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981.
Yasuhiro Morisaki 《Journal of organometallic chemistry》2004,689(7):1271-1276
Novel π-conjugated polymers containing (η6-arene)Cr(CO)3 in the main chain based on poly(p-phenylene-ethynylene) were prepared by the Sonogashira coupling reaction of η6-(1,4-diethynylbenzene)tricarbonylchromium with 1,4-diiodo-2,5-dialkoxybenzenes. The polymers were soluble in common organic solvents and characterized by NMR and FT-IR spectra. The polymers exhibited an absorption maximum at around 390 nm, which showed a red shift of approximately 30 nm compared to that of the model compound. Cyclic voltammogram showed a single reversible oxidation peak derived from the (η6-arene)Cr(CO)3 unit. 相似文献
982.
Tada M Shimamoto M Sasaki T Iwasawa Y 《Chemical communications (Cambridge, England)》2004,(22):2562-2563
Supported Pd-P and Pd-N complexes prepared by a selective reaction of Pd-monomer precursors with SiO2, Al2O3 and TiO2 surfaces and characterized by EXAFS, XPS, XRF and gas analysis exhibited oxide surface-promoted catalysis for the catalytic intrahydroamination of 3-amino propanol vinyl ether to produce a cyclic amine. 相似文献
983.
984.
As the first example of a planar chiral ionic liquid, a cyclophane-type imidazolium salt was synthesized; its potential use in chiral recognition was demonstrated by 1H NMR studies. 相似文献
985.
[reaction: see text] A highly efficient, facile, one-pot regioselective synthesis of a series of phenylpropanoid-substituted flavan-3-ols is described. The mechanism involves dienone-phenol rearrangement followed by a Michael-type reaction. 相似文献
986.
Hiromichi Arai Toshiya Kunisaki Yasuhiro Shimizu Tetsuro Seiyama 《Solid State Ionics》1986,20(4):241-248
The electrical conductivity of sintered specimens of (CeO2)1−x(CaO)x was investigated by employing a standard four-probe dc technique as a function of temperature between 400°C and 900°C, composition from 0.10x0.80, and oxygen partial pressure from 10−18 to 1 atm. The temperature and composition dependence of the emf have been carried out with a concentration cell. X-ray diffraction studies indicated that a cubic fluorite crystal remained in all specimens studied, although the solubility limit of CaO in CeO2 was assumed to lie close to 23 mol% from the change of the lattice constant. The magnitude of the conductivity decreased slightly with increase of the dopant concentrations up to x=0.50. The conductivity of these specimens was about 100 times larger than that of calcia-stabilized zirconia at 600°C with a smaller activation energies of 0.83–0.89 eV. With further increasing dopant concentrations, the magnitude of the conductivity was found to decrease remarkably. With an increase in the dopant concentration, the domain of primarily ionic conduction extended to a lower partial pressure. The conductivity of (CeO2)0.50(CaO)0.50 was found to be primarily ionic down to 10−12 atm even at 900°C. These results indicate that CaO-doped CeO2 may be more an attractive candidate for fuel cells and other applications. 相似文献
987.
988.
Yoshio Hamashima Sadao Yamamoto Shoichiro Uyeo Mitsuru Yoshioka Masayuki Murakami Hisao Ona Yasuhiro Nishitani Wataru Nagata 《Tetrahedron letters》1979,20(28):2595-2598
Reaction of 2β-unsubstituted or functionalized-methyl 6-epipenicillin sulfoxides with tervalent phosphorus compounds gave azetidinone-epi-oxazolines , important intermediates in synthesis of 7α-methoxy-1-oxacephems. Preparation of the 2β-functionalized-methyl substrates is described also. 相似文献
989.
We have developed a novel branched optical waveguide using a stacked directional coupler, which consists of two Si3N4 core layers (each 0.3 μm thick) stacked with a thin (0.2 μm) SiO2 film in between. Using this stacked high-index-contrast system, the size of the multiple branched waveguides can be dramatically reduced compared with the conventional Y-shaped branches. A four-branch optical waveguide is designed and fabricated, and good performance of distribution power of 25 ± 4% to each branch has been achieved. 相似文献
990.
Yasuhiro Nakagawa 《Mathematische Annalen》2003,325(1):31-53
The Bando-Calabi-Futaki character of a compact K?hler manifold is an obstruction to the existence of K?hler metrics with
constant scalar curvature, which is a generalization of the Futaki character of a Fano manifold. In this paper, we shall establish
an interpretation of the Bando-Calabi-Futaki character as a secondary characteristic class. By using this interpretation,
we shall also prove that the Bando-Calabi-Futaki character can be lifted to a group character.
Received: 26 October 2000 / Revised version: 25 October 2001 / Published online: 16 October 2002
RID="★"
ID="★" Partly supported by the Grant-in-Aid for Encouragement of Young Scientists (No. 09740047), The Ministry of Education,
Science, Sports and Culture, Japan
Mathematics Subject Classification (2000): 32Q20, 32Q15, 32M05, 57R30 相似文献