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921.
<正>According to ultraviolet(UV)-vis absorption spectra recorded in the DNA metallization process,DNA-templated Co/Cu binary nanoparticle chains are fabricated by incubating genome DNA of paralichthys olivaceus muscle in CoCl_2 and CuCl_2 mixture solution for 20 hours and reducing the complex for 2 hours.Transmission electron microscopy observation indicates that Co and Cu nanoparticles with 20 nm in diameter were randomly dispersed on the DNA template. The superconducting quantum interference device(SQUID) measurements display that the magnetic interaction between cobalt particles is greatly decreased by the copper particle.With increasing copper content,the coercivity of the systems enhance from 9 Oe to 100 Oe(1 Oe=79.5775 A/m). 相似文献
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Kanji Takahashi Michihiro Kawabata Daisuke Uemura Shuichi Iwadare Ryuji Mitomo Fumio Nakano Akinori Matsuzaki 《Tetrahedron letters》1985,26(8):1077-1078
Based on the spectroscopic analysis and correlation with the degradation products of oxazolomycin, the structure of neooxazolomycin has been elucidated. 相似文献
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Kentaro Hirai Hirohiko Sugimoto Teruyuki Ishiba Toshio Fujishita Yuji Tsukinoki Katsumi Hirose 《Journal of heterocyclic chemistry》1982,19(6):1363-1369
The synthesis of (5-acylaminomethyl-3-carbamoyl-1H-1,2,4-triazol-1-yl)benzophenone derivatives 4a-i, 14a-d, 15a-d, 16a-c , is described. Acylation of the key intermediate, 1-benzoylphenylazo-1-aminoacetamide 7, followed by cyclization in the presence of acid afforded 1H-1,2,4-triazole derivatives. These compounds were evaluated for their central nervous system (CNS) activity. Some of these compounds exhibited high activities in anti-pentylene tetrazole and rotarod test in mice when orally administered. 相似文献
929.
Mizuno M Goto K Miura T Hosaka D Inazu T 《Chemical communications (Cambridge, England)》2003,(8):972-973
Three new fluorous supports for peptide synthesis, i.e., the trialkoxybenzhydryl-type (6), the Wang-type (7) and the tert-butyl-type support (8), were prepared. A bioactive peptide TRH was easily synthesized by an Fmoc strategy using the benzhydryl-type fluorous support with fluorous chemistry. 相似文献
930.
The direct reductive amination (DRA) of carbonyl compounds with amines has been achieved using homogenous iridium catalyst and gaseous hydrogen. It appeared that the cationic iridium catalyst, [Ir(cod)2]BF4, without any other ligands was sufficient for the reaction. For the DRA of the ketone substrates, an ionic liquid, [Bmim]BF4, was found to be superior to the other organic solvent used. Especially, the counter anion of the ionic liquid has a significant influence on the selectivity, and at the same time, a high reaction temperature was found to be crucial for the excellent selectivity. 相似文献