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891.
Noriko Shimizu Tomoji Ozeki Hideyasu Shikama Tsuneji Sano Masahiro Sadakane 《Journal of Cluster Science》2014,25(3):755-770
We found that three isomers of mono-Ru substituted Keggin-type germanotungstate with a dmso ligand, [GeW11O39RuII(dmso)]6?, could be formed by a reaction of α-Keggin-type mono-lacunary germanotungstate, [α-GeW11O39]8?, with Ru(dmso)4Cl2. The main isomer is an α-isomer, and the others are β2-isomer and β3-isomer, which were confirmed by 1H NMR, cyclic voltammetry, IR, and single crystal X-ray structure analysis. 相似文献
892.
893.
Junpei Miyake Keita Fukasawa Masahiro Watanabe Kenji Miyatake 《Journal of polymer science. Part A, Polymer chemistry》2014,52(3):383-389
Five kinds of ammonium groups functionalized partially fluorinated poly(arylene ether) block copolymer membranes were prepared for investigating the structure–property relationship as anion exchange membranes (AEMs). Consequently, the pyridine (PYR)‐modified membrane showed the highest alkaline and hydrazine stability in terms of the conductivity, water uptake, and dry weight. The chloromethylated precursor block copolymers were reacted with amines, such as trimethylamine, N‐butyldimethylamine, 1‐methylimidazole, 1,2‐dimethylimidazole, and PYR to provide the target quaternized poly(arylene ether)s. The structures of the polymers, as well as model compounds and oligomers were well characterized by 1H NMR spectra. The obtained AEMs were subjected to water uptake and hydroxide ion conductivity measurements and stabilities in aqueous alkaline and hydrazine media. The pyridinium‐functionalized quaternized polymers membrane showed the highest alkaline and hydrazine stability with minor losses in the conductivity, water uptake, and dry weight. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 383–389 相似文献
894.
We report herein an effective method for the construction of 4- and 7-ring benzo-fused thieno[3,2-b]thiophenes, involving palladium-catalyzed intramolecular decarboxylative arylation as the key step. 相似文献
895.
Back Cover: Tailoring Intermolecular Interactions for Efficient Room‐Temperature Phosphorescence from Purely Organic Materials in Amorphous Polymer Matrices (Angew. Chem. Int. Ed. 42/2014) 下载免费PDF全文
Sungbaek Seo Jaehun Jung Prof. Dr. Jinsang Kim 《Angewandte Chemie (International ed. in English)》2014,53(42):11382-11382
896.
897.
Yohei SatoYusai Ito Shigeru Okada Masahiro MurakamiHiroki Abe 《Tetrahedron letters》2003,44(37):7035-7037
The green microalga Botryococcus braunii race B accumulates two types of triterpenoid hydrocarbons, botryococcenes and tetramethylsqualene. Both triterpenoids are synthesized via the non-mevalonate pathway. 相似文献
898.
899.
S. I. Yun Ki-Dong Oh Kwon-Sang Ryu Chang-Geon Kim H. L. Park H. J. Seo Chae Kum 《Applied physics. B, Lasers and optics》1986,40(2):95-98
We have used a modified photothermal probe beam deflection system with a back pumping configuration for the measurements of the temperature-dependent thermal diffusivity of atmospheric air. The results are consistent and reasonably well agree with the literature values. The measured thermal diffusivity values are the same for the same measuring temperature regardless of the beam offsets and the deflecting surface temperatures. For the gas with known temperature-dependent thermal diffusivity, this method can be used to deduce the temperature of a gas from the measured thermal diffusivity value. 相似文献
900.
Masahiro Yasumoto 《Archive for Mathematical Logic》2005,44(6):685-688
We prove that PTCN(n) (the polynomial time closure of the nonstandard natural number n in the model N of S2.) cannot be a model of U12. This implies that there exists a first order sentence of bounded arithmetic which is provable in U12 but does not hold in PTCN(n). 相似文献