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61.
Efficient and stereoselective synthesis of a disaccharide fragment, 2-deoxy-4-O-(N'-monodemethyl-D-forosaminyl)-2-methylamino-β-D-xylopyranoside, of a novel antibiotic, incednine (1), is described. The key β-stereoselective formation of a 2,3,4,6-tetradeoxy-4-methylamino glycoside bond was achieved by remote participation-assisted glycosylation. 相似文献
62.
K. Sasaki O. Takahashi N. Takada M. Nagatsu T. Tsukishima T. Okada S. Okajima Y. Tsunawaki S. Sudo K. N. Sato et al. 《International Journal of Infrared and Millimeter Waves》1995,16(12):2133-2146
Spectrally narrow, pulsed outputs consisting of almost a single mode have been obtained from an optically-pumped high-power (200kW) D2O laser by adopting the injection seeding method, where single-mode radiation (seed pulse) from a low-power, compact D2O laser has been injected into the main D2O laser. Spectrally narrow outputs with high power having spectral widths as narrow as 5 MHz have been obtained, when the seed pulses with frequency tuned to one longitudinal mode of the main D2O laser have been injected at a time sufficiently before the lasing of the main laser took place. The experimental results have been compared with those of numerical simulation modified to include the injection field with varying injection times. 相似文献
63.
Yoshimi Yamaguchi Yoshihisa Okamoto Atsushi Takada 《Journal of heterocyclic chemistry》1997,34(6):1737-1739
A novel method for synthesis of a chiral amine borane is described and selective reductions of carbonyl compounds with the amine borane are investigated. 相似文献
64.
65.
K. Umeda T. Yamaya T. Suehiro K. Takimoto R. Wada E. Takada S. Shimoura A. Sakaguchi S. Murakami M. Fukada Y. Okuma 《Nuclear Physics A》1984,429(1):88-104
The differential cross sections for the (d, 6Li) reaction on targets of 12C, 16O, 24Mg, 40Ca, 58Ni and 94Mo have been measured at Ed = 54.2 MeV. The measured angular distributions have been analyzed by finite-range DWBA calculations, and spectroscopic factors for an α-cluster transfer have been extracted. In the DWBA analysis using an optical model with a phenomenological Woods-Saxon potential, the spin-orbit part of the deuteron optical potential played a significant role in reproducing the measured angular distributions but the spin-orbit part of the 6Li optical potential had a minor effect. Relative spectroscopic factors extracted from the present data were compared with theoretical predictions together with the results from the (p, pα) reaction. The relative spectroscopic factors for 1p-shell nuclei were in quantitative agreement with theoretical predictions. However, there were certain discrepancies between the spectroscopic factors extracted from the (d, 6Li) reaction and those from the (p, pα) reaction, and the discrepancies increased with target mass number. 相似文献
66.
Yoshimi Zama Yoshibisa Okamoto Kaname Takagi Yoshihisa Kurasawa Atsushi Takada 《Journal of heterocyclic chemistry》1995,32(3):851-855
The title compound 4 was hydrolyzed to a new type of ynaminonitrile 5 and benzimidazolidines 7 and 9 under acidic or basic conditions. Reaction mechanisms were proposed. 相似文献
67.
68.
H. Ito N. Takada K. Sasaki 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1327-1329
TiO2 films having anatase-type crystal structures were synthesized by reactive laser ablation of a metallic Ti target in ambient O2 gas. The anatase-type TiO2 was obtained at O2 pressures below 0.2 Torr and at substrate temperatures above 150 °C. The films had the (101) orientation at substrate temperatures of 200–250 °C while, at substrate temperatures of 400–450 °C, the orientation of the films was (004). Rutile-type crystal was mixed in at substrate temperatures higher than 450 °C. The synthesis characteristics were compared with the fluxes of Ti, Ti+, and TiO toward the substrate, which were evaluated by laser-induced fluorescence imaging spectroscopy. PACS 81.15.Fg; 61.10.-i; 52.70.Kz 相似文献
69.
70.
A simple atomic-absorption method for determining trace bismuth in copper metal is described. Interference from the matrix is eliminated by masking copper with thiosemicarbazide in acidic solution. 相似文献