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排序方式: 共有162条查询结果,搜索用时 46 毫秒
31.
Sato S Nakamura T Nitobe S Kiba T Hosokawa K Kasajima T Otsuka I Akimoto S Kakuchi T 《The journal of physical chemistry. B》2006,110(43):21444-21449
Dimethylanthracene (DMA), which exhibits almost no self-association in bulk organic solvents, forms a dimer and emits excimer-like fluorescence in a gamma-cyclodextrin nanocavity in a dilute aqueous solution. The 1Bb and 1La electronic transitions of the DMA dimer split by 2230 and 344 cm(-1), respectively, in a fluorescence excitation spectrum obtained with the excimer-like emission. From these energy splits, the structure of dimer in relation to a dielectric constant inside gamma-CD was discussed on the basis of atom-atom Lennard-Jones potential calculations including Coulombic interactions. Excitation relaxations of DMA in the presence of alpha-, beta-, and gamma-CDs in aqueous solutions were investigated by time-resolved fluorescence. The results suggest that both the hydrated and anhydrated species exist in the alpha- and gamma-CD complexes, while only the anhydrated species exists in the beta-CD complex. 相似文献
32.
Shin-ichiro Kurimoto Yurika Iinuma Junichi Kobayashi Takaaki Kubota 《Tetrahedron letters》2018,59(51):4496-4499
A new 12-membered macrolide, symbiodinolactone A, was isolated from the culture broth of symbiotic marine dinoflagellate Symbiodinium sp. The gross structure of symbiodinolactone A was elucidated by spectroscopic analyses, and the relative configuration was elucidated by the J-based configuration analysis and density-functional theory calculations. Symbiodinolactone A is the new 12-membered macrolide possessing an E double bond between C-4 and C-5, a branched methyl group at C-7, and a 1,2,3-trihydroxybutyl group at C-11. Symbiodinolactone A is the first usual size macrolide and the first non-nitrogen-containing macrolide from dinoflagellate Symbiodinium sp. Symbiodinolactone A might be generated by the unexplained dinoflagellate polyketide biosynthetic machinery. 相似文献
33.
Yoshiaki Tsunawaki Mie Noguchi Mitsuhiro Kusaba Nobuhisa Ohigashi Masayuki Fujita Kazuo Imasaki Shin-ichiro Kuruma Kunioki Mima Sadao Nakai Chiyoe Yamanaka 《International Journal of Infrared and Millimeter Waves》1998,19(2):177-184
A hybrid planar wiggler with a period of 20 mm has been studied as the simplest one which gives the strong field including some higher harmonic components by selecting proper sizes of the ferromagnetic and the permanent magnet. Small gap length of the wiggler and small width of permendur satisfy these conditions to a certain degree.Gain analysis of FEL suggests that for high wiggler field of K>1 1.6, higher harmonic gains are improved primarily due to its strong field, and for low wiggler field of K< 1 1.6, they are mainly due to the modification of the wiggler field distribution. 相似文献
34.
Kajitani T Okoshi K Sakurai S Kumaki J Yashima E 《Journal of the American Chemical Society》2006,128(3):708-709
We report the unprecedented helix-sense controlled polymerization of enantiomerically pure phenyl isocyanides bearing an l- or d-alanine pendant with a long alkyl chain. The polymerization with an achiral nickel catalyst diastereoselectively proceeds, resulting in either a right- or left-handed helical polymer, whose helix-sense can be controlled by the polymerization solvent and temperature. Both the diastereomeric right- and left-handed helical polymers further self-assemble into lyotropic cholesteric liquid crystals with opposite twist-senses. Consequently, the macromolecular helicity and mesoscopic, supramolecular cholesteric twist can be controlled by the molecular chirality of the pendant of a single enantiomeric phenyl isocyanide through the polymerization under either kinetic or thermodynamic control assisted by hydrogen bonds. High-resolution atomic force microscopy revealed their helical conformations and enabled the determination of the helical sense. 相似文献
35.
Takemoto S Ogura S Yo H Hosokoshi Y Kamikawa K Matsuzaka H 《Inorganic chemistry》2006,45(13):4871-4873
A reaction between [CpFeCl]x and LiNHPh (1 equiv to Fe) produces a new paramagnetic Fe(II)-Fe(III) mu2-amido-mu2-imido complex [(CpFe)2(mu2-NHPh)(mu2-NPh)] (1), which, upon interaction with 2,2'-azobis(2,4-dimethylvaleronitrile), undergoes a net N-H hydrogen atom abstraction reaction to give a diamagnetic Fe(III)-Fe(III) mu2-imido dimer [CpFe(mu2-NPh)]2 (2). The molecular structures of 1 and 2 have been determined by single-crystal X-ray diffraction. 相似文献
36.
Shin-ichiro Takazawa 《Annals of the Institute of Statistical Mathematics》2012,64(3):615-632
We study the law of the iterated logarithm in the framework of game-theoretic probability of Shafer and Vovk. We investigate
hedges under which a game-theoretic version of the upper bound of the law of the iterated logarithm holds without any condition
on Reality’s moves in the unbounded forecasting game. We prove that in the unbounded forecasting game with an exponential
hedge, Skeptic can force the upper bound of the law of the iterated logarithm without conditions on Reality’s moves. We give
two examples such a hedge. For proving these results we derive exponential inequalities in the game-theoretic framework which
may be of independent interest. Finally, we give related results for measure-theoretic probability which improve the results
of Liu and Watbled (Stochastic Processes and their Applications 119:3101–3132, 2009). 相似文献
37.
Noguchi M Nakamura M Ohno A Tanaka T Kobayashi A Ishihara M Fujita M Tsuchida A Mizuno M Shoda S 《Chemical communications (Cambridge, England)》2012,48(45):5560-5562
An efficient chemo-enzymatic process for construction of the α-linked disaccharide unit (GlcNAcα1-4Gal) found in gastric mucin has been developed. The process consists of a one-step preparation of a novel triazine type glycosyl donor in water and the subsequent transglycosylation to a galactose derivative catalysed by α-N-acetylglucosaminidase. 相似文献
38.
S Kurimoto K Suzuki M Okasaka Y Kashiwada OK Kodzhimatov Y Takaishi 《Chemical & pharmaceutical bulletin》2012,60(7):913-919
Seven new sesquiterpene lactone glycosides (1-7) were isolated from the H2O-soluble fraction from the MeOH extract of the roots of Ferula varia. Their structures were elucidated by extensive spectroscopic analyses. The absolute configurations of compounds 1 and 2 were determined by modified Mosher's method. 相似文献
39.
Shin-ichiro Mizumoto 《Mathematische Annalen》1997,307(1):169-171
Math. Ann. 297, 581-625 (1993)
Received: 9 February 1996 / Revised version: 29 August 1996 相似文献
40.
Kouichi Akahane Naokatsu Yamamoto Shin-ichiro Gozu Akio Ueta Naoki Ohtani 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):81
InGaAsSb strain-reducing layers (SRLs) are applied to cover InAs quantum dots (QDs) grown on GaAs substrates. The compressive strain induced in InAs QDs from the GaAs is reduced due to the tensile strain induced by the InGaAsSb SRL, because the lattice constant of InGaAsSb is closer to InAs lattice constant than that of GaAs, resulting in a significant red shift of photoluminescence peaks of the InAs QDs. The emission wavelength from InAs QDs can be controlled by changing the Sb composition of the InGaAsSb SRL. The 1.5 μm band emissions were achieved in the sample with an InGaAsSb SRL whose Sb compositions were above 0.3. The calculation of the electron and the hole wave functions using the transfer matrix method indicates that the electron and the hole were localized around InAs QDs and InGaAsSb SRL. 相似文献