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51.
Smectic layer structure of ferroelectric liquid crystal formed between fine polymer fibres 总被引:1,自引:0,他引:1
Hideo Fujikake Takashi Toyooka Takeshi Murashige Hiroto Sato Yoshiki Iino Masahiro Kawakita Hiroshi Kikuchi 《Liquid crystals》2002,29(7):881-887
This paper describes the alignment of ferroelectric liquid crystal (FLC) structures formed between aligned polymer fibres, where the FLC smectic layers are determined by polarising microscopy and X-ray diffraction. The FLC/polymer composite films were formed from a nematic phase FLC/monomer solution using a photopolymerisation-induced phase separation method. It was found that bending of the FLC smectic layers was induced in both the film plane and the cross-sectional plane at the phase transition from smectic A to chiral smectic C of the FLC material. The light transmittance properties of the composite film between crossed polarizers was analysed by light propagation simulation in several optical anisotropic media, based on the evaluated smectic layer model. 相似文献
52.
Hideo Kurosawa 《Journal of organometallic chemistry》2004,689(24):4511-4520
This review summarizes the author’s contributions to the field of chemistry of group 10 metal complexes containing unsaturated hydrocarbon ligands, with a brief introduction showing how his research subject has shifted from mononuclear type to multinuclear type complexes. New structure and reactivity trends in the multipalladium complexes with bridging allyl and allenyl/propargyl ligands, as well as bridging conjugated polyene molecules are discussed in terms of some unique bonding features of these complexes. 相似文献
53.
M. Ueshima K. Sano M. Ikeda K. Yoshino J. Okamura 《Research on Chemical Intermediates》1998,24(2):133-141
The selective catalytic oxidation (SCO) of ammonia to N2 was studied by using a series of noble metal-V2O5-WO3 catalysts supported on titania-silica (TS) prepared by coprecipitation method. In the V2O5-WO3 catalyst system, the use of TS as a support was very effective to enhance catalytic activity compared with TiO2 or SiO2 alone. The addition of a slight amount of Pd and Ir to V2O5-WO3/TS catalyst caused also remarkable enhancement of the catalytic activity without decreasing the selectivity to N2. The present catalysts provide remarkably high catalytic performance for SCO of ammonia to N2 under the practical reaction conditions for an industrial application. 相似文献
54.
55.
The oxygen ions of the β-VOPO4 catalyst were exchanged with an
tracer by a reduction–oxidation method and by a catalytic oxidation of but-1-ene using
2. The bands at 992 and 900 cm−1 were more shifted to lower frequencies than those at 1076 and 1002 cm−1. Applying the correlation between the Raman bands and stretching vibrations in the literature, the exchanged oxygen species were estimated. The results suggest that the P–O–V vacancies corresponding to 992 and 900 cm−1 were responsible for reoxidation and the V=O oxygen corresponding to the 1002 cm−1 band of β-VOPO4 was not. The (VO)2P2O7 was oxidized to β-VOPO4 by O2 above 823 K. The insertion position of oxygen was determined at the bands at 992 and 900 cm−1 of β-VOPO4 using
2, which is the same as the exchanged position. 相似文献
56.
Liao Shijie Ying Weiyong Fang Dingye Kameyama Hideo 《Reaction Kinetics and Catalysis Letters》2005,85(1):205-213
Summary Catalytic combustion of toluene, propylene and CO over Pt/Al2O3 /Al catalyst was investigated. Strong inhibition effects are observed when the mixture of toluene, propylene and CO is oxidized. A reaction mechanism of catalytic combustion over Pt/Al2O/Al is proposed. The results from kinetic models are in good agreement with the experimental data. 相似文献
57.
Masahiro Manabe Toshihiro Ochi Hideo Kawamura Hajime Katsu-ura Masaki Shiomi Mandeep Singh Bakshi 《Colloid and polymer science》2005,283(7):738-746
The partial molar volumes (Va) of 1-alkanols (carbon number, m=5, 6, 7) in - and -cyclodextrin (CD) solutions at 5.00 mmol kg–1 have been determined as a function of alkanol concentration (Ca) between 293.2 and 308.2 K by using a dilatometer. It has been observed that with an increase in Ca, Va increased in -CD solution but decreased in -CD solution, asymptotically to a value of Va in CD-free water. The dependence of Va on Ca provided the binding constant (K) of 1:1 complex, the volume change in complex formation, and the partial molar volume of complex itself. The complex formation mechanism has been discussed on the basis of these values and their carbon number dependences in the respect of geometric behavior, hydrophobic interaction, and van der Waals interaction. It is concluded that the CD cavity in water is not rigid but flexible for fitting in nicely with guest molecule. 相似文献
58.
A general method for acylation of indoles at the 3-position with acyl chlorides in the presence of dialkylaluminum chloride 总被引:1,自引:0,他引:1
[reaction--see text] Indoles are selectively acylated at the 3-position in high yields on treatment with a wide variety of acyl chlorides in CH(2)Cl(2) in the presence of diethylaluminum chloride or dimethylaluminum chloride. The reaction proceeds under mild conditions and is applicable to indoles bearing various functional groups without NH protection. 相似文献
59.
Kimura T Yoshino M Yamane T Yamato M Tobita M 《Langmuir : the ACS journal of surfaces and colloids》2004,20(14):5669-5672
A diamagnetic particle with magnetic susceptibilities chi3 < chi2 = chi1 < 0 was subjected to a rotating magnetic field to obtain an alignment of the chi3 axis (the smallest susceptibility axis) in the direction perpendicular to the plane of the rotating magnetic field. A polymer short fiber, whose fiber axis coincides with the chi3 axis, was suspended in a fluid with the same density, and then a rotating magnetic field generated by a rotation of a pair of permanent magnets was applied. The fiber axis, rotating following the applied field, finally ended up with an alignment perpendicular to the plane of the rotating magnetic field. The experimental data on the time course of the alignment was in good agreement with the numerical calculation based on the equation of rotation. 相似文献
60.
[reaction: see text] A concise and stereoselective synthesis of the chiral building block, dioxanylpiperidene 4 as a precursor for deoxyazasugars, starting from the Garner aldehyde 5 using catalytic ring-closing metathesis (RCM) for the construction of the piperidine ring is described. The asymmetric synthesis of 1-deoxygalactonojirimycin and its congeners 1-3 was carried out via the use of 4 in a highly stereocontrolled mode. 相似文献