TY - CONF A1 - Bonse, Jörn A1 - Kirner, Sabrina V. A1 - Wirth, Thomas A1 - Florian, Camilo A1 - Sturm, Heinz A1 - Spaltmann, Dirk A1 - Krüger, Jörg T1 - Chemical effects during the formation of femtosecond 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 – a fact that is 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 nanometers thick graded oxide layers, consisting mainly of amorphous oxides. Regardless of reduced hardness and limited thickness, this nanostructured surface layer efficiently prevents a direct metal-to-metal contact in the RSTT and may also act as an anchor layer for specific wear-reducing additives contained in the used engine oil. T2 - EMRS Spring Meeting 2019, Symposium V “Laser interactions with materials: from fundamentals to applications" CY - Nice, France DA - 27.05.2019 KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser KW - Oxidation KW - Tribology PY - 2019 AN - OPUS4-48127 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin A1 - Yin, Huajie A1 - Schönhals, Andreas T1 - Characterization of high-performance membrane polymers for gas separation using broadband dielectric spectroscopy N2 - In recent years superglassy polymers exhibiting intrinsic microporosity established a new perspective for a number of applications, especially for gas separation membranes as These polymers Combine extremely high permeabilities with attractive selectivities. The essential factor governing the structure Formation in the solid film or layer is either a contorted rigid Backbone (polymers of intrinsic microporosity - PIMs) or extremely bulky side groups (polynorbornenes and polytricyclonenenes). For a deeper understanding of both types of such high-Performance polymers for gas separation membranes and their further development broadband dielectric spectroscopy (BDS) can provide a substantial contribution. BDS addresses molecular relaxations characterizing the dynamics of the solid polymer as a major factor determining the gas transport properties but also the physical aging behavior which is an essential issue for such polymers. BDS is applied on PIMs where fluctuations of molecular dipoles connected to the backbone can be directly monitored. Furthermore, also polynorbornenes were investigated which carry no dipole moment in their repeat unit - the high resolution of modern equipment allows for the detailed analysis also for very small dielectric losses originating from partially oxidized moieties or marginal catalyst residues. Additionally, from interfacial polarization phenomena, such as Maxwell-Wagner-Sillars (MWS) polarization due to blocking of charge carriers at internal interfacial boundaries on a mesoscopic length scale, valuable information on the intrinsic microporosity and its changes induced by physical aging can be obtained. Finally, also conductivity can be characterized in detail in such polymeric systems revealing contributions of interactions of aromatic moieties (π-π-stacking) or the drift motion of charge carriers. These features also determine the structure formation in the solid state. T2 - 257th ACS National Meeting - Symposium "Transport in Polymer Membranes" CY - Orlando, FL, USA DA - 31.03.2019 KW - polymers KW - gas separation membranes KW - polynorbornenes KW - polymers of intrinsic microporosity KW - dielectric spectroscopy KW - molecular mobility PY - 2019 AN - OPUS4-48142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hahn, Marc Benjamin T1 - Simulational tools in nanoparticle research: Micromagnetics and particle scattering N2 - Simulational tools are applied to investigate the physical properties of nanoparticles. For the description of radioactive gold nanoparticles, particles scattering simulations are performed with the Geant4 monte carlo simulation toolkit. The temperature dependent behaviour of the magnetization dynamics of different magnetic nanoparticles are simulated with the object oriented micormagnetic framework (OOMMF). T2 - NanoBioAp CY - LLanes, Spain DA - 23.05.2019 KW - Monte Carlo KW - Monte-Carlo simulation KW - MCS KW - Nanoparticle KW - AuNP KW - Dosimetry KW - Radioactive NP KW - Microdosimetry KW - Geant4 KW - OOMMF KW - Micromagnetism KW - Simulation KW - Magnetic nanoparticle KW - LLG PY - 2019 AN - OPUS4-48110 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike T1 - Detection of microplastics using thermoanalytical methods  N2 - The presentation summarized the use of thermal analytic methods for the detection of microplastics. T2 - Workshop State of teh art of anylatical methodes for reliable detection of micro- and nanoplastics CY - Ispra, Italy DA - 13.05.2019 KW - microplastics, sampling, sampling techniques, water PY - 2019 AN - OPUS4-48119 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zutta Villate, J. M. A1 - Hahn, Marc Benjamin T1 - Radioactive gold nanoparticles for cancer treatment JF - European physical journal D N2 - Dose enhancement by gold nanoparticles (AuNP) was shown to increase the biological effectiveness of radiation damage in biomolecules and tissue. Most of the current studies focus on external beam therapy on combination with AuNP. Here we present a Monte-Carlo study (Geant4) to characterise radioactive AuNP. Radioactive 198 Au emits beta and gamma rays and is considered for applications with solid tumours. To effectively apply 198 AuNP their energy deposit characteristics have to be determined in terms of intrinsic and extrinsic properties e.g. AuNP diameter, AuNP density, and their clustering behaviour. After each decay process, the energy deposit, inelastic scattering events, kinetic energy spectrum of secondary particles within the AuNP themselves and in a spherical target volume of water up to 1 μm radius were determined. Simulations were performed for AuNP radii ranging from 2.5 nm to 20 nm radius, different cluster sizes and densities. The results show an increase of the energy deposit in the vicinity of the AuNP up to 150 nm. This effect nearly vanishes for distances up to one micron. For the case of AuNP clusters and the same activity, the enhancement of the energy deposit increases with the relative gold mass percentage and therefore can be adjusted by changing AuNP radius or clustering behaviour. KW - Gold KW - Nanoparticle KW - Cancer KW - Monte-Carlo KW - Simulation KW - Cluster PY - 2019 DO - https://doi.org/10.1140/epjd/e2019-90707-x SN - 1434-6060 SN - 1434-6079 VL - 73 IS - 95 SP - 1 EP - 7 PB - Springer CY - Berlin AN - OPUS4-47964 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dittmann, Daniel A1 - Ruhl, A. S. A1 - Jekel, M. A1 - Braun, Ulrike T1 - Spurenstoffadsorption an Aktivkohle – Untersuchungen mit Analysen oberhalb des Siedepunktes N2 - Im Vortrag wird der Ansatz zur Aufklärung von Adsorptionsprozessen, die in der Wasserphase stattgefunden haben, mittels Thermogravimetrie und Zersetzungsgasanalyse vorgestellt. Es wird allgemein gezeigt wie TGA zur Charakterisierung von Aktivkohleoberflächen genutzt werden kann und welche Unterschiede sich in verschiedenen Adsorbat-Systemen zeigen. Im Detail wird die thermische Zersetzung von adsorbiertem Carbamazepin an drei verschiedenen Aktivkohlen präsentiert. T2 - Wasser 2019 CY - Erfurt, Germany DA - 27.05.2019 KW - Aktivkohle KW - Adsorption KW - Carbamazepin KW - Thermogravimetrie PY - 2019 AN - OPUS4-48257 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Braun, Ulrike A1 - Eisentraut, Paul T1 - Mikroplastik als analytische Herausforderung N2 - Der Vortrag beschäftigt sich mit den gängisten Methoden zur Probennahme, -vorbereitung und Detektion von Mikroplastik. Das Zusammenspiel von Fragestellung und Methode wird betont. Es wird auf das Dikussionspapier Analytik des BMBF-Forschungsschwerpunktes Plastik in der Umwelt besonders hingewiesen sowie Bemühungen zur Normierung der Methoden auf deutscher und internationaler Ebene dargestellt. T2 - 18. BfR-Forum Verbraucherschutz: Mikroplastik CY - Berlin, Germany DA - 06.06.2019 KW - Mikroplastik KW - Analyse KW - Normung PY - 2019 AN - OPUS4-48234 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisentraut, Paul A1 - Goedecke, Caroline A1 - Dümichen, E. A1 - Kittner, Maria A1 - Hassanein, Yosri A1 - Jekel, M. A1 - Braun, Ulrike T1 - Ein µ zurück, zwei voran: Komplikationen bei der Mikroplastikdetektion per TED-GC-MS N2 - Die ThermoExtraktionDesorption-Gaschromatografie-Massenspektrometrie (TED-GC-MS) ist die wichtigste Methode der BAM zur Analyse von Mikroplastikpartikeln in Umweltproben. Mit wachsendem Erfahrungsschatz traten Komplikationen auf, bei deren Bewältigung das Analysensystem verbessert werden konnte. Das Poster präsentiert u. a. die Verbesserung der Nachweisgrenzen sowie die Eliminierung von Kontaminationsquellen aus gängigen Probennahmeverfahren. T2 - Tagung der Wasserchemischen Gesellschaft CY - Erfurt, Germany DA - 27.05.2019 KW - Mikroplastik KW - ThermoExtraktionDesorptionGCMS KW - Komplikation PY - 2019 AN - OPUS4-48235 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisentraut, Paul A1 - Goedecke, Caroline A1 - Dümichen, E. A1 - Braun, Ulrike T1 - Detektion von Mikroplastik mittels Thermoextraktion Desorption Gas Chromatographie Massen Spektrometrie (TED-GC-MS) N2 - Das Poster gibt eine kurze Einleitung in die Thematik Mikroplastik in der Umwelt. Das Funktionsprinzip des Verfahrens und einige Kenndaten werden dargestellt. Optimierte Verfahrensparameter werden aufgezählt und Teilergebnisse aus zwei Messkampagnen gezeigt. T2 - Abschlusskonferenz BMBF-Projekt MiWa CY - Karlsruhe, Germany DA - 09.09.2019 KW - Mikroplastik KW - TED-GC-MS KW - Optimierung PY - 2019 AN - OPUS4-49117 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisentraut, Paul A1 - Hassanein, Yosri A1 - Elert, Anna Maria A1 - Braun, Ulrike T1 - Understanding degradation mechanisms of microplastics in environmental samples N2 - Im Vortrag wird die Problematik Mikroplastik eingeführt und ein Probenset aus dem Mittelmeer mit ersten Ergebnissen besprochen. Die Alterung von Polymeren im Umweltkontext sowie Möglichkeiten der Analyse von Polymeralterungsfortschritten werden diskutiert. Die thermoanalytische Methode mit Zersetzungsgasanalytik (TED-GC-MS) wird eingeführt und deren Einsatzmöglichkeiten in der Thematik umrissen. T2 - EuroMech Colloquium 607 Marine Aging of Polymers CY - Brest, France DA - 28.08.2019 KW - Microplastics KW - Tara Mediterranee KW - Polymer aging KW - TED-GC-MS PY - 2019 AN - OPUS4-49110 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -