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41.
Yutaka Maniwa Yoshinori Kumazawa Yumi Saito Hideki Tou Hiromichi Kataura Hiroyoshi Ishii 《Molecular Crystals and Liquid Crystals》2013,570(1):671-676
Abstract X-ray diffraction (XRD) and electrical resistance measurement on single-walled carbon nan-otube (SWNT) samples prepared by the arc-discharge method are reported. The XRD profile of heat-treated sample indicated that air (oxygen, and/or nitrogen and/or water) can be condensed inside the SWNTs. We also found that the electrical resistance of SWNT soot is significantly affected by exposing to the oxygen gas and humid air. 相似文献
42.
Andreas Meissner Takayuki Kishi Yuka Fujisawa Yuto Murai Hiroyoshi Takamura Isao Kadota 《Tetrahedron letters》2018,59(51):4492-4495
A stereoselective formal total synthesis of enigmazole A, a marine macrolide isolated from Cinachyrella enigmatica, is described. Lewis acid mediated intramolecular allylation of an α-acetoxy ether, prepared from alcohol and carboxylic acid fragments was carried out to construct the methylene THP ring with high stereoselectivity. The late-stage macrolactonization of the corresponding seco-acid provided a known synthetic intermediate of enigmazole A. 相似文献
43.
Ei-ichi Nishizawa Leenawaty Limantara Noriyuki Nanjou Hiroyoshi Nagae Tomisaburo Kakuno Yasushi Koyama 《Photochemistry and photobiology》1994,59(2):229-236
The frequency of BChl that was bound to the light-harvesting complex (LHC) of Rhodobacter sphaeroides R26 was found to be 1598 cm-1 , a result which suggests that a pair of BChl molecules form a dimer in the LHC in the T1 state. 相似文献
44.
Hiroyoshi Kamogawa Kunimichi Kitahora Hidehito Hanawa Masato Nanasawa 《Journal of polymer science. Part A, Polymer chemistry》1976,14(5):1235-1240
Several polymerizable hydroquinone derivatives were prepared by the Williamson synthesis. Thus, hydroquinone mono(p-vinylbenzyl) ether (III-1), hydroquinone methyl p-vinylbenzyl ether (III-4), and hydroquinone benzyl p-vinylbenzyl ether (III-5), tert-butylhydroquinone mono(p-vinylbenzyl) ether (III-2), and 2,5-di-tert-butylhydroquinone mono(p-vinylbenzyl) ether (III-3) were synthesized by the reactions of p-chloromethylstyrene with the corresponding hydroquinone derivatives in alcoholic potassium hydroxide or with their potassium salts in dipolar aprotic solvents. All monomers were found to polymerize by free-radical initiation except III-3, which required a cationic initiator. 相似文献
45.
46.
Kazuaki Fukamichi Hidetoshi Hiroyoshi Michio Kikuchi Tsuyoshi Masumoto 《Journal of magnetism and magnetic materials》1979,10(2-3):294-299
The thermal expansion and magnetic properties of Fe-B and Fe-P amorphous alloys prepared from melts have been investigated. These amorphous alloys show distinct Invar characteristics. heir magnetic properties are also very similar to those of Fe-Ni crystalline Invar alloys; that is, the high-field susceptability and forced-volume magnetostriction are remarkably large, the magnetic moment per Fe atom does not increase linearly, the Curie temperature decreases with a decrease in concentration of B or P, and their reduced their magnetization curves are much flatter than those of crystalline pure Fe. 相似文献
47.
Y. Nakagawa Y. Tanji H. Morita H. Hiroyoshi H. Fujimori 《Journal of magnetism and magnetic materials》1979,10(2-3):145-151
Fe-Ni Invar alloys exhibit anomalies in thermodynamic and physical properties at high temperatures. This is considered to result from the tendency to two-phase separation in the fcc phase. This idea is supported also by interdiffusion experiments in the Fe-Ni system, where the interdiffusion coefficient is anomalously small in the Invar region at lower temperatures. A simple theory of regular solutions based on a pair interaction model is applied to the Fe-Ni system; with the assumption of two gamma states this gives a miscibility gap in the Invar region. 相似文献
48.
49.
(+)-Cerulenin was synthesized stereoselectively from D-glucose. 相似文献
50.
Four kinds of vinyl polymers containing N-substituted phenothiazinyl groups in side chains were obtained by syntheses of the respective monomers and subsequent polymerizations. Thus, N-acrylamidomethylphenothiazine, N-(N-acrylamidomethyl)carbamoylethyl phenothiazine, β-(N-phenothiazinyl)ethyl acrylate and methacrylate, and β-(N-phenothiazinyl)ethyl vinyl ether were synthesized. It was found that all monomers except the last monomer can be polymerized with typical free-radical initiators such as α,α′-azobisisobutyronitrile to afford stable soluble polymers with electron-donating characteristics, presumably due to the absence of a hydrogen atom at the site of the nitrogen atom of the phenothiazinyl group. The last monomer was found to be susceptible to typical cationic initiators such as boron trifluoride etherate to afford a stable soluble polymer also with the electron-donating characteristic. 相似文献