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111.
112.
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
113.
Tilley RD Warner JH Yamamoto K Matsui I Fujimori H 《Chemical communications (Cambridge, England)》2005,(14):1833-1835
Silicon nanocrystals with a uniform size distribution were synthesized in inverse micelles using powerful hydride reducing agents. The silicon nanocrystals surfaces were then stabilized with 1-heptene to produce particles with strong blue photoluminescence. 相似文献
114.
115.
Hisayuki Matsui Masayoshi Tamaki Shoichi Nasu Toshimasa Kurasawa 《Journal of Physics and Chemistry of Solids》1980,41(4):351-355
Electrical resistivities of arc-melted uranium carbides, UC, UC2, U2C3 and UC + UC2, were measured over the temperature range between 4 and 1900 K. The monocarbide, dicarbide and the mixture of carbides showed metallic character in their resistivity dependence on temperature above 30 K, while below this the resistivities were constant. U2C3 showed a knee in the resistivity curve at 54.0 K corresponding to a magnetic transition. Above 1100 K, the resistivity of U2C3 did not vary with temperature. The resistivity of the mixture (UC + UC2 with U2C3 precipitates) showed an arrest between 800 and 950 K. 相似文献
116.
Y Sasaki M Matsui H Fujita M Hosono M Taguchi K Suzuki S Sakurada T Sato T Sakurada K Kisara 《Chemical & pharmaceutical bulletin》1985,33(4):1528-1536
117.
118.
Y. Kondo T. Nakamura Y. Satou T. Matsumoto N. Aoi N. Endo N. Fukuda T. Gomi Y. Hashimoto M. Ishihara S. Kawai M. Kitayama T. Kobayashi Y. Matsuda N. Matsui T. Motobayashi T. Nakabayashi T. Okumura H.J. Ong T.K. Onishi K. Ogata H. Otsu H. Sakurai S. Shimoura M. Shinohara T. Sugimoto S. Takeuchi M. Tamaki Y. Togano Y. Yanagisawa 《Physics letters. [Part B]》2010
119.
The temperature dependence on the segregation behavior of the ferritic stainless steel single crystal (1 1 1) surface morphology has been examined by scanning tunneling microscopy (STM), Auger electron spectroscopy (AES), and low energy electron diffraction (LEED). AES clearly showed the surface segregations of chromium and nitrogen upon annealing. Nanoscale triangular chromium nitride clusters were formed around 650 °C and were regularly aligned in a hexagonal configuration. In contrast, for the ferritic stainless steel (1 1 1) surface with low-nitrogen content, chromium and carbon were found to segregate on the surface upon annealing and Auger spectra of carbon displayed the characteristic carbide peak. For the low-nitrogen surface, LEED identified a facetted surface with (2 × 2) superstructure at 650 °C. High-resolution STM identified a chromium carbide film with segregated carbon atoms randomly located on the surface. The facetted (2 × 2) superstructure changed into a (3 × 3) superstructure with no faceting upon annealing at 750 °C. Also, segregated sulfur seems to contribute to the reconstruction or interfacial relaxation between the ferritic stainless steel (1 1 1) substrate and chromium carbide film. 相似文献
120.
This paper considers multiobjective integer programming problems where each coefficient of the objective functions is expressed by a random fuzzy variable. A new decision making model is proposed by incorporating the concept of probability maximization into a possibilistic programming model. For solving transformed deterministic problems, genetic algorithms with double strings for nonlinear integer programming problems are introduced. An interactive fuzzy satisficing method is presented for deriving a satisficing solution to a decision maker by updating the reference probability levels. An illustrative numerical example is provided to clarify the proposed method. 相似文献