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101.
Sadao Arai Hitoshi Arai Kunihisa Tabuchi Takamichi Yamagishi Mitsuhiko Hida 《Journal of heterocyclic chemistry》1992,29(1):215-220
Six isomers of the methylbenzo[c]quinolizinium salt 3 including four new monomethyl derivatives were synthesized by thermal-intramolecular quaternization of the cis-methyl-substituted 2-[2-(2-chlorophenyl)-vinyl]pyridines 4 or by the irradiation of trans- 4 with selected wavelengths (290 < λ < 340 nm and λ > 400 nm) in acetonitrile. Among the regioisomeric monomethyl derivatives 3 , the 1-, 3-, and 6-methyl derivatives 3b, 3d , and 3g reacted with p-methoxybenzaldehyde in the presence of bis(l-piperidino)-(p-methoxyphenyl)-methane 7 to yield trans-(p-methoxystyryl)benzo[c]quinolizinium salts 6 . The reactivity of 3 and methylbenzo[a]quinolizinium salts 1 was discussed on the basis of their π-electron energy. 相似文献
102.
David M. Lange Gary W. Poehlein Sadao Hayashi Akihiko Komatsu Toshihiro Hirai 《Journal of polymer science. Part A, Polymer chemistry》1991,29(6):785-792
Particle number and size data from a series of seeded, emulsifier-free, vinyl acetate emulsion polymerization experiments have been analyzed with the aid of polymerization and particle growth models. A secondary population of particles, with a significantly greater number concentration than the seed, was nucleated in all experiments. The two populations (seed and new) had rather narrow size distributions and large diameters. Hence the reactions were in the area normally associated with Smith–Ewart Case III kinetics. Water-phase termination reactions can be important in this reaction region but radical desorption from such large particles does not significantly influence the kinetics. The results of the analysis were used to evaluate the magnitude of water-phase termination; to estimate radical capture coefficients; and to evaluate competitive particle growth. 相似文献
103.
Keitaro Senga Yukako Kanamori Hashime Kanazawa Sadao Nishigaki 《Journal of heterocyclic chemistry》1978,15(3):359-363
Treatment of 1,3-dimethyl-6-hydrazinouracil with the appropriate dimethylformamide dialkylacetal afforded the, corresponding 2-alkyl-5,7-dimethylpyrazolo[3,4-d]pyrimidine-4,6-(5H,7H)diones. The reaction of 1,3-dimethyl-6-(α-methylbenzylidenehydrazino)uracils with dimethylformamide dimethylacetal or triethyl orthoformate gave the corresponding 5,7-dimethyl-2-vinylpyrazolo[3,4-d]pyrimidine-4,6(5H,7H)diones, respectively. Similarly, treatment of 1,3-dimethyl-6-(α-methylbenzylidenehydrazino)uraeils with triethyl orthopropionate yielded the corresponding 5,7-dimethyl-3-ethyl-2-vinylpyrazolo[3,4-d]pyrimidine-4,6(5H,7H)diones. 相似文献
104.
Sadao Araki Norito Mohri Yuichi Yoshimitsu Yoshikazu Miyake 《Journal of membrane science》2007,290(1-2):138-145
Cylindrical silica membranes with dead-end structure were prepared by an extended counter-diffusion chemical vapor deposition (CVD) method, in which a tetramethylorthosilicate (TMOS) silica source was fed from the outside of a cylindrical membrane support with γ-alumina interlayer (the membrane side), and oxygen gas was fed from the inside (the support side). Extended counter-diffusion CVD is a method of depositing silica films under highly pressurized conditions applied to the membrane side where TMOS is supplied. Two silica membranes were deposited for 10 h at 573 K under differential pressures of 0.1 MPa and 0.0 MPa applied between the cylindrical membranes. The hydrogen permeances for these silica membranes were unaffected (5 × 10−8 mol m−2 s−1 Pa−1 at 573 K), although the methane and carbon dioxide permeances were greatly reduced for dense silica films prepared by high-pressure CVD (HPCVD). Therefore, the selectivity of hydrogen over methane and carbon dioxide was 24,000, and 1200, respectively. It is suggested from energy dispersive X-ray microanalysis (EDX) observations in scanning electron microscopy (SEM) and scanning probe microscopy (SPM) results that this high selectivity was due to the reduced number of defects and/or pinholes formed in the dense silica membranes by HPCVD. 相似文献
105.
A new TEMPO-mediated catalytic oxidation method in combination with Py·HBr3 (stoichiometric) is developed for oxidation of secondary alcohols to the corresponding ketones. The performance of this oxidizing system is better compared with that of TEMPO method combined with R4NBr3. Poly(4-vinylpyridine)·HBr3 can be used in place of Py·HBr3. The electron-withdrawing substituent at the C-4 position of TEMPO increases the reactivity of TEMPO significantly in the oxidation of electron-deficient alcohols such as polyhaloalkylmethanols. Inductive effect of the substituent of TEMPO is discussed through the characterization of the redox potential of N-O radical by cyclic voltammetry. 相似文献
106.
107.
Resonant Brillouin scattering in CdS by piezoelectrically inactive TA phonons has been studied at room temperature in the region of photon energies very close to the fundamental absorption edge. The results have shown that the scattering efficiency depends strongly on the damping in the excited electronic states. 相似文献
108.
Sadao Oida Akira Yoshida Teruo Hayashi Eiji Nakayama Sadao Sato Eiji Ohki 《Tetrahedron letters》1980,21(7):619-620
The structure for the fused β-lactam obtained by treatment of the secolactam with base in the presence of Cu(I)-ion is not the penem (R=CH3), but the isopenem on the basis of X-ray analysis. 相似文献
109.
Ogata Yoshimune Itadzu Hidesuke Kojima Sadao 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(3):1145-1149
Journal of Radioanalytical and Nuclear Chemistry - The new sum peak method was applied to the samples containing both 137Cs and 134Cs using a well-type HPGe detector. The standard sources... 相似文献
110.
Hiroshi Komoto Fusakazu Hayano Toshio Takami Sadao Yamato 《Journal of polymer science. Part A, Polymer chemistry》1971,9(10):2983-2995
The synthetic route to 1,2-bis(4-aminocyclohexyl)ethane from toluene via p-nitrotoluene and p,p′-dinitrodibenzyl was established. The distribution of geometric isomers was estimated by NMR and fractional recrystallization. Polyamides were synthesized from 1,2-bis(4-aminocyclohexyl)ethane and dodecanedioic or sebacic acid. Polymer melting temperatures were varied with isomer compositions. A high content of the trans conformation causes high melting temperatures. Glass transition temperatures of polyamides were in the range of 105–120°C and were less sensitive to isomer compositions. 相似文献