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111.
Zhihuang Chen 《Talanta》2007,72(4):1410-1415
In this paper, the electrochemiluminescence (ECL) behavior of bis-[3,4,6-trichloro-2-(pentyloxycarbonyl)-phenyl] oxalate (BTPPO) at glassy carbon electrode (GCE) in phosphate buffer solution in the presence of hydrogen peroxide has been investigated when linear sweep voltammetry was applied. The optimum chemical conditions and electrochemical parameters for this ECL system have been investigated in detail. Under the optimum conditions, it was found that the concentration of BTPPO was linear with the ECL intensity in the range of 3.0 × l0−6 to 3.0 × 10−4 mol/L, and the detection limit (S/N = 3) for BTPPO was 1.0 × 10−7 mol/L. The possible mechanism for ECL of BTPPO at the GCE in the presence of hydrogen peroxide was also discussed. Furthermore, based on the fact that glucose oxidase can react with glucose to produce hydrogen peroxide, a new ECL sensing system of BTPPO has been developed for detection of glucose. The enhanced ECL intensity has a linear relationship with the concentration of glucose in the range of 1.0 × l0−4 to 1.0 × 10−3 mol/L, and the detection limit for glucose is found to be 5.0 × 10−5 mol/L (S/N = 3).  相似文献   
112.
黄美华  刘平  王艰  陈云  刘政 《结构化学》2006,25(4):453-458
1 INTRODUCTION The polymeric metal complexes with extended structures are of great interest because of their useful chemical or physical properties[1]. Due to the noti- ceable fact that the aromatic polycarboxylate can provide versatile coordination mode and the non- coplanar structure of carboxylate groups and benze- ne rings, a lot of efforts in this field have been parti- cularly directed to the preparation of aromatic poly- carboxylate (such as phthalate, terephthalate and isophthalat…  相似文献   
113.
Yang W  Lu C 《Inorganic chemistry》2002,41(22):5638-5640
The novel tubular framework of [(V(IV)O)(3)(mu(4)-PO(4))(2)(2,2'-bpy)(mu-OH(2))].1/3H(2)O, which was synthesized from hydrothermal reaction, possesses some attractive structural features: (i) O=V(IV)O(4)(OH(2)) octahedra and PO(4) tetrahedra linked together by corner-sharing and face-sharing into a cylinder-shaped channel including 6 water molecules per cell unit, and (ii) (VO)(2,2'-bpy) groups regularly arranged around the tube, so that the 2,2-bpy ligands constitute an organic shell around an aqueous polar channel.  相似文献   
114.
Pd nanoparticles have been successfully supported on nanoscale metal-organic frameworks (NMOFs) by using a simple and effective microwave-assisted impregnation process. The resulting composite, representing as a highly active NMOFs supported metal nanoparticles catalyst for the Suzuki cross-coupling reaction between aryl/heteroaryl halides and arylboronic acids, is well characterized, and its high activity and good recyclability are discussed in details. It reveals that, compared to the corresponding bulk MOFs and conventional active carbon materials, nanoscale MOFs as novel support materials for heterogeneous catalysts can exhibit superior performance in the catalytic reactions.  相似文献   
115.
Konjac glucomannan (KGM) was aminated by 2-chloroethyl-amine (CEA) as reagent so as to study the influence of concentration of CEA (based on the amount of KGM), concentration of NaOH, reaction time and temperature on the extent of amination. And the molecular simulation technology was adopted to analyze the conformation stability of aminate (AKGM). The results indicate that when the amount of CEA is higher, the extent of amination is higher. The optimum concentration of NaOH, reaction time and temperature are 10% NaOH, 70 ℃ and 45 rain, respectively. IR shows KGM is successfully aminated. The conformation of AKGM is in a random clew-like shape.  相似文献   
116.
117.
The Rh-catalyzed ortho-C(sp2)−H functionalization of 8-aminoquinoline-derived benzamides with aliphatic acyl fluorides generated in situ from the corresponding acids has been developed. This reaction initiated with 8-aminoquinoline-directed ortho-C(sp2)−H acylation, which was accompanied by subsequent intramolecular nucleophilic acyl substitution of amide group to produce alkylidene phthalides This approach exhibits high stereo-selectivity for Z-isomer products, and tolerates a variety of functional groups as well as aliphatic carboxylic acids with diverse structural scaffolds.  相似文献   
118.
A cobalt-poor or iron rich bicomponent mixture of Co0.9Fe2.1O4/Fe2O3 and Co0.8Fe2.2O4/Fe2O3 anode materials have been successfully prepared using simple, cost-effective, and scalable urea-assisted auto-combustion synthesis. The threshold limit of lower cobalt stoichiometry in CoFe2O4 that leads to impressive electrochemical performance was identified. The electrochemical performance shows that the Co0.9Fe2.1O4/Fe2O3 electrode exhibits high capacity and rate capability in comparison to a Co0.8Fe2.2O4/Fe2O3 electrode, and the obtained data is comparable with that reported for cobalt-rich CoFe2O4. The better rate performance of the Co0.9Fe2.1O4/Fe2O3 electrode is ascribed to its unique stoichiometry, which intimately prefers the combination of Fe2O3 with Co1−xFe2+xO4 and the high electrical conductivity. Further, the high reversible capacity in Co0.9Fe2.1O4/Fe2O3 and Co0.8Fe2.2O4/Fe2O3 electrodes is most likely attributed to the synergistic electrochemical activity of both the nanostructured materials (Co1−xFe2+xO4 and Fe2O3), reaching beyond the well-established mechanisms of charge storage in these two phases.  相似文献   
119.
AFe3O(PO4)3 (A = Ca, Sr and Pb) powder compounds were studied by means of X-ray diffraction (XRD), electron-probe microanalysis (EPMA) coupled with wavelength dispersion spectroscopy (WDS), Raman and diffuse reflectance spectroscopies, specific heat and magnetic properties measurements. Magnetization, magnetic susceptibility and specific heat measurements carried out on AFe3O(PO4)3 (A = Sr, Ca and Pb) powders firmly establish a series of three ferromagnetic (FM)-like second order phase transitions spanned over the 32–8 K temperature range. Room temperature Mössbauer spectroscopy and associated DFT calculations confirm the existence of three crystallographically non equivalent Fe3+ sites in the three compounds. Mössbauer spectra recorded as a function of temperature in the PbFe3O(PO4)3 compound also establishes the occurrence of two purely magnetic and reversible phase transitions at 32 and 10 K. Diffuse reflectance measurements reveal two broad absorption bands at 1047 and 837 nm, in both PbFe3O(PO4)3 and SrFe3O(PO4)3 powders, with peak cross sections ∼10−20 cm2 typical of spin-forbidden and forced electric dipole intraconfigurational transitions.  相似文献   
120.
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