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Time-resolved X-ray absorption spectroscopy are combined with UV-vis and Raman spectroscopies to study the in situ reduction of Ce(super 4+) to Ce(super 3+) in ethanolic solution with a time resolution of ca.4-5 s. It is observed that high quality results can be obtained simultaneously, thus giving a detailed insight into the mechanisms of the investigated chemical reaction.

The article focuses on the first beam experimental test of a superconductive undulator (SCU14) at the Institute for Synchrotron Radiation storage ring at the Karlsruhe Research Center in Karlsruhe, Germany. SCU14 has been designed by ACCEL Instruments GmbH for nanometer beamline. The experiment has been aimed at demonstrating that the device can be operated under conventional user considerations, which will pave way towards advancement in spectroscopy.

The dynamics of the ignition and extinction of the catalytic partial oxidation (CPO) of methane to hydrogen and carbon monoxide over Pt-Rh/Al(2)O(3) and Pt/Al(2)O(3) were studied in the subsecond timescale using quick-EXAFS with a novel cam-driven X-ray monochromator employing Si(111) and Si(311) crystals. The experiments were performed under reaction conditions in a small fixed-bed capillary reactor. For the first time XAS data were taken with this QEXAFS technique with a Si(311) crystal that opens the energy range up to 35 keV. In addition, both XANES and EXAFS data are shown at the Pt L(3)-edge, allowing to discuss the potential and limitation of this technique in catalysis and related areas. With respect to the noble metal catalysed partial oxidation of methane, several interesting observations were made: structural changes during ignition were-independent of the chosen reaction conditions-significantly faster than during the extinction of the reaction. The dynamic behavior of the catalysts was dependent on the flow conditions and the respective noble metal component(s). Higher reaction gas flow led to a faster ignition process. While the ignition over Pt-Rh/Al(2)O(3) occurred at lower temperature than over Pt/Al(2)O(3), the structural changes during ignition were significantly faster in the latter case. The rate of reduction of the catalyst during ignition was also dependent on the axial position in the fixed-bed. The spectroscopic results provide important insight into the ignition and extinction behavior of the CPO of methane and are complementing results from time-resolved infrared thermography and full field X-ray microscopy studies.