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51.
Kohki Fujikawa Tomohiro Nohara Hiromune Ando Hideharu Ishida Makoto Kiso 《Tetrahedron letters》2010,51(7):1126-5815
A cyclic glucosyl ceramide (GlcCer) acceptor has been developed as a versatile building block for the synthesis of complex ganglioside. A macrocyclic GlcCer acceptor, which was the product of intramolecular glycosylation between glucose and ceramide, exhibited high reactivity during the coupling reactions with a variety of complex oligosaccharyl donors, thereby furnishing the corresponding ganglioside frameworks in high yields. 相似文献
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A new theoretical method to calculate the photoionization cross sections of complex molecules and solids is derived in the framework of the dynamical theory by using the Green's function method. The approximations applicable to treat the photoionization by x-rays are also discussed. 相似文献
54.
A facile synthesis of novel 1,2-diazepino[3,4-b]quinoxalines by a 1,3-dipolar cycloaddition reaction
Ho Sik Kim Yoshihisa Kurasawa Chiemi Yoshii Minako Masuyama Atsushi Takada Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1990,27(3):819-822
The 1,3-dipolar cycloaddition reaction of the quinoxaline 4-oxides 4a,b with 2-chloroacrylonitrile gave the 2,3-dihydro-1H-1,2-diazepino[3,4-b]quinoxalines 5a,b , respectively, which were converted into the 2,3,4,6-tetrahydro-1H-1,2-diazepino[3,4-b]quinoxalines 7a,b and 8a,b , respectively. 相似文献
55.
Masashi Ohmae Shun-Ichi Fujikawa Hirofumi Ochiai Shiro Kobayashi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(17):5014-5027
Synthesis of natural and unnatural polysaccharide was achieved via “enzymatic polymerization” by utilizing a glycoside hydrolase as catalyst. Particularly, hyaluronan, chondroitin, and their derivatives belonging to glycosaminoglycans have been prepared using sugar oxazoline monomers designed on the basis of the concept “transition-state analogue substrate”. The oxazoline derivatives of N-acetylhyalobiuronate [GlcAβ(1→3)GlcNAc] and N-acetylchondrosine [GlcAβ(1→3)GalNAc], which have the repeating disaccharide structures of hyaluronan and chondroitin, respectively, were successfully polymerized by the catalysis of hyaluronidase, giving rise to synthetic hyaluronan and chondroitin. Their 2-substituted oxazoline derivatives were also polymerized to the corresponding N-acylated hyaluronan and chondroitin derivatives. Furthermore, N-acetylchondrosine oxazoline derivatives sulfated at the C4, the C6, and both the C4 and C6 of the GalNAc unit were catalyzed by hyaluronidase; the monomer sulfated at the C4 was polymerized to chondroitin 4-sulfate with well-defined structure, whereas the other two monomers were exclusively hydrolyzed to the corresponding disaccharides. These different kinds of natural and unnatural polysaccharides having relatively high molecular weights were produced in all cases by the catalysis of hyaluronidase. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5014–5027, 2006 相似文献
56.
Y. Watanabe N. Yamamoto S. Bhunia T. Kawamura S. Fujikawa 《Physica E: Low-dimensional Systems and Nanostructures》2004,23(3-4):305
Vertically aligned InP nanowires were successfully grown by metalorganic vapor phase epitaxy under metal-catalyzed vapor–liquid–solid growth processes. Au nanoparticles with a nominal diameter of 20 nm were used as the seed to control the diameter of the nanowires. Scanning and transmission electron microscopic studies showed highly dense nanowires with uniform diameters along the length direction, and the zinc-blende structure of the nanowires with 1 1 1 growth direction, respectively. Cathodeluminescence measurements showed a significant blueshift in the spectral peak position compared to bulk InP due to the quantum confinement of the carriers in the nanowires. 相似文献
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Araki T Eguchi K Enomoto S Furuno K Ichimura K Ikeda H Inoue K Ishihara K Iwamoto T Kawashima T Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Ogawa H Owada K Ricol JS Shimizu I Shirai J Suekane F Suzuki A Tada K Tajima O Tamae K Tsuda Y Watanabe H Busenitz J Classen T Djurcic Z Keefer G McKinny K Mei DM Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fu Y Fujikawa BK Goldman J Gray F Heeger KM Lesko KT Luk KB Murayama H Poon AW Steiner HM Winslow LA 《Physical review letters》2005,94(8):081801
We present results of a study of neutrino oscillation based on a 766 ton/year exposure of KamLAND to reactor antineutrinos. We observe 258 nu (e) candidate events with energies above 3.4 MeV compared to 365.2+/-23.7 events expected in the absence of neutrino oscillation. Accounting for 17.8+/-7.3 expected background events, the statistical significance for reactor nu (e) disappearance is 99.998%. The observed energy spectrum disagrees with the expected spectral shape in the absence of neutrino oscillation at 99.6% significance and prefers the distortion expected from nu (e) oscillation effects. A two-neutrino oscillation analysis of the KamLAND data gives Deltam(2)=7.9(+0.6)(-0.5)x10(-5) eV(2). A global analysis of data from KamLAND and solar-neutrino experiments yields Deltam(2)=7.9(+0.6)(-0.5)x10(-5) eV(2) and tan((2)theta=0.40(+0.10)(-0.07), the most precise determination to date. 相似文献
59.
Kazuo Fujikawa 《Zeitschrift fur Physik C Particles and Fields》1982,15(3):275-280
We comment on some of the general thermostatistical properties of the global supersymmetry characterized by Grassmann parameters, which are shared by the ordinary supersymmetry as well as by the BRS supersymmetry associated with any gauge symmetry including local supersymmetry. 相似文献
60.
Shiro Hirota Takashi Fujikawa 《Journal of Electron Spectroscopy and Related Phenomena》1982,28(1):95-109
Dynamic theory developed previously by the authors is applied to photoionization from delocalized molecular orbitals. EXAFS-like oscillation is observed in any case, but the origin, period and magnitude differ from those of EXAFS usually observed in core photoionization. Numerical calcu- lations are performed in the energy range k = 3–6 a.u. for three molecules: H2O, CO and CO2. Analysis of such oscillatory behavior aids in the characterization of photoionized orbitals. 相似文献