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Gang Chang Yasuhiko Shimotsuma Masaaki Sakakura Toshirou Yuasa Hidekazu Homma Munetaka Oyama Kiyotaka Miura Jiarong Qiu Peter G. Kazansky Kazuyuki Hirao 《Applied Surface Science》2008,254(16):4992-4998
Metal nanowires with electric conductive properties can be useful for optical polarization control medium and electro-conductive nanomaterial. We report on metallic Cu nanowires with a length of 1.0 μm and a diameter of 85 nm which were successfully photo-converted from commercial scale-like Cu particles, dispersed in a methanol solution, by using femtosecond laser irradiation. The growth mechanism of Cu nanowires under laser irradiation was suggested to be a nucleation growth process. 相似文献
144.
I Yuasa K Umetsu T Shotake T Ishida O Takenaka K Terao Y Kawamoto 《Electrophoresis》1990,11(10):840-845
Genetic variation of orosomucoid (ORM) in the genus Macaca was investigated. Plasma samples were subjected to isoelectric focusing in a pH range of 4-6.5, followed by immunoprinting with anti-human ORM antibodies. A total of 25 alleles were identified in 231 Asian macaques belonging to 13 species from 23 populations and 22 members belonging to a family of M. fascicularis. Family data presented evidence for a codominant mode of inheritance with multi-alleles at a single autosomal locus. A population study revealed enormous intra- and interspecies variations. The heterozygosity values varied from 0.855 in M. fascicularis (Malaysia) to 0.000 in M. radiata (India), M. silenus (India) and M. arctoides (Malaysia). 相似文献
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The bent conformation of a trisaccharide containing 2,4-diaminoxylopyranoside, in which both end sugars are presented in 1,3-diaxial orientation, is fixed by chelation of the diamino groups to Pt(II) and unfixed by a ligand exchange reaction with NaCN or thiourea giving its extended conformation. 相似文献
147.
Yuji Hayashi Takeshi Matsumoto Toshiaki Hyono Naomi Nishikawa Motokazu Uemura Mugio Nishizawa Masatoshi Togami Takeo Sakan 《Tetrahedron letters》1979,20(35):3311-3314
Nagilactone F was synthesized from (+)-podocarpic acid of the established structure. This work constitutes the first total synthesis of the biologically active norditerpenoid dilactones in plants. 相似文献
148.
The effects of alkyl chain length and of differences in the length of the two alkyl chains on the formation of a monolayer of chemically synthesized corynomycolic acid (2-alkyl-3-hydroxy fatty acid) at the air-water interface were examined. Hydrophobic interactions between the two alkyl chains are required for the formation of a condensed film, which is most stable when the total number of carbon atoms in the two alkyl chains is 25 or more and the difference in their lengths is one. Syn-isomers form condensed films but usually not anti-isomers. However, films may also be formed by the anti-isomer when the alkyl chain at the carboxy group (the 2-position) is longer than the alkyl chain at the hydroxy group (the 3-position). That is, the contribution of anti-isomers to condensed film formation depends on the polar carboxy group which has greater involvement in this formation. The extrapolated area for the condensed film of corynomycolic acid was 40 Å2 per molecule, thus confirming that both the carboxy and hydroxy groups are present on the water surface when a bipolar monolayer is formed. 相似文献
149.
We address multivariate integration and extrapolation techniques for the computation of Feynman loop integrals. Loop integrals are required for perturbation calculations in high energy physics, as they contribute corrections to the scattering amplitude and the cross section for the collision of elementary particles. We use iterated integration to calculate the multivariate integrals. The combined integration and extrapolation methods aim for an automatic calculation, where little or no analytic manipulation is required before the numeric approximation. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
150.
Electron injection is demonstrated to trigger electrocatalytic chain reactions capable of releasing a solvent molecule and forming a redox active guest molecule. One-electron reduction of a hydroxy anthrone derivative (AQH–CH2CN) results in the formation of an anthraquinone radical anion (AQ˙−) and acetonitrile (CH3CN). The resulting fragment of AQ˙− exhibits high stability under mild reducing conditions, and it has enough reducing power to reduce the reactant of AQH–CH2CN. Hence, subsequent electron transfer from AQ˙− to AQH–CH2CN yields the secondary AQ˙− and CH3CN, while the initial AQ˙− is subsequently oxidized to AQ. Overall, the reactants of AQH–CH2CN are completely converted into AQ and CH3CN in sustainable electrocatalytic chain reactions. These electrocatalytic chain reactions are mild and sustainable, successfully achieving catalytic electron-triggered charge-transfer (CT) complex formation. Reactant AQH–CH2CN is non-planar, making it unsuitable for CT interaction with an electron donor host compound (UHAnt2) bearing parallel anthracene tweezers. However, conversion of AQH–CH2CN to planar electron acceptor AQ by the electrocatalytic chain reactions turns on CT interaction, generating a host CT complex with UHAnt2 (AQ ⊂ UHAnt2). Therefore, sustainable electrocatalytic chain reactions can control CT interactions using only a catalytic amount of electrons, ultimately affording a one-electron switch associated with catalytic electron-triggered turn-on molecular recognition.The reactants of AQH–CH2CN are converted into AQ and CH3CN in sustainable electrocatalytic chain reactions, successfully achieving catalytic electron-triggered charge-transfer (CT) complex formation. 相似文献