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131.
Characterization and application of an electrode modified by mechanically immobilized copper hexacyanoferrate 总被引:1,自引:0,他引:1
A newly modified electrode was prepared by mechanical immobilization of copper hexacyanoferrate (CuHCF) on a graphite electrode.
The modified electrode was characterized by cyclic voltammetric experiments. The effect of different background electrolytes,
pHs and scan rates on the electrochemical behaviour of the electrode has been evaluated. In NH4Cl two reversible redox peaks were observed. The first redox peak corresponding to Cu+/Cu2+ is observed only in this medium. The second redox peak corresponds to the Fe(CN)6
4–/Fe(CN)6
3– couple. Both anodic peaks were used for catalytic oxidation of ascorbic acid. As the anodic current for catalytic oxidation
was proportional to the amount of ascorbic acid, an analytical method was developed for the determination of ascorbic acid
in commercial samples.
Received: 26 May 1998 / Revised: 15 March 1999 / Accepted: 20 March 1999 相似文献
132.
A graphite electrode modified with cobalt hexacyanoferrate by mechanical immobilization was used for amperometric determination of hydrazine. The modified electrode exhibits good catalytic activity for the oxidation of hydrazine at a reduced overpotential with remarkable sensitivity. The modified electrode showed a linear response for hydrazine in the concentration range of 2.0 × 10–5 to 2.8 × 10–4 M. The detection limit was 9.8 × 10–6 M (S/N = 3). The proposed modified electrode was simple, sensitive, rapid, stable and promising. 相似文献
133.
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135.
Madhav S. Mane Ravi S. Balaskar Sandip N. Gavade Pramod N. Pabrekar Murlidhar S. Shingare Dhananjay V. Mane 《中国化学快报》2011,22(9):1039-1042
The regiospecific oxidation of alkyl group of both sterically hindered and unhindered aromatic amine to corresponding carbonyl compound was done in aq. medium by using DDQ. The optimized reaction protocol was found to be most simple, high yielding and novel method for oxidation of alkyl group of aromatic amine in to its carbonyl compound. 相似文献
136.
Said R. Grace Ravi P. Agarwal Martin Bohner Donal O’Regan 《Communications in Nonlinear Science & Numerical Simulation》2009,14(8):3463-3471
We establish some new criteria for the oscillation of second-order nonlinear dynamic equations on a time scale. We study the case of strongly superlinear and the case of strongly sublinear equations subject to various conditions. 相似文献
137.
138.
JPC – Journal of Planar Chromatography – Modern TLC - The normal-phase (NP) and reversed-phase (RP) thin-layer chromatographic separations of aminoglycosides (streptomycin, kanamycin,... 相似文献
139.
K. M. Mathew S. Ravi D. Padmanabhan 《Journal of Radioanalytical and Nuclear Chemistry》2005,265(3):505-506
Summary 4,6-dimethoxy-2-methylsulphonylpyrimidine is a key intermediate for the synthesis of pyrithiobac-sodium, a selective herbicide for cotton plant. 14C labeled pyrithiobac-sodium is required for studying the translocation and metabolism in cotton plants. It was prepared by oxidation of 4,6-dimethoxy-[2-14C]-2-methylmercaptopyrimidine with H5IO6/CrO3 in ethyl acetate at room temperature to give 4,6-dimethoxy-[2-14C]-2-methylsulphonylpyrimidine in high yields. 相似文献
140.
This paper presents a comprehensive review of the work done, during the 1968–2005, in the application of statistical and intelligent techniques to solve the bankruptcy prediction problem faced by banks and firms. The review is categorized by taking the type of technique applied to solve this problem as an important dimension. Accordingly, the papers are grouped in the following families of techniques: (i) statistical techniques, (ii) neural networks, (iii) case-based reasoning, (iv) decision trees, (iv) operational research, (v) evolutionary approaches, (vi) rough set based techniques, (vii) other techniques subsuming fuzzy logic, support vector machine and isotonic separation and (viii) soft computing subsuming seamless hybridization of all the above-mentioned techniques. Of particular significance is that in each paper, the review highlights the source of data sets, financial ratios used, country of origin, time line of study and the comparative performance of techniques in terms of prediction accuracy wherever available. The review also lists some important directions for future research. 相似文献