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31.
32.
K. Bormann 《Fresenius' Journal of Analytical Chemistry》1967,230(3):236
Ohne Zusammenfassung 相似文献
33.
34.
K. Bormann 《Fresenius' Journal of Analytical Chemistry》1967,232(5):382
Ohne Zusammenfassung 相似文献
35.
W. Schmidt W. Sternik D. Ceauescu H. Wagner J. Malur H. Berge K. Bormann B. R. Glutz M. Olivier M. Müller D. Klockow H. Monien H. G. Eulenhöeer H. Sorantin G. Schiewe K. Maas L. Johannsen K. Henning und L. Sommer 《Fresenius' Journal of Analytical Chemistry》1968,242(1):17-30
Ohne Zusammenfassung 相似文献
36.
The catalytic mechanisms of transition-metal compounds during the hydrogen sorption reaction of magnesium-based hydrides were investigated through relevant experiments. Catalytic activity was found to be influenced by four distinct physico-thermodynamic properties of the transition-metal compound: a high number of structural defects, a low stability of the compound, which however has to be high enough to avoid complete reduction of the transition metal under operating conditions, a high valence state of the transition-metal ion within the compound, and a high affinity of the transition-metal ion to hydrogen. On the basis of these results, further optimization of the selection of catalysts for improving sorption properties of magnesium-based hydrides is possible. In addition, utilization of transition-metal compounds as catalysts for other hydrogen storage materials is considered. 相似文献
37.
Friedrichs O Sanchez-López JC López-Cartes C Klassen T Bormann R Fernandez A 《The journal of physical chemistry. B》2006,110(15):7845-7850
In the present work we investigate the hydrogen sorption mechanism in a MgH(2)/Nb(2)O(5) composite and analyze why Nb(2)O(5) could strongly improve hydrogen sorption kinetics in magnesium. Hereby we make use of the fact that Nb(2)O(5) nanoparticles are able to reduce the milling time significantly with the achievement of excellent sorption kinetics, and can so exclude effects occurring at long-term milling that make difficult the study of the mechanism. On the basis of extensive chemical, crystalline, and microstructural characterization of the MgH(2)/Nb(2)O(5) nanopowder system, a "pathway model" is proposed, which explains the kinetic hydrogen sorption improvement by a formation of pathways of niobium oxide species with lower oxidation state that facilitate the hydrogen transport into the sample. This mechanism is shown to be supported by additional oxidation experiments, which indicate increased oxygen diffusion through these pathways. 相似文献
38.
Nonlinear photoelectron emission from metallic nanotips is explored in the strong-field regime. The passage between the multiphoton and the optical field emission regimes is clearly identified. The experimental observations are in agreement with a quantum mechanical strong-field model. 相似文献
39.
Krasnov I Diddens I Hauptmann N Helms G Ogurreck M Seydel T Funari SS Müller M 《Physical review letters》2008,100(4):048104
Using an in situ combination of tensile tests and x-ray diffraction, we have determined the mechanical properties of both the crystalline and the disordered phase of the biological nanocomposite silk by adapting a model from linear viscoelastic theory to the semicrystalline morphology of silk. We observe a strong interplay between morphology and mechanical properties. Silk's high extensibility results principally from the disordered phase; however, the crystals are also elastically deformed. 相似文献
40.
Yeny A. Tobon Denis Bormann Aurlien Canizares Nicole Raimboux Patrick Simon 《Journal of Raman spectroscopy : JRS》2011,42(5):1109-1113
A time‐resolved intensified charge coupled device‐based Raman microspectrometer system dedicated to the study of solid samples is described, offering good optical, temporal and spatial resolution. The advantages of this approach are demonstrated on Al2O3:Cr3+, obtaining for the first time the temporal evolution of the excited state transition Ē → 2Ā. Moreover, the time dependence of the luminescence due to the chromium ion was also determined by the same Raman device. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献