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991.
992.
Shinji SATO 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2015,91(6):262-272
Characteristics of the 2011 Tohoku Tsunami have been revealed by collaborative tsunami surveys extensively performed under the coordination of the Joint Tsunami Survey Group. The complex behaviors of the mega-tsunami were characterized by the unprecedented scale and the low occurrence frequency. The limitation and the performance of tsunami countermeasures were described on the basis of tsunami surveys, laboratory experiments and numerical analyses. These findings contributed to the introduction of two-level tsunami hazards to establish a new strategy for tsunami disaster mitigation, combining structure-based flood protection designed by the Level-1 tsunami and non-structure-based damage reduction planned by the Level-2 tsunami. 相似文献
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Myeon‐Cheon Choi Jae‐Chul Hwang Chiwan Kim Shinji Ando Chang‐Sik Ha 《Journal of polymer science. Part A, Polymer chemistry》2010,48(8):1806-1814
Novel polynorbornene (PNB)‐polyimide (PI) copolymers were synthesized based on poly(N‐phenyl‐exo‐norbornene‐5,6‐dicarboximide) (PPhNI) and chlorinated PI (BPDA/TCDB). Polynorbornene copolymers (PNCs) with diverse compositions of anhydride were synthesized via ring opening metathesis polymerization (ROMP) of N‐phenyl‐exo‐norbornene‐5,6‐dicarboximide (PhNI) and exo‐7‐oxanorbornene‐5,6‐dicarboxylic anhydride(exo‐NA), followed by copolymerization through a reaction with aromatic dianhydride (3,3′,4,4′‐biphenyltetra‐carboxylic dianhydride, BPDA) and tetrachlorinated diamine (2,2′,5,5′‐tetrachlorobenzidine, TCDB). The copolymer (PNIC) films exhibited good optical transparency with a transmittance of around 70% at 400 nm and a good thermal stability with a glass transition temperature at 276–300 °C. These flexible films also resisted most organic solvents and chemicals, such as methanol, acetone, tetrahydrofuran, N‐methylpyrrolidone, ethyl acetate, hydrochloric acid, sodium hydroxide, and hydrogen peroxide, etc. Indium tin oxide (ITO) coated thin films were prepared at various substrate deposition temperatures with a radio frequency (r.f.) planar magnetron sputtering system. The ITO thin films that were deposited onto the PNIC copolymer substrates had good electrical and optical properties. An organic light‐emitting device (OLED) was fabricated using the PNIC copolymer substrate with a structure of PNIC08/ ITO (anode)/hole‐transporting layer (HTL)/emitting & electron‐transporting layer (EM&ETL)/aluminum (cathode). The flexible OLED fabricated on the ITO‐grown PNIC substrate exhibited a performance that was comparable to corresponding ITO‐grown glass substrates. Therefore, the ITO‐grown PNIC substrate could possibly be a promising candidate as a substrate for flexible displays. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1806–1814, 2010 相似文献
994.
Dr. Tetsuo Iwanaga Kazuaki Miyamoto Dr. Kazukuni Tahara Koji Inukai Satoshi Okuhata Prof. Dr. Yoshito Tobe Prof. Dr. Shinji Toyota 《化学:亚洲杂志》2012,7(5):935-943
We have synthesized anthracene–acetylene oligomers, which contained one 10-substituted anthracene unit and one anthraquinone unit, by cyclization with Sonogashira coupling. X-ray analysis revealed an almost-planar framework and significant out-of-plane deformation around the inner carbonyl moiety because of steric hindrance. These compounds underwent self-association in solution and their association constants for monomer–dimer exchange were determined by variable-concentration 1H NMR measurements in CDCl3: 8 mol−1 L (10-substituent: isopropyl), <5 mol−1 L (methoxy), and 19 mol−1 L (octyloxy). These results were discussed on the basis of spectroscopic and molecular-orbital analysis. A linear molecular assembly of the octyloxy compound at a liquid/graphite interface was observed by STM measurements. 相似文献
995.
Shinji Higashijima Hidetoshi MiuraTomoki Fujita Yasuhiro KubotaKazumasa Funabiki Tsukasa YoshidaMasaki Matsui 《Tetrahedron》2011,67(34):6289-6293
New indoline dye (DN319) having strong electron-withdrawing dicyanovinylidene moiety and octyl group in the terminal rhodanine ring gave higher efficiency than D205, which was known as an excellent organic dye sensitizer. This result is attributed to the bathochromic shift in the UV-vis absorption band and positive shift in the Eox level of DN319. 相似文献
996.
Tatsuo Nishitani 《偏微分方程通讯》2013,38(12):1273-1296
997.
Shinji Yamada Akinori Takasu Kazuhiko Kawamura 《Journal of polymer science. Part A, Polymer chemistry》2013,51(17):3732-3739
We examined the ring‐opening polymerization of ε‐caprolactone in toluene between 50 and 70 °C, and catalyzed by some Lewis and Brønsted acids to investigate the effects of microwave versus conventional heating on the kinetics and activation thermodynamics of the reaction. The polymerizations proceeded more rapidly when microwave heating, instead of conventional heating, was used to control the temperature. The number‐average molecular weight (Mn) of the polymer could be controlled even when microwave heating was used. To identify which thermodynamic activation constants were responsible for the accelerated polymerizations, we performed the reaction at different temperatures to obtain data for the Arrhenius and Eyring equations. Although the values for the activation energies and the activation enthalpies were larger when microwave heating rather than conventional heating was used, the frequency factors and the activation entropies (ΔS?) over compensated for the less favorable activation energies and enthalpies. The more favorable ΔG? found for the microwave‐assisted polymerizations mainly reflect the larger ΔS? values, and the rate accelerations appear to be a consequence of differently arranged intermediates and/or transition states. © 2013 Wiley Periodicals, Inc. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3732–3739 相似文献
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