A photometric and potentiostatic investigation of the complex formation between fluoride and lanthanumalizarin complexone

The composition of the blue complex formed between fluoride and the lanthanum complex of alizarin complexone (H₄A) has been studied by photometric and potentiometric methods with glass and fluoride electrodes. The suggested composition of the complex, La(LaA)₄F₂, is supported by molecular weight estimations. A possible structure of the complex is given.     

The titration of Al with complexone III at a pH 3.5

A titration procedure for Al based on the reaction of Al and complexone III (disodium salt of ethylenediaminetetra-acetic acid, (“versene”) at pH 3.5–4.3 is described. After adding an excess of complexone the excess is back-titrated with thorium nitrate, using alizarin S as an indicator. The reaction is not exactly stoichiometric, but nevertheless quite reproducible, and an about 1% higher factor for Al should be used.     

Synthesis and spectroscopic and catalytic properties of a complex of palladium(II) with alizarin complexone

A 11 complex of Pd(II) with alizarin complexone was synthesized and characterized. This complex displays high catalytic activity in the hydrogenation of nitrobenzene and 1-hexene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 741–743, March, 1991.     

Spectrophotometric determination of fluoride with lanthanum/alizarin complexone by flow injection analysis

Lanthanum/alizarin complexone (1:1) in 70% acetone is used in conjunction with a 500-cm reaction coil at 60°C to determine 0.03–1.2 mg l^?1 fluoride at 24 samples per h. The method is applied to tap-water samples.     

Indirect determination of fluoride in waters with lanthanum alizarin complexone and inductively-coupled plasma emission spectrometry

Fluoride is determined indirectly by measurement of the La II 333.75-nm line in the lanthanum/alizarin complexone/fluoride complex. The ternary complex is extracted into hexanol containing N,N-diethylaniline and the extract is introduced directly into the plasma. Related to water samples, the detection limit (3σ, concentration factor 5) is 0.59 ng ml^?1 fluoride, calibration is linear up to 1.2 μg ml^?1 and the relative standard deviation for 0.04 μg ml^?1 is 2.6%. Alkali, alkali elements and most anions do not interfere. The method is applied in the analysis of river water, coastal seawater and drinking water.     

镓-茜素络合剂极谱络合吸附波的研究

本文报导了镓-茜素络合剂极谱络合吸附波产生的条件及其电极过程机理的研究.     

核固红及稀土核固红极谱行为的研究

在由酸性至碱性的水溶液中均获得了核固红的极谱吸附波, 证实在酸性底液中核固红在汞电极上的吸附符合Frumkin等温式. 对pH由7至11的碱性底液中核固红电还原的ECE机制作了研究, 还获得并研究了在pH11附近, 乙二胺-氯化钾底液中的稀土-核固红体系的极谱络合吸附波。     

槲皮素伏安行为及其稀土络合物极谱催化氢波研究

在乙醇量小于5％的水溶液中，于pH1.5至4.5，4.2至9.5分别得到槲皮素的两个还原波，均为羰基两电子还原．前者为其分子的强吸附波，后者为一价阴离子的波．在pH6.1附近的醋酸盐缓冲底液中，可获得槲皮素与Tb（Ⅲ）、Dy（Ⅲ）、Ho（Ⅲ）、Er（Ⅲ）、Tm（Ⅲ）、Yb（Ⅲ）、Lu（Ⅲ）和Y（Ⅲ）等重稀土离子络合物的双重表面催化氢波．络合物被诱导吸附，组成为（REL_2）L_吸．Sc（Ⅲ）与槲皮素形成单一表面催化氢波，其组成为（ScL）L_吸．     

茜素修饰碳糊电极吸附伏安法测定痕量铜

报道了采用茜素修饰碳糊电极测定痕量铜的阳极溶出伏安法。在浓度为0 .1 mol/L 的 HAc- Na Ac缓冲溶液 (p H4.5)中 ,于 +0 .1 0 V处富集 ,- 0 .30 V还原后再进行阳极化扫描 ,于 - 0 .0 5V处获得一灵敏的铜的溶出峰 ,二次导数峰电流与铜浓度在 1 .6× 1 0 -9mol/L～ 4.7× 1 0 -7mol/L范围内呈线性关系 ,检出限达 8.0× 1 0 -10 mol/L。同时 ,对电极反应机理进行了讨论。方法应用于锌合金中铜的测定。     

Gravimetric estimation of uranium as oxinate using complexone as a masking agent

Summary The scope of complexone (disodium salt of ethylenediamine tetraacetic acid) as masking agent has been further extended. Uranium is estimated as oxinate in presence of Th, R. E. and Zr. Uranium is also estimated in presence of 100 mg. of Th, and 30 mg. of R. E. respectively in presence of 100 mg. of P₂O₅. Uranium has been separated from V₂O₅ by reducing the latter in mild acid solution with complexone itself.     

茜素绿的电还原

本文用普通极谱、脉冲极谱、循环伏安等方法研究了茜素绿的电还原。在Britton-Ro-binson缓冲溶液中,随pH不同,茜素绿先后共可产生4个极谱波。其中第一、第四波为吸附波。第一、二波之和相当于从氧化态到中间态的还原;第三波相当于从中间态到还原态的还原。根据一系列实验结果确定了各波的性质,提出一带有岐化反应的电还原机理,并测定了茜素绿的离解常数。     

Adsorption voltammetry of the scandium-alizarin red S complex onto a carbon paste electrode

For the first time, a new method is described for the determination of scandium based on the cathodic adsorptive stripping of the scandium-alizarin red S complex onto a carbon paste electrode. The second-order derivative linear scan voltammograms of the complex are recorded by use of model JP-303 polarographic analyzer from 0.0 to -1.0 V (versus SCE). Optimum conditions are found to be: an acetic acid (0.36 mol l(-1))-potassium biphthalate (0.064 mol l(-1)) buffer solution (pH 4.0) containing 2.0x10(-5) mol l(-1) alizarin red S, a preconcentration potential of 0.0 V, a preconcentration time of 60 s, a rest time of 10 s and a scan rate of 100 mV s(-1). The results show that the complex can be adsorbed on the surface of a carbon paste electrode, yielding one peak at -0.58 V, corresponding to the reduction of alizarin red S in the complex at the electrode. The detection limit is found to be 6.0x10(-10) mol l(-1) for 3 min of preconcentration time. The linear range is 1.0x10(-9) to 4.0x10(-7) mol l(-1). Application of the procedure to the determination of scandium in the ore samples gave good results.     

Adsorptive stripping voltammetric determination of vanadium as chloranilic acid complex

Traces of vanadium(V) can be determined up to 21 ng/l by adsorptive stripping voltammetry using 2,5-dichloro-1,4-dihydroxy-3,6-benzoquinone (chloranilic acid) as complex forming reagent. The complex is stable in a 0.1 mol/l acetate buffer (pH 4.6) solution and adsorbed at the electrode surface in a potential range between –150 mV and –400 mV. The adsorption process is solved by alternating current (ac) voltammetric measurements. The method is applied to different real samples.     

锌(Ⅱ)-茜素紫络合物的极谱行为及应用

用线性扫描示波极谱法研究了锌 ( ) -茜素紫络合物的伏安行为 ,发现在含有 0 .1 mol/L KCl,p H=9.96的 Britton- Robinson缓冲溶液中锌 ( ) -茜素紫络合物产生一灵敏的极谱吸附波 ,其峰电位为 - 1 .2 7V( vs.SCE) ,峰电流与锌 ( )的浓度在 8× 1 0 - 8～ 2× 1 0 - 6 mol/L的范围内呈线性关系 ,检出限为 5× 1 0 - 8mol/L。研究了电极反应机理 ,并用建立的方法成功地测定了发样中的锌     

Adsorption voltammetry of the copper(II) 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol complex

The voltammetric determination of copper(II), based on adsorptive accumulation of the Cu(II)-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (S-Br-PADAP) complex on a hanging mercury drop electrode, is reported. The complex can be accumulated at the electrode at constant potential in 0.1M ammonium nitrate/ammonia buffer solution, and its reduction wave observed by scanning the potential in the negative direction, in the differential pulse mode. The calibration graph for copper is linear over the range 0.05-0.5muM, with accumulation for 5 min at -0.20 V. The adsorption of the complex is discussed and compared with that of copper complexes with several other pyridylazo derivatives.     

A selective procedure for the gravimetric estimation of uranium as oxinate using complexone as masking agent

The existing method. for the estimation of U in hexavalent condition as oxinate has been slightly modified and the scope of complexone (disodium salt of ethylenediaminetetraacetic acid) as a masking agent to develop a selective method for its estimation in presence of interfering elements has been studied. It has been found that at pH ranges from 5-9 complexone exerts no influence on the complete precipitation of uranium and that uranium can be quantitatively separated from Th, R.E., Zr, Fe⁺³, Al, Cu, Co, Ni, Zn, Cd, Pb, Bi, Mn and P₂O₅ by precipitation with oxine in a solution buffered with acetic acid and ammonium acetate (pH approximately 5.3) and also from V₂O₅, MoO₃ and WO₃ in ammoniacal medium (pH approximately 8.4).     

Anwendung des Alizarins und seiner Derivate zur Molybdänbestimmung

Zusammenfassung Eine Methode für die Bestimmung des Molybdäns mit Alizarinkomplexon wurde entwickelt und mit anderen Alizarin-Derivaten verglichen. In Alkohol-Wasser bildet sich bei pH 5 bei Alizarinkomplexon überschuß ein Komplex im Verhältnis 11, der bei 480 nm absorbiert. Der molare Extinktionskoeffizient ist 4,689 undK _f = 2,51 · 10⁵. Die Methode wurde zur Analyse einer Stahlprobe angewendet, wobei die störenden Elemente papierchromatographisch abgetrennt wurden.

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Use of alizarin and its derivatives for the determination of molybdenum

Summary A method has been developed for the determination of molybdenum with alizarin complexone and compared with other alizarin derivatives. In alcohol-water, and at pH = 5, and an excess of alizarin complexone, there is produced a complex, in the ratio of 11, which absorbs at 480 nm. The molar extinction coefficient is 4.689 and the K_f = 2,51 · 10⁵. The method was employed in the analysis of a specimen of a steel, whereby the interfering elements were separated off by paper Chromatographic means.

     

Trace Determination of Zirconium（Ⅳ） by Anodic Adsorptive Voltammetry at a Carbon Paste Electrode

A new sensitive adsorptive voltammetric method was described for the determination ofzirconium at a carbon paste electrode (CPE) in the presence of alizarin complexone (ALC).Optimal analytical conditions are: 1.0~ l0“6 or 5.0x l0“7 mol/L ALC, 0.20 mol/L HAC-NaAc (pH4.3), accumulation for 60 s at 0 V (vs. SCE), and linear scanning from 0 V to 1.0 V at 250 mV/s.The peak potential of the complex is at 0.81 V. By using a model JP-303 polarographic analyzer,2.0~ l0l~ mol/L (S/N=3) zirconium can be detected with a 90 s accumulation, when the 2nd-orderderivative linear sweep technique is used, and the linear range is 6.0~ 10l~-2.0~ l0s mol/L (5.0~ l07mol/L ALC) and 2.0~108-2.0~ l07 mol/L (1.0~ 10.6 mol/L ALC), respectively. The developedmethod was applied to the determination of trace zirconium in the ore samples with satisfactoryresults.     

茜素红S-硼酸体系对单糖的双光谱识别

利用硼酸与茜素红S和糖中的邻二羟基可逆结合的特点,以硼酸为中介运用竞争结合作用机理构建单糖分析法.在pH7.4的KH2PO4-NaOH缓冲溶液中,茜素红S作为指示剂与硼酸结合生成ARS-BA配合物,其结合常数为5.09×102L/mol.糖与指示剂ARS竞争结合硼酸使指示剂游离出来,产生明显的颜色变化,据此建立糖的识别方法.考察了D-葡萄糖、D-山梨醇、D-半乳糖、D-甘露糖、D-果糖、D-阿拉伯糖和L-阿拉伯糖对上述ARS-BA体系光谱的影响.结果显示:该体系对D-山梨醇和D-果糖有较好的光谱响应,其光谱变化灵敏度依D-山梨醇＞D-果糖＞D-阿拉伯糖～D-半乳糖＞D-葡萄糖＞D-甘露糖＞L-阿拉伯糖之序.     

Alizarin-modified sulfonate carbon nanoparticles in vanadium sensing

The adsorption processes of alizarin onto hydrophilic carbon nanoparticles (Emperor 2000?) are investigated. The significant increase in voltammetric responses for pre-adsorbed alizarin compared with those for solution confirms high affinity of alizarin to carbon nanoparticles (possibly due to π–π stacking interaction between aromatic rings of alizarin and surface-sulfonated carbon nanoparticles). To obtain the optimum of adsorption conditions, the effects of pH, agitation rate, and adsorption time are investigated. Under square wave voltammetry conditions, the peak current for the reduction of alizarin shows a linear relationship with concentration in the range from 2.0 to 10.0 nM. The limit of detection is estimated 5.8?×?10^?9 mol L^?1. Next, alizarin is applied as a receptor for sensing of trace vanadium in acetate buffer pH 5. Linear calibration curves are obtained for vanadium in the range of 1.0?×?10^?6 to 1.0?×?10^?4 mol L^?1 and the limit of detection is estimated 9.6?×?10^?8 mol L^?1. Determination of vanadium in real samples such as sea and tap water is demonstrated.