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971.
Tsuchida Shirou Takahashi Rina Yabe Kurumi Hamaue Naoya Aoki Takashi 《Cellulose (London, England)》2022,29(6):3025-3033
Cellulose - A method for the preparation of dialdehyde cellulose disks (DACD) and subsequent diamino cellulose disks (DAmCD) was developed. DACD was prepared by oxidizing filter paper with sodium... 相似文献
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Terminal acetylenes were converted to acetylenecarboxylates in high yields under atmospheric pressure of carbon monoxide at room temperature using a catalytic amount of PdCl2 and a stoichiometric amount of CuCl2. 相似文献
977.
Kiyotaka Koyama Masahiro Ishino Takashi Sugita Kunio Takahashi 《Tetrahedron letters》2004,45(37):6947-6948
Phomactin H (1), a diterpene has been isolated from cultures of an unidentified marine-derived fungus. The structure and relative stereochemistry of phomactin H (1) was determined by X-ray diffraction analysis. Phomactin H (1), having an oxepane moiety, is a new phomactin with a novel skeleton. 相似文献
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Hirokazu Shimooka Tadashi Yamamoto Seiji Takahashi Shigemi Kohiki 《Journal of Sol-Gel Science and Technology》2000,19(1-3):749-752
Synthesis of free-standing crystalline barium titanate (BaTiO3) films at vapor/liquid or liquid/liquid interface at room temperature has been investigated. High concentration Ba, Ti alkoxides precursor solution (1.2 mol/l) or pre-hydrolyzed precursor solutions by water vapor in a H2O/Ba molar ratio of 0 to 6 were used as dropping solutions at the interfaces. Transparent gel films were formed when partially hydrolyzed precursors (H2O/Ba = 2 to 3) were spread out on a N2/liquid paraffin interface. The films shrank from syneresis and vaporization of the solvent during aging at room temperature. As a result, free-standing transparent films with a thickness of around 1 m and little stoichiometric deviation were obtained by separation from the liquid surface and rinse by hexane. The films consisted of crystalline BaTiO3 particles of less than a few nanometers. Nanostructured dense BaTiO3 free-standing films with a grain size less than 100 nm were obtained at 1030°C. 相似文献
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A 24-member combinatorial library based on the structure of aeruginosin 298-A (1a) was synthesized utilizing solid-phase, and their inhibitory activity against trypsin was evaluated. Among the library, we found that D-Hpla-D-Leu-L-Choi-Agma (1h) is 300 times more potent than the parent natural product 1a. 相似文献
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