TY - CONF A1 - Nolze, Gert T1 - Simulation of powder diffraction patterns N2 - The theory of powder diffraction simulation is explained at the example of PowderCell, a free-available software of BAM. T2 - PowderCell Users meeting CY - Joinville, Brazil DA - 21.09.2015 KW - Powder diffraction KW - X-ray diffraction KW - Phase analysis KW - Simulation PY - 2015 AN - OPUS4-37789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scherb, T. A1 - Fantin, Andrea A1 - Checcia, S. A1 - Stephan-Scherb, Christiane A1 - Escolástico, S. A1 - Franz, A. A1 - Seeger, J. A1 - Meulenberg, W. A. A1 - d'Acapito, F. A1 - Serra, J. M. T1 - Unravelling the crystal structure of Nd5.8WO12-d and Nd5.7W0.75Mo0.25O12-d mixed ionic electronic conductors N2 - Mixed ionic electronic conducting ceramics Nd6-yWO12-d (d is the Oxygen deficiency) provide excellent stability in harsh environments containing strongly reactive gases such as CO2, CO, H2, H2O or H2S. Due to this chemical stability, they are promising and cost-efficient candidate materials for gas separation, catalytic membrane reactors and protonic ceramic fuel cell technologies. As in La6-yWO12-d, the ionic/electronic transport mechanism in Nd6-yWO12-d is expected to be largely controlled by the crystal structure, the conclusive determination of which is still lacking. This work presents a crystallographic study of Nd5.8WO12-d and molybdenum-substituted Nd5.7W0.75Mo0.25O12-d prepared by the citrate complexation route. High-resolution synchrotron and neutron powder diffraction data were used in combined Rietveld refinements to unravel the crystal structure of Nd5.8WO12-d and Nd5.7W0.75Mo0.25O12-d. Both investigated samples crystallize in a defect fluorite crystal structure with space group Fm3m and doubled unit-cell parameter due to cation ordering. Mo replacesWat bothWyckoff sites 4a and 48h and is evenly distributed, in contrast with La6-yWO12-d. X-ray absorption spectroscopy as a function of partial pressure pO2 in the near-edge regions excludes oxidation state changes of Nd (Nd3+) and W(W6+) in reducing conditions: the enhanced hydrogen permeation, i.e. ambipolar conduction, observed in Mo-substituted Nd6-yWO12-d is therefore explained by the higher Mo reducibility and the creation of additional – disordered – oxygen vacancies. KW - Powder diffraction KW - Mixed conductors KW - X-ray absorption spectroscopy PY - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-514607 VL - 53 SP - 1471 EP - 1483 AN - OPUS4-51460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Batzdorf, Lisa A1 - Zientek, Nicolai A1 - Rump, Doreen A1 - Fischer, Franziska A1 - Maiwald, Michael A1 - Emmerling, Franziska T1 - Make and break - Facile synthesis of cocrystals and comprehensive dissolution studies N2 - Mechanochemistry is increasingly used as a ‘green alternative’ for synthesizing various materials including pharmaceutical cocrystals. Herein, we present the mechanochemical synthesis of three new cocrystals containing the API carbamazepine (cocrystals CBZ:Indometacin 1:1, CBZ:Benzamide 1:1, and CBZ:Nifedipine 1:1). The mechanochemical reaction was investigated in situ documenting a fast and complete reaction within one minute. Online NMR spectroscopy proved the direct influence of the dissolution behaviour of the coformers to the dissolution behaviour of the API carbamazepine. The dissolution behaviour of the organic cocrystals is compared to the behaviour of the pure drug indicating a general applicability of this approach for detailed cocrystal dissolution studies. KW - Cocrystals KW - Carbamazepine KW - Mechanochemistry KW - Powder diffraction KW - Online NMR spectroscopy PY - 2017 U6 - https://doi.org/10.1016/j.molstruc.2016.11.063 SN - 0022-2860 SN - 1872-8014 VL - 1133 SP - 18 EP - 23 AN - OPUS4-38664 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -