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931.
Masato Takeuchi Kouichirou Tsujimaru Kenji Sakamoto Masaya Matsuoka Hiromi Yamashita Masakazu Anpo 《Research on Chemical Intermediates》2003,29(6):619-629
Platinum-loaded titanium oxide thin-film photocatalysts were prepared by using an ionized cluster beam (ICB) deposition method and a RF magnetron sputtering (RF-MS) deposition method as dry processes. From the results of the photocatalytic oxidation of acetaldehyde with O2 under UV light irradiation, small amounts of Pt loading (less than 10 nm film thickness) were found to dramatically enhance the photocatalytic reactivity. However, when TiO2 thin films were loaded with relatively larger amounts of Pt (more than 30 nm as the film thickness), the photocatalytic reactivity became lower than for the pure TiO2 thin films. Moreover, investigations of the ratio of Pt loaded onto the surface of the thin film catalysts by XPS measurements revealed that the small amounts of Pt loaded exist as very small clusters working to efficiently enhance the charge separation, whereas, large amounts of Pt covers the entire surface of the TiO2 thin films, resulting in a decrease of the photocatalytic reactivity. 相似文献
932.
Ryoji Inaba Takayuki Fukahori Masato Hamamoto Teruhisa Ohno 《Journal of molecular catalysis. A, Chemical》2006,260(1-2):247-254
Nanosized pure TiO2 particles with high crystallinity and large surface area were prepared by hydrolysis of tetrabutyl titanate in water/Triton X-100/isooctane reverse micelle solutions as reaction media followed by hydrothermal treatment to improve crystallinity. The prepared TiO2 nanoparticles were characterized by XRD, BET, TGA, FT-IR and TEM. The size of ultrafine particles was controlled by changing the water content of the reverse micelle solution. The TiO2 particles showed monodispersity, large surface area and high degrees of crystallinity and thermostability. The photocatalytic activity of the TiO2 particles was evaluated by decomposition of toluene in the gas phase. The activity of the TiO2 nanoparticles was higher than that of commercially available anatase fine particles, such as ST-01, which is one of the most active photocatalysts for degradation of organic compounds in the gas phase. 相似文献
933.
Highly efficient isomerization of allylic alcohols into saturated carbonyls is accomplished using the catalyst system of Cp*RuCl[Ph2P(CH2)2NH2-kappa2-P,N]-KOt-Bu (Cp* = eta5-C5(CH3)5) under mild conditions. Mechanistic consideration based on isotope-labeling experiments indicated the present reaction is applicable to the asymmetric isomerization of racemic sec-allylic alcohols with a prochiral olefin via dynamic kinetic resolution. A concise asymmetric synthesis of muscone has been achieved, where the asymmetric isomerization using an optically active ligand is a key reaction. 相似文献
934.
13C-NMR spectral data on 6-aminohexyl glycosides of -β--galactopyranosyl-2-acetamido-2-deoxy-β--glucopyranose are pr 相似文献
935.
Masato Mizutani Yuzuru Sanemitsu Yoshinao Tamaru Zen-ichi Yoshida 《Tetrahedron letters》1985,26(9):1237-1240
Selective transformation of 3-propargylthio-1,2,4-triazin-5(2H)-ones () to 6-methylene-6,7-dihydro-4H-thiazolo[2,3-c][1,2,4]-triazin-4-ones () and 3-methylene-2,3-dihydro-7H-thiazolo[3,2-b]-[1,2,4]triazin-7-ones () is performed under the conditions of Pd(II) salt or sodium hydroxide catalysis, respectively. 相似文献
936.
Mototeru Yamane Akihisa Abe Shinsuke Shimizu Masato Nakajima 《Journal of chromatography. A》1996,730(1-2):91-98
A homogenate of rat brain, rat liver or human colonic well differentiated adenocarcinoma was prepared in 250 mM sucrose isoosmolaric buffer (pH 7.6) and fractionated by differential centrifugation at 103, 104 and 105 g. Each precipitate or supernatant was incubated with NADPH and docosahexaenoic acid or arachidonic acid as a substrate for 30 min at 37°C under aerobic conditions. ω-Hydroxydocosahexaenoic acid or ω-hydroxyeicosatetraenoic acid from an incubation mixture was detected by reversed-phase high-performance liquid chromatography-thermospray mass spectrometry with selected-ion monitoring. ω-Hydroxy polyunsaturated fatty acids were characterized by high intensity of the molecular ion (MH+) although common hydroxy polyunsaturated fatty acids were characterized by high intensity of the MH+ - H2O ion. For the rat brain, ω-hydroxylation activity (the amount of ω-hydroxy product produced in 30 min) was concentrated to a 103 g precipitate although the specific activity (the activity per 1 mg of protein) in the 103 g precipitate did not indicate superiority over other fractions. However, the specific activity of the rat brain increased on addition of a 104 or 105 g precipitate. For the rat liver, although ω-hydroxylation activity was concentrated to a 103 g precipitate, the specific activity was concentrated to a 105 g precipitate and the Subcellular localization differed from that of rat brain. In the human colonic well differentiated adenocarcinoma, although ω-hydroxylation activity was relatively high in the 103 g supernatant, the specific activity was relatively high in the 103 and 105 g precipitates. These results suggest that there is a difference regarding subcellular localization of the ω-hydroxylation activity depending on the species of the organs. 相似文献
937.
Nakamura Y Suzuki M O-kawa K Konno T Nishimura J 《The Journal of organic chemistry》2005,70(21):8472-8477
The photoreactions of [60]fullerene with aromatic tertiary amines such as N,N-dimethylaniline and N,N-dimethyl-1-naphthylamine gave two or three types of [60]fullerene adducts. The reaction efficiency in the series of p-substituted N,N-dimethylanilines remarkably increased with increasing electron-donating properties of aromatic tertiary amines employed. 相似文献
938.
Sclerosporin, the major sporogenic substance of , and its related metabolite, sclerosporal, were shown to have the plain structures, , and , respectively. by using a micro-amount of the samples, and co-occurring sclerosporene probably to have the structure . 相似文献
939.
Hiroyoshi Kamogawa Yasuto Todo Masato Nanasawa 《Journal of polymer science. Part A, Polymer chemistry》1981,19(10):2571-2579
Vinyl monomers bearing phenoxazine units, were synthesized: 2-vinyl-phenoxazine starting with phenoxazine in a five-step synthesis; 3-acrylamido- or 3-methacrylamido-phenoxazines with or without 10-PhCH2 or 10-Me-substituent starting with o-benzylideneaminophenol or o-anisidine via 3-aminophenoxazines; and 3-(p-styrenesulfonamido)phenoxazines with or without 10-PhCH2- or 10-Me-substituent, also via 3-aminophenoxazines. Polymerizations of these noval monomers proceeded smoothly, except those having no 10-substituent. Changes of the visible absorption spectrum of iodine in THF with addition of the polymers and oligomers thus prepared were considerable, with the appearance of new absorption peaks for polymers with 10-Me-substituent. 相似文献
940.
Fluorous-tagged compounds can rapidly be separated from organic (non-tagged) compounds by the new separation technique of reverse fluorous solid-phase extraction (r-fspe). In a reversal of the roles of solid and liquid phases in standard fluorous spe, a mixture is charged to a polar solid phase (standard silica gel) and then eluted with a fluorous solvent or solvent mixture. The organic components of the mixture are retained, while the fluorous components pass. [structure: see text] 相似文献