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361.
Etsuo Hasegawa Jun-Ichi Nemoto Tatsuya Kanayama Eishun Tsuchida 《European Polymer Journal》1978,14(2):123-127
To synthesize polymer-covalently bonded meso-tetraphenylporphin derivatives, two porphyrin vinyl monomers, viz., 5-mono(p-acrylamidophenyl)-10,15,20-triphenylporphin and 5,10,15,20-tetra(α,α,α,α-o-methacrylamidophenyl)porphin, were prepared and characterized by elemental analyses, nuclear magnetic resonance, infrared and mass spectrometry. The porphin-bonded polymers were synthesized by radical copolymerization of the porphin monomers with styrene and other monomers and purified by gel permeation chromatography. The spectral properties of these compounds in the Q-band region are also discussed. 相似文献
362.
Katsuhiro Mizoguchi Tamotsu Kamiya Eishun Tsuchida Isao Shinohara 《Journal of polymer science. Part A, Polymer chemistry》1979,17(3):649-658
The electric properties of polymer composites with highly conductive 7,7,8,8-tetracyanoquinodimethan (TCNQ) salts such as quinolinium–TCNQ complex salt (), acridinium–TCNQ complex salt (), and N-methylacridinium–TCNQ complex salt () were studied. Polyacrylonitrile (PAN), poly(N-vinylcarbazole) (PVK), and poly(4-vinylpyridine), (P4VP), etc., were chosen as matrix polymers. The resistivity (ρ) of the was 0.37 Ω cm at the content of 20 wt % in the film. When the content of was increased up to 40 wt%, a phase separation of the needle crystals was observed and the ρ value increased. When was dispersed into PAN or PVK, the separation was also observed and the samples showed low conductivity. The uniform films were obtained in the and systems, but the values of ρ were high because of the degradation of the TCNQ salts. Uniform films with the naked eye were obtained in the and systems, and the values of Ω were 0.37, 1.05, and 3.40 Ω cm, respectively. was stable even when dispersed into P4VP. The properties of the composites were influenced by the combination of the TCNQ salts and the polymers. The uniformity and the stability of the composites were necessary to obtain the high conductive composites. 相似文献
363.
Ohne Zusammenfassung 相似文献
364.
Koji Abe Mikio Koide Eishun Tsuchida 《Journal of polymer science. Part A, Polymer chemistry》1977,15(10):2469-2477
The interactions of integral-or pendant-type polycations with sodium-1-anilino-8-naphthalene sulfonate (ANS) were studied by means of their fluorescent spectra. The emission maxima shift to the lower wavelength and fluorescent intensities increase greatly as a result of such complexations. This result may be attributed to the electrostatic interaction and the specific nonpolar environment around the bound ANS. The hydrophobic property in the domain formed by a polycation chain depends on the increase of methylene groups or the existence of a xylylene group between two adjacent cationic sites on the main chain, the existence of benzyl groups on the side chains, and the increase of their molecular weights. It is shown that the hydrophobicities in the domains of polyelectrolytes also change with their conformational changes, i.e., the more contracted their conformations are, the stronger their hydrophobicities are. 相似文献
365.
Effects of dissolved gases and an echo contrast agent on ultrasound mediated in vitro gene transfection 总被引:9,自引:0,他引:9
The effects of acoustic cavitation on in vitro transfection by ultrasound were investigated. HeLa cells were exposed to 1.0 MHz continuous ultrasound in culture media containing the luciferase gene. Transfection efficiency was elevated when an echo contrast agent, Levovist was added or air was dissolved in the medium. When cells were sonicated in medium saturated with Ar, N2 or N2O which have different gamma values (Cp/Cv), or were saturated with He, Ar or Ne with different thermal conductivities, the effectiveness for the dissolved gases in the ultrasound mediated transfection was Ar > N2 > N2O or Ar > Ne > He, respectively. When free radical formation in water by ultrasound was monitored as a measure of inertial cavitation, it was similarly affected by dissolved gases. These results indicate that the efficiency of ultrasound mediated transfection was significantly affected either by occurrence of or by modification of inertial cavitation due to various gases. 相似文献
366.
367.
Hiromi Sakai Shinji Takeoka Hiroaki Yokohama Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1992,3(7):389-394
A carbonyl hemoglobin (HbCO) solution was stirred with a mixed powder of polymerizable 1,2-bis(2,4-octadecadienoyl)-sn-glycero-3-phosphocholine (DODPC), cholesterol and stearic acid (7/7/2 by mol). The mixture was extruded through polycarbonate membrane filters (final pore size = 0.2 μm Ø). The average diameter of the resulting vesicles was 203 ± 39 nm. The [Hb]/[Lipid] ratio (the weight ratio of Hb in vesicle to lipid) increased with the Hb concentration, and decreased with the NaCl concentration. A maximum [Hb]/[lipid] ratio was observed at pH 6.9, which was the same as the isoelectric point of Hb. The vesicles were stabilized by γ-irradiation (60Co) because the bilayer lipids bound each other to yield polyphospholipids. Denaturation of Hb by γ-irradiation was not detected. These polyphospholipid vesicles encapsulating Hb were stable even against the freeze–thaw cycles and the freeze-drying procedure. 相似文献
368.
Controlling interparticle spacing among metal nanoparticles through metal-catalyzed decomposition of surrounding polymer matrix 总被引:1,自引:0,他引:1
Akamatsu K Shinkai H Ikeda S Adachi S Nawafune H Tomita S 《Journal of the American Chemical Society》2005,127(22):7980-7981
Systematic and reproducible control over average interparticle spacing of Pt, Ni, and Cu nanoparticles embedded in polyimide thin layers was achieved. The metal-catalyzed decomposition of polyimide matrixes surrounding metal nanoparticles causes a decrease in the composite layer thickness, while maintaining the size of nanoparticles. This ability provides an effective methodology for the preparation of metal/polymer nanocomposites with tailored microstructures and holds great promise toward the fundamental understanding of the physical interactions among metal nanoparticles. 相似文献
369.
Yutaka Aoyagi Taku Inariyama Yaeko Arai Sanae Tsuchida Yasuko Matuda Hiroyuki Kobayashi Akihiro Ohta
Teruo Kurihara
Sumiyo Fujihira 《Tetrahedron》1994,50(48):13575-13582Total synthesis of (±)-oxerine (1), a monoterpene alkaloid, starting from 3-bromopyridine (7) is described. The key reaction in this sequence is the samarium iodide (SmI2)-mediated intramolecular cyclization of γ-ethynyl bromide (4). 相似文献
370.
Eishun Tsuchida Kiwamu Kitamura Isao Shinohara 《Journal of polymer science. Part A, Polymer chemistry》1972,10(12):3639-3650
Equations for the degree of polymerization and the cooligomer composition in the styrene (A)–methyl methacrylate (B)–CCl4(S) system were derived from the assumed reaction scheme by the use of some assumptions for simplification, and their appropriateness was examined. The chain transfer constants of the growing radicals of styrene (CSA) and methyl methacrylate (CSB) to CCl4, which were estimated from the apparent chain transfer constants CSAB in the cooligomerization system, agreed with the homooligomerization values. This means that the degree of the polymerization of the cooligomer can be expressed by the equation: where Pn is the degree of polymerization of the cooligomer and PnO is that when no chain transfer agent (CCl4) is added; rA and rB are the monomer reactivity ratios of monomers A and B in this system. The cooligomer composition deviated from the statistical steady-state composition on the low molecular weight side, and this deviation was explained by the equation: 相似文献