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61.
Mikio Hori Tadashi Kataoka Hiroshi Shimizu Sachio Ohno Kenichi Narita Hiroaki Takayanagi Haruo Ogura Yoichi Iitaka 《Tetrahedron letters》1979,20(44):4315-4318
The first success of an X-ray analysis of a thiabenzene derivative, 1-benzoyl-2-methyl-2-thianaphthalene is described. 相似文献
62.
H. Ogura 《Chemistry of Heterocyclic Compounds》1981,17(7):633-641
Primarily the studies of the author dealing with the synthesis of analogs of nucleosides by cyclization of derivatives of monosaccharides, viz., Schiff bases, hydrazones, thioureas, thiocarbamates, thiosemicarbazones, thiobiurets, and keto isothiocyanates, are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 867–877, July, 1981. 相似文献
63.
We examined whether a protein could catalyze two-phase oxidation of formaldehyde dithioacetals with aqueous sodium metaperiodate and bovine serum albumin was found to be effective and give the corresponding S-oxides in optically active forms. 相似文献
64.
Tadahiro Minamikawa Seido Ogura Tetsuo Sakka Yukio Ogata Matae Iwasaki 《国际化学动力学杂志》1994,26(5):561-569
Photolysis of CClF2CH2Cl was studied by 147 nm vacuum ultraviolet irradiation. In the presence of NO; CF2CH2, CF2CHCl, and CClF2CN were produced. These products represent three different reaction paths; the molecular dechlorination, molecular dehydrochlorination, and chlorine radical elimination reactions. The reactant pressure and the addition gas (He or NO) pressure effects upon the product yield were studied. © 1994 John Wiley & Sons, Inc. 相似文献
65.
Tomoya Ito Koji Suda Takuya Kumamoto Waka Nakanishi Toshiko Watanabe Tsutomu Ishikawa Hiroko Seki Masatoshi Kawahata Kentaro Yamaguchi Yasumitsu Ogura Kazuo T. Suzuki 《Molecular diversity》2010,14(1):131-145
The role of o-bisguanidinobenzenes (BGBs) as new Brønsted base ligands for arsenic and phosphoric acids was examined. In solution state, complexation was evaluated by Job’s plot in 1H NMR experiment, indicating a 1:1 complex formation, whereas in solid state crystalline structures of complexes obtained were addressed by X-ray crystallographic analysis and/or solid state 13C NMR experiment, in which 1:2 complexes between the BGB and the acid components were normally formed. Based on these results, Merrifield and Hypogel® resin-anchored BGBs were designed and prepared as the corresponding polymer-supported host ligands. Evaluation of their coordination ability with metal salts (ZnCl2 and CoCl2) and arsenic acid in aqueous media by ICP-MS showed that the latter Hypogel® resin-anchored BGBs acted as effective immobilized base ligands. 相似文献
66.
The possibility of half-metallic antiferromagnetism, a special case of ferrimagnetism with a compensated magnetization, in the diluted magnetic semiconductors is highlighted on the basis of the first-principles electronic structure calculation. As typical examples, the electrical and magnetic properties of II-VI compound semiconductors doped with 3d transition metal ion pairs--(V, Co) and (Fe, Cr)--are discussed. 相似文献
67.
Successive differential and integral sorptions of water vapor into the polyelectrolyte complex of poly (sty renesulfonic acid) / poly(4-vinyl-N-ethylpyridinum bromide) have been measured; films of stoichiometric (1/1 molar ratio) and nonstoichiometric (2/1 molar ratio) complex were employed in the experiments. Sorption isotherms have been also determined by using the values obtained from integral sorption experiments. The sorption data have suggested the following. (i) The rearrangement of polymer chains plays a relatively unimportant role in sorption of water. (ii) The relaxation motion of network chains is suppressed. (iii) The change of morphological structure caused by vapor sorption is obscure. (iv) The ionic character of the 1/1 complex is higher than that of 2/1 complex. (v) A small amount of water can be dispersed on specific polymer sites, but the sorption of a large amount of water is accompanied by an expansion of network structure. Points (i)-(v) have been consistently interpreted on the basis of the network structure and ionic character of this complex. 相似文献
68.
We firstly discuss the topological properties of the space of upper semicontinuous functions, and then we obtain large deviation principles for random upper semicontinuous functions under various topologies. Finally, we prove moderate deviation principles for random sets and random upper semicontinuous functions. 相似文献
69.
Hiroki Soeda Ryo Towada Yusuke Ogura Tomoyo Mohri Georg Pohnert Shigefumi Kuwahara 《Tetrahedron》2019,75(11):1555-1562
The proposed structure for a moss-produced acetylenic oxylipin (10-keto-type structure) was synthesized from a known glycidol derivative by an 11-step sequence involving epoxide ring opening with a terminal acetylene and enzymatic hydrolysis of a methyl ester intermediate. The NMR spectra of the proposed structure was, however, different from those of the natural oxylipin, which prompted us to synthesize its 9-epi-isomer and two diastereomeric 12-keto-type positional isomers. Comparison of the NMR spectra of the three isomers with those of the natural oxylipin indicated that the natural oxylipin was actually a mixture of the two diastereomeric positional isomers. 相似文献
70.
A. Ogura T. Yoshida Y. Kakemura M. Higuchi A. Teramoto T. Hattori 《Applied Surface Science》2008,254(19):6229-6231
The stresses at Si3N4/Si (1 0 0), (1 1 1) and (1 1 0) interfaces were measured by UV Raman spectroscopy with a 364 nm excitation laser whose penetration depth into the Si substrate was estimated to be 5 nm. The Si3N4 films were formed on Si (1 0 0), (1 1 1) and (1 1 0) using nitrogen-hydrogen (NH) radicals produced in microwave-excited high-density Xe/NH3 mixture plasma. The localized stress detected from Raman peak shift was compressive at the (1 0 0) interface, and tensile at the (1 1 1) and (1 1 0) interfaces. The results showed that stress had strong correlation with the total density of subnitrides at the Si3N4/Si interface, and also with the full-width at half-maximum (FWHM) of Si the 2p3/2 photoemission spectrum arising from the substrate. We believe that the localized stress affected subnitride formation because the amount of subnitride and the FWHM of Si 2p3/2 decreased while the interface stress shifted in the tensile direction. 相似文献