马兜铃酸A的伏安及示波极谱行为研究

马兜铃酸A(简称从)为关木通、朱砂莲等多种常用中药的主要成分。马兜铃酸A具有抗癌、抗感染、抗早孕及增强吞噬细胞活性等方面的药理作用,可作为含量测定指标,其对肝、肾的毒性为有效剂量的1000倍,在医药上它已得到广泛的药理应用。鉴于生物体内的氧化还原过程和电化学过程都具有电子传递的共性,研究马兜铃酸A的电化学性能具有特殊重要的意义。     

葛根素的循环伏安测定及其电化学行为研究

在0.02 mol/L NH4Cl-NH3.H2O(pH8.0)的底液中,采用循环伏安法测定葛根素,得到一良好的氧化峰,峰电位Ep=+0.57V,峰电流Ip与葛根素的浓度在1.046×10-7～5.767×10-5mol/L范围内成线性关系,相关系数r为0.9989,检出限为1.046×10-7mol/L.测定葛根中葛根素的含量,平均回收率在99.8%.并且研究了葛根素在玻碳电极上的电化学行为,结果表明葛根素的电极过程具有吸附性和不可逆性.     

N,N′- 双(3-羧基水杨醛叉缩胺乙基)草酰胺均双核铜(II),镍(II)配合物合成和性能研究

近来发现草酰胺具有多原子成桥功能, Kahn和廖代正等人 [1,2]设计合成一些对称和不对称草酰胺桥联的双核及多核配合物,并对其性质进行研究。本文报导 N,N′-双（ 3-羧基水杨醛叉缩胺乙基 )草酰胺配体及其铜 ?、镍 ?均双核配合物的合成和表征,及铜双核配合物的电化学性能研究。 1实验部分 1.1合 成 草酰二（乙二胺）及 3-羧基水杨醛均按文献方法合成 [3,4]。 1.1.1配体的合成 N,N′-双 (3-羧基水杨醛叉缩胺乙基 )草酰胺的合成将 256.7mg草酰二（乙二胺）溶于少量水中 ,加入含有 490.2mg 3-羧基水杨醛的乙醇溶液 10mL,搅拌回流半小时…     

对-氢醌金属配合物：合成，结构及电化学性质

A new Chromium(Ⅲ) complex, [Cr(Hcah)(H₂O)₂]·2H₂O, where H₄cah=2-[N,N-bis(carboxymethyl)aminome-thyl] hydroquinone (H₄cah), has been synthesized and characterized using X-ray diffraction single crystal structure determination, IR and elemental analysis. The complex belongs monoclinic, space group P2₁/c, with a=0.792 05(4) nm, b=1.008 63(6) nm, c=1.920 40(10) nm, β=93.069(4)°, V=1.531 98(14) nm³, and Z=4. The cyclic voltametric analysis shows that the electron transfer in the electrode reaction is irreversible for Cr(Ⅲ)/Cr₂O₇^2- and Cr(Ⅲ)/Cr(Ⅱ) redox couples while reversible for process of interchange from p-Hydroquinone to p-semiquinones. CCDC: 666208.     

浓碱溶液中生成高铁酸盐的玻碳电极循环伏安法表征(英文)

用玻碳电极研究了与Fe(Ⅵ)／Fe(Ⅲ)电对氧化还原有关的循环伏安曲线.所研究的体系是13mol·L-1NaOH中浓度范围分别为0.015～0.06mol·L-1的Na2FeO4和0.01～0.025mol·L-1的NaFeO2溶液。另一类研究体系是胶体石墨分别与固体K2FeO4、固体KFeO2组成的混合物,将这些混合物粘附于玻碳电极表面后在13mol·L-1KOH中进行循环伏安曲线的测定。结果证明了峰电位在0.7～1.0V的阳极电流峰与峰电位在0.15～0.2V(均相对于13mol·L-1NaOH或13mol·L-1KOH溶液中的Hg／HgO参比电极)的阴极电流峰,分别与高铁酸盐的生成与还原相对应。确定了将高铁酸盐的阳极生成电流峰与阳极析氧电流峰区别开来的条件。     

The surface catalytic mechanism: a comparative study with square-wave and staircase cyclic voltammetry

A pseudo-first-order catalytic mechanism in which both reactant and product of a redox reaction are strongly immobilized on an electrode surface is theoretically analysed under conditions of square-wave (SWV) and staircase cyclic voltammetry (SCV). A mathematical procedure is developed under diffusionless conditions. The relationships between the properties of the voltammetric response and both the kinetic parameters of the redox reaction and the parameters of the excitation signal are studied. The phenomenon of the quasi-reversible maximum is discussed. A comparative study between SWV and SCV is presented and the limitations and advantages of both techniques, from analytical and kinetic points of view, are discussed. The theoretical predictions are experimentally confirmed by the redox reaction of azobenzene in the presence of hydrogen peroxide as an oxidizing agent. Electronic Publication     

普鲁士蓝薄膜的电积法制备及其化学组成

在金属和石墨基底电极上用恒电位沉积法制备出普鲁士蓝(PB)薄膜,研究了影响膜生长的多种因素;观察到PB膜的电化学活性。用红外光谱及电子能谱对膜的化学组成作了分析,结果表明,最初制备的膜为不溶性PB:Fe_4[Fe(CN)_6]_3,在含K~+的电解质溶液中经电化学反应后膜部分转变为可溶性PB:KFeFe(CN)_6,由此确定了PB膜的电化学反应式。     

吡虫啉电化学性能研究

应用循环伏安法研究了吡虫啉（IDP）在玻碳电极的电化学行为.结果表明：IDP的还原反应是不可逆的,且受扩散控制,电子转移数4,扩散系数DR2.44×10-6cm2.s-1,反应活化能Ed9.33 kJ.mol-1.     

纳米TiO2电极在不同介质中的电化学行为

纳米电极;电催化;纳米TiO2电极在不同介质中的电化学行为;循环伏安法;循环方波伏安法     

肉桂醛存在下的吡咯电解聚合

在肉桂醛存在下,将吡咯用电解聚合法分别在玻璃和导电胶片表面上形成薄膜,并用循环伏安法研究了它们的电位-电流特性,发现在相同的实验条件下,在不同的基质表面上所得到的聚合物具有不同形状的图谱,表明用电解聚合法构成复合材料时,基质表面的组成与结构是决定薄膜性质的重要因素之一。     

Cyclic Voltammetric and Morphological Studies of Polyaniline

Cyclic voltammograms and morphology of polyaniline were studied under various synthetic conditions and in various protonic acid media. The effect of protonic acid is not remarkable. The cyclic voltammogram and morphology depend on the synthetic conditions. The anodic peak potential at 0.14 V versus SCE in the cyclic voltammogram is pH independent. The anodic peak potential at 0.7 V versus SCE (pH=1) is pH dependent. By comparing the range of pH and oxidation potential of the conductive form, we propose that the conductive species which exists in the potential range between the first and the second peak in cyclic voltammogram is the radical cation.     

Electrochemical reduction of diazepam

The reduction of 7-chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepine-2-one at the dropping mercury electrode has been investigated. The process is diffusion controlled; furthermore, the reduction wave enables the quantitative determination of the drug both in acid and basic media. The reagent captures two electrons and two hydrogen ions. A disproportionation reaction of the hydrazo-compound takes place, and amines are the final reduction products.     

Electrochemical polymerization of fullerene C60

Cyclic voltammetry data show that fullerene C₆₀ films on the Pt electrode surface in MeCN are electropolymerized to form polymeric C₆₀. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 863–865, April, 1997.     

Voltammetric Behavior of 1,4‐Dimethoxypillar[m]arene[n]quinones

The electrochemical properties of a series of 1,4‐dimethoxypillar[m]arene[n]quinones (DMP[m]A[n]Qs) and the interactions between individual quinone units have been investigated on glassy carbon electrode in acetonitrile. All the quinone units showed relative electron uptake behavior except 1,4‐dimethoxypillar[5]quinones (DMP[5]Q). The results have shown that the electrochemical behavior of the DMP[m]A[n]Qs is comparatively different from that of their related linear quinone analogues. The resultant properties were attributed to the close proximity of redox‐active sites as well as the delocalization of electrons on the aromatic rings. Another aspect to be considered responsible for their electronic properties was suggested to be the electrostatic repulsions between adjacent quinone units in these complex structures. Current studies provide a better understanding on the voltammetric behavior of pillararene derivatives with different numbers of quinone units as well as their future scope in certain future electrochemical applications.     

Synthesis of redox-active biscalix[4]quinones and their electrochemical properties

Biscalix[4]arenes, 7 and 8, have been synthesized by a one-pot coupling method and a stepwise approach, respectively. One-pot reaction in a pressurized vessel resulted in the symmetric biscalix[4]arene 7 in high yield. Oxidation of compounds 7 and 8 by Tl(CO₂CF₃)₃ in CF₃COOH yielded biscalix[4]quinones, 9 and 10, respectively. Preliminary electrochemical studies by cyclic voltammetry of 9 and 10 show significant changes of their voltammograms upon addition of Na⁺.     

C60Co(Pph3)2的合成和表征

The fullerene complexe C₆₀Co(Pph₃)₂ has been prepared by the reaction of C₆₀ with CoCl₂(Pph₃)₂ under a nitrogen atmosphere and refluxing， and characterized by elemental analyses， FT-IR， XPS， NMR， which appove that C₆₀ coordinates to Co(Pph₃)₂ group in σ-π pattern and the electron is super conjugate over whole molecule. The result of redox property study show that the reduction potentiel of C₆₀Co(Pph₃)₂ is more negative than that of C₆₀， the reason may be the π electron dentensity of C₆₀ in C₆₀Co(Pph₃)₂ increases， which lead to it′s electron affinity decreasing. The thermostability experiment indicates that the oxidation decomposition temperature of C₆₀Co(Pph₃)₂ is lower than that of pure C₆₀.     

阿苯达唑的微波-循环伏安法测定

以玻碳电极为工作电极,在微波作用下采用循环伏安法研究了阿苯达唑的电化学特性,结果表明微波可以增大阿苯达唑的氧化峰电流,据此建立了一种新型检测阿苯达唑的电化学方法。在优化实验条件下,无微波作用时,响应电流与阿苯达唑的浓度在4.0×10-5~1.0×10-3mol/L范围内呈线性关系,线性方程为Ip(μA)=8.303 6c(mmol/L)+0.727 1(r=0.999 3,n=7),检出限为1.78×10-5mol/L;在80 W微波作用下,阿苯达唑的峰电流增大近1倍,响应电流与阿苯达唑的浓度在2.0×10-5~1.0×10-3mol/L范围内呈线性关系,线性方程为Ip(μA)=15.41c(mmol/L)+1.435 9(r=0.998 9,n=8),检出限为1.01×10-5mol/L。研究表明,微波-循环伏安法测定阿苯达唑具有较高的选择性和灵敏度,且样品处理简单快速,用于阿苯达唑片的测定,结果满意。     

多硫二硫烯铜配合物(n-Bu4N)[Cu(cddt)2]和(Ph4P)[Cu(cddt)2]的合成、表征及其结构

Two copper complexes with a new multi-sulfur 1,2-dithiolene ligand, C[Cu(cddt)₂] (C=tetrabutylammoni-um, n-Bu₄N⁺; tetraphenylphosphonium, Ph₄P⁺; cddt = 4a, 6, 7, 7a-5H-cyclopenta[b]-1,4-dithiin-2,3 dithi-olate) have been synthesized and characterized by electrochemical studies, IR, EA, etc. The structure of (Ph₄P)[Cu(cddt)₂] was determined by single crystal X-ray analysis. The complex was crystallized in the triclinic, space group P1 with the cell dimensions a=10.460(2)?, b=13.000(3)?,c=16.270(3)?, α=86.68(3)°,β= 71.92(3)°,γ=66.66(3)° and Z=2. R₁=0.0548, wR₂=0.1358 for 6786 independent reflections. The four S atoms surround the Cu atom [CuS₄] core is a square-planar environment.     

Cathodic Stripping Voltammetry Of Cerium

Abstract

The experimental conditions for the accumulation of cerium as insoluble Ce₃(PO₄)₄ on a platinum indicator electrode were studied. The determination of cerium down to 0.01% in oxides of other lanthanides is described.     

电化学测定谷胱甘肽方法的研究

采用循环伏安扫描的方法, 促进谷胱甘肽与邻苯醌亲核加成产物在玻碳电极表面的生成和富集. 在此后的差分脉冲分析中, 邻苯醌的还原峰与谷胱甘肽-邻苯醌加合物的还原峰完全分开, 实现了谷胱甘肽的单独测定. 研究了溶液pH值, 邻苯二酚浓度及循环伏安扫描条件对谷胱甘肽测定的影响. 在优化的条件下, 测定谷胱甘肽的检测限为0.05 µmol/L, 线性范围是0.1 µmol/L～1.7 µmol/L, 同时抗坏血酸, 甘氨酸, L-酪氨酸, L-赖氨酸和半胱氨酸对测定没有干扰. 此电化学测定谷胱甘肽方法选择性好、灵敏度高.