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941.
942.
Tomohiro Yasuda Yukiko Okimura Arata Oishi Hisashi Kokubo Masayoshi Watanabe 《Journal of polymer science. Part A, Polymer chemistry》2013,51(10):2233-2242
The alternating copolymerization of phenylmaleimide (PMI) with a pendant sulfonamide acid group (sa‐PMI) and n‐butyl vinyl ether (BVE) as the aliphatic vinyl monomer afforded proton‐conducting polymer electrolytes—sa‐PMI‐BVEs—and their properties were compared with those of sa‐PMI‐STs that were synthesized from sa‐PMI and styrene. The ion exchange capacities (IECs) can be easily controlled by partly replacing sa‐PMI with unsubstituted PMI. sa‐PMI‐BVE is more flexible than sa‐PMI‐ST, and therefore, forms thin membranes even at high IECs, while sa‐PMI‐ST membranes are rigid and brittle. However, sa‐PMI‐BVE exhibits rather low thermal and oxidative stability. To realize polymer electrolyte membranes with reliable mechanical strength and a high IEC, gel‐filled membranes were prepared by polymerization in the presence of a small amount of a crosslinker, divinylbenzene, in porous polytetrafluoroethylene membranes. By using the gel‐filled membrane, H2/O2 fuel cells could be operated at 80 °C with reasonable performance. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013 相似文献
943.
944.
The first enantioselective synthesis of rumphellaone A, a cytotoxic 4,5-seco-caryophyllane derivative incorporating a γ-lactone ring as its structural feature, has been achieved by using base-induced intramolecular cyclization of an epoxy nitrile intermediate to install its cyclobutane skeleton as well as three contiguous stereocenters as the key transformation. 相似文献
945.
We report on the refractive index modification (Δn) and its cross sectional profile of the created lines inside the different types of optical glasses, containing BaO, TiO2, or La2O3 as a metal oxide. The lines were fabricated by scanning a stage and focusing the femtosecond laser pulses, 800 nm wavelength, a 250 kHz repetition rate and 200 fs pulse duration, from the Ti:sapphire regenerative amplifier system. The Δn measurements were performed with the qualitative phase microscopy technique. As a result, it was found that the Δn and its sign are different depending on glass types. For example, in the glasses containing TiO2, the Δn became smaller in the modified region and some of them showed relatively large decrease of the Δn, Δn < −0.01, with about 10 μm width. Such a glass material could be useful for the compact optics and optical devices. 相似文献
946.
Dr. Kiyoung Park Tomohiro Tsugawa Prof. Dr. Hideki Furutachi Yeonju Kwak Lei V. Liu Dr. Shaun D. Wong Dr. Yoshitaka Yoda Prof. Dr. Yasuhiro Kobayashi Dr. Makina Saito Masayuki Kurokuzu Prof. Dr. Makoto Seto Prof. Dr. Masatatsu Suzuki Prof. Dr. Edward I. Solomon 《Angewandte Chemie (International ed. in English)》2013,52(4):1294-1298
947.
948.
949.
Tomohiko Inomata Mayuka Hatano Yuya Kawai Ayaka Matsunaga Takuma Kitagawa Yuko Wasada-Tsutsui Tomohiro Ozawa Hideki Masuda 《Molecules (Basel, Switzerland)》2021,26(22)
To develop low-cost and efficient dye-sensitized solar cells (DSSCs), we designed and prepared three homoleptic Cu(I) complexes with asymmetric ligands, M1, M2, and Y3, which have the advantages of heteroleptic-type complexes and compensate for their synthetic challenges. The three copper(I) complexes were characterized by elemental analysis, UV-vis absorption spectroscopy, and electrochemical measurements. Their absorption spectra and orbital energies were evaluated and are discussed in the context of TD-DFT calculations. The complexes have high VOC values (0.48, 0.60, and 0.66 V for M1, M2, and Y3, respectively) which are similar to previously reported copper(I) dyes with symmetric ligands, although their energy conversion efficiencies are relatively low (0.17, 0.64, and 2.66%, respectively). 相似文献
950.
Noboru Matsumura Yasuyo Shimizu Yoshio Yagyu Hiroo Inoue Kazuhiko Mizuno Tomohiro Adachi 《Heteroatom Chemistry》1998,9(4):387-397
The reaction of tetrachlorocyclopropene (1) with arenethiols (2a–e), followed by treatmentwith perchloric acid, gave tris(arylthio)cyclopropenylium perchlorates (3a–c and e), 1,1,2,3,3-pentakis(arylthio)-1-propenes (4a–d), and 2,3,3-tris(arylthio)propenals (5a–d). The structures of tris(phenylthio)cyclopropenylium perchlorate (3a), 1,1,2,3,3-pentakis(phenylthio)-1-propene (4a), and 2,3,3-tris(o-tolylthio)propenal (5b) were analyzed by single-crystal X-ray diffraction studies. The yields depended significantly on the electron-withdrawing property of the substituents of the arenethiols and the molar ratio of 2 to 1. The reaction with 2,6-dimethylbenzenethiol (2e) gave only tris(2,6-dimethylphenylthio)cyclopropenylium perchlorate (3e) without the formation of 4e and 5e. Compounds 5a–d were produced by acid hydrolysis of 4a–d. Pyrolysis of 4a–d gave (3R,4S)-1,1,2,3,4,5,6,6-octakis(arylthio)-1,5-hexadienes (9a–d) and 1,1,2,5,6,6-hexakis(arylthio)-(3E)-1,3,5-hexatrienes (10a–d) together with diaryl disulfides (11a–d). Compound 10a was also produced by photolysis. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:387–397, 1998 相似文献