TY - CONF A1 - Braun, Ulrike T1 - Entwicklung einer schnellen und robusten Methode für die Analytik von Mikroplastik in Wasser N2 - Vortrag im Rahmen der Preisverleihung zum Mülheimer Wasser Award 2018, Vorstellung der TED-GC-MS als Methode für Mikroplastik Analyse T2 - 3. Wasseranalytisches Seminar (MWAS 2018) CY - Mülheim a.d. Ruhr, Germany DA - 12.09.2018 KW - Mikroplastik KW - Analytik PY - 2018 AN - OPUS4-46459 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Von Ägypten bis Hiddensee – Analyse von Gold mit Synchrotronstrahlung - Update 2018 N2 - Gold ist eines der sieben schon im Altertum bekannten Metalle und wurde wg. seines Glanzes und seiner Seltenheit von alters her als Tauschmittel und zur Herstellung von Schmuck benutzt. Außerdem ist es einfach bearbeitbar und weitestgehend gegen chemische Einflüsse resistent. Die Untersuchungen von Gold mit synchrotronstrahlungsangeregter Röntgenfluoreszenzanalyse sind zerstörungsfrei und geben Auskunft über die in der untersuchten Probe vorhandenen chemischen Elemente. Bei den hier vorgestellten Untersuchungen an der BAMline stehen Fragestellungen wie Herkunft, Herstellungsverfahren und Zusammengehörigkeit von Goldfunden im Vordergrund. Die verschiedenen Fragestellungen werden an einer Reihe von Beispielen erläutert die vom Wikingerschatz aus Hiddensee über die Himmelsscheibe von Nebra bis hin zu Funden aus Ägypten langen. Zusätzlich werden die modernen Messmethoden vorgestellt, die am Synchrotron heutzutage zur Verfügung stehen. T2 - Vorlesung FU Berlin Einführung in die Archäometrie CY - Berlin, Germany DA - 01.11.2018 KW - Gold KW - Synchrotron KW - XRF KW - BAMline PY - 2018 AN - OPUS4-46451 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Saadeh, Qais A1 - Pauw, Brian Richard A1 - Thünemann, Andreas A1 - Günster, Jens T1 - In-Situ SAXS Techniques N2 - Our project's aim is to enhance the capabilities of additive manufacturing techniques, where enabling a Two-Photon-Polymerization (TPP) 3D printer of producing arrays of precisely aligned nanoparticles is of an enormous value. As heterogeneous functional nanostructures with arrays of oriented nanoparticles are very promising in many fields; electrochemistry, energy storage, nanoelectronics among other vital fields. The feasibility and the convenience of orienting nanoparticles using magnetic, electric fields and ultrasonic vibrations will be systematically investigated, using Small Angle X-ray Scattering (SAXS), since SAXS can provide detailed information about the orientation characteristics of nano-Ensembles. Corresponding to our prerequisites, a set ad hoc functional sample holders, sample stages and other In-Situ SAXS solutions were developed, and incorporated to be compatible with a state-of-the-arts SAXS machine, called Multi-scale Analyzer for Ultrafine Structures (MAUS). The MAUS has been customized and engineered to serve as a miniaturized synchrotron, and that is exactly what we need. Experiments attempting to orient superparamagnetic nanoparticles will be discussed, where the outcomes will not only help in understanding the mechanics of field-particle interactions, it will also help in further developing the adequate needed set of corrections to the SAXS data, that is especially regards oriented samples. T2 - XVII International Small Angle Scattering Conference – SAS 2018 CY - Traverse City, Michigan, USA DA - 07.10.2018 KW - In-Situ Techniques KW - SAXS KW - Magnetic nano-particles PY - 2018 AN - OPUS4-46443 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gollwitzer, Christian A1 - Ulbricht, Alexander A1 - Scholz, Philipp A1 - Joshi, Yogita A1 - Weidner, Steffen T1 - 3D printing material filled with metal organic frameworks analyzed by synchrotron based absorption edge tomography N2 - Absorption edge tomography, also known as differential tomography at absorption edges, is a method which exploits the sudden change of the attenuation coefficient, when the photon energy crosses the absorption edge of an element. Synchrotron radiation is the best source for absorption edge tomography, because of its small bandwidth, high intensity and easily adjustable photon energy. The synchrotron beamline BAMline at the synchrotron radiation facility BESSY II in Berlin, which is operated by the Bundesanstalt für Materialforschung und -prüfung (BAM), provides a monochromatized beam in a photon energy range from 5 keV up to 80 keV with a bandwidth of 2%, when the double multilayer monochromator is used. Together with the microtomography setup, this enables differential tomography with submicron resolution at the K edge of the elements from chromium up to the lanthanides, and up to uranium, when the L edges are used as well. In this work, metal organic frameworks (MOFs) embedded in polymer are characterized using differential tomography. MOFs are microporous structures of metal ions, coordinated by organic linker molecules, that can be used in a broad field of applications, especially in gas storage and catalysis. In this work, polymer embedded MOFs were extruded into filaments, which could be used for 3d-printing to profit from the specific properties of the MOFs in polymeric materials combined with the arbitrary shapes provided by 3d-printing. For the extrusion, different polymer classes like ABS, polyester- and polyetherurethanes, as well as different MOFs (ZIF-8, ZIF-67, HKUST-1) were used to create MOF containing filaments with a nominal diameter of 3.0 mm. Differential tomography at the edges of the Zn, Co, and Cu was then used to find the distribution of the corresponding MOF in the filament and to analyze the shape of the inclusions. T2 - MSE 2018 CY - Darmstadt, Germany DA - 26.09.2018 KW - Absorption edge KW - Tomography KW - Metal organic framework KW - Synchrotron PY - 2018 AN - OPUS4-46429 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rades, Steffi A1 - Borghetti, P. A1 - Ortel, Erik A1 - Wirth, Thomas A1 - Blanco, M. A1 - Gómez, E. A1 - Martinez, A. A1 - Jupille, J. A1 - Martra, G. A1 - Hodoroaba, Vasile-Dan T1 - Control of functionalization of supports for subsequent assembly of titania nanoparticle films N2 - For self‐assembling of TiO2 nanoparticles in multiple layers by layer‐by‐layer deposition to be applied to TiO2 thin films with defined and homogeneous thickness for large‐scale applications, the proper functionalization of substrate surface is a prerequisite to guarantee sufficient adhesion. The substrates selected and tested in the present paper were conductive, fluorine‐doped tin oxide (FTO) glass, nonconductive silica glass, and titanium alloy. The current study focusses on the analytical control of the stepwise functionalization of the substrates with 3‐aminopropyltriethoxysilane and glutaraldehyde (GA) for both the FTO glass and silica glass and with 3‐aminepropyl phosphonic acid and GA for Ti alloy. The analyses have been conducted by means of surface sensitive methods, X‐ray photoelectron spectroscopy, Auger electron spectroscopy, and time‐of‐flight secondary ions mass spectrometry. Chemical composition of surface of functionalized substrates shows differences in the degree and type of modification in dependence on substrate. It could be demonstrated that the best functionalized substrates were the conductive FTO glasses. The analysis of the functionalized Ti substrates has revealed that the surface coverage with 3‐aminepropyl phosphonic acid and GA molecules is an inhomogeneous one, and further optimization of the two‐step functionalization on the Ti alloy substrate is necessary. KW - Nanoparticles KW - Surface functionalization KW - TiO2 KW - SEM/EDX KW - Auger Electron Spectroscopy KW - ToF-SIMS KW - Thin films PY - 2018 DO - https://doi.org/10.1002/sia.6398 SN - 0142-2421 SN - 1096-9918 VL - 50 IS - 11 SP - 1200 EP - 1206 PB - John Wiley & Sons, Ltd. AN - OPUS4-46406 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rades, Steffi A1 - Oswald, F. A1 - Narbey, S. A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan T1 - Analytical approach for characterization of morphology and chemistry of a CH3NH3PbI3/TiO2 solar cell layered system N2 - Manufacturing of new perovskite layered solar cells with constant high light conversion Efficiency over time may be hampered by the loss of efficiency caused by structural and/or chemical alterations of the complex layered system. SEM/EDX combined with XPS were chosen as an appropriate methodical approach to characterize perovskite laboratory cells in depth and at surface, before and after light exposure. The layered perovskite system investigated here is based on glass covered with fluorine doped tin oxide, followed by thin films of TiO2, ZrO2, and a thick monolithic carbon. TiO2 film is subdivided into a dense layer covered by porous one constituted of nanoparticles of truncated bipyramidal shape. This layered system serves as the matrix for the perovskite. EDX spectral maps on cross sections of specimen have shown that Pb and I are distributed homogeneously throughout the porous layers C, ZrO2, and TiO2. SEM/EDX data show that 20 weeks of ambient daylight did not change significantly the in‐depth distribution of the elemental composition of Pb and I throughout the entire solar cell system. It was confirmed with EDX that nanoparticles identified in high‐resolution SEM micrographs contain mainly Pb and I, indicating these to be the perovskite crystals. However, a compositional and chemical altering began in the near‐surface region of the outermost ~10 nm after 2 months of illumination which was observed with XPS. T2 - ECASIA 2017 CY - Montpellier, France DA - 24.09.2017 KW - Solar Cell KW - SEM KW - EDX KW - XPS KW - layered system PY - 2018 DO - https://doi.org/10.1002/sia.6410 SN - 0142-2421 SN - 1096-9918 VL - 50 IS - 11 SP - 1234 EP - 1238 PB - John Wiley & Sons, Ltd. AN - OPUS4-46394 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koerdt, Andrea A1 - An, Biwen Annie A1 - Özcan Sandikcioglu, Özlem A1 - Widdel, F. T1 - Microbial corrosion of iron coupled to methanogenesis by strains from different environments N2 - Microbially influenced corrosion (MIC) of iron is usually attributed to sulfate-reducing microorganisms (SRM) which act upon the metal by the reactiveness of hydrogen sulfide, and by withdrawal of the available electrons in electrical contact with the metal. Methanogenic archaea are supposed to cause MIC. Because they do not produce hydrogen sulfide, withdrawal of electrons may be their main corrosive mechanism; however, mechanistic details and kinetics of the overall process are poorly understood. Precipitation of siderite (4Fe + 5HCO3 + 5H+  4FeCO3 + CH4 + 3H2O) can lead to an insulating layer on the metal surface and lower the corrosion rate. Still, the extent of FeCO3 precipitation may be significantly influenced by environmental conditions such as pH and advective processes. T2 - ISME CY - Leipzig, Germany DA - 12.08.2018 KW - Methanogens KW - MIC KW - Corrosion KW - Environmental Simulation PY - 2018 AN - OPUS4-46397 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koerdt, Andrea A1 - An, Biwen Annie A1 - Özcan Sandikcioglu, Özlem A1 - Widdel, F. T1 - Microbial corrosion of iron coupled to methanogenesis by strains from different environments N2 - Microbially influenced corrosion (MIC) of iron is usually attributed to sulfate-reducing microorganisms (SRM) which act upon the metal by the reactiveness of hydrogen sulfide, and by withdrawal of the available electrons in electrical contact with the metal. Methanogenic archaea are supposed to cause MIC. Because they do not produce hydrogen sulfide, withdrawal of electrons may be their main corrosive mechanism; however, mechanistic details and kinetics of the overall process are poorly understood. Precipitation of siderite (4Fe + 5HCO3 + 5H+  4FeCO3 + CH4 + 3H2O) can lead to an insulating layer on the metal surface and lower the corrosion rate. Still, the extent of FeCO3 precipitation may be significantly influenced by environmental conditions such as pH and advective processes. T2 - EMBO-Workshop CY - Vienna, Austria DA - 02.08.2018 KW - Methanogens KW - MIC KW - Corrosion KW - Environmental Simulation PY - 2018 AN - OPUS4-46396 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Hertwig, Andreas A1 - Kormunda, M. A1 - Ryšánek, P. A1 - Ivanov, L. T1 - Characterisation of magnetron sputtered SnZnOx by means of spectroscopic ellipsometry - how can we analyse TCO materials optically? N2 - Transparent conductive oxide (TCO) films are a vital part of a large part of modern technology. The production of TCO materials has sparked much development in plasma coating technology. Quality control measurements of these layers are therefore important in many fields of optics and electronics such as high efficiency thin film photovoltaics. In this presentation, we report on optical measurements of ZnSnOx layers generated by DC/RF magnetron plasma co-sputtering. By changing the respective power on two different targets, the overall power, the gas composition and post-treatment, the properties of this type of layers can be varied in a number of parameters. The optical, electrical, and chemical properties of TCO layers are the technically most important properties together with the layer thickness. The dielectric function of layers is accessible by means of spectroscopic ellipsometry, which also yields the very important value for the layer thickness at the same time. It would be a significant step forward in quality control to use this non-destructive method also as a fast test for electrical properties. Therefore, we report on the optical properties connected to the production parameters, and also on our preliminary results connecting the optical dielectric function (in the visible and near infrared) to the electrical conductivity of the layers. We discuss the effect of deposition parameters on the optical properties of the layers and present an approach for correlating optical and electrical properties. Further, we discuss the question of accuracy of optical properties gained from model-fit-based optical methods and the use of different parameterised models for the dielectric function to achieve this. T2 - PSE 2018 - 16th Conference on Plasma Surface Engineering CY - Garmisch-Partenkirchen, Germany DA - 17.09.2018 KW - Mixed Oxides KW - TCO KW - Quality Control KW - Ellipsometry KW - Optical Constants PY - 2018 AN - OPUS4-46388 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin A1 - Solomun, Tihomir A1 - Sturm, Heinz T1 - Determination of the Microscopic Dose-Damage Relation for Radiation of different Linear Energy Transfer N2 - The determination of the microscopic dose-damage relationship for DNA in an aqueous environment is of a fundamental interest for dosimetry and applications in radiation therapy and protection. We combine geant4 particle-scattering simulations in water with calculations concerning the movement of biomolecules to obtain the energy deposit in the biologically relevant nanoscopic volume.[1] We juxtaposition these results to the experimentally determined damage to obtain the microscopic dose-damage relationship at a molecular level. This approach is tested for an experimentally challenging system concerning the direct irradiation of plasmid DNA (pUC19) in water with electrons as primary particles.[2] Here a microscopic target model for the plasmid DNA based on the relation of lineal energy and radiation quality is used to calculate the effective target volume. It was found that on average fewer than two ionizations within a 7.5-nm radius around the sugar-phosphate backbone are sufficient to cause a single strand break, with a corresponding median lethal energy deposit being E1/2=6±4 eV.[1] The presented method is applicable for ionizing radiation (e.g., γ rays, x rays, and electrons) and a variety of targets, such as DNA, proteins, or cells. [1] Hahn, M. B., Meyer, S., Kunte, H.-J., Solomun, T. & Sturm, H. Measurements and simulations of microscopic damage to DNA in water by 30 keV electrons: A general approach applicable to other radiation sources and biological targets. Phys. Rev. E 95, 052419 (2017). [2] Hahn, M. B. et al. Direct electron irradiation of DNA in a fully aqueous environment. Damage determination in combination with Monte Carlo simulations. Phys. Chem. Chem. Phys. 19, 1798–1805 (2017). T2 - DYSON 2018 CY - Potsdam, Germany DA - 08.10.2018 KW - DNA KW - Dosimetry KW - Electron irradiation KW - Geant4 KW - Hydroxyl radical KW - LET KW - Linear energy transfer KW - Low energy electrons KW - MCS KW - Microdosimetry KW - Monte-Carlo simulations KW - Radiation damage KW - Radiation therapy KW - SEM KW - Electron Microscope KW - LEE KW - Protein PY - 2018 AN - OPUS4-46383 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Emmerling, Franziska T1 - Mechanochemical Syntheses of Metal Phosphonates N2 - Mechanochemistry is a suitable method for synthesizing a variety of metal phosphonates. By varying the ratio of the reactants, it is possible to control the reaction pathway. With this approach targeted synthesis of a certain composition is possible. Several new metal phosphonate structures were solved from the powder X-ray diffraction data including molecular metal phosphonates. The results demonstrate a new fast, facile, and environmental friendly alternative for the preparation of metal phosphonates. In situ investigations of the milling processes provided insights into the formation process of metal phosphonates. A multi-step diffusion mechanism was identified for most systems. Crystalline phases were obtained intermediately, suggesting that the synthesis is following Ostwald’s rules of stages. T2 - 1st European Workshop on Metalphophantes CY - Swanse, UK DA - 18.09.2018 KW - Mechanochemistry PY - 2018 AN - OPUS4-46382 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Riedel, Jens A1 - You, Yi A1 - Bierstedt, Andreas A1 - van Wasen, Sebastian A1 - Bosc-Bierne, Gaby A1 - Weller, Michael G. T1 - Airborne Laser-Induced Plasma as an Ambient Desorption/Ionization Source for Mass Spectrometry and its Characterization N2 - Laser-induced plasma (LIP) has drawn significant amount of attentions in the past decades, particular in elemental analyses for solid or liquid samples. Through proper focusing of the highly energetic laser beam, the plasma can also be ignited in the ambient air, where airborne analytes can be ionized. Such an effect enabled the use of airborne LIP as an ambient ionization source for mass spectrometric analyses. In contrast to other ambient desorption/ionization sources, airborne LIP does not require a specific discharge medium or expensive gas stream. Meanwhile, the airborne LIP produces reagent ion species for both proton-transfer and charge-transfer reactions in addition to the vacuum ultraviolent photons that are capable of promoting single photon ionization, which can be utilized to ionize polar and non-polar analytes. In order to gauge the analytical performance of airborne LIP, it is critical to understand the undergoing chemistry and physics during and after the plasma formation. Due to the ambient nature of airborne LIP, the variations of air composition and flow strongly affect the plasma behaviors. Preliminary result suggested the addition of a laminar flow of nitrogen gas favored the formation of protonated species (MH+) against the molecular ones (M+). Although the gas addition approach cannot fully tune the ionization process towards the specific production of pseudo-molecular species versus molecular ones, the alternation of molecular ion formation can be used for analyte recognitions through post processing of the ion patterns. The pulsed character of the used lasers makes the reagent ion equilibrium both transient- and highly fluid-dynamically controlled. The acoustic shock-waves induced by the airborne LIP get affected by an applied gas streams towards the plasma center, influencing the molecular-ion and ion-ion interactions in the near proximity of the plasma. To understand the airborne LIP formation, the temporally and spatially resolved optical emission spectra were recorded. The results will be correlated to time-resolved mass-spectrometric investigations of the ion profile during different stages of the plasma formation. As one example, the formation of pyrylium ion originating from aromatic compounds will be highlighted. T2 - SciX 2018 CY - Atlanta, GA, USA DA - 21.10.2018 KW - Laser-Induced Plasma KW - Ambient Desorption/Ionization KW - Mass Spectrometry KW - Characterization PY - 2018 AN - OPUS4-46376 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kneipp, Janina A1 - Zhang, Zhiyang T1 - Mapping the Inhomogeneity in Plasmonic Catalysis on Supported Gold Nanoparticles Using Surface-Enhanced Raman Scattering Microspectroscopy N2 - The characterization of a catalyst often occurs by averaging over large areas of the catalyst material. On the other hand, optical probing is easily achieved at a resolution at the micrometer scale, specifically in microspectroscopy. Here, using surface-enhanced Raman scattering (SERS) mapping of larger areas with micrometer-sized spots that contain tens to hundreds of supported gold nanoparticles each, the photoinduced dimerization of p-aminothiophenol (PATP) to 4,4′-dimercaptoazobenzene (DMAB) was monitored. The mapping data reveal an inhomogeneous distribution of catalytic activity in the plasmon-catalyzed reaction in spite of a very homogeneous plasmonic enhancement of the optical signals in SERS. The results lead to the conclusion that only a fraction of the nanostructures may be responsible for a high catalytic activity. The high spot-to-spot variation in catalytic activity is also demonstrated for DMAB formation by the plasmon-catalyzed reduction from p-nitrothiophenol (PNTP) and confirms that an improvement of the accuracy and reproducibility in the characterization of catalytic reactions can be achieved by microspectroscopic probing of many positions. Using SERS micromapping during the incubation of PATP, we demonstrate that the reaction occurs during the incubation process and is influenced by different parameters, leading to the conclusion of dimerization in a gold-catalyzed, nonphotochemical reaction as an alternative to the plasmon-catalyzed process. The results have implications for the future characterization of new catalyst materials as well as for optical sensing using plasmonic materials. KW - P-aminothiophenol KW - Silver nanoparticles KW - Chemical transformation KW - Metal nanoparticles KW - Coupling reactions KW - AU nanoparticle KW - AG nanoparticle KW - Spectroscopy KW - Sers KW - Molecule PY - 2018 DO - https://doi.org/10.1021/acs.analchem.8b01701 VL - 90 IS - 15 SP - 9199 EP - 9205 PB - American Chemical Society AN - OPUS4-46372 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Berger, Achim T1 - Tragbare RFA an Gläsern: Ergebnisse und Grenzen N2 - Vorstellung der Ergebnisse der Messungen an Gläsern von Goethes Prismen. T2 - 3. Goethe/Ritter-Workshop CY - Berlin, Germany DA - 25.05.2018 KW - Goethe KW - Farbenlehre KW - Prisma KW - Handheld KW - XRF PY - 2018 AN - OPUS4-46369 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - de Oliveira Guilherme Buzanich, Ana A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Scharf, o T1 - The colour X-ray camera – Basics and applications of a 2D X-ray detector N2 - The Color X-ray Camera CXC or SLcam® is an energy-resolving X-ray camera capable of energy- and space-resolved measurements. It consists of a high-speed CCD detector coupled to a polycapil-lary optic that conducts the X-ray photons from the probe to distinct pixels onto the detector. The camera is capable of fast acquisition of spatially and energy resolved fluorescence images. A dedicated software enables the acquisition and the online processing of the spectral data for all 69696 pixels, leading to a real-time visualization of the elements distribution in a sample. It was developed in a joint project with BAM, IFG Berlin and PN Sensors. In this contribution we will mainly discuss the use of the CXC at our beamline, the BAMline at BESSY II and imaging applications of the CXC from different areas, like biology and archaeometry. Additionally new developments for the use of the detector without optics, like wavelength dispersive detection or 1shot-XANES, will be presented. T2 - Seminar Strahlenphysikalische Anwendungen in Technik und Medizin CY - ATi Wien, Austria DA - 24.01.2018 KW - XRF KW - Synchrotron KW - BAMline PY - 2018 AN - OPUS4-46365 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mueller, Axel A1 - Eisentraut, Paul A1 - Braun, Ulrike T1 - Nachweis von Mikroplastik in terrestrischen Umweltproben mittels TED-GC-MS N2 - Das Auftreten von Mikroplastik (MP) in aquatischen Ökosystemen ist bereits vielfältig dokumentiert. MP sind Kunststoffpartikel mit einer Größe kleiner als 5000 µm. Sie gelangen entweder als primäres MP (bspw. Zusätze in Kosmetikartikeln) oder als sekundäres MP (Fragmentierung größerer Kunststoffteile) in die Umwelt. Über die Existenz von Kunststoffpartikeln und deren Verbleib in terrestrischen Systemen ist wenig bekannt. Bis heute ist es unklar, ob MP im Boden durch Bodenerosion in die aquatische Umwelt transportiert wird und Boden somit als MP-Quelle für Gewässer fungiert, oder ob Partikel im Boden zurückgehalten werden und Boden eine MP-Senke darstellt. Hierzu sind aussagekräftige Messungen von Proben notwendig. Das Fehlen harmonisierter Verfahren für die Probenahme, Probenaufbereitung und Detektion erschwert die aktuelle Diskussion. In den wenigen bisher veröffentlichten Studien fanden hauptsächlich spektroskopische Methoden wie FTIR- oder Raman-Mikroskopie als Detektionsverfahren Anwendung. Diese liefern in der Regel Aussagen über Partikelanzahlen. Im vorliegenden Projekt soll als Analysemethode die von uns entwickelte ThermoExtraktionDesorption-GasChromatograpie-MassenSpektrometrie (TED-GC-MS) genutzt werden. Bei dieser Methode wird die Probe bis 600 °C erhitzt; die Zersetzungsgase werden auf einer Festphase sorbiert, anschließend in ein GS-MS-System überführt und dort desorbiert, getrennt und identifiziert. Die Methode erlaubt auf schnellem Wege über den Nachweis von spezifischen Zersetzungsprodukten die Identifikation einzelner Polymere, aber auch die quantitative Bestimmung des MP-Massegehaltes in einer Bodenprobe. Ziel des vorliegenden Projektes ist die Entwicklung eines systematischen Protokolls zur Probenahme, Probenaufarbeitung und anschließenden Analyse mittels TED-GC-MS von MP in terrestrischen Proben. Neben der Erstellung einer systematischen Probenahmestrategie sind Probenaufarbeitungsschritte wie die Reduktion der anorganischen Matrix mittels Dichteseparation sowie die oxidative Zersetzung organischer Matrixbestandteile notwendig. Im vorliegenden Tagungsbeitrag präsentieren wir die Anwendung der TED-GC-MS für die Bestimmung von MP in verschiedenen terrestrischen Umweltmatrizen. T2 - Umwelt 2018 CY - Münster, Germany DA - 09.09.2018 KW - TED-GC-MS KW - Mikroplastik KW - Analytik PY - 2018 AN - OPUS4-46364 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Witte, Steffen A1 - de Oliveira Guilherme Buzanich, Ana A1 - Fittschen, U.E.A. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Wobrauschek, P. A1 - Streli, C. T1 - TXRF-XANES: a unique experimental setup for chemical speciation of traces down to pg range N2 - Description of the set-up and first results for TXRF-XANES at BAMline T2 - XAFS 2018 CY - Cracow, Poland DA - 22.07.2018 KW - TXRF KW - XANES KW - Synchrotron KW - BAMline PY - 2018 AN - OPUS4-46363 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Witte, Steffen A1 - Kulow, Anicó A1 - Seeberg, D. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Grunewald, Christian A1 - Riesemeier, Heinrich A1 - Wohlrab, S. T1 - S2XAFS@work: Customization for the Characterization of VOx based Catalysts N2 - X-ray absorption fine structure spectroscopy (XAFS) is a frequently employed technique in order to investigate structural composition and change of chemical compounds such as catalytic species. These structural properties are essential (i) to understand underlying reaction mechanism and (ii) to further improve the design of efficient catalysts. This investigation is based on a newly developed XAFS setup comprising both time- and lateral-resolved XAFS information simultaneously in a single-shot (S2XAFS). The primary broadband beam is generated by a filter/X-ray-mirror combination (bandpass). The transmitted beam through the sample is diffracted by a convexly bent Si (111) crystal, producing a divergent beam. This, in turn, is collected by an area sensitive detector with a theta to 2 theta geometry. This facile, stable and scanningless setup was tested at the BAMline @ BESSY-II (Berlin, Germany). This contribution focuses on further experimental optimizations allowing the characterization of supported vanadium oxide (VOx) based catalysts at the lower hard X-ray regime (5 to 6 keV). First S2XAFS measurements of these catalysts are presented herein. Supported VOx catalysts show promising results in the oxidation of methane to formaldehyde. S2XAFS allows determining the structural composition of the metal (i.e. vanadium) based on a fast and smart setup. It is therefore an ideal tool to identify crucial roles of chemical compounds in catalytic reactions. T2 - XAFS 2018 CY - Cracow, Poland DA - 22.07.2018 KW - XANES KW - XAFS KW - BAMline KW - Synchrotron PY - 2018 AN - OPUS4-46362 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Witte, Steffen A1 - Radtke, Martin A1 - de Oliveira Guilherme Buzanich, Ana A1 - Grunewald, Christian A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Emmerling, Franziska T1 - XAFS@BAMline N2 - X-ray Absorption fine structure spectroscopy (XAFS) is a frequently employed technique in order to investigate structural composition and Change of chemical compounds such as catalytic species or corrosion processes. These structural properties are essential (i) to understand underlying reaction mechanism and (ii) to further improve the design of materials. While XAFS measurements are usually performed with ionization Chambers or simple fluorescence detectors, we at BAMline specialize in measurements with innovative set-ups that meet Specialrequirements such as time resolution, (3D-) spatial Resolution or demanding sample environments. This contribution presents various available XAFS configurations with their corresponding applications. In particular, these comprise single -shot XAFS for time- resolved measurements, grazing-exit XAFS with energy and a spatially resolved detector for the characterization of thin films and an in situ grazing incidence Setup for the characterization of corrosion layers. Additionally,the possibility of analyzing Minute samples in total-reflection geometry is demonstrated. T2 - EXRS 2018 CY - Ljubljana, Slovenia DA - 24.06.2018 KW - XANES KW - XAFS KW - BAMline KW - Synchrotron KW - TXRF PY - 2018 AN - OPUS4-46361 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Breßler, Ingo T1 - SASfit, McSAS and beyond: Prospect of complementary tools for SAS data analysis N2 - Data analysis of SAS measurements has been dominated by the classical curve fitting approach. This method finds optimal parameters of a scattering model composed of analytical expressions. SASfit represents such a classical curve fitting toolbox: it is one of the mature programs for small-angle scattering data analysis and has been available and used for many years. The latest developments [1] will be extended by improving the interoperability of the extensive data base of models with third-party analysis software. An updated format of model definitions is also presented, which allows model function plug-ins to be used with the Python language. To complement the classical curve fitting method, the user-friendly opensource Monte Carlo regression package McSAS was developed. Most importantly, the form-free Monte Carlo approach of McSAS means that it is not necessary to provide any further mathematical restrictions to the Parameter distribution. Future developments include separating the core optimization from the GUI (allowing 'headless' integration), as well as parallel computing which reduces the computing time proportional to the number of available computing cores. The headless mode is presented by an example of Operation within interactive programming environments such as a Jupyter notebook. The promising results of Monte Carlo based data analysis for determining form-free Parameter distributions motivated the evaluation of the method with dynamic light scattering (DLS) data. For this purpose, the method was adapted for analyzing correlation curves such as those from multi-angle dynamic light scattering (DLS) data. The development of McDLS intends to overcome limitations of existing methods at reliably determining the modality of size distributions. An example of Monte Carlo based data analysis of multimodal DLS measurements will be presented. T2 - XVII International Small Angle Scattering Conference - SAS2018 CY - Traverse City, MI, USA DA - 07.10.2018 KW - Data analysis KW - Small angle scattering KW - Dynamic light scattering PY - 2018 AN - OPUS4-46308 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Saloga, Patrick E. J. T1 - SAXS in Analysis of Ultra-small Size-adjustable Zinc Oxide Nanoparticles for Controlled Band Gap Engineering N2 - Zinc oxide (ZnO) as a wide-bandgap II-VI semiconductor finds application in areas like optoelectronics, photocatalysis as well as in detection systems. While band-gap engineering in macroscopic ZnO can be performed by alloying, the band-gap of ZnO nanoparticles is also dependent on their size. Since small-angle X-ray scattering (SAXS) provides a much higher resolution in terms of ultra-small nanoparticle size analysis compared to other techniques, it allows for a careful examination of the correlation between particle size and band-gap. We report on the microwave-assisted synthesis of oleate-capped, photoluminescent zinc oxide nanoparticles with adjustable size as dispersions in organic solvents. The spherical particles were obtained by hydrolysis of the metal precursor in presence of a strong base at temperatures above the solvent’s boiling point. Hence, the reaction is dramatically accelerated and within seconds – instead of hours at lower temperatures –, narrowly dispersed particle systems are yielded. The particles’ sizes as derived from SAXS strongly depend on the reaction temperature and time. Choosing the right reaction conditions, the particle size and thus their band gap can be finely tuned. A size increase can be achieved both by increasing the reaction temperature and the reaction time. See Figure 1 for an exemplary comparison of five-minute syntheses at different temperatures. Here, the yielded particles display diameters between 5.0 and 7.6 nm and corresponding band-gaps of 3.32 up to 3.41 eV. The size increase is accompanied by a red-shift of the UV/Vis absorption edges and fluorescence emission. Furthermore, these particles can be transferred into water by coating with polysorbates. T2 - SAS2018 XVII International Small Angle Scattering Conference CY - Traverse City, Michigan, USA DA - 07.10.2018 KW - SAXS KW - Zinc oxide nanoparticles KW - Microwave synthesis PY - 2018 AN - OPUS4-46348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kormunda, M. A1 - Hertwig, Andreas A1 - Rysanek, P. A1 - Ivanov, L. T1 - Optical and Electrical Properties of reactive/nonreactive Magnetron Deposited SnZnOxCoatings Annealed at Various Temperatures N2 - ZnSnOx coatings were deposited from two 2in magnetron targets made of ZnO and SnO2 connected to DC pulsed and RF power supplies, respectively. The pure Ar and reactive gas mixture Ar/O2 were used. DC pulsed power applied on ZnO target was kept constant 50W 50kHz, 20% d.c. and the RF power applied on SnO2 target was set to values from 0W (pure ZnO deposited) up to 150W (up to 8 at.% of Sn in films). The deposited films were investigated by multiple techniques as deposited at RT as well as after annealing at temperatures 200o C and 450o C. The lower annealing temperature is still compatible with many of common polymeric substrates. The amount of Sn in the films is proportional to applied RF power on SnO2 target. But there is also significant influence of the post Deposition annealing on the film compositions. The ratio Zn/Sn is reduced by the annealing process. Therefore the annealing is promoting the migration of Sn toward the surface and Zn to inside. Moreover the films deposited in oxygen rich reactive gas mixture does not reduces the resistivity with added Sn in contrary to films deposited in Ar where the resistivity was reduced by 5 orders of magnitudes. The plasma parameters were investigated and mean energies of dominant species were in DC pulsed only about 3eV and DC + RF powered plasma up to 15eV. The expected higher energetic particles in the RF influenced plasma deliver an additional energy to the growing film. Therefore, we observed systematic differences between refractive indexes in the films deposited with low RF powered SnO2 magnetron at RT and post-annealed at 200 ° and practically no difference between RT and post-annealed film at higher RF power above 50 W. The XRD results proved the transitions from an amorphous to more crystalline structure by post-annealing of the films. T2 - PSE 2018 - 16th Conference on Plasma Surface Engineering CY - Garmisch-Partenkirchen, Germany DA - 17.09.2018 KW - Reactive sputtering KW - Plasma diagnostics KW - Optical films KW - TCO PY - 2018 AN - OPUS4-46347 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kricheldorf, H. R. A1 - Scheliga, F. A1 - Weidner, Steffen T1 - Cyclic Polyesters via ROPPOC or REP N2 - Various catalysts and polycondensation mechanisms (ROPPOC/REP/ROP)were presented and discussed with regard to the Formation of cyclic and linear polylactides. It could be shown that depending on the structure of the catalyst even- and od numbered cyclics were selectively formed. These data were supported by various analytical techniques like MALDI-TOF mass spectrometry and Size Exclusion Chromatography. T2 - Polycondensation 2018 CY - Alexandria, VA, USA DA - 14.10.2018 KW - Polycondensation KW - MALDI-TOF MS KW - Ring-opening polymerization PY - 2018 AN - OPUS4-46340 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Hielscher, Stefan A1 - Lange, Thorid A1 - Rietz, U. A1 - Lerche, D. T1 - State-of-the-Art in Multiple-Sample Evaluation of Adhesive and Bonding Strength N2 - The paper addresses the “State-of-the-Art in Multiple-Sample Evaluation of Adhesive and Bonding Strength” and the following points are discussed in more detail: 1. Motivation (coatings, varnishes, tapes, laminates, CFRP, adhesive-bonded joints) 2. Conventional single-sample testing (evaluation of adhesive and bonding strength; failure pattern) 3. Multiple-sample handling (MSH), bonding (MSB), and testing: centrifugal adhesion testing (CAT) (multiple-sample approach, tensile test within a centrifuge) 4. Application examples of CAT-Technology™ (laminates, optical coatings, CFRP joints) Finally, a summary is given regarding status quo and benefits of CAT-technology under tensile stress conditions whereas examples of testing in a centrifuge under compressive stress conditions are mentioned in the outlook. T2 - The 5th International Conference Competitive Materials and Technology Processes CY - Miskolc-Lillafüred, Hungary DA - 08.10.2018 KW - Centrifugal Adhesion Testing KW - CAT KW - Multiple-sample handling (MSH) KW - Multiple-sample bonding (MSB) KW - Tensile strength of laminates KW - Tensile strength of coatings KW - Adhesive strength KW - Bonding strength PY - 2018 AN - OPUS4-46336 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haferkamp, Sebastian A1 - Emmerling, Franziska T1 - Mechanochemie N2 - In 3 Minuten sollte das Thema der Dissertation ohne zusätzliche Materialien vorgestellt werden. T2 - FameLab Germany 2018 CY - Potsdam, Germany DA - 15.03.2018 KW - Mechanochemie PY - 2018 AN - OPUS4-46319 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Haferkamp, Sebastian A1 - Akhmetova, Irina A1 - Kulla, Hannes A1 - Rademann, K. A1 - Emmerling, Franziska T1 - Mechanochemical Knoevenagel condensations of benzaldehyde derivates investigated in situ N2 - Mechanochemistry is widely applicable for the synthesis of inorganic, metal-organic, and organic compounds. It is known for short reaction times, nearly quantitative conversions, and decreasing amount of solvents, which opens the field to more environmentally friendly syntheses routes. Among organic syntheses, the Knoevenagel condensation is an important C-C bond forming reaction leading to α,β-unsaturated compounds. To gain more information on the underlying processes, we investigated the syntheses by a combination of different in situ investigation techniques, including synchrotron X-ray diffraction, Raman spectroscopy and thermography. This combination provides information on the structural changes and temperature influences during milling. Benzaldehyde derivates (nitro- and fluoro-derivates) reacted with malononitrile to the respective benzylidenemalononitriles. The in situ investigations show direct and quantitative conversions. In the case of the fluorinated benzaldehyde derivates we showed the possibility of using liquid substrates in mechanochemical organic synthesis. Surprisingly, after crystallization from a viscous state, the material was suitable for single-crystal X-ray analysis. T2 - Powder Diffraction School 2018 CY - Villigen, Switzerland DA - 24.09.2018 KW - C-C coupling KW - Mechanochemistry KW - In situ KW - Knoevenagel PY - 2018 AN - OPUS4-46320 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thünemann, Andreas T1 - Self-healing materials: structure elucidation with SAXS N2 - Healable materials could play an important role in reducing the environmental footprint of our modern technological society through extending the life cycles of consumer products and constructions. Future technologies require smart materials with advanced properties including responsiveness to external stimuli and particularly the ability to autonomously repair inflicted damage. The introduction of reversible connections in the polymer architecture, either in a non-covalent fashion, such as in supramolecular polymers, or by using dynamic covalent chemistry. One facile approach involves the implementation of reversible polymer networks as they offer high mechanical strength and thermal properties that are readily modified by the nature of the connecting dynamic bonds and the crosslinking density. In this context, small-angle scattering allows a detailed insight into the network structure of self-healing polymers either in bulk materials or in form of hydrogels. Here we report on how small-angle scattering can contribute to reveal the network structure. A first example is the conditional repair by locally switching the thermal healing capability of dynamic covalent polymers with light. Typical experimental SAXS curves of a photo- and thermal switchable polymer are shown. The scattering pattern show three characteristics. Region 1 is dominated by a forward scattering interpreted as resultant from large scale inhomogeneities of the bulk polymers (characterized by a first correlation length). The second scattering contribution can be interpreted as resultant from the network and is characterized by its entanglement distance. The mesh size of this network can be described by a second correlation length. Region 3 of the scattering pattern is dominated by a broad peak. Taking all effects into account, we approximate the total scattering as a sum of the three scattering contributions. In particular, the Debye-Büche function is used for I1 the Ornstein-Zernike function for the crosslinking contribution I2 and a Lorentzian peak function. We discussed this simple and more sophisticated approaches for revealing network structures. Examples of studies from hydrogel networks are provided as important materials with polymeric networks in life science applications. Finally, the determination of mesh size distributions as a function of temperature, time and healing efficiency is discussed in detail. T2 - XVII International Small Angle Scattering Conference - SAS2018 CY - Traverse City, Michigan, USA DA - 7.10.2018 KW - Small-angle x-ray scattering KW - Nanomaterial KW - Saxs PY - 2018 AN - OPUS4-46317 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vlajića, M. A1 - Unger, Wolfgang A1 - Bruns, J. A1 - Rueck-Braun, K. T1 - Photoswitching of fulgimides in different environments on silicon surfaces N2 - Reversible light-modulation of fulgimide based monolayers on Si(1 1 1) and Si(1 0 0) was investigated using ATR-FTIR spectroscopy. Fulgimide monolayers were prepared from neat COOH-terminated SAMs on Si(1 1 1) obtained from methyl undec-10-enoate, (1:1)-diluted COOH-terminated monolayers on Si(1 1 1), and GPTMS monolayers on Si(1 0 0). The epoxy-terminated monolayer on oxidized Si(1 0 0) was characterized with ellipsometry, XPS, as well as contact angle measurements, and ATR-FTIR spectroscopy revealed a strong influence of toluene water content on reproducible high-quality monolayer formation. The results of this study show that environmental polarity has a strong influence on fulgimide imide IR band locations and read-out options for the two photostationary states PSS(365 nm), containing E/Z- and C-isomers, and PSS(545 nm), with solely the E/Zisomers. Neat COOH-terminated monolayers on flat Si(1 1 1) have the Advantage of high functional Group concentration, orientation and stability, and an upright arrangement of fulgimide head groups. KW - Surface functionalization KW - Photoswitchable monolayers KW - ATR-FTIR spectroscopy KW - XPS PY - 2019 DO - https://doi.org/10.1016/j.apsusc.2018.09.159 SN - 0169-4332 SN - 1873-5584 VL - 465 SP - 686 EP - 692 PB - Elsevier B.V. AN - OPUS4-46276 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Anja A1 - Saleh, Maysoon I. A1 - Unger, Wolfgang T1 - Investigation of core-shell nanoparticles using a combination of scanning Auger microscopy (SAM) and scanning electron microscopy (SEM) N2 - Products containing engineered nanoparticles already encounter us in most areas of our daily life including cosmetics, clothing, detergents, paints, batteries and displays. In most cases the particles exhibit a core-shell morphology either voluntarily or involuntarily. The properties of the nanoparticle shell determine the interaction with their environment and, thus, reliable control over these properties means reliable control over the particles performance and their toxicity. Therefore, sophisticated techniques to measure thickness and elemental composition of the nanoparticle shell are urgently required. Scanning Auger microscopy (SAM) is a powerful technique with a lateral resolution below 10 nm and a chemical contrast based on the characteristic kinetic energy of Auger electrons related to specific atomic levels and, thus, to a specific element. This work explores the potential of SAM for characterizing the core-shell structure of nanoparticles. A sample system of upconversion NaYF4:Yb,Er cores coated with SiO2 is investigated. Auger spectra, line scans and elemental maps of single nanoparticles will be presented. Challenges encountered will be highlighted, such as damage to the sample by electron beam irradiation. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) are performed on the same samples, in order to verify the SAM results. T2 - BAM PhD Retreat CY - Warnemünde, Germany DA - 28.09.2018 KW - Core-shell nanoparticles KW - SAM KW - SEM KW - Surface analysis PY - 2018 AN - OPUS4-46270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kricheldorf, H. R. A1 - Weidner, Steffen T1 - Cyclic poly(L-lactide)s via simultaneous ROP and polycondensation (ROPPOC) catalyzed by dibutyltin phenoxides N2 - Starting from dibutyltin oxide, four catalysts were synthesized, namely the dibutyltin bisphenoxides of Phenol (SnPh), 4-chlorophenol (SnCP), 4-hydroxybenzonitrile (SnCN) and pentafluorophenol (SnOPF). With the first three catalysts polymerizations of L-lactide at 160 °C in bulk yielded large fraction of linear chains having phenylester end groups at short reaction times. At longer times the fraction of cycles considerably increased at the expense of the linear chains, when SnCN was used as catalyst. With SnOPF only cyclic polylactides were obtained at low Lac/Cat ratios (< 400) with weight average molecular weights (Mw) up to 90 000 Da, whereas for high Lac/Cat ratios mixtures of cyclic and linear chains were found. Polymerizations in solution enabled variation of the molecular weight. Polymerizations of meso-lactide at temperatures down to 60 °C mainly yielded even-numbered linear chains supporting the postulated ROPPOC mechanism. KW - Cyclization KW - MALDI-TOF MS KW - Polycondensation KW - Ring-opening Polymerization KW - Polylactide PY - 2018 DO - https://doi.org/10.1016/j.eurpolymj.2018.10.005 SN - 0014-3057 IS - 109 SP - 360 EP - 366 PB - Elsevier AN - OPUS4-46263 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cant, D. A1 - Shard, A. A1 - Müller, Anja A1 - Clifford, C. A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Surface chemical analysis – Electron spectroscopies – Measurement of the thickness and nature of nanoparticle coatings N2 - Recent years have seen increasing development of nanoparticles for applications in a wide range of fields, including but not limited to areas of great impact such as catalysis, medicine, energy, optoelectronics, cosmetics, and many others. In particular, nanoparticles bearing some form of coating layer, whether by design or due to incidental processes such as contamination or oxidation, are among the most commonly studied and utilised. In the characterisation of nanoparticles, the surface properties are of great importance, because a large proportion of the particle forms a part of the surface or interface. In the case of coated nanoparticles, the thickness of the coating is significant in determining the properties of the nanoparticle, and defines its interactions with its environment. Measurement of surface chemistry and coating thickness of nanoparticles is a challenge to which electron spectroscopies are well suited, due to high surface sensitivity, well-understood physical principles and accessibility. T2 - Annual Meeting of ISO/TC 201/SC7 CY - Cancun, Mexico DA - 21.09.2018 KW - Nanoparticle characterization KW - X-ray Photoelectron Spectroscopy (XPS) KW - Auger Electron Spectroscopy (AES) KW - Core-shell nanoparticles PY - 2018 AN - OPUS4-46259 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Prinz, Carsten A1 - Zimathies, Annett A1 - Emmerling, Franziska T1 - Importance of stability studies on porous certified reference materials N2 - In the development of certified reference materials (CRM), it is necessary to examine appropriate materials in advance for homogeneity and stability to meet the criteria of a CRM. In this case, the materials properties are characterized at the actual time without being possible to give a prognosis for suitability in the following years. It is, therefore, necessary to follow the certified material parameters via a monitoring system over the years on sale. For the current development of CRMs, the gained experience from long-term stability studies about the first generation of porous CRMs is significant. This experience is useful to better assess the suitability of candidate materials and thus develop higher quality CRMs in the future. A comparison between the gas sorption CRM materials silica, activated carbons, alpha alumina and anatase titanium oxides will illustrate the importance of long-term stability studies on porous CRMs. T2 - BERM 2018 - 15th International Symposium on Biological and Environmental Reference Materials CY - Berlin, Germany DA - 23.09.2018 KW - Reference material KW - Monitoring KW - Long-term stability PY - 2018 AN - OPUS4-46257 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Procop, Mathias T1 - Check of the energy-dispersive X-ray spectrometers (EDS) performance with the BAM test material EDS-TM001/2 and BAM software EDS spectrometer test N2 - The test material EDS-TM001 together with an accompanying software package, “EDX spectrometer check”, have been made available in 2009 by BAM to be employed by EDS (energy dispersive spectrometer) users to check the performance of an EDS attached to the SEM. Particularly for test laboratories operating under accreditation schemes like ISO/IEC 17025, a periodical control of the critical instrumental parameters in end-user laboratories is required. With EDS-TM001 or EDS-TM002 (second generation) test material, this periodical check is reduced to the acquisition of only one 10 kV spectrum. The software “EDX spectrometer check” is destined to evaluate automatically this spectrum and determine the performance of the EDS in terms of energy resolution and calibration as well as possible alteration of low-energy efficiency due to detector contamination. Energy resolution can be compared with the specified values according to the international ISO standard ISO 15632:2012. EDS-TM is a synthetic material consisting of a thick layer of C, Al, Mn, Cu and Zr in a well-defined composition, deposited on a steel (in case of EDS-TM001) or silicon (in case of EDS-TM002) substrate. Meanwhile, more than one hundred laboratories (most of them located in Germany) use the EDS-TM001 or EDS-TM002 test material for the periodical check of their EDS. A detailed description of the test material and software together with examples of application was published recently. New results and gained experiences will be presented as well. T2 - BERM-15: International Symposium on Biological and Environmental Reference Materials CY - Berlin, Germany DA - 24.09.2018 KW - EDS KW - SEM/EDX KW - Test material KW - EDS-TM001 KW - EDS-TM002 KW - EDS Spectrometer Test KW - X-rays PY - 2018 AN - OPUS4-46253 LA - eng 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 measurements - Is a liaison to CEN/TC 352 nanotechnologies useful? N2 - The main objectives of the new EMPIR project nPSize are to establish EU capability of traceable measurement of NP size and shape, lower uncertainties of NP size measurement by developement of new nano-CRMs, new models (physical and machine learning), 3D method combination, and also by new ISO and CEN standards on accurate NP size measurement and guidance and knowledge transfer. The envisaged outcomes of the project will be presented and their suitability will be discussed to be taken over as pertinent contributions to normative projects within CEN/TC 352 Nanotechnologies. T2 - Joint Working Groups and 24th CEN/TC 352 Nanotechnologies Meetings CY - DIN, Berlin, Germany DA - 09.10.2018 KW - Nanoparticles KW - Size KW - Particle size distribution KW - Particle shape KW - Traceability KW - Standardisation KW - CEN/TC 352 Nanotechnologies PY - 2018 AN - OPUS4-46252 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan T1 - Overview on the most advanced and suitable NanoDefine measurement methods N2 - The EC Recommendation on the definition of nanomaterial, based solely on size of the constituent particles, foresees development of harmonised measurement methods ensuring ‘consistent results across materials and over time’. The EU/FP7 research project NanoDefine has been exclusively dedicated to support the implementation of this EC Recommendation for the European Union’s legislation. For the first time, measurement techniques able to determine the size of nanoparticles have been evaluated systematically on a well-defined set of quality control materials (spherical, monodisperse) as well as industrial materials of complex shapes and considerable polydispersity. Particularly based on the analytical performance of the measurement techniques as tested on the challenging real-world particulate materials, it was possible to formulate recommendations for use of a new tiered approach consisting of screening and confirmatory techniques. Thus, a consistent framework of guidance for nanomaterial identification according to the EC Definition has been issued in form of the NanoDefiner e-tool, with a transparent decision flow scheme and an extensive user manual. Selected examples of analysis and classification as nano-/non-nanomaterials will be given, highlighting the limits of applicability of the available measurement techniques in dependence on sample properties. On some recent relevant developments in sample preparation – as a crucial part for an accurate analysis - will be also reported. T2 - VCI-NanoDefine Follow-up Meeting CY - VCI, Frankfurt am Main, Germany DA - 25.09.2018 KW - Nanoparticles KW - Nanomaterial KW - EC definition of nanomaterial KW - Nanoparticle size distribution PY - 2018 AN - OPUS4-46251 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heinrich, Thomas A1 - Schneider, Markus A1 - Schäpe, Kaija A1 - Unger, Wolfgang A1 - Stockmann, Jörg M. T1 - Classification of engineered Titania nanomaterials via surface analysis using principal component analysis (PCA) assisted Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) N2 - Due to the growing number of engineered nanomaterials (NM) the need for a reliable risk assessment for these materials is today bigger than ever before. Especially the nanomaterial’s surface or shell directly interacts with its environment and therefore is a crucial factor for NM’ toxicity or functionality. Especially, titania is one of the NM with the greatest technological importance. It is used for a large number of applications and can be found in food, cosmetics, glasses, mirrors, paints to mention only a few. In 2012, experts estimate[d] the annual European nano-titania production or utilization at an amount of more than 10,000 t. Great progress has been achieved in the area of NM investigation and characterization during the past decade. A variety of publications provide information about technological innovation as well as hazard potential, which means the potential risk on human health and ecosystems. However, enhanced data harmonization and well-defined standards for nanomaterial analysis, could significantly improve the reliability of such studies which often suffers from varying methods, parameters and sample preparations. To develop a suitable approach for the NM’s risk assessment, the ACEnano project aims at establishing a toolbox of verified methods. The size of this well-structured European project allows to handle even those big challenges like data harmonization and standardization. Due to its powerful combination of superior surface sensitivity and lateral resolution down to the Nano regime, ToF-SIMS could become one of these toolbox methods. Supported by multivariate data analysis such as principal component analysis (PCA), the method can be used for sub-classification of nanomaterial families using slight differences in surface chemistry. Here, we show a PCA supported classification of titania nanoparticles from various sources (NIST, JRC, BAM) with ToF-SIMS. Parameters like size, shell, pre-preparation and crystal system cause variance in the data and allow us to distinguish the species from each other. Moreover, this variance in the data also occurs and can be used for investigation when we compare our measurements of particle ensembles with those of grown titania films. The carefully selected and refined peaks allow a reasonable particle categorization and further a reliable allocation of blank feeds, which introduces a promising approach for NM characterization in the context of NM risk assessment. T2 - SIMS-Europe CY - Münster, Germany DA - 16.09.2018 KW - Nanoparticles KW - ToF-SIMS KW - XPS KW - PCA KW - Titania PY - 2018 AN - OPUS4-46250 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heinrich, Thomas A1 - Müller, Anja A1 - Schneider, Markus A1 - Sparnacci, Katja A1 - Unger, Wolfgang T1 - Chemical characterisation and classification of (Core-Shell) nanoparticles using PCA assisted ToF-SIMS N2 - The analysis of nanomaterials is currently an important task - especially in case of risk assessment – as the properties of these material class are not well understood and their growing use in everyday life. The rather high surface area of these objects renders their interactions significantly different to their corresponding bulk. Thus, the surface’s chemical composition must be investigated to get a better understanding and prediction of the nanomaterials’ behaviour. ToF-SIMS and XPS have proven to be powerful tools to determine the general chemical composition. The superior surface sensitivity of ToF-SIMS furthermore allows us to study mainly the utmost atomic layers and thus gives us an idea of possible interactions involved. Supported by multivariate data analysis such as principal component analysis (PCA), the method can also be used for sub-classification of different materials using slight differences in surface chemistry. Here, we present data of the analysis of Hyflon®-polystyrene core-shell nanoparticles which can be used as a model system due to the known preparation and a rather good chemical as well as physical separation of core and shell. Principle component analysis (PCA) will be used to detect the influence of sample preparation and for a better separation of different samples. This is achieved by measurement of a statistically relevant set of samples for every particle sample. We acquired surface spectra under static SIMS conditions with Bi32+ and analysed the resulting spectra by PCA. The carefully selected and refined peaks allow a reasonable categorization and further a reliable allocation of blank feeds. In detail, the fluorine containing, organic fragments are an indication for a heterogeneous shell that has errors. Furthermore, results on Au nanoparticles with and without an antibody shell are presented. ToF-SIMS imaging is desired to be implemented for single particle detection as well. T2 - SIMS-Europe CY - Münster, Germany DA - 16.09.2018 KW - Nanoparticles KW - ToF-SIMS KW - XPS KW - PCA KW - Titania KW - Core-Shell PY - 2018 AN - OPUS4-46249 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heinrich, Thomas A1 - Müller, Anja A1 - Unger, Wolfgang T1 - Chemical characterisation of (core-shell) nanoparticles using PCA assisted ToF-SIMS and XPS N2 - The analysis of nanomaterials is currently an important task - especially in case of risk assessment – as the properties of these material class are not well understood. The rather high surface area of these objects renders their interactions significantly different to their corresponding bulk. Thus, the surface’s chemical composition must be investigated to get a better understanding and prediction of the nanomaterials’ behavior. ToF-SIMS and XPS have proven to be powerful tools to determine the general chemical composition. The superior surface sensitivity of ToF-SIMS furthermore allows us to study mainly the utmost atomic layers and thus gives us an idea of the interactions involved. Here, we present initial data on the analysis of Hyflon®-polystyrene core-shell nanoparticles which can be used as a model system due to the known preparation and a rather good chemical as well as physical separation of core and shell. Furthermore, results on Au nanoparticles with and without an antibody shell are presented. Principle component analysis (PCA) will be used to detect the influence of sample preparation and for a better separation of different samples. ToF-SIMS imaging is desired to be implemented for single particle detection as well. T2 - 3rd NanoSafety Forum for Young Scientists CY - Valetta, Malta DA - 08.09.2018 KW - Nanoparticles KW - ToF-SIMS KW - XPS PY - 2018 AN - OPUS4-46248 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grunert, B. A1 - Saatz, Jessica A1 - Hoffmann, Katrin A1 - Appler, F. A1 - Lubjuhn, Dominik A1 - Jakubowski, Norbert A1 - Resch-Genger, Ute A1 - Emmerling, Franziska A1 - Briel, A. T1 - Multifunctional rare-earth element nanocrystals for cell labeling and multimodal imaging N2 - In this work, we describe a simple solvothermal route for the synthesis of Eu3+-doped gadolinium orthovanadate nanocrystals (Eu:GdVO4−PAA) functionalized with poly(acrylic)acid (PAA), that are applicable as cell labeling probes for multimodal cellular imaging. The Eu3+ doping of the vanadate matrix provides optical functionality, due to red photoluminescence after illumination with UV light. The Gd3+ ions of the nanocrystals reduce the T1 relaxation time of surrounding water protons, allowing these nanocrystals to act as a positive MRI contrast agent with a r1 relaxivity of 1.97 mM−1 s−1. Low background levels of Eu3+, Gd3+, and V5+ in biological systems make them an excellent label for elemental microscopy by Laser Ablation (LA)-ICP-MS. Synthesis resulted in polycrystalline nanocrystals with a hydrodynamic diameter of 55 nm and a crystal size of 36.7 nm, which were further characterized by X-ray diffraction (XRD), photoluminescence spectroscopy (PL) and transmission electron microscopy (TEM). The multifunctional nanocrystals were subsequently used for intracellular labeling of both human adipose-derived stem cells (MSCs) and A549 (adenocarcinomic human alveolar basal epithelial) cells. KW - Bioimaging KW - Nanoparticle KW - Multimodal KW - Lanthanide PY - 2018 DO - https://doi.org/10.1021/acsbiomaterials.8b00495 SN - 2373-9878 VL - 4 IS - 10 SP - 3578 EP - 3587 PB - ACS Publications CY - Washington, USA AN - OPUS4-46244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Wolfgang A1 - Kjaervik, Marit T1 - New work item proposal for a technical report for ISO/TC 201 WG 4 “Surface characterization of biomaterials”: Surface chemical analysis – Surface chemical analysis of cells and biofilms N2 - The proposed ISO Technical Report provides a description of a variety of physical methods of analytical chemistry by which bacteria and biofilms can be analysed. The state of the art, sample requirements and strengths associated with each method are identified. T2 - 27th Plenary Meeting of ISO/TC 201 CY - Cancun, Mexico DA - 2018-09-20 KW - Surface chemical analysis of biofilms KW - XPS KW - Fourier-Transform Infrared Spectroscopy KW - 3D nano SIMS KW - Raman-spectroscopy PY - 2018 AN - OPUS4-46214 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nietzold, Carolin A1 - Dietrich, Paul A1 - Holzweber, M. A1 - Lippitz, Andreas A1 - Kamalakumar, A. A1 - Blanchard, V. A1 - Ivanov-Pankov, S. A1 - Weigel, W. A1 - Panne, Ulrich A1 - Unger, Wolfgang T1 - Surface chemical characterization of model glycan surfaces and shelf life studies of glycan microarrays using XPS, NEXAFS spectroscopy, ToF-SIMS and fluorescence scanning N2 - Biomedical applications, including functional biomaterials, carbohydrate-arrays, and glycan-based biosensors. The chemistry of glycan immobilization plays an essential role in the bioavailability and function of surface bound carbohydrate moieties. For biomedical applications the stability over time (shelf life) of glycan arrays is a crucial factor. Herein we report on approaches for surface and interface characterization relevant to the needs of production of glycan microarrays which were tested using model carbohydrate surfaces. For detailed characterization of glycan model surfaces we used a combination of X-ray photoelectron spectroscopy (XPS), near edge X-ray absorption fine structure spectroscopy (NEXAFS) and ToF SIMS which are complementary techniques of surface chemical analysis. Links to fluorescence spectroscopy often used for characterization in the microarray community were established as well. In detail, amine-reactive silicon oxide and glass surfaces were used for anchoring oligosaccharides with an amino linker. The amount of surface bound carbohydrates was estimated by X-ray photoelectron spectroscopy (XPS). Glycan immobilization was investigated using lectins, which are glycan-binding molecules. A shelf life study of model glycan microarrays on epoxy-coated glass surfaces was done over a period of 160 days under different storage conditions utilizing fluorescence, ToF-SIMS and XPS analysis. It was shown that glycan activity of the models used can be maintained at least for half a year of storage at 4 °C. KW - Glycan microarray KW - XPS KW - NEXAFS KW - ToF-SIMS KW - Fluorescence PY - 2018 UR - https://www.sciencedirect.com/science/article/pii/S0169433218320300?via%3Dihub DO - https://doi.org/10.1016/j.apsusc.2018.07.133 SN - 0169-4332 SN - 1873-5584 VL - 459 SP - 860 EP - 873 PB - Elsevier B.V. AN - OPUS4-46212 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Altmann, Korinna A1 - Braun, Ulrike T1 - Reference materials for microplastics in environmental matrices N2 - The pollution of marine, limnic and terrestrial environments with plastic waste and the potential impact especially on biota and humans has received increasing attention in recent years. Special focus is on particles smaller than 5 mm, the so-called microplastics. Consequently, possible regulations of emission and remediation efforts require sound information on the occurrence and fate of microplastics in the respective environmental compartments. Microplastics (MP) differ from classical organic pollutants in biota or the environment in that they do not consist of clearly defined low-molecular weight compounds but of polymer particulates with varying sizes and chemical compositions. This leads to specific challenges regarding the analytical techniques to be employed for their identification and quantification. Microplastics are defined as polymer particle in the size range between 1 µm and 5 mm and cover a wide range of polymers such as polyethylene, polypropylene, polystyrene and polyethylene terephthalate in variable geometric shapes. Properties relevant for environmental microplastics are polymer type, particle form and size distribution, surface morphology (aging status) and total mass fraction contained in a given sample. Polymer identification and particle size estimation using optical methods (IR and Raman spectroscopy) are time consuming and complicated by surface characteristics as a result of weathering, soiling, and microbial colonisation. Total mass fractions of MP in environmental samples can be determined by thermo-analytical methods. There are currently no standardised methods for sampling, sampling preparation, or detection of MP in environmental samples. So far, qualitative and quantitative investigations are done by research institutes and have not reached the routine laboratory community. The near future will see harmonisation efforts of MP mass fraction determination in environmental matrices by thermo-analytical procedures. The immediate need for reference materials during method development and comparison is outlined with regard to relevant matrix/polymer compositions, existing regulations and currently achievable detection limits. Examples for solid environmental matrix reference materials are discussed regarding the challenges encountered with matrices and polymer types as well as homogeneity testing and property value characterisation. T2 - BERM 2018 15th International Symposium on Biological and Environmental Reference Materials CY - Berlin, Germany DA - 23 September 2018 KW - Referenzmaterialien KW - Schwebstoffe KW - Sediment KW - Polymer PY - 2018 AN - OPUS4-46209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wanner, C. A1 - Poethig, R. A1 - Carrero, S. A1 - Fernandez-Martinez, A. A1 - Jäger, Christian A1 - Furrer, G. T1 - Natural occurrence of nanocrystalline Al-hydroxysulfates: Insights on formation, Al solubility control and As retention N2 - Nanocrystalline basaluminite [Al4OH10(SO4)(H2O)3–5] and Aggregation of the e-Keggin polyoxocation [Al12(AlO4)(OH)24(H2O)12]7+, referred to as Al13, have both been described to form in acid mine Drainage environments. Although the chemical composition is quite similar, their crystalline varieties significantly differ, demonstrating that various types of Al-hydroxysulfates can form under similar conditions and that their respective formation is not fully understood yet. Here, we report the occurrence of nanocrystalline precipitates that form naturally in a small alpine catchment in Switzerland where an acidic mountainous stream (pH 4) is neutralized successively after mixing with several neutral tributaries. The stepwise neutralization in conjunction with the large amount of precipitates provide an ideal setting for obtaining new insights into (i) the structure of naturally forming Al-hydroxysulfates, (ii) their formation mechanism, (iii) their role in controlling the solubility of Al, and (iv) their ability to lower the mobility of As. Synchrotron-based high-energy X-ray diffraction and subsequent pair distribution function analyses demonstrate that these precipitates are structurally identical to basaluminite samples obtained from acid mine drainage sites. In contrast, only minor amounts of tetrahedrally coordinated Al, as present in Al13, were identified by nuclear magnetic resonance spectroscopy. The precipitates are further characterized by elevated As concentrations up to 600 lg/g, whereas other heavy metals are at background concentrations only. Given the low As concentrations in the stream from which precipitation occurs (<0.03 mg/L), high As concentrations confirm that basaluminite serves as a highly efficient As sink, which is attributed to its high anion-exchange capacity. Chemical analysis of streamwater samples in combination with geochemical modeling show that precipitation occurs instantaneously upon mixing with neutral streams. Moreover, our data reveal that the precipitation of basaluminite exerts a strong solubility control on dissolved Al concentrations as manifested by the quasi-constant basaluminite ion activity product observed during neutralization from pH 5 to pH 5.9. We hypothesize that in our field system, high fluoride and sulfate concentrations on the order of 100 and 1–2 mg/L, KW - Basaluminite KW - Al13 KW - Acid rock drainage KW - Arsenic retention KW - Aluminum KW - Anion exchange PY - 2018 DO - https://doi.org/10.1016/j.gca.2018.06.031 SN - 0016-7037 SN - 1872-9533 VL - 238 SP - 252 EP - 269 PB - Elsevier Ltd. AN - OPUS4-46164 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mino, L. A1 - Pellegrino, F. A1 - Rades, Steffi A1 - Radnik, Jörg A1 - Hodoroaba, Vasile-Dan A1 - Spotto, G. A1 - Maurino, V. A1 - Martra, G. T1 - Beyond shape engineering of TiO2 nanoparticles: Post-synthesis treatment dependence of surface hydration, hydroxylation, Lewis acidity and photocatalytic activity of TiO2 anatase nanoparticles with dominant {001} or {101} facets N2 - TiO2 anatase nanoparticles are among the relevant players in the field of light-responsive semiconductor nanomaterials used to face environmental and energy issues. In particular, shape-engineered TiO2 anatase nanosheets with dominant {001} basal facets gained momentum because of the possibility to exploit different and/or improved functional behaviors with respect to usual bipyramidal TiO2 anatase nanoparticles, mainly exposing {101} facets. Nevertheless, such behavior depends in a significant extent on the physicochemical features of surfaces exposed by nanosheets. They can vary in dependence on the presence or removal degree of capping agents, namely, fluorides, used for shape-engineering, and experimental investigations in this respect are still a few. Here we report on the evolution of interfacial/ surface features of TiO2 anatase nanosheets with dominant {001} facets from pristine nanoparticles fluorinated both in the bulk and at their surface to nanoparticles with F− free surfaces by treatment in a basic solution and to totally F− free nanoparticles by calcination at 873 K. The nanoparticles fluorine content and its subsequent evolution is determined by complementary techniques (ion chromatography, TOF-SIMS, XPS, AES, SEM-EDX), probing different depths. In parallel, the evolution of the electronic properties and the Ti valence state is monitored by UV−vis spectroscopy and XPS. The calcination treatment results in {001} facets poorly hydroxylated, hydrated, and hydrophilic, which appear as surface features consequent to the expected (1 × 4) reconstruction. Moreover, IR spectroscopy of CO adsorbed as probe molecule indicates that the Lewis acidity of Ti4+ sites exposed on (1 × 4) reconstructed {001} facets of calcined TiO2 nanosheets is weaker than that of cationic centers on {101} facets of bipyramidal TiO2 anatase nanoparticles. The samples have also been tested in phenol photodegradation highlighting that differences in surface hydration, hydroxylation, and Lewis acidity between TiO2 nanoparticles with nanosheet (freed by F− by calcination at 873 K) and bipyramidal shape have a strong impact on the photocatalytic activity that is found to be quite limited for the nanoparticles mainly exposing (1 × 4) reconstructed {001} facets. KW - Nanoparticles KW - TiO2 KW - F- doping KW - Shape-controlled nanoparticles KW - Nanosheets PY - 2018 DO - https://doi.org/10.1021/acsanm.8b01477 SN - 2574-0970 VL - 1 IS - 9 SP - 5355 EP - 5365 PB - ACS Publications CY - Washington, DC, U.S.A. AN - OPUS4-46157 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kjaervik, Marit A1 - Dietrich, P. A1 - Thissen, A. A1 - Schwibbert, Karin A1 - Unger, Wolfgang T1 - Investigations of biofilms in various conditions by near-ambient pressure XPS N2 - X-ray photoelectron spectroscopy (XPS) provides elemental and chemical information from the outermost ~10 nm of the sample surface. This is in the same order of magnitude as the thickness of the outer bacterial membrane of gram-negative bacteria, as well as outer membrane molecules as exopolysaccharides and lipopolysaccharides, commonly attached to the cell surface. With the development of near-ambient pressure (NAP)-XPS, bacteria can be analysed with minimal sample preparation. EnviroESCA is a laboratory based NAP-XPS instrument, equipped with a monochromated Al Kα radiation source and a differentially pumped energy analyser connected to an exchangeable sample environment. It allows for measurements in various gas-atmospheres, including water vapor, which makes it possible to characterise bacteria and other biological samples close to their natural, hydrated state. Artificial model-biofilms of exopolysaccharides, planktonic Pseudomonas Fluorescens and biofilms of Escherichia Coli have been characterised in hydrated and dried state. High-resolution XPS-spectra from carbon, oxygen, nitrogen and phosphorous can be assigned to carbohydrates, lipids and proteins in general agreement with literature. Especially the carbon 1s peak is of interest. A series of measurements of an E. coli biofilm from 11 mbar in humid environment to 1 mbar air reveal changes in the C1s peak, which suggests that the bacterial surface undergo substantial Change. T2 - BAM PhD-retreat CY - Warnemünde, Germany DA - 28.09.2018 KW - Biofilms KW - E. coli KW - NAP-XPS PY - 2018 AN - OPUS4-46132 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maiwald, Michael A1 - Emmerling, Franziska A1 - Villajos Collado, José Antonio A1 - Maierhofer, Christiane A1 - Thiel, Erik A1 - Altenburg, Simon T1 - Already producing or still assembling? – Perspectives towards modular production and quality control in a digitized process industry N2 - The CLEAN ENERGY Flagship is an initiative designed to utilize recent game changing developments in digital, materials and manufacturing technologies to catalyze a radical paradigm shift towards clean, reliable, efficient and cost-optimal energy. Unifying and drastically accelerating radically new energy material design, processing and integration across the entire value chain addressing energy production, conversion, storage and systems. CLEAN ENERGY participants are all distinguished research organisations that each benefit from their own industry networks and contacts with regions and state-level activities and have a long history of collaborating with each other (for 10 years now under the umbrella of EERA) within a European collaborative framework. Through EERA, CLEAN ENERGY aims to become a crucial partner in the SET-Plan, supporting long-lasting approaches through its established networks and internal collaborations. T2 - Clean Energy Workshop on Autonomous Materials Development Platforms CY - Brussels, Belgium DA - 02.10.2018 KW - Digitization KW - Energy production KW - Energy storage KW - Energy systems KW - Clean energy technology PY - 2018 AN - OPUS4-46135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pauw, Brian Richard A1 - Breßler, Ingo A1 - Snow, T. A1 - Thünemann, Andreas T1 - Software- and instrument development for characterization of nano-(C)RMs N2 - This poster deals with improvements and characteriztion of small-angle scattering limitations, by looking at the trifecta of Data collection and uncertainty propagation, data analysis methodologies, and real-world tests. It is found that - with appropriate care and instrumentation - accuracies of 1% on mean nanomaterial sizes, and 10% on the size distribution width as well as the volume fraction can be achieved. T2 - BAM-PTB Workshop on Reference Nanomaterials CY - Berlin, Germany DA - 14.05.2018 KW - Small-angle scattering KW - Instrumentation KW - Methodology KW - MAUS KW - Data analysis KW - Data correction PY - 2018 AN - OPUS4-46107 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Kirner, Sabrina V. A1 - Wirth, Thomas A1 - Spaltmann, Dirk A1 - Krüger, Jörg T1 - Chemical effects in the formation of fs-laser-induced periodic surface structures N2 - The processing of laser-induced periodic surface structures (LIPSS, ripples) on metals and semiconductors in ambient air is usually accompanied by superficial oxidation effects - widely neglected in the current literature. In this contribution, chemical, structural, and mechanical alterations in the formation of femtosecond LIPSS are characterized by a variety of surface analytical techniques, including energy dispersive X-ray analyses (EDX), X-ray photoelectron spectroscopy (XPS), micro Raman spectroscopy (µ-RS), and depth-profiling Auger electron microscopy (AEM). Alternative routes of electrochemical and thermal oxidation allow to qualify the relevance of superficial oxidation effects on the tribological performance in oil lubricated reciprocating sliding tribological tests (RSTT). It is revealed that the fs-laser processing of near-wavelength sized LIPSS on metals leads to the formation of a few hundreds of nanometer thick graded oxide layer, consisting mainly of amorphous oxides. Regardless of its reduced hardness and limited thickness, this nanostructured surface layer can effciently prevent a direct metal-metal contact in the RSTT and may also act as an anchor layer for specific wear-reducing additives contained in the engine oil involved T2 - 8th International LIPSS Workshop CY - Bochum, Germany DA - 27.09.2018 KW - Laser-induced periodic surface structures, LIPSS KW - Femtosecond KW - Oxidation KW - Tribology PY - 2018 AN - OPUS4-46106 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bonse, Jörn A1 - Legall, Herbert A1 - Schwanke, Christoph A1 - Pentzien, Simone A1 - Krüger, Jörg T1 - X-ray emission during processing of metals with ultrashort laser pulses N2 - Ultrashort laser pulse micromachining features a high precision. By increasing the repetition rate of the applied laser to several 100 kHz, laser processing becomes quick and cost-effective and make this method attractive for industrial applications. Upon exceeding a critical laser intensity, hard X-ray radiation is generated as a side effect. Even if the emitted X-ray dose per pulse is low, the accumulated X-ray dose becomes significant for high-repetition-rate laser systems so that radiation safety must be considered. T2 - 8th International LIPSS Workshop CY - Bochum, Germany DA - 27.09.2018 KW - X-ray KW - Laser processing KW - Ultrashort KW - Metals PY - 2018 AN - OPUS4-46104 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hollamby, M. J. A1 - Holmes, A. T. A1 - Blackburn, E. A1 - Danks, A. A1 - Jellyman, E. A1 - Pauw, Brian Richard A1 - Rogers, S. A1 - Grillo, I. A1 - Saeki, A. A1 - Nakanishi, T. T1 - Formation and magnetic alignment of a photoconductive organogel formed by an alkyl-C60 hydrophobic amphiphile N2 - The formation and alignment of gel fibres in alkanes (solvents) was investigated. The gel fibres consist of small amphiphilic molecules containing a C60 molecule and a small ligand chain. Under the right conditions, these self-assemble in core-shell micelles, which themselves pack into micron-sized fibre-like structures. These can be aligned using a strong magnetic field, as investigated using SANS with a 17T superconducting magnet at a range of field strengths. T2 - 7th EuCheMS Chemistry Congress CY - Liverpool, UK DA - 26.08.2018 KW - Small-angle scattering KW - Alignment KW - SANS KW - SAXS PY - 2018 AN - OPUS4-46101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg T1 - Ultrakurze Laserimpulse in der Materialbearbeitung: Anwendungen und Sicherheitsaspekte N2 - Im Überblicksvortrag werden Untersuchungen zur Laser-Mikro- und Nanostrukturierung mit Femtosekunden-Laserimpulsen und ausgewählte Anwendungen, z.B. in der Photovoltaik und Biomedizin, vorgestellt. Aktuelle Fragestellungen zur sicheren Prozessführung, wie die mögliche Erzeugung von Röntgenstrahlung beim Laserbearbeitungsprozess und unerwünschte Partikelemissionen, werden aufgegriffen. T2 - Laserverbund Berlin Brandenburg, 89. Laserstammtisch Berlin Brandenburg - Laser für die Materialbearbeitung CY - Berlin, Germany DA - 17.09.2018 KW - Lasermikrobearbeitung KW - Femtosekundenlaser KW - Photovoltaik KW - Biomedizin KW - Lasersicherheit KW - Röntgenemission PY - 2018 AN - OPUS4-46077 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg T1 - Femtosecond laser micromachining N2 - The presentation reviews femtosecond laser ablation experiments on metals, semiconductors, dielectrics, and biological materials. T2 - 19th Erwin Schrödinger Colloquium CY - Vienna, Austria DA - 24.09.2018 KW - Laser ablation KW - Laser micromachining KW - Femtosecond laser KW - Ultrashort pulse laser PY - 2018 AN - OPUS4-46075 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wintzheimer, S. A1 - Szczerba, Wojciech A1 - de Oliveira Guilherme Buzanich, Ana A1 - Kashiwaya, S. A1 - Klein, A. A1 - Jaegermann, W. A1 - Toupance, T. A1 - Shmeliov, A. A1 - Nicolosi, V. A1 - Heuzé, K. A1 - Mandel, K. A1 - Dembski, S. T1 - Discovering the determining parameters for the photocatalytic activity of TiO2 colloids based on an anomalous dependence on the specific surface area N2 - The photocatalytic (PC) performance of titanium dioxide (TiO2) nanoparticles strongly depends on their specific surface, the presence of crystal defects, their crystal phase, and the exposed crystal facets. In order to understand which of these factors contributes most significantly to the PC activity of TiO2 colloids, all of them have to be individually analyzed. This study entails the synthesis of five anatase nanocrystal samples. By maintaining the same reactant ratios as well as hydrothermal sol–gel synthesis route and only varying the autoclaving time or temperature, different crystallite sizes are obtained under comparable experimental conditions. A decrease in PC performance with increase in specific surface area is found. Such an unexpected counterintuitive result establishes the basis for a better understanding of the crucial factors that ultimately determine the PC activity. These are investigated by studying nanocrystals bulk and surface structure and morphology using a selection of complementary analysis methods (X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure (XAFS), X-ray diffraction (XRD)…). It is found that a change in the nanocrystal morphology from an equilibrium state truncated tetragonal bipyramid to a more elongated rod-like structure accompanied by an increase in oxygen vacancies is responsible for an augmented PC activity of the TiO2 nanocrystals. KW - Ti-based colloids KW - Photocatalysis KW - Spectroscopy KW - XAFS PY - 2018 DO - https://doi.org/10.1002/ppsc.201800216 SN - 0934-0866 SN - 1521-4117 VL - 35 IS - 9 SP - 1800216, 1 EP - 10 PB - Wiley Online Library AN - OPUS4-46068 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 - About formation of cycles in Sn(II) octanoate-catalyzed polymerizations of lactides N2 - At first, formation of cycles in commercial poly(Llactide)s is discussed and compared with benzyl alcoholinitiated polymerizations performed in this work. This comparison was extended to polymerizations initiated with 4-cyanophenol and pentafluorothiophenol which yielded cyclic polylactides via end-biting. The initiator/catalyst ratio and the acidity of the initiator were found to be decisive for the extent of cyclization. Further polymerizations of L-lactide were performed with various diphenols as initiators/co-catalysts. With most diphenols, cyclic polylactides were the main reaction products. Yet, only catechols yielded even-numbered cycles as main reaction products, a result which proves that their combination with SnOct2 catalyzed a ring-expansion polymerization (REP). The influence of temperature, time, co-catalyst, and catalyst concentrations was studied. Four different transesterification reactions yielding cycles were identified. For the cyclic poly(L-lactide)s weight average molecular weights (Mw’s) up to 120,000 were obtained, but 1H NMR end group analyses indicated that the extent of cyclization was slightly below 100%. The influence of various parameters like structure of Initiator and catalyst and temperature on the formation of cyclic poly(Llactide)s has been investigated. Depending on the chosen conditions, the course of the polymerization can be varied from a process yielding exclusively linear polylactides to mainly cyclic polylactides. Three different reaction pathways for cyclization reactions have been identified. KW - Cyclization KW - MALDI-TOF MS KW - Polyester KW - Ring-opening polymerization KW - Transesterification PY - 2018 DO - https://doi.org/10.1002/pola.29077 SN - 0887-624X VL - 56 IS - 17 SP - 1915 EP - 1925 PB - Wiley Periodicals Inc. AN - OPUS4-46052 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Thünemann, Andreas T1 - Characterization of (bio)macromolecules and polymeric materials with modern scattering methods N2 - The analysis of polymers, biopolymers and polymeric materials is of great interest in biomaterials science. Here small-angle x-ray scattering (SAXS), static light scatterin (SLS) and dynamic light scattering (DLS) are described. Current efforts for digitalization of this methods are explaind with respect to modern data science in biomedical research. T2 - MacroBio Summer School 2018: Biomaterial Science in View of Digitalization CY - Teltow, Germany DA - 24.09.2018 KW - Small-angle x-ray scattering KW - SAXS KW - Static light scattering KW - SLS KW - Dynamic light scattering KW - DLS KW - Biomaterials PY - 2018 AN - OPUS4-46051 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Röhsler, Andreas A1 - Sobol, Oded A1 - Nolze, Gert A1 - Böllinghaus, Thomas A1 - Unger, Wolfgang T1 - Analysis of deuterium in austenitic stainless steel AISI 304L by Time-of-Flight Secondary Ion Mass Spectrometry N2 - Due to their excellent combination of ductility, strength and corrosive resistance, austenitic stainless steels (ASS) are widely used in many industrial applications. Thus, these steel grades can be found as structural components in the (petro-)chemical industry, in offshore applications and more recent for storage and transport of hydrogen fuel. Steels employed for these applications are exposed to aggressive environments and hydrogen containing media. The ingress and accumulation of hydrogen into the microstructure is commonly observed during service leading to a phenomenon called “hydrogen embrittlement”. A loss in ductility and strength, the formation of cracks and phase transformations are typical features of this hydrogen-induced degradation of mechanical properties. Although, great efforts are made to understanding hydrogen embrittlement, there is an ongoing debate of the underlying mechanisms. This knowledge is crucial for the safe use and durability of components on the one side and the development of new materials on the other. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was proven to be a powerful tool for depicting the distribution of the hydrogen isotope deuterium in the microstructure of austenitic and duplex steels. The combination with imaging techniques such as electron backscatter diffraction (EBSD) and scanning electron microscopy (SEM), delivering structural and morphological information, creates a comprehensive picture of the hydrogen/deuterium-induced effects in the materials. All the gathered data is treated with principal component analysis (PCA) and data fusion to enhance the depth of information. The mobility of hydrogen and deuterium in a steel microstructure is affected by external mechanical stress. To investigate the behaviour of deuterium in a strained microstructure, a new in situ experimental approach was developed. This gives the possibility of analysing samples in the SIMS instrument simultaneously to four-point-bending-tests. Specimens made from ASS AISI 304L were electrochemically charged with deuterium instead of hydrogen. This necessity stems from the difficulty to separate between artificially charged hydrogen and hydrogen existing in the pristine material or adsorbed from the rest gas in the analysis chamber. Nonetheless, similar diffusion, permeation and solubility data allow to draw qualitative conclusions from the experiments, which are relevant for the application addressed. T2 - SIMS Europe 2018 CY - Münster, Germany DA - 16.09.2018 KW - Hydrogen KW - Deuterium KW - Austenitic stainless steel KW - SIMS PY - 2018 AN - OPUS4-46029 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhmert, L. A1 - Sieg, H. A1 - Braeuning, A. A1 - Lampen, A. A1 - Thünemann, Andreas A1 - Kästner, Claudia T1 - Fluorescence labeling study of silver nanoparticles N2 - During the last years, there has been a rapid rise in the use of nanomaterials in consumer products. Especially silver nanoparticles are frequently used because of their well-known optical and antimicrobial properties. However, the toxicological studies focusing on silver nanoparticles are controversial, either claiming or denying a specific nano-efffect. To contribute to localizing nanoparticles in toxicological studies and to investigate the interaction of particles with cells, a fluorescent marker is often used to monitor their transport and possible degradation. A major problem, in this context is the issue of binding stability of a fluorescent marker which is attached to the particle. In order to overcome this problem we provide an investigation of the binding properties of fluorescence-labeled BSA to small silver nanoparticles. Therefore, we synthesized small silver nanoparticles which are stabilized by poly(acrylic acid). The particles are available as reference candidate material and were thoroughly characterized in an earlier study. The ligand was exchanged by fluorescence marked albumin (BSA-FITC). The adsorption of the ligands was monitored by dynamic light scattering (DLS). To verify that the observed effects on the hydrodynamic radius originate from the successful ligand exchange and not from agglomeration or aggregation we used small angle X-ray scattering (SAXS). The fluorescent particles were characterized by UV/Vis and fluorescence spectroscopy. Afterwards, desorption of the ligand BSA-FITC was monitored by fluorescence spectroscopy and the uptake of particles in different in vitro models was studied. The particles are spherical and show no sign of aggregation after successful ligand exchange. The fluorescence intensity is quenched significantly by the presence of the silver cores as expected, but the remaining fluorescence intensity was high enough to use these particles in biological investigations. Half-life of fluorescence labeling on the particle was 21 d in a highly concentrated solution of non-labeled BSA. Thus, a very high dilution and long incubation times are needed to remove BSA-FITC from the particles. Finally, the fluorescence-labeled silver nanoparticles were used for uptake studies in human liver and intestinal cells, showing a high uptake for HepG2 liver cells and almost no uptake in differentiated intestinal Caco-2 cells. In conclusion, we showed production of fluorescence-marked silver nanoparticles. The fluorescence marker is strongly adsorbed to the silver surface which is crucial for future investigations in biological matrices. This is necessary for a successful investigation of the toxicological potential of silver nanoparticles. T2 - NanoTox 2018 - 9th International Conference on Nanotoxicology CY - Neuss, Germany DA - 18.09.2018 KW - Silver nanoparticles KW - Fluorescence KW - Cell imaging KW - Dynamic light scattering PY - 2018 AN - OPUS4-45639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Hidde, Gundula A1 - Lange, Thorid A1 - Gargouri, H. A1 - Kärkkänen, I. A1 - Naumann, F. T1 - Plasma Activation and Plasma-assisted ALD Surface Modification of Polymers for Improved Bonding and Adhesive Strength N2 - Bonding strength is crucial on polymers of low surface energy, for clean surfaces limited to 0.5, 1, and 2 MPa for PTFE, PP, and PE. Plasma treatment may improve bonding strength by a factor of 2 (PTFE) or 5 (PP and PE). The efficiency of treatment is usually 10% as both low pressure and atmospheric pressure processes show low topographic conformity. Besides, lifetime of activation/modification is rather short. Hence, bonding has to be carried out immediately after plasma treatment. The concept of plasma-assisted ALD (atomic layer deposition) interlayers was introduced in the project HARFE of SENTECH (modification/deposition/in-situ monitoring) and BAM (bonding, characterization, testing). ALD deposition has a high surface conformity and for dielectric films of Al2O3 also a good long-term stability given that the films are dense enough. Based on TMA and O2/O3 precursors, ALD layer stacks from 60 to 375 monolayers were prepared under different conditions. For a transfer time of 24 hours from deposition to measurement, bonding strength could be increased up to 5 MPa (PTFE) respectively 10 MPa (PP, PE). The huge potential of ALD layers as adhesive interlayers was demonstrated for Al2O3 on stainless steel with bonding strength beyond 15 MPa, i.e. interface strength within the ALD stack is also in this range. This is a prerequisite for subsequent PVD/CVD-deposition in hybrid systems. By means of the SI ALD LL system of SENTECH thermal and plasma-supported ALD processes can be alternatively realized. Ellipsometric in-situ monitoring provides monolayer sensitivity and reveals that the efficient bonding of the lower ALD layers on the polymer has to be further improved. Testing of bonding strength was realized by CAT (centrifugal adhesion testing) technology. It was shown that ALD modification correlates with the increase of surface energy and bonding strength. T2 - PSE 2018 - 16th Conference on Plasma Surface Engineering CY - Garmisch-Partenkirchen, Germany DA - 17.09.2018 KW - Plasma activation KW - Plasma-assisted ALD modification KW - Adhesive ALD interlayer KW - Bonding strength KW - Adhesive strength PY - 2018 AN - OPUS4-46015 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rietz, U. A1 - Lerche, D. A1 - Hielscher, Stefan A1 - Grunwald, Daniel A1 - Beck, Uwe T1 - Determination of coating properties by using analytical centrifugation N2 - The majority of all products have coated surfaces designed to fulfil different requirements. Building constructions are exposed to external influences like a wide temperature and humidity range, rain and UV radiation to name a few. The extension of machine life for metal cutting tools, like drills or milling cutters is another field of application for coated surfaces. The surfaces have to be modified in a way to maintain their specific functionality. Although adhesion testing of coatings is of great interest, it is still a challenge to obtain reliable quantitative results and to meet economic requirements. In this talk we deal with the curing behaviour of different 2-component epoxy paint systems for corrosion protection of metal constructions. After preparation of specimens the strength was determined in specified time intervals during curing. It could be shown that epoxy paints differ significantly on curing time as well as final strength. The second experimental study deals with coating systems on glass fibre reinforced plastics which are used for wind power turbines to reduce abrasive wear and ice adhesion for aerodynamic and safety reasons. All measurements have been carried out by CAT-TechnologyTM (Centrifugal Adhesion Testing), which uses the radially directed centrifugal force as test-load. The multi-sample test instrument analyses up to eight test specimen under identical testing conditions. By varying the rotational speed (100 rpm up to 13,000 rpm), forces from 0.1 N to 6.5 kN are applied. Upon reaching the critical rupture force, the stamp separates from the substrate and a sample related IR-signal is sent from the spinning rotor. For each test specimen breaking force is calculated and displayed in real-time. The innovative measurement principle meets the requirements of DIN EN 15870 and ISO 4624. T2 - EURADH 2018 CY - Lisbon, Portugal DA - 05.07.2018 KW - Adhesive strength determination KW - CAT-technology KW - Centrifugal adhesion testing KW - Metal coatings KW - Decorative coatings on polymer substrates PY - 2018 AN - OPUS4-46001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Terborg, R. A1 - Procop, Mathias T1 - Check of the performance of EDS systems attached to the SEM with the test material EDS-TM001/2 and evaluation software package EDS spectrometer test - Application, experiences and updates N2 - The test material EDS-TM001 together with an accompanying software package, “EDX spectrometer check”, have been made available in 2009 by BAM to be employed by EDS (energy dispersive spectrometer) users to check the performance of an EDS attached to the SEM. Particularly for test laboratories operating under accreditation schemes like ISO/IEC 17025, a periodical control of the critical instrumental parameters in end-user laboratories is required. With EDS-TM001 or EDS-TM002 (second generation) test material, this periodical check is simplified to the acquisition of only one 10 kV spectrum. The software “EDX spectrometer check” is destined to evaluate automatically this spectrum and determine the performance of the EDS in terms of energy resolution and calibration as well as possible alteration of low-energy efficiency due to detector contamination. Energy resolution can be compared with the specified values according to the international ISO standard ISO 15632:2012. EDS-TM is a synthetic material consisting of a thick layer of C, Al, Mn, Cu and Zr in a well-defined composition, deposited on a steel (in case of EDS-TM001) or silicon (in case of EDS-TM002) substrate. Meanwhile, more than one hundred laboratories use the EDS-TM001 or EDS-TM002 test material for the periodical check of their EDS. A detailed description of the test material and software together with examples of application was published recently. New results and gained experiences will be presented as well. When the FWHM of lines appearing in the EDS-TM spectrum are determined, the spectrum background must be subtracted accurately. The applied physical background subtraction procedure is robust and takes into account the transmission of the detector window. While the previous version considers only Moxtek AP windows, the new version includes selection of silicon nitride window and the case of windowless detector. Moreover, the new version allows importing of spectra in Bruker spx format and EMSA/MSA files from EDAX TEAM software. KW - EDS KW - Performance check KW - SEM KW - Test material KW - X-ray spectrometer PY - 2018 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/check-of-the-performance-of-eds-systems-attached-to-the-sem-with-the-test-material-edstm0012-and-evaluation-software-package-eds-spectrometer-test-application-experiences-and-updates/3D01FDC765C3ECD734CB8DEC7081DAE2 DO - https://doi.org/10.1017/S1431927618004142 SN - 1431-9276 SN - 1435-8115 VL - 24 IS - S1 (August) SP - 730 EP - 731 PB - Cambridge University Press CY - New York, NY, U.S.A. AN - OPUS4-46006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Yamamoto, K. A1 - Grulke, E. A. T1 - Size and shape distribution of bipyramidal TiO2 nanoparticles by transmission electron microscopy – an inter-laboratory comparison N2 - Extraction of true, 3D shape (and size) of non-spherical nanoparticles (NPs) is associated with errors by conventional 2D electron microscopy using projection images. Significant efforts within the ISO technical committee TC 229 ‘Nanotechnologies’ are aimed at establishing accurate TEM and SEM measurement of NP size and shape as robust, standard procedures. Study groups have been organizing inter-laboratory comparisons on well-selected NP systems according to the market needs, such as aggregated titania nano-powder for which size and shape distribution of primary crystallites of irregular shape must be measured accurately. To be noticed is e. g. the fact that the measurement procedure allows only manual selection of the particles clearly distinguishable for analysis as well as manual definition of the contour of the imaged NPs. An inter-laboratory exercise on titania NPs (pure anatase, grown by hydrothermal synthesis) of well-defined non-spherical shape, i.e. bipyramidal has been recently started within ISO/TC 229 under similar conditions as for the irregular shaped titania. Overlapped particles were allowed to be considered, as long as they are clearly distinguishable. One decisive NP selection criterion was to analyze only those NPs with a roundness value below 0.7, i.e. the NPs laying on the support foil and, hence, with projection areas clearly deviating from perfect circles (R=1). The overall evaluation (for 15 labs) of the size descriptors (area, Feret, minFeret, perimeter) and shape descriptors (aspect ratio, roundness, compactness, extent) by analysis of variance is just to be finished and included in ISO/WD 21363 Nanotechnologies -- Protocol for particle size distribution by transmission electron microscopy. KW - Nanoparticles KW - Electron microscopy KW - Titanium oxide KW - Particle size distribution PY - 2018 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/size-and-shape-distribution-of-bipyramidal-tich-nanoparticles-by-transmission-electron-microscopy-an-interlaboratory-comparison/9E2FA0C716DB5F881E3032D014DFD52B DO - https://doi.org/10.1017/S1431927618009017 SN - 1431-9276 SN - 1435-8115 VL - 24 IS - S1 (August 2018) SP - 1706 EP - 1707 PB - Cambridge University Press CY - New York, NY, U.S.A. AN - OPUS4-46005 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Crasselt, Claudia A1 - Schmidt, Wolfram A1 - Sturm, Heinz T1 - Influence of rheology modifying admixtures on hydration of cementitious suspensions N2 - The presence of polycarboxylate ether (PCE) based superplasticizers (SPs) has an enormous influence on the early hydration of cement. Therefore, the talk presents first experimental results about the influence of a delayed addition time of PCE SPs on the hydration of cement and tricalcium aluminate (C3A) pastes, investigated by isothermal heat flow calorimetry and in-situ XRD. T2 - 38th Cement and Concrete Science Conference CY - Coventry, UK DA - 10.09.2018 KW - Cement hydration KW - Polycarboxylate ether KW - C3A hydration PY - 2018 AN - OPUS4-45996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Crasselt, Claudia A1 - Schmidt, Wolfram A1 - Sturm, Heinz ED - M. Tyrer, ED - E. Ganjian, ED - West, A. T1 - Influence of rheology modifying admixtures on hydration of cementitious suspensions N2 - The presence of polycarboxylate ether (PCE) based superplasticizers (SPs) has an enormous influence on the early hydration of cement. The hydration is retarded and the timing of formation and the morphology of hydrates is affected. This short paper presents experimental results about the influence of delayed Addition time of PCE SPs on hydration of cement and tricalcium aluminate (C3A) pastes, investigated by isothermal heat flow calorimetry. For cement pastes the hydration is retarded with SP, whereby the high charge PCE has a stronger retarding effect than the low charge PCE. With delayed PCE addition the cement shows a less retarded setting than with simultaneous addition. The alteration caused by PCE is much more pronounced for C3A and gypsum mixes than for cement. If the SP is added simultaneous, the exothermic peak of C3A is retarded. However, with delayed addition of SP the hydration is shortened, the gypsum depletion is fastened and the exothermic peak occurs less retarded or even accelerated compared to simultaneous addition. It is obvious that for C3A pastes there is less retardation the later the Addition of SP. Furthermore, the PCE alter the hydration of C3A when added delayed and exhibit changes in kinetics and hydration rates. The rate of reaction in the second stage is lower, discernible in decreased slopes and broader peaks. Besides this, a distinct ramp in the C3A heat flow curves within the first stage of C3A hydration occurs for all pastes with delayed addition of SP, which suggests an accelerated ettringite formation. T2 - 38th Cement and Concrete Science Conference CY - Coventry, UK DA - 10.09.2018 KW - Cement hydration KW - Polycarboxylate ether KW - C3A hydration PY - 2018 SN - 978-1-84600-088-1 SP - 64 EP - 67 CY - Coventry, UK AN - OPUS4-45995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Leinitz, Sarah A1 - Schmidt, Wolfram A1 - Mota, Berta A1 - Crasselt, Claudia T1 - Einfluss der wässrigen Phase von Zementleim und Polycarboxylatethern auf die Rheologie und die frühe Hydratation von Zement N2 - Die Rheologie von fließfähigen zementären Systemen mit Fließmitteln wird durch eine Vielzahl parallel stattfindender Effekte beeinflusst. Zu diesen Effekten zählen Wechselwirkungen zwischen den Polymeren und Ionen in der Porenlösung, frühe Phasenbildung, zeitabhängige und kompetitive Adsorption zwischen anionischen Polymeren und Sulfationen, Bildung von Phasen in der Porenlösung sowie Morphologieänderungen an Partikeloberflächen. Die frühe Hydratation von Zement, die durch Lösungs- und Fällungsprozesse angetrieben wird, beeinflusst diese Effekte erheblich. Das permanente Ungleichgewicht der Porenlösung führt zu Veränderungen der Partikeloberflächen, welches widerum zur Folge hat, dass rheometrische Messungen dieser Zementleime anfällig für Streuungen sind. Um die Einflüsse aus der Zementhydratation zu minimieren, wurden die rheometrischen Untersuchungen mit Zement in Wasser, wässriger Phase von Zementleim bzw. mit vorhydratisiertem Zement durchgeführt. Zusätzlich wurden die gleichen Systeme mit Zugabe von Polycarboxylatethern untersucht. Die Ergebnisse zeigen, dass die Leime mit Wasser niedrigere Werte für Fließgrenze und plastische Viskosität aufweisen, als die Systeme mit der wässrigen Phase von Zementleim. Während die Polymere eine Verminderung der Fließgrenze zur Folge hatte, war die Wirkung von Polymeren auf die plastische Viskosität vernachlässigbar. Zusätzlich wurde die frühe Hydratation unter Verwendung von Wärmeflusskalorimetrie, Rasterelektronenmikroskopie und Nadeleindringtiefe beobachtet. T2 - 20. Internationale Baustofftagung CY - Weimar, Germany DA - 12.09.2018 KW - Rheologie KW - Polycarboxylatether KW - Zementleim KW - Fließmittel PY - 2018 AN - OPUS4-45974 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Leinitz, Sarah A1 - Schmidt, Wolfram A1 - Mota, Berta A1 - Crasselt, Claudia ED - Ludwig, H.-M. T1 - Einfluss der wässrigen Phase von Zementleim und Polycarboxylatethern auf die Rheologie und die frühe Hydratation von Zement N2 - Die Rheologie von fließfähigen zementären Systemen mit Fließmitteln wird durch eine Vielzahl parallel stattfindender Effekte beeinflusst. Zu diesen Effekten zählen Wechselwirkungen zwischen den Polymeren und Ionen in der Porenlösung, frühe Phasenbildung, zeitabhängige und kompetitive Adsorption zwischen anionischen Polymeren und Sulfationen, Bildung von Phasen in der Porenlösung sowie Morphologieänderungen an Partikeloberflächen. Die frühe Hydratation von Zement, die durch Lösungs- und Fällungsprozesse angetrieben wird, beeinflusst diese Effekte erheblich. Das permanente Ungleichgewicht der Porenlösung führt zu Veränderungen der Partikeloberflächen, welches widerum zur Folge hat, dass rheometrische Messungen dieser Zementleime anfällig für Streuungen sind. Um die Einflüsse aus der Zementhydratation zu minimieren, wurden die rheometrischen Untersuchungen mit Zement in Porenlösung durchgeführt. Die Experimente wurden mit verschiedenen Feststoffvolumenfraktionen durchgeführt und mit den Ergebnissen identischer Systeme mit Wasser anstelle von Porenlösung verglichen. Zusätzlich wurden die gleichen Systeme mit Zugabe von Polycarboxylatethern untersucht. Die Ergebnisse zeigen, dass die Leime mit Wasser niedrigere Werte für Fließgrenze und plastische Viskosität aufweisen, als die Systeme mit Porenlösung. Während die Polymere eine Verminderung der Fließgrenze zur Folge hatte, war die Wirkung von Polymeren auf die plastische Viskosität vernachlässigbar. Zusätzlich wurde die frühe Hydratation unter Verwendung von Wärmeflusskalorimetrie, Rasterelektronenmikroskopie und Nadeleindringtiefe beobachtet. T2 - 20. Internationale Baustofftagung CY - Weimar, Germany DA - 12.09.2018 KW - Rheologie KW - Polycarboxylatether KW - Zementleim KW - Fließmittel PY - 2018 SN - 978-3-00-059950-7 VL - 20 SP - 744 EP - 751 PB - F.A. Finger-Institut für Baustoffkunde CY - Weimar AN - OPUS4-45973 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Kim, K. J. T1 - Measurement of Elemental Composition of FeNi and SiGe Thin Films by Electron Probe Microanalysis with Stratagem Software N2 - The present study repeats electron probe microanalysis (EPMA) measurements with the thin film analysis software Stratagem on an Fe-Ni thin films on silicon and reports - for the first-time – results of analysis on Si-Ge thin films deposited on a non-conductive aluminium oxide substrate. If the very good EPMA/Stratagem results for the FeNi system were expected due to previous studies [2], the data obtained for the SiGe films are particularly valuable, because of the challenging insulator substrate of Al2O3. The conductivity of the Si1-xGex surface necessary for charging-free analysis was ensured by applying conductive copper tape onto film surface down to sample stage. Four accelerating voltages, 15, 20, 25 and 30 kV, have been applied, so that the Ge Kα X-ray line at 9.87 keV could be excited. KW - thin film analysis KW - X-ray spectroscopy KW - Fe-Ni KW - Si-Ge KW - Stratagem KW - Electron probe microanalysis (EPMA) PY - 2018 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/measurement-of-elemental-composition-of-feni-and-sige-thin-films-by-electron-probe-microanalysis-with-stratagem-software/D4CF5D45B11FCF0DEC8155A89EDACF25 DO - https://doi.org/10.1017/S1431927618004282 VL - 24 IS - S1 (August) SP - 758 EP - 759 PB - Cambridge University Press CY - New York, NY, U.S.A. AN - OPUS4-45950 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sachse, René A1 - Hertwig, Andreas A1 - Kraehnert, R. A1 - Hodoroaba, Vasile-Dan T1 - Analysis of mesoporous iridium oxide thin films by the combined methodical approach SEM/EDS/STRATAGem N2 - For the determination of porosity of Ir oxide thin films, electron probe microanalysis (EPMA) can be used as part of a combined SEM/EDS/STRATAGem analysis. The mass deposition (in μg cm-2) of films was calculated with the analysis software STRATAGem via k-values measured with EDS. The average density of coated films was obtained from the mass deposition and the film thickness as measured by the cross-section SEM. The porosity was calculated by dividing the average film density by the bulk (theoretical) density of the film material. Film porosities were counterchecked by spectroscopic ellipsometry (SE) using the Bruggeman effective medium approximation (BEMA). The results obtained by both analytical approaches/methods used, SEM/EDS/STRATAGem and SE were in good agreement. KW - Porous thin films KW - Iridium oxide KW - Electron probe microanalysis (EPMA) KW - Spectroscopic ellipsometry PY - 2018 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/analysis-of-mesoporous-iridium-oxide-thin-films-by-the-combined-methodical-approach-semedsstratagem/7607018338B542D8B8C4D944392781EF DO - https://doi.org/10.1017/S1431927618004300 SN - 1431-9276 SN - 1435-8115 VL - 24 IS - S1 (August) SP - 762 EP - 763 PB - Cambridge University Press CY - New York, NY, U.S.A. AN - OPUS4-45951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Donėlienė, J. A1 - Rudzikas, M. A1 - Rades, Steffi A1 - Dörfel, Ilona A1 - Peplinski, Burkhard A1 - Sahre, Mario A1 - Pellegrino, F. A1 - Maurino, V. A1 - Ulbikas, J. A1 - Galdikas, A. A1 - Hodoroaba, Vasile-Dan T1 - Electron Microscopy and X-Ray Diffraction Analysis of Titanium Oxide Nanoparticles Synthesized by Pulsed Laser Ablation in Liquid N2 - A femto-second pulsed laser ablation in liquid (PLAL) procedure for the generation of titanium oxide nanoparticles (NP) is reported with the purpose of understanding morphology and structure of the newly generated NPs. Ablation duration was varied for optimization of NP generation processes between 10 and 90 min. Surface morphology of NPs as well as their size and shape (distribution) were analysed by various complementary electron microscopy techniques, i.e. SEM, TSEM and TEM. The crystalline structure of titanium oxide particles was investigated by XRD(two instruments operated in different geometries) and HR-TEM. Concentration of generated titanium oxide NPs in liquid was analysed by ICP-MS. A mix of crystalline (mainly anatase), partly crystalline and amorphous spherical titanium oxide NPs can be reported having a mean size between 10 and 20 nm, which is rather independent of the laser ablation (LA) duration. A second component consisting of irregularly shaped, but crystalline titanium oxide nanostructures is co-generated in the LA water, with more pronounced occurrence at longer LA times. The provenance of this component is assigned to those spherical particles generated in suspension and passing through the converging laser beam, being hence subject to secondary irradiation effects, e. g. fragmentation. KW - Laser ablation in liquid KW - Nanoparticles KW - Titanium oxide KW - Particle morphology PY - 2018 UR - https://www.cambridge.org/core/journals/microscopy-and-microanalysis/article/electron-microscopy-and-xray-diffraction-analysis-of-titanium-oxide-nanoparticles-synthesized-by-pulsed-laser-ablation-in-liquid/AE368446FAC70E08C514F9AEABFD131B DO - https://doi.org/10.1017/S1431927618009030 VL - 24 IS - S1 (August) SP - 1710 EP - 1711 PB - Cambridge University Press CY - New York, NY, U.S.A. AN - OPUS4-45949 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lee, Jun-Seob A1 - Radnik, Jörg A1 - Bäßler, Ralph T1 - Passivity of alloy 31 in green-death solution N2 - The passivation behavior of alloy 31 was investigated as a function of passivation potential in a green-death solution at 40 °C. The alloy 31 surface is in a stable passive state during cyclic potentiodynamic polarization. In potentiostatic polarization of alloy 31, passive current density increases with an increase in the passivation potential. Electrochemical impedance spectroscopy (EIS) and Mott–Schottky (M–S) analysis showed that a more defective n-type semiconductive passive film forms as the potential increases. X-ray photoelectron spectroscopy (XPS) revealed that passive film consists of mainly chromium and minor iron and nickel oxides. The increase of the applied potential is considered to be a reason for the change in passive film stability. KW - Passive film KW - Steel KW - Alloy 31 KW - X-ray photoelectron spectroscopy PY - 2018 DO - https://doi.org/10.1002/maco.201709996 SN - 0947-5117 SN - 1521-4176 VL - 69 IS - 9 SP - 1218 EP - 1226 PB - Wiley-VCH CY - Weinheim AN - OPUS4-45938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kleinbub, Sherin A1 - An, Biwen Annie A1 - Özcan Sandikcioglu, Özlem A1 - Dommisch, H. A1 - Koerdt, Andrea T1 - The impact of methanogenic Archaea on material, environment and health N2 - Microbiologically influence corrosion (MIC) has become a big concern due the increased usage of different metals by our society. Microorganisms can use metal as an electron donor, causing unpredictable but serious damages. Nowadays it is known that besides sulfate reducing bacteria (SRB), other microorganisms including acetogens, iron oxidizers and methanogens can also induce MIC. Current studies related to methanogen-induced MIC (MI-MIC) mainly focused on environmental isolates from the oil and gas industry (e.g. Methanococcus maripaludis) with industrial materials e.g. iron. However, MI-MIC can occur in many other environments as well, including the oral cavity. Methanobrevibacter oralis is a methanogen isolated from the human oral cavity and was found more frequently in patients suffering from peri-implantitis/periodontitis. Titanium-implants removed from those patients have also showed clear signs of corrosion. The aim of our study is to establish and analyze corrosion potentials of dental metals (e.g. titanium) by oral methanogens. Periodontal pockets samples from patients suffering from periodontitis/peri-implantitis were taken for methanogenic and SRB enrichments. Stainless steel, pure titanium or Ti-6Al-4V alloy was used for corrosion studies. Corrosion rates and methane production were measured using weight-loss method and gas chromatography, respectively. Metal surfaces were visualized with scanning electron microscopy. Microbial communities in the dental pockets of healthy people and patients will be compared using 16S rRNA amplicon sequencing. Overall, this is the first study investigating the susceptibility of different dental implant materials to corrosion using human-related Archaea. The outcomes of this study can be further explored for a variety of clinical applications. T2 - ISME 17th International Symposium on Microbial Ecology CY - Leipzig, Germany DA - 12.08.2018 KW - Methanogens KW - Corrosion KW - Biofilm PY - 2018 AN - OPUS4-45932 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yildirim, Arda A1 - Sentker, Kathrin A1 - Huber, Patrick A1 - Schönhals, Andreas T1 - Collective Orientational Order and Phase Behavior of a Discotic Liquid Crystal under Confinement N2 - Discotic liquid crystals (DLCs) are a promising class of soft matter for electronic applications. This is due to their ability to self-organize into columns in a hexagonal columnar mesophase, driven by the overlapping of the π orbitals of their aromatic cores. This leads to a high charge-carrier mobility along the column axis. Embedding liquid crystals into nanopores of anodic aluminum oxide (AAO) results in a 2D nanoconfinement of these materials. This confinement affects their properties, compared to the bulk, such as phase transition temperatures and enthalpies, molecular mobility, and crystallization. In this study, 2,3,6,7,10,11 hexakis[hexyloxy] triphenylene (HAT6) was confined into parallel aligned cylindrical nanopores of AAO membranes by melt infiltration. The membrane as confining hosts used have varying pore diameters, from 10 nm to 160 nm, covering a broad pore size range, thus, a better understanding of the confinement effect on phase behavior and molecular configuration in the pores. Furthermore, it is aimed to obtain axial ordering or to increase degree of axial ordering by chemically modifying the surfaces of the pores. Therefore, the pore surfaces the membranes were chemically modified, resulting in a more hydrophobic pore surface than the unmodified ones. The phase behavior was explored by a power-compensated DSC allowing the detecting of small changes in the phase behavior. In the literature, dielectric spectroscopy was demonstrated as a method to monitor molecular order inside the pores. Here, we also investigate the collective orientational order, corresponding to dominating molecular ordering, by dielectric spectroscopy. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussles, Belgium DA - 26.08.2018 KW - Confined Columnar Liquid Crystals PY - 2018 AN - OPUS4-45916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina A1 - Madkour, Sherif A1 - Schönhals, Andreas T1 - Molecular dynamics of an asymmetric PVME/PS Blend investigated by broadband dielectric and specific heat spectroscopy N2 - Over the past decades research on the molecular dynamics of miscible polymer blends are of topical interest in the literature, in an attempt to understand the segmental mobilty of individual components, as it is affected by blending. In general, miscible polymer blends exhibit a complex behavior of the molecular mobility. For an A/B blend the relaxation times of component A and component B are affected by the spatial local compositional heterogeneity, present in binary systems on a microscopic level, regardless of the macroscopic homogeneity. Here, a combination of broadband dielectric and specific heat spectroscopy was employed to study the dynamically asymmetric PVME/PS blend with seven different compositions, focusing on samples with high PS contents. Considering that PS is dielectrically invisible, BDS is a powerful technique to study the response of PVME, as it is affected by PS segments. In this work the well-known binary relaxation times distribution of PVME in a blend, originating from the spatial local heterogeneity, was studied over ten decades in frequency, for the first time in literature. Secondly, one of the detected processes, α’-relaxation, shows a crossover from high-temperature behavior (system in equilibrium) towards a low temperature regime, where PS undergoes the thermal glass transition, resulting in confined segmental dynamics of PVME within a frozen network of PS. Here, we introduce a precise mathematical tool to distinguish between the temperature dependency regimes of the process, and examine the composition dependence of the crossover temperature, detected by dielectric spectroscopy. Moreover, the dielectric data was compared in detail with results obtained by specific heat spectroscopy. This comparison provides new insights in the dynamics and dynamic heterogeneity of the PVME/PS blend system. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussels, Belgium DA - 26.08.2018 KW - Polymer blends KW - Dielectric spectroscopy KW - Specific heat spectroscopy PY - 2018 AN - OPUS4-45917 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina A1 - Schönhals, Andreas T1 - Rigid Amorphous Phase in Polymer Nanocomposites as Revealed by Relaxation Spectroscopy N2 - In inorganic/polymer nanocomposites the polymer matrix region near a filler surface, termed as the interphase, is of topical interest due to its possible influence on the macroscopic properties of the material. The segmental dynamics of this interphase is expected to be altered, as compared to the pure matrix, which might percolate into the entire system. It was found that a so-called Rigid Amorphous Phase (RAF) is formed in the interfacial region by adsorption of the polymer segments onto the nanoparticles, yielding in their immobilization. Here, we employed a combination of two relaxation spectroscopy techniques (Broadband Dielectric Spectroscopy (BDS) and Specific Heat Spectroscopy (SHS) in a form of Temperature Modulated DSC (TMDSC)) to investigate the structure and molecular mobility of Epoxy/Inorganic nanofiller composites with different nanoparticles geometries and contents. The two techniques show different perspectives on the glassy dynamics; BDS is sensitive to dipole fluctuations, whereas SHS senses entropy fluctuations. First, our dielectric relaxation investigations proved an existence of an additional process in nanocomposites, which is not present in the pure material. Due to the increasing intensity of the process with increasing filler content it was assigned as the α-process related to the segmental dynamics of polymer chains adsorbed onto the nanoparticles. Considering the expected high conductivity effects of the material, the dielectric data were analyzed by fitting a derivative of the HN function to a “conduction-free” loss spectra: ε''deriv=-(∂ε'/∂logω). Second, TMDSC measurements were used to study the specific heat capacity of nanocomposites in its nanofiller content dependence. Assuming that RAF is proportional to the decrease of the specific heat capacity step (Δcp) in the glass transition region of the nanocomposites, comparing to the pure material, the inorganic/polymer interphase was quantitatively analyzed and the amount of RAF estimated. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussels, Belgium DA - 26.08.2018 KW - Boehmite KW - Nanocomposites KW - Rigid amorphous fraction KW - BDS KW - TMDSC PY - 2018 AN - OPUS4-45915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yildirim, Arda A1 - Sentker, Kathrin A1 - Bühlmeyer, Andrea A1 - Laschat, Sabine A1 - Huber, Patrick A1 - Schönhals, Andreas T1 - Molecular dynamics of dipole functionalized triphenylene-based discotics N2 - Since discovery of discotic liquid crystals (DLCs), consisting of a disklike rigid aromatic core and flexible alkyl chains attached to the core, dating back to Chandrasekhar’s work in 1977, they have been extensively investigated to reveal their fundamental properties and potential for applications. The researches on DLCs in last decades showed that DLCs can be considered as promising materials for organic electronic applications since they exhibit one dimensional high charge mobility along the column axis in a columnar mesophase. The mobilies of the rigid aromatic core and the flexible alkyl chains can influence their application properites, e.g. the charge carrier mobility, therefore, it needs to be explored in detailed. In this study, a series of dipole functionalized triphenylene-based discotics, forming a columnar mesophase, were investigated to reveal the influence of the functionalization on phase behavior, molecular dynamics and as well as conductivity. The molecular mobility of the discotics was probed by broadband dielectric spectroscopy (BDS). In addition to conductivity and localized dynamics, glassy dynamics were also observed. The phase behavior of the material was explored by a power-compansated differential scanning calorimetry (DSC). Beside the phase transition temperatures and enthalpies, thermal glass transitions were found for all the materials. Moreover, the glassy dynamics were further investigated by Flash DSC, which is a chip-based calorimetry technique allows fast heating and cooling rates as high as 10000K/s. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussles, Belgium DA - 26.08.2018 KW - Columnar liquid crystals PY - 2018 AN - OPUS4-45918 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yildirim, Arda A1 - Szymoniak, Paulina A1 - Sentker, Kathrin A1 - Huber, Patrick A1 - Schönhals, Andreas T1 - Molecular Mobility and Ionic Conductivity of Ionic Liquid Crystals Forming a Hexagonal Columnar Mesophase N2 - For the first time, the molecular mobility of two linear-shaped tetramethylated guanidinium triflates ionic liquid crystals (ILCs) having different length of alkyl chains was investigated by a combination of broadband dielectric spectroscopy (BDS) and specific heat spectroscopy (SHS). By self-assembly, these ILCs can form a hexagonal ordered mesophase besides plastic crystalline phases and the isotropic state. SHS was carried out by differential AC-chip calorimetry at higher frequencies and temperature modulated DSC at lower frequencies. Two relaxation processes were found by BDS for both samples. At low temperatures, a γ-processes is observed which is assigned to specific localized fluctuations. At higher temperatures, α1-processes take place. α2 processes were also detected by SHS but with a completely different temperature dependence of the relaxation times. Different molecular assignments of α1- and α2-processes are suggested. At even higher temperatures, conductivity was detected by BDS. An increase in the DC conductivity by four orders of magnitude at the phase transition from the plastic crystalline to the hexagonal columnar mesophase is found. This result is traced to a change in the charge transport mechanism from a delocalized electron hopping in the stacked aromatic systems (in the plastic phase) to one dominated by an ionic conduction in the quasi-1D ion channels formed along the supermolecular columns in the ILC hexagonal mesophases. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussles, Belgium DA - 26.08.2018 KW - Ionic Liquid Crystals PY - 2018 AN - OPUS4-45914 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Szymoniak, Paulina A1 - Madkour, Sherif A1 - Schönhals, Andreas T1 - Dynamics of nanoscopically confined PVME in thin films of an asymmetric miscible PVME/PS blend N2 - In recent years, substantial efforts have been devoted to investigating nanoscopic confinement of polymers, and its effect on glassy dynamics. Broadband Dielectric Spectroscopy (BDS) was used to study the dynamics of ultra-thin films of PVME/PS 50/50 wt% blend, employing a novel nano-structured capacitor sample arrangement. The investigated system shows a complex dynamic behavior. First, an α-relaxation, related to a bulk-like layer was found. Second, an α’-relaxation was observed, characteristic for dynamically asymmetric blends, where the out of equilibrium dynamics is attributed to weakly-cooperative PVME segments relaxing within a frozen environment of PS segments. Third, for thinnest films, an Arrhenius-like process was dominant in the dielectric spectra, indicating localized fluctuations of the segments. Relaxation rates of this process resembled that of the degenerated α-relaxation of the adsorbed layer, found for pure PVME [1], thus it was assigned accordingly. For thinnest films, this process undergoes a further confinement, due to the topological constraints, introduced by PS. Such multiple confinement effect has not been reported for ultra-thin films of polymer blends, before this study [2]. [1] Madkour, S. et al. ACS Appl. Mater. Interfaces 2017, 9, 7535. [2] Madkour, S. et al. ACS Appl. Mater. Interfaces 2017, 9, 37289. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussels, Belgium DA - 26.08.2018 KW - Polymer blends KW - Thin polymer films KW - Dielectric spectroscopy KW - Specific heat spectroscopy PY - 2018 AN - OPUS4-45919 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Santos de Freitas, M. A1 - Araghi, R. R. A1 - Brandenburg, E. A1 - Leiterer, Jork A1 - Emmerling, Franziska A1 - Folmert, K. A1 - Gerling-Driessen, U. I. M. A1 - Bardiaux, B. A1 - Böttcher, C. A1 - Pagel, K. A1 - Diehl, A. A1 - v. Berlepsch, H. A1 - Oschkinat, H. A1 - Koksch, B. T1 - The protofilament architecture of a de novo designed coiled coil-based amyloidogenic peptide N2 - Amyloid fibrils are polymers formed by proteins under specific conditions and in many cases they are related to pathogenesis, such as Parkinson’s and Alzheimer’s diseases. Their hallmark is the presence of a β-sheet structure. High resolution structural data on these systems as well as information gathered from multiple complementary analytical techniques is needed, from both a fundamental and a pharmaceutical perspective. Here, a previously reported de novo designed, pH-switchable coiled coil-based peptide that undergoes structural transitions resulting in fibril formation under physiological conditions has been exhaustively characterized by transmission electron microscopy (TEM), cryo-TEM, atomic force microscopy (AFM), wide-angle X-ray scattering (WAXS) and solid-state NMR (ssNMR). Overall, a unique 2-dimensional carpet-like assembly composed of large coexisiting ribbon-like, tubular and funnel-like structures with a clearly resolved protofilament substructure is observed. Whereas electron microscopy and scattering data point somewhat more to a hairpin model of β-fibrils, ssNMR data obtained from samples with selectively labelled peptides are in agreement with both, hairpin structures and linear arrangements. KW - Amyloid KW - Elektronenmikroskopie PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-458713 UR - https://www.sciencedirect.com/science/article/pii/S1047847718301333 DO - https://doi.org/10.1016/j.jsb.2018.05.009 SN - 1047-8477 VL - 203 IS - 3 SP - 263 EP - 272 PB - Elsevier AN - OPUS4-45871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Saatz, Jessica A1 - Grunert, Bianca A1 - Jakubowski, Norbert A1 - Hoffmann, Katrin A1 - Resch-Genger, Ute A1 - Emmerling, Franziska T1 - Tagging reagents for imaging mass cytometry N2 - In der klinischen Diagnostik werden für zytometrische Messverfahren bereits eine Reihe von Reagenzien eingesetzt zur Markierung von Antikörper eingesetzt, um die Detektion von Biomarkern mittels Fluoreszenz- oder Flugzeitmassenspektrometrie zu ermöglichen. Seit kurzem ist auch eine Imaging Mass Cytometry Kombination direkt erhältlich, wodurch der Nachweis von Biomarkern in Gewebeschnitten erreicht werden kann. Dazu wird eine Kopplung von Laser Ablation und induktiv gekoppeltem Plasma Massenspektrometrie eingesetzt, wobei ähnlich der Massenzytometrie, zuvor Antikörper mit Metallen markiert, und im Anschluss mit dem Gewebeschnitt inkubiert werden. Durch die hohe Ortsauflösung können die Biomarker lokalisiert, und zukünftig vielleicht auch quantifiziert werden. Insbesondere Lanthanide eignen sich als Markierungsmetalle, da sie einen niedrigen Untergrund und chemisch ähnliches Verhalten zueinander aufweisen. Allein durch diese Elemente können bereits etwa 15 Parameter unterschieden werden, was durch isotopenreine Standards weiter gesteigert werden kann. Vom Markierungsgrad abhängig werden unterschiedlich viele Metalle am Antikörper gebunden, und beeinflussen so die Sichtbarkeit im ICP-MS. Nanopartikel könnten daher eine deutliche Steigerung der Sensitivität bewirken. GdVO4 Nanokristalle scheinen bisher sehr vielversprechend und bieten neben multiparametrischen Anwendungen auch Multimodalität. Die Synthese der Nanokristalle zeigte hohe Homogenität und Reproduzierbarkeit in Partikelgröße in der Zusammensetzung. Ein erstes Experiment mit einer Zellkultur konnte bereits die effiziente Markierung der Zellen unter Beweis stellen, wobei durch hohe Signalstärke auch subzelluläre Auflösung in der LA-ICP-MS erreicht werden konnte. T2 - ICPMS Anwendertreffen 2018 CY - Berlin, Germany DA - 03.09.2018 KW - LA-ICP-MS KW - Immuno assay KW - Bioimaging KW - Nanocrystal KW - Lanthanide KW - Metal-tag PY - 2018 AN - OPUS4-45866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griepentrog, Michael T1 - Towards the standardization of dynamic instrumented indentation testing N2 - Nowadays the Instrumented Indentation Testing (IIT) is one of the most commonly used methods to determine the mechanical properties of materials in the nano range. This method is already extensive standardized in EN ISO 14577 part 1-4. Because of the great interest of researchers and industries in investigations of time depending material behavior mostly all suppliers of IIT equipment are offering the possibility of dynamic testing. Realizing this development ISO/TC 164/SC3 Hardness Testing has proposed to start the new standardization project “Linear elastic dynamic instrumented indentation testing DIIT”. The development of this standard is accompanied by the first international intercomparing exercise comparing results of dynamic instrumented indentation testing from testing machines using different hardware solutions and different models for data evaluation. The draft of part 5 of ISO 14577 “Linear elastic dynamic instrumented indentation testing DIIT” specifies verification and calibration of testing machines for carrying out the measurement of the dynamic material response when an oscillatory force or displacement, with amplitudes small in comparison to the prescribed target values, is imparted to the indenter while the indenter is continuously loaded to a prescribed target load or target depth or while the load or displacement is held constant at a prescribed target value. In case of a material showing plastic-elastic behavior, the measured dynamic response is used for continuous evaluation of the dynamic stiffness of the contact as a function of depth and frequency. Using the dynamic stiffness of the contact a reduced dynamic modulus will be calculated. In case of a material showing visco-elastic behavior from the measured dynamic response also the dynamic contact damping coefficient as function of depth and frequency is evaluated continuously. Using dynamic contact stiffness and dynamic contact damping coefficient reduced lost and storage modulus for visco-elastic materials will be calculated. The main normative requirements of the draft will be presented and discussed in the light of the first results of the intercomparing excise. T2 - IIW6, International Indentation Workshop 6 CY - Sapporo, Japan DA - 02.07.2018 KW - ISO 14577 KW - Instrumented indentation testing KW - Nanoindentation KW - IIT KW - Mechanical properties KW - Dynamic testing KW - Visco-elastic KW - Loss module KW - Storage module PY - 2018 AN - OPUS4-45850 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönhals, Andreas A1 - Madkour, Sherif A1 - Gawek, Marcel A1 - Szymoniak, Paulina A1 - Hertwig, Andreas T1 - Growth kinetics and molecular mobility of irreversibly adsorbed layers in thin polymer films N2 - In well-annealed thin polymer films, with non-repulsive polymer/substrate interactions, an irreversibly adsorbed layer is expected to from. These adsorbed layers have shown greate potential for technological applications. However, their growth kinetics and molecular dynamics are still not fully understood. This is partly due to the hard accessibility of these layers in thin films. Here, the irreversibly adsorbed layers of homopolymer thin films are revealed by solvent-leaching experiments. First, the growth kinetics of these layers is investigated as a function of annealing time, annealing temperature, leaching time and the original filme thickness. The film thickness, topography and the quality of the adsorbed layer is controlled by Atomic Force Microscopy (AFM). Secondly, the molecular mobility of the adsorbed layer is investigated by Broadband Dielectric Spectroscopy (BDS). A recently developed nanostructured capacitor arrangement is employed to measure the layer with a free surface. The results are quantitatively compared and discussed with respect to recently published work. T2 - 10th Conference on Broadband Dielectric Spectroscopy and its Applications CY - Brussles, Belgium DA - 26.08.2018 KW - Thin polymer films PY - 2018 AN - OPUS4-45837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baer, D. R. A1 - Karakoti, A. S. A1 - Clifford, C. A. A1 - Minelli, C. A1 - Unger, Wolfgang T1 - Importance of sample preparation on reliable surface characterisation of nano‐objects: ISO standard 20579‐4 N2 - The international ISO Standard 20579‐4, dealing with the history and preparation of nano‐objects for surface analysis, has been developed to help address some of the replication and reproducibility issues caused by the fundamental nature of nanoobjects. Although all types of samples requiring surface analysis need thoughtful preparation, nano‐objects, for which many properties are controlled by their surfaces, present additional challenges in order to avoid variations and artefacts due to the handling and preparation of materials prior to analysis. This international standard is part of a series of standards related to preparation of samples for surface chemical analysis. Parts 1 and 2 of ISO Standard series 20579 address general issues that apply to many samples. Part 3, which is still in development, will focus on biomaterials. Part 4 specifically considers issues that arise due to the inherent nature of nano‐objects. Because of sensitivity to their environment, the standard indicates the minimum Information that needs to be reported about the handling and preparation of nano‐objects prior to surface analysis. This information should become part of sample provenance information that helps assure the reliability and usefulness of data obtained from surface‐analysis in the context of the synthesis, processing, and analysis history of a batch of material. Application of this standard can help address reproducibility and traceability issues associated with synthesis, processing, and characterization of nano‐objects in research and commercial applications. KW - Nano‐object characterization KW - Nanoparticle characterization KW - Provenance information KW - Sample preparation KW - Surface analysis PY - 2018 DO - https://doi.org/10.1002/sia.6490 SN - 0142-2421 SN - 1096-9918 VL - 50 IS - 9 SP - 902 EP - 906 PB - John Wiley & Sons, Ltd. AN - OPUS4-45830 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul A1 - Unger, Wolfgang T1 - Summary of ISO/TC 201 technical report: ISO/TR 19693 surface chemical analysis—characterization of functional glass substrates for biosensing applications N2 - ISO/TR 19693:2018—Surface chemical analysis—Characterization of functional glass substrates for biosensing applications gives an overview of methods, strategies, and guidance to identify possible sources of problems related to substrates, device production steps (cleaning, activation, and chemical modification), and shelf life (storage conditions and aging). It is particularly relevant for surface chemical analysts characterizing glass‐based biosensors, and developers or quality managers in the biosensing device production community. Based on quantitative and qualitative surface chemical analysis, strategies for identifying the cause of poor Performance during device manufacturing can be developed and implemented. A review of measurement capabilities of surface analytical methods is given to assist readers from the biosensing community. KW - Bio sensing device KW - Surface chemical analysis KW - XPS KW - SIMS KW - Standardization PY - 2018 DO - https://doi.org/10.1002/sia.6481 SN - 0142-2421 SN - 1096-9918 VL - 50 IS - 8 SP - 835 EP - 838 PB - John Wiley & Sons, Ltd. AN - OPUS4-45829 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Terborg, R. A1 - Procop, Mathias T1 - Check of the performance of EDS systems attached to the SEM with the test material EDS-TM001/2 and evaluation software package EDS spectrometer test -application, experiences and updates N2 - The test material EDS-TM001 together with an accompanying software package, “EDX spectrometer check”, have been made available in 2009 by BAM to be employed by EDS (energy dispersive spectrometer) users to check the performance of an EDS attached to the SEM. Particularly for test laboratories operating under accreditation schemes like ISO/IEC 17025, a periodical control of the critical instrumental parameters in end-user laboratories is required. With EDS-TM001 or EDS-TM002 (second generation) test material, this periodical check is simplified to the acquisition of only one 10 kV spectrum. The software “EDX spectrometer check” is destined to evaluate automatically this spectrum and determine the performance of the EDS in terms of energy resolution and calibration as well as possible alteration of low-energy efficiency due to detector contamination. Energy resolution can be compared with the specified values according to the international ISO standard ISO 15632:2012. EDS-TM is a synthetic material consisting of a thick layer of C, Al, Mn, Cu and Zr in a well-defined composition, deposited on a steel (in case of EDS-TM001) or silicon (in case of EDS-TM002) substrate. Meanwhile, more than one hundred laboratories use the EDS-TM001 or EDS-TM002 test material for the periodical check of their EDS. A detailed description of the test material and software together with examples of application was published recently. New results and gained experiences will be presented as well. When the FWHM of lines appearing in the EDS-TM spectrum are determined, the spectrum background must be subtracted accurately. The applied physical background subtraction procedure is robust and takes into account the transmission of the detector window. While the previous version considers only Moxtek AP windows, the new version includes selection of silicon nitride window and the case of windowless detector. Moreover, the new version allows importing of spectra in Bruker spx format and EMSA/MSA files from EDAX TEAM software. T2 - Microscopy & Microanalysis 2018 CY - Baltimore, MD, USA DA - 05.08.2018 KW - X-ray spectrometer KW - EDS KW - SEM KW - Performance check KW - Test material PY - 2018 AN - OPUS4-45751 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hodoroaba, Vasile-Dan A1 - Yamamoto, K. A1 - Grulke, E. A. A1 - Maurino, V. T1 - Size and shape distribution of bipyramidal TiO2 nanoparticles by TEM - An inter-laboratory comparison N2 - Extraction of true, 3D shape (and size) of non-spherical nanoparticles (NPs) is associated with errors by conventional 2D electron microscopy using projection images. Significant efforts within the ISO technical committee TC 229 ‘Nanotechnologies’ are aimed at establishing accurate TEM and SEM measurement of NP size and shape as robust, standard procedures. Study groups have been organizing inter-laboratory comparisons on well-selected NP systems according to the market needs, such as aggregated titania nano-powder for which size and shape distribution of primary crystallites of irregular shape must be measured accurately. To be noticed is e. g. the fact that the measurement procedure allows only manual selection of the particles clearly distinguishable for analysis as well as manual definition of the contour of the imaged NPs. An inter-laboratory exercise on titania NPs (pure anatase, grown by hydrothermal synthesis) of well-defined non-spherical shape, i.e. bipyramidal has been recently started within ISO/TC 229 under similar conditions as for the irregular shaped titania. Overlapped particles were allowed to be considered, as long as they are clearly distinguishable. One decisive NP selection criterion was to analyze only those NPs with a roundness value below 0.7, i.e. the NPs laying on the support foil and, hence, with projection areas clearly deviating from perfect circles (R=1). The overall evaluation (for 15 labs) of the size descriptors (area, Feret, minFeret, perimeter) and shape descriptors (aspect ratio, roundness, compactness, extent) by analysis of variance is just to be finished and included in ISO/WD 21363 Nanotechnologies -- Protocol for particle size distribution by transmission electron microscopy. T2 - Microscopy & Microanalysis 2018 CY - Baltimore, MD, USA DA - 05.08.2018 KW - Nanoparticles KW - Electron microscopy KW - ISO KW - Nanotechnology PY - 2018 AN - OPUS4-45750 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Koerdt, Andrea A1 - An, Biwen Annie A1 - Özcan Sandikcioglu, Özlem A1 - Widdel, F. T1 - Microbial corrosion of iron coupled to methanogenesis by strains from different environments N2 - Microbially influenced corrosion (MIC) of iron is usually attributed to sulfate-reducing microorganisms (SRM) which act upon the metal by the reactiveness of hydrogen sulfide, and by withdrawal of the available electrons (Fe → Fe²⁺ + 2e⁻ ; E° = 0.47 V) in electrical contact through surface attachment. Also methanogenic archaea are supposed to cause MIC. Because they do not produce hydrogen sulfide, withdrawal of electrons may be their main corrosive mechanism; however, mechanistic details and kinetics of the overall process are poorly understood. Precipitation of siderite (4Fe + 5HCO₃⁻ + 5H⁺ → 4FeCO₃ + CH₄ + 3H₂O) can lead to an insulating layer on the metal surface and lower the corrosion rate. Still, the extent of FeCO₃ precipitation may be significantly influenced by environmental conditions such as pH and advective processes. To investigate the corrosive potential of methanogens, we studied strains isolated from marine sediments (Methanococcus maripaludis 14266, 2067, Methanobacterium-affiliated strain IM1), crude oil tanks (Methanococcus maripaludis Mic1c10, KA1) and the oral cavity (Methanobrevibacter oralis) in a closed (batch) culture, and in a sand-packed flow-through cell with pH control and simulation of a fluctuating environment. Results indicate that the rates of iron corrosion due to coupled methanogenesis (up to 0.3 mm/yr) are comparable to that caused by SRM. Surface analyses of the metal showed severe pitting. Such knowledge and deeper understanding also from an electrokinetic point of view may not only provide further models in microbial electrophysiology, but also contribute to mitigation strategies in MIC. T2 - ISME 17th International Symposium on Microbial Ecology CY - Leipzig, Germany DA - 12.08.2018 KW - Corrosion KW - Methanogens KW - Biofilm KW - Flow-System KW - Iron PY - 2018 AN - OPUS4-45735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schaepe, Kaija A1 - R. Bhandari, D. A1 - Werner, J. A1 - Henss, A. A1 - Pirkl, A. A1 - Kleine-Boymann, M. A1 - Rohnke, M. A1 - Wenisch, S. A1 - Neumann, E. A1 - Janek, J. A1 - Spengler, B. T1 - Imaging of lipids in native human bone sections using TOF-secondary ion mass spectrometry, atmospheric pressure scanning microprobe matrix-assisted laser desorption/ionization orbitrap mass spectrometry, and orbitrap-secondary ion mass spectrometry N2 - A method is described for high-resolution label-free molecular imaging of human bone tissue. To preserve the lipid content and the heterogeneous structure of osseous tissue, 4 μm thick human bone sections were prepared via cryoembedding and tape-assisted cryosectioning, circumventing the application of organic solvents and a decalcification step. A protocol for comparative mass spectrometry imaging (MSI) on the same section was established for initial analysis with time-of-flight secondary ion mass spectrometry (TOF-SIMS) at a lateral resolution of 10 μm to <500 nm, followed by atmospheric pressure scanning microprobe matrix-assisted laser desorption/ionization (AP-SMALDI) Orbitrap MSI at a lateral resolution of 10 μm. This procedure ultimately enabled MSI of lipids, providing the lateral localization of major lipid classes such as glycero-, glycerophospho-, and sphingolipids. Additionally, the applicability of the recently emerged Orbitrap-TOF-SIMS hybrid system was exemplarily examined and compared to the before-mentioned MSI methods. KW - ToF-SIMS KW - MALDI KW - Mass spectrometry imaging KW - Lipids KW - Osteoporosis KW - Bone KW - Surface analysis PY - 2018 UR - https://pubs.acs.org/doi/10.1021/acs.analchem.8b00892 DO - https://doi.org/10.1021/acs.analchem.8b00892 SN - 0003-2700 SN - 1520-6882 VL - 90 IS - 15 SP - 8856 EP - 8864 PB - ACS Publ. CY - Washington, DC AN - OPUS4-45730 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kjaervik, Marit A1 - Schwibbert, Karin A1 - Dietrich, P. A1 - Thissen, A. A1 - Unger, Wolfgang T1 - Near-ambient pressure XPS of hydrated Escherichia coli samples with EnviroESCA N2 - This application note presents how EnviroESCA can be used to analyze E. coli biofilms on silicon under near ambient pressure conditions in various states of hydration. Such investigations of the outer bacterial cell surface in their hydrated state are essential for studying biological interfaces at work. KW - Biofilms KW - E. coli KW - NAP-XPS PY - 2018 UR - http://www.enviroai.com/uploads/1/0/2/8/102861712/nap_xps_of_escherichia_coli_samples.pdf IS - Application Note #000400 SP - 1 EP - 4 CY - Berlin, Germany AN - OPUS4-45720 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kjaervik, Marit A1 - Dietrich, P. A1 - Thissen, A. A1 - Petrik, S. A1 - Unger, Wolfgang T1 - Surface characterisation of bacteria and biofilms by NAP-XPS N2 - INTRODUCTION: X-ray photoelectron spectroscopy (XPS) provides elemental and chemical information from the outermost ~10 nm of the sample surface. This is in the same order of magnitude as the thickness of the outer bacterial membrane of gram-negative bacteria, as well as outer membrane molecules as exopolysaccharides and lipopolysaccharides, commonly attached to the cell surface. With the development of near-ambient pressure (NAP)-XPS, bacteria can be analysed with minimal sample preparation. This is in contrast to ultra-high vacuum XPS, where complex sample preparation including freeze-drying or fast-freezing is required, a treatment that may introduce artefacts or degrade the biological constituents. METHODS: EnviroESCA is a laboratory based NAP-XPS instrument, equipped with a monochromated Al Kα radiation source and a differentially pumped energy analyser connected to an exchangeable sample environment, a basic build-up is displayed in Figure 1c. It allows for measurements in various gas-atmospheres, including water vapor, which makes it possible to characterise bacteria and other biological samples close to their natural, hydrated state. Artificial model-biofilms of exopolysaccharides, planktonic Pseudomonas Fluorescens and biofilms of Escherichia Coli have been characterised in hydrated and dried state. RESULTS: High-resolution XPS-spectra from carbon, oxygen, nitrogen and phosphorous can be assigned to carbohydrates, lipids and proteins in general agreement with litterature2,3. Especially the carbon 1s peak is of interest (see Figure 1a and b), which reveal components originating from aliphatic carbon, single bounded carbon and double bounded/acetal carbon. A series of measurements of an E. coli biofilm from 11 mbar in humid environment to 1 mbar air reveal changes in the C1s peak, which suggests that the bacterial surface undergo substantial change. DISCUSSION & CONCLUSIONS: Bacterial samples can be analysed under near-ambient pressure conditions in various states of hydration with minimal sample preparation. Such investigations of bacterial cell wall surfaces are essential for studying biological interfaces at work. T2 - Biointerfaces International Conference CY - Zurich, Switzerland DA - 14.08.2018 KW - Bacteria KW - E. coli KW - NAP-XPS KW - Biofilms KW - Alginate PY - 2018 AN - OPUS4-45717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Theiler, Geraldine A1 - Wachtendorf, Volker A1 - Elert, Anna Maria A1 - Weidner, Steffen T1 - Effects of UV radiation on the friction behavior of thermoplastic polyurethanes N2 - The effects of weathering exposure on unfilled and filled thermoplastic polyurethanes (TPU) materials are described as performed under different humidity conditions. For this purpose, a weathering device was used with UV-A 340 nm lamps at a constant temperature of 40 °C. The effects of environmental (UV and humidity condition) degradation on the frictional properties of TPU materials are presented along with surface analyses to characterize the chemistry of the degradative process. Photooxidative degradation of unfilled polymer leads to deterioration of physical and mechanical properties, which affects its tribological behavior significantly. Due to crosslinking, the stiffness of the material increases, reducing drastically the friction coefficient of unfilled TPUs. The frictional behavior of glass fiber reinforced TPU is less affected by radiation. KW - Photooxidation KW - UV radiation KW - Friction KW - TPU KW - Humidity PY - 2018 DO - https://doi.org/10.1016/j.polymertesting.2018.08.006 SN - 0142-9418 SN - 1873-2348 VL - 70 SP - 467 EP - 473 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-45709 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brzeska, J. A1 - Elert, Anna Maria A1 - Morawska, M. A1 - Sikorska, W. A1 - Kowalczuk, M. A1 - Rutkowska, M. T1 - Branched Polyurethanes Based on Synthetic Polyhydroxybutyrate with Tunable Structure and Properties N2 - Branched, aliphatic polyurethanes (PURs) were synthesized and compared to linear analogues. The influence of polycaprolactonetriol and synthetic poly([R,S]-3-hydroxybutyrate) (R,S-PHB) in soft segments on structure, thermal and sorptive properties of PURs was determined. Using FTIR and Raman spectroscopies it was found that increasing the R,S-PHB amount in the structure of branched PURs reduced a tendency of urethane groups to hydrogen bonding. Melting enthalpies (on DSC thermograms) of both soft and hard segments of linear PURs were higher than branched PURs, suggesting that linear PURs were more crystalline. Oil sorption by samples of linear and branched PURs, containing only polycaprolactone chains in soft segments, was higher than in the case of samples with R,S-PHB in their structure. Branched PUR without R,S-PHB absorbed the highest amount of oil. Introducing R,S-PHB into the PUR structure increased water sorption. Thus, by operating the number of branching and the amount of poly([R,S]-3-hydroxybutyrate) in soft segments thermal and sorptive properties of aliphatic PURs could be controlled. KW - IR KW - Polyurethane KW - PUR KW - RAMAN PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-457087 DO - https://doi.org/10.3390/polym10080826 VL - 10 IS - 8 SP - 826, 1 EP - 12 PB - MDPI AN - OPUS4-45708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emmerling, Franziska A1 - Haferkamp, Sebastian A1 - Kraus, Werner T1 - Studies on the mechanochemical Knoevenagel condensation of fluorinated benzaldehyde derivates N2 - The mechanochemical Knoevenagel condensation of three fluorinated benzaldehyde derivates and malononitrile was investigated. The reactions were performed under solvent- and catalyst-free conditions and resulted in highly crystalline products after crystallization from a viscous phase in the milling jar. The quality of the obtained crystals was sufficient for single-crystal X-ray diffraction circumventing a recrystallization step. To gain more information on the reaction, progress was investigated in situ using time-resolved Raman spectroscopy. The results show a direct conversion of the reactants. KW - C-C coupling KW - Knoevenagel condensation KW - In situ KW - Mechanochemistry PY - 2018 DO - https://doi.org/10.1007/s10853-018-2492-0 SN - 0022-2461 VL - 53 IS - 19 SP - 13713 EP - 13718 PB - Springer Link AN - OPUS4-45682 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Becker, Roland A1 - Altmann, Korinna A1 - Braun, Ulrike T1 - Querschnittsthema Referenzmaterialien: Planung Ringversuche N2 - Nach einer Erläuterung der international üblichen Definitionen von Referenzmaterialien und Matrix-Referenzmaterialien erfolgt eine Zusammenfassung der spezifischen Anforderungen bei Herstellung und Charakterisierung. Weiterhin werden die unterschiedlichen Anforderungen an die Durchführung von Ringversuchen im Sinne eines Methodenvergleiches, einer Eignungsprüfung von Laboratorien und der Zertifizierung von Matrix-Referenzmaterialien gegenübergestellt. Für den aktuell geplanten ersten Ringversuch zur Quantifizierung von Mikroplastik in Schwebstoffen mittels thermischer Verfahren werden die konkreten technischen Bedingungen zur Herstellung entsprechender Referenzmaterialien einschließlich der Homogenitätsprüfung ihrer Mikroplastikgehalte dargestellt. Die Besonderheiten des Ringversuches vor dem Hintergrund einer Normung der eingesetzten Verfahren werden diskutiert. T2 - Forschungsschwerpunkt „Plastik in der Umwelt – Quellen • Senken • Lösungsansätze“: 2. Workshop des Querschnittsthemas „Analytik und Referenzmaterialien“ CY - Augsburg, Germany DA - 4.7.2018 KW - Mikroplastik KW - Referenzmaterialien KW - Ringversuche KW - Thermische Verfahren KW - Schwebstoffe KW - Methodenvergleich PY - 2018 AN - OPUS4-45681 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Breitfeld, Steffen A1 - Scholz, G. A1 - Emmerling, Franziska A1 - Kemnitz, E. T1 - BaF-benzenedicarboxylate: the first mechanochemical N2 - Anewbariumcoordination polymer, BaF-benzenedicarboxylate (BaF(p-BDC)0.5), with fluorine directly coordinated to the metal cation, was prepared by mechanochemical synthesis routes. Phase-pure BaF-benzenedicarboxylate was synthesized by milling starting either from barium hydroxide or from Barium acetate as sources for barium cations. In both cases, the second reactant was 1,4-benzenedicarboxylic acid (H2(p-BDC)). Ammonium fluoride was used as fluorinating agent directly at milling. This is the first mechanochemical synthesis of coordination polymers where fluorine is directly coordinated to the metal cation. Following the second possibility, barium acetate fluoride (Ba(OAc)F) is formed as ntermediate product after milling, and the new coordination polymer is accessible only after washing with water and dimethyl sulfoxide. The new compound BaF(p-BDC)0.5 was characterized by X-ray powder diffraction, FTIR-, and 19F, 1H-13C CP MAS NMR spectroscopies, DTA-TG, and elemental Analysis. KW - Milling KW - MOF PY - 2018 DO - https://doi.org/10.1007/s10853-018-2331-3 SN - 0022-2461 VL - 53 IS - 19 SP - 13682 EP - 13689 PB - Springer AN - OPUS4-45677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Akhmetova, Irina A1 - Schuzjajew, K. A1 - Wilke, M. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Rademann, K. A1 - Roth, C. A1 - Emmerling, Franziska T1 - Synthesis, characterization and in situ monitoring of the mechanochemical reaction process of two manganese(II)-phosphonates with N-containing ligands N2 - Two divalent manganese aminophosphonates, manganese mono (nitrilotrimethylphosphonate) (MnNP3) and manganese bis N-(carboxymethyl)iminodi(methylphosphonate)) (Mn(NP2AH)2), have been prepared by mechanochemical synthesis and characterized by powder X-ray diffraction (PXRD). The structure of the novel compound Mn(NP2AH)2 was determined from PXRD data. MnNP3 as well as Mn(NP2AH)2 exhibits a chain-like structure. In both cases, the manganese atom is coordinated by six oxygen atoms in a distorted octahedron. The local coordination around Mn was further characterized by extended X-ray absorption fine structure. The synthesis process was followed in situ by synchrotron X-ray diffraction revealing a three-step reaction mechanism. The asprepared manganese(II) phosphonates were calcined on air. All samples were successfully tested for their suitability as catalyst material in the oxygen evolution reaction. KW - Mechanochemistry KW - In situ KW - XRD PY - 2018 DO - https://doi.org/10.1007/s10853-018-2608-6 SN - 0022-2461 SN - 1573-4803 VL - 53 IS - 19 SP - 13390 EP - 13399 PB - Springer Science + Business Media B.V. AN - OPUS4-45673 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wilke, Manuel A1 - Akhemtova, Irina A1 - Rademann, K. A1 - Emmerling, Franziska T1 - Mechanochemical synthesis of cerium(IV)-phosphonates N2 - The syntheses and crystal structures of two cerium(IV) phosphonates are presented. Cerium(IV) bis(phenylphosphonate) Ce(O3PC6H5)2 1 can be formed from precipitation and mechanochemical reaction, whereas cerium(IV) bis(carboxymethylphosphonate) monohydrate Ce(O3PCH2COOH)2 H2O 2 is only accessible via ball milling. All reactions proceed very fast and are completed within a short time span. In situ measurements for the syntheses of 1 show that the product occurs within seconds or a few minutes, respectively. The structures were solved from powder X-ray diffraction data. KW - In situ studies KW - Mechanochemistry KW - XRD PY - 2018 DO - https://doi.org/10.1007/s10853-018-2507-x SN - 0022-2461 SN - 1573-4803 VL - 53 IS - 19 SP - 13733 EP - 13741 PB - Springer Science + Business Media B.V. AN - OPUS4-45672 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartelmeß, Jürgen A1 - Gawlitza, Kornelia A1 - Kraus, Werner A1 - Chlvi-Iborra, Katherine A1 - Tiebe, Carlo A1 - Noske, Reinhard A1 - Bartholmai, Matthias A1 - Rurack, Knut T1 - Developments Towards a BODIPY-based fluorometric sensing device for multiple hazardous gases N2 - Fluorometric sensing is a versatile approach for trace analysis outside of the laboratory, requiring suitable sensor materials and their integration into sensing devices. The versatility of fluorophores as probes, especially in terms of the possibility to tailor their optical as well as their recognition properties by synthetic modifications in a wide range, renders them as superior active component for the preparation of optical sensing devices. Recent works at BAM in this field include, for example, the detection of nerve gas agents, illustrating impressively the aforementioned benefits of fluorophores in optical sensing applications. In the interdisciplinary project presented here, we target hazardous gases such as ammonia, benzene, and hydrogen sulfide, next to others, which pose a major threat to human health and environmental safety and for which the availability of a sensitive and reliable detection method is highly desirable. The dyes presented follow a “turn-on” fluorescence schematic, which allows for the selective and sensitive detection of the respective gaseous analyte. The immobilization of the probe in polymeric matrices is then the next step toward the fabrication of a prototype device for molecular sensing. Further steps in the project include the assembly of instruments for test-atmosphere generation, the referencing of the sensor system, development and implementation of an optical setup, and the testing of the prototype device under laboratory conditions and in the field. In this presentation, we give an overview over the recent developments on this topic in our groups. Highlights are hydrogen sulfide sensitive, BODIPY based transition metal complexes, which allow for a sensitive as well as selective detection of the toxic gas. In addition, we present a novel class of highly substituted BODIPY derivatives – pocket-BODIPYs – which are of a synthetically high versatility and can readily be modified to create pockets in the periphery of the molecule of defined geometries. This is illustrated on the successful encapsulation of benzene by a pocket-BODIPY derivative, confirmed by X-ray crystallographic analysis as well as by further spectroscopic and analytical methods. T2 - International Conference on Porphyrins and Phthalocyanins (ICPP-10) CY - Munich, Germany DA - 01.07.2018 KW - BODIPY dye KW - Fluorometric sensing KW - Gas sensing PY - 2018 AN - OPUS4-45646 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maurino, V. A1 - Hodoroaba, Vasile-Dan A1 - Pellutiè, L. A1 - Pellegrino, F. A1 - Ortel, Erik A1 - Isopescu, R. T1 - Synthesis of Shape controlled TiO2 N2 - Titanium dioxide is one of the most studied metal oxides due to its chemical, surface, electronic and (photo)catalytic properties, providing this material of multisectorial applications ranging from healthcare, photocatalysis, smart materials with self cleaning and self sterilizing properties and solar energy harvesting. However it is difficult to correlate the functional properties of TiO2 nanomaterials to the properties at single nanoparticle level due to the high polydispersity in shape, size and surface features of the currently available TiO2 nanoparticles (NPs). Although intensive experimental and theoretical studies have been conducted on the reactivity of different surfaces of metal oxides such as TiO2 much less attention is paid on the dependence of functional properties, like photocatalytic activity, dye adsorption, open circuit potential and fill factor in dye sensitized solar cells, on crystal facets in different orientations. One of the goal of SETNanoMetro project was the development of design rules to tune crystal facets of TiO2 NPs in order to optimize and control functional properties. In the present work we have developed a series of design rules in order to obtain sets of anatase TiO2 NPs with low polydispersity and to tune their shape and size by hydrothermal processing of Ti(IV)-Triethanolamine complex in presence of different shape controllers. Through a careful experimental design, a predictive soft model was developed. The model is able to predict the synthesis outcome allowing to tune the shape factor from 5 (prisms) to 1.5 (bipyramids) to 0.2 (platelets). This allows to control the main crystal facets exposed ranging from (100) to (001). Due to the dependence of functional properties of nanomaterials on shape distribution and not only size, the availability of NPs sets with uniform and well defined and tunable shapes can be of paramount relevance in order to produce reference nanomaterials for shape measurement. T2 - NanoWorkshop 2018 (Workshop on reference nanomaterials, current situation and needs: development, measurement, standardization) CY - Berlin, Germany DA - 14.05.2018 KW - Anatase KW - Shape control KW - Hydrothermal synthesis KW - Nanoparticles PY - 2018 AN - OPUS4-45634 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rauscher, H. A1 - Hodoroaba, Vasile-Dan A1 - Mech, A. A1 - Gaillard, C. A1 - Marvin, H. A1 - Wohlleben, W. A1 - Babick, F. A1 - Friedrich, C. M. A1 - Bruengel, R. A1 - Rückert, J. A1 - Ghanem, A. A1 - Weigel, S. T1 - The NanoDefine Decision Framework and NanoDefiner e-Tool: a practical guide to the identification of nanomaterials N2 - The European Commission's recommendation on the definition of nanomaterial [2011/696/EU] is broadly applicable across different regulatory sectors and requires the quantitative size determination of constituent particles in samples down to 1 nm. A material is a nanomaterial if 50 % or more of the particles are in the size range 1-100 nm. The implementation of the definition in a regulatory context challenges measurement methods to reliably identify nanomaterials and ideally also non-nanomaterials as substance or product ingredient as well as in various matrices. The EU FP7 NanoDefine project [www.nanodefine.eu] addressed these challenges by developing a robust, readily implementable and cost-effective measurement strategy to decide for the widest possible range of materials whether it is a nanomaterial or not. It is based on existing and emerging particle measurement techniques evaluated against harmonized, material-dependent performance criteria and by intra- and inter-lab comparisons. Procedures were established to reliably measure the size of particles within 1-100 nm, and beyond, taking into account different shapes, coatings and chemical compositions in industrial materials and consumer products. Case studies prove their applicability for various sectors, including food, pigments and cosmetics. A main outcome is the establishment of an integrated tiered approach including rapid screening (tier 1) and confirmatory methods (tier 2), a decision support flow scheme and a user manual to guide end-users, such as manufacturers, in selecting appropriate methods. Another main product is the “NanoDefiner” e-Tool which implements the flow scheme in a user-friendly software and guides the user in a semi-automated way through the entire decision procedure. It allows a cost-effective selection of appropriate methods for material classification according to the EC's nanomaterial definition and provides a comprehensive report with extensive explanation of all decision steps to arrive at a transparent identification of nanomaterials as well as non-nanomaterials for regulatory purposes. The project has received funding from the European Union’s Seventh Programme for research, technological development and demonstration under grant agreement No 604347. T2 - BAM-PTB Workshop on Reference Nanomaterials CY - Berlin, Germany DA - 14.05.2018 KW - Definition of nanomaterial KW - Regulation PY - 2018 AN - OPUS4-45633 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogl, Jochen A1 - Rosner, M. A1 - Curbera, J. A1 - Peltz, U. A1 - Peplinski, Burkhard T1 - Lead isotope analysis in magic artefacts from the Berlin museums N2 - A set of 59 ancient magical artefacts, mainly made of lead, was selected from the collections of the Staatliche Museen zu Berlin in order to unravel their origins. All the selected artefacts have been studied for their Pb isotope compositions, which covered the whole range of the Mediterranean ore deposits. However, the majority (≈86%) were made of lead matching the small compositional range of the Laurion ore deposits. Only eight out of the 59 artefacts were made of recycled lead or lead from other ore deposits. Additionally, all but two were approximately dated based on their inscriptions. The lead isotopic composition together with information obtained from the inscriptions, the resulting dating, the context of the find and the known history of each item allowed us to gain more detailed information about the origins of these magical artefacts. The Attic provenance of 36 curse tablets was confirmed, whereas for 11 curse tablets previously classified as non-Attic, the provenance was either confirmed and specified (six artefacts) or changed to Attic (five artefacts). Surprisingly, the majority (six out of eight) of the analysed curse tablets from the Egyptian collection showed a lead isotopic composition closely matching that of Laurion. A Laurion-like lead isotopic composition was also observed for three of the four analysed oracular tablets from Dodona. Together with the dating information, this points to Laurion as the major and dominant lead source in the Aegean, at least during the fourth–third century B.C. The few curse tablets from earlier than the fourth–third century B.C. point to the use of multiple and thus isotopically more variable lead sources compared with the Roman times. KW - Lead isotopes KW - Pb isotopes KW - Greek curse tablets KW - Antikensammlung Berlin KW - Ägyptisches Museum Berlin PY - 2018 DO - https://doi.org/10.1007/s12520-016-0445-6 SN - 1866-9557 SN - 1866-9565 VL - 10 IS - 5 SP - 1111 EP - 1127 PB - Springer Verlag CY - Berlin AN - OPUS4-45628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schönhals, Andreas A1 - Frick, B. A1 - Zorn, R. ED - Kremer, Friedrich ED - Loidl, Alois T1 - The scaling of the molecular dynamics of liquid crystals as revealed by broadband dielectric, specific heat, and neutron spectroscopy N2 - A combination of different complementary methods is employed to investigate scaling of the molecular dynamics of two different liquid crystals. Each method is sensitive to different kind of fluctuations and provides therefore a different window to look at the molecular dynamics. In detail, broadband dielectric spectroscopy is combined with specific heat spectroscopy and neutron scattering. As systems the nematic liquid crystal E7 and a discotic liquid crystalline pyrene are considered. First of all it was proven that both systems show all peculiarities which are characteristic for glassy dynamics and the glassy state. Especially for the nematic liquid crystal E7 it could be unambiguously shown by a combination of dielectric and specific heat spectroscopy that the tumbling mode is the underlying motional process responsible for glassy dynamics. Dielectric investigations on the discotic liquid crystalline pyrene reveal that at the phase transition from the plastic crystalline to the hexagonal columnar liquid crystalline phase the molecular dynamics changes from a more strong to fragile temperature dependence of the relaxation rates. Moreover a combination of results obtained by specific heat spectroscopy with structural methods allows an estimation of the length scale relevant for the glass transition. KW - Broadband dielectric spectroscopy KW - Specific heat spectroscopy KW - Rod-like liquid crystals KW - Discotic liquid crystals PY - 2018 UR - https://link.springer.com/content/pdf/10.1007%2F978-3-319-72706-6.pdf SN - 978-3-319-72705-9 SN - 978-3-319-72706-6 DO - https://doi.org/10.1007/978-3-319-72706-6_9 SN - 2190-930X SN - 2190-9318 SP - 279 EP - 306 PB - Springer International publishing AG CY - Cham, Switzerland ET - 1. AN - OPUS4-45624 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -