TY - JOUR A1 - van der Hout, J. W. A1 - van der Veen, A. M. H. A1 - Ziel, P. R. A1 - Kipphardt, Heinrich A1 - Tuma, Dirk A1 - Maiwald, Michael A1 - Fernández, T. E. A1 - Gómez, C. A1 - Cieciora, D. A1 - Ochman, G. A1 - Dias, F. A1 - Silvino, V. A1 - Macé, T. A1 - Sutour, C. A1 - Marioni, F. A1 - Ackermann, A. A1 - Niederhauser, B. A1 - Fükő, J. A1 - Büki, T. A1 - Szilágyi, Z. N. A1 - Tarhan, T. A1 - Engin, E. T1 - International Comparison Euramet.QM-K111 – Propane in Nitrogen N2 - This key comparison aims to assess the core capabilities of the participants in gas analysis. Such competences include, among others, the capabilities to prepare Primary Standard gas Mixtures (PSMs), perform the necessary purity analysis on the materials used in the gas mixture preparation, the verification of the composition of newly prepared PSMs against existing ones, and the capability of calibrating the composition of a gas mixture. According to the Strategy for Key Comparisons of the Gas Analysis Working Group, this key comparison is classified as an RMO track A key comparison. The artefacts were binary mixtures of propane in nitrogen at a nominal amount-of-substance fraction level of 1000 μmol/mol. The values and uncertainties from the gravimetric gas mixture preparation were used as key comparison reference values (KCRVs). Each transfer standard had its own KCRV. The results are generally good. All results are within ± 1 % of the KCRV. KW - EURAMET.QM-K111 KW - Propane in nitrogen PY - 2017 DO - https://doi.org/10.1088/0026-1394/54/1A/08020 SN - 0026-1394 VL - 54 IS - Technical Supplement SP - 08020, 1 EP - 34 PB - IOP Science AN - OPUS4-44471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schulz, Eduard A1 - Erhard, Anton A1 - Heinrich, W. A1 - Mohr, F. T1 - Nachqualifikation einer Wasserreibbremse mit Ultraschall N2 - Neu entwickelte Gasturbinen werden im Prüffeld mit wechselnden Belastungen beaufschlagt. Dazu wird die Gasturbine mit einer Wasserreibbremse gekoppelt, mit der eine definierte Last erzeugt werden kann. Ursprünglich war die Wasserreibbremse für eine bestimmte Leistung, die den früheren Leistungen der Gasturbine entsprach, ausgelegt worden. Die erste Prüfung fand im Jahr 1975 statt. Da neuere Gasturbinen wesentlich höhere Leistungen erbringen und die vorhandene Wasserreibbremse weiterhin eingesetzt werden sollte, musste eine Nachqualifizierung vorgenommen werden. Das Ziel war die Absicherung auf eine mögliche Sprödbruchgefahr. Zunächst wurde eine Studie zur Prüfbarkeit erstellt. An speziellen Testkörpern wurden im Ultraschallabor der BAM Vorversuche zur Machbarkeit, zur Empfindlichkeitsein-stellung und zur Vorbereitung der Prüfung durchgeführt. Dazu wurden spezielle Gruppenstrahlerprüfköpfe gefertigt und ein an die komplizierte Geometrie der Bremsscheiben angepasster Manipulator gebaut. Ferner wurde, um die Prüfzeiten zu reduzieren, die Software zur Datenerfassung und zur Auswertung angepasst. Im Werk Berlin der Siemens AG wurde in Zusammenarbeit mit der Siemens AG Erlangen eine Ultraschallprüfung mit der Gruppenstahlertechnik der Wasserreibbremse durchgeführt. Überprüft wurde das gesamte Volumen auf axial, radial und tangential beanspruchte Fehler in den Bereichen der Welle und der Bremsscheibe.Die Überprüfung ergab keine relevanten Fehler, so dass die Wasserreibbremse weiterhin eingesetzt werden kann. T2 - Jahrestagung Zerstörungsfreie Materialprüfung 2000 CY - Innsbruck, Österreich DA - 2000-05-29 PY - 2000 UR - http://www.ndt.net/abstract/dgzfp00/data/79.htm SN - 3-931381-32-3 VL - 73 IS - 2 SP - 1(?) EP - 7(?) PB - DGZfP CY - Berlin AN - OPUS4-940 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinrich, F. A1 - Schmidt, C. A1 - Löffler, E. A1 - Menzel, Michael A1 - Grünert, W. T1 - Fe-ZSM-5 Catalysts for the Selective Reduction of NO by Isobutane - The Problem of the Active Sites N2 - Relations between the structure of Fe–ZSM-5 catalysts prepared by interaction of FeCl3 with H–ZSM-5 and their catalytic behavior in the SCR of NO by isobutane were investigated by combining results of catalytic studies (1000 ppm NO, 1000 ppm isobutane, and 2% O2 in He, 30,000 h-1) and of physicochemical characterization (XRD, EXAFS, Mössbauer spectroscopy, TPR, IR, XPS). By variation of the preparation conditions (method of FeCl3 introduction—chemical vapor deposition or solid-state ion exchange, washing intensity, calcination regime) and of the matrix (H–ZSM-5 with normal and high defect density), Fe–ZSM-5 materials with strongly varying properties (aggregation degree of the Fe phase, acidity) were obtained. Significant discrepancies between conclusions derived from EXAFS, TPR, and Mössbauer spectroscopy were ascribed to a preference of Mössbauer spectroscopy for the detection of aggregated phases and a high defectivity of Fe oxide clusters formed upon calcination. The critical step for the preparation of a highly disperse Fe phase is extensive washing after Fe introduction. The catalytic behavior of overexchanged Fe–ZSM-5 materials prepared by interaction of FeCl3 with H–ZSM-5 of normal defect density was not influenced by aggregation of a significant part of the Fe phase. The comparison of their catalytic properties with those of a Fe2O3/H–ZSM-5 mechanical mixture and of catalysts prepared by aqueous ion exchange or by CVD of FeCl3 into H–ZSM-5 of high defect density implies that the particular activity of overexchanged Fe–ZSM-5 arises from minority sites. In these, the Fe ions are probably isolated. Other Fe sites of low nuclearity appear to add to the activity. The poor SCR performance (at a given ability for isobutane activation) of Fe–ZSM-5 prepared with a defective ZSM-5 matrix may indicate that the Fe sites which provi de the particular activity of overexchanged Fe–ZSM-5 require the cooperation of acidic sites. KW - deNOx KW - Hydrocarbons KW - Isobutane KW - Fe-ZSM-5 KW - EXAFS KW - Mössbauer spectroscopy KW - Temperature-programmed reduction PY - 2002 DO - https://doi.org/10.1006/jcat.2002.3775 SN - 0021-9517 SN - 1090-2694 VL - 212 SP - 157 EP - 172 PB - Acad. Press CY - San Diego, Calif. AN - OPUS4-2258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heinrich, F. A1 - Schmidt, C. A1 - Löffler, E. A1 - Menzel, Michael A1 - Grünert, W. T1 - Selective reduction of NO by hydrocarbons with Fe zeolites: Relations between the structure of active Fe sites and catalytic activity T2 - 3rd International Conference on Environmental Catalysis CY - Tokyo, Japan DA - 2001-12-10 PY - 2001 AN - OPUS4-6233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zier, M. A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Radtke, Martin A1 - Munnik, F. T1 - Accurate stopping power determination of 15N ions for hydrogen depth profiling by a combination of ion beams and synchrotron radiation N2 - Hydrogen analysis is of particular importance in thin film technology and it is often necessary to obtain a depth profile. The method with the best depth resolution is NRA using the 6385 keV resonance of the 1H(15N,αγ)12C nuclear reaction. The correct quantification of the depth and concentration scales in the measured hydrogen profiles relies on accurate stopping power values. We present a method to deduce these values from a combination of two techniques: NRA and X-ray reflectometry (XRR). This method is applied to the determination of the stopping power of ~6.4 MeV 15N ions in H-containing amorphous Si-layers (a-Si:H). Density-independent stopping powers at different H concentrations are determined by combining the results from NRA and XRR with an overall uncertainty of 3.3%, showing good agreement with SRIM values. This work shows exemplary the methodology for future evaluation of stopping powers for quality assurance in NRA. KW - Nuclear reaction analysis KW - Hydrogen depth profiling KW - Stopping cross section KW - Linear energy transfer KW - Synchrotron radiation KW - XRR PY - 2012 DO - https://doi.org/10.1016/j.nimb.2011.07.027 SN - 0168-583X SN - 1872-9584 VL - 273 SP - 18 EP - 21 PB - Elsevier CY - Amsterdam AN - OPUS4-25722 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Guerra, M. F. A1 - Calligaro, T. A1 - Radtke, Martin A1 - Reiche, I. A1 - Riesemeier, Heinrich T1 - Fingerprinting ancient gold by measuring Pt with spatially resolved high energy Sy-XRF N2 - Trace elements of ancient gold such as Pt, give fundamental information on the circulation of the metal in the past. In the case of objects from the cultural heritage, the determination of trace elements requires non-destructive point analysis in general. These conditions and the need of good detection limits restrain the number of applicable analytical techniques. After the development of a PIXE set-up with a selective Cu or Zn filter of 75 µm and of a PIXE-XRF set-up using a primary target of As, we tested the possibilities of spatially resolved Sy-XRF to determine Pt in gold alloys. With a Zn filter, PIXE showed a detection limit of 1000 ppm in gold while PIXE-XRF lowers this detection limit down to 80 ppm. This last value being constrained by the resonant Raman effect produced on gold. In order to improve the detection limit of Pt keeping the non-destructiveness and access to point analysis, we developed an analytical protocol for XRF with synchrotron radiation at BESSY II, using the BAMline set-up. The L-lines of Pt were excited by a beam of energy above and below 11.564 keV and measured using a Si(Li) detector with a 50 µm Cu filter. A µ-beam of 100–250 µm2 was used according to the size of the sample. The determination of the Pt content in the samples was carried out by Monte-Carlo simulation and subtraction of Au and Pt spectra obtained on pure standards. The limit of detection for Pt of 20 ppm was determined by using certified standards. The detection limits of a small set of other characteristic elements of gold were also measured using an incident energy of 33 keV. KW - PIXE-XRF KW - Sy-XRF KW - Pt KW - Ancient gold KW - Fingerprinting PY - 2005 DO - https://doi.org/10.1016/j.nimb.2005.06.150 SN - 0168-583X SN - 1872-9584 VL - 240 IS - 1-2 SP - 505 EP - 511 PB - Elsevier CY - Amsterdam AN - OPUS4-14236 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mechler, S. A1 - Schumacher, G. A1 - Koteski, V. A1 - Riesemeier, Heinrich A1 - Schäfers, F. A1 - Mahnke, H.-E. T1 - Local structure and site substitution in amorphous and quasicrystalline Zr-Ti-Ni-(Cu) alloys N2 - Local structures of amorphous and quasicrystalline phases in Zr–Ti–Ni and Zr–Ti–Ni–Cu alloys have been studied by means of x-ray absorption spectroscopy. The amorphous phases show a high degree of icosahedral short-range order. In all investigated systems local order around Cu and Ni atoms was found to be nearly identical pointing to site substitution of Ni by Cu as the reason for an improved glass forming ability when Ni is partly substituted by Cu. The results strengthen an icosahedral cluster based approach for the structure of metallic glasses and indicate the importance of the medium-range order on glass formation. KW - Copper alloys KW - Frustration KW - Glass structure KW - Metallic glasses KW - X-ray absorption spectra PY - 2010 DO - https://doi.org/10.1063/1.3467265 SN - 0003-6951 SN - 1077-3118 VL - 97 IS - 4 SP - 041914-1 - 041914-3 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-22122 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Markötter, H. A1 - Alink, R. A1 - Haußmann, J. A1 - Dittmann, K. A1 - Arlt, Tobias A1 - Wieder, F. A1 - Tötzke, C. A1 - Klages, M. A1 - Reiter, C. A1 - Riesemeier, Heinrich A1 - Scholta, J. A1 - Gerteisen, D. A1 - Banhart, J. A1 - Manke, I. T1 - Visualization of the water distribution in perforated gas diffusion layers by means of synchrotron X-ray radiography N2 - Perforated gas diffusion layers (GDLs) of polymer electrolyte membrane fuel cells (PEMFCs) were investigated by means of in-situ synchrotron X-ray radiography during operation. We found a strong influence of perforations on the water distribution and transport in the investigated Toray TGP-H-090 GDL. The water occurs mainly around the perforations, while the holes themselves show varying water distributions. Some remain dry, while most of them fill up with liquid water after a certain period or might serve as drainage volume for effective water transport. KW - Polymer electrolyte membrane fuel cell (PEMFC) KW - Radiography KW - Synchrotron KW - X-ray imaging KW - Perforated gas diffusion layer (GDL) KW - Water transport PY - 2012 DO - https://doi.org/10.1016/j.ijhydene.2012.01.141 SN - 0360-3199 VL - 37 IS - 9 SP - 7757 EP - 7761 PB - Elsevier CY - Oxford AN - OPUS4-26434 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoch, H. A1 - Wessel, A. A1 - Asche, M. A1 - Baum, D. A1 - Beckmann, F. A1 - Bräunig, P. A1 - Ehrig, Karsten A1 - Mühlethaler, R. A1 - Riesemeier, Heinrich A1 - Staude, Andreas A1 - Stelbrink, B. A1 - Wachmann, E. A1 - Weintraub, P. A1 - Wipfler, B. A1 - Wolff, C. A1 - Zilch, M. T1 - Non-sexual abdominal appendages in adult insects challenge a 300 million year old bauplan N2 - Despite their enormous diversity, the bauplan of adult winged insects (pterygotes) is remarkably conservative since the Lower Devonian: a five-segmented head, a three-segmented thorax with three pairs of walking legs and an eleven-segmented abdomen without any non-sexual appendages 1 and 2. The only known exceptions are the abdominal appendages of adult male sepsid flies on the fourth segment; however, these are also used as copulatory organs and are supposedly maintained through sexual selection [3]. Here, we report a rod-like paired appendage from the third and fourth abdominal segments in adults of the Southeast-Asian Hemiptera taxon Bennini (Figure 1A,B; Supplemental information). These are fully musculated, innervated, and movable and bear highly organized sensory and secretory units. The appendages, termed LASSO (lateral abdominal sensory and secretory organs), are consistent in topology and structure in all species studied and not sexually dimorphic. The existence of these non-sexual abdominal appendages reveals the potential of the 300 million year old conserved bauplan of insects. KW - CT KW - Bauplan KW - Adult insects KW - Abdominal appendages PY - 2014 DO - https://doi.org/10.1016/j.cub.2013.11.040 SN - 0960-9822 SN - 1879-0445 VL - 24 IS - 1 SP - R16 EP - R17 PB - Cell Press CY - Cambridge, Mass. AN - OPUS4-30034 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hmood, F. J. A1 - Günster, Jens A1 - Heinrich, J. T1 - Sintering and piezoelectric properties of K0.5Na0.5NbO3 glass microspheres N2 - Laser-fused K0.5Na0.5NbO3 (KNN) powder of 75% transparent fraction has been sintered by pressureless sintering, spark plasma sintering (SPS), and hot isostatic pressing (HIP). The laser-fused KNN has a fictive temperature of 503 °C and an onset crystallization temperature of around 529 °C. The results have shown that sintering of the laser-fused KNN powder utilizing the viscous flow of the transparent microspheres (amorphous content)–at the kinetic window (26 °C)–is possible. The highest yield relative density is around 83% at a sintering temperature of 525 °C and at a sintering pressure of 280 MPa. Limited density has been reached because of formation of crystalline surface layers around the amorphous areas. The samples hipped at 525 °C have low piezoelectric coefficient d33 of 5 pC/N because of the residual porosity that led to early dielectric breakdown during the polarization. The sintering behavior, the resulting microstructure as well as the measured properties will be discussed. KW - KNN KW - Glass microspheres PY - 2015 DO - https://doi.org/10.1016/j.jeurceramsoc.2015.07.035 SN - 0955-2219 SN - 1873-619X VL - 35 IS - 15 SP - 4143 EP - 4151 PB - Elsevier Ltd. CY - Oxford AN - OPUS4-34958 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lange, T. A1 - Neher, F. A1 - Klemm, E. A1 - Heinrich, Sebastian A1 - Balcazar Pust, Emilio A1 - Liebner, Christian A1 - Hieronymus, Hartmut T1 - Heterogeneous catalysis meets micro reactors: Partial oxidations in the explosion regime N2 - Investigations on primary, secondary and tertiary explosion protection have been performed for micro reactors with slit-like channels which are coated with catalyst. Ethene/oxygen mixtures have been used as model gas mixtures representing explosion group IIB (DIN EN ISO 16852). It could be shown that the explosion regime can be significantly reduced when using micro reactors (primary explosion protection). Furthermore, safe Operation inside the explosion regime is possible with micro reactors (secondary explosion protection), but, at certain conditions thermal runaway and ignition of detonations are possible. An unexpected behaviour has been found, because thermal runaway occurred when Volumetrie flow rate was increased. This behaviour is completely opposite to that of multi tube fixed bed reactors which show an increase of safety when increasing volumetric flow rate. Micro reactors can be constructed pressure-resistant even when detonations occur inside (tertiary explosion protection). For the example of o-xylene oxidation it could be shown that space time yield can be increased significantly when entering explosion regime. T2 - DGMK International conference - Selective oxidation and functionalization: Classical and alternative routes and sources CY - Berlin, Germany DA - 13.10.2014 PY - 2014 SN - 978-3-941721-44-9 VL - 2014-3 SP - 97 EP - 105 AN - OPUS4-31759 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönhals, Andreas A1 - Goering, Harald A1 - Costa, F. R. A1 - Wagenknecht, U. A1 - Heinrich, G. T1 - Dielectric properties of nanocomposites based on polyethylene and layered double hydroxide N2 - Nanocomposites with a predominantly exfoliated morphology were prepared by melt blending of organically modified doubled layered hydroxide (LDH) and low density polyethylene (PE). The prepared materials were investigated by differential scanning calorimetry (DSC) and in detail by dielectric spectroscopy. The DSC experiments show that the degree of crystallinity decreases linearly with increasing content of the LDH. The extrapolation of this dependence to zero results in a limiting concentration of ca. 50 wt % LDH were the crystallization of PE is completely suppressed by the nanofiller. The dielectric response of pure polyethylene shows different weak relaxation processes. The intensity of dynamic glass transition (β-relaxation) increases with the concentration of LDH. This is attributed to the increasing concentration of the exchanged anion dodecyl benzene sulfonate (SDBS). The SDBS molecules are strongly adsorbed at the exfoliated LDH layers. Therefore, a detailed analysis of the β-relaxation provides information about the structure and the molecular dynamics in the interfacial region between the exfoliated LDH layers and the polyethylene matrix. This analysis shows that the β-relaxation region consists of two processes: both of them obey glassy dynamics. The difference in corresponding Vogel (ideal glass transition) temperatures is about 30 K. The relaxation process at lower frequency is assigned to polyethylene segments with a reduced molecular mobility close to LDH layers. The process at higher frequencies is related to polyethylene segments in a farer distance for the surface of the nanofiller. In the nanocomposite materials an additional process due to Maxwell-Wagner-Sillars (MWS) polarization was observed. The time constant of this MWS process can be correlated with characteristic length scales in nanocomposites and therefore provides additional information on dispersion and delamination/exfoliation of the LDH layers in these materials. PY - 2009 DO - https://doi.org/10.1021/ma900077w SN - 0024-9297 SN - 1520-5835 VL - 42 IS - 12 SP - 4165 EP - 4174 PB - American Chemical Society CY - Washington, DC AN - OPUS4-19594 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zabler, S. A1 - Rueda, A. A1 - Rack, A. A1 - Riesemeier, Heinrich A1 - Zaslansky, P. A1 - Manke, I. A1 - Garcia-Moreno, F. A1 - Banhart, J. T1 - Coarsening of grain-refined semi-solid Al-Ge32 alloy: X-ray microtomography and in situ radiography KW - Microtomography KW - Radiography KW - 2D/3D imageanalysis KW - Technical binary alloys KW - LSW PY - 2007 DO - https://doi.org/10.1016/j.actamat.2007.05.028 SN - 1359-6454 SN - 1873-2453 VL - 55 IS - 15 SP - 5045 EP - 5055 PB - Elsevier Science CY - Kidlington AN - OPUS4-20583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Wang, D. A1 - Costa, F. R. A1 - Leuteritz, A. A1 - Purohit, Purv A1 - Schönhals, Andreas A1 - Vyalikh, A. A1 - Scheler, U. A1 - Wagenknecht, U. A1 - Kutlu, B. A1 - Heinrich, G. ED - Mittal, V. T1 - Polyolefin nanocomposites with layered double hydroxides PY - 2010 SN - 978-1-4398-1454-3 SP - 225 EP - 245 PB - CRC Press AN - OPUS4-23039 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Unger, Wolfgang A1 - Schwarz, F. A1 - Heinrich, Thomas A1 - Kaufmann, J. O. A1 - Lippitz, Andreas A1 - Puttreddy, R. A1 - Rissanen, K. A1 - Schalley, C. A. T1 - Photocontrolled on-surface pseudorotaxane formation with well-ordered macrocycle multilayers N2 - The photoinduced pseudorotaxane formation between a photoresponsive axle and a tetralactam macrocycle was investigated in solution and on glass surfaces with immobilized multilayers of macrocycles. In the course of this reaction, a novel photoswitchable binding station with azobenzene as the photoswitchable unit and diketopiperazine as the binding station was synthesized and studied by NMR and UV/Vis spectroscopy. Glass surfaces have been functionalized with pyridine-terminated SAMs and subsequently withmultilayers of macrocycles through layer-by-layer self assembly. A preferred orientation of the macrocycles could be confirmed by NEXAFS spectroscopy. The photocontrolled Deposition of the axle into the surface-bound macrocycle-multilayers was monitored by UV/Vis spectroscopy and led to an increase of the molecular order, as indicated by more substantial linear dichroism effects in angle-resolved NEXAFS spectra. KW - Well-ordered macrocycle multilayers KW - XPS KW - NEXAFS PY - 2016 DO - https://doi.org/10.1002/chem.201603156 SN - 0947-6539 SN - 1521-3765 VL - 22 IS - 40 SP - 14383 EP - 14389 PB - Wiley-VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-38270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schwarz, F. A1 - Heinrich, Thomas A1 - Lippitz, Andreas A1 - Unger, Wolfgang A1 - Schalley, C. T1 - A photoswitchable rotaxane operating in monolayers on solid support N2 - A novel photoswitchable rotaxane was synthesised and its switching behaviour in solution was analysed with NMR and UV-Vis. A monolayer of rotaxanes was deposited on glass surfaces and the on-surface photoswitching was investigated. Angle-resolved NEXAFS spectra revealed a preferential orientation that reversibly changes upon switching. KW - XPS KW - NEXAFS KW - Photoswitchable rotaxane KW - Self assembly PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-386814 DO - https://doi.org/10.1039/c6cc08586e SN - 0022-4936 SN - 1364-548X SN - 0009-241x SN - 1359-7345 VL - 52 IS - 100 SP - 14458 EP - 14461 PB - Royal Society of Chemistry (RSC) AN - OPUS4-38681 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhou, Z. A1 - Han, Q. A1 - Wang, D. A1 - Macé, T. A1 - Kipphardt, Heinrich A1 - Maiwald, Michael A1 - Tuma, Dirk A1 - Uehara, S. A1 - Akima, D. A1 - Shimosaka, T. A1 - Jung, J. A1 - Oh, S.-H. A1 - van der Veen, A. A1 - van Wijk, J.I.T. A1 - Ziel, P. R. A1 - Konopelko, L. A1 - Valkova, M. A1 - Mogale, D.M. A1 - Botha, A. A1 - Brewer, P. A1 - Murugan, A. A1 - Minnaro, M.D. A1 - Miller, M. A1 - Guenther, F. A1 - Kelly, M.E. T1 - CCQM K101 Final report international comparison CCQM-K101:Oxygen in nitrogen-a track B comparison and that the matrix contains argon N2 - This key comparison aims to assess the capabilities of the participants to determine the amount-of-substance fraction oxygen in nitrogen. The GAWG has classified this as a track B comparison, due to the unexpected 50 μmol/mol argon mole fraction content of the transfer standards, which effects the achievable performance of some measurement techniques such a GC-TCD. The separation of oxygen and argon is challenging, and not all systems in use are equally well designed for it. As this analytical challenge due to a substantial fraction of argon in the transfer standards became a reality, the Gas Analysis Working Group (GAWG) decided to qualify this key comparison as a regular key comparison and not as a core comparison, which may be used to support calibration and measurement capabilities (CMCs) for oxygen in nitrogen, or for oxygen in nitrogen mixtures containing argon only (see also the section on support to CMCs). KW - CCQM-K101 KW - Gas analysis PY - 2016 UR - http://iopscience.iop.org/article/10.1088/0026-1394/53/1A/08013 SN - 1681-7575 SN - 0026-1394 VL - 53 IS - Techn Suppl SP - 08013, 1 EP - 71 PB - IOP publishing AN - OPUS4-40013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lozano-Martín, D. A1 - Pazoki, F. A1 - Kipphardt, Heinrich A1 - Khanipour, P. A1 - Tuma, Dirk A1 - Horillo, A. A1 - Chamorro, C. R. T1 - Thermodynamic (p, ρ, T) characterization of a reference high-calorific natural gas mixture when hydrogen is added up to 20 % (mol/mol) N2 - The injection of hydrogen into the natural-gas grid is an alternative during the process of a gradual decarbonization of the heat and power supply. When dealing with hydrogen-enriched natural gas mixtures, the performance of the reference equations of state habitually used for natural gas should be validated by using high-precision experimental thermophysical data from multicomponent reference mixtures prepared with the lowest possible uncertainty in composition. In this work, we present experimental density data for an 11-compound high-calorific (hydrogen-free) natural gas mixture and for two derived hydrogen-enriched natural gas mixtures prepared by adding (10 and 20) mol-% of hydrogen to the original standard natural gas mixture. The three mixtures were prepared gravimetrically according to ISO 6142–1 for maximum precision in their composition and thus qualify for reference materials. A single-sinker densimeter was used to determine the density of the mixtures from (250–350) K and up to 20 MPa. The experimental density results of this work have been compared to the densities calculated by three different reference equations of state for natural gas related mixtures: the AGA8-DC92 EoS, the GERG-2008 EoS, and an improved version of the GERG-2008 EoS. While relative deviations of the experimental density data for the hydrogen-free natural gas mixture are always within the claimed uncertainty of the three considered equations of state, larger deviations can be observed for the hydrogen-enriched natural gas mixtures from any of the three equations of state, especially for the lowest temperature and the highest pressures. KW - Hydrogen-enriched natural gas KW - Single-sinker densimeter KW - High-pressure density KW - Equations of state PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-604742 DO - https://doi.org/10.1016/j.ijhydene.2024.05.028 SN - 0360-3199 VL - 70 SP - 118 EP - 135 PB - Elsevier BV CY - Amsterdam AN - OPUS4-60474 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cabral, A.R. A1 - Radtke, Martin A1 - Munnik, F. A1 - Lehmann, B. A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Tupinambá, M. A1 - Kwitko-Ribeiro, R. T1 - Iodine in alluvial platinum-palladium nuggets: evidence for biogenic precious-metal fixation N2 - Synchrotron radiation-induced X-ray fluorescence (SR-XRF) spectrometry was applied to determine iodine concentrations in alluvial Pt–Pd aggregates with delicate morphological features from Córrego Bom Sucesso, Minas Gerais, Brazil. The millimetre-sized botryoidal and rod-shaped grains of alluvial Pt–Pd–Hg intermetallic compounds have surprisingly high concentrations of iodine, in the range from 10 to ~ 120 μg/g. Because iodine is a strongly biophile element, known to be enriched in peatlands and plant remains in soils by microbial activity, its concentration in the Pt–Pd nuggets suggests biogenic precious-metal fixation in the aqueous alluvial milieu. Biogenic and inorganic processes, such as bioreduction and electrochemical metal accretion, could mutually have contributed to the growth of nanoparticles, formed on organic templates, to millimetric Pt–Pd nuggets. KW - Lodine KW - Pt-Pd nuggets KW - Córrego Bom Sucesso KW - Minas Gerais KW - Brazil PY - 2011 DO - https://doi.org/10.1016/j.chemgeo.2010.12.003 SN - 0009-2541 SN - 1872-6836 VL - 281 IS - 1-2 SP - 125 EP - 132 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-23174 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ordavo, I. A1 - Ihle, S. A1 - Arkadiev, V. A1 - Scharf, Oliver A1 - Soltau, H. A1 - Bjeoumikhov, A. A1 - Bjeoumikhova, S. A1 - Buzanich, Günter A1 - Gubzhokov, R. A1 - Günther, A. A1 - Hartmann, R. A1 - Holl, P. A1 - Kimmel, N. A1 - Kühbacher, M. A1 - Lang, M. A1 - Langhoff, N. A1 - Liebel, A. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Schaller, G. A1 - Schopper, F. A1 - Strüder, L. A1 - Thamm, C. A1 - Wedell, R. T1 - A new pnCCD-based color X-ray camera for fast spatial and energy-resolved measurements N2 - We present a new high resolution X-ray imager based on a pnCCD detector and a polycapillary optics. The properties of the pnCCD like high quantum efficiency, high energy resolution and radiation hardness are maintained, while color corrected polycapillary lenses are used to direct the fluorescence photons from every spot on a sample to a corresponding pixel on the detector. The camera is sensitive to photons from 3 to 40 keV with still 30% quantum efficiency at 20 keV. The pnCCD is operated in split frame mode allowing a high frame rate of 400 Hz with an energy resolution of 152 eV for Mn Kα (5.9 keV) at 450 kcps. In single-photon counting mode (SPC), the time, energy and position of every fluorescence photon is recorded for every frame. A dedicated software enables the visualization of the elements distribution in real time without the need of post-processing the data. A description of the key components including detector, X-ray optics and camera is given. First experiments show the capability of the camera to perform fast full-field X-Ray Fluorescence (FF-XRF) for element analysis. The imaging performance with a magnifying optics (3×) has also been successfully tested. KW - X-ray CCD camera KW - pnCCD KW - Fast X-ray imaging KW - XRF KW - Full-field X-ray fluorescence KW - Elemental analysis KW - High quantum efficiency KW - High energy resolution KW - Polycapillary optics PY - 2011 DO - https://doi.org/10.1016/j.nima.2011.05.080 SN - 0168-9002 SN - 0167-5087 VL - 654 SP - 250 EP - 257 PB - North-Holland CY - Amsterdam AN - OPUS4-24370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -