TY - JOUR A1 - Haist, M. A1 - Link, J. A1 - Nicia, D. A1 - Leinitz, Sarah A1 - Baumert, C. A1 - von Bronk, T. A1 - Cotardo, D. A1 - Eslami Pirharati, M. A1 - Fataei, S. A1 - Garrecht, H. A1 - Gehlen, C. A1 - Hauschildt, I. A1 - Ivanova, I. A1 - Jesinghausen, S. A1 - Klein, C. A1 - Krauss, H.-W. A1 - Lohaus, L. A1 - Lowke, D. A1 - Mazanec, O. A1 - Pawelczyk, S. A1 - Pott, U. A1 - Radebe, N. W. A1 - Riedmiller, J. J. A1 - Schmid, H.-J. A1 - Schmidt, Wolfram A1 - Secrieru, E. A1 - Stephan, D. A1 - Thiedeitz, M. A1 - Wilhelm, M. A1 - Mechtcherine, V. T1 - Interlaboratory study on rheological properties of cement pastes and reference substances: comparability of measurements performed with different rheometers and measurement geometries N2 - This paper presents the results of an interlaboratory study of the rheological properties of cement paste and ultrasound gel as reference substance. The goal was to quantify the comparability and reproducibility of measurements of the Bingham parameters yield stress and plastic viscosity when measured on one specific paste composition and one particular ultrasound gel in different laboratories using different rheometers and measurement geometries. The procedures for both in preparing the cement paste and carrying out the rheological measurements on cement paste and ultrasound gel were carefully defined for all of the study’s participants. Different conversion schemes for comparing the results obtained with the different measurement setups are presented here and critically discussed. The procedure proposed in this paper ensured a reasonable comparability of the results with a coefficient of variation for the yield stress of 27% and for the plastic viscosity of 24%, despite the individual measurement series’ having been performed in different labs with different rheometers and measurement geometries. KW - Rheometry KW - Rheology KW - Interlaboratory test KW - Test setup KW - Testing procedure KW - Cement paste KW - Ultrasound gel PY - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-511220 SN - 1871-6873 VL - 53 IS - 4 SP - 92 PB - Rilem AN - OPUS4-51122 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 U6 - 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 - Renz, F. A1 - Zaba, C. A1 - Roßberg, L. A1 - Jung, S. A1 - Klein, M. A1 - Klingelhöfer, G. A1 - Wünsche, A. A1 - Reinhardt, S. A1 - Menzel, Michael T1 - Spin transition in heptanuclear star-shaped iron(III)-antimony(V) NCS- and CN-bridged compounds N2 - The precursor [FeIII(L)Cl] (LH2 = N,N'-bis(2'-hydroxy-benzyliden)-1,6-diamino-3-azahexane) has been prepared and Mössbauer spectroscopy assigned a high-spin (S = 5/2) state at room temperature. The precursor is combined with the bridging units [SbV(X)6]- (X = CN-, NCS-) to yield star-shaped heptanuclear clusters [(LFeIII-X)6SbV]Cl5. The star-shaped compounds are in general high-spin systems at room temperature. On cooling to 20 K some of the iron(III) centers switch to the low-spin state as indicated by Mössbauer spectroscopy, i.e. multiple electronic transitions. While the cyano-bridged complex performs a multiple spin transition the thiocyanate-compound shows no significant population at both temperatures. KW - Heptanuclear KW - High-spin molecule KW - SbV KW - Multistability KW - Multiple spin transition PY - 2009 U6 - https://doi.org/10.1016/j.poly.2008.12.027 SN - 0277-5387 VL - 28 IS - 9-10 SP - 2036 EP - 2038 PB - Elsevier CY - Amsterdam [u.a.] ; Jena AN - OPUS4-19659 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, X.-d. A1 - Meier, R.J. A1 - Schäferling, Michael A1 - Bange, S. A1 - Lupton, J.M. A1 - Sperber, M. A1 - Wegener, J. A1 - Ondrus, V. A1 - Beifuss, U. A1 - Henne, U. A1 - Klein, C. A1 - Wolfbeis, Otto S. T1 - Two-photon excitation temperature nanosensors based on a conjugated fluorescent polymer doped with an Europium probe N2 - A strongly fluorescent organic semiconducting polymer doped with a highly temperature dependent fluorescent europium(III) complex is converted into a nanosized material that is capable of optically sensing temperature (T) in the range from 0 to 50 °C via two-photon excitation at 720 nm. The nanosensors are prepared from a blue-fluorescent polyfluorene that acts as both a lightharvesting antenna (to capture two-photon energy) and an energy donor in a fluorescence resonance energy transfer (FRET) system. The photonic energy absorbed by the polymer is transferred to the T-sensitive red-luminescent europium complex contained in the nanoparticles. The close spatial proximity of the donor and the acceptor warrants efficient FRET. A poly(ethylene glycol)- co-poly(propylene oxide) block copolymer is also added to render the particles biocompatible. It is shown that T can be calculated from a) the intensity of the luminescence of the europium complex, b) the ratio of the intensities of the red and blue luminescence, or c) the T-dependent luminescence lifetime of the Eu(III) complex. KW - Optical sensor KW - Temperature sensor KW - Nanosensor KW - FRET system PY - 2016 UR - http://onlinelibrary.wiley.com/doi/10.1002/adom.201600601/abstract U6 - https://doi.org/10.1002/adom.201600601 SN - 2195-1071 VL - 4 IS - 11 SP - 1854 EP - 1859 PB - Wiley-VCH CY - Weinheim AN - OPUS4-38737 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Feltin, N. A1 - Crouzier, L. A1 - Delvallée, A. A1 - Pellegrino, F A1 - Maurino, V. A1 - Bartczak, D. A1 - Goenaga-Infante, H. A1 - Taché, O. A1 - Marguet, S. A1 - Testard, F. A1 - Artous, S. A1 - Saint-Antonin, F. A1 - Salzmann, Christoph A1 - Deumer, J. A1 - Gollwitzer, C. A1 - Koops, R. A1 - Sebaïhi, N. A1 - Fontanges, R. A1 - Neuwirth, M. A1 - Bergmann, D. A1 - Hüser, D. A1 - Klein, T. A1 - Hodoroaba, Vasile-Dan T1 - Metrological Protocols for Reaching Reliable and SI-Traceable Size Results for Multi-Modal and Complexly Shaped Reference Nanoparticles N2 - The study described in this paper was conducted in the framework of the European nPSize project (EMPIR program) with the main objective of proposing new reference certified nanomaterials for the market in order to improve the reliability and traceability of nanoparticle size measurements. For this purpose, bimodal populations as well as complexly shaped nanoparticles (bipyramids, cubes, and rods) were synthesized. An inter-laboratory comparison was organized for comparing the size measurements of the selected nanoparticle samples performed with electron microscopy (TEM, SEM, and TSEM), scanning probe microscopy (AFM), or small-angle X-ray scattering (SAXS). The results demonstrate good consistency of the measured size by the different techniques in cases where special care was taken for sample preparation, instrument calibration, and the clear definition of the measurand. For each characterization method, the calibration process is described and a semi-quantitative table grouping the main error sources is proposed for estimating the uncertainties associated with the measurements. Regarding microscopy-based techniques applied to complexly shaped nanoparticles, data dispersion can be observed when the size measurements are affected by the orientation of the nanoparticles on the substrate. For the most complex materials, hybrid approaches combining several complementary techniques were tested, with the outcome being that the reliability of the size results was improved. KW - Certified reference nanomaterials KW - Traceable nanoparticle size measurements; KW - Hybrid metrology KW - Scanning probe microscopy KW - Small-angle X-ray scattering KW - Electron microscopy PY - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-571902 SN - 2079-4991 VL - 13 IS - 6 - Special Issue "Identification and Quantification of Nanomaterials" SP - 1 EP - 25 PB - MDPI CY - Basel, CH AN - OPUS4-57190 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bahlmann, Stefanie A1 - Rübner, Katrin A1 - Meng, Birgit A1 - Hauer, B. A1 - Klein, H. A1 - Müller, C. A1 - Ruppert, J. A1 - Schäfer, S. A1 - Spanka, G. A1 - Wassing, W. A1 - Zunzer, U. T1 - Potenziale des Sekundärstoffeinsatzes im Betonbau - Teilprojekt B1 KW - Nachhaltigkeit KW - Sekundäre Gesteinskörnung KW - Rezyklierte Gesteinskörnung KW - Betonbrechsand KW - Müllverbrennungsasche PY - 2007 SN - 978-3-410-65772-9 SN - 0171-7197 N1 - Geburtsname von Bahlmann, Stefanie: Ramolla, S. - Birth name of Bahlmann, Stefanie: Ramolla, S. IS - 572 SP - 131 EP - 222 PB - Beuth AN - OPUS4-16361 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eichler, Thorsten A1 - Isecke, Bernd A1 - Klein, H.-H. A1 - Schade, A. A1 - Pruckner, F. A1 - Michel, S. T1 - Kathodischer Korrosionsschutz von Stahl in Beton - Instandsetzung des Parkhauses "Am Gericht" in Frankfurt am Main N2 - Die Instandsetzung von Stahlbetonbauteilen bzw.-werken, welche durch chloridinduzierte Korrosion der Bewehrung gefährdet oder bereits geschädigt sind, hat in den letzten Jahrzehnten weltweit an Bedeutung gewonnen. Der kathodische Korrosionsschutz, als elektrochemisches Instandsetzungsverfahren, bildet in diesem Fall eine zuverlässige und oftmals kostengünstige Methode zur Instandsetzung. Am Beispiel des Parkhauses Am Gericht in Frankfurt am Main werden die Durchführung solch einer Maßnahme sowie die Besonderheiten des Verfahrens beschrieben. Es werden die theoretischen Hintergründe erläutert und die praktische Umsetzung sowie zu klärende Detailfragen beschrieben. Die Daten der ersten Depolarisationsmessungen zeigen den aktuellen Zustand der Anlage sowie des Schutzobjektes. KW - Stahlbeton KW - Kathodischer Korrosionsschutz KW - Korrosion KW - Lochkorrosion KW - Instandsetzung KW - Elektrochemische Verfahren PY - 2007 SN - 0005-9900 SN - 1437-1006 VL - 102 IS - 5 SP - 310 EP - 320 PB - Ernst CY - Berlin AN - OPUS4-14769 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Renz, F. A1 - Jung, S. A1 - Klein, M. A1 - Menzel, Michael A1 - Thünemann, Andreas T1 - Molecular switching complexes with iron and tin as central atom N2 - The precursor [FeIII(L)Cl] (LH