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41.
In this paper, we consider Schur rings on a finite group G of ordern(n-1) suchthat G has a partition with . Then Gis characterized as follows. (a) G has subgroups E andH of order n andn-1 respectively, and , or(b)G has subgroupsK andH( K) of order 2(n-1) and n-1 respectively,and . In addition assume that G has a subsetR of sizen-1 satisfying in the groupalgebraC[G]. Then G is characterized as a collineation groupof a projective plane of order n such that G has five orbits ofpoints of lengthsn(n-1), n, n-1, 1 and 1. In particular, we characterize projective planesof ordern admitting a quasiregular collineation group of order n(n-1)as the case that E and H are normal subgroups ofG.  相似文献   
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The adsorption and decomposition of ammonia on a clean and c(2 × 2)-N ordered W(100) surface has been studied by photoemission spectroscopy (XPS and UPS). At 120 K molecularly adsorbed ammonia was identified by N(1s) core level emission at 400.9 eV and the valence emissions at 7.6 and 11.7 eV. By heating the sample stepwise the N(1s) core level shifted to lower binding energy. In the valence region, the corresponding spectral changes were obtained, where the dependence of the peak intensity on photon energy was observed. These observations were interpreted to demonstrate that adsorbed ammonia dissociates its hydrogen successively to form NHx(a) and finally to atomic nitrogen. On the other hand, ammonia was molecularly adsorbed on a c(2 × 2)-N ordered surface even at temperatures as high as 300 K, although the spectra at 400 K or above were very similar to those under a steady state flow condition, where the tungsten surface was mostly covered by atomic nitrogen. At higher ammonia pressure up to about 100 Pa thicker nitride layers were formed at 700 K, which were characterized by the N(1s) core level at 397.3 eV and a broad emission around 6 eV in the valence level.  相似文献   
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Asymptotic properties of the “attractive” vibronic coupling in a one-dimensional polymer are analyzed. The strength of the vibronic coupling grows linearly with the size of polymer, which may relate to the softening mechanism of Coulombic repulsive interaction between a Cooper pair of superconducting electrons.  相似文献   
46.
Two types of reaction mechanism were found to proceed in the photocatalytic reaction between various alcohols and water over Pt/TiO2: the reaction of physisorbed alcohol with a hole and with the ?O11 produced by the hole from H2O. The selectivity of these reactions depends strongly on the electron donor level of the absorbed alcohol species compared with that of H2O.  相似文献   
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X-ray photoelectron (XPS) and ultraviolet photoelectron (UPS) spectroscopic techniques have been employed to study the chemisorption of various molecules over metal-phthalocyanines (MePc). It was revealed that pyridine is adsorbed on the Fe atom in FePc which is accompanied by a change in the spin state without transfer of net electron charge, while HCOOH is heterolytically dissociated, the formate ion staying on the central metal atom and the proton on the bridge N atom of the porphyrin ring. H2O on MgPc behaved like HCOOH, with a proton being adsorbed at a bridge N atom. On the basis of these results, the catalytic decomposition of HCOOH and adsorption of pyridine on MePc are discussed.  相似文献   
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An interesting new type of spin-specific vibronic coupling is found. The non-adiabatic coupling induces an effective attractive interaction which softens the orginal repulsive interaction between a pair of electrons. The relation with the Cooper pair of superconducting electrons is discussed.  相似文献   
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A recent paper by Lui et al. [Z. Liu, X. Zhang, Y. Zhang, J. Jiang, Spectrochim. Acta A 67 (2007) 1232] reported on the theoretical investigations of the fully optimized geometries and electronic structures of iron (II) phthalocyanine (FePc) with the singlet spin state carried out with the restricted density functional theory (DFT) method, where the B3LYP functional was adopted for the exchange-correlation term; however, the triplet spin state was experimentally reported, and we also obtained the triplet spin state by the unrestricted DFT calculations.  相似文献   
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