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61.
Anna V. Klassen Makoto Matsukura Osamu Nakamura Vladimir V. Kochurikhin Mikhail A. Ivanov Galina Yu. Orlova Akio Miyamoto Yasunori Furukawa 《Journal of Crystal Growth》2008,310(11):2895-2898
The applicability of the edge-defined film-fed growth (EFG) technique for YbxY(1−x)VO4 (x=0.05, 0.1 and 1) was approved by successful growth of crystals up to 80 mm in length as the thin plates. Low-angle grain boundaries and the crystal coloration as main defects were found. Optimal seed orientation was suggested on the strength of vanadate crystal plate morphology. Optical properties, chemical composition and the crystalline quality were investigated. 相似文献
62.
Anisotropic optical properties and nanostructures of thin films prepared by oblique co-deposition of Ag and SiO2 were studied. At low concentrations of Ag, a columnar structure grew towards the direction of the incident SiO2 vapor and small Ag particles were embedded in that structure. An inhomogeneous distribution of Ag was observed in cases where the Ag was deposited from the opposite side of the surface normal to the direction of the incident SiO2 vapor. This inhomogeneous distribution of Ag particles gives rise to optical anisotropy, i.e., the optical transmittance of p-polarized light varies drastically depending on the angle of incidence, while that of s-polarized light remains unchanged. A possible application of the anisotropic optical absorption properties of Ag---SiO2 hybrid films is in the manufactur of an inorganic thin film polarizer. 相似文献
63.
Shigeyasu Tanaka Yoshio Honda Norifumi Kameshiro Ryuta Iwasaki Nobuhiko Sawaki Takayoshi Tanji Mikio Ichihashi 《Journal of Crystal Growth》2004,260(3-4):360-365
We have investigated the morphology of the high-temperature-grown AlN nucleation layer and its role in the early stage of GaN growth, by means of transmission electron microscopy. The nitride was selectively grown on a 7-degree off-oriented (0 0 1) patterned Si substrate by metalorganic vapor phase epitaxy. AlN was deposited on the inclined unmasked (1 1 1) facet in the form of islands. The size of the islands varied along the slope, which is attributable to the diffusion of the growth species in the vapor phase. The GaN nucleation occurred at the region where rounded AlN islands formed densely. The threading dislocations were observed to generate in the GaN nucleated region. 相似文献
64.
65.
A non‐volatile, bistable, and rewritable organic memory device was successfully fabricated with the layers of poly(2,2,6,6‐tetramethylpiperidine‐1‐oxyl methacrylate) (PTMA) and poly(methyl methacrylate) (PMMA) containing silver salt. The PTMA layer was employed as a p‐dopable material, while the silver salt‐dispersed PMMA layer acted as an n‐dopable material. The ON–OFF ratio between low‐conductivity and high‐conductivity states amounted to more than four orders of magnitude, and the retention time was longer than 103 sec. The device was characterized by excellent rewritability. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
66.
Annulation of Alkynyl Aryl Ethers with Allyl Pivalates To Give 2,3‐Bismethylenechromanes through Double C−H Bond Cleavage
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Dr. Yasunori Minami Megumi Sakai Tomohiro Anami Prof. Dr. Tamejiro Hiyama 《Angewandte Chemie (International ed. in English)》2016,55(30):8701-8705
The treatment of silylethynyloxyarenes with allylic pivalates in the presence of a palladium catalyst led to efficient C?H bond cleavage in both substrates and a novel annulation reaction to give 2,3‐bismethylenechromanes. When ortho‐allylated silylethynyloxybenzenes were used as the substrates, the same products were obtained. This result shows that site‐selective intramolecular hydrovinylation is involved in the annulation reaction. The synthetic utility of the products was demonstrated by the construction of condensed polycycles. 相似文献
67.
[reaction: see text] Ethyl 1-thio-2,3,4,6-tetrakis-O-triisopropylsilyl-beta-d-glucopyranoside, ethyl 6-O-benzyl-1-thio-2,3,4-tris-O-triisopropylsilyl-beta-d-glucopyranoside, and ethyl 6-O-pivaloyl-1-thio-2,3,4-tris-O-triisopropylsilyl-beta-d-glucopyranoside induced highly beta-selective O-glucosidations. Among them, the 6-O-pivaloylated substrate provided the best selectivity up to alpha/beta = 3:97 with cyclohexylmethanol, and the substrate was used for glucosidations with secondary and tertiary alcohols in a highly beta-selective manner. The selectivity would be caused by the twist-boat conformation of the pyranose; this is the first beta-selective O-glucosidation based on conformational control of the pyranose ring. 相似文献
68.
Yasunori Igasaki Fanghong Li Narihiro Yoshida Haruyoshi Toyoda Takashi Inoue Naohisa Mukohzaka Yuji Kobayashi Tsutomu Hara 《Optical Review》1999,6(4):339-344
To realize a high efficiency electrically addressable phase-only modulator, we have coupled a liquid crystal display (LCD) to an optically addressed parallel-aligned nematic liquid crystal spatial light modulator (PAL-SLM) with a set of lenses. Phase modulation exceeding 3ϖ at 532 nm wavelength was obtained. We obtained linear transfer characteristics for phase modulation at various desired phase levels after calibration and adjustment of the transfer characteristics of the PAL-SLM and the LCD. Diffraction efficiency of 40% for binary phase grating and of 90% for 8-level blazed phase grating, which were very close to the simulation values, were observed. The power loss of the readout light was caused when passed through a half mirror, therefore, we examined a setup using an oblique readout light at the modulator. Very high diffraction efficiency was obtained from the setup by optimizing the polarization direction and optical path for this light, and the orientation of liquid crystals. Since the modulator can perform at better than 90% diffraction efficiency and at nearly 100% reflectivity, various high efficiency systems utilizing such modulators are expected. 相似文献
69.
Yasunori Fujikoshi Takashi Kanda Megu Ohtaki 《Annals of the Institute of Statistical Mathematics》1999,51(4):707-721
This paper deals with some inferential problems under an extended growth curve model with several hierarchical within-individuals design matrices. The model includes the one whose mean structure consists of polynomial growth curves with different degrees. First we consider the case when the covariance matrix is unknown positive definite. We derive a LR test for examining the hierarchical structure for within individuals design matrices and a model selection criterion. Next we consider the case when a random coefficients covariance structure is assumed, under certain assumption of between-individual design matrices. Similar inferential problems are also considered. The dental measurement data (see, e.g., Potthoff and Roy (1964, Biometrika, 51, 313-326)) is reexamined, based on extended growth curve models. 相似文献