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41.
We synthesized new porous coordination polymers (PCPs) {Ln(III)[Co(III)(dcbpy)(3)]·nH(2)O} (Ln = La(3+), Nd(3+), Gd(3+); H(2)dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) and characterized them by X-ray diffraction and vapor-adsorption measurements. These three Ln-Co-based PCPs have similar rock-salt types and highly symmetrical porous structure and show a reversible structural collapse-regeneration accompanied by water-vapor desorption-adsorption. Similar structural regeneration was also observed for the Gd-Co PCP upon exposure to MeOH and CH(3)CN vapors, whereas the remaining two PCPs barely responded to organic vapors. 相似文献
42.
The synthesis and characterization of two coordination polymers, {Cu(I)[Mo(V)(bdt)(3)]·0.5Et(2)O}(n) (1·0.5Et(2)O, bdt: o-benzenedithiolato) and {Ag(I)[Mo(V)(bdt)(3)]}(n) (2), composed of redox-active [Mo(V)(bdt)(3)](-) metalloligand with Cu(I) and Ag(I) ions are reported. The complexation reactions of [Mo(V)(bdt)(3)](-) with Cu(II)(ClO(4))(2) or Ag(I)ClO(4) commonly lead to the formation of one-dimensional (1-D) coordination polymers. The presence of Cu(I) in 1·0.5Et(2)O strongly indicates that the Cu(II) ion is reduced during the complexation reaction with [Mo(V)(bdt)(3)](-), which acts as an electron donor. The total dimensionalities of the assembled structures of 1·0.5Et(2)O and 2 are significantly different and related to the type of additional metal ions, Cu(I) and Ag(I). In contrast to the isolated 1-D chain structure of 1·0.5Et(2)O, complex 2 has a three-dimensional (3-D) assembled structure constructed from additional π-π stacking interactions between adjacent [Mo(V)(bdt)(3)](-) moieties. These structural differences influence the solubility of the complexes in organic solvents; complex 1·0.5Et(2)O is soluble as origomeric species in highly polar solvents, while 2 is insoluble in organic solvents and water. Coordination polymers 1·0.5Et(2)O and 2 were investigated by UV-vis spectroscopy in the solid state, and that in solution together with their electrochemical properties were also investigated for 1 because of its higher solubility in polar organic solvents. Complex 1·0.5Et(2)O dissolved in CH(3)CN demonstrates concentration-dependent UV-vis spectra supporting the presence of coordinative interactions between [Mo(V)(bdt)(3)](-) moieties and Cu(I) ions to create the origomeric species even in solutions, an observation that is supported also by electrochemical experiments. 相似文献
43.
Yuzuru Hayashi Rieko Matsuda Katsutoshi Ito Waka Nishimura Kazuhiro Imai Masako Maeda 《Analytical sciences》2005,21(2):167-169
This paper theoretically derives a general rule that while the slope of the semi-logarithmic plot (Y vs. log X) of a calibration curve varies depending on analyte concentration, X, the slope takes a specific value at the detection limit (L(D)). This rule holds good irrespective of the shape of the calibration curve (linear or non-linear) and in this paper, is applied to competitive ELISA (enzyme linked immunosorbent assay). The following relationship is deduced: slope of log-dose B/B0 at L(D) = [relative standard deviation (RSD) of blank responses] / 0.13. The L(D) obtained from the above-mentioned slope corresponds to the dose at which the RSD of dose estimates is 0.3 (= 30%). A commercial kit for 17alpha-hydroxyprogesterone is taken as an example. 相似文献
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45.
Yoshinori Fujimoto Miki Kimura Akihiro Takasu Fathy A.M. Khalifa Masuo Morisaki Nobuo Ikekawa 《Tetrahedron letters》1984,25(14):1501-1504
Deuterated stigmasterols (10, 11 and 12) were chemically synthesized and fed to silk-worm larvae. GC-MS analysis of the metabolites, cholesterol (4) and desmosterol (6), indicates the migration of 25-hydrogen to C-24 position during stigmasterol dealkylation. 22,24(28)-Dienes(8a and 8b) were shown to be converted to 22,24-diene (5), desmosterol and cholesterol. 相似文献
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48.
Maeda H Yamamoto K Nomura Y Kohno I Hafsi L Ueda N Yoshida S Fukuda M Fukuyasu Y Yamauchi Y Itoh N 《Journal of the American Chemical Society》2005,127(1):68-69
Fluorometric detection of O2-* is performed based on desulfonylation of 3 to the corresponding fluoresceins 4 through nucleophilic substitution, and this fluorescing process is quite specific toward O2-* over H2O2, t-BuOOH, NaOCl, 1O2, HO*, NO*, and ONOO-. Furthermore, effects of glutathione, cytochrome P450 reductase/NADPH, and diaphorase/NADH are relatively small on the fluorescing process of probe 3 with X = Y = F, which is useful to detect O2-* released from neutrophils stimulated by phorbol myristate acetate with satisfactory sensitivity. 相似文献
49.
The proton magnetic resonance spectrum of diethylmethylvinylammonium bromide, in which splittings due to 14N, 1H spin couplings are clearly observed as strongly perturbed second-order patterns, has been analysed and the difference in the substituent effect between a methyl and an ethyl group upon 1H, 1H and 14N, 1H spin couplings are summarised. 相似文献
50.
Masako Bando Takashi Okazaki Kanji Fujii 《Zeitschrift fur Physik C Particles and Fields》1982,12(1):17-22
Structures of the matrix elements of two-and four-quark operators are investigated in connection with the argument of “helicity suppression” in the decay amplitudes. The analysis is made by expanding the quark operators in terms of the constituentquark modes in a relativistic way. It is shown that the naive consideration of helicity suppression can be applied to the case of two-quark operators. The situation is quite different in the case of four-quark operators; sometimes we find maximum value of the decay amplitude, which is suppressed according to the naive helicity suppression. It is made clear which aspects of the constituent-quark picture are essential to cause the difference between our results and those from the free quark picture. Remarks are given on nonleptonic decays ofK-andD-mesons. 相似文献