TY - CONF A1 - Petrov, Sergej A1 - Neumann, Patrick P. A1 - Werner, Klaus-Dieter A1 - Lazik, D. A1 - Bartholmai, Matthias T1 - Concept for investigating mechanical impacts on distributed subsurface gas monitoring N2 - A multifunctional sensor in line shape was developed and introduced in previous work for measuring of gas concentrations, temperature change, and strain. A current field study focuses on a spatially distributed monitoring of subsurface CO2 gas storage sites in near real time. Mechanical impacts, e.g., caused by construction work, denudation, and seismic activity, can affect the integrity of underground gas storage sites. Thermal or moisture impacts, e.g., caused by weather conditions, can influence the gas distribution behavior. In this paper, we briefly describe the setup of a CO2 injection soil test field. This setup contains actuating elements for the investigation of mechanical and thermal impacts on distributed subsurface gas monitoring. A concept is given for evaluating these impacts and first experimental results are presented. T2 - 32nd Danubia-Adria Symposium on advances in experimental mechanics CY - Starý Smokovec, Slovakia DA - 22.09.2015 PY - 2015 DO - https://doi.org/10.1016/j.matpr.2016.03.060 SN - 2214-7853 VL - 3 IS - 4 SP - 1124 EP - 1128 PB - Elsevier Science CY - Zilina AN - OPUS4-34489 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Senoner, Mathias A1 - Maaßdorf, A. A1 - Rooch, Heidemarie A1 - Österle, Werner A1 - Malcher, M. A1 - Schmidt, M. A1 - Kollmer, F. A1 - Paul, D. A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Unger, Wolfgang T1 - Lateral resolution of nanoscaled images delivered by surface-analytical instruments: application of the BAM-L200 certified reference material and related ISO standards N2 - The certified reference material BAM-L200, a nanoscale stripe pattern for length calibration and specification of lateral resolution, is described. BAM-L200 is prepared from a cross-sectioned epitaxially grown layer stack of AlxGa1–xAs and InxGa1–xAs on a GaAs substrate. The surface of BAM-L200 provides a flat pattern with stripe widths ranging down to 1 nm. Calibration distances, grating periods and stripe widths have been certified by TEM with traceability to the length unit. The combination of gratings, isolated narrow stripes and sharp edges of wide stripes offers plenty of options for the determination of lateral resolution, sharpness and calibration of length scale at selected settings of imaging surface-analytical instruments. The feasibility of the reference material for an analysis of the lateral resolution is demonstrated in detail by evaluation of ToF-SIMS, AES and EDX images. Other applications developed in the community are summarized, too. BAM-L200 fully supports the implementation of the revised International Standard ISO 18516 (in preparation) which is based on knowledge outlined in the Technical Report ISO/TR 19319:2013. KW - AES KW - BAM-L200 KW - CRM KW - EDX KW - Imaging KW - Lateral resolution KW - Sharpness KW - Standardisation KW - STXM KW - ToF-SIMS KW - XPEEM KW - XPS KW - Certified reference material KW - Imaging surface analysis PY - 2015 DO - https://doi.org/10.1007/s00216-014-8135-7 SN - 1618-2642 SN - 1618-2650 VL - 407 IS - 11 SP - 3211 EP - 3217 PB - Springer CY - Berlin AN - OPUS4-33033 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Österle, Werner A1 - Dmitriev, A.I. A1 - Gradt, Thomas A1 - Häusler, Ines A1 - Hammouri, Basem A1 - Morales Guzman, Pablo Israel A1 - Wetzel, B. A1 - Yigit, D. A1 - Zhang, G. T1 - Exploring the beneficial role of tribofilms formed from an epoxy-based hybrid nanocomposite N2 - The composition and nanostructure of a beneficial tribofilm formed during sliding of a hybrid nanocomposite against steel were characterized comprehensively. A similar nanostructure was produced by high energy ball milling of the three identified tribofilm constituents: silica, hematite and graphite. By supplying powders to a pin-on-disc test it has been shown that neither silica, nor hematite, nor a mixture of both provide the low coefficient of friction (COF) observed for the hybrid composite. Only if graphite was blended with the oxides, the low COF was obtained. Thus, a film of finely dispersed stable inorganic wear products containing 15 vol% graphite provides low friction and wear in the considered case. KW - TEM KW - Nanocomposite KW - Tribofilm KW - Ball milling KW - Pin-on-disc test PY - 2015 DO - https://doi.org/10.1016/j.triboint.2015.03.006 SN - 0301-679X VL - 88 SP - 126 EP - 134 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-33035 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hachmöller, O. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Aichler, M. A1 - Radtke, Martin A1 - Dietrich, D. A1 - Schwamborn, K. A1 - Lutz, L. A1 - Werner, M. A1 - Sperling, M. A1 - Walch, A. A1 - Karst, U. T1 - Elemental bioimaging and speciation analysis for the investigation of Wilsons disease using μXRF and XANES N2 - A liver biopsy specimen from a Wilson’s disease (WD) patient was analyzed by means of micro-X-ray fluorescence (mXRF) spectroscopy to determine the elemental distribution. First, bench-top mXRF was utilized for a coarse scan of the sample under laboratory conditions. The resulting distribution maps of copper and iron enabled the determination of a region of interest (ROI) for further analysis. In order to obtain more detailed elemental information, this ROI was analyzed by synchrotron radiation (SR)-based mXRF with a beam size of 4 mm offering a resolution at the cellular level. Distribution maps of additional elements to copper and iron like zinc and manganese were obtained due to a higher sensitivity of SR-mXRF. In addition to this, X-ray absorption near edge structure spectroscopy (XANES) was performed to identify the oxidation states of copper in WD. This speciation analysis indicated a mixture of copper(I) and copper(II) within the WD liver tissue. KW - progressive hepatolenticular degeneration KW - mXRF Micro-X-ray fluorescence spectroscopy KW - XANES X-ray absorption near edge structure spectroscopy PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-360811 DO - https://doi.org/10.1039/C6MT00001K SN - 1756-5901 SN - 1756-591X PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-36081 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Österle, Werner A1 - Urban, Ingrid A1 - Severin, D. A1 - Trepte, S. T1 - Analyse von Reibschichten auf Bremsbelägen N2 - Die volle Leistung einer auf Reibung basierenden Bremse wird erst nach einem Einlaufvorgang erreicht. Dieser ist notwendig, um auf Belag und Scheibe eine sogenannte Reibschicht aufzubauen. Da diese Zwischenschicht das Reibungsverhalten des Systems maßgeblich bestimmt, ist es wichtig, sich Klarheit über ihre chemische Zusammensetzung, Mikrostruktur und die daraus resultierenden Eigenschaften zu verschaffen. Als Basismaterial diente ein phenolharzgebundener Belag Jurid 57-62, der mit verschiedenen Parametern (Flächenpressung und Umdrehungsgeschwindigkeit) gegen eine Stahlscheibe getestet wurde. Es wurden Dauerbremsungen von jeweils einer Stunde bzw. bis zu einem maximalen Belagverschleiß von 1 mm simuliert, wobei die Entwicklung der Reibzahl und die Oberflächentemperatur der Scheibe registriert wurde. Zur Analyse der Reibschichten auf dem Bremsbelag wurden mehrere Methoden parallel angewandt. So wurden Verschleißpartikel, die aus der Reibschicht stammen, gesammelt bzw. abgekratzt und nach Dispergieren auf Kohlefolien direkt im Transmissionselektronenmikros-kop (TEM) untersucht. Ferner wurden von einigen ausgesuchten Belagproben Mikrotom-schnitte sowie dünne Querschnittsfolien für die TEM-Untersuchung präpariert, um den Verbund Reibschicht-Grundmaterial darstellen zu können. Als Ergänzung wurden ferner oberflächenmorphologische und –analytische Verfahren wie REM/EDX und ESCA eingesetzt. Die Ergebnisse deuten darauf hin, dass die Reibschicht nanokristallin ist, und dass fast alle anorganischen Bestandteile des Bremsbelags sowie Eisenoxid von der Bremsscheibe in sehr fein verteilter Form vorliegen. Bei Belägen ohne Metallanteil bildet eine Barium-Eisen-Sulfatphase offenbar die Grundstruktur der Reibschicht, während auf eisenhaltigen Belägen Eisenoxid dominierend ist. Die nanokristalline Mikrostruktur entsteht, ähnlich wie beim mechanischen Legieren, durch einen Mahlvorgang von Verschleißpartikeln zwischen den Reibpartnern. Bei Überlastung des Belags tritt Zersetzung der Polymer-Bindephase ein, was zu einem raschen Anstieg der Verschleißrate führt. KW - Bremsbelag KW - Reibschicht KW - Reibungskoeffizient KW - Oberflächenanalyse KW - Transmissionselektronenmikroskopie PY - 2000 SN - 0933-5137 VL - 31 SP - 708 EP - 711 PB - Whiley VCH CY - Weinheim AN - OPUS4-38542 LA - deu 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 - JOUR A1 - Cant, D. J. H. A1 - Minelli, C. A1 - Sparnacci, K. A1 - Müller, Anja A1 - Kalbe, H. A1 - Stoger-Pollach, M. A1 - Unger, Wolfgang A1 - Werner, W. S. M. A1 - Shard, A. G. T1 - Surface-Energy Control and Characterization of Nanoparticle Coatings N2 - Accurate and reproducible measurement of the structure and properties of high-value nanoparticles is extremely important for their commercialization. A significant proportion of engineered nanoparticle systems consist of some form of nominally core-shell structure, whether by design or unintentionally. Often, these do not form an ideal core-shell structure, with typical deviations including polydispersity of the core or shell, uneven or incomplete shells, noncentral cores, and others. Such systems may be created with or without intent, and in either case an understanding of the conditions for formation of such particles is desirable. Precise determination of the structure, composition, size, and shell thickness of such particles can prove challenging without the use of a suitable range of characterization techniques. Here, the authors present two such polymer core-shell nanoparticle systems, consisting of polytetrafluoroethylene cores coated with a range of thicknesses of either polymethylmethacrylate or polystyrene. By consideration of surface energy, it is shown that these particles are expected to possess distinctly differing coating structures, with the polystyrene coating being incomplete. A comprehensive characterization of these systems is demonstrated, using a selection of complementary techniques including scanning electron microscopy, scanning transmission electron microscopy, thermogravimetric analysis, dynamic light scattering, differential centrifugal sedimentation, and X-ray photoelectron spectroscopy. By combining the results provided by these techniques, it is possible to achieve superior characterization and understanding of the particle structure than could be obtained by considering results separately. KW - Nanoparticles KW - Core-shell KW - XPS KW - Size KW - Thickness KW - Damage PY - 2020 DO - https://doi.org/10.1021/acs.jpcc.0c02161 VL - 124 IS - 20 SP - 11200 EP - 11211 PB - ACS CY - Washington DC AN - OPUS4-50899 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Petrov, Sergej A1 - Neumann, Patrick P. A1 - Werner, Klaus-Dieter A1 - Wosniok, Aleksander A1 - Lazik, D. A1 - Bartholmai, Matthias ED - Nicoletto, G. ED - Pastrama, S.D. ED - Emri, I. T1 - Concept for investigating mechanical and thermal impacts on distributed subsurface gas monitoring N2 - A multifunctional sensor in line shape was developed and introduced in previous work for measuring of gas concentrations, temperature change, and strain. A current field study focuses on a spatially distributed monitoring of subsurface CO 2 gas storage sites in near real time. Mechanical impacts, e.g., caused by construction work, denudation, and seismic activity, can affect the integrity of underground gas storage sites. Thermal or moisture impacts, e.g., caused by weather conditions, can influence the gas Distribution behavior. In this paper, we briefly describe the setup of a CO 2 injection soil test field. This setup contains actuating elements for the investigation of mechanical and thermal impacts on distributed subsurface gas monitoring. A concept is given for evaluating these impacts and first experimental results are presented. T2 - 32nd DANUBIA ADRIA SYMPOSIUM on Advances in Experimental Mechanics CY - Starý Smokovec, Slovakia DA - 22.09.2015 KW - Linear sensor KW - Distributed sensor KW - Monitoring of CO 2 KW - Subsurface monitoring KW - Gas storage areas KW - Membrane-based gas sensing KW - Fibre optical sensing PY - 2016 DO - https://doi.org/10.1016/j.matpr.2016.03.060 SN - 2214-7853 VL - 3 IS - 4 SP - 1124 EP - 1128 PB - Elsevier Ltd. AN - OPUS4-35688 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppe, Enrico A1 - Augustin, D. A1 - Bartholmai, Matthias A1 - Daum, Werner T1 - Air-based multi-hop sensor network for the localization of persons N2 - In this work an air-based sensor network for the localization of persons at extensive areas is presented. The developed network consists of a localization device which the person is wearing (BodyGuard-System), a mobile relay station in the air, and a base station. All three parts communicate with the same radio chip. The BodyGuard-System is an inertial navigation system which was developed for localization in difficult environments with high accuracy and low measurement uncertainty. To increase the range of the system, a multi-hop network was built up. The measured data of the BodyGuard-System and the mobile relay station is visualized on a PC in the base station. This multi-hop network is necessary for example for fire department missions. T2 - EuroSensors 2014, 28th European Conference on Solid-State Transducers CY - Brescia, Italy DA - 07.09.2014 KW - WSN KW - Mesh routing KW - Air-based KW - Multi-hop KW - Localization PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-324294 DO - https://doi.org/10.1016/j.proeng.2014.11.540 SN - 1877-7058 VL - 87 SP - 528 EP - 531 PB - Elsevier CY - Amsterdam [u.a.] AN - OPUS4-32429 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grulke, E. A. A1 - Yamamoto, K. A1 - Kumagai, K. A1 - Häusler, Ines A1 - Österle, Werner A1 - Ortel, Erik A1 - Hodoroaba, Vasile-Dan A1 - Brown, S. C. A1 - Chan, C. A1 - Zheng, J. A1 - Yamamoto, K. A1 - Yashiki, K. A1 - Song, N. W. A1 - Kim, Y. H. A1 - Stefaniak, A. B. A1 - Schwegler-Berry, D. A1 - Coleman, V. A. A1 - Jämting, Å. K. A1 - Herrmann, J. A1 - Arakawa, T. A1 - Burchett, W. W. A1 - Lambert, J. W. A1 - Stromberg, A. J. T1 - Size and shape distributions of primary crystallites in titania aggregates N2 - The primary crystallite size of titania powder relates to its properties in a number of applications. Transmission electron microscopy was used in this interlaboratory comparison (ILC) to measure primary crystallite size and shape distributions for a commercial aggregated titania powder. Data of four size descriptors and two shape descriptors were evaluated across nine laboratories. Data repeatability and reproducibility was evaluated by analysis of variance. One-third of the laboratory pairs had similar size descriptor data, but 83% of the pairs had similar aspect ratio data. Scale descriptor distributions were generally unimodal and were well-described by lognormal reference models. Shape descriptor distributions were multi-modal but data visualization plots demonstrated that the Weibull distribution was preferred to the normal distribution. For the equivalent circular diameter size descriptor, measurement uncertainties of the lognormal distribution scale and width parameters were 9.5% and 22%, respectively. For the aspect ratio shape descriptor, the measurement uncertainties of the Weibull distribution scale and width parameters were 7.0% and 26%, respectively. Both measurement uncertainty estimates and data visualizations should be used to analyze size and shape distributions of particles on the nanoscale. KW - Measurement uncertainty KW - Size distribution KW - Shape distribution KW - TEM KW - Titania PY - 2017 DO - https://doi.org/10.1016/j.apt.2017.03.027 SN - 0921-8831 VL - 28 IS - 7 SP - 1647 EP - 1659 PB - Elsevier B.V. AN - OPUS4-40478 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -