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Spectrophotometric Determination of Trace Amounts of Vanadium(Ⅴ) by Means of Its Catalytic Effect on Oxidation of azomethine-H by Bromate

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Rare Metals 2000年第2期19卷 123-130页

作者：高锦章张煊赵保卫杨武赵彦春袁莉王希文康敬万西北师范大学化学研究所甘肃兰州 730070 西北师范大学甘肃兰州 730070

A new selective and sensitive kinetic method for determination of trace amounts of vanadium(Ⅴ) (0.5～40ng/ml) based on its catalytic effect on the oxidation of azomethine H by bromate at pH 4.2 and 25 ℃ was reported and its reaction mechanism was *** reaction was monitored spectrophotometrically by measuring the increase in absorbance of oxidation product of azomethine H at 436 nm after a fixed time ( 5 min ).The detection limit of the method is down to 2.0×10 -10 g/ml and the relative standard deviation (RSD) for 30 ng/ml of V(Ⅴ) is 0.26 % ( n =6). The effect of foreign ions on V(Ⅴ) determination was also discussed,and the method is mostly free from interferences of other *** proposed method was successfully applied to the determination of trace amounts of vanadium in water samples.

关键词： Vanadium(Ⅴ) determination Catalytic spectrophotometry azomethine H Bromate

1,3-Dipolar cycloaddition reaction of two different azomethine ylides to C70

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Chinese Journal of Chemistry 1998年第2期16卷 178-183页

作者：郑大贵李玉良范楼珍李凤英李永舫朱道本 nstitute of Chemistry Chinese Academy of SciencesBeijing 100080ChinaShangrao Teacher's CollegeShangraoJiangzi 334001China nstitute of Chemistry Chinese Academy of SciencesBeijing 100080China

1,3-Dipolar cycloaddition to C70 of an azomethine ylide, which was generated in situ from refluxing a mixture of cyclohexanone and DL-valine in chlorobenzene under N2, afforded a monoadduct and a bisadduct. Even for longer reaction time, however, only monoadduct waa obtained from the reaction of C70 with an azomethine ylide generated from refluxing a mixture of 2-undecanone and 2-aminoisobutyric acid in chlorobenzene under N2. The electrochemical properties of all the products were studied by cyclic voltammetry.

关键词： Fullerenes 1,3-dipolar cycloaddition azomethine electrochemical properties

New azomethine Compounds on the Basis <i>m</i>-Phenylenediamine and Substituted Benzaldehydes Capable of Oxidative Polymerization

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Open Journal of Polymer Chemistry 2018年第2期8卷 34-39页

作者： T. A. Borukaev A. M. Mazloeva R. M. R. M. Otarova Yu. A. Malkanduev A. Kh. Malamatov A. V. Orlov Kabardino-Balkar State University (Named after H. M. Berbekov) Nalchik Russia A.V.Topchiev Institute of Petrochemical Synthesis Russian Academy of Sciences Moscow Russia

Low-temperature condensation of m-phenylene diamine and various aromatic aldehydes (benzaldehyde, m-, o-nitrobenzaldehyde, p-diethylaminobenzaldehyde, o-, p-hydroxybenzaldehyde and 4-hydroxy-3,5-ditert-butylbenzaldehyde) in the ethyl alcohol medium synthesized new azomethine compounds. With the help of spectral methods and elemental analysis, the structure of the azomethine compounds obtained was confirmed. It was founded that irradiation of azomethine compounds with UV light at a wavelength of 300 - 330 nm results in their emission. The luminescent properties of the resulting compounds are due to the presence of chromophore azomethine groups in the molecule structure. In particular, the π-electrons of the azomethine bonds can undergo irradiation to a different energy levels, accompanied by fluorescence. It was shown that synthesized azomethine compounds are capable of oxidative polymerization. Based on azomethine compounds in hydrochloric acid solution synthesized polymers with conjugated bonds, which had low molecular-mass characteristics. It is shown that the oxidative polymerization of azomethines proceeds through a slow (one-electron transfer) and rapid (recombination of the radical cations) stage.

关键词： azomethine Compounds Synthesis Luminescence Oxidative Polymerization

Solution Processable Material Derived from Aromatic Triazole, azomethine and Tris: Preparation and Hole-Buffering Application in Polymer Light-Emitting Diodes

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Journal of Materials Science and Chemical Engineering 2018年第9期6卷 6-28页

作者： Chih-Yang Lin Yun Chen Department of Chemical Engineering National Cheng Kung University Taiwan

This work presents the synthesis of a new hole-buffering material TAZS and its successful application in polymer light-emitting diodes to enhance device performance. The TAZS is composed of aromatic 1,2,4-triazolylcore linked with three trihydroxy tert-butyl terminals via azomethine linkages. The TAZS forms ashomogeneous film deposited by spin-coating process. The HOMO and LUMO levels of TAZS are -5.23 eV and -2.40 eV, respectively, as estimated from cyclic voltammogram. The current density results of hole-only and electron-only devices confirm strong hole-buffering capability of TAZS layer. Multilayer PLEDs with different thickness of TAZS (ITO/PEDOT: PSS/TAZS (x nm)/SY/ETL/LiF/Al) have been successfully fabricated, using spin-coating process to deposit hole-injecting PEDOT: PSS, TAZS, and emissive SY layers. The PLED with 16 nm TAZS reveals the optimal device performance, with maximum luminance and maximum current efficiency of 19,046 cd/m2 and 4.08 cd/A, respectively, surpassing those without TAZS as HBL (8484 cd/m2, 2.13 cd/A). The hole-buffering characteristic of TAZS contributes greatly to improved charges’ recombination ratio and enhanced emission efficiency.

关键词： Hole-Buffering azomethine Aromatic Triazole Tris Polymer Light-Emitting Diodes Spin-Coating

Synthesis, Characterization and Metal Ion Adsorption Studies on Novel Aromatic Poly(azomethine Amide)s Containing Thiourea Groups

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Open Journal of Polymer Chemistry 2014年第1期4卷 1-11页

作者： Lingam Ravikumar Selvaraj Kalaivani Thangaraj Vidhyadevi Arukkani Murugasen Selvaraj Dinesh Kirupha Subramanian Sivanesan Department of Applied Science and Technology Anna University Chennai India Department of Chemistry C.B.M. College Bharathiar University Coimbatore India

A series of novel ladder-type poly(azomethine amide)s (PAMs) were prepared from new azomethine containing carboxylic acid monomer (TCA) with simple aromatic diamines and aromatic diamines with thiourea groups (TDAs) by means of phosphorylation polycondensation reaction. Molecular weights of the polyamides were evaluated viscometrically, and the inherent viscosities were in the range of 0.31 - 0.58 g/dl. These ladder-type polymers were not freely soluble in common organic solvents. Structure of monomers and polymers were confirmed using FT-IR, 1H-NMR and 13C-NMR spectroscopic analysis. Removal of Cu2+ and Cd2+ from aqueous solutions by adsorption onto the polyamides was investigated. The effect of pH, initial metal ion concentrations and contact time were studied in batch experiments. The polyamides were found to be highly effective adsorbents for the removal of Cu2+ and Cd2+ metal ions from aqueous solutions. In a mixture of metal ions, the selectivity order was found to be Pb(II) > Cu(II) > Cr(IV) > Cd(II).

关键词： Polyamide azomethine Phenyl Thiourea Ladder Type Heavy Metal Ion Removal

Synthesis and structure determination of pyrazine-containing macrocyclic polyazomethines

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Chinese Chemical Letters 2010年第10期21卷 1263-1266页

作者： Liang Chun Wu Long Qing Liu Hai Shan Jin Ming Liang Ma Xiao Li Zhao Ke Wen Division of Supramolecular Chemistry and Medicinal Chemistry Key Laboratory of Brain Functional Genomics MOE and Shanghai Key Laboratory of Brain Functional Genomics East China Normal University Shanghai 200062 China Shanghai Key Laboratory of Green Chemistry and Chemical Processes and Department of Chemistry East China Normal University Shanghai 200062 China

Two pyrazine-containing macrocyclic polyazomethines 2 and 3 were synthesized by direct [2 ＋ 2] and [3 ＋ 3] condensation reactions between 2,21-[pyrazine-2,3-diylbis（oxy）]dibenzaldehyde （1） and hydrazine. Both 2 ... 详细信息

关键词： azomethine Macrocycles Schiff base Pyrazine