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991.
Maeda K Matsushita Y Ezaka M Yashima E 《Chemical communications (Cambridge, England)》2005,(33):4152-4154
The macromolecular helicity of charged poly(phenylacetylene)s induced by small chiral guests in water can be retained by the alternative deposition of achiral polyelectrolytes with opposite charges, resulting in optically active multilayer thin films with a macromolecular helicity memory. 相似文献
992.
Hideki Sugimoto Kazunori Nunome Kazuki Daimatsu Eiji Nakanishi Katsuhiro Inomata 《Colloid and polymer science》2010,288(10-11):1131-1138
The aim of this study was to prepare transparent nanohybrid films with low coefficient of thermal expansion (low CTE), which consist of acryl resin and nanosized clay. The hybrid films with different clay contents were prepared by UV curing of tricyclodecane dimethanol diacrylate (TCDDMDA) including nanosized clay. All obtained films were transparent similar to pure poly(TCDDMDA). In addition, the film containing 40 wt.% of clay showed a low CTE of 10 ppm/K in 150–200 °C, which is similar to that of inorganic materials such as glass. The significant property improvement is related to shape effect and orientation of clay in polymer matrix. Wide-angle X-ray diffraction measurement was carried out to investigate orientation of nanosized clay in polymer matrix. From this measurement, it was confirmed that the clay platelets were oriented parallel with film surface with increasing clay content, and orientation coefficient of the clay in polymer matrix reached to f?=?0.65 for the hybrid film containing 40 wt.% of clay. Though, in comparison with the matrix, the flexibility of the hybrid film evaluated by the wind roll test with steel bar was lowered by increase of clay content, the hybrid film containing 40 wt.% of clay could be rewound with steel bar 10 mm across, and its flexibility was retained. 相似文献
993.
Solid solutions BiMn1-xMxO3 with M=Al, Sc, Cr, Fe, and Ga and 0相似文献
994.
Keisho Okura Tsuyoshi Teranishi Yuto Yoshida Prof. Dr. Eiji Shirakawa 《Angewandte Chemie (International ed. in English)》2018,57(24):7186-7190
Arylboroxines in combination with zinc chloride and potassium tert‐butoxide were found to undergo the electron‐catalyzed cross‐coupling with aryl iodides to give the corresponding biaryls without the aid of transition‐metal catalysis. 相似文献
995.
Iida M Baba C Inoue M Yoshida H Taguchi E Furusho H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(16):5047-5056
We have prepared novel ionic liquids of bis(N-2-ethylhexylethylenediamine)silver(I) nitrate ([Ag(eth-hex-en)(2)]NO(3) and bis(N-hexylethylenediamine)silver(I) hexafluorophosphate ([Ag(hex-en)(2)]PF(6)), which have transition points at -54 and -6 degrees C, respectively. Below these transition temperatures, both the silver complexes assume amorphous states, in which the extent of the vitrification is larger for the eth-hex-en complex than for the hex-en complex. The diffusion coefficients of both the complex cations, measured between 30 (or 35) and 70 degrees C, are largely dependent on temperature; the dependence is particularly large in the case of the eth-hex-en complex cation below 40 degrees C. Small-angle X-ray scattering studies showed that the bilayer structure of the metal complex is formed in the liquid state for both the silver complexes. A direct observation of the yellowish [Ag(eth-hex-en)(2)]NO(3) liquid by transmission electron microscopy (TEM) indicates the presence of nanostructures, as a microemulsion, of less than 5 nm. Such structures were not clearly observed in the [Ag(hex-en)(2)]PF(6) liquid. Although the [Ag(eth-hex-en)(2)]NO(3) liquid is sparingly soluble in bulk water, it readily incorporates a small amount of water up to [water]/[metal complex] = 7:1. Homogeneous and uniformly sized silver(0) nanoparticles in water were created by the reduction of the [Ag(eth-hex-en)(2)]NO(3) liquid with aqueous NaBH(4), whereas silver(0) nanoparticles were not formed from the [Ag(hex-en)(2)]PF(6) liquid in the same way. 相似文献
996.
Core-shell-structured La2O3:Eu3+-La2Sn2O7 nanoparticles were fabricated through SnO2-coating of LaOF:Eu3+ in an aqueous solution and subsequent heat treatments at a higher temperature. The nanoparticles exhibited high chemical stability under an ambient atmosphere and intense red photoluminescence upon irradiation with ultraviolet light. 相似文献
997.
Yasuhiro Kohsaka Eiji Yamaguchi Tatsuki Kitayama 《Journal of polymer science. Part A, Polymer chemistry》2014,52(19):2806-2814
Anionic polymerizations of acrylates possessing 1‐pyrenyl (Py1), 1‐naphthyl (Np1), 2‐naphthyl (Np2), and 2‐fluorenyl (Fl2) groups as α‐substituents were investigated as well as the properties of the obtained polymers. Py1 and Np1 did not undergo polymerization, whereas Np2 and Fl2, annulated α‐phenylacrylates at 3,4‐position of the phenyl group, afforded homo‐oligomers and alternating copolymers with methyl methacrylate (MMA). The oligomer of Fl2 [oligo(Fl2)] exhibited strong excimer emission in diluted solution. In contrast, dominant monomer emission was observed for the alternating copolymer with MMA [poly(Fl2‐co‐MMA)]. In the alternating copolymer, MMA units could function as spacers preventing the association of pendant fluorene moieties to suppress the excimer formation. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2806–2814 相似文献
998.
Mi-Seon Choi Takuya Yamamoto Tomoyuki Kakeshita Eiji Taguchi Hirotaro Mori 《哲学杂志》2013,93(16):2449-2460
A Ti–44Ni–6Fe (at. %) alloy was recently reported to exhibit a second order-like incommensurate–commensurate transformation. Whether or not the commensurate (C) phase and the R-phase in Ti–Ni alloys are the same phase has now been investigated. Transformation behaviour was examined in a series of Ti–(50 ? x)Ni–xFe (at. %) alloys with x = 2.0, 4.0, 5.0, 5.5, 5.7, 6.0. Transformation temperature, entropy change and the transformation strain decrease continuously as x increases up to x = 5.7, where the product phase is apparently the R-phase. However, there is an obvious discontinuity in these values between x = 5.7 and x = 6.0. In addition, electron diffraction experiments have revealed that the intensity of satellite reflections of the C-phase is obviously weaker than that of the R-phase. These results strongly suggest that the C-phase is different from the R-phase. 相似文献
999.
1000.
Daichi Tanaka Yudai Numata Kazuya Nakagawa Takayoshi Kobayashi Eiji Tokunaga 《Optical Review》2016,23(3):373-381
Cross-shaped excimer (self-trapped exciton) luminescence from α- and β-perylene single crystals of 50–100 μm was found when they were excited at the center of the crystals with a continuous-wave (cw) laser resonant with the exciton absorption. The cross shape is formed by the two lines which intersect at the excited position and are perpendicular to the sides of the crystals of parallelogram shape. Luminescence is emitted from the excited spot and 4 side edges in the cross shape. The most striking feature is that the luminescence intensity at the edges was as high as or higher than at the excited spot. The possibility of the exciton propagation or the waveguide effect is rejected both experimentally and theoretically. This phenomenon can be reasonably explained only when the radiative transition probability of excimers is significantly enhanced at the crystals side edges than at the center due to the lower symmetry. 相似文献