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Jun Komiyama Kenichi Eriguchi Yoshihisa Abe Shunichi Suzuki Hideo Nakanishi Takayoshi Yamane Hisashi Murakami Akinori Koukitu 《Journal of Crystal Growth》2008,310(1):96-100
The hydride vapor phase epitaxy (HVPE) of {0 0 0 1} AlN films on {1 1 1} Si substrates covered with epitaxial {1 1 1} cubic SiC (3C-SiC intermediate layers) was carried out. 3C-SiC intermediate layers are essential to obtain high-quality AlN films on Si substrates, because specular AlN films are obtained with 3C-SiC intermediate layers, whereas rough AlN films are obtained without 3C-SiC intermediate layers. We determined the polarities of AlN films and the underlying 3C-SiC intermediate layers by convergent beam electron diffraction (CBED) using transmission electron microscopy. For the first time, the polarities of the AlN films and the 3C-SiC intermediate layers were determined as Al and Si polarities, respectively. The AlN films were hardly etched by aqueous KOH solution, thereby indicating Al polarity. This supports the results obtained by CBED. The result is also consistent with electrostatic arguments. An interfacial structure was proposed. The 3C-SiC intermediate layers are promising for the HVPE of AlN films on Si substrates. 相似文献
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Hideo Togo Yoichiro Hoshina Masataka Yokoyama 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):449-450
Sulfonamides of primary amine bearing an aromatic ring at γ-position were treated with (diacetoxyiodo)arene and iodine under irradiation conditions with a tungsten lamp to give the corresponding 1,2,3,4-tetrahydroquinoline derivatives in moderate to good yields. 相似文献
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Atsuo Iida Corresponding author Yumiko Takahashi Yoichi Takanishi Michi Nakata Ken Ishikawa Hideo Takezoe 《Liquid crystals》2013,40(6):717-726
The local layer structure of surface stabilized electroclinic liquid crystals has been analysed by time‐resolved synchrotron X‐ray microdiffraction. At a low applied electric field, the initial bookshelf structure starts to respond above a threshold voltage. With a low to medium applied field of triangular form, the layer structure transforms reversibly between the bookshelf (low field) and the compound chevron (high field), in which the vertical and horizontal chevrons alternate along the layer. When the horizontal chevron component appears, a stripe texture can be seen in an optical micrograph. With increasing field, the horizontal chevron becomes a dominant structure while the vertical chevron still remains. The layer spacing changes in correlation with the chevron angle during the field application. At high field, surface molecules partly rearrange, resulting in alignment deterioration at the interface. The layer response time for an a.c. square wave field is of the order of a few µs to ten µs, which is close to the optical response. The appearance of the compound chevron is discussed in conjunction with the anchoring effect. 相似文献
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Hideaki MIYATA Hideo ORIHARA Yohei SATO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2014,90(8):278-300
Research works undertaken in the first author’s laboratory at the University of Tokyo over the past 30 years are highlighted. Finding of the occurrence of nonlinear waves (named Free-Surface Shock Waves) in the vicinity of a ship advancing at constant speed provided the start-line for the progress of innovative technologies in the ship hull-form design. Based on these findings, a multitude of the Computational Fluid Dynamic (CFD) techniques have been developed over this period, and are highlighted in this paper. The TUMMAC code has been developed for wave problems, based on a rectangular grid system, while the WISDAM code treats both wave and viscous flow problems in the framework of a boundary-fitted grid system. These two techniques are able to cope with almost all fluid dynamical problems relating to ships, including the resistance, ship’s motion and ride-comfort issues. Consequently, the two codes have contributed significantly to the progress in the technology of ship design, and now form an integral part of the ship-designing process. 相似文献
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Inside Cover: Molecularly Designed Nanoparticles by Dispersion of Self‐Assembled Organosiloxane‐Based Mesophases (Angew. Chem. Int. Ed. 35/2014) 下载免费PDF全文