TY - CONF A1 - Hilpert, U. A1 - Bartscher, M. A1 - Neugebauer, M. A1 - Goebbels, Jürgen A1 - Weidemann, Gerd A1 - Bellon, Carsten T1 - Simulation-aided computed tomography (CT) for dimensional measurements N2 - Carrying out dimensional measurements by CT means assessing coordinates in space. CT must therefore be treated as a coordinate measuring technique similar to optical or tactile Coordinate Measuring Machines (CMMs). The well-established standards and guidelines for the acceptance- and verificationtesting of CMMs require the use of calibrated reference standards to achieve measurement machine characteristics. Hence, transferring these concepts from coordinate metrology to CT, a dedicated CT-specific reference standard was designed, manufactured and calibrated using a tactile CMM. For comparison purposes, a CAD model was created by reverse engineering using the calibration data. The calibrated model was fed into a virtual CT and the measurement process was simulated. The reference standard was measured by micro-CT. By comparing the characteristics of the measurement output of CT and the output gained from simulation, the influences of measurement artefacts can be judged, for the first time, in analogy to existing Guidelines of coordinate metrology. T2 - DIR 2007 - International Symposium on Digital industrial Radiology and Computed Tomography CY - Lyon, France DA - 25.06.2007 KW - Computed tomography KW - X-ray KW - Simulation KW - Coordinate metrology PY - 2007 UR - http://www.ndt.net/article/dir2007/papers/12.pdf SP - Paper 6, 1 EP - 15 AN - OPUS4-37045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nusser, K. A1 - Mosbauer, T. A1 - Schneider, G. J. A1 - Brandt, K. A1 - Weidemann, Gerd A1 - Goebbels, Jürgen A1 - Riesemeier, Heinrich A1 - Göritz, D. T1 - Silica dispersion in styrene butadiene rubber composites studied by synchrotron tomography N2 - By means of synchrotron X-ray computed tomography, model composites consisting of silica and styrene–butadiene rubber were studied with a very high spatial resolution. By our analysis technique we were able to determine the nano- and micro dispersion from the experimental results by our numerical analysis. These results are discussed with respect to crucial advantages of the generically 3-dimensional tomography technique as compared to 2-dimensional methods. Our quantitative analysis of the 3d images demonstrates that in the case of our model composites the filler dispersion is good, independent on the filler concentration. Our new 3-dimensional results evidence that considering only 2-d pictures may lead to ambiguities that can lead to wrong conclusions. KW - X-ray tomography KW - Silica KW - Styrene butadiene rubber KW - Dispersion PY - 2012 DO - https://doi.org/10.1016/j.jnoncrysol.2011.10.009 SN - 0022-3093 VL - 358 IS - 3 SP - 557 EP - 563 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-26105 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidemann, Gerd A1 - Stadie, R. A1 - Goebbels, Jürgen A1 - Hillemeier, B. T1 - Computed tomography study of fibre reinforced autoclaved aerated concrete PY - 2008 SN - 0025-5300 VL - 50 IS - 5 SP - 278 EP - 285 PB - Hanser CY - München AN - OPUS4-22882 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neugebauer, M. A1 - Hilpert, U. A1 - Bartscher, M. A1 - Gerwien, N. A1 - Kunz, S. A1 - Neumann, F. A1 - Goebbels, Jürgen A1 - Weidemann, Gerd T1 - Ein geometrisches Nomal zur Prüfung von Röntgen-Mikro-Computertomografiemesssystemen KW - Geometrische Normale KW - Röntgen-Mikro-Computertomografie KW - Dimensionelles Messen KW - Messgeräteprüfung KW - Geometrical standard KW - X-ray micro-computertomography KW - Dimensional measurement KW - Instrument testing PY - 2007 SN - 0340-837X SN - 0178-2312 SN - 0171-8096 VL - 74 IS - 11 SP - 565 EP - 571 PB - Oldenbourg CY - München AN - OPUS4-22881 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Osterloh, Kurt A1 - Zscherpel, Uwe A1 - Rädel, Christoph A1 - Weidemann, Gerd A1 - Meinel, Dietmar A1 - Goebbels, Jürgen A1 - Ewert, Uwe A1 - Hasenstab, A. A1 - Bücherl, T. T1 - Durchstrahlungsprüfung von Holz T2 - DGZfP-Jahrestagung 2007 CY - Fürth, Deutschland DA - 2007-05-14 KW - Digitale Radiographie KW - Tomographie KW - Spaltneutronen KW - Neutronenradiographie PY - 2007 SN - 978-3-931381-98-1 IS - DGZfP-BB 104 (Vortrag 40) SP - 1 EP - 12 AN - OPUS4-20717 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kamenz, C. A1 - Weidemann, Gerd T1 - Heavy metal - A contrasting substance for micro-tomographical visualization of scorpion book lungs N2 - Remarkable results obtained while searching for suitable contrasting agents for tomographical imaging are presented. Book lungs, the respiratory organs of scorpions (Scorpiones, Arachnida), served as challenging objects in terms of fragility and preparatory requirements, as well in terms of size differences between the entire organ and its functional subunits (the lamellae). The problem of tissue contrast was investigated using various metals, but most successfully addressed using osmium. Gaseous osmium tetroxide exposure with subsequent ethanol treatment yielded the best results. A constant and thorough staining of the book lungs was achieved, easing book-lung visualization using 3D-reconstructions from µCT scans. KW - Osmium tetroxide KW - muCT KW - X-ray KW - Contrast KW - Respiratory organ PY - 2009 DO - https://doi.org/10.1016/j.micron.2009.05.007 SN - 0047-7206 SN - 0968-4328 VL - 40 IS - 8 SP - 911 EP - 917 PB - Pergamon Press CY - Oxford AN - OPUS4-20095 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rack, A. A1 - Riesemeier, Heinrich A1 - Zabler, S. A1 - Weitkamp, T. A1 - Müller, Bernd R. A1 - Weidemann, Gerd A1 - Modregger, P. A1 - Banhart, J. A1 - Helfen, L. A1 - Danilewsky, A.N. A1 - Gräber, H.G. A1 - Heldele, R. A1 - Mayzel, B. A1 - Goebbels, Jürgen A1 - Baumbach, T. ED - Stuart R. Stock, T1 - The high-resolution synchrotron-based imaging stations at the BAMline (BESSY) and TopoTomo (ANKA) N2 - The BAMline at the BESSY light source in Berlin and the TopoTomo beamline at the ANKA synchrotron facility in Karlsruhe (both Germany) operate in the hard X-ray regime (above 6 keV) with similiar photon flux density. For typical imaging applications, a double multilayer monochromator or a filtered white beam is used. In order to optimise the field of view and the resolution of the available indirect pixel detectors, different optical systems have been installed, adapted, respectively, to a large field of view (macroscope) and to high spatial resolution (microscope). They can be combined with different camera systems, ranging from 16-bit dynamic range slow-scan CCDs to fast CMOS cameras. The spatial resolution can be brought substantially beyond the micrometer limit by using a Bragg magnifier. The moderate flux of both beamlines compared to other 3rd generation light sources is compensated by a dedicated scintillator concept. For selected applications, X-ray beam collimation has proven to be a reliable approach to increase the available photon flux density. Absorption contrast, phase contrast, holotomography and refraction-enhanced imaging are used depending on the application. Additionally, at the TopoTomo beamline digital white beam synchrotron topography is performed, using the digital X-ray pixel detectors installed. KW - Microtomography KW - Non-destructive evaluation KW - Coherent imaging KW - X-ray refraction KW - X-ray phase contrast KW - Synchrotron-CT KW - Synchrotron instrumentation KW - Scintillator KW - Bragg magnification KW - Holotomography KW - X-ray topography PY - 2008 DO - https://doi.org/10.1117/12.793721 SN - 0277-786X VL - 7078 SP - 70780X-1 - 70780X-9 AN - OPUS4-18296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rack, A. A1 - Zabler, S. A1 - Müller, Bernd R. A1 - Riesemeier, Heinrich A1 - Weidemann, Gerd A1 - Lange, Axel A1 - Goebbels, Jürgen A1 - Hentschel, Manfred P. A1 - Görner, Wolf T1 - High resolution synchrotron-based radiography and tomography using hard X-rays at the BAMline (BESSY II) N2 - The use of high brilliance and partial coherent synchrotron light for radiography and computed tomography (CT) allows to image micro-structured, multi-component specimens with different contrast modes and resolutions up to submicrometer range. This is of high interest for materials research, life science and non-destructive evaluation applications. An imaging setup for microtomography and radiography installed at BESSY II (a third generation synchrotron light source located in Berlin, Germany) as part of its first hard X-ray beamline (BAMline) can now be used for absorption, refraction as well as phase contrast — dedicated to inhouse research and applications by external users. Monochromatic synchrotron light between 6 keV and 80 keV is attained via a fully automated double multilayer monochromator. For imaging applications the synchrotron beam transmitted by the sample is converted with a scintillator into visible light. By use of microscope optics this luminescence image is then projected onto, e.g., a CCD chip. Several scintillating materials are used in order to optimise the performance of the detector system. Different optical systems are available for imaging ranging from a larger field of view and moderate resolutions (macroscope — up to 14 mm x 14 mm field of view) to high resolution (microscope — down to 0.35 μm pixel size), offering magnifications from 1.8× to 40×. Additionally asymmetric cut Bragg crystals in front of the scintillator can be used for a further magnification in one dimension by a factor of about 20. Slow and fast cameras are available, with up to 16 bit dynamic range. We show the suitability of the setup for numerous applications from materials research and life science. KW - Microtomography KW - Non-destructive evaluation KW - Synchrotron instrumentation KW - Coherent imaging KW - X-ray refraction KW - Phase contrast KW - Holotomography KW - Synchrotron-CT KW - Scintillator KW - Bragg magnification PY - 2008 DO - https://doi.org/10.1016/j.nima.2007.11.020 SN - 0168-9002 SN - 0167-5087 VL - 586 IS - 2 SP - 327 EP - 344 PB - North-Holland CY - Amsterdam AN - OPUS4-17738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rack, A. A1 - Zabler, S. A1 - Riesemeier, Heinrich A1 - Weidemann, Gerd A1 - Müller, Bernd R. A1 - Helfen, L. A1 - Stiller, M. A1 - Knabe, C. A1 - Goebbels, Jürgen A1 - Banhart, J. T1 - Nondestructive 3D insights into foamy metals and bioregenerative ceramics KW - X-ray Computed Tomography KW - Metal foams KW - Bioregenerative ceramics PY - 2008 UR - http://www.helmholtz-berlin.de/media/media/oea/web/pr_webseite/druckschriften/infos/bessy/highlights2007.pdf#page=34 SN - 1611-6127 SP - 34 EP - 35 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-17538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weidemann, Gerd T1 - Fibre reinforced autocloved aerated concrete studied by computed tomography T2 - International Symposium on Digital Radiography and Computed Tomography CY - Lyon, France DA - 2007-06-25 PY - 2007 AN - OPUS4-15960 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -