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71.
The voltammetric behavior of the LMF-Mg(II) complex with DNA at a mercury electrode is reported for the first time. In NH3–NH4Cl buffer (pH=9.10), the adsorption phenomena of the LMF–Mg(II) complex were observed by linear sweep voltammetry. The mechanism of the electrode reaction was found to be a reduction of LMF in the complex, and the composition of the LMF–Mg(II) complex is 2:1. In the presence of calf thymus DNA (ctDNA), the peak current of LMF–Mg(II) complex decreased considerably, and a new well-defined adsorptive reduction peak appeared at −1.63 V (vs. SCE). The electrochemical kinetic parameters and the binding number of LMF–Mg(II) with ctDNA were also obtained. Moreover, the new peak currents of LMF–Mg(II)–DNA system increased linearly correlated to the concentration of DNA in the 4.00×10−7–2.60×10−6 g ml−1 range when the concentrations of LMF–Mg(II) complex was fixed at 5.00×10−6 mol l−1, with the detection limits of 2.33×10−7 g ml−1. An electrostatic interaction was suggested by electrochemical method. 相似文献
72.
Nan Zhou 《Mikrochimica acta》1991,105(4-6):159-162
Proposed in this paper is an improved method for removal of tin as the matrix element by volatilization in an anhydrous medium as mixed halides of different composition. Any one of them boils at a lower temperature than SnBr4. This ternary system enhances the eventual recombination of temporarily dissociated species to volatile ones, thus making the process quicker and more efficient. The presence of 2 mg of Pb(II) suffices to prevent Bi(III) from loss due to volatilization. 相似文献
73.
Li Qiu WANG Xiao Jun PENG* Rong ZHANG Guo Quan XU Jing Nan CUI State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 《中国化学快报》2003,(1)
Indocyanine dyes as fluorescent labeling reagents have been used in bioanalysis1,2. Arylsulfonate indocyanine dyes 1d and 1e developed by Waggoner A. S. et al.3,4 have excellent fluorescent properties combined with good aqueous solubility, are a new generation of fluorescent label compounds for proteins, oligonucleotides and other compounds containing hydroxyl, mercaptol or primary amine groups5. However, photostability of these dyes has been a problem. Z. G. YAO et al.6 reported that p… 相似文献
74.
Schumm BA Koetke DS Adolphsen CE Alexander JP Averill D Barish BC Barklow T Barnett BA Blockus D Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan JM Drell PS Drewer DC Durrett D Elia R Feldman GJ Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Hanson G Harr R Harral B Harris FA Hayes K Hearty C Heusch CA Hildreth MD Himel T Hinshaw DA 《Physical review D: Particles and fields》1992,46(1):453-456
75.
Alam MS Kim IJ Nemati B O'Neill JJ Romero V Severini H Sun CR Wang P Zoeller MM Crawford G Fulton R Gan KK Kagan H Kass R Lee J Malchow R Morrow F Sung M White C Whitmore J Wilson P Butler F Fu X Kalbfleisch G Lambrecht M Skubic P Snow J Bortoletto D Brown DN Dominick J McIlwain RL Miao T Miller DH Modesitt M Schaffner SF Shibata EI Shipsey IP Battle M Ernst J Kroha H Roberts S Sparks K Thorndike EH Wang C Artuso M Goldberg M Haupt T Horwitz N Kennett R Moneti GC Playfer S Rozen Y Rubin P 《Physical review D: Particles and fields》1992,46(11):4822-4827
76.
The electronic conductivity of a particular metallic particles/semiconductor system, i.e. Ag particles in cesium-oxide thin film, has been studied. The experimental results show a transition from a polycrystalline semiconductor to metallic behavior as characterized by the conductivity-temperature curve (log bs 1/T), and a five order of magnitude increase in the room temperature value of the conductivity with surface Ag content increasing from an equivalent thickness of 2Å to 20Å. It was observed by TEM that the deposited Ag was mainly in the form of dispersed particles with the particle size varying from 20 to 200Å and their separations varying from hundreds to tens of angstroms over the Ag content range. These results can hardly be explained with the model of direct electron tunneling through the Schottky barrier at the Ag-particle/cesium-oxide interface. A microstructure model with two conduction layers is presented, and an analogy to the hopping conduction mechanism is proposed to explain the electronic conduction behavior. This model predicts that the attenuation length for electronic wavefunctions localized at Ag particles falls in the range 20–50Å. 相似文献
77.
Copper(II)-catalyzed aerobic oxidation of primary alcohols to aldehydes in ionic liquid [bmpy]PF6 总被引:1,自引:0,他引:1
A room-temperature aerobic oxidation of primary alcohols to aldehydes catalyzed by the three-component system acetamido-TEMPO/Cu(ClO(4))(2)/DMAP in the ionic liquid [bmpy]PF(6) has been developed, and the catalysts can be recycled and reused for five runs without any significant loss of catalytic activity. [reaction: see text] 相似文献
78.
A vanadium oxide-modified glassy carbon electrode was simply and conveniently fabricated by casting vanadium tri(isoproxide) oxide (VO(OC3H7)3) and poly(propylene carbonate) (PPC) onto the glassy carbon electrode surface. The electrochemical properties of iodide at the VO(OC3H7)3-PPC film-modified glassy carbon electrode were investigated by cyclic voltammetry, and an anodic peak was observed at approximately +0.71 V (vs. SCE). Based on this, a sensitive and convenient electrochemical method was proposed for the determination of iodide. Flow injection amperometry (FIA) exhibited a good linear relationship with the concentration of iodide in the range of 5 × 10−7 mol L−1 and 1 × 10−3 mol L−1, and the detection limit was 1 × 10−7 mol L−1. Quantitative recovery of iodide in synthetic samples has been obtained and the interferences from different cations and anions have been studied. The method has been successfully applied to the determination of iodide in dry edible seaweed. The concentrations of iodide measured by this method are in good agreement with those obtained by spectrophotometric method. 相似文献
79.
Fan J Gan L Kawaguchi H Sun WY Yu KB Tang WX 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(16):3965-3973
Six noninterpenetrating organic-inorganic hybridized coordination complexes, [Mn(3)(2)(H(2)O)(2)](ClO(4))(2).2 H(2)O (5), [Mn(3)(2)(H(2)O)(2)](NO(3))(2) (6), [Mn(3)(2)(N(3))(2)].2 H(2)O (7), [Cu(3)(2)(H(2)O)(2)](ClO(4))(2) (8), [Mn(4)(2)(H(2)O)(SO(4))].CH(3)OH.5 H(2)O (9) and [Mn(4)(2)](ClO(4))(2) (10) were obtained through self-assembly of novel tripodal ligands, 1,3,5-tris(1-imidazolyl)benzene (3) and 1,3-bis(1-imidazolyl)-5-(imidazol-1-ylmethyl)benzene (4) with the corresponding metal salts, respectively. Their structures were determined by X-ray crystallography. The results of structural analysis of complexes 5, 6, 7, and 8 with rigid ligand 3 indicate that their structures are mainly dependant on the nature of the organic ligand and geometric need of the metal ions, but not influenced greatly by the anions and metal ions. While in complexes 9 and 10, which contain the flexible ligand 4, the counteranion plays an important role in the formation of the frameworks. Entirely different structures of complexes 5 and 10 indicate that the organic ligands greatly affect the structures of assemblies. Furthermore, in complexes 5 and 6, the counteranions located between the cationic layers can be exchanged by other anions. Reversible anion exchanges between complexes 5 and 6 without destruction of the frameworks demonstrate that 5 and 6 can act as cationic layered materials for anion exchange, as determined by IR spectroscopy, elemental analyses, and X-ray powder diffraction. 相似文献
80.
随机变量序列加权和的强收敛性 总被引:12,自引:0,他引:12
本文讨论了一般随机变量序列加权和的强收敛性.作为推论,得到一类鞅差序列加权和的收敛定理和若干经典的独立随机变量序列的强大数定律;已有的若干结论是本文结果的特例. 相似文献