TY - CONF A1 - Rades, Steffi A1 - Salge, T. A1 - Unger, Wolfgang A1 - Hodoroaba, Vasile-Dan T1 - Automated feature analysis of nanoparticles by high-resolution transmission scanning electron microscopy and energy dispersive X-ray spectroscopy T2 - EuroNanoForum (ENF) 2015 CY - Riga, Lativa DA - 2015-06-09 PY - 2015 AN - OPUS4-33487 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sobol, Oded A1 - Holzlechner, Gerald A1 - Wirth, Thomas A1 - Nolze, Gert A1 - Böllinghaus, Thomas A1 - Unger, Wolfgang T1 - Investigations of Hydrogen Embrittlement (HE) by Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) T2 - 18. Tagung Festkörperanalytik CY - Vienna, Austria DA - 2015-06-07 PY - 2015 AN - OPUS4-33692 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Holzlechner, Gerald A1 - Sobol, Oded A1 - Straub, Franka A1 - Böllinghaus, Thomas A1 - Unger, Wolfgang T1 - ToF-SIMS as a Metrology Tool to Support Material and Analytical Science T2 - Seminar at MTEC Bangkok CY - Bangkok, Thailand DA - 2015-06-22 PY - 2015 AN - OPUS4-34686 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lange, Nele A1 - Dietrich, Paul A1 - Holzweber, Markus A1 - Lippitz, Andreas A1 - Unger, Wolfgang A1 - Kulak, N. T1 - Functionalization of Silicon Nitride T2 - PhD Retreat 2015 CY - Wandlitz, Germany DA - 2015-06-05 PY - 2015 AN - OPUS4-33486 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Roth, Christina A1 - Schalley, Christoph A. A1 - Unger, Wolfgang T1 - Incorporating mechanically interlocked molecules into crystalline coordination networks on surfaces: Electro-active SURMOFs to translate molecular switching into macroscopic function and devices N2 - We aim at preparing, characterising, and applying SURMOFs incorporating electro-active and -switchable mechanically interlocked molecules such as rotaxanes as the basis of functional devices. Preparation and Positioning Synthesis, purification and analytical characterization of electro-switchable rotaxanes suitable for SURMOF-formation as well as Layer-by-Layer assembly on surfaces. Controlled deposition of electro-active SURMOFs and Layer-by-Layer self-assembled multilayers based on these switchable rotaxanes. Construction of SURMOFs on micro-patterned surfaces. Structural Characterisation and Physico-Chemical Properties Electrochemical characterization of these rotaxanes in solution with cyclic voltammetry, chronoamperometry and impedance spectroscopy. Surface characterization of SURMOFs and multilayers with XPS, NEXAFS, AFM, contact-angle measurements, transmission UV/Vis, ToF-SIMS and – in cooperation with partners from SPP – XRD. Development of ToF-SIMS (also assisted by Principle Component Analysis of the fragment-ion data) as a method for imaging and depth-profiling. Development of an appropriate electrochemical cell to perform cyclic voltammetry, chronoamperometry and impedance spectroscopy with SURMOFS and multilayers as working electrodes in a three-electrode cell. Comparison of the structural and electrochemical properties of the redox-active unit in solution, multilayers and SURMOF focusing on the advantages of SURMOFs. System Integration and Function Demonstration Examination of the usability of the electroactive SURMOFS as optoelectronic switch or data storage device with a focus on the robustness of the system. Usage of the SURMOFs as functional electrodes for electrochemical application. Selective switching of ordered nanostructures to translate molecular motion to macroscopic property changes. T2 - Colloquium of the priority programme "Coordination networks: building blocks for functional systems” SPP 1928 CY - Garching, Germany DA - 30.3.16 KW - SurfMOF KW - XPS KW - NEXAFS KW - Characterization PY - 2016 AN - OPUS4-35867 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Wolfgang T1 - 2-D materials standardization N2 - The implementation of new 2-D materials based technologies in production processes requires the development of quality management tools. These have to be underpinned by appropriate measurements. Consequently there is a need for the development of the metrology for measurement methods, the development of certified reference materials (CRM) and finally standardization. This chain represents the ideal way to practically useful standards. The presentation will give an overview on the main players in the field and summarize the recent status of activities. At the highest level the metrology of chemical characterization of 2D materials is in the scope of the International Meter Convention, specifically the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM). Pre-standardization is an activity field of the Versailles Project on Advanced Materials and Standards (VAMAS). Standardization is mainly addressed by addressed ISO Technical Committees. A summary on available CRMs relevant to the characterization of nano materials has been prepared by BAM. Examples from the work of BAM’s Division 6.1 “Surface Analysis and Interfacial Chemistry” showcasing the characterization of chemically modified graphene surfaces are given and specific needs for the development of metrology are addressed. In the discussion the audience is invited to define specific needs which will be streamlined to the respective bodies! T2 - Science-Industry-Workshop 2D Materials CY - EMPA Akademie, Dübendorf, Switzerland DA - 21.3.16 KW - Standardization KW - Graphene PY - 2016 AN - OPUS4-35866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Roth, C. A1 - Schalley, C. A. A1 - Unger, Wolfgang T1 - Incorporating mechanically interlocked molecules into crystalline coordination networks on surfaces: Electro-active SURMOFs to translate molecular switching into macroscopic function and devices N2 - We aim at preparing, characterising, and applying SURMOFs incorporating electro-active and -switchable mechanically interlocked molecules such as rotaxanes as the basis of functional devices. Preparation and Positioning Synthesis, purification and analytical characterization of electro-switchable rotaxanes suitable for SURMOF-formation as well as Layer-by-Layer assembly on surfaces. Controlled deposition of electro-active SURMOFs and Layer-by-Layer self-assembled multilayers based on these switchable rotaxanes. Construction of SURMOFs on micro-patterned surfaces. Structural Characterisation and Physico-Chemical Properties Electrochemical characterization of these rotaxanes in solution with cyclic voltammetry, chronoamperometry and impedance spectroscopy. Surface characterization of SURMOFs and multilayers with XPS, NEXAFS, AFM, contact-angle measurements, transmission UV/Vis, ToF-SIMS and – in cooperation with partners from SPP – XRD. Development of ToF-SIMS (also assisted by Principle Component Analysis of the fragment-ion data) as a method for imaging and depth-profiling. Development of an appropriate electrochemical cell to perform cyclic voltammetry, chronoamperometry and impedance spectroscopy with SURMOFS and multilayers as working electrodes in a three-electrode cell. Comparison of the structural and electrochemical properties of the redox-active unit in solution, multilayers and SURMOF focusing on the advantages of SURMOFs. System Integration and Function Demonstration Examination of the usability of the electroactive SURMOFS as optoelectronic switch or data storage device with a focus on the robustness of the system. Usage of the SURMOFs as functional electrodes for electrochemical application. Selective switching of ordered nanostructures to translate molecular motion to macroscopic property changes. T2 - Colloquium of the Priority Programme "Coordination Networks: Building Blocks for Functional Systems” SPP 1928 CY - Garching, Germany DA - 30.3.16 KW - SURMOF KW - XPS KW - NEXAFS KW - Characterization PY - 2016 AN - OPUS4-35868 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. A1 - Titscher, Thomas A1 - Hirthammer, Volker A1 - Huschke, Philip A1 - Otto, Peter A1 - Pohl, Christoph T1 - The benefit of mesoscale models for concrete to understand its complex macroscopic behavior N2 - Concrete is one of the most important building materials world wide. The safety of constructions build from concrete is of utmost importance in daily life. As a consequence, accurate predictions of the structural behavior over the entire lifetime of concrete structures are required to ensure a prescribed safety level. A lack of exact models and/or stochastically varying constitutive parameters are compensated by large safety factors. The nonlinear structural performance is strongly related to the constitutive behavior of concrete. Arbitrary complex models can be used to describe the macroscopic constitutive behavior of concrete. The parameters in these models often lack any physical meaning. Consequently, the fitting can only be performed by an inverse analysis. In contrast, models on finer scales are able to simulate the physical phenomena more accurately and are thus better suited to understand the failure mechanisms. In addition, the macroscopically observed strong nonlinearities can at least partially be explained by the direct modeling of the material heterogeneities on finer scales. The presentation discusses several phenomena that are strongly related to the internal microstructure of concrete. This includes the discrepancy between the unique results of a numerical model and the stochastic scatter observed in real experiments. A short discussion on the generation of random mesoscale geometries to model aggregates and mortar matrix explicitly and random fields are given. The strong nonlinearities especially for stresses close to the peak strength are usually the result of failure in the mortar matrix or the interfacial transition zone, whereas the aggregates are inert and often can accurately be modeled by a linear elastic model. The different constitutive properties lead to eigenstresses that strongly in uence the macroscopic behavior. In addition, this effect is even more pronounced when dealing with multiphysics phenomena such as drying, creep and shrinkage, fatigue or thermal problems. It will be demonstrated for several examples that simple models on the fine scale can be superimposed and coupled to obtain a macroscopically nonlinear behavior, where the superposition principle does not hold any longer. Finally, a short discussion on upscaling techniques to couple mesoscale models with large scale structural problems is given. T2 - ECCOMAS 2016 CY - Kreta, Greece DA - 05.06.2016 KW - FEM, concrete, mesoscale PY - 2016 AN - OPUS4-36459 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Wolfgang A1 - Holzlechner, Gerald A1 - Giovannozzi, A. A1 - Portesi, C. A1 - Pelster, A. A1 - Arlinghaus, H. F. A1 - Bunch, J. A1 - Tyler, B. A1 - Pollakowski, B. A1 - Beckhoff, B. T1 - Traceability of PDMS on TiO2 and HDPE substrates by a multi analytical approach T2 - 16th European Conference on Applications of Surface and Interface Analysis (ECASIA 15) CY - Granada, Spain DA - 2015-09-28 PY - 2015 AN - OPUS4-34808 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Wolfgang A1 - Passiu, C. A1 - Paul, D. A1 - Hammond, J. A1 - Venkatraman, N. V. A1 - Bernard, L. A1 - Rossi, A. A1 - Spencer, N. D. T1 - Fabrication, microscopic and spectroscopic characterization of planar, nanopatterned,multi-metallic samples C T2 - 16th European Conference on Applications of Surface and Interface Analysis (ECASIA 15) CY - Granada, Spain DA - 2015-09-28 PY - 2015 AN - OPUS4-34809 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -