Chemie Ingenieur TechnikVolume 79, Issue 9 p. 1311-1311 PosterFree Access Über den Einfluss von Ba und Pt auf CeO2 als Modell für NOx-Speicher-Reduktions-Katalysatoren M. O. Symalla Dipl.-Ing., M. O. Symalla Dipl.-Ing. symalla@ct.chemie.tu-darmstadt.de Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorA. Drochner Dr., A. Drochner Dr. Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorH. Vogel Prof. Dr., H. Vogel Prof. Dr. Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorS. Philipp Dr., S. Philipp Dr. Umicore AG & Co. KG, Rodenbacher Chaussee 4, D-63403 HanauSearch for more papers by this authorS. Eckhoff Dr., S. Eckhoff Dr. Umicore AG & Co. KG, Rodenbacher Chaussee 4, D-63403 HanauSearch for more papers by this authorW. Müller Dipl.-Ing., W. Müller Dipl.-Ing. Umicore AG & Co. KG, Rodenbacher Chaussee 4, D-63403 HanauSearch for more papers by this author M. O. Symalla Dipl.-Ing., M. O. Symalla Dipl.-Ing. symalla@ct.chemie.tu-darmstadt.de Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorA. Drochner Dr., A. Drochner Dr. Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorH. Vogel Prof. Dr., H. Vogel Prof. Dr. Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorS. Philipp Dr., S. Philipp Dr. Umicore AG & Co. KG, Rodenbacher Chaussee 4, D-63403 HanauSearch for more papers by this authorS. Eckhoff Dr., S. Eckhoff Dr. Umicore AG & Co. KG, Rodenbacher Chaussee 4, D-63403 HanauSearch for more papers by this authorW. Müller Dipl.-Ing., W. Müller Dipl.-Ing. Umicore AG & Co. KG, Rodenbacher Chaussee 4, D-63403 HanauSearch for more papers by this author First published: 18 September 2007 https://doi.org/10.1002/cite.200750275AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume79, Issue9Special Issue: ProcessNet Jahrestagung 2007September, 2007Pages 1311-1311 RelatedInformation

The thermal ageing and reactivation of Ba/CeO 2 and Ba/Al 2 O 3 based NO x -storage/ reduction (NSR) catalysts was studied on model catalysts and catalyst systems at the engine. The mixed oxides BaAl 2 O 4 and BaCeO 3 , which lower the storage activity, are formed during ageing above 850 °C and 900 °C, respectively. Interestingly, the decomposition of BaCeO 3 in an atmosphere containing H 2 O/NO 2 leads again to NO x -storage active species, as evidenced by comparison of fresh, aged and reactivated Pt-Ba/CeO 2 based model catalysts. This can be technically exploited, particularly for the Ba/CeO 2 catalysts, as reactivation studies on thermally aged Ba/CeO 2 and Ba/Al 2 O 3 based NSR catalysts on an engine bench showed. An on-board reactivation procedure is presented, that improved the performance of a thermally aged catalyst significantly.

Differences in the NOx storage-reduction (NSR) behavior of Pt/Ba/CeO2 and Pt/Ba/Al2O3 have been identified and traced to their different chemical and structural properties. The results show that Pt/Ba/CeO2 exhibits inferior NOx storage and, particularly, reduction (regeneration) activity compared to the Al2O3 supported catalyst. The incomplete reduction of the stored NOx-species in Pt/Ba/CeO2 seems to be caused by a faster and more profound reoxidation of Pt particles during the lean period as evidenced by in situ X-ray absorption spectroscopy. Interestingly, the reduction activity could be significantly improved by a pre-reduction step at mild conditions. Exposure of the Pt/Ba/CeO2 catalyst to reducing H2 atmosphere in the temperature range 300–500°C lead to a moderate increase of Pt particle size which beneficially influenced the regeneration activity. In contrast, pre-reduction at temperatures above 500°C was unfavorable and resulted in a severe decrease of the regeneration activity, probably due to migration of the partially reduced CeO2 onto the surface of Pt particles.

Chemie Ingenieur TechnikVolume 78, Issue 9 p. 1249-1250 PosterFree Access IR-Studie zur Nitrit- und Nitratbildung während der NOx-Adsorption an den NSR-Katalysator-Komponenten BaO/CeO2 M. O. Symalla, M. O. Symalla symalla@ct.chemie.tu-darmstadt.de Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorA. Drochner, A. Drochner Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorH. Vogel, H. Vogel Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorS. Philipp, S. Philipp Umicore AG & Co. KG, Rodenbacher Chausse 4, D-63403 HanauSearch for more papers by this authorS. Eckhoff, S. Eckhoff Umicore AG & Co. KG, Rodenbacher Chausse 4, D-63403 HanauSearch for more papers by this authorW. Müller, W. Müller Umicore AG & Co. KG, Rodenbacher Chausse 4, D-63403 HanauSearch for more papers by this author M. O. Symalla, M. O. Symalla symalla@ct.chemie.tu-darmstadt.de Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorA. Drochner, A. Drochner Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorH. Vogel, H. Vogel Technische Universität Darmstadt, Ernst-Berl-Institut für Technische und Makromolekulare Chemie, Petersenstraße 20, D-64287 DarmstadtSearch for more papers by this authorS. Philipp, S. Philipp Umicore AG & Co. KG, Rodenbacher Chausse 4, D-63403 HanauSearch for more papers by this authorS. Eckhoff, S. Eckhoff Umicore AG & Co. KG, Rodenbacher Chausse 4, D-63403 HanauSearch for more papers by this authorW. Müller, W. Müller Umicore AG & Co. KG, Rodenbacher Chausse 4, D-63403 HanauSearch for more papers by this author First published: 06 September 2006 https://doi.org/10.1002/cite.200650317AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume78, Issue9Special Issue: GVC/DECHEMA-Jahrestagungen 2006 mit 24. DECHEMA-Jahrestagung der BiotechnologenSeptember, 2006Pages 1249-1250 ReferencesRelatedInformation

In vitro studies demonstrating the induction of programmed cell death by cytotoxic drugs used in anticancer chemotherapy suggested that antileukemic treatment eliminates leukemia cells by apoptosis. We therefore analyzed apoptosis induction and activation of apoptosis signaling molecules in patients receiving remission induction treatment for AML and ALL during the initial phase of leukemia cell reduction. A coexistence of distinct populations of CD34(+) and CD34(-) leukemia cells could be identified. During chemotherapy, CD34(+) leukemia cells were more rapidly depleted than CD34(-) cells. Furthermore, a significant increase in leukemia cell apoptosis ex vivo was detected in CD34(+) cells, while no such increase was observed in the CD34(-) subpopulation, suggesting that CD34(+) leukemia cells are the main targets for apoptosis induction through antileukemic treatment. No alterations in Bax and Bcl-2 expression were found during in vivo chemotherapy, and CD95 expression and sensitivity remained low, indicating the induction of apoptosis independent of the CD95 system or regulation of protein levels of Bax and Bcl-2. The data suggest that analysis of leukemia cell subpopulations is required for further identification of apoptosis signaling molecules relevant for response to treatment and assessment of drug efficacy in vivo and in vitro.

The selective reduction of NO with propene in the presence of oxygen over a Pt/alumina catalyst has been investigated using TAP and model gas equipment. Experiments with different gas compositions (stoichiometric and overstoichiometric with respect to the complete oxidation of propene) were carried out at temperatures between 473 and 673 K. Additionally, the NO decomposition on reduced and oxidised Pt/alumina was studied. It is shown that N-2 is generated due to NO dissociation and following recombination of N-adatoms. Associatively adsorbed NO needs to be present on the surface to form N2O.

This paper reports on the investigation of the effect of noble metal precursor and support oxide on their catalytic activity for the conversion of diesel exhaust gas components. The noble metal precursors used in this investigation were hexachloroplatinic acid, platinum nitrate, and tetraammine platinum(II) hydroxide. As support metal oxides zirconia, a base metal doped alumina, alumina, and titania were used. Catalysts were prepared from all combinations of precursors and supports and were tested in an integral model gas test reactor both in the fresh and in the aged state. The catalysts were also characterized by various techniques including BET surface area, CO chemisorption, XRD, and TEM. The results indicate that the catalyst prepared from the tetraammine platinum(II) hydroxide precursor on the base metal doped alumina support shows the highest activity for the conversion of the gaseous exhaust components.