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131.
Mochida T Takazawa K Matsui H Takahashi M Takeda M Sato M Nishio Y Kajita K Mori H 《Inorganic chemistry》2005,44(23):8628-8641
Charge-transfer salts of branched-alkyl biferrocenes, (1',1' '-R2-1,1' '-biferrocene)[Ni(mnt)2] (1a, R = isopropyl; 2a, R = dineopentyl) and (1',1' '-R2-1,1' '-biferrocene)2[Co(mnt)2]2 (1b, R = isopropyl; 2b, R = dineopentyl), were prepared. Their valence states were investigated using X-ray crystallography and M?ssbauer spectroscopy. Complexes 1a and 1b show segregated-stack crystal structures that contain columns of acceptors, whereas structures of 2a and 2b, which contain bulky donors, are rather discrete. All of the complexes contain mixed-valent biferrocenium monocations. A two-step valence transition was found in complex 1a. The crystal contains two crystallographically independent cations: one undergoes valence localization below room temperature; the other undergoes valence localization below ca. 130 K. The former transition is derived from asymmetry of the crystal environment around the cation, whereas the latter one is caused by symmetry lowering coupled with a spin-Peierls transition (T(C) = 133.2 K) associated with the dimerization of the acceptors. This compound was found to exhibit a dielectric response based on valence tautomerization. Other complexes (1b, 2a, and 2b) show a valence-trapped state. In all complexes, charge localization was found to occur through local electrostatic interactions between the donor's cationic moiety and the acceptor's electronegative moieties. 相似文献
132.
Christian?KanzowEmail author Christian?Nagel Hirokazu?Kato Masao?Fukushima 《Computational Optimization and Applications》2005,31(3):251-273
We present a successive linearization method with a trust region-type globalization for the solution of nonlinear semidefinite programs. At each iteration, the method solves a quadratic semidefinite program, which can be converted to a linear semidefinite program with a second order cone constraint. A subproblem of this kind can be solved quite efficiently by using some recent software for semidefinite and second-order cone programs. The method is shown to be globally convergent under certain assumptions. Numerical results on some nonlinear semidefinite programs including optimization problems with bilinear matrix inequalities are reported to illustrate the behaviour of the proposed method.The research of the fourth author was supported in part by a Grant-in-Aid for Scientific Research from Japan Society for the Promotion of Science. The research of the second author was supported by the DFG (Deutsche Forschungsgemeinschaft). 相似文献
133.
Hiroshi Fukushima 《Proceedings of the American Mathematical Society》2005,133(3):671-675
In this paper, we shall give examples of -groups that have Hall subgroups that are not -groups.
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136.
Elastic measurements have been made as a function of temperature and composition on a series of Fe-based substitutional solid solutions containing Mn, Ni and Cr. These data have been used to calculate the degree of error involved in applying statistical models to ternary carbon or nitrogen austenites when such models ignore the dilation of the substitutional lattice as a function of its composition.The results show that the error in the partial thermodynamic quantities and in the isothermal variation of the activity of the interstitial species with composition is of the order of scatter found in experimental thermodynamic data measured at constant pressure. 相似文献
137.
Kichinosuke Hirokawa Michiko Namiki 《Spectrochimica Acta Part B: Atomic Spectroscopy》1982,37(2):165-170
Coherent forward scattering spectrometry has capabilities of simultaneous multielement analysis and simple instrumentation. Considering these features the authors used a xenon lamp as a continuous excitation light source and a tellurous oxide acousto-optic tunable filter as a scanning monochromator. This simple system was applied to the simultaneous determination of manganese and chromium. An analytical procedure for the determination of manganese in steels was developed and applied to standard reference materials. It was further shown that the dynamic range for both elements can be apparently extended by the use of various exciting lines and combinations of hollow cathode lamps, the xenon lamp, the tunable filter and a spectrometer. 相似文献
138.
Seiji Fukushima Eiichi Sano Yasuro Yamane Kouichi Genda Tsuneo Matsumura 《Fiber and Integrated Optics》1998,17(4):243-253
Serial optical interconnection is proposed for connections in a Torus asynchronous transfer mode switch. A cross-point switch was developed that operates at a bit rate of 20 Gbit/s. The switching operation was successfully performed using cascaded cross-point switches through an optical interconnection configuration consisting of commercial optoelectronics devices. The measured switching rate was 10 Gbit/s, and it was limited by the responses of the optoelectronics devices. 相似文献
139.
Slavomír Nem?ák Tomá? Skála Michiko Yoshitake Nataliya Tsud Kevin C. Prince Vladimír Matolín 《Surface science》2010,604(23-24):2073-2077
Thin epitaxial alumina layers were grown on the Cu(111) surface using simultaneous aluminum deposition and oxygen exposure. Different substrate temperatures during the deposition resulted in layers with different thicknesses, growth rates, crystallinity and epitaxy. Low energy electron diffraction measurements confirmed the epitaxial growth for substrate temperatures above 870 K. The Al 2p doublet was studied by means of photoelectron spectroscopy in order to determine the alumina termination at the metal-oxide interface. A strong dependence on the preparation temperature was found and both aluminum and oxygen terminated interfaces were created. 相似文献
140.
Michiko Yoshitake Slavomír Nem?ák Tomá? Skála Nataliya Tsud Taeyoung Kim Vladimír Matolín Kevin C. Prince 《Surface science》2010,604(23-24):2150-2156
Thin epitaxial alumina films were grown on Cu(111), Cu–9 at.%Al(111), Ni(111) and NiAl(110) single crystals. The alumina films grew in such a manner that hexagonal or pseudo-hexagonal oxygen lattices were parallel to the surface of the substrates. Photoelectron spectra were obtained either with synchrotron or Al K-alpha radiation. We measured Al 2p spectra and determined the atomic species that terminated the interface between the alumina films and the substrates. The influence of Al in the substrates on the species that terminated the interface has been discussed based on thermodynamics. From valence band spectra, p-type Schottky barrier height (energy difference between the Fermi level of the metallic substrates and the valence band maximum of the alumina films, band offset) was determined. Differences in interface terminating species resulted in variations in p-type Schottky barrier height, or band alignment. 相似文献