SN - 2195-1071
SN - 0935-9648
VL - 9
IS - 17
SP - 1
EP - 8
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-52973
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dhamo, Lorena
A1 - Wegner, Karl David
A1 - Würth, Christian
A1 - Häusler, I.
A1 - Hodoroaba, Vasile-Dan
A1 - Resch-Genger, Ute
T1 - Assessing the influence of microwave-assisted synthesis parameters and stabilizing ligands on the optical properties of AIS/ZnS quantum dots
N2 - Luminescent semiconductor quantum dots (QDs) are frequently used in the life and material sciences as reporter for bioimaging studies and as active components in devices such as displays, light-emitting diodes, solar cells, and sensors. Increasing concerns regarding the use of toxic elements like cadmium and lead, and hazardous organic solvents during QD synthesis have meanwhile triggered the search for heavy-metal free QDs using green chemistry syntheses methods. Interesting candidates are ternary AgInS2 (AIS) QDs that exhibit broad photoluminescence (PL) bands, large effective Stokes shifts, high PL quantum yields (PL QYs), and long PL lifetimes, which are particularly beneficial for applications such as bioimaging, white light-emitting diodes, and solar concentrators. In addition, these nanomaterials can be prepared in high quality with a microwave-assisted (MW) synthesis in aqueous solution. The homogeneous heat diffusion and instant temperature rise of the MW synthesis enables a better control of QD nucleation and growth and thus increases the batch-to-batch reproducibility. In this study, we systematically explored the MW synthesis of AIS/ZnS QDs by varying parameters such as the order of reagent addition, precursor concentration, and type of stabilizing thiol ligand, and assessed their influence on the optical properties of the resulting AIS/ZnS QDs. Under optimized synthesis conditions, water-soluble AIS/ZnS QDs with a PL QY of 65% and excellent colloidal and long-term stability could be reproducible prepared.
KW - Quantum dots
KW - Microwave-assisted synthesis
KW - AgInS
KW - Aqueous synthesis
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567091
DO - https://doi.org/10.1038/s41598-022-25498-3
SN - 2045-2322
VL - 12
IS - 1
SP - 1
EP - 11
PB - Nature Publishing Group
CY - London
AN - OPUS4-56709
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Diehn, S.
A1 - Zimmermann, B.
A1 - Tafintseva, V.
A1 - Seifert, S.
A1 - Bagcioglu, M.
A1 - Ohlson, M.
A1 - Weidner, Steffen
A1 - Fjellheim, S.
A1 - Kohler, A.
A1 - Kneipp, Janina
T1 - Combining Chemical Information From Grass Pollen in Multimodal Characterization
N2 - The analysis of pollen chemical composition is important to many fields, including agriculture, plant physiology, ecology, allergology, and climate studies. Here, the potential of a combination of different spectroscopic and spectrometric methods regarding the characterization of small biochemical differences between pollen samples was evaluated using multivariate statistical approaches. Pollen samples, collected from three populations of the grass Poa alpina, were analyzed using Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy, surface enhanced Raman scattering (SERS), and matrix assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS). The variation in the sample set can be described in a hierarchical framework comprising three populations of the same grass species and four different growth conditions of the parent plants for each of the populations. Therefore, the data set can work here as a model system to evaluate the classification and characterization ability of the different spectroscopic and spectrometric methods. ANOVA Simultaneous Component Analysis (ASCA) was applied to achieve a separation of different sources of variance in the complex sample set. Since the chosen methods and sample preparations probe different parts and/or molecular constituents of the pollen grains, complementary information about the chemical composition of the pollen can be obtained. By using consensus principal component analysis (CPCA), data from the different methods are linked together. This enables an investigation of the underlying global information, since complementary chemical data are combined. The molecular information from four spectroscopies was combined with phenotypical information gathered from the parent plants, thereby helping to potentially link pollen chemistry to other biotic and abiotic parameters.
KW - Pollen
KW - MALDI-TOF MS
KW - FTIR
KW - Raman
KW - Multivariate analyses
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504822
DO - https://doi.org/10.3389/fpls.2019.01788
VL - 10
SP - 1788
AN - OPUS4-50482
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Diehn, Sabrina
A1 - Zimmermann, B.
A1 - Bagcioglu, M.
A1 - Seifert, Stephan
A1 - Kohler, A.
A1 - Ohlson, M.
A1 - Fjellheim, S.
A1 - Weidner, Steffen
A1 - Kneipp, Janina
T1 - Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) shows adaption of grass pollen composition
N2 - MALDI time-of-flight mass spectrometry (MALDI-TOF MS) has become a widely used tool for the classification of biological samples. The complex chemical composition of pollen grains leads to highly specific, fingerprint-like mass spectra, with respect to the pollen species. Beyond the species-specific composition, the variances in pollen chemistry can be hierarchically structured, including the level of different populations, of environmental conditions or different genotypes. We demonstrate here the sensitivity of MALDI-TOF MS regarding the adaption of the chemical composition of three Poaceae (grass) pollen for different populations of parent plants by analyzing the mass spectra with partial least squares discriminant analysis (PLS-DA) and principal component analysis (PCA). Thereby, variances in species, population and specific growth conditions of the plants were observed simultaneously. In particular, the chemical pattern revealed by the MALDI spectra enabled discrimination of the different populations of one species. Specifically, the role of environmental changes and their effect on the pollen chemistry of three different grass species is discussed. Analysis of the Group formation within the respective populations showed a varying influence of plant genotype on the classification, depending on the species, and permits conclusions regarding the respective rigidity or plasticity towards environmental changes.
KW - Pollen
KW - MALDI-TOF MS
KW - Classification
KW - Partial least square discriminant analysis (PLS-DA)
KW - Principal component analysis (PCA)
PY - 2018
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-465294
DO - https://doi.org/10.1038/s41598-018-34800-1
SN - 2045-2322
VL - 8
IS - 1
SP - 16591, 1
EP - 11
PB - Nature
AN - OPUS4-46529
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dittmann, D.
A1 - Saal, L.
A1 - Zietschmann, F.
A1 - Mai, M.
A1 - Altmann, Korinna
A1 - Al-Sabbagh, Dominik
A1 - Schuhmann, P.
A1 - Ruhl, A.
A1 - Jekel, M.
A1 - Braun, U.
T1 - Characterization of activated carbons for water treatment using TGA‑FTIR for analysis of oxygen‑containing functional groups
N2 - Water treatment with activated carbon (AC) is an established method for the removal of organic micropollutants and natu ral organic matter. However, it is not yet possible to predict the removal of individual pollutants. An appropriate material characterization, matching adsorption processes in water, might be the missing piece in the puzzle. To this end, this study examined 25 diferent commercially available ACs to evaluate their material properties. Frequently reported analyses, including N2 adsorption/desorption, CHNS(O), point of zero charge (PZC) analysis, and X-ray photoelectron spectroscopy, were conducted on a selected subset of powdered ACs. Inorganic elements examined using X-ray fuorescence and X-ray difraction spectroscopy revealed that relative elemental contents were distinctive to the individual AC’s raw material and activation procedure. This study also is the frst to use thermogravimetric analysis (TGA) coupled to Fourier-transform infrared spectroscopy (FTIR) to conduct quantitative analyses of functional surface oxygen groups (SOGs: carboxylic acid, anhydride, lactone, phenol, carbonyl, and pyrone groups) on such a large number of ACs. The comparably economical TGA method was found to provide good surrogates for the PZC by pyrolytic mass loss up to 600 ◦C (ML600), for the oxygen content by ML1000 and for the carbon content by oxidation. Mass loss profles depict the AC’s chemistry like fngerprints. Furthermore, we found that SOG contents determined by TGA-FTIR covered a wide individual range and depended on the raw material and production process of the AC. TGA and TGA-FTIR might therefore be used to identify the suitability of a particular AC for a variety of target substances in diferent target waters. This can help practitioners to control AC use in waterworks or wastewater treatment plants.
KW - Adsorbtion
KW - Organic contaminants
KW - Temperature-programmed desorption
KW - Proximate analysis
KW - Principal component analysis
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-555506
DO - https://doi.org/10.1007/s13201-022-01723-2
SN - 2190-5495
VL - 12
SP - 1
EP - 13
PB - Springer
CY - Berlin
AN - OPUS4-55550
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dittmann, Daniel
A1 - Eisentraut, Paul
A1 - Goedecke, Caroline
A1 - Wiesner, Yosri
A1 - Jekel, M
A1 - Ruhl, A S
A1 - Braun, Ulrike
T1 - Specific adsorption sites and conditions derived by thermal decomposition of activated carbons and adsorbed carbamazepine
N2 - The adsorption of organic micropollutants onto activated carbon is a favourable solution for the treatment of drinking water and wastewater. However, these adsorption processes are not sufficiently understood to allow for the appropriate prediction of removal processes. In this study, thermogravimetric analysis, alongside evolved gas analysis, is proposed for the characterisation of micropollutants adsorbed on activated carbon. Varying amounts of carbamazepine were adsorbed onto three different activated carbons, which were subsequently dried, and their thermal decomposition mechanisms examined. The discovery of 55 different pyrolysis products allowed differentiations to be made between specific adsorption sites and conditions. However, the same adsorption mechanisms were found for all samples, which were enhanced by inorganic constituents and oxygen containing surface groups. Furthermore, increasing the loadings led to the evolution of more hydrated decomposition products, whilst parts of the carbamazepine molecules were also integrated into the carbon structure. It was also found that the chemical composition, especially the degree of dehydration of the activated carbon, plays an important role in the adsorption of carbamazepine. Hence, it is thought that the adsorption sites may have a higher adsorption energy for specific adsorbates, when the activated carbon can then potentially increase its degree of graphitisation.
KW - Aktivkohle
KW - TED-GC/MS
KW - Adsorption
KW - Thermoanalytik
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506946
DO - https://doi.org/10.1038/s41598-020-63481-y
VL - 10
IS - 1
SP - 6695
PB - Nature Publishing Group
AN - OPUS4-50694
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dittmar, Stefan
A1 - Ruhl, Aki S.
A1 - Altmann, Korinna
A1 - Jekel, Martin
T1 - Settling Velocities of Small Microplastic Fragments and Fibers
N2 - There is only sparse empirical data on the settling velocity of small, non-buoyant microplastics thus far, although it is an important parameter governing their vertical transport within aquatic environments. This study reports the settling velocities of 4031 exemplary microplastic particles. Focusing on the environmentally most prevalent particle shapes, irregular microplastic fragments of four different polymer types (9–289 µm) as well as five discrete length fractions (50–600 µm) of common nylon and polyester fibers were investigated, respectively. All settling experiments were carried out in quiescent water using a specialized optical imaging setup. The method has been previously validated in order to minimize disruptive factors, e.g. thermal convection or particle interactions, and thus enable the precise measurements of the velocities of individual microplastic particles (0.003–9.094 mm/s). Based on the obtained data, ten existing models for predicting a particle’s terminal settling velocity were assessed. It is concluded that models, which were specifically deduced from empirical data on larger microplastics, fail to provide accurate predictions for small microplastics. Instead, a different approach is highlighted as a viable option for computing settling velocities across the microplastics continuum in terms of size, density and shape.
KW - Microplastics
KW - Microplastic fibers
KW - Settling velocity
KW - Sinking velocity
KW - Sedimentation
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597455
DO - https://doi.org/10.1021/acs.est.3c09602
SN - 0013-936X
VL - 58
IS - 14
SP - 6359
EP - 6369
PB - American Chemical Society (ACS)
AN - OPUS4-59745
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dobosy, Péter
A1 - Nguyen, Hoang Thi Phuong
A1 - Záray, Gyula
A1 - Streli, Christina
A1 - Ingerle, Dieter
A1 - Ziegler, Philipp
A1 - Radtke, Martin
A1 - Buzanich, Ana Guilherme
A1 - Endrédi, Anett
A1 - Fodor, Ferenc
T1 - Effect of iodine species on biofortification of iodine in cabbage plants cultivated in hydroponic cultures
N2 - Iodine is an essential trace element in the human diet because it is involved in the synthesis of thyroid hormones. Iodine deficiency affects over 2.2 billion people worldwide, making it a significant challenge to find plant-based sources of iodine that meet the recommended daily intake of this trace element. In this study, cabbage plants were cultivated in a hydroponic system containing iodine at concentrations ranging from 0.01 to 1.0 mg/L in the form of potassium iodide or potassium iodate. During the experiments, plant physiological parameters, biomass production, and concentration changes of iodine and selected microelements in different plant parts were investigated. In addition, the oxidation state of the accumulated iodine in root samples was determined. Results showed that iodine addition had no effect on photosynthetic efficiency and chlorophyll content. Iodide treatment did not considerably stimulate biomass production but iodate treatment increased it at concentrations less than 0.5 mg/L. Increasing iodine concentrations in the nutrient solutions increased iodine content in all plant parts; however, the iodide treatment was 2–7 times more efficient than the iodate treatment. It was concluded, that iodide addition was more favourable on the target element accumulation, however, it should be highlighted that application of this chemical form in nutrient solution decreased the concetrations of selected micoelement concentration comparing with the control plants. It was established that iodate was reduced to iodide during its uptake in cabbage roots, which means that independently from the oxidation number of iodine (+ 5, − 1) applied in the nutrient solutions, the reduced form of target element was transported to the aerial and edible tissues.
KW - BAMline
KW - XANES
KW - Synchrotron
KW - Lodine
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608330
DO - https://doi.org/10.1038/s41598-024-66575-z
VL - 14
IS - 1
SP - 1
EP - 12
PB - Springer Science and Business Media LLC
AN - OPUS4-60833
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Domonov, D.P.
A1 - Pechenyuk, S.I.
A1 - Semushina, Y.P.
A1 - Yusenko, Kirill
T1 - Solid state transformation in inner coordination sphere of [Co(NH3)6][Fe(C2O4)3]·3H2O as a route to access catalytically active Co-Fe materials
N2 - Thermal decomposition of [Co(NH₃)₆][Fe(C₂O₄)₃]∙3H₂O in argon atmosphere, at a low heating rate (3°/min), and in large amounts of the initial complex (~0.1 mole), has been studied. It was possible to distinguish four decomposition steps upon heating: In the temperature range of 50⁻100 °C-the loss of crystal water; 100⁻190 °C-stability region of dehydrated complex; 230⁻270 °C-the range of stability of intermediate phase with the formula CoFe(NH₃)₂(C₂O₄)₂; 270⁻350 °C-thermal decomposition of the intermediate with the formation of metallic products and further air oxidation with the formation of Co1.5Fe1.5O₄. Catalytic properties of thermolysis products were tested in the decomposition reaction of H₂O₂ (inactive), oxidation of acetone (average activity), and decomposition of ammonium perchlorate (highly active).
KW - Double complex salts
KW - Catalysts
KW - Single-source precursors
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-474014
DO - https://doi.org/10.3390/ma12020221
SN - 1996-1944
VL - 12
IS - 2
SP - 221, 1
EP - 10
PB - mdpi
CY - Zürich
AN - OPUS4-47401
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Donskyi, Ievgen
A1 - Nie, C.
A1 - Ludwig, K.
A1 - Trimpert, J.
A1 - Ahmed, R.
A1 - Quaas, E.
A1 - Achazi, K.
A1 - Radnik, Jörg
A1 - Adeli, M.
A1 - Haag, R.
A1 - Osterrieder, K.
T1 - Graphene Sheets with Defined Dual Functionalities for the Strong SARS-CoV-2 Interactions
N2 - Search of new strategies for the inhibition of respiratory viruses is one of the urgent health challenges worldwide, as most of the current therapeutic agents and treatments are inefficient. Severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) has caused a pandemic and has taken lives of approximately two Million people to date. Even though various vaccines are currently under development, virus, and especially its spike glycoprotein can mutate, which highlights a Need for a broad-spectrum inhibitor. In this work, inhibition of SARS-CoV-2 by graphene platforms with precise dual sulfate/alkyl functionalities is investigated. A series of graphene derivatives with different lengths of aliphatic chains is synthesized and is investigated for their ability to inhibit SARS-CoV-2 and feline coronavirus.
Graphene derivatives with long alkyl chains (>C9) inhibit coronavirus replication by virtue of disrupting viral envelope. The ability of these graphene platforms to rupture viruses is visualized by atomic force microscopy and cryogenic electron microscopy. A large concentration window (10 to 100-fold) where graphene platforms display strongly antiviral activity against native SARS-CoV-2 without significant toxicity against human cells is found. In this concentration range, the synthesized graphene platforms inhibit the infection of enveloped viruses efficiently, opening new therapeutic and metaphylactic avenues against SARS-CoV-2.
KW - Graphene
KW - Graphene-based polyglycerol sulfates
KW - SARS-CoV2 inhibitor
KW - Virucidality
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520858
DO - https://doi.org/10.1002/smll.202007091
VL - 17
IS - 11
SP - 7091
PB - Wiley VCH
AN - OPUS4-52085
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Driscoll, Laura L.
A1 - Driscoll, Elizabeth H.
A1 - Dong, Bo
A1 - Sayed, Farheen N.
A1 - Wilson, Jacob N.
A1 - O’Keefe, Christopher A.
A1 - Gardner, Dominic J.
A1 - Grey, Clare P.
A1 - Allan, Phoebe K.
A1 - Michalchuk, Adam A. L.
A1 - Slater, Peter R.
T1 - Under pressure: offering fundamental insight into structural changes on ball milling battery materials
N2 - Synthesis of Li ion battery materials via ball milling has been a huge area of growth, leading to new high-capacity electrode materials, such as a number of promising disordered rocksalt (DRS) phases. In prior work, it was generally assumed that the synthesis was facilitated simply by local heating effects during the milling process. In this work, we show that ball milling Li2MoO4 leads to a phase transformation to the high pressure spinel polymorph and we report electrochemical data for this phase. This observation of the formation of a high pressure polymorph shows that local heating effects alone cannot explain the phase transformation observed (phenakite to spinel) and so indicates the importance of other effects. In particular, we propose that when the milling balls collide with the material, the resulting shockwaves exert a localised pressure effect, in addition to local heating. To provide further support for this, we additionally report ball milling results for a number of case studies (Li2MnO3, Li2SnO3, Nb2O5) which reinforces the conclusion that local heating alone cannot explain the phase transformations observed. The work presented thus provides greater fundamental understanding of milling as a synthetic pathway and suggests potential strategies to prepare such samples without milling (e.g., doping to create internal chemical pressure). In addition, we suggest that further research is needed into the effect of the use of milling as a route to smaller particles, since we believe that such milling may also be affecting the surface structure of the particles through the influence of the shockwaves generated.
KW - Pollution
KW - Nuclear Energy and Engineering
KW - Sustainability and the Environment
KW - Environmental Chemistry
KW - Renewable Energy
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-590086
DO - https://doi.org/10.1039/d3ee00249g
VL - 16
IS - 11
SP - 5196
EP - 5209
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-59008
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Drobne, D.
A1 - Ciornii, Dmitri
A1 - Hodoroaba, Vasile-Dan
A1 - Bohmer, N.
A1 - Novak, S.
A1 - Kranjc, E.
A1 - Kononenko, V.
A1 - Reuther, R.
T1 - Knowledge, Information, and Data Readiness Levels (KaRLs) for Risk Assessment, Communication, and Governance of Nano-, New, and Other Advanced Materials
N2 - The obvious benefits derived from the increasing use of engineered nano-, new, and advanced materials and associated products have to be weighed out by a governance process against their possible risks. Differences in risk perception (beliefs about potential harm) among stakeholders, in particular nonscientists, and low transparency of the underlying decision processes can lead to a lack of support and acceptance of nano-, new, and other advanced material enabled products. To integrate scientific outcomes with stakeholders needs, this work develops a new approach comprising a nine-level, stepwise categorization and guidance system entitled “Knowledge, Information, and Data Readiness Levels” (KaRLs), analogous to the NASA Technology Readiness Levels. The KaRL system assesses the type, extent, and usability of the available data, information, and knowledge and integrates the participation of relevant and interested stakeholders in a cocreation/codesign process to improve current risk assessment, communication, and governance. The novelty of the new system is to communicate and share all available and relevant elements on material related risks in a user/stakeholder-friendly, transparent, flexible, and holistic way and so stimulate reflection, awareness, communication, and a deeper understanding that ultimately enables the discursive process that is needed for the sustainable risk governance of new materials.
KW - Risk asessment
KW - Advanced materials
KW - TRL
KW - Governance
KW - Data readiness level
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575344
DO - https://doi.org/10.1002/gch2.202200211
SP - 1
EP - 9
PB - Wiley-VCH
AN - OPUS4-57534
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dubey, A.
A1 - Hon Keat, C.
A1 - Shvartsman, V.
A1 - Yusenko, Kirill
A1 - Escobar, M.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Hagemann, U.
A1 - Kovalenko, S.
A1 - Stächler, J.
A1 - Lupascu, D.
T1 - Mono-, Di-, and Tri-valent Cation Doped BiFe0.95Mn0.05O3 Nanoparticles: Ferroelectric Photocatalysts
N2 - The ferroelectricity of multivalent co-doped Bismuth ferrite (BiFeO3; BFO) nanoparticles (NPs) is revealed and utilized for light photocatalysis exploiting their narrow electronic band gap. The photocatalytic activity of ferroelectric photocatalysts BiFe0.95Mn0.05O3 (BFM) NPs and mono-, di-, or tri-valent cations (Ag+, Ca2+, Dy3+; MDT) co-incorporated BFM NPs are studied under ultrasonication and in acidic conditions. We find that such doping enhances the photocatalytic activity of the ferroelectric NPs approximately three times. The correlation of the photocatalytic activity with structural, optical, and electrical properties of the doped NPs is established. The increase of spontaneous polarization by the mono- and tri-valent doping is one of the major factors in enhancing the photocatalytic performance along with other factors such as stronger light absorption in the visible range, low recombination rate of charge carriers and larger surface area of NPs. A-site doping of BFO NPs by divalent elements suppresses the polarization, whereas trivalent (Dy3+) and monovalent (Ag+) cations provide an increase of polarization. The depolarization field in these single domain NPs acts as a driving force to mitigate recombination of the photoinduced charge carriers.
KW - Piezoresponse
KW - Bismuth Ferrite
KW - Nanoparticles
KW - Photocatalysis
KW - Ferroelectric
KW - Polarization
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557230
DO - https://doi.org/10.1002/adfm.202207105
SN - 1616-301X
SP - 1
EP - 16
PB - Wiley
AN - OPUS4-55723
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dudziak, Mateusz
A1 - Bhatia, Riya
A1 - Dey, R.
A1 - Falkenhagen, Jana
A1 - Ullrich, M. S.
A1 - Thomsen, C.
A1 - Schartel, Bernhard
T1 - Wastewater phosphorus enriched algae as a sustainable flame retardant in polylactide
N2 - Revolutionizing our polymer industry for adaption to a sustainable carbon circular economy has become one of today’s most demanding challenges. Exploiting renewable resources to replace fossil-fuel—based plastics with biopolymers such as poly(lactic acid) (PLA) is inevitable while using waste streams as a raw material resource at least is promising. When it comes to using PLA as technical polymer, its high flammability must be addressed by flame retardants compatible with the thermoplastic processing of PLA and its compostability. This study proposes microalgae enriched with phosphorus from wastewater (P-Algae) as an elegant way towards a kind of sustainable organophosphorus flame retardant. The concept is demonstrated by investigating the processing, pyrolysis, flammability, and fire behavior of PLA/P-Algae, while varying the P-Algae content and comparing P-Algae with four alternative bio-fillers (phosphorylated lignin, biochar, thermally treated sewage sludge, and metal phytate) with different P-contents as meaningful benchmarks.
KW - PLA
KW - Flame Retardancy
KW - Phosphorylated Algae
KW - Wastewater flame retardants
KW - Zink phytate
KW - Phosphorylated lignin
KW - Thermally treated sludge
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604150
DO - https://doi.org/10.1016/j.polymdegradstab.2024.110885
SN - 1873-2321
SN - 0141-3910
VL - 227
SP - 1
EP - 11
PB - Elsevier Ltd.
AN - OPUS4-60415
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dudziak, Mateusz
A1 - Topolniak, Ievgeniia
A1 - Silbernagl, Dorothee
A1 - Altmann, Korinna
A1 - Sturm, Heinz
T1 - Long-time behavior of surface properties of microstructures fabricated by multiphoton lithography
N2 - The multiphoton lithography (MPL) technique represents the future of 3D microprinting, enabling the production of complex microscale objects with high precision. Although the MPL fabrication parameters are widely evaluated and discussed, not much attention has been given to the microscopic properties of 3D objects with respect to their surface properties and time-dependent stability. These properties are of crucial importance when it comes to the safe and durable use of these structures in biomedical applications. In this work, we investigate the surface properties of the MPL-produced SZ2080 polymeric microstructures with regard to the physical aging processes during the post-production stage. The influence of aging on the polymeric microstructures was investigated by means of Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). As a result, a time-dependent change in Young’s Modulus, plastic deformation, and adhesion and their correlation to the development in chemical composition of the surface of MPL-microstructures are evaluated. The results presented here are valuable for the application of MPL-fabricated 3D objects in general, but especially in medical technology as they give detailed information of the physical and chemical time-dependent dynamic behavior of MPL-printed surfaces and thus their suitability and performance in biological systems.
KW - Multiphoton lithography
KW - Additive manufacturing
KW - Microfabrication
KW - SZ2080 negative photo-resist
KW - Young´s modulus
KW - Aging
KW - Surface properties
KW - X-ray photoelectron spectroscopy
KW - Atomic force microscopy
KW - Force-distance-curve
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542166
DO - https://doi.org/10.3390/nano11123285
SN - 2079-4991
VL - 11
IS - 12
SP - 1
EP - 12
PB - MDPI
CY - Basel
AN - OPUS4-54216
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Edzards, Joshua
A1 - Saßnick, Holger-Dietrich
A1 - Buzanich, Ana Guilherme
A1 - Valencia, Ana M.
A1 - Emmerling, Franziska
A1 - Beyer, Sebastian
A1 - Cocchi, Caterina
T1 - Effects of Ligand Substituents on the Character of Zn-Coordination in Zeolitic Imidazolate Frameworks
N2 - Due to their favorable properties and high porosity, zeolitic imidazolate frameworks (ZIFs) have recently received much limelight for key technologies such as energy storage, optoelectronics, sensorics, and catalysis. Despite widespread interest in these materials, fundamental questions regarding the zinc coordination environment remain poorly understood. By focusing on zinc(II)2-methylimidazolate (ZIF-8) and its tetrahedrally coordinated analogues with Br-, Cl-, and H-substitution in the 2-ring position, we aim to clarify how variations in the local environment of Zn impact the charge distribution and the electronic properties of these materials. Our results from densityfunctional theory confirm the presence of a Zn coordinative bond with a large polarization that is quantitatively affected by different substituents on the organic ligand. Moreover, our findings suggest that the variations in the Zn coordination induced by the functionalization have a negligible effect on the electronic structure of the considered compounds. On the other hand, halogen terminations of the ligands lead to distinct electronic contributions in the vicinity of the frontier region which ultimately reduce the band gap size by a few hundred millielectron volts. Experimental results obtained from X-ray absorption spectroscopy (Zn K-edge) confirm the trends predicted by theory and, together with them, contribute to a better understanding of the structure−property relationships that are needed to tailor ZIFs for target applications.
KW - Surfaces
KW - Physical and Theoretical Chemistry
KW - General Energy
KW - Electronic
KW - Coatings and Films
KW - Optical and Magnetic Materials
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-589117
DO - https://doi.org/10.1021/acs.jpcc.3c06054
SN - 1932-7447
VL - 127
IS - 43
SP - 21456
EP - 21464
PB - American Chemical Society (ACS)
AN - OPUS4-58911
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Elert, Anna Maria
A1 - Chen, Yong-Cin
A1 - Smales, Glen J.
A1 - Topolniak, Ievgeniia
A1 - Sturm, Heinz
A1 - Schönhals, Andreas
A1 - Szymoniak, Paulina
T1 - Effects of the charge density of nanopapers based on carboxymethylated cellulose nanofibrils investigated by complementary techniques
N2 - Cellulose nanofibrils (CNFs) with different charge densities were prepared and investigated by a combination of different complementary techniques sensitive to the structure and molecular dynamics of the system. The morphology of the materials was investigated by scanning electron microscopy (SEM) and X-ray scattering (SAXS/WAXS). The latter measurements were quantitatively analyzed yielding to molecular parameters in dependence of the charge density like the diameter of the fibrils, the distance between the fibrils, and the dimension of bundles of nanofibrils, including pores. The influence of water on the properties and the charge density is studied by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and broadband dielectric spectroscopy. The TGA measurements reveal two mass loss processes. The one at lower temperatures was related to the loss of water, and the second process at higher temperatures was related to the chemical decomposition. The resulting char yield could be correlated to the distance between the microfibrils. The DSC investigation for hydrated CNFs revealed three glass transitions due to the cellulose segments surrounded by water molecules in different states. In the second heating scan, only one broad glass transition is observed. The dielectric spectra reveal two relaxation processes. At low temperatures or higher frequencies, the β-relaxation is observed, which is assigned to localized fluctuation of the glycosidic linkage. At higher temperatures and lower frequencies, the α-relaxation takes places. This relaxation is due to cooperative fluctuations in the cellulose segments. Both processes were quantitatively analyzed. The obtained parameters such as the relaxation rates were related to both the morphological data, the charge density, and the content of water for the first time.
KW - Cellulose nanofibrils
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600528
DO - https://doi.org/https://doi.org/10.1021/acsomega.4c00255
SN - 2470-1343
VL - 9
SP - 20152
EP - 20166
PB - ACS
AN - OPUS4-60052
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Elert, Anna Maria
A1 - Kanerva, M
A1 - Puolakka, A
A1 - Takala, T.M.
A1 - Mylläri, V
A1 - Jönkkäri, I
A1 - Sarlin, E
A1 - Seitsonen, J
A1 - Ruokolainen, J
A1 - Saris, P
A1 - Vuorinen, J
T1 - Antibacterial polymer fibres by rosin compounding and melt-spinning
N2 - The antibacterial features of natural pine/spruce rosin are well established, yet the functionality in various thermoplastics has not been surveyed. This work focuses on the processing of industrial grade purified rosin mixed with polyethylene (PE), polypropylene (PP), polylactic acid (PLA), polyamide (PA) and corn starch based biopolymer (CS). Homopolymer masterbatches were extrusion-compounded and melt-spun to form fibres for a wide range of products, such as filters, reinforcements, clothing and medical textiles. Due to the versatile chemical structure of rosin, it was observed compatible with all the selected polymers. In general, the rosin-blended systems were shear-thinning in a molten condition. The doped fibres spun of PE and PP indicated adequate melt-spinning capability and proper mechanical properties in terms of ultimate strength and Young's modulus. The antibacterial response was found dependent on the selected polymer. Especially PE with a 10 wt% rosin content showed significant antibacterial effects against Escherichia coli DH5α and Staphylococcus aureus ATCC 12598 when analysed in the Ringer's solution for 24 h.
KW - Rosin
KW - Antibacterial
KW - Thermoplastics
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-481785
DO - https://doi.org/10.1016/j.mtcomm.2019.05.003
SN - 2352-4928
VL - 20
SP - 527
EP - 527
PB - Elsevier
AN - OPUS4-48178
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Emamverdi, Farnaz
A1 - Huang, J.
A1 - Mosane Razavi, Negar
A1 - Bojdys, M. J.
A1 - Forster, A. B.
A1 - Budd, P. M.
A1 - Böhning, Martin
A1 - Schönhals, Andreas
T1 - Molecular Mobility and Gas Transport Properties of Mixed Matrix Membranes Based on PIM‑1 and a Phosphinine Containing Covalent Organic Framework
N2 - Polymers with intrinsic microporosity (PIMs) are gaining attention as gas separation membranes. Nevertheless, they face limitations due to pronounced physical aging. In this study a covalent organic framework containing λ5-phosphinine moieties, CPSF-EtO were incorporated as a nanofiller (concentration range 0-10 wt%) into a PIM-1 matrix forming dense films with a thickness of ca. 100 μm. The aim of the investigation was to investigate possible enhancements of gas transport properties and mitigating effects on physical aging. The incorporation of the nanofiller occurred on aggregate level with domains up to 100 nm as observed by T-SEM and confirmed by X-ray scattering. Moreover, the X-ray data show that the structure of the microporous network of the PIM-1 matrix is changed by the nanofiller.
As the molecular mobility is fundamental for gas transport as well as for physical aging, the study includes dielectric investigations of pure PIM-1 and PIM-1/CPSF-EtO mixed matrix membranes to establish a correlation between the molecular mobility and the gas transport properties. Using the time-lag method the gas permeability and the permselectivity were determined for N2, O2, CH4 and CO2 for samples with variation in filler content. A significant increase in the permeability of CH4 and CO2 (50 % increase compared to pure PIM-1) was observed for a concentration of 5 wt% of the nanofiller. Furthermore, the most pronounced change in the permselectivity was found for the gas pair CO2/N2 at a filler concentration of 7 wt%.
KW - Polymers of Intrinsic Microporosity
KW - Nanocomposites
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-595031
DO - https://doi.org/10.1021/acs.macromol.3c02419
SN - 0024-9297
VL - 57
IS - 4
SP - 1829
EP - 1845
PB - ACS Publications
AN - OPUS4-59503
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Emamverdi, Farnaz
A1 - Huang, J.
A1 - Szymoniak, Paulina
A1 - Bojdys, M. J.
A1 - Böhning, Martin
A1 - Schönhals, Andreas
T1 - Structure and molecular mobility of phosphinine-based covalent organic frameworks – glass transition of amorphous COFs
N2 - Two-dimensional covalent organic frameworks (COFs) based on phosphinine and thiophene building blocks have been synthesized with two different side groups. The materials are denoted as CPSF-MeO and CPSF-EtO where CxxF correspond to the covalent framework, whereas P and S are related to heteroatoms phosphorous and sulfur. MeO and EtO indicate the substituents, i.e. methoxy and ethoxy.
Their morphologies were studied by scanning electron microcopy and X-ray scattering. The absence of crystalline reflexes in the X-ray pattern reveal that both materials are amorphous and can be considered as glasses. Furthermore, N2 adsorption measurements indicate substantial Brunauer–Emmett–Teller (BET) surface area values pointing to the formation of three-dimensional pores by stacking of the aromatic 2D layer. An analysis of the porosity of both COFs showed a mean radius of the pores to be of ca. 4 nm, consistent with their chemical structure. The COFs form nanoparticles with a radius of around 100 nm. The thermal behavior of the COFs was further investigated by fast scanning calorimetry. These investigations showed that both COFs undergo a glass transition. The glass transition temperature of CPSF-EtO is found to be ca. 100 K higher than that for CPSF-MeO. This large difference in the glass transition is discussed to be due to a change in the interaction of the COF sheets induced by the longer ethoxy group. It might be assumed that for CPSF-EtO more individual COF sheets assemble to larger stacks than for CPSF-MeO. This agrees with the much larger surface area value found for CPSF-EtO compared to CPSF-MeO. To corroborate the results obtained be fast scanning calorimetry dielectric measurements were conducted which confirm the occurrence of a dynamic glass transition. The estimated temperature dependence of the relaxation rates of the dielectric relaxation and their absolute values agrees well with the data obtained by fast scanning calorimetry. Considering the fragility approach to the glass transition, it was further found that CPSF-MeO is a fragile glass former whereas CPSF-EtO behaves as a strong glass forming material. This difference in the fragility points also to distinct differences in the interaction between the 2D COF molecules in both materials.
KW - Covalent Organic frameworks
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-596770
DO - https://doi.org/10.1039/d3ma01123b
SP - 1
EP - 10
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-59677
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Emmerling, Franziska
A1 - Hoch, C.
T1 - Laudatio Prof. Dr.-Ing. Caroline Röhr
N2 - It is a laudatio on the ocations of Prof. Dr.-Ing. Caroline Röhrs 60th birthday.
KW - Metal-oxides
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561877
DO - https://doi.org/10.1002/zaac.202200159
SN - 0044-2313
VL - 648
IS - 10
SP - 1
EP - 2
PB - John Wiley & Sons, Ltd
AN - OPUS4-56187
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -