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171.
Hiroaki Nitani Masato Yuya Takahiro Ono Takashi Nakagawa Satoshi Seino Kenji Okitsu Yoshiteru Mizukoshi Shuichi Emura Takao A. Yamamoto 《Journal of nanoparticle research》2006,8(6):951-958
A sample of Au–Pd bimetallic nanoparticles supported on γ-Fe2O3 was synthesized in a sonochemically one-pot process. The structural analyses of the synthesized sample were performed by the techniques of X-ray Absorption Fine Structure (XAFS), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and UV–vis spectrometry. Results indicated that the synthesized sample formed a core-shell structure in which a gold core was surrounded by a thin palladium shell. The reaction rate constant for the hydrogenation of cyclohexene of the present sample showed higher value than that of Pd nanoparticles supported on γ-Fe2O3 and core-shell structured Au–Pd nanoparticles supported on SiO2. The present sample is a promising catalyst material which has a high catalytic activity. 相似文献
172.
Takao Esaka 《Ionics》2004,10(5-6):358-365
The principle and availability of Neutron Radiography are demonstrated. The technique is actually applied to obtain the images
as to lithium in the oxide lithium ion conductors and/or hydrogen in the hydrogen storage alloys. From analysis of the lithium
or hydrogen distribution, the ionic transport number and the diffusion coefficient can be calculated and the hydrogenation
process is discussed. In the case imaging the special cross-section in the sample, Neutron Computed Tomography is more favorable.
Here, it will be demonstrated using our actual experimental results that the NCT technique is also useful in the field of
Solid State Ionics to clarify the ion distribution and movement.
Paper presented at the Patras Conference on Solid State Ionics, Patras, Greece, Sept. 14–18, 2004. 相似文献
173.
Eiji Ihara Takao Wake Naoki Mokume Tomomichi Itoh Kenzo Inoue 《Journal of polymer science. Part A, Polymer chemistry》2006,44(19):5661-5671
α,α‐Dibromotoluene 1 was found to be polymerized by the reaction with excess Mg to give poly(phenylmethylene)s 2 , whose main chains were partially dehydrogenated to carbon–carbon double bonds (C?C). The C?Cs in 2 can be brominated by treatment with Br2. The polymerization mechanism was presumed to include the formation of Grignard reagents of various species with benzylic C? Br bonds and the nucleophilic attacks of the Grignard reagents to various compounds with benzylic C? Br bonds. Copolymerization of 1 with dichlorodimethylsilane successfully proceeded. Mg/Cu‐mediated copolycondensation of 1 with 1,6‐dibromohexane proceeded to give polymers that have similar compositions to those of random copolymers of ethylene and styrene. © 2006Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5661–5671, 2006 相似文献
174.
Here we summarize multi-terabit long-haul transmission experiment and distributed Raman amplification (DRA) technologies. As well, we investigate the configuration of dispersion-managed fibers for the DRA-based system from the viewpoint of the fiber non-linear effect and required pumping power. 相似文献
175.
Masashi Nakagawa Tatsuo Iwasa Satoshi Kikkawa Toshifumi Takao Yasutsugu Shimonishi Motoyuki Tsuda 《Photochemistry and photobiology》1997,65(1):187-191
Abstract— We determined the structure and site of fatty acid incorporated in octopus rhodopsin using a combination of fluorescence label and enzymatic cleavage methods in conjunction with fast-atom bombardment (FAB) mass spectrometry. A single peptide containing two adjacent cysteines, Cys337 and Cys338, was successfully isolated using the fluorescence from a dye conjugated to Cys345. The FAB mass spectrometric analysis of the peptide (323phe-340 phe) revealed that two palmitoyl groups are linked to Cys337 and Cys338 via thioester bonds in octopus rhodopsin as in bovine rhodopsin. 相似文献
176.
A selective off-line preconcentration technique for the V(V) complex with 4-(2-pyridylazo)resorcinol has been developed and successfully applied to the determination of V(V) in an air-borne sample. The target complex was separated from excess reagent using an ODS cartridge and water as the eluent. The complex was then concentrated on another ODS cartridge using tetrabutylammonium bromide and eluted with methanol; the eluate was applied to a one-drop concentration/HPLC. A detection limit as low as (6.05 +/- 0.82)x 10(-11) M (5 ppt) was achieved. 相似文献
177.
Syntheses of 3-substituted indazoles and benzoisoxazoles were efficiently accomplished with the aid of Pd-catalyzed intramolecular carbon-nitrogen and carbon-oxygen bond formations. The catalyst system described herein allows the cyclization to proceed under very mild conditions and thus could be applied to a wide range of substrates with acid- or base-sensitive functional groups. A total synthesis for the indazole ring-containing natural product nigellicine is also described. 相似文献
178.
Stereoselective synthesis of tetrahydrofuro- and tetrahydropyrano[3,2-c]benzothiopyrans was achieved by intramolecular [4+2]cycloaddition of o-thiobenzoquinone methides that were generated in situ from bis(2-formylphenyl) disulfide and alkenols in the presence of iodine under mild reaction conditions. 相似文献
179.
On Kodaira energy and adjoint reduction of polarized manifolds 总被引:2,自引:0,他引:2
Takao Fujita 《manuscripta mathematica》1992,76(1):59-84
180.
Takao Tsuda 《Numerische Mathematik》1975,24(5):395-414
The difficulty is first shown in the nonlinear interpolation of functions defined in a space of very many dimensions. There is a method using a sampling technique [J. ACM, Vol. 17, pp. 420–425, July 1970] that works fairly well in the regime ofk~10?20 (k=number of dimensions). The sampling errors, however, increase exponentially with increasingk, so that fork greater than the above values the computation is no more feasible. This is due to the subtraction between two large sums of about the same magnitude, each of which suffers stochastic fluctuations accompanying the samplings. To avoid this difficulty, a “pairwise” sampling method is devised where one draws two samples at a time when required, one from each of these two sums of terms. With the use of this technique, standard errors are reduced by orders of magnitude. Some details of algorithm are given together with typical computed examples. 相似文献