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151.
Katsuhiko Matsuzaki 《Israel Journal of Mathematics》2004,140(1):113-123
We prove that if the Bers embeddings of the Teichmüller spaces of infinitely generated Fuchsian groups are coincident, then
these Fuchsian groups are the same. 相似文献
152.
Jing Chen Masahiro Ueda Katsuhiko Asada Keiji Taniguchi 《Optics and Lasers in Engineering》1998,29(1):221
An optical method to measure the weight density of raw glass wool has been developed for use in a manufacturing plant. The method is based on the light attenuation theory. The system consists of the usual white light as a light source, a solar cell as a light-sensitive receiver, an amplifier, a personal computer with an A/D converter for data acquisition and a monitor for display of the data. The accuracy of the system was found to be above 98% and the system can be effectively applied to practical use in the factory. The system may be further applied for quality control in manufacturing raw glass wool. 相似文献
153.
Katsuhiko Ono Shoji Tanaka Yoshiro Yamashita 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1994,106(19):2030-2032
154.
Hideki Matsune Teruoki Tago Kazuhiro Shibata Katsuhiko Wakabayashi Masahiro Kishida 《Journal of nanoparticle research》2006,8(6):1083-1087
A nonionic reverse-micelle based approach is described for fabrication of a network structure consisting of chain-like arrays of gold nanoparticles, followed by coating process with a uniform silica layer using a sol-gel method. The hexadecyl-poly (ethylene oxide-15) ether (designated C16E15) is used as a template for this study. The effects of a water-to-surfactant molar ratio (w) as well as the concentration of tetraethyl orthosilicate ([TEOS]oil) are investigated on the resulting organized structures. 相似文献
155.
Kazuhiko Ishikawa Hitomi Yamano Ki-ichiro Kagawa Katsuhiko Asada Koichi Iwata Masahiro Ueda 《Optics and Lasers in Engineering》2004,41(1):19-29
An optical method for directly measuring the thickness of a thin transparent film has been proposed by means of multi-wave laser interference at many incident angles, and confirmed experimentally by means of equipment made on an experimental basis. Two methods are available: one can be used when an index of refraction of the film, a wavelength λ, and two successive angles of incidence at which the sinusoidal light intensity has minimum values, are known (Method I), and another can be used without an index of film refraction when three successive angles of incidence and a wavelength are known (Method II). The smallest measurable thickness is 1.43λ for Method I, and 2.5λ for Method II. The largest measurable thickness is about 100λ for both methods. The measurement error by means of numerical calculation is Δh/h−1.01×10−2, and that obtained experimentally with an angular resolution of incident light of 0.3° is Δh/h7×10−2 for Method I. The refractive index can also be measured by means of Method II. 相似文献
156.
Strain‐Induced Double Carbon–Carbon Bond Activations of Cycloparaphenylenes by a Platinum Complex: Application to the Synthesis of Cyclic Diketones
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Dr. Eiichi Kayahara Toshiki Hayashi Dr. Katsuhiko Takeuchi Prof. Dr. Fumiyuki Ozawa Keita Ashida Prof. Dr. Sensuke Ogoshi Prof. Dr. Shigeru Yamago 《Angewandte Chemie (International ed. in English)》2018,57(35):11418-11421
The carbon–carbon (C?C) bond activation of [n]cycloparaphenylenes ([n]CPPs) by a transition‐metal complex is herein reported. The Pt0 complex Pt(PPh3)4 regioselectively cleaves two C?C σ bonds of [5] CPP and [6]CPP to give cyclic dinuclear platinum complexes in high yields. Theoretical calculations reveal that the relief of ring strain drives the reaction. The cyclic complex was further transformed into a cyclic diketone by using a CO insertion reaction. 相似文献
157.
Yui T Tsuchino T Itoh T Ogawa M Fukushima Y Takagi K 《Langmuir : the ACS journal of surfaces and colloids》2005,21(7):2644-2646
Composite films of a meso-(tetramethylpyridinium)porphyrin (TMPyP) hybrid incorporated in mesoporous silica (MPS) and cast on a methyl viologen (MV2+)/titania nanosheet hybrid were synthesized and a light-induced charge separation between the two could be observed. These composite thin films were able to initiate a one-electron reduction of the MV2+ ions accompanied by the simultaneous decomposition of the TMPyP organic dye within the mesoporous silica channels. 相似文献
158.
Nakamura H Kamakura T Ishikura M Biellmann JF 《Journal of the American Chemical Society》2004,126(19):5958-5959
Synthesis of allenes has been achieved by using palladium-catalyzed hydrogen-transfer reactions. Various propargylic amines, which were readily prepapred from iodobenzenes and propargylic amines by Sonogashira coupling reaction, underwent the hydrogen-transfer reaction in the presence of Pd2dba3.CHCl3/(C6F5)3P catalyst at 100 degrees C in dioxane for 24 h, giving the corresponding allenes in 43-99% yields. Various propargylic alcohols containing a propargylic aminomethyl group, synthesized by the addition of lithium acetylides of N,N-diisopropylprop-2-ynylamine to aldehydes and a ketone, also underwent the hydrogen-transfer reaction in the presence of Pd2dba3.CHCl3 catalyst and (C6F5)3P at 80 degrees C in dioxane, giving the corresponding allenes in 56-92% yields. In the current transformation, propargylic amines can be handled as an allenyl anion equivalent and introduced into various electrophiles to be transformed into allenes under palladium-catalyzed conditions. 相似文献
159.
The palladium-catalyzed allene transformation reaction from propargylic amines proceeded in the presence of Pd2(dba)3·CHCl3 (5 mol %) and (C6F5)2PC2H4P(C6F5)2 (10 mol %) in CHCl3 at room temperature to give the corresponding allenes in good to high yields. Dicyclohexyl groups substituted on the nitrogen of propargylic amines were found to be effective for the current transformation and the conjugated ene-allenes 4 were synthesized from the corresponding propargylic amines 3 under mild conditions. 相似文献
160.
Ariga K Urakawa T Michiue A Kikuchi J 《Langmuir : the ACS journal of surfaces and colloids》2004,20(16):6762-6769
As a novel category of two-dimensional lipid clusters, dendrimers having an amphiphilic structure in every unit were synthesized and labeled "spider-web amphiphiles". Amphiphilic units based on a Lys-Lys-Glu tripeptide with hydrophobic tails at the C-terminal and a polar head at the N-terminal are dendrically connected through stepwise peptide coupling. This structural design allowed us to separately introduce the polar head and hydrophobic tails. Accordingly, we demonstrated the synthesis of the spider-web amphiphile series in three combinations: acetyl head/C16 chain, acetyl head/C18 chain, and ammonium head/C16 chain. All the spider-web amphiphiles were synthesized in satisfactory yields, and characterized by 1H NMR, MALDI-TOFMS, GPC, and elemental analyses. Surface pressure (pi)-molecular area (A) isotherms showed the formation of expanded monolayers except for the C18-chain amphiphile at 10 degrees C, for which the molecular area in the condensed phase is consistent with the cross-sectional area assigned for all the alkyl chains. In all the spider-web amphiphiles, the molecular areas at a given pressure in the expanded phase increased in proportion to the number of units, indicating that alkyl chains freely fill the inner space of the dendritic core. The mixing of octadecanoic acid with the spider-web amphiphiles at the air-water interface induced condensation of the molecular area. From the molecular area analysis, the inclusion of the octadecanoic acid bears a stoichiometric characteristic; i.e., the number of captured octadecanoic acids in the spider-web amphiphile roughly agrees with the number of branching points in the spider-web amphiphile. 相似文献