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Masahiro Ishino Kaoru Kinoshita Kunio Takahashi Takashi Sugita Motoo Shiro Kimiko Hasegawa Kiyotaka Koyama 《Tetrahedron》2012,68(41):8572-8576
Three novel diterpenes, phomactins K–M (1–3), were isolated from the cultures of an unidentified marine-derived fungus. The structures of 1–3 were elucidated from spectroscopic data (NMR, MS, IR), and the absolute configurations of 1, 2, and the relative configuration of 3 were determined by X-ray diffraction analysis. 相似文献
84.
Tohru TakeiTakumi Ohki Yosuke HaradaNaoto Kumagai Hiroki FukumotoTake-aki Koizumi Akihiro MaedaTakahiro Kojima Yoshihisa SeiKohei Shiramizu Masahiro AbeMasashi Oota Takakazu Yamamoto 《Tetrahedron letters》2012,53(44):5907-5910
Dibromopyridines or dibromopyridone with -(CH2)m-SO3Na group(s) has been prepared via the reactions of the corresponding dibromopyridines with -OH and -NH2 groups with sultone. These compounds were converted into polymers with the -(CH2)m-SO3H groups via organometallic polycondensation. The polymer showed proton conducting properties and high stability toward oxidation. 相似文献
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Dr. Ding‐Bang Xiong Dr. Norihiko L. Okamoto Dr. Takeshi Waki Dr. Yufeng Zhao Dr. Kyosuke Kishida Prof. Dr. Haruyuki Inui 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(9):2536-2542
Heusler phases, including the full‐ and half‐Heusler families, represent an outstanding class of multifunctional materials on account of their great tunability in compositions, valence electron counts (VEC), and properties. Here we demonstrate a systematic design of a series of new compounds with a 2×2×2 superstructure of the half‐Heusler unit cell in X–Y–Z (X=Fe, Ru, Co, Rh, Ir; Y=Zn, Mn; Z=Sn, Sb) systems. Their structures were solved by using both powder and single‐crystal X‐ray diffraction, and also directly observed by using high‐angle annular dark‐field imaging in a scanning transmission electron microscope (HAADF‐STEM). The VEC values of these new compounds span a wide and continuous range comparable to those for the full‐ and half‐Heusler families, thereby implying tunability in compositions and physical properties in the superstructure. In fact, we observed abnormal electrical properties and a ferromagnetic semiconductor‐like behavior with a high and tunable Curie temperature in these superstructures. 相似文献
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Kenji Kinashi Yuki Kambe Masahiro Misaki Yasuko Koshiba Kenji Ishida Yasukiyo Ueda 《Journal of polymer science. Part A, Polymer chemistry》2012,50(24):5107-5114
Three types of bi‐functionalized copolymers ( P1FAz , P2FAz , and P3FAz ) with different numbers of fluorene units and an azobenzene unit were synthesized and characterized using UV–vis and polarized absorption spectroanalysis. The trans‐cis photoisomerization was conformed under 400 nm light irradiation for all copolymers in chloroform. However, in the film state, only the trans‐cis photoisomerization occurred by mono‐fluorene attached copolymer poly[(9,9‐di‐n‐octylfluorenyl‐2,7‐diyl)‐alt‐4,4′‐azobenzene)] ( P1FAz ). Photo‐induced alignment was achieved using the P1FAz film after irradiation with linear polarized 400 nm light and subsequent annealing at 60 °C. Surface orientation of a spin‐coating film of poly(9,9‐didodecylfluorene) ( F12 ) was achieved using the photo‐induced alignment layer of the P1FAz film after annealing at 90 °C. The photo‐induced alignment layer of P1FAz has potential application to the surface orientation technique for appropriate polymers, which will be useful for the fabrication of optoelectronics devices. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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Annealing polyethylene terephthalate (PET)/polycarbonate (PC) blends enhance the transesterification reaction and increase the amount of copolymer at the interface of both polymers. The copolymer enhances the compatibility of PET with PC, because it contains both PET and PC blocks, which causes the interface between PET and PC to become fuzzy. When the PET/PC undergoes batch physical foaming with CO2, the copolymer significantly changes the resulting cell morphology, that is, the annealing time. Before annealing or in the absence of the copolymer, bubble nucleation occurs and dominates growth at the interface. When the PET/PC blends are annealed, the interface impedes bubble nucleation and growth. The polymer is stretched at the interface by bubble growth, forming fibril‐like structures connecting two polymer domains at the interface. Increased annealing time causes the interface to become more homogeneous and makes heterogeneous bubble nucleation difficult. At higher copolymer concentrations, the interface of PET and PC becomes fuzzy and the cell morphology becomes like those of foamed homogeneous polymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献