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91.
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J A Meriluoto J E Eriksson K Harada A M Dahlem K Sivonen W W Carmichael 《Journal of chromatography. A》1990,509(2):390-395
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Yoshimi Yamaguchi Yoshihisa Okamoto Kazuho Harada 《Journal of heterocyclic chemistry》1999,36(4):841-847
The revision of the structure of hydrolytic product from 4-cyano-1-ethoxypyrirnido[1,6-a]benzimidazole (1) and the properties of ethyl (2-benzimidazolyl)cyanoacetimidate (3a) are described. 相似文献
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The uniqueness of a binary doubly-even self-dual [48, 24, 12] code is used to prove that a self-orthogonal 5-(48, 12, 8) design, as well as some of its derived and residual designs, including a quasi-symmetric 2-(45, 9, 8) design, are all unique up to isomorphism.Received November 5, 2003 相似文献
98.
-Ni(H2O)6 · SO4 and its selenate derivative exhibit chirality only in the solid-state. We have observed, for the first time, a sign inversion of CD (circular dichroism) in the 3A2g → 3T1g(P) Ni(II) d–d transition at near liquid nitrogen temperatures. The novel finding was achieved by building a new cooling unit to a solid-state specialized Universal Chiroptical Spectrophotometer (UCS-1) [R. Kuroda, T. Harada, Y. Shindo, Rev. Sci. Instrum. 72 (2001) 3802.] and by formulating an analytical procedure to obtain artifact-free CD signals based on the Mueller matrix method. The sign inversion is remarkable as the crystal structure hardly changes from 300 to 100 K. The origin of the sign inversion is discussed. 相似文献
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Harada T Ikeda S Hashimoto F Sakata T Ikeue K Torimoto T Matsumura M 《Langmuir : the ACS journal of surfaces and colloids》2010,26(22):17720-17725
A core-shell composite consisting of a palladium (Pd) nanoparticle and a hollow carbon shell (Pd@hmC) was employed as a catalyst for aerobic oxidation of various alcohols. The core-shell structure was synthesized by consecutive coatings of Pd nanoparticles with siliceous and carbon layers followed by removal of the intermediate siliceous layer. Structural characterizations using TEM and N(2) adsorption-desorption measurements revealed that Pd@hmC thus-obtained was composed of a Pd nanoparticle core of 3-6 nm in diameter and a hollow carbon shell with well-developed mesopore (ca. 2.5 nm in diameter) and micropore (ca. 0.4-0.8 nm in diameter) systems. When compared to some Pd-supported carbons, Pd@hmC showed a high level of catalytic activity for oxidation of benzyl alcohol into benzaldehyde using atmospheric pressure of O(2) as an oxidant. The Pd@hmC composite also exhibited a high level of catalytic activity for aerobic oxidations of other primary benzylic and allylic alcohols into corresponding aldehydes. The presence of a well-developed pore system in the lateral carbon shell enabled efficient diffusion of both substrates and products to reach the central Pd nanoparticles, leading to such high catalytic activities. This core-shell structure also provided high thermal stability of Pd nanoparticles toward coalescence and/or aggregation due to the physical isolation of each Pd nanoparticle from neighboring particles by the carbon shell: this specific property of Pd@hmC resulted in possible regeneration of catalytic activity for these aerobic oxidations by a high-temperature heat treatment of the sample recovered after catalytic reactions. 相似文献