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Jing Zhang Dan Shan Shaolin Mu 《Journal of polymer science. Part A, Polymer chemistry》2007,45(23):5573-5582
A copolymer, poly(aniline‐co‐o‐aminophenol), was prepared chemically by using ammonium peroxydisulfate as an oxidant. The monomer concentration ratio of o‐aminophenol to aniline strongly influences the copolymerization rate and properties of the copolymer. The optimum composition of a mixture for the chemical copolymerization consisted of 0.3 M aniline, 0.021 M o‐aminophenol, 0.42 M ammonium peroxydisulfate, and 2 M H2SO4. The result of cyclic voltammograms in a potential region of ?0.20 to 0.80 V (vs.SCE) indicates that the electrochemical activity of the copolymer prepared under the optimum condition is similar to that of polyaniline in more acid solutions. However, the copolymer still holds the good electrochemical activity until pH 11.0. Therefore, the pH dependence of the electrochemical property of the copolymer is improved, compared with poly(aniline‐co‐o‐aminophenol) prepared electrochemically, and is much better than that of polyaniline. The spectra of IR and 1H NMR confirm that o‐aminophenol units are included in the copolymer chain, which play a key role in extending the usable pH region of the copolymer. The visible spectra of the copolymers show that a high concentration ratio of o‐aminophenol to aniline in a mixture inhibits the chain growth. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5573–5582, 2007 相似文献
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常压催化加氢合成邻氨基苯酚的研究 总被引:1,自引:0,他引:1
用硅溶胶改性的漆原镍催化剂,在常压液相催化条件下,氢化邻硝基苯酚制备邻氨基苯酚的反应过程,可分为诱导期、恒速吸氢阶段、吸氢衰减期3个反应阶段.恒速吸氢阶段的吸氢速率为5×102mol/(kg·min)且与体系的温度无关,诱导期随温度的增加而变短,吸氢衰减期的长短随溶剂量的变化而变化.实验结果表明,邻氨基苯酚的收率在95%左右. 相似文献
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《Electroanalysis》2004,16(16):1359-1365
Electrochemical oxidation of catechols has been studied in the presence of cyanide ion as nucleophile in aqueous solution, by means of cyclic voltammetry and controlled‐potential coulometry. The results indicate that the participation of catechols in the Michael reaction with cyanide ion to form the corresponding o‐dihydroxybenzonitrile. Based on an EC mechanism, the homogeneous rate constants were estimated by comparing the experimental cyclic voltammetric responses with the digital simulated results. 相似文献
7.
D. H. Fremlin R. A. Johnson E. Wajch 《Proceedings of the American Mathematical Society》1996,124(9):2897-2903
A space org/proc/1996-124-09/S0002-9939-96-03488-0/gif-abstract/img2.gif" > Borel multiplies with a space org/proc/1996-124-09/S0002-9939-96-03488-0/gif-abstract/img3.gif" > if each Borel set of org/proc/1996-124-09/S0002-9939-96-03488-0/gif-abstract/img4.gif" > is a member of the org/proc/1996-124-09/S0002-9939-96-03488-0/gif-abstract/img5.gif" >-algebra in org/proc/1996-124-09/S0002-9939-96-03488-0/gif-abstract/img6.gif" > generated by Borel rectangles. We show that a regular space org/proc/1996-124-09/S0002-9939-96-03488-0/gif-abstract/img7.gif" > Borel multiplies with every regular space if and only if org/proc/1996-124-09/S0002-9939-96-03488-0/gif-abstract/img8.gif" > has a countable network. We give an example of a Hausdorff space with a countable network which fails to Borel multiply with any non-separable metric space. In passing, we obtain a characterization of those spaces which Borel multiply with the space of countable ordinals, and an internal necessary and sufficient condition for org/proc/1996-124-09/S0002-9939-96-03488-0/gif-abstract/img9.gif" > to Borel multiply with every metric space.
8.
Helmut Pfitzner und Helmut Schweppe 《Fresenius' Journal of Analytical Chemistry》1974,268(5):337-342
Zusammenfassung In einer früheren Veröffentlichung [4] ist auf die Möglichkeit der chromatographischen Trennung strukturisomerer Metallchelate hingewiesen worden; sie soll hier ausführlicher dargestellt werden. Weiterhin wird die Trennung von 1:2-Mischkomplexen von Azofarbstoffen und von 1:2-Metallkomplex-Mischungen durch Dünnschicht-Chromatographie (DC) an Polyamid beschrieben. Unter bestimmten Voraussetzungen kann durch DC an Kieselgel zwischen 1:2-Metallkomplexfarbstoffen mit Sulfonsäureamid- bzw. Alkylsulfongruppen und solchen ohne diese Substituenten unterschieden werden. Die beschriebenen DC-Methoden ermöglichen bei richtiger Interpretation eine eindeutige Unterscheidung zwischen strukturisomeren Metallkomplexen der 1:1- und 1:2-Reihe, sowie Mischkomplexen und Komplexmischungen vom 1:2-Metall-chelattyp unsulfierter o,oontent/h24864p518475v31/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-Dihydroxyazoverbindungen.Symmetrische o,oontent/h24864p518475v31/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-Dihydroxyazoverbindungen, wie z.B. das 2,2ontent/h24864p518475v31/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-Dihydroxy-5,5ontent/h24864p518475v31/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-dimethyl-azobenzol(7), sind geeignete Komplexbildner für Schwermetallkationen, um diese als farbige Chelate mit Hilfe der DC voneinander zu trennen. Strukturisomere sind wegen der Molekülsymmetrie ausgeschlossen, so daß die Ergebnisse eindeutig sind.
ockquote>1:1 and 1:2 metal chelates of unsulphonated o,oontent/h24864p518475v31/xhuge8242.gif" alt="prime" align="BASELINE" BORDER="0">-dihydroxyazo compounds: A thin-layer chromatographic investigation ockquote>ockquote>In an earlier publication [4] the possibility of the Chromatographic separation of structurally isomeric metal chelates was mentioned; this is dealt with here in more detail. Further the separation of 1:2 mixed complexes from azo dyes and 1:2 metal-complex mixtures by thin-layer chromatography (TLC) on polyamide is described. In certain circumstances it is possible to distinguish between 1:2 metal-complex dyes with sulphonamide or alkylsulphonyl groups and those without these substituents by TLC on silica gel. The TCL methods described allow-when correctly interpreted-an unambiguous distinction between structurally isomeric metal complexes of the 1:1 and 1:2 series, and mixed complexes and mixtures of complexes of the 1:2 metal-chelate type of unsulphonated o,oontent/h24864p518475v31/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-dihydroxyazo compounds.Symmetrical o,oontent/h24864p518475v31/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-dihydroxyazo compounds, such as 2,2ontent/h24864p518475v31/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-dihydroxy-5,5ontent/h24864p518475v31/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-dimethylazobenzene(7), are suitable as complex-formers for heavy-metal ions, allowing the separation of the latter as their coloured chelates with aid of TLC. Structural isomers are excluded because of the molecular symmetry, so that the results are unambiguous. ockquote> 相似文献
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The third generation amperometric biosensor for the determination of hydrogen peroxide (H2O2) has been described. For the fabrication of biosensor, o-aminobenzoic acid (oABA) was first electropolymerized on the surface of platinum (Pt) electrode as an electrostatic repulsion layer to reject interferences. Horseradish peroxidase (HRP) absorbed by nano-scaled particulate gold (nano-Au) was immobilized on the electrode modified with polymerized o-aminobenzoic acid (poABA) with L-cysteine as a linker to prepare a biosensor for the detection of H2O2. Amperometric detection of H2O2 was realized at a potential of +20 mV versus SCE. The resulting biosensor exhibited fast response, excellent reproducibility and sensibility, expanded linear range and low interferences. Temperature and pH dependence and stability of the sensor were investigated. The optimal sensor gave a linear response in the range of 2.99×10^-6 to 3.55×10^-3 mol·L^-1 to H2O2 with a sensibility of 0.0177 A·L^-1·mol^-1 and a detection limit (S/N = 3) of 4.3×10^-7 mol·L^-1. The biosensor demonstrated a 95% response within less than 10 s. 相似文献