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The valence-band electronic structure of a decagonal Ni-rich Al-Co-Ni quasicrystal, Al72Co8Ni20, was investigated using soft X-ray photoelectron spectroscopy. In particular, the energy distributions of the transition metal 3d bands were determined from the Co and Ni 2p-3d resonance photoemission and compared with those calculated by the discrete variational Xα method for a model cluster based on a proposed Ni-rich Al-Co-Ni approximant, as well as the 3d band observed in the Co-rich Al-Co-Ni quasicrystal, Al72Co16Ni12. In the Ni-rich Al-Co-Ni, the transition metal 3d band exhibits a peak at a binding energy, EB, of 2.3 eV, which is higher than that of the Co-rich Al-Co-Ni. The observed Ni 3d band has a single-peaked distribution around EB ∼ 2.4 eV, in contrast to the calculated bimodal and wide-spread distribution for the proposed Ni-rich Al-Co-Ni model cluster, whereas the Co 3d band is located at EB ∼ 1.7 eV, consistent with the model calculation. [ABSTRACT FROM AUTHOR]

First-principles FLAPW (full-potential linearized augmented plane wave) band calculations were performed, using the WIEN2k program package, for three isostructural gamma-brasses, Ag5Zn8, Ag9In4 and Mn3In. The FsBz (Fermi surface-Brillouin zone) interactions were successfully extracted from the case.output1 file generated from WIEN2k. This has opened a way for any users to perform FLAPW-Fourier analyses using the commercially available WIEN2k package. From the FLAPW-Fourier spectrum, it was found that the square of the reciprocal lattice vector, [image omitted] = 18, for the set of {411} and {330} lattice planes is responsible for opening a pseudogap in Ag5Zn8 and Ag9In4 gamma-brasses through FsBz interactions. In the case of Mn3In, the importance of the d-states mediated FsBz interaction involving [image omitted] = 18 is emphasized. [ABSTRACT FROM AUTHOR]

Hybrid density functional theory (HDFT) and post Hartree–Fock CCSD(T) methods are applied to elucidate the binding energies and the optimized M—O distances of transition metal oxides: MO (M = Cr, Mn, Fe, Co, Ni, Cu). The HDFT method can reproduce the CCSD(T) results, in agreement with the experimental ones. The nature of the manganese–oxygen bonds in the Mn(VI)—O, Mn(IV)—O porphyrin (PP), and Mn(V)—O PP systems are examined in relation to possible mechanisms of oxygen evolution from H2O2 and H2O in native and non‐native manganese complexes. It is found that the radical character of the high‐valent (PP)Mn(V)—O bond is remarkable, showing the strong potential to generate molecular oxygen because of its high reactivity. The electronic structure and magnetic property of μ‐oxo‐bridged manganese porphyrin dimer (PPMn(III)OMn(III)PP) are investigated for further discussion of structure and reactivity of PPMn(X)O (X = II–IV). The potential curve for release of molecular oxygen from PPMn(II)O2 is also examined to show weak affinity of O2 in the Mn complex where the oxidation number (X) of Mn is low. Implications of the computational results are also discussed in relation to oxygen evolution reactions. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 [ABSTRACT FROM AUTHOR]

A bacterium with high poly-γ-glutamate (PGA) productivity was isolated from the traditional Korean seasoning, Chung-Kook-Jang. This bacterium could be classified as a Bacillus subtilis, but sporulation in culture was infrequent in the absence of Mn2+. It was judged to be a variety of B. subtilis and designated B. subtilis (chungkookjang). L-Glutamate significantly induced PGA production, and highly elongated PGAs were synthesized. The volumetric yield reached 13.5 mg ml–1 in the presence of 2% L-glutamate. The D-glutamate content was over 50% in every PGA produced under the conditions used. During PGA production, glutamate racemase activity was found in the cells, suggesting that the enzyme is involved in the D-glutamate supply. Molecular sizes of PGAs were changed by the salt concentration in the medium; PGAs with comparatively low molecular masses were produced in culture media containing high concentrations of NaCl. B. subtilis (chungkookjang) harbors no plasmid and is the first B. subtilis strain reported with both naturally high PGA productivity and high genetic competence. [ABSTRACT FROM AUTHOR]

A new VUV beamline at the Photon Factory ring that is designed to accept radiation emitted from an undulator is described. The characteristics of the undulator and all parts of the beamline; a front end, a mirror system, and two monochromators, are described in detail. The characteristics of optical elements in the beamline are also shown. [ABSTRACT FROM AUTHOR]