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CO is found to be oxidized by non-dissociatively adsorbed NO in O2-containing atmosphere over -Al2O3 supported Rh, Ru and their Sn-alloys at 473 K. Reaction between adsorbed N and O to NO seems to lead to low conversion of NO to N2 in an O2-containing atmosphere.
NO - Rh, Ru Sn 473 . NO N2.相似文献
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Chang SL Stetsko YP Tang MT Lee YR Sun WH Yabashi M Ishikawa T 《Physical review letters》2005,94(17):174801
X-ray back diffraction from monolithic two silicon crystal plates of 25-150 microm thickness and a 40-150 microm gap using synchrotron radiation of energy resolution DeltaE = 0.36 meV at 14.4388 keV clearly show resonance fringes inside the energy gap and the total-reflection range for the (12 4 0) reflection. This cavity resonance results from the coherent interaction between the x-ray wave fields generated by the two plates with a gap smaller than the x-ray coherence length. This finding opens up new opportunities for high-resolution and phase-contrast x-ray studies, and may lead to new developments in x-ray optics. 相似文献
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Horiba K Taguchi M Chainani A Takata Y Ikenaga E Miwa D Nishino Y Tamasaku K Awaji M Takeuchi A Yabashi M Namatame H Taniguchi M Kumigashira H Oshima M Lippmaa M Kawasaki M Koinuma H Kobayashi K Ishikawa T Shin S 《Physical review letters》2004,93(23):236401
Using hard x-ray (HX; hnu=5.95 keV) synchrotron photoemission spectroscopy (PES), we study the intrinsic electronic structure of La(1-x)Sr(x)MnO(3) (LSMO) thin films. Comparison of Mn 2p core-levels with soft x-ray (SX; hnu approximately 1000 eV) PES shows a clear additional well-screened feature only in HX PES. Takeoff-angle dependent data indicate its bulk (> or =20 A) character. The doping and temperature dependence track the ferromagnetism and metallicity of the LSMO series. Cluster model calculations including charge transfer from doping-induced states show good agreement, confirming this picture of bulk properties reflected in Mn 2p core-levels using HX PES. 相似文献
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M. Yamaga T. Inoue S. Yabashi M. Honda J.-P. R. Wells K. Shimamura 《辐射效应与固体损伤》2013,168(6-12):977-982
Electron paramagnetic resonance (EPR) spectra of Ce 3+ in LiLuF 4 (LLF) and LiSr 0.8 Ca 0.2 AlF 6 (LSCAF) observed at low temperatures (<20 v K) show that the Ce 3+ centers have tetragonal and pseudo-trigonal symmetry with ( g , g )=(2.751, 1.467) and (2.14, 0.80), respectively. The EPR lines of Ce 3+ in LSCAF are inhomogeneously broadened by different Ce 3+ configurations which correspond to the random occupation of the second nearest neighbor cation sites by Ca 2+ and Sr 2+ and/or charge compensators. These EPR results indicate that the Ce 3+ centers in LLF and LSCAF are associated with substitution of Ce 3+ for Lu 3+ with eight-fold coordination and Sr 2+ /Ca 2+ with six-fold coordination, respectively. Fourier transform infrared absorption has been used to measure transitions between the 2 F 5/2 ground state and the 2 F 7/2 multiplet of Ce 3+ in LLF at 10 v K. The optical absorption and luminescence of Ce 3+ :LLF and Ce 3+ :LSCAF in the UV range are strongly polarized. The energy levels and polarization dependence of the optical transitions can be accounted for in terms of the crystal field potential experienced by the Ce 3+ ions under the action of the different point group symmetries. 相似文献
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Ohtsuki T Chainani A Eguchi R Matsunami M Takata Y Taguchi M Nishino Y Tamasaku K Yabashi M Ishikawa T Oura M Senba Y Ohashi H Shin S 《Physical review letters》2011,106(4):047602
We study the surface and bulk electronic structure of the room-temperature ferromagnet Co∶TiO(2) anatase films using soft- and hard-x-ray photoemission spectroscopy with probe sensitivities of ~1 and ~10 nm, respectively. We obtain direct evidence of metallic Ti(3+) states in the bulk, which get suppressed to give a surface semiconductor, thus indicating the difference in electronic structure between surface and bulk. X-ray absorption and resonant photoemission spectroscopy reveal Ti(3+) electrons at the Fermi level (E(F)) and high-spin Co(2+) electrons occurring away from E(F). The results show the importance of the charge neutrality condition: Co(2+)+V(O)(2-)+2Ti(4+)?Co(2+)+2Ti(3+) (V(O) is oxygen vacancy), which gives rise to the elusive Ti 3d carriers mediating ferromagnetism via the Co 3d-O 2p-Ti 3d exchange interaction pathway of the occupied orbitals. 相似文献
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Hikosaka Y Fushitani M Matsuda A Tseng CM Hishikawa A Shigemasa E Nagasono M Tono K Togashi T Ohashi H Kimura H Senba Y Yabashi M Ishikawa T 《Physical review letters》2010,105(13):133001
Photoelectron spectroscopy has been performed to study the multiphoton double ionization of Ar in an intense extreme ultraviolet laser field (hν ~ 21 eV, ~ 5 TW/cm2), by using a free electron laser (FEL). Three distinct peaks identified in the observed photoelectron spectra clearly show that the double ionization proceeds sequentially via the formation of Ar(+): Ar+hν→Ar (+) + e? and Ar2(+) + 2hν→Ar(+) + e?. Shot-by-shot recording of the photoelectron spectra allows simultaneous monitoring of FEL spectrum and the multiphoton process for each FEL pulse, revealing that the two-photon ionization from Ar(+) is significantly enhanced by intermediate resonances in Ar(+). 相似文献
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Yabashi M Hastings JB Zolotorev MS Mimura H Yumoto H Matsuyama S Yamauchi K Ishikawa T 《Physical review letters》2006,97(8):084802
An experimental scheme to realize single-shot spectrometry for the diagnostics of x-ray free-electron lasers (XFELs) is presented. The combination of an ultraprecisely figured mirror and a perfect crystal form a simple, high-precision spectrometer that can cover an energy range from a few eV to a hundred eV with high resolution. The application of the spectrometer to determine XFEL pulse widths was investigated theoretically and experimentally. It has been shown that the present system can determine pulse widths from sub-fs to ps in a single shot even for spontaneous radiation. The system can be easily extended to even shorter pulses. 相似文献
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Motohiro Suzuki Yuichi Inubushi Makina Yabashi Tetsuya Ishikawa 《Journal of synchrotron radiation》2014,21(3):466-472
A diamond phase retarder was applied to control the polarization states of a hard X‐ray free‐electron laser (XFEL) in the photon energy range 5–20 keV. The horizontal polarization of the XFEL beam generated from the planar undulators of the SPring‐8 Angstrom Compact Free‐Electron Laser (SACLA) was converted into vertical or circular polarization of either helicity by adjusting the angular offset of the diamond crystal from the exact Bragg condition. Using a 1.5 mm‐thick crystal, a high degree of circular polarization, 97%, was obtained for 11.56 keV monochromatic X‐rays, whereas the degree of vertical polarization was 67%, both of which agreed with the estimations including the energy bandwidth of the Si 111 beamline monochromator. 相似文献