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91.
Hideaki Hagihara Kenji Tsuchihara Kazuhiko Takeuchi Masahide Murata Hiroyuki Ozaki Takeshi Shiono 《Journal of polymer science. Part A, Polymer chemistry》2004,42(1):52-58
Copolymerization of olefins (ethylene and propylene) and 5‐hexen‐1‐ol pretreated with alkylaluminum was performed using [dimethysilylbis(9‐fluorenyl)]zirconium dichloride/methylaluminoxane as the catalyst. The copolymerization required extra addition of alkylaluminum to prevent deactivation of the catalyst when 5‐hexen‐1‐ol was pretreated with trimethylaluminum, whereas the triisobutylaluminum‐treated system did not require any addition of alkylaluminum. The molecular weight of the copolymer depended on the kind of alkylaluminum compound (masking reagent, additive, and cocatalyst). 13C NMR analysis proved that poly(ethylene‐co‐5‐hexen‐1‐ol) containing 50 mol % of 5‐hexen‐1‐ol acted as an alternating copolymer, whereas the poly(propylene‐co‐5‐hexen‐1‐ol) acted as a random copolymer. The surface property of the copolymers was simply evaluated by means of water drop contact angle measurement. It was found that the copolymers containing large amounts of 5‐hexen‐1‐ol units showed good hydrophilic properties. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 52–58, 2004 相似文献
92.
Takako Yamaguchi Kohei Hasegawa Shinichiro Kamino Kanako Miyachi Hiroshi Tominaga Yoshikazu Fujita 《Analytical sciences》2007,23(2):223-226
A simple and highly sensitive spectrophotometric method for the determination of uric acid (UA) was established based on fading of the o-hydroxyhydroquinonephthalein-palladium(II)-hexadecyltrimethylammonium complex. In the determination of UA, Beer's law is obeyed in the range of 0.01-0.20 microg ml(-1), with an effective molar absorptivity at 635 nm, the relative standard deviation being 6.5 x 10(5) dm(3) mol(-1) cm(-1) and 1.5% (n = 5). This method is about 20-times more sensitive than the conventional methods. The method was successfully applied to the assay of UA in human urine. 相似文献
93.
Tominaga M Suzuki K Murase T Fujita M 《Journal of the American Chemical Society》2005,127(34):11950-11951
A ca. 5 nm-sized, roughly spherical hollow complex was assembled from 12 Pd2+ ions and 24 bis(4-pyridylethenyl)-substituted bent ligands. By putting a functional group at the curvature of the ligand, the 24 functional groups were precisely arrayed inward within the spherical complex. When oligo(ethylene oxide) was anchored, the void of the hollow complex was tightly filled with a pseudo poly(ethylene oxide) nanoparticle, which showed metal ion (La3+) absorption property. 相似文献
94.
Yoshiaki Yasuno Shuichi Makita Takashi Endo Gouki Aoki Masahide Itoh Toyohiko Yatagai 《Optical and Quantum Electronics》2005,37(13-15):1157-1163
High speed complex full-range Fourier domain optical coherence tomography (FD-OCT) is demonstrated. This FD-OCT requires only a single A-scan for each single transversal position for full-range Fourier domain optical coherence tomography. The Fourier transform method is applied along the direction of the B-scan to reconstruct complex spectra, and the complex spectra compose a full-range OCT image. 相似文献
95.
Masahide Ohno 《Journal of Electron Spectroscopy and Related Phenomena》2003,130(1-3):7-17
The first theoretical study of the effect of the final-state interaction on the initial core–hole lifetime is presented. The 4s-hole lifetime width of Sn metal is calculated by an ab-initio atomic many-body theory (Green’s function method). When the final-state interaction in the 4p4d two-hole state, created by the 4s−1−4p−14d−1 f super Coster–Kronig (CK) transition of the initial 4s hole, is explicitly taken into account, the ab-initio atomic many-body calculation of the 4s-hole X-ray photoelectron spectroscopy (XPS) spectrum of Sn atom can provide excellent agreement with experiment in both the 4s-hole energy and the 4s-hole lifetime width. Otherwise, the many-body calculation underestimates considerably the 4s-hole lifetime width. The 4p4d two-hole state interacts strongly with the 4d triple-hole state by the 4p−14d−1−4d−3 f super CK transition. The interaction affects greatly the initial 4s-hole lifetime width. 相似文献
96.
97.
Plinio Innocenzi Tongjit Kidchob Luca Malfatti Stefano Costacurta Masahide Takahashi Massimo Piccinini Augusto Marcelli 《Journal of Sol-Gel Science and Technology》2008,48(1-2):253-259
Sol–gel processing of thin films involves time dependent phenomena which are basically driven by solvent evaporation. An example is evaporation induced self-assembly that is used to prepare mesoporous ordered films through self-organization of templating micelles. The possibility to follow in situ as a function of time the evolution of the system can give a better knowledge of the process and the physics and chemistry beneath. Time-resolved infrared techniques have been applied to different sol–gel systems to study time-dependent phenomena, in particular rapid scan time resolved infrared spectroscopy has been used to monitor in situ the process and as a tool to design the sol–gel synthesis. 相似文献
98.
An electrically addressable spatial light modulator is designed using nonlinear organic materials for optical information processing and display. One candidates for spatial light modulator (SLM) material is a nonlinear organic polymer of poly-methyl-methacrylate doped with disperse red 1. The measured electrooptic coefficient r33 is 2.9 pm/V at the wavelength of 633 nm. Resonator structure for a material is discussed with the goal of increasing electrooptic effects for SLM applications. 相似文献
99.
S. Yamauchi Y. Minai T. Watanabe T. Tominaga 《Journal of Radioanalytical and Nuclear Chemistry》1985,96(5):513-519
The151Eu Mössbauer spectra were measured of surface-oxidized europium/II/ sulfate with the γ-ray transmission- and conversion electron technique. The comparison of such spectra demonstrated that the change in the oxidation state of trace amounts of europium induced by surface reactions could be characterized by the conversion electron Mössbauer technique. The photochemical reduction of europium/III/ oxalate to a Eu/II/species after irradiation with a low-pressure mercury lamp was demonstrated by means of this technique as well as ESR. 相似文献
100.