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141.
142.
Yasuhiro Kajihara Hironobu Hashimoto Hisashi Kodama Tomio Wakabayashi Ken-ichi Sato 《Journal of carbohydrate chemistry》2013,32(7):991-995
Abstract Specific inhibitors of glycosyltransferases have become of interest1 not only for investigation of carbohydrate-participating cell-surface phenomena but also for practical use such as chemotherapeutic reagents. Glycosyltransferases catalyze the transfer of glycosyl moieties from nucleotide donors to oligosaccharide acceptors. Therefore, two kinds of substrate-analog inhibitors are possible. The donor analogs have been rather well studied, but are not specific. On the other hand, glycosyltransferases have in general smct acceptor specifkity. Recently, acceptor analogs which inhibit the corresponding glycosyltransferases were reported2-5 and as expected were acceptor-specific inhibitors. 相似文献
143.
Shin AidaKimitada Terao Yasuhiro NishiyamaKiyomi Kakiuchi Michael Oelgemöller 《Tetrahedron letters》2012,53(42):5578-5581
The continuous-microflow photochemical synthesis of terebic acid from maleic acid was investigated in two different microreactor set-ups. The results were subsequently compared to analogue experiments in a conventional chamber reactor. Based on conversion rates, reactor design and energy efficiency calculations, the simple microcapillary reactor showed the best overall performance. 相似文献
144.
145.
Liping Lou Yasuhiro Koike Yoshiyuki Okamoto 《Journal of polymer science. Part A, Polymer chemistry》2010,48(22):4938-4942
2,3,4,5,6‐Pentafluoro and 4‐trifluoromethyl 2,3,5,6‐tetrafluoro styrenes were readily copolymerized with methyl methacrylate (MMA) by a free radical initiator. The copolymers were soluble in tetrahydrofuran and acetone. The films obtained were transparent and flexible. The glass transition temperatures (Tgs) of the copolymers were found positively deviated from the Gordon–Taylor equation. The positive deviation could be accounted for by dipole–dipole intrachain interaction between the methyl ester group of MMA and the highly fluorinated aromatic moiety, which resulted in a decrease in the segmental mobility of the polymer chains and the enhanced Tg values of the copolymers. The water absorption of PMMA was greatly decreased by copolymerization of MMA with the highly fluorinated styrenes. With as little as 10 mol % of pentafluoro styrene content in the copolymer, the water absorption was decreased to one‐third of that for pure PMMA. The fluorinated styrenes‐MMA copolymers were thermally stable up to 420 °C under air and nitrogen atmospheres. With 50 mol % of MMA in the copolymer, the copolymer was still stable up to 350 °C. Since these copolymers contain a large number of fluorine atoms, the light absorption in the region of the visible to near infrared is decreased in comparison with nonfluorinated polymers. Thus, these copolymers may be suitable for application in optical devices, such as optical fibers and waveguides. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
146.
Hironori Ohashi Hiroyuki Ezoe Yoshihiro Okaue Yasuhiro Kobayashi Shuji Matsuo Tsutomu Kurisaki Akane Miyazaki Hisanobu Wakita Takushi Yokoyama 《Analytical sciences》2005,21(7):789-793
The effect of UV (ultraviolet) irradiation on the adsorption of Au(III) ions on manganese dioxide and their reduction to Au(0) (gold with 0 valence state) was investigated using XPS (X-ray photoelectron spectroscopy) and 197Au M?ssbauer spectroscopy. The UV irradiation accelerated the adsorption and the reduction. From the fact that the proportion of Au(0) estimated from Au 4f XPS spectra for surface analysis was significantly smaller than that from 197Au M?ssbauer spectra for bulk analysis, we deduced that Au(0) was interpenetrated to the inside of manganese dioxide (into deeper places than about 30 A) where XPS is impossible to detect. The content of surface hydroxyl groups on manganese dioxide also increased due to the UV irradiation. The relationship between the charge in the content of hydroxyl groups and the interpenetration of Au(0) is discussed. 相似文献
147.
We successfully demonstrated low power penalty operation of a cross-phase modulated (XPM) wavelength converter using a semiconductor optical amplifier (SOA) power equalizer. We also clarified the SOA equalizing level for more adaptive wavelength conversion and achieved a power penalty of less than 1 dB over the wide input dynamic range of 15 dB. 相似文献
148.
Naoto Sugimoto Seiji Fukushima Yasuhiro Suzuki Yoshihisa Sakai Hiromasa Tanobe Takeshi Kurosaki Kazuto Noguchi Kimio Oguchi Hiromu Toba 《光学学报》2003,23(Z1)
A new generation of network interface card for fiber-to-the-desktop has been fabricated. The fabricated card is PC-card size and suitable for notebook PCs. It could become the key element in the coming optical Ethernet age. 相似文献
149.
8-Hydroxyquinoline derivative 1 as a fluorescent chemosensor for Zn2+ was synthesized. Because Cd2+ is often found with Zn2+ in the environment and can form fluorescent complexes with chelating fluorophores, a potentially important property of chemosensors for Zn2+ is their selectivity for Zn2+ over Cd2+. The Zn2+ or Cd2+ complexes of 1 gave an emission band from the 1:1 complex, but the fluorescence intensity for Cd2+ was a half of that for Zn2+. Ligand 1 is suited for use as a fluorescent chemosensor for Zn2+. 相似文献
150.
Ramachandran Saravanan Yasuhiro Ono Kahoru Ohno 《Journal of Physics and Chemistry of Solids》2003,64(1):51-58
Electron density distribution of GaAs is determined by means of the maximum entropy method (MEM) using reasonably good X-ray data collected at room temperature and 200 K. The bonding electron distributions are clearly visible in the MEM map and the mixed covalent-ionic character in GaAs is evidenced. The density distributions at 200 K show more condensed electronic clouds as compared to the room temperature map, preserving the trend in the bonding characters. The electron densities at the middle of the bond are 0.79 and 0.70 e/Å3 at 200 K and at room temperature, respectively. The refined harmonic thermal factors are in good agreement with the published values. 相似文献