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31.
Hexagonal-pillar shaped pure Fe single crystal whiskers with six {1 1 0} side planes were obtained by means of chemical vapor deposition. Atomically resolved scanning tunneling microscopy images obtained on the {1 1 0} surface showed a quasi-hexagonal atomic array with mesoscopic-range periodic height modulation of about 1/3 of an atomic step. This height modulation was found to be a result of an interference between the quasi-hexagonal top-layer and the sub-surface bcc-Fe{1 1 0} layer. Unit vectors of the mesoscopic-range modulation turned out to be expressed as , where and are the primitive vectors of the two-dimensional atomic array in the top-layer and those in the sub-surface layer, respectively. The two-dimensional density of atoms in the top-layer is slightly higher by 0.46% than that in the sub-surface layer. 相似文献
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The synthesis of a series of hydrosilylboronates via the selective iridium- or nickel-catalyzed monoborylation of dihydrosilane Si–H bonds is described. The synthesized silylboronates, which bear a single Si–H bond, can be used as novel silicon nucleophiles in the presence of transition-metal catalysts or bases. The first 29Si{1H} NMR spectroscopic evidence for the formation of (t-Bu)2HSiLi, generated by the reaction of (t-Bu)2HSi–B(pin) with MeLi, is reported as the first example of a dialkylhydorosilyl lithium species.Monoborylation of a dihydrosilane Si–H bond can be achieved in the presence of iridium- or nickel-based catalysts, yielding novel hydrosilylboronates that bear a hydrogen atom at the silicon center. 相似文献
34.
Asakura H Teramura K Shishido T Tanaka T Yan N Xiao C Yao S Kou Y 《Physical chemistry chemical physics : PCCP》2012,14(9):2983-2990
A combination of in situ time-resolved DXAFS and ICP-MS techniques reveals that the formation process of Rh nanoparticles (NPs) from rhodium trichloride trihydrate (RhCl(3)·3H(2)O) in ethylene glycol with polyvinylpyrrolidone (PVP) at elevated temperature is a first-order reaction, which indicates that uniform size Rh NPs appear consecutively and these Rh NPs do not aggregate with each other. 相似文献
35.
S Tonegawa K Hashimoto K Ikada YH Lin H Shishido Y Haga TD Matsuda E Yamamoto Y Onuki H Ikeda Y Matsuda T Shibauchi 《Physical review letters》2012,109(3):036401
We report the first observation of cyclotron resonance in the hidden-order phase of ultraclean URu_{2}Si_{2} crystals, which allows the full determination of angle-dependent electron-mass structure of the main Fermi-surface sheets. We find an anomalous splitting of the sharpest resonance line under in-plane magnetic-field rotation. This is most naturally explained by the domain formation, which breaks the fourfold rotational symmetry of the underlying tetragonal lattice. The results reveal the emergence of an in-plane mass anisotropy with hot spots along the [110] direction, which can account for the anisotropic in-plane magnetic susceptibility reported recently. This is consistent with the "nematic" Fermi liquid state, in which itinerant electrons have unidirectional correlations. 相似文献
36.
The magic number behavior of ((CH(3))(3)N)(n)-H(+)-H(2)O clusters at n = 3 is investigated by applying infrared spectroscopy to the clusters of n = 1-3. Structures of these clusters are determined in conjunction with density functional theory calculations. Dissociation channels upon infrared excitation are also measured, and their correlation with the cluster structures is examined. It is demonstrated that the magic number cluster has a closed-shell structure, in which the water moiety is surrounded by three (CH(3))(3)N molecules. The ion core (protonated site) of the clusters is found to be (CH(3))(3)NH(+) for n = 1-3, but coexistence of an isomer of the H(3)O(+) ion core cannot be ruled out for n = 3. Large rearrangement of the cluster structures of n = 2 and 3 before dissociation, which has been suggested in the mass spectrometric studies, is confirmed on the basis of the structure determination by infrared spectroscopy. 相似文献
37.
Haifeng Yu Atsushi Shishido Tomokazu Iyoda Tomiki Ikeda 《Macromolecular rapid communications》2007,28(8):927-931
Novel wormlike nanostructures were self‐assembled in bulk films of a well defined diblock copolymer with azobenzene moieties, which was prepared by atom transfer radical polymerization (ATRP). For comparison, a homopolymer with almost the same repeat units of azobenzene as those in the copolymer was also prepared. They both had well defined structures and exhibited a smectic liquid crystalline phase. Upon annealing the copolymer films, poly(methyl methacrylate) formed a matrix with excellent optical properties, and the azobenzene segment in the minority phase self‐assembled into a wormlike mesogenic domain in the bulk films. Such block copolymer films exhibited stability and transparency by eliminating the scattering of visible light, indicating their potential application as photoresponsive functional materials. Although wormlike morphologies have been obtained in micelles from block copolymer solutions, to the best of our knowledge, such wormlike nanostructures have never been explored in bulk films.
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