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131.
The regiospecific synthesis of alkylated lumazines is achieved by hetero Diels-Alder addition between an oxadiazinone 2 and enamine. The reactions proceed stepwise by cycloaddition, decarboxylation and deamination to produce the 6-alkylated lumazines. 相似文献
132.
H. Ohsaki K. Miura A. Imai M. Tada M. A. Aegerter 《Journal of Sol-Gel Science and Technology》1994,2(1-3):245-249
The structure of SiO2 gel-films prepared from acid and basic TEOS solutions is analyzed by high energy transmission electron diffraction method. The Si-O bond length of gel-films is 1.58 to 1.60 Å, which is shorter than that of vitreous silica (1.61 Å) but similar to that of 80 Å thick evaporated a-SiO2 film. An atomic pair peak with 0.81 Å distance exists on the reduced radial distribution functions of the gel-films, which is believed to be O-H, but being smaller than that of H2O (0.969 Å). 相似文献
133.
Ryohei Yasukuni Jean-Alexis Spitz Rachel Meallet-Renault Takuji Tada Tsuyoshi Asahi Yuji Hiraki Hiroshi Masuhara 《Applied Surface Science》2007,253(15):6416-6419
Three-dimensional dissection of a single actin stress fiber in a living cell was performed based on multi-photon absorption of a focused femtosecond laser pulse. The realignment process of an actin stress fiber was investigated after its direct cutting by a single-shot femtosecond laser pulse irradiation by high-speed transmission and fluorescence imaging methods. It was confirmed that mechanical force led by the femtosecond laser cutting propagates to entire cell through the cytockelton in a 100 μs time scale. The cut actin stress fiber was realigned in the time scale of a few tens of minutes. The dynamic analysis of the realignment induced by single-shot femtosecond laser gives new information on cell activity. 相似文献
134.
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
135.
Y. Hamasaki T. Miyamoto Y. Kuhara M. Katoh K. Tada S. Takeuchi T. Nakahara 《Fiber and Integrated Optics》1981,3(4):383-389
An optical fiber sensor for measuring high electric field intensity and voltage, which utilizes the electro-optic effect of bismuth silicone oxide single crystal, has been developed successfully, and the fundamental characteristics have been evaluated. The electric field intensity distribution inside the coaxial electrodes has been measured with this sensor. The measured results are in agreement with the theoretical values. 相似文献
136.
137.
138.
Nakanishi S Fukami K Tada T Nakato Y 《Journal of the American Chemical Society》2004,126(31):9556-9557
Strikingly well-ordered Sn latticeworks, standing perpendicular to the substrate, are formed spontaneously in oscillatory electrodeposition. Cooperation of various processes, such as needle formation by autocatalytic crystal growth, cuboid formation under a reaction-limited condition, and autocatalytic oxidation at closest-packed surfaces, enabled the self-organization of the latticeworks. The mechanism is generally applicable to deposition of other metals such as Zn, Pb, and Cu. The present work has opened a promising, unique field toward the formation of highly ordered 3-D micro- or nanostructures at solid surfaces. 相似文献
139.
[reaction: see text]. Novel anodic intermolecular carbon-carbon bond formation has been accomplished by the oxidative carbon-sulfur bond fission of benzylic dithioacetals to give a wide variety of aromatic compounds. The substitution reaction successfully took place by the selective anodic oxidation of a sulfur atom of a dithioacetal. Stepwise double-substitution reactions were also achieved by the regulation of oxidation potential. 相似文献
140.
Tada K Haruyama J Yang HX Chshiev M Matsui T Fukuyama H 《Physical review letters》2011,107(21):217203
Theoretically, the so-called zigzag edge of graphenes provides localized electrons due to the presence of flat energy bands near the Fermi level. Spin interaction makes the localized spins strongly polarized, yielding ferromagnetism. However, in most experimental studies, ferromagnetism has been observed in uncontrollable and complicated carbon-based systems. Here, we fabricate graphenes with honeycomblike arrays of hexagonal nanopores, which have a large ensemble of hydrogen-terminated and low-defect pore edges that are prepared by a nonlithographic method (nanoporous alumina templates). We observe large-magnitude ferromagnetism derived from electron spins localizing at the zigzag nanopore edges. This promises to be a realization of graphene magnets and novel spintronic devices. 相似文献