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991.
Hitoshi Inoue 《Physics letters. A》2000,270(6):1544-366
We investigate the S=1/2 XXZ spin chain with period 3 magnetic field term. The magnetization plateau-nonplateau transition at m=±1/6 is expected to be of the Berezinski–Kosterlitz–Thouless type from the bosonization argument. By examining the level crossing of low-lying excitations numerically, we precisely determine the plateau phase diagram. 相似文献
992.
993.
Kei Wakabayashi Yasuhiro Maeda Kazuhiko Ozutsumi Hitoshi Ohtaki 《Journal of Molecular Liquids》2004,110(1-3):43-50
The solvation structure of chloride, bromide, and iodide ions, X−, in dimethyl sulfoxide (DMSO) has been investigated by using Raman spectroscopy and large angle X-ray diffraction under ambient conditions. The positively charged sulfur atom in DMSO interacts with X− and slightly positively charged methyl groups in the coordinating molecules also interact with X−. The X−---S, X−···C, and X−···O distances are determined as follows: Cl−---S: 416, Cl−···C: 363, Cl−···O: 543, Br−---S: 433, Br−···C: 372, Br−···O: 544, I−---S: 437, I−···C: 374 and I−···O: 520 pm. The coordination numbers of DMSO molecules around the anions are six, seven and eight for Cl−, Br− and I− ions, respectively, with the uncertainty of ±1. Rather large uncertainties in the measured solvation numbers suggest large fluctuations in the solvation structure of the anions. 相似文献
994.
A rigidity theorem for a statistical hypersurface of Hesse–Einstein type is given. 相似文献
995.
996.
The formyl group at the 3-position of methyl pyropheophorbide-d, one of chlorophyll-a derivatives, was efficiently transformed to the 32-cis-unsubstituted/methyl- or 32-cis-phenyl-32-trans-nitro-vinyl groups by Henry (nitro-aldol) or nitro-Mannich (aza-Henry) reactions with nitromethane/ethane or nitrophenylmethane, respectively. The introduction of a nitro group at the terminal of the 3-ethenyl moieties directly connected with the chlorin π-system red-shifted and broadened their Qy electronic absorption and fluorescence emission bands in a solution. The fluorescence intensities were largely suppressed by the substitution with the nitro group. 相似文献
997.
Kazuyoshi Yoshimi Hitoshi Seo Shoji Ishibashi Stuart E. Brown 《Physica B: Condensed Matter》2012,407(11):1783-1786
We theoretically investigate the effects of charge order and spin frustration on the spin ordering in TMTTF salts. Using first-principles band calculations, we find that a diagonal inter-chain transfer integral tq1, which causes spin frustration between the inter-chain dimers in the dimer-Mott insulating state, strongly depends on the choice of anion. Within the numerical Lanczos exact diagonalization method, we show that the ferroelectric charge order changes the role of tq1 from the spin frustration to the enhancement of the two-dimensionality in spin sector. The results indicate that tq1 assists the cooperative behavior between charge order and antiferromagnetic state observed in TMTTF2SbF6. 相似文献
998.
Stable high-molecular-weight polyacetals can be prepared from formaldehyde or from its trimer trioxane. 相似文献
999.
Akira Hasegawa Takao Nagahama Hitoshi Ohki Makoto Kiso 《Journal of carbohydrate chemistry》2013,32(6):699-714
Abstract A stereocontrolled, facile total synthesis of ganglioside GM2 is described. Coupling of 2- (trimethylsilyl)ethyl O-(2,6-di-O-benzyl-(β-D-galactopyranosyl)-(1→4)-2,3,6-tri-O-benzyl-β-D-glucopyranoside (2), prepared from 2-(trimethylsilyl)ethyl β-lactoside (1) by selective 3′,4′-O-isopropylidenation, O-benzylation, and subsequent removal of the isopropylidene group, with methyl (methyl 5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy -2-thio-D-glycero-D-galacto -2-nonulopyranosid)onate (4) using N-iodosuccini-midc (NIS), gave the trisaccharide (5), which on condensation with methyl 6-O-benzoyl -2-dcoxy-3,4-O-isopropylidene-2-phthalimido-l-thio-β-D-galactopyranoside (11), gave the protected ganglioside GM2 oligosaccharide 12. Compound 12 was transformed, via O-deisopropylidenation, O-acetylation, removal of the phthaloyl group, N-acetylation, removal of the benzyl groups followed by (O-acetylation, selective removal of the 2-(rximethylsilyl)ethyl group, and subsequent imidate formation, into the final glycosyl donor 19. Glycosylation of (2S,3R,4E)-2-azido-3-O-benzoyl-4-octadecene-l,3-diol (20) with the α-trichloroacetimidate 19 gave the β-glycoside 21, which on channeling through selective reduction of the azide group, coupling of the amino group with octadecanoic acid, O-deacylation and saponification of the methyl ester group, gave the title ganglioside. 相似文献
1000.
Sunao Shoji Takeshi Hashishin Prof. Hitoshi Tamiaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(42):13544-13544