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1.
Watanabe Sou Senzaki Tatsuya Shibata Atsuhiro Nomura Kazunori Takeuchi Masayuki Nakatani Kiyoharu Matsuura Haruaki Horiuchi Yusuke Arai Tsuyoshi 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(3):1273-1277
Journal of Radioanalytical and Nuclear Chemistry - Extraction chromatography flow-sheet employing octyl(phenyl)-N,N-diisobutylcarbonoylmethylphosphine oxide and bis(2-ethylhexyl) hydrogen phosphate... 相似文献
2.
Atsuhiro Fujimori Mikako Ishitsuka Hiroo Nakahara Eisuke Ito Masahiko Hara Kaname Kanai Hisao Ishii Yukio Ouchi Kazuhiko Seki 《Journal of Polymer Science.Polymer Physics》2004,42(12):2329-2336
Photopolymerization of cadmium 10,12-pentacosadiynoate (CdDA) in Langmuir–Blodgett (LB) films, with the molecular packing well arranged by moderate preannealing, was investigated with near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. Greenish films of polydiacetylene with an absorption wavelength of 705 nm were obtained through the photopolymerization of preannealed monomer LB films, and this resulted in an extended π-conjugate system based on the well-ordered monomer in a two-dimensional arrangement. The electronic structures of the polydiacetylenes were found to be correlated to the variation of the molecular arrangements in the films from the changes in the NEXAFS spectra through photopolymerization in the LB films. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2329–2336, 2004 相似文献
3.
An m‐covering of a graph G is a spanning subgraph of G with maximum degree at most m. In this paper, we shall show that every 3‐connected graph on a surface with Euler genus k ≥ 2 with sufficiently large representativity has a 2‐connected 7‐covering with at most 6k ? 12 vertices of degree 7. We also construct, for every surface F2 with Euler genus k ≥ 2, a 3‐connected graph G on F2 with arbitrarily large representativity each of whose 2‐connected 7‐coverings contains at least 6k ? 12 vertices of degree 7. © 2003 Wiley Periodicals, Inc. J Graph Theory 43: 26–36, 2003 相似文献
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5.
Tetra- and dinuclear Zn(II) N-confused porphyrin dimers (1, 2) and pyridine-coordinating Zn(II) monomer complex (3) were synthesized, and the ditopic, inner and outer coordination of Zn metal in the dimer complex (1) was demonstrated by X-ray analyses. 相似文献
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7.
High-performance liquid chromatography of coenzyme Q-related compounds and its application to biological materials 总被引:1,自引:0,他引:1
T Okamoto K Fukui M Nakamoto T Kishi T Okishio T Yamagami N Kanamori H Kishi E Hiraoka 《Journal of chromatography. A》1985,342(1):35-46
A convenient and precise method for the separation and determination of coenzyme Q (CoQ)-related compounds (CoQ homologues, plastoquinone-9, ubichromenol-9, etc.) was developed using high-performance liquid chromatography (HPLC). All compounds tested were separated using a reverse-phase column with a suitable mobile phase and detected at a wavelength of 275 nm. CoQ extracts in plasma and erythrocytes were purified by thin-layer chromatography prior to HPLC analysis, but such purification was not necessary when determining CoQ in urine and tissues. Hydroquinone forms of CoQ existing in animal tissues were oxidized to the corresponding quinone forms with potassium hexacyanoferrate(III). This HPLC method was applied satisfactorily to the determination of the contents of CoQ homologues in human and animal samples. CoQ10 was the only homologue detected in human samples, and CoQ8, CoQ9 and CoQ10 were native homologues of CoQ in rat tissues. Ubichromenol-9 and plastoquinone-9 were not detected in these samples. 相似文献
8.
Sato H Tashiro K Shinmori H Osuka A Aida T 《Chemical communications (Cambridge, England)》2005,(18):2324-2326
Upon complexation with 4,4[prime or minute]-bipyridine, a cyclic dimer of a fused porphyrin zinc complex, having two pi-electronically coupled binding sites, shows a strong negative cooperativity in the second guest binding, to allow stepwise formation of 1 : 1 and 1 : 2 inclusion complexes. 相似文献
9.
N-confused 5,20-diphenylporphyrin (NCDPP, 1) formed 2:2 dimer complexes with group 12 metals both in the solid state and in solution. X-ray single-crystal analyses of the Zn(II) and Cd(II) complexes (7, 8) revealed that each metal ion is coordinated with three inner core nitrogens and a peripheral nitrogen of the other NCDPP in the pair. In the (1)H NMR spectra of 7, 8, and the Hg(II) complex (9), the outer alpha-H signals of the confused pyrrole ring appeared in the upfield region at 2.57, 3.44, and 3.60 ppm, respectively, due to the ring current effect by the coordinated porphyrins. In the case of the Cd(II) and Hg(II) complexes (8, 9), additional magnetic couplings with the metal nuclei of the partner rings were observed. The equilibrium constants (K) of the monomer exchange reaction at 25 degrees C were determined to be 2.5, 1.3, and 0.6 for the (Zn-Cd), (Cd-Hg), and (Zn-Hg) heterodimer complexes, respectively, from the (1)H NMR spectra of a solution containing two different dimers. Furthermore, a metal-transfer reaction from a Zn(II) NCP dimer complex to the free base porphyrin was demonstrated. 相似文献