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51.
Xiang H Lan Y Li HY Jiang L Lu TB Anson CE Powell AK 《Dalton transactions (Cambridge, England : 2003)》2010,39(20):4737-4739
Isostructural Co(II)?Co(III)?Ln(III)? (Ln = Y (1), Gd (2) and Dy (3)) coordination clusters formed using the ligand Tris are the first examples of 3d-4f complexes involving this ligand and show weak ferromagnetic coupling between the Co(II) ions and slow relaxation (SMM) behaviour for 3. 相似文献
52.
Jing-Jing Zhu Chao-Feng Zhang Mian Zhang S.W. Annie Bligh Li Yang Zhi-Min Wang Zheng-Tao Wang 《Journal of chromatography. A》2010,1217(33):5384-5388
Six C-glucosyl anthrones were characterized as three pairs of epimers by on-line high performance liquid chromatography–circular dichroism (HPLC–CD) analysis and isolated from the roots of Rumex dentatus by column chromatography. Their structures were elucidated by mass spectrometry, nuclear magnetic spectroscopy and HPLC–CD analysis. They are 10R-C-β-d-glucosyl-10-hydroxyemodin-9-anthrone (rumejaposide E, 1) and 10S-C-β-d-glucosyl-10-hydroxyemodin-9-anthrone (rumejaposide F, 2), 10R-C-β-d-glucosylemodin-9-anthrone (rumejaposide G, 3) and 10S-C-β-d-glucosylemodin-9-anthrone (rumejaposide H, 4), 10S-C-β-d-glucosyl-10-hydroxychrysophanol-9-anthrone (cassialoin, 5) and 10R-C-β-d-glucosyl-10-hydroxychrysophanol-9-anthrone (rumejaposide I, 6). Rumejaposides F–I (2–4 and 6) were new C-glucosyl anthrones. Rumejaposide E (1) and cassialoin (5) were isolated for the first time in Rumex plants. On-line HPLC–UV–CD analysis was a useful tool for structure elucidating epimeric C-glycosides anthrones 3–6 because of the poor stability of the pure isomers (3 and 4) and the minute quantity of 5 and 6 in the mixture. 相似文献
53.
Vigreux C Barthélémy E Bastard L Broquin JE Barillot M Ménard S Parent G Pradel A 《Optics letters》2011,36(15):2922-2924
The feasibility of all-telluride integrated optics devices based on waveguides presenting a single-mode behavior in the spectral range (10-20 μm) is demonstrated. These waveguides are constituted of a several micrometer thick Te(82)Ge(18) film deposited onto a Te(75)Ge(15)Ga(10) bulk glass substrate by thermal coevaporation and further etched by reactive ion etching under the CHF(3)/O(2)/Ar atmosphere. The obtained structures were proven to behave as channel waveguides with a good single-mode transmission over the whole spectral range. These results allowed validating our technological solution for the fabrication of integrated optics modal filters for spatial interferometry. 相似文献
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Syntheses of several new 3,4‐dihydropyrimidinones (DHPMs) on sodium sulfate solid support have been reported. The microwave enhanced rapid synthesis of the title compounds yielded a good percentage of the DHPMs. The catalytic activity of indium triflate enables to prepare a wide range of DHPMs. Syntheses of 2‐hydroxyphenyl, 2‐hydroxy‐4‐methoxyphenyl pendant groups on DHPMs scaffold are advantages of the present method, which are rather prone towards cyclization and the presence of free hydroxyl groups on the phenyl ring is confirmed via D2O exchange study. The mechanism of the reaction is expected to proceed via absorption of substrates on the solid support followed by promotion of the reaction by In(OTf)3 coupled with microwave irradiation. 相似文献
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