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61.
Toshihiko Sakurai Maki Horikawa Makoto Takafuji Atsushi Kubo Hirotaka Ihara 《Applied Surface Science》2006,253(2):869-873
An l-glutamic acid-derived lipid with a terminal thiol has been synthesized and its corresponding self-assembled structure on Au(1 1 1) surfaces described. The surface morphology of the lipid self-assembled monolayer (SAM) exhibits nano-order patterning, where the height of the monolayer (approximately 1.5 nm) could be interpreted as due to the monolayer structure estimated from molecular models. The molecular orientation in the monolayer is almost perpendicular to the Au(1 1 1) surface depending on the three-point hydrogen-bonding sites in the molecule. 相似文献
62.
Tamotsu Hashimoto Yusuke Makino Michio Urushisaki Toshikazu Sakaguchi 《Journal of polymer science. Part A, Polymer chemistry》2008,46(5):1629-1637
Living cationic polymerization of 2‐adamantyl vinyl ether (2‐vinyloxytricyclo[3.3.1.1]3,7decane; 2‐AdVE) was achieved with the CH3CH(OiBu)OCOCH3/ethylaluminum sesquichloride/ethyl acetate [CH3CH(OiBu)OCOCH3/Et1.5AlCl1.5/CH3COOEt] initiating system in toluene at 0 °C. The number‐average molecular weights (Mn's) of the obtained poly(2‐AdVE)s increased in direct proportion to monomer conversion and produced the polymers with narrow molecular weight distributions (MWDs) (Mw/Mn = ~1.1). When a second monomer feed was added to the almost polymerized reaction mixture, the added monomer was completely consumed and the Mn's of the polymers showed a direct increase against conversion of the added monomer. Block and statistical copolymerization of 2‐AdVE with n‐butyl vinyl ether (CH2?CH? O? CH2 CH2CH2CH3; NBVE) were possible via living process based on the same initiating system to give the corresponding copolymers with narrow MWDs. Grass transition temperature (Tg) and thermal decomposition temperature (Td) of the poly(2‐AdVE) (e.g., Mn = 22,000, Mw/Mn = 1.17) were 178 and 323 °C, respectively. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1629–1637, 2008 相似文献
63.
Polymer electrolytes plasticized with hyperbranched polymer for lithium polymer batteries 总被引:1,自引:0,他引:1
Hyperbranched polymers (HBPs) with different terminal groups and different ethylene oxide (EO) chain lengths were prepared,
and the influence of the HBP structures including molecular weights and molecular weight distribution on the ionic conductivity
and the mechanical property of the composite polymer electrolytes composed of poly (ethylene oxide) (PEO), HBP, BaTiO3 as a ceramic filler, and LiN(CF3SO2)2 as a lithium salt were investigated. It was found that the molecular weights of the HBP do not affect significantly the ionic
conductivity, but the molecular weight distribution might affect it, and also further branching at the terminals of the HBP
led to a decrease in the ionic conductivity. The HBP with longer EO chain length was effective for enhancement of the ionic
conductivity in comparison with the HBP with shorter one. The increase in cross-linkable groups (acryloyl group) at the terminals
of the HBP improved the tensile strength, but caused the ionic conductivity to decrease. Loosely cross-linked composite polymer
electrolyte showed higher ionic conductivity and higher tensile strength than no cross-linked one.
Paper presented at the Patras Conference on Solid State Ionics — Transport Properties, Patras, Greece, Sept. 14 – 18, 2004. 相似文献
64.
Masahiro Kubo 《Journal of Mathematical Analysis and Applications》2005,307(1):232-244
We study Neumann problem for a class of nonlinear degenerate parabolic PDE. A typical nonlinearity we have in mind is, for instance, β(u)=−1/u(u>0). We establish a necessary and sufficient condition on given data for existence of solution. 相似文献
65.
Five types of non-symmetric calamitic dimers were synthesized to investigate the effect of the core structure and length of the spacer on mesomorphic properties. Two non-symmetric dimers containing a troponoid and benzenoid unit showed smectic A and C phases whereas the corresponding benzenoid dimers showed no mesophase. Non-symmetric dimers with a three-ring system showed smectic A and C phases with higher transition temperatures than the two-ring system. We propose packing models for these non-symmetric dimers by considering the direction of the dipole moments of the ring structures and microsegregation between the polar units and the non-polar chains. 相似文献
66.
Ken Hosoya Hiroshi Aoki Takuya Kubo Masashi Teramachi Nobuo Tanaka Jun Haginaka 《Journal of polymer science. Part A, Polymer chemistry》2005,43(12):2556-2566
Highly crosslinked polymer networks were characterized in terms of structural differences based on the crosslinked network structures with their chromatographic molecular retentivity for some polyaromatic hydrocarbons (PAHs). Because PAHs and some sterically bulky solutes were used in the chromatographic characterization, tiny differences in the crosslinked polymer networks were observed in terms of the chromatographic molecular retentivity. Ethylene dimethacrylate afforded molecular retentivity for anthracene, and this recognition ability changed with the polymerization time. In addition, 1,4‐butanediol dimethacrylate afforded molecular retentivity for pyrene, and this retentivity was larger than that for anthracene. The polymerization methods also affected the resulting polymer networks drastically. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2556–2566, 2005 相似文献
67.
p-Phenylenediamine bearing terminal bipyridyl moieties was synthesized by palladium-catalyzed amination. The corresponding ruthenium(II) complex was formed and characterized, providing a redox-switchable photoinduced electron-transfer system. 相似文献
68.
Ryoko Chiba Ayako Ogasawara Teppei Kubo Hiroyuki Yamazaki Masuo Umino Yoichi Ishizuka 《Analytical sciences》2003,19(5):785-789
A column-switching high-performance liquid chromatographic method with fluorescence detection was developed for the simultaneous determination of four benzamide-type anti-psychotic drugs: sulpiride, tiapride, sultopride and metoclopramide in human serum. In this method, a TSKgel Super-ODS column was used as an analytical column, and a TSKgel G 2000SW was prepared as a pretreatment column. Under the optimized analytical conditions, four benzamide-type anti-psychotic drugs were eluted within 18 min. The detection limits (S/N = 3) for sulpiride, tiapride, sultopride and metoclopramide are 1 ng/ml, 4 ng/ml, 2 ng/ml and 0.5 ng/ml, respectively. Finally, the method was applied to the determination of sulpiride in human serum samples obtained after a single oral dose of sulpiride. 相似文献
69.
70.
Kazuhiro Kubo 《Journal of Molecular Spectroscopy》2003,222(2):255-262
Rotational spectra of four rare isotopic species of OCS were observed in the 110-690 GHz region with a source-modulated submillimeter-wave spectrometer. Spectral lines of 18O13CS, O13C36S, 18OC36S, and 18O13C34S were measured in their natural abundances, 21.4, 1.51, 0.29, and 0.95 ppm, respectively. The rotational constants and centrifugal distortion constants were precisely determined from observed line frequencies by least squares methods. In order to facilitate sensitivity examination in the submillimeter-wave region, transition frequencies and peak absorption coefficients were calculated and tabulated for the spectral lines of the four species up to the 1000 GHz region. 相似文献