TY - CONF A1 - Heinekamp, Christian A1 - Emmerling, Franziska A1 - Braun, Thomas T1 - Metal fluoride surfaces by protonation with surface immobilized HF N2 - Lewis-acidic zirconium or chromium fluoride surfaces on different aluminium oxide or fluoride substrates. T2 - CRC 1349 Symposium 2021 CY - Berlin, Germany DA - 25.11.2021 KW - HF KW - Heterogeneous catalysis PY - 2021 AN - OPUS4-57226 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - de Oliveira Guilherme Buzanich, Ana A1 - Michalchuk, Adam A1 - Cakir, Cafer Tufan A1 - Haider, M. B. A1 - Yusenko, Kirill A1 - Radtke, Martin A1 - Reinholz, U. A1 - Emmerling, Franziska T1 - Time resolved in situ monitoring of mechanochemical transformations by X-ray spectroscopy (XAS) N2 - Mechanochemical reactions promise a new direction for environmentally benign preparation of materials, and has been dubbed by IUPAC as one of the 10 chemical innovations that will change our world. Despite this significant promise, very little is known about the mechanisms that drive mechanochemical transformations, posing significant barriers to realizing their full potential. To this end, there is growing need to follow mechanochemical reactions in situ and in real time. We here describe advances in the development and application of XAS methods to monitor material synthesis in real time under mechanochemical conditions. We demonstrate the generality of our approaches by describing mechanochemical syntheses of materials by both vibratory ball milling and by Resonant Acoustic Mixing (RAM), where a time resolution of 1 second is for a whole XAS spectrum was achieved. Moreover, we describe how spectroscopic methods can be coupled to diffraction-based approaches, thereby providing new dimensions in understanding mechanochemical synthesis. T2 - AfLS3 CY - Online meeting DA - 14.11.2021 KW - Dipsersive XAS KW - Mechanochemistry KW - Time-resolved KW - In situ PY - 2021 AN - OPUS4-56256 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - de Oliveira Guilherme Buzanich, Ana A1 - Michalchuk, Adam A1 - Cakir, Cafer Tufan A1 - Yusenko, Kirill A1 - Radtke, Martin A1 - Reinholz, U. A1 - Emmerling, Franziska T1 - Time resolved in situ monitoring of mechanochemical transformations by X-ray spectroscopy (XAS) N2 - Mechanochemical reactions promise a new direction for environmentally benign preparation of materials, and has been dubbed by IUPAC as one of the 10 chemical innovations that will change our world. Despite this significant promise, very little is known about the mechanisms that drive mechanochemical transformations, posing significant barriers to realizing their full potential. To this end, there is growing need to follow mechanochemical reactions in situ and in real time. We here describe advances in the development and application of XAS methods to monitor material synthesis in real time under mechanochemical conditions. We demonstrate the generality of our approaches by describing mechanochemical syntheses of materials by both vibratory ball milling and by Resonant Acoustic Mixing (RAM), where a time resolution of 1 second is for a whole XAS spectrum was achieved. Moreover, we describe how spectroscopic methods can be coupled to diffraction-based approaches, thereby providing new dimensions in understanding mechanochemical synthesis. T2 - Denver X-ray Conference: DXC 2021 CY - Online meeting DA - 02.08.2021 KW - Dispersive XAS KW - Mechanochemistry KW - Time resolved KW - In situ PY - 2021 AN - OPUS4-56257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fackeldey, K. A1 - Röhm, J. A1 - Niknejad, A. A1 - Chewle, Surahit A1 - Weber, M. T1 - Analyzing Raman spectral data without separabiliy assumption N2 - Raman spectroscopy is a well established tool for the analysis of vibration spectra, which then allow for the determination of individual substances in a chemical sample, or for their phase transitions. In the time-resolved-Raman-sprectroscopy the vibration spectra of a chemical sample are recorded sequentially over a time interval, such that conclusions for intermediate products (transients) can be drawn within a chemical process. The observed data-matrix M from a Raman spectroscopy can be regarded as a matrix product of two unknown matrices W and H, where the first is representing the contribution of the spectra and the latter represents the chemical spectra. One approach for obtaining W and H is the non-negative matrix factorization. We propose a novel approach, which does not need the commonly used separability assumption. The performance of this approach is shown on a real world chemical example. KW - Non-negative matrix factorization KW - NMF KW - Raman spectra KW - Separability condition KW - PCCA+ PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559051 DO - https://doi.org/10.1007/s10910-020-01201-7 SN - 1572-8897 VL - 59 SP - 575 EP - 596 PB - Springer Science + Business Media CY - Dordrecht AN - OPUS4-55905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emamverdi, Farnaz A1 - Yin, Huajie A1 - Schönhals, Andreas A1 - Böhning, Martin T1 - Molecular Mobility and Physical Aging of Polymers with Intrinsic Microporosity (PIM-1) Revisited: A Big Glassy World N2 - Polymeric membranes represent a cost- and energy-efficient solution for gas separation. Recently Polymers of Intrinsic Microporosity (PIMs) have been in a great interest because of their outstanding BET surface area larger than 700m2/g and pore size smaller than 1 nm. PIMs are a promising candidate in gas separation with high permeability and appealing selectivity due to their inefficient packing derived from a combination of ladder-like rigid segments with sites of contortion. However, it is recognized this class of polymers suffer from decrease in performance with time due to physical aging. The initial microporous structures approach a denser state via local chain rearrangements, leading to a dramatic reduction in permeability. As chain packing during film casting and physical aging are the key factors determine the performance in separation applications, characterization of the molecular mobility in these materials has been proved to provide valuable information. In recent research on PIM-1 the archetypal PIM, a molecular relaxation process with high activation energy together with a significant conductivity in the glassy state has been found and explained with the formation of local intermolecular agglomerates due to interaction of π-electrons in aromatic moieties of the polymer backbone. In this work, the dielectric behavior of the polymeric films and their response upon heating (aging) were measured by isothermal frequency scans during different heating/cooling cycles in a broad temperature range down to 133K for the first time. Multiple dielectric processes following Arrhenius behavior were observed. Local fluctuations, Maxwell-Wagner-Sillars (MWS) polarization and structural relaxations were discussed correlating to structural-properties of PIM-1. Up to now, no other work has studied the role of porosity and thermal history of PIM-1 film in dielectric processes. The goal is by eliminating thermal history and considering storing conditions provide better understanding on aging and plasticizing in high free volume glassy polymer PIM-1. T2 - IDS Online Meeting CY - Berlin, Germany DA - 06.09.2021 KW - Physical Aging KW - BDS KW - Microporous structure KW - Permeation PY - 2021 AN - OPUS4-55766 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emamverdi, Farnaz A1 - Yin, Huajie A1 - Schönhals, Andreas A1 - Böhning, Martin T1 - Molecular Mobility and Physical Aging of Polymers with Intrinsic Microporosity (PIM-1) Revisited: A Big Glassy World N2 - Polymeric membranes represent a cost- and energy-efficient solution for gas separation. Recently Polymers of Intrinsic Microporosity (PIMs) have been in a great interest because of their outstanding BET surface area larger than 700m2/g and pore size smaller than 1 nm. PIMs are a promising candidate in gas separation with high permeability and appealing selectivity due to their inefficient packing derived from a combination of ladder-like rigid segments with sites of contortion. However, it is recognized this class of polymers suffer from decrease in performance with time due to physical aging. The initial microporous structures approach a denser state via local chain rearrangements, leading to a dramatic reduction in permeability. As chain packing during film casting and physical aging are the key factors determine the performance in separation applications, characterization of the molecular mobility in these materials has been proved to provide valuable information. In recent research on PIM-1 the archetypal PIM, a molecular relaxation process with high activation energy together with a significant conductivity in the glassy state has been found and explained with the formation of local intermolecular agglomerates due to interaction of π-electrons in aromatic moieties of the polymer backbone. In this work, the dielectric behavior of the polymeric films and their response upon heating (aging) were measured by isothermal frequency scans during different heating/cooling cycles in a broad temperature range down to 133K for the first time. Multiple dielectric processes following Arrhenius behavior were observed. Local fluctuations, Maxwell-Wagner-Sillars (MWS) polarization and structural relaxations were discussed correlating to structural-properties of PIM-1. Up to now, no other work has studied the role of porosity and thermal history of PIM-1 film in dielectric processes. The goal is by eliminating thermal history and considering storing conditions provide better understanding on aging and plasticizing in high free volume glassy polymer PIM-1. T2 - Euromembrane conference CY - Copenhagen, Denmark DA - 29.11.2021 KW - Physical aging KW - Membrane KW - Microporous structure KW - Glassy polymer PY - 2021 AN - OPUS4-55758 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zvereva, V.V. A1 - Asanov, I.P. A1 - Yusenko, Kirill A1 - Zadesenec, A.V. A1 - Plyusnin, P.E. A1 - Gerasimov, E.Yu. A1 - Maksimovskiy, E.A. A1 - Korenev, S.V. A1 - Asanova, T.I. T1 - Local atomic and electronic structure of Pt‑Os nanoplates and nanofbers derived from the single‑source precursor (NH4)2[Pt0.5Os0.5Cl6] N2 - Abstract Nowadays, Pt-Os binary systems are mainly considered as catalysts and electrocatalysts, but the role of Os in these processes is still poorly understood. The electronic structure of Pt-Os nanosystems remains a few studied as well. Using bimetallic (NH4)2[Pt0.5Os0.5Cl6] as a single-source precursor for preparing Pt-Os nanoalloy through the thermal decomposition in hydrogen and inert atmospheres, the relation of morphology, atomic ordering, and electronic structure of Pt-Os nanoalloy was examined by in situ Quick XAFS, XPS, PXRD, SEM, and HRTEM techniques. Being the only variable parameter, the decomposition atmosphere was found to govern the morphology of the Pt-Os nanoalloy and change the atomic ordering (alloying extent), which involves a change in the electronic structure. In a hydrogen atmosphere, the nanofibers (NFs) (ø ~ 5–6 nm) with the atomic ordering Oscore&Pt-richshell were observed to form; in a nitrogen atmosphere, thin nanoplates (NPLs) (~ 12 nm) with the atomic architecture Os-richcore&Ptrichshell were found out. The depletion in the Os 5d5/2 and Pt 5d5/2,3/2 states was revealed for Pt-Os nanoalloys. This unusual result disagrees with the known d-band theory and indicates that there is a gain of non-d conduction electron counts at one or both sites. Mixed conductivity may exist in such Pt-Os nanoalloy that may be responsible for a manifestation of new physical properties of this binary system . KW - Bimetallic alloy KW - Nanoalloy KW - Synchrotron radiation KW - XAFS KW - Electronic structure KW - Alloy morphology PY - 2021 DO - https://doi.org/10.1007/s11051-021-05378-z SN - 1388-0764 VL - 24 IS - 1 SP - 1 EP - 23 PB - Springer AN - OPUS4-55347 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 - GEN A1 - George, Janine T1 - DFT-based Phonon-computations for "Considering the Role of Ion Transport in Diffuson-Dominated Thermal Conductivity" N2 - These are the harmonic phonon and Grüneisen parameter computations for the publication "Considering the Role of Ion Transport in Diffuson-Dominated Thermal Conductivity" (https://doi.org/10.1002/aenm.202200717). VASP and Phonopy outputs are included in this data set. KW - Thermal conductivity KW - Phonons PY - 2021 DO - https://doi.org/10.5281/zenodo.5116360 PB - Zenodo CY - Geneva AN - OPUS4-55168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zou, T. A1 - Nonappa, N. A1 - Khavani, M. A1 - Vuorte, M. A1 - Penttilä, P. A1 - Zitting, A. A1 - Valle-Delgado, J. J. A1 - Elert, Anna Maria A1 - Silbernagl, Dorothee A1 - Balakshin, M. A1 - Sammalkorpi, M. A1 - Österberg, M. T1 - Experimental and Simulation Study of the Solvent Effects on the Intrinsic Properties of Spherical Lignin Nanoparticles N2 - Spherical lignin nanoparticles (LNPs) fabricated via nanoprecipitation of dissolved lignin are among the most attractive biomass-derived nanomaterials. Despite various studies exploring the methods to improve the uniformity of LNPs or seeking more application opportunities for LNPs, little attention has been given to the fundamental aspects of the solvent effects on the intrinsic properties of LNPs. In this study, we employed a variety of experimental techniques and molecular dynamics (MD) simulations to investigate the solvent effects on the intrinsic properties of LNPs. The LNPs were prepared from softwood Kraft lignin (SKL) using the binary solvents of aqueous acetone or aqueous tetrahydrofuran (THF) via nanoprecipitation. The internal morphology, porosity, and mechanical properties of the LNPs were analyzed with electron tomography (ET), small-angle X-ray scattering (SAXS), atomic force microscopy (AFM), and intermodulation AFM (ImAFM). We found that aqueous acetone resulted in smaller LNPs with higher uniformity compared to aqueous THF, mainly ascribing to stronger solvent−lignin interactions as suggested by MD simulation results and confirmed with aqueous 1,4-dioxane (DXN) and aqueous dimethyl sulfoxide (DMSO). More importantly, we report that both LNPs were compact particles with relatively homogeneous density distribution and very low porosity in the internal structure. The stiffness of the particles was independent of the size, and the Young’s modulus was in the range of 0.3−4 GPa. Overall, the fundamental understandings of LNPs gained in this study are essential for the design of LNPs with optimal performance in applications. KW - Lignin KW - Electron tomography KW - Intermodulation AFM KW - Modulus KW - SAXS PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546948 DO - https://doi.org/10.1021/acs.jpcb.1c05319 SN - 1520-5207 VL - 125 IS - 44 SP - 12315 EP - 12328 PB - ACS AN - OPUS4-54694 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hodoroaba, Vasile-Dan A1 - Fagan, J. T1 - Contributors invited for two studies on concentration of bimodal silica nanoparticle and bipyramidal titania N2 - International standardisation network VAMAS is calling for participants in two studies on the measurement of (relative) number concentration of bimodal silica nanoparticles including deposition from liquid suspension and the measurement of particle size and shape distribution of bipyramidal titania including deposition from liquid suspension. KW - Nanoparticles KW - VAMAS KW - Inter-laboratory comparison KW - TiO2 KW - SiO2 PY - 2021 UR - https://www.iom3.org/resource/contributors-invited-for-two-studies-on-concentration-of-bimodal-silica-nanoparticle-and-bipyramidal-titania.html SP - 1 EP - 2 PB - Institute of Materials, Minerals and Mining (IOM3) CY - London, UK AN - OPUS4-54410 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emmerling, Franziska A1 - Martins, Ines T1 - Carbamazepine Dihydroxybenzoic Acid Cocrystals: Exploring Packing Interactions and Reaction Kinetics N2 - Herein, we present the mechanochemical formation of three new cocrystals containing the active pharmaceutical ingredient carbamazepine and dihydroxybenzoic acids as coformers (CBZ:2,4-DHBA 1:1, CBZ:2,5-DHBA 1:1, and CBZ:2,6-DHBA 1:1). Rietveld methods were used for three different purposes: (i) refining all structures solved using powder X-ray diffraction, (ii) performing a quantitative phase analysis of the diffraction data collected from ex situ mechanochemical reactions at different milling times, and (iii) determining the cocrystallization kinetic profiles. The rate of cocrystallization was found to be higher for the formation of CBZ:2,4-DHBA and CBZ:2,6-DHBA, reaching an equilibrium after 600 s of milling. In the case of CBZ:2,5-DHBA a short induction period of 20 s was detected prior to the start of the reaction and an equilibrium was reached after 1200 s. An empirical trend between the rate of cocrystallization and the structural complexity of the cocrystal product was found. The slowest cocrystallization rate observed for CBZ:2,5-DHBA corresponds to the crystal structure deviating substantially from the hydrogen-bonding motif found in the reactants. KW - Mechanochemistry KW - In situ real-time monitoring KW - Kinetics PY - 2021 DO - https://doi.org/10.1021/acs.cgd.1c00902 VL - 21 IS - 12 SP - 6961 EP - 6970 PB - ACS Publications AN - OPUS4-54407 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lakshmipathi, M. A1 - Tothadi, S. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Ghosh, S. T1 - Different mechanical responses of dimorphic forms of Anthracene Schiffbase crystal N2 - We obtained concomitant dimorphic forms of Anthracene Schiffbase (N-(anthracen-9-yl methylene)-2,5- dichloroaniline) from hexane solvent. Two polymorphs can be differentiated by their morphology and mechanical properties. One form is long acicular type and elastically bendable while another form is block shaped and brittle in nature. Mechanical property is attributed to underlying crystal packing. Hirsh- feld analysis and energy framework calculations were done to corroborate structure-property correlation of two forms. KW - Elasticity KW - Mechanical properties KW - Anthracene schiff base KW - Dimorphs PY - 2021 DO - https://doi.org/10.1016/j.molstruc.2021.132182 VL - 1252 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-54356 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manzoni, Anna Maria A1 - Dubois, F. A1 - Mousa, M. S. A1 - von Schlippenbach, C. A1 - Többens, D. M. A1 - Yesilcicek, Yasemin A1 - Zaiser, E. A1 - Hesse, René A1 - Haas, S. A1 - Glatzel, U. T1 - On the Formation of Eutectics in Variations of the Al10Co25Cr8Fe15Ni36Ti6 Compositionally Complex Alloy N2 - Superalloy inspired Al10Co25Cr8Fe15Ni36Ti6 compositionally complex alloy is known for its gamma-gamma' microstructure and the third Heusler phase. Variations of this alloy, gained by replacing 0.5 or 1 at. pct Al by the equivalent amount of Mo, W, Zr, Hf or B, can show more phases in addition to this three-phase morphology. When the homogenization temperature is chosen too high, a eutectic phase formation can take place at the grain boundaries, depending on the trace elements: Mo and W do not form eutectics while Hf, Zr and B do. In order to avoid the eutectic formation and the potential implied grain boundary weakening, the homogenization temperature must be chosen carefully by differential scanning calorimetry measurements. A too low homogenization temperature, however, could impede the misorientation alignment of the dendrites in the grain. The influence of grain boundary phases and incomplete dendrite re-orientation are compared and discussed. KW - High entropy alloy KW - Eutectic KW - Homogenization PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543504 DO - https://doi.org/10.1007/s11661-020-06091-7 VL - 52 IS - 1 SP - 143 EP - 150 PB - Springer AN - OPUS4-54350 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF ED - Hahn, Oliver ED - Doil, Thorsten T1 - Workshop Kulturguterhaltung - Vom Dampfkessel zu Nanomaterialien N2 - Sehr geehrte Damen und Herren, liebe Leserinnen und Leser, bereits im ersten Band der N.i.Ke. Schriftenreihe des Netzwerks zur interdisziplinären Kulturerhaltung hatte ich angeführt, dass bei der Untersuchung von kulturellen Artefakten naturwissenschaftliche Untersuchungsmethoden zunehmend an Bedeutung gewinnen, sie eigentlich unverzichtbar geworden sind. Ein besonders einprägsames Beispiel dieser fächerübergreifenden Zusammenarbeit zwischen Geisteswissenschaften, Naturwissenschaften und Restaurierungswissenschaften war die Ausstellung Johannes Vermeer. Vom Innehalten, die in diesem Jahr in der Gemäldegalerie Alter Meister in den staatlichen Kunstsammlungen Dresden gezeigt wurde. Eigens für diese Ausstellung wurde das Gemälde Brieflesendes Mädchen am offenen Fenster einer grundlegenden Restaurierung unterzogen. Diese Restaurierung diente jedoch nicht nur der Reparatur des Bildes. Um sich dem ursprünglichen Zustand des Gemäldes zwischen 1657 und 1659 anzunähern, wurden später hinzugefügte Malschichten großflächig abgenommen. Möglich wurde dies durch unterschiedliche, bildgebende materialwissenschaftliche Untersuchungen im Vorfeld, welche die wissenschaftlichen Grundlagen für die Diskussion über den weiteren Umgang mit der Lesenden schufen. Materialanalytische Verfahren wurden und werden ständig weiterentwickelt und optimiert. Sei es, um aus einer Vielzahl von Einzelmessungen ein Gesamtbild zu erstellen, oder die Größe einer Probenentnahme so zu reduzieren, dass von einer „minimal-invasiven“ oder „quasi nicht-invasiven“ Untersuchung ausgegangen werden kann. Nun feiert die Bundesanstalt für Materialforschung und -prüfung, zusammen mit ihren Vorgängerinstitutionen, den königlichen Versuchsanstalten, in diesem Jahr ihren einhundertfünfzigsten Geburtstag. Sie blickt damit auf eine lange Tradition materialwissenschaftlicher Analysen zurück, an deren Beginn beispielsweise die metallographischen Untersuchungen von Adolf Martens stehen. Derartige Untersuchungen bilden auch heute noch einen wesentlichen Bestandteil archäometallurgischer Forschung. Die Historie bzw. die Weiterentwicklung der Methodik lässt sich hier besonders gut nachzeichnen. Jedoch blicken auch Verfahren zur Charakterisierung weiterer Werkstoffe, wie Glas, Keramik, oder organischer Materialien auf eine lange Geschichte zurück. Die in diesem Band der N.i.Ke.-Schriftenreihe präsentierten Beiträge dokumentieren einerseits aktuelle Forschungsarbeiten, die erst in diesem Jahr in entsprechenden Fachjournalen publiziert wurden, andererseits liegen einige der Arbeiten bereits 50 Jahre zurück. Sie bekunden damit nicht nur die materialtechnologische und historische Bandbreite der Projekte, sondern offenbaren die Vielfältigkeit kulturhistorischer oder restauratorischer Fragestellungen, zu deren Beantwortung natur- und materialwissenschaftliche Forschung wesentliche Beiträge liefern können. Ich bedanke mich bei allen Kolleginnen und Kollegen, die zur Erstellung dieser dritten Ausgabe der N.i.Ke. Schriftenreihe des Netzwerks zur interdisziplinären Kulturerhaltung beigetragen haben. Ihre Aufsätze ermöglichen den Blick in die Vielfältigkeit materialwissenschaftlicher Untersuchungen im Bereich Kunst- und Kulturgut. Ich wünsche Ihnen viel Spaß auf dieser kleinen Zeitreise. T2 - Workshop Kulturguterhaltung - Vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Pergamonmuseums KW - Schriftrollen vom Toten Meer KW - Gold mit Synchrotronstrahlung KW - Kandelaber des Ensembles am Charlottenburger Tor KW - Berliner Tuffsteinfassaden KW - Betondickglasfenster des Glockenturms am Eiermannbau KW - Kaiser-Wilhelm-Gedächtniskirche KW - Radiografische Untersuchung PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543239 UR - https://netzwerke.bam.de/Netzwerke/Navigation/DE/Netzwerke/NIKE/nike.html VL - 3 SP - 1 EP - 155 PB - Druckerei G. Bohm CY - Berlin AN - OPUS4-54323 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - MacLean, J. A1 - Mayanna, S. A1 - Benning, L. G. A1 - Horn, F. A1 - Bartholomäus, A. A1 - Wiesner, Yosri A1 - Wagner, D. A1 - Liebner, S. T1 - The terrestrial plastisphere: Diversity and polymer-colonizing potential of plastic-associated microbial communities in soil N2 - The concept of a ‘plastisphere microbial community’ arose from research on aquatic plastic debris, while the effect of plastics on microbial communities in soils remains poorly understood. Therefore, we examined the inhabiting microbial communities of two plastic debris ecosystems with regard to their diversity and composition relative to plastic-free soils from the same area using 16S rRNA amplicon sequencing. Furthermore, we studied the plastic-colonizing potential of bacteria originating from both study sites as a measure of surface adhesion to UV-weathered polyethylene (PE) using high-magnification field emission scanning electron microscopy (FESEM). The high plastic content of the soils was associated with a reduced alpha diversity and a significantly different structure of the microbial communities. The presence of plastic debris in soils did not specifically enrich bacteria known to degrade plastic, as suggested by earlier studies, but rather shifted the microbial community towards highly abundant autotrophic bacteria potentially tolerant to hydrophobic environments and known to be important for biocrust formation. The bacterial inoculates from both sites formed dense biofilms on the surface and in micrometer-scale surface cracks of the UV-weathered PE chips after 100 days of in vitro incubation with visible threadlike EPS structures and cross-connections enabling surface adhesion. High-resolution FESEM imaging further indicates that the microbial colonization catalyzed some of the surface degradation of PE. In essence, this study suggests the concept of a ‘terrestrial plastisphere’ as a diverse consortium of microorganisms including autotrophs and other pioneering species paving the way for those members of the consortium that may eventually break down the plastic compounds. KW - Soil microbial community KW - Polyethylene colonization KW - Plastic pollution PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-542790 DO - https://doi.org/10.3390/microorganisms9091876 VL - 9 IS - 9 SP - 1 EP - 19 PB - MDPI CY - Basel AN - OPUS4-54279 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eisentraut, Paul A1 - Altmann, Korinna T1 - Repräsentative Mikroplastik-Detektion in Umweltproben - Weiterentwicklung der TED-GC/MS N2 - Die große Herausforderung in der Detektion von Mikroplastik (MP)‑Partikeln (1-1000 µm) besteht darin, sie neben Millionen von natürlichen Partikeln in Umweltproben nachzuweisen. Zum Aufspüren von Senken, Eintragspfaden und für Monitoring-Kampagnen ist ein schnelles, automatisiertes Verfahren unerlässlich. Ein solches Verfahren wurde an der Bundesanstalt für Materialforschung und -prüfung (BAM) mit der ThermoExtraktion/Desorption-Gaschromatographie-Massenspektrometrie (TED-GC/MS) in den letzten Jahren entwickelt. KW - Mikroplastik KW - TED-GC/MS PY - 2021 UR - https://analyticalscience.wiley.com/do/10.1002/was.0004000195 SN - 0016-3538 SP - 2 EP - 5 PB - Wiley-VCH CY - Weinheim AN - OPUS4-54266 LA - deu 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 - Kricheldorf, H. R. A1 - Weidner, Steffen A1 - Scheliga, F. T1 - Ring-Expansion Polymerization of 𝝐-Caprolactone, Glycolide, and l-lactide with a Spirocyclic Tin(IV) Catalyst Derived from or 2,2′-Dihydroxy-1,1′-Binaphthyl – New Results and a Revision N2 - In contrast to other cyclic tin bisphenoxides, polymerizations of glycolide and l-lactide with the spirocyclic tin(IV) bis-1,1′-bisnapthoxide yield linear chains having a 1,1′-bisnapthol end group and no cycles. In the case of l-lactide, LA/Cat ratio and temperature are varied and at 160 °C or below, all polylactides mainly consist of even-numbered chains. A total predominance of even-numbered chains is also found for homopolymerization of glycolide, or the copolymerization of glycolide and l-lactide, when conducted <120 °C. Linear chains having a bisnaphthol end group are again the main reaction products of ring-expansion polymerizations (REP) of 𝝐-caprolactone, but above 150 °C cycles are also formed. KW - Polylactide KW - MALDI-TOF MS KW - Polymerization PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-541931 DO - https://doi.org/10.1002/macp.202100308 VL - 222 IS - 24 SP - 1 EP - 10 PB - Wiley VCH GmbH AN - OPUS4-54193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kim, K.J. A1 - Kim, C.S. A1 - Ruh, S. W. A1 - Unger, Wolfgang A1 - Radnik, Jörg A1 - Mata-Salazar, J. A1 - Juarez-Garcia, J.M. A1 - Cortazar-Martinez, O. A1 - Herrera-Gomez, A. A1 - Hansen, P.E. A1 - Madesen, J.S. A1 - Senna, C.A. A1 - Archanjo, B.S. A1 - Damasceno, J.C. A1 - Achete, C.A. A1 - Wang, H. A1 - Wang, M. A1 - Windover, D. A1 - Steel, E. A1 - Kurokawa, A. A1 - Fujimoto, T. A1 - Azuma, Y. A1 - Terauchi, S. A1 - Zhang, L. A1 - Jordaan, W.A. A1 - Spencer, S.J. A1 - Shard, A.G. A1 - Koenders, L. A1 - Krumrey, M. A1 - Busch, I. A1 - Jeynes, C. T1 - Thickness measurement of nm HfO2 films N2 - A pilot study for the thickness measurement of HfO2 films was performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The aim of this pilot study was to ensure the equivalency in the measurement capability of national metrology institutes for the thickness measurement of HfO2 films. In this pilot study, the thicknesses of six HfO2 films with nominal thickness from 1 nm to 4 nm were measured by X-ray Photoelectron Spectroscopy (XPS), X-ray Reflectometry(XRR), X-ray Fluorescence Analysis (XRF), Transmission Electron Spectroscopy (TEM), Spectroscopic Ellipsometry (SE) and Rutherford Backscattering Spectrometry (RBS). The reference thicknesses were determined by mutual calibration of a zero-offset method (Medium Energy Ion Scattering Spectroscopy (MEIS) of KRISS) and a method traceable to the length unit (the average thicknesses of three XRR data except the thinnest film). These reference thicknesses are traceable to the length unit because they are based on the traceability of XRR. For the thickness measurement by XPS, the effective attenuation length of Hf 4f electrons was determined. In the cases of XRR and TEM, the offset values were determined from a linear fitting between the reference thicknesses and the individual data by XRR and TEM. The amount of substance of HfO2, expressed as thickness of HfO2 films (in both linear and areal density units), was found to be a good subject for a CCQM key comparison. To reach the main text of this paper, click on Final Report. The final report has been peer-reviewed and approved for publication by the CCQM. KW - Thickness measurements KW - nm films KW - X-ray Photoelectron Spectroscopy KW - Mutual calibration PY - 2021 DO - https://doi.org/10.1088/0026-1394/58/1A/08016 SN - 0026-1394 VL - 58 IS - 1a SP - 08016 PB - IOP Publishing Lt. CY - Bristol AN - OPUS4-54175 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lutz, C. A1 - Hampel, S. A1 - Beuermann, S. A1 - Turek, T. A1 - Kunz, U. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Fittschen, U. E. A. T1 - Investigation on Vanadium Species Distribution in Nafion™ 117 after Cyclization in a Vanadium Redox Flow Battery N2 - The vanadium redox flow battery (VRFB) is currently a potential candidate for stationary energy storage. A major challenge is the unintended vanadium transport through the separator, which results in a fade of capacity. To overcome this issue, it is necessary to understand the transport processes in the membrane on a more fundamental level. In this work, the vanadium species distribution in Nafion™ 117 after cyclization was investigated. Two membranes, one from a charged VRFB and another from a discharged VRFB, were analyzed using ultraviolet–visible spectroscopy (UV/VIS) and X-ray absorption near edge structure spectroscopy (XANES). Little difference between the two membranes was recognizable according to the UV/VIS results. In comparison, the XANES results showed that the membrane from the charged VRFB contains more V3+ than VO2+, whereas for the discharged case, more VO2+ is present in the membrane. KW - Synchrotron KW - BAMline KW - XANES KW - Vanadium redox flow battery PY - 2021 VL - 64 SP - 1 EP - 8 AN - OPUS4-54144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Iro, M. A1 - Ingerle, D. A1 - Radtke, Martin A1 - Tsuji, K. A1 - Hampel, S. A1 - Fittschen, U. A1 - Streli, C. T1 - Investigation of the transmission properties of a polycapillary half-lens and their effect on quantification for confocal μXRF N2 - Confocal Micro X-ray fluorescence analysis (μXRF) is a powerful method for the destruction-free investigation of the elemental composition of various samples in three dimensions. Quantitative results rely heavily on the transmission properties of polycapillary optics, used in confocal setups. Different models for the functional correlation between energy and transmission of a polycapillary half-lens are compared with experimental data, established with a monochromatic confocal laboratory setup [1], as well as Monte-Carlo-Simulations [2]. The effect of the different approaches on quantitative results are compared using well known SRMs, ranging from thick samples to thin layers and structured materials. Along with this the basic principles for quantitative evaluations of XRF spectra taken with confocal setups are presented, and compared with experimental results. T2 - Denver X-Ray Conference CY - Online meeting DA - 02.08.2021 KW - Synchrotron KW - BAMline KW - Polycapillaries PY - 2021 AN - OPUS4-54143 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - ML@BAMLINE N2 - An overview of the machine learning methods used at BAMline. Examples of automatic alignment and optimisation based on Gaussian processes are discussed. Quantification of XRF measurements and reconstruction for coded aperture imaging based on neural networks are also presented. T2 - Machine Learning Workshop BAM CY - Online meeting DA - 18.03.2021 KW - Artificial Intelligence KW - Machine learning KW - Bayesian Optimization KW - Gaussian process KW - Neural Network PY - 2021 AN - OPUS4-54142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Machine learning for direct quantification of XRF measurements N2 - In this talk I’ll describe the use of artificial neural networks (ANN) for quantifying X-ray fluorescence (XRF) measurements. The main idea of this talk is to give an overview of the process needed to generate a model that can then be applied to a specific problem. In XRF, a sample is excited with X-rays and the resulting characteristic radiation is detected to determine elements quantitatively and qualitatively. This is traditionally done in several time-consuming steps. I’ll show the possibilities and problems of using a neural network to realise a "one-click" quantification. This includes generating training data using Monte Carlo simulation and augmenting the existing data set with an ANN to generate more data. The search for the optimal hyperparameters, manually and automatically, is also described. For the case presented, we were able to train a network with a mean absolute error of 0.1% by weight for the synthetic data and 0.7% by weight for a set of experimental data obtained with certified reference materials. T2 - Seminar series: Artificial Intelligence applied to X-ray / synchrotron techniques CY - Online meeting DA - 24.06.2021 KW - Artificial intelligence KW - Machine learning KW - Synchrotron KW - XRF PY - 2021 AN - OPUS4-54140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - de Oliveira Guilherme Buzanich, Ana A1 - Reinholz, Uwe T1 - Das goldene Zeitalter war damals Analyse von Gold mit Synchrotronstrahlung N2 - Gold ist eines der sieben bereits in der Antike bekannten Metalle und wurde wegen seines Glanzes und seiner Seltenheit seit jeher als Tauschmittel und zur Herstellung von Schmuck verwendet. Außerdem ist es leicht zu bearbeiten und weitgehend resistent gegen chemische Einflüsse. Die Analyse von Gold mit der durch Synchrotronstrahlung angeregten Röntgenfluoreszenzanalyse ist zerstörungsfrei und liefert Informationen über die in der untersuchten Probe vorhandenen chemischen Elemente. Im Mittelpunkt der hier vorgestellten Untersuchungen an der BAMline stehen Fragen nach der Herkunft, dem Herstellungsprozess und der Zugehörigkeit von Goldfunden. Die verschiedenen Fragestellungen werden anhand einer Reihe von Beispielen erläutert, die vom Wikingerschatz von Hiddensee über die Himmelsscheibe von Nebra bis hin zu Funden aus Ägypten reichen. Darüber hinaus werden die heute am Synchrotron verfügbaren modernen Messmethoden vorgestellt. T2 - WISSENSCHAFT MIT WIRKUNG: Workshop Kulturguterhaltung – vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Gold KW - Synchrotron KW - Bernstorf KW - Nebra KW - XRF PY - 2021 AN - OPUS4-54139 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knigge, Xenia A1 - Radnik, Jörg T1 - 1-Propyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide (Solarpur®) analyzed by hard x-ray photoelectron spectroscopy N2 - 1-Propyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide (Solarpur®), an ionic liquid was purchased from Merck (formerly Sigma Aldrich), was analyzed using hard x-ray photoelectron spectroscopy (HAXPES). The liquid is UHV stable, vertically and laterally homogeneous, and is easy to clean; thus, it can be used as a reference material. The HAXPES spectra of Solarpur® obtained using monochromatic Cr Kα radiation at 5414.8 eV include a survey scan, high-resolution spectra of C 1s, O 1s, N 1s, S 2p, S 1s, S 2s, F 1s, and S KLL. KW - HAXPES KW - Hard x-ray photoelectron spectroscopy KW - Ionic liquid KW - Solarpur PY - 2021 DO - https://doi.org/10.1116/6.0001414 VL - 28 IS - 2 SP - 1 EP - 8 PB - AVS: Science & Technology of Materials, Interfaces, and Processing AN - OPUS4-54113 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - George, Janine T1 - Accelerated Materials Discovery Based on Data Analysis and Machine Learning N2 - The stability of materials is a very important property for materials discovery. In recent years, we have explored several approaches for advancing the prediction of the stability of crystals (e.g., classical chemical heuristics and machine-learned interatomic potentials). For example, we have assessed a famous chemical heuristic – the Pauling rules – regarding their usefulness for structure prediction. They are only of limited predictive power, i.e. the rules 2 to 5 only work for 13 % of all tested oxides. Furthermore, we have shown that machine-learned interatomic potentials can be used to predict phonon properties of a range of silicon allotropes accurately and, therefore, they can also be used to assess the dynamic stability of materials. To do so, we have developed new schemes to build reference databases for machine learned interatomic potentials. T2 - PACRIM & GOMD 2021 CY - Online meeting DA - 13.12.2021 KW - Data analysis KW - Machine learning KW - High-throughput computations PY - 2021 AN - OPUS4-54088 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - George, Janine T1 - Automation in Computational Materials Science N2 - This lecture illustrated the current state of automation in the field of computational materials science based on recent examples from my research. T2 - NOA Lecture Series FSU Jena CY - Jena, Germany DA - 02.11.2021 KW - Data analysis KW - Machine learning KW - High-throughput computations PY - 2021 AN - OPUS4-54089 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lee, P.-W. A1 - Kaynak, T. A1 - Al-Sabbagh, Dominik A1 - Emmerling, Franziska A1 - Schalley, C. T1 - Effect of Perfluorinated Side-Chain Length on the Morphology, Hydrophobicity, and Stability of Xerogel Coatings N2 - Superhydrophobic surfaces can be quickly formed with supramolecular materials. Incorporating low-molecular-weight gelators (LMWGs) with perfluorinated chains generates xerogel coatings with low surface energies and high roughness. Here, we examine and compare the properties of the xerogel coatings formed with eight different LMWGs. These LMWGs all have a trans-1,2-diamidocyclohexane core and two perfluorinated ponytails, whose lengths vary from three to ten carbon atoms (CF3 to CF10). Investigation of the xerogels aims to provide in-depth information on the chain length effect. LMWGs with a higher degree of fluorination (CF7 to CF10) form superhydrophobic xerogel coatings with very low surface energies. Scanning electron microscopy images of the coatings show that the aggregates of CF5 and CF7 are fibrous, while the others are crystal-like. Aggregates of CF10 are particularly small and further assemble into a porous structure on the micrometer scale. To test their stabilities, the xerogel coatings were flushed multiple times with a standardized water flush test. The removal of material from the surface in these flushes was monitored by a combination of the water contact angle, contact angle hysteresis, and coating thickness measurements. A new method based on image processing techniques was developed to reliably determine the change of the coating thickness. The CF7, CF9, and CF10 surfaces show consistent hydrophobicity and coating durability after repetitive flushing tests. The length of the perfluorinated side chains thus has a significant effect on the morphology of the deposited xerogel coatings, their roughness, and, in consequence, their hydrophobicity and mechanical durability. KW - Coating materials KW - Amorphous materials KW - Hydrophobicity KW - Materials Stability PY - 2021 DO - https://doi.org/10.1021/acs.langmuir.1c02341 SN - 1520-5827 VL - 37 IS - 49 SP - 14390 EP - 14397 PB - ACS Publications AN - OPUS4-54071 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Michna, A. A1 - Maciejewska-Prończuk, J. A1 - Wasilewska, M. A1 - Kilicer, Tayfun A1 - Witt, Julia A1 - Özcan Sandikcioglu, Özlem T1 - Effect of the Anchoring Layer and Transport Type on the Adsorption Kinetics of Lambda Carrageenan N2 - The kinetics of lambda carrageenan (λ-car) adsorption/desorption on/from anchoring layers under diffusion- and convection-controlled transport conditions were investigated. The eighth generation of poly(amidoamine) dendrimers and branched polyethyleneimine possessing different shapes and polydispersity indexes were used for anchoring layer formation. Dynamic light scattering, electrophoresis, streaming potential measurements, optical waveguide lightmode spectroscopy, and quartz crystal microbalance were applied to characterize the formation of mono- and bilayers. The unique combination of the employed techniques enabled detailed insights into the mechanism of the λ-car adsorption mainly controlled by electrostatic interactions. The results show that the macroion adsorption efficiency is strictly correlated with the value of the final zeta potentials of the anchoring layers, the transport type, and the initial bulk concentration of the macroions. The type of the macroion forming the anchoring layer had a minor impact on the kinetics of λ-car adsorption. Besides significance to basic science, the results presented in this paper can be used for the development of biocompatible and stable macroion multilayers of well-defined electrokinetic properties and structure. KW - AFM KW - Dynamic light scattering KW - Electrophoresis PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-540546 DO - https://doi.org/10.1021/acs.jpcb.1c03550 VL - 125 IS - 28 SP - 7797 EP - 7808 PB - American Chemical Society AN - OPUS4-54054 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Witt, Julia T1 - In situ Atomic Force Microscopy (AFM) studies of corrosion processes on thin film coated AA2024-T3 aluminium alloy surfaces N2 - The performance of functional coatings relies strongly on the stability of the polymer-metal interface. The increasing utilization of multi-material structures in the automotive and aerospace industry necessitates a fundamental understanding of the processes leading to interface degradation for the development of novel strategies to increase corrosion and delamination resistance. The aim of this project is to investigate the corrosion processes at the buried interface of thin film coated aluminium alloy AA2024-T3 under corrosive and coupled corrosive-mechanical load. A spin coating procedure was developed to synthesize epoxy-like coatings and their nanofiller loaded composites with controlled thickness by layer-by-layer deposition of poly[(o-cresyl glycidyl ether)-co-formaldehyde] and poly-(ethylenimine) bi-layers. Our results indicate that the incorporation of graphene into the epoxy-based coatings leads to the improvement of mechanical and barrier properties. Furthermore, the functional groups play important roles in the interfacial bonding between polymer matrix and the nanofillers. Atomic force microscopy (AFM) results indicate very homogeneous and dense films with a thickness of ~25 nm per bi-layer and the successful integration of the nanofillers into the composite coatings. Ellipsometry measurements of film thickness verified a proportional film growth with the number of deposited layers. The degradation and delamination behavior of the coating systems was characterized by means of in situ AFM corrosion experiments. Complementary energy dispersive X-ray spectroscopy (EDX) analysis was used to correlate the corrosion and delamination behavior with the different intermetallic particle chemistries and distributions. The presentation will summarize our results on the effect of coating composition and build-up on the local corrosion processes on thin film covered AA2024-T3 aluminium alloys. T2 - Eurocorr 2021 CY - Online meeting DA - 20.09.2021 KW - In situ AFM KW - Corrosion KW - Thin epoxy-based films PY - 2021 AN - OPUS4-54053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Advanced Characterization of the Surface Morphology and Chemistry within nano@BAM N2 - Both essential aspects of the surface of solid matter, its morphology and chemistry, are studied traditionally at BAM starting in the 60’s with different cyclical research focus areas, mostly related either to applicative research or method development. In the recent years, the focus has shifted almost exclusively to the nano-analytics of advanced materials such as complex nanoparticles, (ultra)thin films/coatings, nanocomposites, 2D materials, energy materials, etc. This is also the reason why BAM has established recently the new Competence Center nano@BAM (www.bam.de/Navigation/DE/Themen/Material/Nanotechnologie/sichere-nanomaterialien.html) with the five sub-fields nanoCharacterisation, nanoMaterial, nanoSafety, nanoData and nanoTechnology. The link to the BAM central guidelines to the safety in technology and chemistry is given by the development of reference products such as reference measurement procedures, reference (nano)materials, and newly reference data sets. Thus, an internationally well-networked group in surface analysis has been established @BAM, with regular contributions to integral analytical characterization with metrological and standardization background. Examples of newly developed methodical approaches will be given with an emphasis on correlative nano-analysis of morphology and chemistry of nanomaterials. Correlative imaging by STEM-in-SEM with high-resolution SEM and EDX, and further with AFM or the new technique TKD (Transmission Kikuchi Diffraction) will be explained on various examples of nanostructures, both as starting materials and embedded/functionalized nanoparticles in products. The unique analytical benefits of the Auger electron probe as a veritable nano-tool for surface chemistry will be highlighted. The panoply of advanced surface characterization methods @BAM is completed by discussing examples of hybrid analysis of the bulk of nanomaterials by X-ray Spectroscopy with the highest surface-sensitive methods X-ray Photoelectron Spectroscopy (XPS) and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS). Particularly for the analysis of the surface chemistry of nanostructures, such as the completeness of the shells of core-shell nanoparticles or in-depth and lateral gradients of chemistry within mesoporous thin layers, the latter methods are inherent. Other special developments like approaches for the quantitative determination of the roughness of particle surface by electron microscopy or for the quantitative determination of the porosity of thin mesoporous layers by electron probe microanalysis (EPMA) with SEM will be presented in conjunction with the corresponding advanced materials studied. Current research projects, promising ideas, including ongoing (pre-)standardization activities in the field of the challenging nano/surface analysis will be touched systematically, with the open goal of identifying future bilateral cooperation possibilities between EMPA and BAM. T2 - EMPA-Kolloquium CY - Online meeting DA - 01.12.2021 KW - Nanoparticles KW - Nano@BAM KW - Nanomaterials KW - Surface morphology and chemistry KW - Correlative analysis PY - 2021 AN - OPUS4-54039 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna A1 - Ciornii, Dmitri A1 - Hodoroaba, Vasile-Dan A1 - Braun, U. T1 - Requirements for inter-lab comparison studies and cooperation with CUSP and JRC N2 - Results from different methods applied to micro- and nanoplastics (MNPs) analysis show that there are large gaps in harmonisation with respect to terminology, size classes, sample preparation protocols and, finally, to the comparability of the measurands and descriptors. Within the European research cluster to understand the health impacts of micro- and nanoplastics (CUSP) working group WG3-Inter-Laboratory Comparisons an overview of the existing detection methods revealing advantages and disadvantages regarding the analytical tasks is being compiled. There is a clear need to develop high class characterized reference materials for MNPs in the size ranges of 100-10 µm and smaller than 10 µm, so that these can be used to validate methods and to make results comparable. Inter-laboratory comparisons (ILCs) on model samples with complex matrices regarding mass, or water samples for number-based methods, will help us to advance the process of harmonization as well as to train users early in process of developing new methods. We plan to keep all five CUSP projects well-connected also with the 'outside' MNP projects and ILCs and to extract the optimum of needs, capabilities, and efforts in order to launch new VAMAS ILCs which should expand already available ones. T2 - CUSP Meeting and General Assembly of PlasticsFatE CY - Online meeting DA - 13.12.2021 KW - CUSP KW - Microplastic KW - Inter-lab comparison KW - VAMAS KW - Reference materials PY - 2021 UR - https://cusp-research.eu/about/ AN - OPUS4-54036 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jlalia, I. A1 - Chabbah, T. A1 - Chatti, S. A1 - Schiets, F. A1 - Casabianca, H. A1 - Marestin, C. A1 - Mercier, R. A1 - Weidner, Steffen A1 - Kricheldorf, H. R. A1 - Errachid, A. A1 - Vulliet, E. A1 - Hammani, M. A1 - Jaffrezic-Renault, N. T1 - Alternating bio-based pyridinic copolymers modified with hydrophilic and hydrophobic spacers as sorbents of aromatic pollutants N2 - The main objective of this work was to design new advanced sorbent phases, alternating copolymers, derived from isosorbide and 2,6-difluorpyridine, to be used for the removal of aromatic organic pollutants present in water at low concentrations. Six different monomers, dianhydrohexitols isomers and bisphenol derivatives, weresynthesized in order to make it possible to study their hydrophilic and hydrophobiceffect on the sorption efficiency of the resulting polymeric phases. Before this study, we have confirmed the chemicals structures, molecular weights, and thermal properties of the obtained polymeric phases. Sorption results show a higher adsorption efficiency of P6 co-poly(ether-pyridine) based on bisphenol substituted with pyridineunits, for all tested pollutants, hydrophobic and hydrophilic ones, due to its less compact structure. Two aromatic organic pollutants, p-hydroxybenzoic acid and toluicacid, were selected as sorbates to study the adsorption characteristic, kinetics and isotherms of the copoly(ether pyridine) P6. Langmuir model led to a better fitting of the sorption isotherms; the sorption of toluic acid is easier than of that p-hydroxybenzoic acid. Comparing 1/n values for benzoic acid was two time lower for P6 compared to that for biochar and for crosslinked methacrylate resin, showing a higher efficiency KW - Alternating co-poly(ether pyridine)s KW - Aromatic organic compounds, KW - Biosourced isosorbide KW - Sorption isotherm KW - Sorption mechanism PY - 2021 DO - https://doi.org/10.1002/pat.5578 VL - 33 IS - 4 SP - 1057 EP - 1068 PB - Wiley Online Library AN - OPUS4-54031 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cakir, Cafer Tufan T1 - Unrevealing the depths of compositionally complex alloys with grazing exit XANES N2 - High entropy alloys (HEAs) are considered as a new class of alloys containing at least 5 elements with concentrations between 5 and 35 atomic percent. There has been a growing interest in HEAs in the material research field in recent years. Due to their adjustable composition, which enables the modifications of mechanical properties (such as hardness, strength and ductility etc) and their stability at high temperatures, HEAs have been the focus of various studies. Especially the corrosion behavior of HEAs has been a wide research interest. Since the grazing exit X-ray fluorescence (GEXRF) offers a non-destructive way to collect notable information regarding the high temperature oxidation, we consider it as a useful method to investigate how HEAs behave in corrosive environments. The main idea of grazing geometry is to enhance the fluorescence signal of the surface. This enables highly sensitive surface analyses of thin protective film on surface in sub-micrometer scale. Position-sensitive area detectors provide information regarding the signal emitted from the sample as a function of emission angle and thus allow depth-sensitive analysis. Furthermore, the data collected from samples of an incidence energy which lays within a specific energy range provides XANES data to determine oxidation states. Moreover, since GEXRF profiles can also be simulated through physical models (Urbach 1999), they enable us to determine the layer thickness of a given sample in a non-destructive way. In this contribution, we present the preliminary results of a conceptual study regarding layer properties of CrCoNi medium entropy alloy. The successful implementation of such methodological concept will pave the way for the investigation of more complex alloys with multiple layers, which is planned for the later phases of the project. T2 - XAFS 2021, The 18th International XAFS Conference CY - Online meeting DA - 02.08.2021 KW - GEXRF KW - High entropy alloys KW - XANES KW - Grazing exit KW - XAS PY - 2021 AN - OPUS4-54028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cakir, Cafer Tufan T1 - Unravelling the depths of complex alloys with grazing exit XANES N2 - High entropy alloys (HEAs) are considered as a new class of alloys containing at least 5 elements with concentrations between 5 and 35 atomic percent. There has been a growing interest in HEAs in the material research field in recent years. Due to their adjustable composition, which enables the modifications of mechanical properties (such as hardness, strength and ductility etc) and their stability at high temperatures, HEAs have been the focus of various studies. Especially the corrosion behavior of HEAs has been a wide research interest. Since the grazing exit X-ray fluorescence (GEXRF) offers a non-destructive way to collect notable information regarding the high temperature oxidation, we consider it as a useful method to investigate how HEAs behave in corrosive environments. The main idea of grazing geometry is to enhance the fluorescence signal of the surface. This enables highly sensitive surface analyses of thin protective film on surface in sub-micrometer scale. Position-sensitive area detectors provide information regarding the signal emitted from the sample as a function of emission angle and thus allow depth-sensitive analysis. Furthermore, the data collected from samples of an incidence energy which lays within a specific energy range provides XANES data to determine oxidation states. Moreover, since GEXRF profiles can also be simulated through physical models (Urbach 1999), they enable us to determine the layer thickness of a given sample in a non-destructive way. In this contribution, we present the preliminary results of a conceptual study regarding layer properties of CrCoNi medium entropy alloy. The successful implementation of such methodological concept will pave the way for the investigation of more complex alloys with multiple layers, which is planned for the later phases of the project. T2 - Denver X-Ray Conference DXC 2021 CY - Online meeting DA - 02.08.2021 KW - GEXRF KW - High entropy alloys KW - XANES KW - Grazing exit KW - XAS PY - 2021 AN - OPUS4-54027 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidner, Steffen A1 - Kricheldorf, H. R. T1 - SnOct2-catalyzed ROPs of L-lactide initiated by acidic OH- compounds: Switching from ROP to polycondensation and cyclization N2 - Ring-opening polymerizations (ROPs) of L-lactide are performed in bulk at 130°C with tin(II) 2-ethylhexanoate as catalyst and various phenols of differentacidity as initiators. Crystalline polylactides having phenyl ester end groups are isolated, which are almost free of cyclics. The dispersities and molecular weights are higher than those obtained from alcohol-initiated ROPs under identical conditions. Polymerizations at 160°C yield higher molecular weights than expected from the monomer/initiator ratio and a considerable fraction of cycles. The fraction of cycles increases with higher reactivity of the ester end group indicating that the cycles are formed by end-to-end cyclization. KW - Polylactide KW - MALDI-TOF MS KW - Polymerization PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-540250 DO - https://doi.org/10.1002/pol.20210823 SN - 2642-4150 VL - 60 IS - 5 SP - 785 EP - 793 PB - Wiley AN - OPUS4-54025 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yusenko, Kirill A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin T1 - Studies of high-entropy alloys using x-ray absorption fine structure at the bamline N2 - BAM line is multipurpose high-energy beamline. To extend studies of multicomponent alloys using EXAFS we perform own research and user experiments requiring multiedge spectroscopy, high-temperature and chemically aggressive sample environments. Our study of multicomponent alloys and high-entropy alloys open new perspectives in understanding their reactivity, corrosion, phase transformations and local ordering. T2 - SPP2006: large scale facilities CY - Online meeting DA - 02.11.2021 KW - Synchrotron studies KW - High-entropy alloys KW - EXAFS PY - 2021 AN - OPUS4-54016 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yusenko, Kirill A1 - Smekhova, A. A1 - Kuzmin, A. T1 - Extended X-Ray absorption fine structure (exafs) to study local constitution of high-entropy alloys N2 - Modern design of superior multi-functional alloys composed of several principal components requires in-depth studies of their local structure for developing desired macroscopic properties. Herein, peculiarities of atomic arrangements on the local scale and electronic states of constituent elements in the single-phase face-centered cubic (fcc)- and body-centered cubic (bcc)-structured high-entropy Alx-CrFeCoNi alloys (x = 0.3 and 3, respectively) are explored by element-specific X-ray absorption spectroscopy in hard and soft X-ray energy ranges. Simulations based on the reverse Monte Carlo approach allow to perform a simultaneous fit of extended X-ray absorption fine structure spectra recorded at K absorption edges of each 3d constituent and to reconstruct the local environment within the first coordination shells of absorbers with high precision. T2 - SPP2006: ordering in high-entropy alloys CY - Online meeting DA - 05.10.2021 KW - EXAFS KW - High-entropy alloys PY - 2021 AN - OPUS4-54015 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yusenko, Kirill A1 - Emmerling, Franziska A1 - de Oliveira Guilherme Buzanich, Ana T1 - X-Ray absorption spectroscopy to study multicomponent materials N2 - Detailed study of multicomponent systems in solid-state as well as in solution using X-ray diffraction and X-ray spectroscopy is one of the most common topics in modern materials chemistry. 5-6 component high-entropy alloys such as fcc- and bcc-structured AlxCoCrFeNi and fluorescent nanoparticles based on fluorite-structured SrF2 doped by rare-earth metals in organic solutions have high complexity and their local structure cannot be resolved using only diffraction. X-ray absorption spectroscopy should be applied to understand peculiarities in their local structure and make a link between structure on short and long ranges and their macroscopic properties. Here, based on two representativee examples, we discuss how a combination of several X-ray absorption edges might give new insights into complex materials. T2 - Virtual meeting of the African Light Source CY - Online meeting DA - 15.11.2021 KW - EXAFS KW - Synchrotron studies PY - 2021 AN - OPUS4-54014 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pauw, Brian Richard A1 - Smales, Glen Jacob T1 - What is in X-ray scattering Data? An overview of features. N2 - During the Better with Scattering 2021 workshop, we discuss what information can be obtained from an X-ray scattering pattern. Examples of structural features and their physical expression in scattering patterns are demonstrated. T2 - Better with Scattering workshop 2021 CY - Online meeting DA - 29.11.2021 KW - Scattering KW - SAXS KW - X-ray scattering KW - Data analysis KW - Data interpretation KW - Fourier transforms PY - 2021 AN - OPUS4-54011 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Serebrennikova, P. A1 - Komarov, V. A1 - Sukhikh, A. A1 - Khranenko, S. A1 - Zadesenetz, A. A1 - Gromilov, S A1 - Yusenko, Kirill T1 - [NiEn3](MoO4)0.5(WO4)0.5 co-crystals as single-source precursors for ternary refractory Ni-Mo-W alloys N2 - The co-crystallisation of [NiEn3](NO3)2 (En = ethylenediamine) with Na2MoO4 and Na2WO4 from a water solution results in the formation of [NiEn3](MoO4)0.5(WO4)0.5 co-crystals. According to the X-ray diffraction analysis of eight single crystals, the parameters of the hexagonal unit cell (space group P–31c, Z = 2) vary in the following intervals: a = 9.2332(3)–9.2566(6); c = 9.9512(12)–9.9753(7) Å with the Mo/W ratio changing from 0.513(3)/0.487(3) to 0.078(4)/0.895(9). The thermal decomposition of [NiEn3](MoO4)0.5(WO4)0.5 individual crystals obtained by co-crystallisation was performed in He and H2 atmospheres. The ex situ X-ray study of thermal decomposition products shows the formation of nanocrystalline refractory alloys and carbide composites containing ternary Ni–Mo–W phases. The formation of carbon–nitride phases at certain stages of heating up to 1000 °C were shown. KW - Single source precursors KW - Phase diagrams PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-540123 DO - https://doi.org/10.3390/nano11123272 VL - 11 IS - 12 SP - 1 EP - 12 PB - MDPI CY - Basel AN - OPUS4-54012 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Asanova, T.I. A1 - Asanov, Igor A1 - Yusenko, Kirill A1 - Le Fontane, Camille A1 - Gerasimov, E.Y. A1 - Zadesenetz, A.V. A1 - Korenev, S.V. T1 - Time-resolved study of Pd-Os and Pt-Os nanoalloys formation through thermal decomposition of Pd(NH3)(4) OsCl6 and Pt(NH3)(4) OsCl6 complex salts N2 - The formation mechanisms of Pd-Os and Pt-Os alloys in the course of thermal decomposition of iso-formular and isostructural complex salts [Pd(NH3)4][OsCl6] and [Pt(NH3)4][OsCl6] in an inert atmosphere have been studied by in-situ QXAFS, XPS and PXRD. The mechanisms of thermal decomposition of the precursors are found to differ from each other, but the detected intermediate products show no significant effect on the local atomic structure around Os, Pt/Pd in their final products. A crystalline beta-trans-[Pd(NH3)2Cl2] intermediate of the first step of thermal decomposition of [Pd(NH3)4][OsCl6] makes the anion [OsCl6]2− transform differently than that of [Pt(NH3)4][OsCl6]. It transforms into a short-lived [Os(NH3)xCl6-x] (2≤x≤4), and then to a distorted octahedron [OsCl6]2−, similar to the high-temperature modification of OsCl4. In case of [Pt(NH3)4][OsCl6], the intermediate [Os(NH3)2Cl4] modifies into four chlorine coordinated Os,{OsCl4}0/1−. Consecutive reduction of Pd(II)/Pt(II) and Os(IV) to the metals defines the homophilic atomic order with the fcc-Pd covered by a random Pd-Os alloy layer and Os on the surface, that is supported by High-Resolution Transmission Electron Mictroscopy (HRTEM) and Scanning TEM (STEM) energy dispersive X-ray (EDX) data, and the diffusion direction going from the surface (hcp-Os) to bulk (fcc-Pd/Pt). As a result, the heterogeneous alloys are formed with a very similar electronic and local atomic structure of Os and Pd/Pt. Upon alloying, the Os 5d5/2,3/2 and Pt 5d5/2,3/2 levels are depleted in the Pt-Os alloys compared to dispersed hcp-Os, fcc-Pt, and Pt foil. This is an unusual behaviour for Os and Pt, calling into question the versatility of d-band theory in bimetallic Os-alloys. The spin-orbit effect at the Os site has been found for both the Pd-Os and Pt-Os alloys, but it is about 4 times less compared to the complex salts. The obtained values for the complex compounds are comparable with those for the iridates, proposed as materials with spin-orbit-induced properties. KW - Thermal decomposition KW - Quick-EXAFS PY - 2021 DO - https://doi.org/10.1016/j.materresbull.2021.111511 VL - 144 SP - 111511 PB - Elsevier Ltd. AN - OPUS4-54010 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fedorova, E.A. A1 - Asanov, Igor A1 - Yusenko, Kirill A1 - Asanova, T.I. A1 - La Fontaine, Camille A1 - Roudenko, olga A1 - Gerasimov, E.Y. A1 - Vasilchenko, D A1 - Korenev, S.V. T1 - Time-resolved study of thermal decomposition process of (NH4)(2) PtCl6 : Intermediates and Pt nucleation N2 - Evolution in crystal, electronic and local atomic structures of Pt in ammonium hexachloroplatinate in the course of thermal decomposition in inert and reducing atmospheres have been studied by Powder X-Ray Diffraction (PXRD) and Quick X-ray Absorption Fine Structure (QXAFS) at Pt L3-edge for deeper understanding the thermally-induced solid state reaction and the formation of metallic nanoparticles. A three-step thermal decomposition mechanism of (NH4)2[PtCl6] in the inert atmosphere with the intermediate products Pt(NH3)2Cl2 and PtCl2 has been found instead one-[G.Meyer, A.Möller, J. Less. Common. Met. 170 (1991) 327–331] and two-step one [Q.Kong, F.Baudelet, J.Han, S.Chagnot, L.Barthe, J.Headspith, R. Goldsbrough, F.E.Picca, O.Spalla, Sci. Rep. 2 (2012) 1018–1025] considered early. In the reducing atmosphere, the thermal decomposition is a two-step process with the formation of the intermediate PtCl2. The best approach to determining the number of thermal decomposition steps turned out to be the express-analysis of QXAFS spectra offered in the papers, based on the simultaneous presentation of the most important parameters extracted from X-ray Absorption Near Edge Structure (XANES) and Fourier transformed Extended XAFS (EXAFS). This express-analysis was tested by comparison with results of various approaches such as conventional EXAFS fitting, linear combination fit (LCF), Multivariate Curve Resolution Alternating Least Squares method (MCR ALS). KW - Platinum KW - Quick-EXAFS PY - 2021 DO - https://doi.org/10.1016/j.vacuum.2021.110590 VL - 194 SP - 110590 PB - Elsevier AN - OPUS4-54008 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Joubert, J.M. A1 - Crivello, J.C. A1 - Yusenko, Kirill T1 - Modification of Lu's (2005) high pressure model for improved high pressure/high temperature extrapolations. Part II: Modeling of osmium-platinum system at high pressure/high temperature N2 - In Part I of this paper, we have described a modification brought to the model of Lu (X.-G. Lu et al., Comput. Coupling Phase Diagr. Thermochem. 29 (2005) 49–55) in order to avoid extrapolation problems at high pressure and temperature. We now extend this approach to the study of a binary system: Os–Pt. For this, a complete description (equation of state) of Os at high pressure/high temperature is provided including the liquid phase. The thermodynamic assessment of the system Os–Pt has been carried out at ambient pressure by the Calphad method. All this study has been supported by first principles, special quasi-random structure (including under high pressure) and phonon calculations. Finally, using the high pressure description of metastable structures (hcp Pt and fcc Os), we have been able to obtain by extrapolation a complete description of Os–Pt system up to 500 GPa. Recent experimental data for Os–Pt system obtained up to 50 GPa at various temperatures up to 2300 °C may us allow to validate our modeling approach. KW - Phase diagrams KW - High-pressure PY - 2021 DO - https://doi.org/10.1016/j.calphad.2021.102311 VL - 74 SP - 102311 PB - Elsevier AN - OPUS4-54005 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yusenko, Kirill A1 - Kabelitz, Anke A1 - Schokel, Alexander A1 - Wagner, Ralf A1 - Prinz, Carsten A1 - Kemnitz, E A1 - Emmerling, Franziska A1 - Krahl, Thoralf A1 - de Oliveira Guilherme Buzanich, Ana T1 - Local Structure of Europium-Doped Luminescent Strontium Fluoride Nanoparticles: Comparative X-ray Absorption Spectroscopy and Diffraction Study N2 - Rare-earth based luminescent materials are key functional components for the rational design of light-conversion smart devices. Stable Eu3+-doped strontium fluoride (SrF2) nanoparticles were prepared at room temperature in ethylene glycol. Their luminescence depends on the Eu content and changes after heat treatment. The crystallinity of heat-treated material increases in comparison with as-synthesized samples. Particles were investigated in solution using X-ray diffraction, small-angle X-ray scattering, and X-ray spectroscopy. After heat treatment, the size of the disordered nanoparticles increases together with a change of their local structure. Interstitial fluoride ions can be localized near Eu3+ ions. Therefore, non-radiative relaxation from other mechanisms is decreased. Knowledge about the cation distribution is key information for understanding the luminescence properties of any material. KW - SrF2 KW - EXAFS KW - Eu PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-540094 DO - https://doi.org/10.1002/cnma.202100281 VL - 7 IS - 11 SP - 1221 EP - 1229 PB - Wiley Online Library AN - OPUS4-54009 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meurer, Maren A1 - Arb, Hannes A1 - Altmann, Korinna T1 - Optimierung der Mikroplastik Analytik mittels TED-GC/MS sowie Reduktion von falsch positiven PE Werten durch beschleunigtes Lösemittelverfahren N2 - Ein drastisch hoher Polyethylene Massenanteil wurde bei der Analytik der Umweltproben im Vergleich zu weiteren Polymeren festgestellt. Zu einem Überbefund des Polyethylene können strukturell verwandte Verbindungen wie z.B. Fette durch Signalüberlagerung führen. Mithilfe von beschleunigter Lösemittelextraktion soll die störende Komponente entfernt werden. T2 - Die Wasser 2021 CY - Online meeting DA - 10.05.2021 KW - Extraktion KW - Mikroplastik KW - ASE KW - Polyethylene PY - 2021 AN - OPUS4-53896 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Griepentrog, Michael A1 - Hertwig, Andreas A1 - Hielscher-Hofinger, Stefan A1 - Weise, Matthias T1 - Functional coatings for mechanical applications: characterization and standardization N2 - The paper addresses the “Functional coatings for mechanical applications: characterization and standardization” and the following points are discussed in more detail: 1. Mechanic alapplications (coatings for tools and components, system features vs. material parameters) 2. Mechanical characterization (instrumented indentation testing (IIT), centrifugal adhesion testing (CAT), state of standardization) 3. Topometric characterization (white light interference microscopy (WLIM, 3D), mechanical stylus (MS, 2D), state of standardization) 4. Optical characterization (spectroscopic ellipsometry (SE), inter-laboratory comparison, state of standardization) T2 - IC-CMTP6 CY - Miskolc, Hungary DA - 04.10.2021 KW - Spectroscopic Ellipsometry KW - White Light Interference Microscopy KW - Instrumented Indentation Testing KW - Functional coatings KW - Mechanical characterization KW - Optical characterization KW - Topometric characterization KW - Standardization PY - 2021 AN - OPUS4-53987 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Griepentrog, Michael A1 - Hertwig, Andreas A1 - Hielscher-Hofinger, Stefan A1 - Lange, Thorid A1 - Weise, Matthias T1 - Uncertainty budgets in surface technology: stepheigt, layerthickness, indentation hardness, adehesive strength N2 - The object (sample) and the measurement/testing procedure may always have unknown degrees of freedom, i.e. instead of 𝐯 ≥ n – 1 in many cases 𝐯 ≫ n - 1 may apply, in particular in the micro- and nano-world! T2 - 10. VDI-Fachtagung, Messunsicherheit und Prüfprozesse CY - Erfurt, Germany DA - 10.11.2021 KW - Methodology in metrology KW - Methodology in testing KW - Spectroscopic Ellipsometry KW - Instrumented Indentation Testing (IIT) KW - Centrifugal Adhesion Testing (CAT) PY - 2021 AN - OPUS4-53986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska T1 - Shaken not stirred: in situ investigations of mechanochemical processes N2 - Mechanochemistry has emerged as one of the most interesting synthetic protocols to produce new materials. The development of mechanochemistry as a synthetic method is supported by excellent research by many groups worldwide in a wide range of applications. The potential of mechanochemistry is also reflected in the inclusion in IUPAC’s 10 chemical innovations that will change our world’.[1] Solvent-free methodologies lead to unique chemical processes during synthesis with the consequent formation of martials with new properties.2 In this contribution, we will discuss our recent results investigating the formation of (polymorphic) cocrystals, coordination polymers, metal oxides and metal nanoparticles.[3-8] We introduced different setups enabling in situ investigation of mechanochemical reactions using synchrotron XRD combined with Raman spectroscopy and thermography. T2 - Deutsche Kristallzüchtertagung CY - Berlin, Germany DA - 06.10.2021 KW - Mechanochemistry KW - In situ real-time monitoring KW - Crystal PY - 2021 AN - OPUS4-53996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska T1 - Shaken not stirred: enhancing the flavor of mechanochemistry N2 - Mechanochemistry is increasingly used for synthesizing soft matter materials including metal organic compounds and cocrystals.1 The ever-increasing interest in this method is contrasted by a limited mechanistic understanding of the mechanochemical reactivity and selectivity. Time-resolved in situ investigations of milling reactions provide direct insights in the underlying mechanisms.2-4 We recently introduced different setups enabling in situ investigation of mechanochemical reactions using synchrotron XRD combined with Raman spectroscopy and thermography. The presented setup allows the detection of crystalline, amorphous, eutectic, and liquid intermediates. Furthermore, the chemical composition of the reaction mixture was found to be directly correlated with changes in the temperature profile of the reaction. The resulting deeper kinetic and thermodynamic understanding of milling processes is the key for future optimization of mechanochemical syntheses. In this contribution, we will discuss our recent results investigating the formation of (polymorphic) cocrystals and coordination polymers.2,3,5 Our results indicate that in situ investigation of milling reactions offer a new approach to tune and optimize mechanochemical syntheses. T2 - BCA/BACG joint spring meeting CY - Online meeting DA - 29.03.2021 KW - Mechanochemistry KW - Cocrystals KW - Crystal Engineering PY - 2021 AN - OPUS4-53995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska T1 - Scientific Writing - best practice tools N2 - Personal view of an experienced writer on how to write a paper. T2 - MatchingCamp 2021 CY - Bad Belzig, Germany DA - 08.11.2021 KW - Writing PY - 2021 AN - OPUS4-53999 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 - Sachse, René A1 - Moor, Maëlle A1 - Kraehnert, Ralph A1 - Hodoroaba, Vasile-Dan A1 - Hertwig, Andreas T1 - Ellipsometry-based approach for the characterization of mesoporous thin films for H2 technologies N2 - Porous thin layer materials are gaining importance in different fields of technology and pose a challenge to the accurate determination of materials properties important for their function. In this work, we demonstrate a hybrid measurement technique using ellipsometry together with other independent methods for validation. Ellipsometry provides information about the porosity of different mesoporous films (PtRuNP/OMC = 45%; IrOx = 46%) as well as about the pore size (pore radius of ca. 5 nm for PtRuNP/OMC). In addition, the electronic structure of a material, such as intraband transitions of a mesoporous IrOx film, can be identified, which can be used to better understand the mechanisms of chemical processes. In addition, we show that ellipsometry can be used as a scalable imaging and visualization method for quality assurance in production. These require accurate and traceable measurements, with reference materials playing an important role that include porosity and other related properties. We show that our novel analytical methods are useful for improving analytical work in this entire field. KW - Porous materials KW - Electrolysis KW - Spectroscopic ellipsometry KW - Hybrid metrology measurement KW - Electron microscopy PY - 2021 DO - https://doi.org/10.1002/adem.202101320 SP - 1 EP - 17 PB - Wiley-VCH AN - OPUS4-53960 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reetz, U. A1 - Beck, Uwe A1 - Hielscher-Hofinger, Stefan A1 - Lerche, D. T1 - CAT -Technologie (CentrifugalAdhesionTesting) im Standardisierungsprozess N2 - Der DIN Ringversuch weist nach, dass die CAT Technologie zur ZPM Prüfung statistisch nicht unterscheidbare Prüfergebnisse liefert, so dass lediglich eine Ergänzung der DIN EN 15870 unter Berücksichtigung der CAT-Technologie (mit Bezug auf äquivalente Kraft und Weg zunahmen) als zweiter normativer Prüfmethode sinnvoll erscheint. Vorstellung des Revisionsvorschlages im CEN TC 193 am 08.04.2021 mit dem Beschluss, eine Umfrage unter Verwendung des unveränderten deutschen Revisionsvorschlages durchzuführen. T2 - SKZ-Expertenkreis „Kleben und Oberflächentechnik für Kunststoffe“ 2021 CY - Online meeting DA - 22.09.2021 KW - Centrifugal Adhesion Testing (CAT) KW - Zweistichproben t Test: (ZPM) KW - Ringversuch KW - Validierung KW - DIN EN 15870 PY - 2021 AN - OPUS4-53964 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Katsikini, M. A1 - Filintoglou, K. A1 - Pinakidou, F. A1 - Pilatsikas, N. A1 - Arvanitidis, J. A1 - Christofilos, D. A1 - Paloura, E.C. A1 - Ves, S. A1 - Reinholz, Uwe A1 - Papadomanolaki, E. A1 - Lliopoulos, E. T1 - Scaling of phonon frequencies and electron binding energies with interatomic distances in InxGa1−xN N2 - In-K-edge x-ray absorption fine structure (EXAFS), x-ray photoelectron, and Raman spectroscopy results are combined for a comprehensive study of InxGa1−xN layers with energy gaps extending over nearly the whole visible spectrum. The In–N and In–(In,Ga) distances determind by EXAFS are used for the derivation of the In–N bond ionicity as well as for the phonon frequency dependence of the LO and B21 modes, assessed by Raman, and the N 1s, In 3d5/2, Ga 3s, and Ga 2p1/2 electron binding energies on those distances. Phonon confinement due to perturbation of the periodic potential caused by the alloying is also quantified. KW - Band gap KW - Phonons KW - Epitaxy KW - Electronic structure KW - X-ray photoelectron KW - Nitrides PY - 2021 DO - https://doi.org/10.1063/5.0069359 VL - 130 IS - 20 SP - 205706 - 1 EP - 205706 - 9 PB - AIP Publishing AN - OPUS4-53956 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tache, O. A1 - Durand, B. A1 - Barruet, E. A1 - Gobeaux, F. A1 - Pauw, Brian Richard A1 - Thill, A. T1 - Synthesis of SiO2 Nanoparticles as reference materials: Metrological measurements and in-situ kinetics in lab with Small Angle X-Ray Scattering N2 - The unambiguous correlation of possible health and sustainability risks to nanoparticle size must be enabled by reliable measurement of nanoparticle size, to ensure comparability and compatibility between results measured under different methods. The NPSIZE project funded by European Metrology Program (EMPIR) develop methods, reference materials and modelling to improve the traceability chain, comparability and compatibility of nanoparticle size measurements. In this work, we present how spherical silica nanoparticles are synthetized with controlled monomodal or bimodal dispersion to be use as reference materials and international round-robin. Improving the fabrication requires a fine understanding of synthesis (1), coupled with an expertise of in-situ or ex-situ analysis methods. This is a new challenge for the analysis : determining not only average characteristics (size, chemical composition and shape ...) but also the concentration and the distribution over the population studied (2). Small-Angle X-ray Scattering (3) allows very precise measurements of the nanoparticles size and concentration that can be directly link to the metric system (4) (metrological traceability) . We developed a SAXS laboratory instrument dedicated to the in-situ characterization of nanoparticles, which enable fast measurements, and the monitoring of the synthesis parameters. Measurement protocols and software processing chain (5) (i.e. size distribution) are also combined & optimized. T2 - CNANO2021 CY - Toulouse, France DA - 25.11.2021 KW - X-ray scattering KW - Silica particles KW - Synthesis KW - Reference materials PY - 2021 DO - https://doi.org/10.5281/zenodo.5749256 AN - OPUS4-53931 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reetz, U. A1 - Lerche, D. A1 - Hielscher-Hofinger, Stefan A1 - Kubitzki, Jan A1 - Beck, Uwe T1 - Load- and path-controlled determination of bonding strength of butt joints - Comparison between tensile testing machine and centrifuge technology N2 - The round robin test proves that the CAT-Technology provides statistically indistinguishable test results compared to TTM. A supplement to DIN EN 15870 taking into account CAT-Technology (with reference to equivalent increases of load and displacement) as second normative test method appears to make sense. A presentation of a revision proposal at CEN TC 193 has been introduced with the decision to conduct a survey using the unchanged German revision proposal. T2 - EURADH 2021 - 13 th European Adhesion Conference CY - Online meeting DA - 11.10.2021 KW - CAT – Technology KW - Tensile testing machine (TTM) KW - Round robin test KW - Validation PY - 2021 AN - OPUS4-53948 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 - CONF A1 - Schönhals, Andreas T1 - Thermal behavior of high preformance polymers - Fast Scanning Calorimetry and more N2 - The glass tranistion behavior of polymers of intrinsic microporosity and polynornornes is discussed. T2 - Flash DSC Conference 2021 CY - Online meeting DA - 06.12.2021 KW - Polymer of Intrisic Maicroporosity KW - Highly permeable polynorbornenes PY - 2021 AN - OPUS4-53938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin T1 - Importance of Radiation Damage to DNA-Protein Complexes N2 - The formation of DNA-protein complexes ocurrs during replication and repair within cells. They are assumed to modify the damage caused by ionization radiation during radaition therapy. Hereby the assumption is, that the underlying damaging channels in DNA and proteins are modified, especially when compared to single molecules. T2 - Scientific online presentations workshop CY - Online meeting DA - 03.12.2021 KW - DNA KW - Proteins KW - Radiation damage KW - Ionizing radiation KW - Hydroxyl radicals PY - 2021 AN - OPUS4-53894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sachse, René A1 - Pflüger, Mika A1 - Velasco-Vélez, Juan-Jesús A1 - Sahre, Mario A1 - Radnik, Jörg A1 - Bernicke, Michael A1 - Bernsmeier, Denis A1 - Hodoroaba, Vasile-Dan A1 - Krumrey, Michael A1 - Strasser, Peter A1 - Kraehnert, Ralph A1 - Hertwig, Andreas T1 - Operando electrochemical spectroscopic ellipsometry: Material properties of highly active mesoporous IrOx films revealed under realistic OER conditions N2 - Hydrogen production via water electrolysis will be an essential cornerstone in development of sustainable, fossil-free fuel and chemical production on a global scale. The activity and stability of each catalyst is highly dependent on the properties of the coating, i.e., phase composition, crystallinity, accessible surface area, and many other factors. The key to developing improved catalysts is a better understanding of the relationships between their performance, stability, and physicochemical properties. However, these relationships can be complex and are also strongly influenced by the reaction environment. Therefore, operando analysis of the catalyst material during catalysis at realistic potentials and current densities is highly desirable. However, many analytical techniques cannot be applied in liquid environments at realistic potentials and current densities. We propose environmental ellipsometric analysis in a dedicated electrochemical flow cell as a method to evaluate gas evolution reactions operando under realistic working conditions. Figure 1 illustrates schematically the developed technique. Key factors to success are highly active model-type catalysts, a suitable sample environment, and a deep understanding of the appropriate model development, as well as concise cross validation with numerous other analytical techniques. The method was developed and validated by analyzing a calcination series (300 – 600 °C) of mesoporous templated IrOx films ex-situ and operando under oxygen evolution reaction (OER) conditions. The employed environmental electrochemical spectroscopic ellipsometric (ECSE) analysis revealed during OER the change of optical and electronic properties, i.e. the dielectric functions, resistivity and band-to-band transitions (p-d band transitions). Film thickness and porosity were validated by means of scanning electron microscopy (SEM), X-ray reflectometry (XRR) or ellipsometric porosimetry (EP), electrical and electronic properties by means of conductivity measurements, X-ray photoelectron spectroscopy (XPS) or UV-Vis-NIR absorption spectroscopy. The electronic structures of the catalysts from valence electron energy loss spectra (VEELS) derived from ε1 and ε2 from SE measurements reveal a direct correlation with electrochemical activities in OER. In the presentation reversible and irreversible potential-dependent changes of the catalyst properties during operation will be discussed along with the dynamics of gas formation, transport and dissolution at different potentials. T2 - 11th Workshop Ellipsometry (WSE 11) CY - Steyr, Austria DA - 06.09.2021 KW - Ectrocatalysis KW - Mesoporous iridium oxide films KW - Non-destructive operando analysis KW - Oxygen evolution reaction KW - Spectroscopic ellipsometry PY - 2021 AN - OPUS4-53915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feiler, Torvid A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A1 - Rhim, S.-Y. A1 - Schröder, V. A1 - List-Kratochvil, E. A1 - Emmerling, Franziska T1 - Mechanically flexible crystals: materials for new generation of responsive materials N2 - Based on the nature of the deformation, molecular crystals can be defined as being plastically (irreversible) or elastically (reversible)bendable. The mechanical response of crystals is thereby directly related to they structure.The structural elements required for a specific mechanical behavior are known, so that compounds with these properties can be synthesized by applying the rules of crystal engineering. T2 - Berlin Science Week CY - Berlin, Germany DA - 01.11.2021 KW - Flexible crystals PY - 2021 AN - OPUS4-53907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feiler, Torvid A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A1 - Rhim, S.-Y. A1 - Schröder, V. A1 - List-Kratochvil, E. A1 - Emmerling, Franziska T1 - Optimierung der mechanischen Eigenschaften eines organischen Kristalles durch Polymorphismus für die Anwendung als flexibler Waveguide N2 - Kristalle sind in der Regel spröde und neigen dazu, bei mechanischer Belastung zu brechen. Dieses Verhalten schränkt ihre Anwendungsmöglichkeiten stark ein. Durch die Entdeckung von mechanischer Flexibilität in Kristallen wurde dieses Problem gelöst. Je nach Art der Verformung können Kristalle in plastisch (irreversibel) oder elastisch (reversibel) biegbar unterteilt werden. Die Verbindung 4-Brom-6-[(6-chlorpyridin-2-ylimino)methyl]phenol (BCMPMP) ist ein vielversprechender Kandidat für die Anwendung als flexibler Waveguide. BCMPMP hat zwei verschiedene Polymorphe mit unterschiedlichen optischen und mechanischen Eigenschaften. Die spröden Kristalle der Form I zeigen eine sehr schwache Emission bei 605 nm (λex = 425 nm; Photolumineszenz-Quantenausbeute Φ = 0,4 %). Im Gegensatz dazu zeigt die plastische Form II eine starke Emission bei 585 nm (λex = 425 nm; Φ = 8,7 %). Aufgrund der mechanischen Flexibilität wurde die Eignung der Form II als Waveguide untersucht. T2 - Tag der Chemie 2021 CY - Online meeting DA - 06.07.2021 KW - Flexible crystals KW - Polymorphism KW - Waveguide PY - 2021 AN - OPUS4-53908 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feiler, Torvid A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A1 - Rhim, S.-Y. A1 - Schröder, V. A1 - List-Kratochvil, E. A1 - Emmerling, Franziska T1 - Polymorphic tuning of a flexible organic crystal optical waveguide N2 - Crystalline molecular materials are usually brittle and are prone to break upon external mechanical force. This fragility poses challenges for their application in next-generation technologies, including sensors, synthetic tissues, and advanced opto-electronics. The recent discovery of mechanical flexibility in single crystals of molecular materials has solved this problem and enable the design of smart flexible device technologies. Mechanical flexibility of organic crystals can be tuned by altering the weak interactions in the crystal structure, for examples through polymorphism. Here we report 4-bromo-6-[(6-chlorolpyridin-2-ylimino)methyl]phenol (BCMPMP) as a promising candidate for future waveguide technologies. It turns out that BCMPMP has two different polymorphs with distinct optical and mechanical properties. Form I shows brittle behavior under mechanical stress and exhibits very weak emission at 605 nm (λex = 425 nm) together with a low fluorescence quantum yield (Φ = 0.4 %).In contrast, Form II has a large plastic (irreversible bending) regime and a bright emission at 585 nm (λex = 425 nm; Φ = 8.7 %). Making use of favorable mechanical fexiblity and optical properties, form II was explored as a bendable optical waveguide. Light was successfully propagated through a straight-shaped and mechanically deformed BCMPMP crystal. Depending on the light source, active or passive waveguiding could be achieved. So BCMPMP can also be used as a flexible wavelength filter. T2 - Congress of the International Union of Crystallography - IUCr 2021 CY - Online meeting DA - 14.08.2021 KW - Flexible crystals KW - Polymorphism KW - Waveguide PY - 2021 AN - OPUS4-53906 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feiler, Torvid A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A1 - Rhim, S.-Y. A1 - Schröder, V. A1 - List-Kratochvil, E. A1 - Emmerling, Franziska T1 - Tuning the mechanical flexibility of organic molecular crystal by polymorphism for flexible optical waveguide N2 - Crystalline molecular materials are usually brittle and are prone to break into pieces upon external mechanical force. This fragility poses challenges for their application in next-generation technologies, including sensors, synthetic tissues, and advanced opto-electronics. The recent discovery of mechanical flexibility in single crystals of molecular materials has solved this issue and enable the design of smart flexible device technologies. Plastic crystals can be deformed permanently. This behavior is based on anisotropic molecular arrangements and the existence of facile slip planes which allow a permanent motion within the lattice. In contrast, elastic crystals can be deformed, but regain the original structure when the force is removed. This phenomenon is related to energetically isotropic molecular packing. Here we report 4-bromo-6-[(6-chlorolpyridin-2-ylimino)methyl]phenol (BCMPMP) as a promising candidate for future waveguide technologies. It turns out that BCMPMP has two different polymorphs with distinct optical and mechanical properties. Form I crystallizes in the orthorhombic space group Pca21 and shows brittle behavior. This structure exhibit very weak emission at 605 nm (λex = 425 nm) together with a low fluorescence quantum yield (Φ = 0.4 %). On the other hand, form II (monoclinic space group P21/c) has a large plastic regime and a bright emission at 585 nm (λex = 425 nm; Φ = 8.7 %). Based on its improved mechanical and optical properties, form II was explored as a bendable optical waveguide. Light was successfully propagated through a straight-shaped and mechanically deformed BCMPMP crystal. Depending on the light source, active or passive waveguiding could be achieved. So BCMPMP can also be used as a flexible wavelength filter. T2 - International School of Crystallography in Erice CY - Online meeting DA - 30.05.2021 KW - Flexible crystals KW - Polymorphism KW - Waveguide PY - 2021 AN - OPUS4-53905 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Feiler, Torvid A1 - Michalchuk, Adam A1 - Schröder, V. A1 - List-Kratochvil, E. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit T1 - Elastic Flexibility in an Optically Active Naphthalidenimine-Based Single Crystal N2 - Organic single crystals that combine mechanical flexibility and optical properties are important for developing flexible optical devices, but examples of such crystals remain scarce. Both mechanical flexibility and optical activity depend on the underlying crystal packing and the nature of the intermolecular interactions present in the solid state. Hence, both properties can be expected to be tunable by small chemical modifications to the organic molecule. By incorporating a chlorine atom, a reportedly mechanically flexible crystal of (E)-1-(4-bromo-phenyl)iminomethyl-2-hydroxylnaphthalene (BPIN) produces (E)-1-(4-bromo-2-chloro-phenyl)iminomethyl-2-hydroxyl-naphthalene (BCPIN). BCPIN crystals show elastic bending similar to BPIN upon mechanical stress, but exhibit a remarkable difference in their optical properties as a result of the chemical modification to the backbone of the organic molecule. This work thus demonstrates that the optical properties and mechanical flexibility of molecular materials can, in principle, be tuned independently. KW - Elastic Crystal PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539040 DO - https://doi.org/10.3390/cryst11111397 VL - 11 IS - 11 SP - 1397 PB - MDPI AN - OPUS4-53904 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Halder, A. A1 - Maiti, A. A1 - Dinda, S. A1 - Bhattacharya, Biswajit A1 - Ghoshal, D. T1 - Unraveling the Role of Structural Dynamism in Metal Organic Frameworks (MOF) for Excited-State Intramolecular Proton Transfer (ESIPT) Driven Water Sensing N2 - Ligand based modification has been performed to synthesize a pair of mixed ligands d10 MOF based materials related to a previously published compound as a base material. The previous compound was a Zn(II)-MOF, {[Zn(4-bpdh)(H2dht)](MeOH)(H2O)}n (1) [N,N′-bis(1-pyridin-4-yl-ethylidene)hydrazine = 4-bpdh and 2,5-dihydroxyterephthalic acid = H4dht], which is a five-fold interpenetrated framework and highly dynamic in nature. In the first synthetic modification, the central metal is replaced by Cd(II), which has the same framework formula as the base material, but this is a rigid compound and also there is no interpenetration in the framework. In the second modification, along with the metal center, the 4,4′- coordinating N,N′-donor ligand is replaced by an isomeric 3,3′-coordinating N,N′- donor linker. In this compound, the dynamism is regenerated. The dynamic nature can be realized by the extensive PXRD studies and characteristic “step-shaped” gas/solvent adsorption behavior for CO2, water, and ethanol. Furthermore, all these 3D MOFs show excited-state intramolecular proton transfer phenomena and water sensing properties in different organic solvents. Here excitingly, the ease of water sensing property is directly related to the dynamic behavior of the framework which has been studied thoroughly in terms of structural correlation. KW - MOFs PY - 2021 DO - https://doi.org/10.1021/acs.cgd.1c00446 SN - 1528-7483 VL - 21 IS - 11 SP - 6110 EP - 6118 PB - ACS Publications AN - OPUS4-53903 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna T1 - Mikroplastik Referenzmaterial und erste Vergleichsuntersuchungen N2 - Hierbei geht es um die Vorstellung von ersten Möglichkeiten um Referenzmaterial für die Mikroplastik-Analytik herzustellen und die Ergebnisse erster Vergleichsversuche. T2 - EUROLAB-D Workshop: Mikroplastik in der Praxis CY - Online meeting DA - 30.11.2021 KW - Mikroplastik KW - Referenzmaterial KW - Vergleichsversuche PY - 2021 AN - OPUS4-53880 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - EMPIR nPSize - Improved Traceability Chain of Nanoparticle Size Measurement N2 - In order to assess new nanomaterials and nanoparticles for potential risks to health and the environment, they need to be well-characterised. The measurement of constituent nanoparticle size, shape, and size distribution are important factors for the risk evaluation process. EMPIR project Improved traceability chain of nanoparticle size measurements (17NRM04, nPSize) is working to assess a range of traceable nanoparticle measurement approaches, including Electron Microscopy (SEM, TEM, STEM-in-SEM), Atomic Force Microscopy and Small Angle X-ray Scattering, and deliver improved calibration methods to users. For the techniques under investigation, physical models of their response to a range of nanoparticle types are developed. Validated reference materials are also used for inter-comparisons of measurement systems, with an evaluation of the associated measurement uncertainty. With project contributions to standards development work, manufacturers will be better placed to assess the human and environmental risks posed by nanomaterials across a whole range of products. T2 - EMPIR nPSize Training Course "Traceable Characterization of Nanoparticles by SAXS" CY - Online meeting DA - 01.02.2021 KW - Nanoparticles KW - Particle size distribution KW - Traceability KW - nPSize KW - SAXS PY - 2021 AN - OPUS4-53883 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pellegrino, Francesco A1 - Ortel, Erik A1 - Mielke, Johannes A1 - Schmidt, R. A1 - Maurino, V. A1 - Hodoroaba, Vasile-Dan T1 - Customizing New Titanium Dioxide Nanoparticles with Controlled Particle Size and Shape Distribution: A Feasibility Study Toward Reference Materials for Quality Assurance of Nonspherical Nanoparticle Characterization N2 - An overview is given on the synthesis of TiO2 nanoparticles with well-defined nonspherical shapes (platelet like, bipyramidal, and elongated), with the focus on controlled, reproducible synthesis, as a key requirement for the production of reference materials with homogeneous and stable properties. Particularly with regard to the nanoparticle shapes, there is a high need of certified materials, solely one material of this type being commercially available since a few months (elongated TiO2). Further, measurement approaches with electron microscopy as the golden method to tackle the nanoparticle shape are developed to determine accurately the size and shape distribution for such nonspherical particles. A prerequisite for accurate and easy (i.e., automated) image analysis is the sample preparation, which ideally must ensure a deposition of the nanoparticles from liquid suspension onto a substrate such that the particles do not overlap, are solvent-free, and have a high deposition density. Challenges in the Synthesis of perfectly monodispersed and solvent-free TiO2 nanoparticles of platelet and acicular shapes are highlighted as well as successful measurement approaches on how to extract from 2D projection electron micrographs the most accurate spatial information, that is, true 3D size, for example, of the bipyramidal nanoparticles with different geometrical orientations on a substrate. KW - Nanoparticles KW - Titanium dioxide KW - Reference materials KW - Standardisation KW - Particle size and shape distribution PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538849 DO - https://doi.org/10.1002/adem.202101347 VL - 24 IS - 6 SP - 1 EP - 10 PB - Wiley-VCH AN - OPUS4-53884 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cano Murillo, Natalia A1 - Szymoniak, Paulina A1 - Smales, Glen Jacob A1 - Sturm, Heinz A1 - Schönhals, Andreas T1 - Electrospun nanocomposites fibers of polycarbonate and taurine modified boehmite nanoparticles - What can be learned from structural and thermal investigations N2 - Though the reinforcing properties of inorganic particles in thermosetting nanocomposites, has been exploited, the integration of nanoparticles continues to be challenging in terms of their homogeneous distribution and their manipulation which can contribute to occupational hazards. Due to a second encapsulations of nanoparticles, electrospun nanocomposite fibers containing nanoparticles might be an alternative for overcoming these issues, as the fiber nonwovens contains the nanoparticles allowing for safer manipulation. Here, the morphology, and the thermal properties of electrospun polycarbonate fibers containing taurine modified boehmite nanoparticles (BNP) are investigated by means of small and wide-angle X-ray scattering as well as fast scanning and temperature modulated fast scanning calorimetry for the first time. The latter techniques allow the investigation of the thermal properties of single fibers at heating rates up to 10^4 K s^-1 keeping its structure intact. A quantitative analysis of the scattering data reveals a porous structure of the fibers. The porous structure is quantified regarding the pore volume and the pore size. A constant amount of aggregation is found even for the highly BNP loaded fibers. Thermal analysis on the fibers reveals a rigid amorphous fraction (RAF) where it is known that RAF determinates the properties of a nanocomposite to a large extent. For the fibers RAF amounts up to 40 wt%, which is essential higher compared to equally formulated PC/BNP composite cast films. The RAF in the case of the fibers, is not only due to the presence of particles in the polymer but also due to orientation effects induced by the electrospinning process. KW - Nanocomposite fibers KW - Electrospinning KW - X-ray scattering KW - Fast scanning calorimetry KW - Rigid amorphous fraction PY - 2021 DO - https://doi.org/10.1021/acsapm.1c01265 VL - 3 IS - 12 SP - 6572 EP - 6585 PB - ACS AN - OPUS4-53871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Legall, Herbert A1 - Bonse, Jörn A1 - Krüger, Jörg T1 - Emission of X-rays during ultrashort pulse laser processing N2 - Ultrashort pulse laser materials processing can be accompanied by the production of X-rays. Small doses per laser pulse can accumulate to significant dose rates at high laser pulse repetition rates which may exceed the permitted X-ray limits for human exposure. Consequently, a proper radiation shielding must be considered in laser machining. A brief overview of the current state of the art in the field of undesired generation of X-ray radiation during ultrashort pulse laser material processing in air is presented. T2 - Lasers in Manufacturing Conference 2021 CY - Online meeting DA - 21.06.2021 KW - Ultra-short pulse laser processing KW - Laser-induced X-ray emission KW - Radiation protection PY - 2021 SP - 1 EP - 5 AN - OPUS4-53866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kricheldorf, H. R. A1 - Weidner, Steffen A1 - Meyer, A. T1 - Poly(L-lactide): Optimization of Melting Temperature and Melting Enthalpy N2 - Twice recrystallized L-lactide was polymerized with a dozen of different tin or bismuth catalysts in bulk at 160°C for 24 h and was annealed at 150°C afterwards. In two cases Tm values above 197.0°C were obtained. The parameters causing a scattering of the DSC data were studied and discussed. The samples prepared with SnCl2, 2,2-dibutyl-2-stanna-1,3-ditholane (DSTL) or cyclic tin(II) bisphenyldioxide (SnBiph) were subject to annealing programs with variation of time and temperatures, revealing that the Tm´s did not increase. However, an increase of Hm was achieved with maximum values in the range of 93-96 J g-1 corresponding to crystallinities off around 90%. Further studies were performed with once recrystallized L-lactide. Again, those samples directly crystallized from the polymerization process showed the highest Tm values. These data were compared with the equilibrium Tm0 and Hm0 data calculated by several research groups for perfect crystallites. A Tm0 of 213+/-2°C and a Hm0 of 106 J g-1 show the best agreement with the experimental data. The consequences of annealing for the thickness growth of crystallites are discussed on the basis of SAXS measurements. Finally, a comparison of cyclic and linear poly L-lactide)s is discussed. KW - Polylactide KW - MALDI-TOF MS KW - Transesterification PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538656 DO - https://doi.org/10.1039/D1MA00957E SP - 1 EP - 10 PB - Royal Society for Chemistry AN - OPUS4-53865 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stolzenberg, U. A1 - Schmitt Rahner, M. A1 - Pullner, B. A1 - Legall, Herbert A1 - Bonse, Jörn A1 - Kluge, M. A1 - Ortner, A. A1 - Hoppe, B. A1 - Krüger, Jörg T1 - X-ray emission hazards from ultrashort pulsed laser material processing in an industrial setting N2 - Interactions between ultrashort laser pulses with intensities larger than 10^13 W/cm^2 and solids during material processing can lead to the emission of X-rays with photon energies above 5 keV, causing radiation hazards to operators. A framework for inspecting X-ray emission hazards during laser material processing has yet to be developed. One requirement for conducting radiation protection inspections is using a reference scenario, i.e., laser settings and process parameters that will lead to an almost constant and high level of X-ray emissions. To study the feasibility of setting up a reference scenario in practice, ambient dose rates and photon energies were measured using traceable measurement equipment in an industrial setting at SCHOTT AG. Ultrashort pulsed (USP) lasers with a maximum average power of 220 W provided the opportunity to measure X-ray emissions at laser peak intensities of up to 3.3 × 10^15 W/cm^2 at pulse durations of ~1 ps. The results indicate that increasing the laser peak intensity is insufficient to generate high dose rates. The investigations were affected by various constraints which prevented measuring high ambient dose rates. In this work, a list of issues which may be encountered when performing measurements at USP-laser machines in industrial settings is identified. KW - X-ray emission hazards KW - Ultrashort pulsed laser KW - Radiation protection KW - Industrial applications KW - Protection housing PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538632 DO - https://doi.org/10.3390/ma14237163 SN - 1996-1944 VL - 14 SP - 1 EP - 17 PB - MDPI CY - Basel AN - OPUS4-53863 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Musl, O. A1 - Sulaeva, I. A1 - Sumerskii, I. A1 - Mahler, A.K. A1 - Rosenau, T. A1 - Falkenhagen, Jana A1 - Potthast, A. T1 - Mapping of the Hydrophobic Composition of Lignosulfonates N2 - Lignosulfonates are industrial biorefinery products that are characterized by significant variability and heterogeneity in their structural composition. Typically, they exhibit high dispersities in molar mass (molar mass distribution-MMD) and in functionalities (functionality-type distribution - FTD), which crucially affect their material usage. In terms of FTD, state-of-the-art Lignin analytics still rely mainly on the determination of functional group contents, which are statistical averages with limited explanatory power. In contrast, our online hydrophobic interaction chromatography−size-exclusion chromatography 2D-LC approach combines the determination of both MMD and FTD in a single measurement to provide a comprehensive picture of the characteristic composition of industrial lignosulfonates information hitherto inaccessible by state-of-the-art lignin analytics. In this way, the complex inter - relationships between these two important structural parameters can be studied in an unprecedented manner. In this study, we reveal the considerable differences in terms of hydrophobic composition and its dispersity present in a range of different industrial lignosulfonates - data desperately needed in tailoring and refining of lignosulfonate composition for material usage. KW - Lignosulfonates KW - Amphiphilicity KW - Hydrophobic interaction chromatography KW - Two-dimensional chromatography (2D-LC) KW - Charge-to-size-ratio PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538612 DO - https://doi.org/10.1021/acssuschemeng.1c06469 VL - 9 IS - 49 SP - 16786 EP - 16795 PB - ASC Publications AN - OPUS4-53861 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zorn, R. A1 - Szymoniak, Paulina A1 - Kolmangadi, Mohamed Aejaz A1 - Malpass-Evans, R. A1 - McKeown, N. A1 - Tyagi, M. A1 - Böhning, Martin A1 - Schönhals, Andreas T1 - Low frequency vibrations and diffusion in disordered polymers bearing an intrinsic microporosity as revealed by neutron scattering N2 - The microscopic diffusion and the low frequency density of states (VDOS) of PIM-EATB(CH3) are investigated by inelastic and quasi-elastic neutron scattering where also the demethylated counterpart of PIM-EA-TB(H2) is considered. These intrinsic microporous polymers are characterized by large BET surface area values of several hundred m2/g and pore sizes between 0.5 and 2 nm. Detailed comparison is made to the archetype of polymers of intrinsic microporosity, PIM-1, and polynorbornenes also bearing a microporosity. Due to the wavelength of neutrons, the diffusion and vibrations can be addressed on microscopic length and time scales. From the inelastic neutron scattering experiments the low frequency density of states (VDOS) is estimated which shows excess contributions to the Debye-type VDOS known as Boson peak. It was found that the maximum frequency of the Boson peak decreases with increasing microporosity characterized by the BET surface area. However, besides the BET surface area, additional factors such as the backbone stiffness govern the maximum frequency of the Boson peak. Further the mean squared displacement related to microscopic motions was estimated from elastic fixed window scans. At temperatures above 175 K, the mean squared displacement PIM-EA-TB(CH3) is higher than that for the demethylated counterpart PIM-EA-TB(H2). The additional contribution found for PIM-EATB(CH3) is ascribed to the rotation of the methyl group in this polymer because the only difference between the two structures is that PIM-EA-TB(CH3) has methyl groups where PIM-EA-TB(H2) has none. A detailed comparison of the molecular dynamics is also made to that of PIM-1 and the microporous polynorbornene PTCNSi1. The manuscript focuses on the importance of vibrations and the localized molecular mobility characterized by the microscopic diffusion on the gas Transport in polymeric separation membranes. In the frame of the random gate model localized fluctuations can open or close bottlenecks between pores to enable the diffusion of gas molecules. KW - Polymer of intrisic microporosity KW - Neutron scattering KW - Boson peak KW - Methyl group rotation PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-538490 DO - https://doi.org/10.3390/cryst11121482 VL - 11 IS - 12 SP - 1 EP - 16 PB - MDPI CY - Basel AN - OPUS4-53849 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - George, Janine T1 - New chemical understanding with the help of automation and highthroughput computations N2 - High-throughput computations are nowadays an established way to suggest new candidate materials for applications to experimentalists. Due to new packages for automation and access to databases of computed materials properties, these studies became more and more complex over the last years. Besides suggesting new candidate materials for applications, they also offer a way to understanding the materials properties based on chemical bonds. For example, we have recently used orbital-based bonding analysis to understand the results of high-throughput studies for spintronic materials, ferroelectric materials and photovoltaic materials in detail. To do so, we have developed Python tools for high-throughput bonding analysis with the programs VASP and Lobster (see www.cohp.de). They are based on the Python packages pymatgen, atomate, and custodian. This implementation will be discussed within the talk. We also expect that these tools offer possibilities to arrive at new descriptors based on chemical bonds for materials properties. T2 - High-throughput workflows for materials science with the Atomic Simulation Environment (ASE) and Fireworks CY - Lyngby, Denmark DA - 15. November 2021 KW - Automation KW - High-throughput computations KW - DFT PY - 2021 AN - OPUS4-53840 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Axel A1 - Braun, U A1 - Altmann, Korinna T1 - Representative sampling of roadside soil and determination of tire wear contents by TED-GC/MS N2 - The presentation describes microplastic findings from tyre wear near roads. Both the sampling and the analysis are presented. T2 - Mikroplastik Workshop der Hochschule Zittau CY - Online meeting DA - 25.11.2021 KW - Mikroplastik KW - Reifenabrieb KW - TED-GC/MS KW - Probennahme PY - 2021 AN - OPUS4-53831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna T1 - Systemverständnis und Untersuchungsstrategien von Kunststoffeinträgen in die Umwelt – Ergebnisse des RUSEKU-Forschungsprojektes N2 - Ziel des Vortrages ist die Vermittlung der Herausforderungen der Mikroplastik-Analytik sowie der Harmonisierung der Analytik und des Ergebnistransfers in die Normung. T2 - Jahresabschluss-Sitzung GA "Mensch und Umwelt" CY - Online meeting DA - 24.11.2021 KW - Mikroplastik KW - Mikroplastik-Analytik PY - 2021 AN - OPUS4-53830 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wiesner, Yosri A1 - Altmann, Korinna T1 - MIKROPLASTIK – von der Probenvorbereitung bis zur Analytik N2 - Der Vortrag beschreibt die Herausforderungen bei der Analyse von Mikroplastik inklusive Probennahme, Probenvorbereitung und Detektion. Es werden Ergebnisse aus dem BMBF-Projekt RUSEKU vorgestellt. T2 - LABO-Anwendertag CY - Online meeting DA - 23.11.2021 KW - Mikroplastik KW - TED-GC/MS KW - Mikroplastik-Analytik PY - 2021 AN - OPUS4-53829 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Harald A1 - Rühle, Bastian A1 - Hodoroaba, Vasile-Dan A1 - Resch-Genger, Ute A1 - Kuchenbecker, Petra A1 - Abram, Sarah-Luise A1 - Löhmann, Oliver A1 - Mrkwitschka, Paul T1 - Tour de table - BAM N2 - Kurzübersicht über die neuen Aktivitäten zu Nanomaterialien in 2021. T2 - Nano-Behördenklausur der Bundesoberbehörden 2021 CY - Online meeting DA - 17.11.2021 KW - Nano KW - Nanomaterial KW - Nanopartikel KW - Bundesoberbehörden PY - 2021 AN - OPUS4-53827 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stawski, Tomasz A1 - Smales, Glen Jacob A1 - Scoppola, E. A1 - Jha, D. A1 - Morales, L. F. G. A1 - Moya, A. A1 - Wirth, R. A1 - Pauw, Brian Richard A1 - Emmerling, Franziska A1 - Van Driessche, A. E. S. T1 - Seeds of imperfection rule the mesocrystalline disorder in natural anhydrite single crystals N2 - In recent years, we have come to appreciate the astounding intricacies associated with the formation of minerals from ions in aqueous solutions. In this context, a number of studies have revealed that the nucleation of calcium sulfate systems occurs nonclassically, involving the aggregation and reorganization of nanosized prenucleation species. In recent work, we have shown that this particle-mediated nucleation pathway is actually imprinted in the resultant micrometer-sized CaSO4 crystals. This property of CaSO4 minerals provides us with the unique opportunity to search for evidence of nonclassical nucleation pathways in geological environments. In particular, we focused on large anhydrite Crystals extracted from the Naica Mine in Mexico. We were able to shed light on this mineral's growth history by mapping defects at different length scales. Based on this, we argue that the nanoscale misalignment of the structural subunits, observed in the initial calcium sulfate crystal seeds, propagates through different length scales both in morphological, as well as in strictly crystallographic aspects, eventually causing the formation of large mesostructured single crystals of anhydrite. Hence, the nonclassical nucleation mechanism introduces a “seed of imperfection,” which leads to a macroscopic “single” crystal whose fragments do not fit together at different length scales in a self-similar manner. Consequently, anisotropic voids of various sizes are formed with very welldefined walls/edges. However, at the same time, the material retains in part its single crystal nature. KW - Calcium sulfate KW - Anhydrite KW - Mesocrystal KW - Nucleation KW - Naica PY - 2021 DO - https://doi.org/10.1073/pnas.2111213118 SN - 0027-8424 VL - 118 IS - 48 SP - 1 EP - 11 PB - National Academy of Sciences (USA) CY - Washington AN - OPUS4-53820 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pauw, Brian Richard A1 - Smales, Glen Jacob T1 - How to manage a modern X-ray scattering lab – a modest example N2 - Introduction A good laboratory organization can help address the reproducibility crisis in science, and easily multiply the scientific output of a laboratory, while greatly elevating the quality of the measurements. We have demonstrated this for small- and wide-angle X-ray scattering in the MOUSE project (Methodology Optimization for Ultrafine Structure Exploration). In the MOUSE, we have combined: a) a comprehensive laboratory workflow with b) a heavily modified, highly automated X-ray scattering instrument. This combination allows us to collect fully traceable scattering data, with a well-documented data flow (akin to what is found at the more automated beamlines). With two full-time researchers, the lab collects and interprets thousands of datasets, on hundreds of samples for dozens of projects per year, supporting many users along the entire process from sample selection and preparation, to the analysis of the resulting data. While these numbers do not light a candle to those achieved by our hardworking compatriots at the synchrotron beamlines, the laboratory approach does allow us to continually modify and fine-tune the integral methodology. So for the last three years, we have incorporated e.g. FAIR principles, traceability, automated processing, data curation strategies, as well as a host of good scattering practices into the MOUSE system. We have concomitantly expanded our purview as specialists to include an increased responsibility for the entire scattering aspect of the resultant publications. This ensures full exploitation of the data quality, whilst avoiding common pitfalls. Talk scope This talk will present the MOUSE project as implemented to date, and will introduce foreseeable upgrades and changes. These upgrades include better pre-experiment sample scattering predictions to filter projects on the basis of their suitability, exploitation of the measurement database for detecting long-term changes and automated flagging of datasets, extending the measurement range through an Ultra-SAXS module, and enhancing MC fitting with sample scattering simulations for better matching of odd-shaped scatterers. T2 - 2021 joint virtual meeting of the African Light Source (AfLS), the African Physical Society (AfPS), and Pan African Conference on Crystallography (ePCCr) CY - Online meeting DA - 15.11.2021 KW - X-ray scattering KW - MOUSE KW - Instrumentation KW - SAXS KW - Methodology KW - Laboratory management KW - Databases KW - Data management KW - Data catalog KW - Scicat PY - 2021 UR - https://events.saip.org.za/event/170/contributions/7619/ AN - OPUS4-53811 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pauw, Brian Richard A1 - Smales, Glen Jacob T1 - X-ray Scattering for Nanostructure Quantification, and the Quest for the Perfect Experiment N2 - Compared to the clear, real-space images you can get from electron microscopy, X-ray scattering patterns are rather featureless. These patterns, however, contain structural information from all of the material structure illuminated by the X-ray beam. With this technique, you can measure nanoparticle dispersions, catalysts, composites, MOF powders, battery materials, light metal alloys and gels to reveal information on the structural features found within these materials. We have even measured many such materials for several research groups from the University of Birmingham, revealing structure features in the sub-nm to the micrometer range. Measuring an X-ray scattering pattern is relatively easy, but measuring a high-quality, useful pattern requires significant effort and good laboratory organization. Such laboratory organization can help address the reproducibility crisis in science, and easily multiply the scientific output of a laboratory, while greatly elevating the quality of the measurements. We have demonstrated this for small- and wide-angle X-ray scattering in the MOUSE project (Methodology Optimization for Ultrafine Structure Exploration) [1]. With the MOUSE, we have combined: a) a comprehensive and highly automated laboratory workflow with b) a heavily modified X-ray scattering instrument. This combination allows us to collect fully traceable scattering data, within a well-documented, FAIR-compliant data flow (akin to what is found at the more automated synchrotron beamlines). With two full-time researchers, our lab collects and interprets thousands of datasets, on hundreds of samples, for dozens of projects per year, supporting many users along the entire process from sample selection and preparation, to the analysis of the resulting data. T2 - School of Chemistry Seminars CY - Birmingham, UK DA - 10.11.2021 KW - X-ray scattering KW - MOUSE KW - Instrumentation KW - SAXS KW - Methodology KW - Nanostructure PY - 2021 UR - https://www.youtube.com/watch?v=N2kY4wbqeM4 AN - OPUS4-53810 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wetzel, Annica A1 - Özcan Sandikcioglu, Özlem A1 - Witt, Julia A1 - Rhode, Michael T1 - Corrosion Properties and Protective Oxide Film Characteristics of CrMnFeCoNi High Entropy Alloy and CrCoNi Medium Entropy Alloy N2 - High and medium entropy alloys gained increasing academic and industrial interest as novel materials for engineering applications. This project is aiming to clarify and compare the general and local corrosion properties of high entropy alloy CrMnFeCoNi and medium entropy alloy CrCoNi in different aqueous environments. The focus lies on the local corrosion processes that result either from microstructural imperfections (inclusions, defects at grain boundaries etc.) in the base material or processing related changes in the microstructure and/or local composition. The corrosion behavior of the alloys was monitored via potentiodynamic polarization experiments and the local corrosion characteristics were further investigated by means of scanning electrochemical microscopy (SECM). Their passivation behavior was analyzed in three different electrolyte systems (NaCl, H2SO4 and NaClO4; c = 0.1M). The characterization of the surface morphology and composition of the passive film was performed by means of atomic force microscopy (AFM), scanning electron microscopy coupled with energy dispersive X-Ray spectroscopy (SEM/EDX) and X-Ray photoelectron spectroscopy (XPS), respectively. Considering long term corrosion effects, electrochemical work was supported with immersion tests and the analysis of corrosion products by SEM/EDX and XPS depth-profiling. Our results indicate that the medium entropy alloy CrCoNi has a significantly higher corrosion resistance due to the higher concentration of Chromium in comparison to the high entropy alloy CrMnFeCoNi. The presentation will summarize our results on the mechanistical aspects of the observed high corrosion resistance. T2 - EUROCORR 2021 CY - Online meeting DA - 20.09.2021 KW - High Entropy Alloys KW - Aqueous Corrosion KW - Medium Entropy Alloys KW - Atomic Forc Microscopy KW - Scanning Kelvin Probe Force Microscopy KW - Potentiodynamic Polarization KW - Electrochemical Impedance Spectroscopy KW - ICP-MS PY - 2021 AN - OPUS4-53791 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wetzel, Annica A1 - Özcan Sandikcioglu, Özlem A1 - Witt, Julia A1 - Rhode, Michael T1 - Corrosion Properties and Protective Oxide Film Characteristics of CrMnFeCoNi High Entropy Alloy and CrCoNi Medium Entropy Alloy N2 - High and medium entropy alloys gained increasing academic and industrial interest as novel materials for engineering applications. This project is aiming to clarify and compare the general and local corrosion properties of high entropy alloy CrMnFeCoNi and medium entropy alloy CrCoNi in different aqueous environments. The focus lies on the local corrosion processes that result either from microstructural imperfections (inclusions, defects at grain boundaries etc.) in the base material or processing related changes in the microstructure and/or local composition. The corrosion behavior of the alloys was monitored via potentiodynamic polarization experiments and the local corrosion characteristics were further investigated by means of scanning electrochemical microscopy (SECM). Their passivation behavior was analyzed in three different electrolyte systems (NaCl, H2SO4 and NaClO4; c = 0.1M). The characterization of the surface morphology and composition of the passive film was performed by means of atomic force microscopy (AFM), scanning electron microscopy coupled with energy dispersive X-Ray spectroscopy (SEM/EDX) and X-Ray photoelectron spectroscopy (XPS), respectively. Considering long term corrosion effects, electrochemical work was supported with immersion tests and the analysis of corrosion products by SEM/EDX and XPS depth-profiling. Our results indicate that the medium entropy alloy CrCoNi has a significantly higher corrosion resistance due to the higher concentration of Chromium in comparison to the high entropy alloy CrMnFeCoNi. The presentation will summarize our results on the mechanistical aspects of the observed high corrosion resistance. T2 - EuroMat 2021 CY - Online meeting DA - 12.09.21 KW - High Entropy Alloys KW - Aqueous Corrosion KW - Medium Entropy Alloys KW - Atomic Forc Microscopy KW - Scanning Kelvin Probe Force Microscopy KW - Potentiodynamic Polarization KW - Electrochemical Impedance Spectroscopy KW - ICP-MS PY - 2021 AN - OPUS4-53790 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wetzel, Annica A1 - Özcan Sandikcioglu, Özlem A1 - Witt, Julia A1 - Rhode, Michael T1 - Corrosion Properties and Protective Oxide Film Characteristics of CrMnFeCoNi High Entropy Alloy and CrCoNi Medium Entropy Alloy N2 - High and medium entropy alloys gained increasing academic and industrial interest as novel materials for engineering applications. This project is aiming to clarify and compare the general and local corrosion properties of high entropy alloy CrMnFeCoNi and medium entropy alloy CrCoNi in different aqueous environments. The focus lies on the local corrosion processes that result either from microstructural imperfections (inclusions, defects at grain boundaries etc.) in the base material or processing related changes in the microstructure and/or local composition. The corrosion behavior of the alloys was monitored via potentiodynamic polarization experiments and the local corrosion characteristics were further investigated by means of scanning electrochemical microscopy (SECM). Their passivation behavior was analyzed in two different electrolyte systems (NaCl and H2SO4 c = 0.1M). The characterization of the surface morphology and composition of the passive film was performed by means of atomic force microscopy (AFM), scanning electron microscopy coupled with energy dispersive X-Ray spectroscopy (SEM/EDX) and X-Ray photoelectron spectroscopy (XPS), respectively. To analyze the semiconducting properties of the passive film Mott-Schottky analysis was conducted. Considering long term corrosion effects, electrochemical work was supported with immersion tests and the analysis of corrosion products by SEM/EDX, ICP-MS and XPS depth-profiling. Our results indicate that the medium entropy alloy CrCoNi has a significantly higher corrosion resistance due to the higher concentration of chromium in comparison to the high entropy alloy CrMnFeCoNi. The presentation will summarize our results on the mechanistical aspects of the observed high corrosion resistance. T2 - ISE Annual 72nd meeting CY - Online meeting DA - 29.08.2021 KW - High Entropy Alloys KW - Aqueous Corrosion KW - Medium Entropy Alloys KW - Atomic Forc Microscopy KW - Scanning Kelvin Probe Force Microscopy KW - Potentiodynamic Polarization KW - Electrochemical Impedance Spectroscopy KW - ICP-MS PY - 2021 AN - OPUS4-53789 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Stawski, Tomasz A1 - Smales, Glen Jacob A1 - Scoppola, E. A1 - Jha, D. A1 - Morales, L. F. G. A1 - Moya, A. A1 - Wirth, R. A1 - Pauw, Brian Richard A1 - Emmerling, Franziska A1 - Van Driessche, A. E. S. T1 - Supplementary data set for "Seeds of imperfection rule the mesocrystalline disorder in natural anhydrite single crystals" N2 - In recent years, we have come to appreciate the astounding intricacy of the formation process of minerals from ions in aqueous solutions. In this context, a number of studies have revealed that nucleation in the calcium sulfate system is non-classical, involving the aggregation and reorganization of nanosized prenucleation particles. In a recent work we have shown that this particle-mediated nucleation pathway is actually imprinted in the resultant single micron-sized CaSO4 crystals. This property of CaSO4 minerals provides us with an unique opportunity to search for evidence of non-classical nucleation pathways in geological environments. In particular, we focused on the quintessential single crystals of anhydrite extracted from the Naica mine in Mexico. We elucidated the growth history from this mineral sample by mapping growth defects at different length scales. Based on these data we argue that the nano-scale misalignment of the structural sub-units observed in the initial calcium sulfate crystal seed propagate through different length-scales both in morphological, as well as strictly crystallographic aspects, eventually causing the formation of large mesostructured single crystals of anhydrite. Hence, the nanoparticle mediated nucleation mechanism introduces a 'seed of imperfection', which leads to a macroscopic single crystal, in which its fragments do not fit together at different length-scales in a self-similar manner. Consequently, anisotropic voids of various sizes are formed with very well-defined walls/edges. But, at the same time the material retains its essential single crystal nature. These findings shed new light on the longstanding concept of crystal structure. KW - Calcium sulfate KW - Mesocrystal KW - Anhydrite PY - 2021 DO - https://doi.org/10.5281/zenodo.4943234 PB - Zenodo CY - Geneva AN - OPUS4-53765 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hildebrandt, Jana A1 - Thünemann, Andreas T1 - PP and PE nanoplastics in water N2 - Plastic debris in micron and nanometer scale pollutes the nature all over the world. The potential dangers of these pollutants remain unpredictable. While risk assessment studies on microplastics are already popular, nanoplastic has not yet reached the same focus of investigation. The reason for this difference is simple: There is a "methodological gap" in the analytics of plastic particles with a diameter smaller than 1 μm. Submicron and nanoplastic particles are currently not detectable in environmental matrices. Therefore, it is important for researchers to have a well-characterized nanoplastic material, that serves as a reference for nanoplastics found in nature. Our aim was to synthesize nanoplastics made from the most common used plastics such as polypropylene (PP) and polyethylene (PE). We found an easy way to form nanoparticles consisting of PP and PE (nano-PP/PE). Herein, nano-PP/PE was formed via a top-down method where the polymer was dispersed to acetone and then transferred to water. No surfactant is needed to obtain a dispersion which is stable for more than 35 weeks. The success of forming nanoplastics and their size was detected via scattering methods, predominantly dynamic light scattering. The chemical analysis of the nanoplastics was performed via Fourier Transform Infrared spectroscopy. Furthermore, electron microscopy was used to complement the results. To examine the good stability of the nanoparticles, zeta potential measurements were performed, which revealed zeta potentials of -30 to -40 mV. T2 - IUPAC-MACRO2020+ CY - Online meeting DA - 17.05.2021 KW - Nanoplastic PY - 2021 AN - OPUS4-53774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hildebrandt, Jana A1 - Thünemann, Andreas T1 - Polypropylene and polyethylene nanoplastics in water N2 - Considering the huge amount of plastics, that is produced and thrown away all over the world every day, an increasing part of the society became aware of microplastic and its possible impact on the environment. Polymer particles smaller than 1 µm are called nanoplastic. Due to their small size they form a special group within particulate waste. Their high specific surface makes it easier for them to penetrate tissue and pose potential harm. On the other hand, the size and the chemical structure make it difficult to detect and analyze nanoplastics in nature. Furthermore, the concentrations in environmental samples are very low. Therefore, there is a need for a well-characterized nanoplastic material, that serves as a reference for nanoplastic found in nature. T2 - Tag der Chemie 2021 Uni Potsdam CY - Online meeting DA - 06.07.2021 KW - Nanoplastic PY - 2021 AN - OPUS4-53775 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hildebrandt, Jana A1 - Thünemann, Andreas T1 - Preparation of polypropylene and polyethylene nanoplastics in water N2 - Considering the huge amount of plastics, that is produced and thrown away all over the world every day, an increasing part of the society became aware of microplastic and its possible impact on the environment. Polymer particles smaller than 1 µm are called nanoplastic. Due to their small size they form a special group within particulate waste. Their high specific surface makes it easier for them to penetrate tissue and pose potential harm. On the other hand, the size and the chemical structure make it difficult to detect and analyze nanoplastics in nature. Furthermore, the concentrations in environmental samples are very low. Therefore, there is a need for a well-characterized nanoplastic material, that serves as a reference for nanoplastic found in nature. T2 - 101 years of Macromolecular Chemistry CY - Online meeting DA - 13.09.2021 KW - Nanoplastic PY - 2021 AN - OPUS4-53773 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Bonse, Jörn A1 - Kirner, Sabrina V. A1 - Krüger, Jörg ED - Sugioka, K. T1 - Laser-Induced Periodic Surface Structures (LIPSS) N2 - Laser-induced periodic surface structures (LIPSS) are a universal phenomenon and can be generated on almost any material by irradiation with linearly polarized radiation. This chapter reviews the current state in the field of LIPSS, which are formed in a “self-ordered” way and are often accompanying materials processing applications. LIPSS can be produced in a single-stage process and enable surface nanostructuring and, in turn, adaption of optical, mechanical, and chemical surface properties. Typically, they feature a structural size ranging from several micrometers down to less than 100 nm and show a clear correlation with the polarization direction of the light used for their generation. Various types of LIPSS are classified, relevant control parameters are identified, and their material-specific formation mechanisms are analyzed for different types of inorganic solids, i.e., metals, semiconductors, and dielectrics. Finally, technological applications featuring surface functionalization in the fields of optics, fluidics, medicine, and tribology are discussed. KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser KW - Laser ablation KW - Microstructures KW - Nanostrcutures PY - 2021 SN - 978-3-030-63646-3 (Print) SN - 978-3-030-63647-0 (Online) DO - https://doi.org/10.1007/978-3-030-63647-0_17 SP - 879 EP - 936 PB - Springer-Nature Switzerland AG CY - Cham ET - 1 AN - OPUS4-53728 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Zarinwall, A. A1 - Waniek, Tassilo A1 - Finke, B. A1 - Sadaat, R. A1 - Sturm, Heinz A1 - Garnweitner, G. ED - Sinapius, M. ED - Ziegmann, G. T1 - Particle Surface Modification N2 - Whilst a decisive role of the particle-matrix interphase on the mechanical properties of nanoparticle-filled polymers has been demonstrated in the last years, the arbitrary design of this interphase remains a very challenging goal. In principle, this could be realized via an appropriate surfacemodification of the nanofiller prior to its incorporation in the polymer. For most systems, such as for boehmite nanofillers, however, the interaction of organic modifiers with the particle surface has not been studied in detail, and only single studies are known rather than systematic investiga- tions on the effects of different chemical functions anchored on the particle surface. In this chapter, we present an extensive study on the binding of APTES, a common silane surface modifier, with boehmite, and show that thermogravimetric analysis (TGA) coupled with mass spectrometry (MS) is a convenient and highly suitable method to elucidate the ligand binding in detail. Furthermore, a two-step coupling strategy is presented, demonstrating that based on APTES anchored to the parti- cle surface, the condensation of various carboxylic acids can be utilized to enable highly diverse chemical properties of the nanofillers, which leads to very different particle-matrix interactions in the nanocomposites. KW - APTES KW - Boehmite KW - Nanoparticle KW - TGA-MS PY - 2021 SN - 978-3-030-68522-5 SN - 978-3-030-68523-2 DO - https://doi.org/10.1007/978-3-030-68523-2 SN - 2194-8240 SN - 2194-8259 SP - 119 EP - 142 PB - Springer Nature Switzerland AG CY - Cham AN - OPUS4-53727 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Anja A1 - Buchberger, G. A1 - Stifter, D. A1 - Duchoslav, J. A1 - Hertwig, Andreas A1 - Bonse, Jörn A1 - Heitz, J. A1 - Schwibbert, Karin T1 - Spatial Period of Laser-Induced Surface Nanoripples on PET Determines Escherichia coli Repellence N2 - Bacterial adhesion and biofilm formation on surfaces are associated with persistent microbial contamination, biofouling, and the emergence of resistance, thus, calling for new strategies to impede bacterial surface colonization. Using ns-UV laser treatment (wavelength 248 nm and a pulse duration of 20 ns), laser-induced periodic surface structures (LIPSS) featuring different submicrometric periods ranging from ~210 to ~610 nm were processed on commercial poly(ethylene terephthalate) (PET) foils. Bacterial adhesion tests revealed that these nanorippled surfaces exhibit a repellence for E. coli that decisively depends on the spatial periods of the LIPSS with the strongest reduction (~91%) in cell adhesion observed for LIPSS periods of 214 nm. Although chemical and structural analyses indicated a moderate laser-induced surface oxidation, a significant influence on the bacterial adhesion was ruled out. Scanning electron microscopy and additional biofilm studies using a pili-deficient E. coli TG1 strain revealed the role of extracellular appendages in the bacterial repellence observed here. KW - Laser-induced periodic surface structures (LIPSS) KW - Laser processing KW - Polyethylene terephthalate KW - Biofilm formation KW - Cell appendages KW - Biomimetic KW - F pili PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537431 DO - https://doi.org/10.3390/nano11113000 VL - 11 IS - 11 SP - 3000 PB - MDPI AN - OPUS4-53743 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Roszak, I. A1 - Oswald, L. A1 - Ouahabi, A. A. A1 - Bertin, Annabelle A1 - Laurent, E. A1 - Felix, O. A1 - Carvin-Sergent, I. A1 - Charles, L. A1 - Lutz, J.-F. T1 - Synthesis and sequencing of informational poly(amino phosphodiester)s N2 - Sequence-defined poly(amino phosphodiester)s containing main-chain tertiary amines were synthesized by automated solid-phase phosphoramidite chemistry. These polymers were prepared using four monomers with different substituents. The formed polymers were characterized by HPLC and mass spectrometry. These methods evidenced preparation of molecularly-defined polymers. Furthermore, the presence of tertiary amines in the polymer backbones facilitates sequencing by tandem mass spectrometry. KW - Poly(amino phosphodiester) KW - Synthesis KW - HPLC KW - Mass spectrometry PY - 2021 DO - https://doi.org/10.1039/d1py01052b SN - 1759-9954 VL - 12 IS - 37 SP - 5279 EP - 5282 PB - Royal Society of Chemistry AN - OPUS4-53732 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna A1 - Uzunlu, Büsra A1 - Ciornii, Dmitri A1 - Hodoroaba, Vasile-Dan A1 - Waniek, Tassilo T1 - Update – Milling and weathering of granules N2 - The talk aims to describe the production of microplastic particles as test material and the additional weathering for aged particles. T2 - PlasticsFate meeting CY - Online meeting DA - 12.11.2021 KW - Microplastic KW - Cryo milling KW - Aged particles PY - 2021 AN - OPUS4-53737 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna T1 - Mikroplastik – Ein Problem für die Menschheit? N2 - Mikroplastik findet sich in Ozeanen, Seen, Flüssen und Bächen. Es kann in unserem Boden, in der Luft und sogar in Organismen nachgewiesen werden. Jedes Jahr werden weltweit Millionen Tonnen freigesetzt. Doch wo und wie landet Mikroplastik in der Umwelt? Und wie können wir diese winzigen Partikel nachweisen? T2 - Berlin Science Week CY - Berlin, Germany DA - 01.11.2021 KW - Mikroplastik KW - TED-GC/MS PY - 2021 AN - OPUS4-53734 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Altmann, Korinna T1 - Microplastics at BAM: TED-GC/MS and reference materials N2 - Thsi talk aims to present the activities of microplastic analysis at BAM according to TED-GC/MS and reference materials developement. T2 - Webinar BAM / University of Birmingham CY - Online meeting DA - 15.06.2021 KW - Microplastic KW - TED-GC/MS KW - Reference materials PY - 2021 AN - OPUS4-53738 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Griepentrog, Michael A1 - Hertwig, Andreas A1 - Hielscher-Hofinger, S. A1 - Lange, Thorid A1 - Weise, Matthias T1 - Uncertainty budgets in surface techno-logy: step height, layer thickness, indentation hardness, adehesive strength N2 - The object (sample) and the measurement/testing procedure may always have unknown degrees of freedom, i.e. instead of 𝐯 ≥ n – 1 in many cases 𝐯 ≫ n - 1 may apply, in particular in the micro- and nano-world! T2 - 10. VDI-Fachtagung, Messunsicherheit und Prüfprozesse CY - Erfurt, Germany DA - 10.11.2021 KW - Methodology in metrology KW - Methodology in testing KW - Spectroscopic Ellipsometry KW - Instrumented Indentation (IIT) KW - Centrifugal Adhesion Testing (CAT) PY - 2021 AN - OPUS4-53739 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -