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1.
1-(2-吡啶偶氮)-2-萘酚-镱二元络合物近红外发光法测定镱   总被引:1,自引:0,他引:1  
齐剑英  孟建新  陈大志  冯德雄 《分析化学》2003,31(12):1473-1475
基于金属指示剂 1 (2 吡啶偶氮 ) 2 萘酚 (PAN)对稀土离子Yb3+ 的近红外发光的敏化作用 ,建立了Yb3+ 的定量分析方法。方法的线性范围为 1 .0× 1 0 - 6 ~ 8.0× 1 0 - 6 mol L,检测下限为 1 .0× 1 0 - 6 mol L ,相对标准偏差为 3 .2 %。该方法适用于在混合稀土样品中选择性地测定Yb3+ 的含量。  相似文献   

2.
《Analytical letters》2012,45(1-2):99-112
Abstract

A spectrophotometric study of the Pd(II) complex of a reagent 2-(5-Bromo-2-Pyridylazo)-5-(diethylamino)-Phenol (5-Br-PADAP) is presented. A violet complex is formed at pH 3.53, and shows maximal absorbance at 585 nm with molar absorptivity of 3.86 × 104 1. mol?1 cm?1. Beer's law is obeyed up to 50 μ of Pd(II). The method offers the advantages of simplicity, high precision, requires no extraction and is very selective, where 5.0 mg Pt(VI) and 0.3 mg Au(III) ions do not interfere.  相似文献   

3.
本文报道了钯与4-(2-吡啶偶氮)间苯二酚(PAR=H_2R,下同)和四苯钟离子形成离子缔合物的化学条件,经氯仿萃取后,建立了一种测定微量钯的萃取光度法。萃取的最佳pH为4.4,络合物的化学式为[(C_6H_5)_4As~+,PdClR~-],其最大吸收峰波长为532nm,表观摩尔吸光系数e_(532)=3.3×10~4L·mol~(-1)·cm~(-1),10mL萃取液中钯量在0~25μg内遵守比耳定律。方法简便,选择性好,用于催化剂中钯的测定,结果满意。  相似文献   

4.
以光度法研究了阳离子型微乳液对显色剂1-(2-吡啶偶氮)-2-萘酚(PAN)的增溶作用,通过测定PAN在阳离子型CTMAB/n-C5H11OH/n-C9H20微乳液中的“胶束位”n和结合常数K,并与相同表面活性剂胶束体系比较,探讨了微乳液对显色剂PAN的增溶作用。  相似文献   

5.
6.
A spectrophotometric method to determine rhenium(IV) at trace level is based on the extraction of Re(IV)-SCN? complex in sulphuric acid media with N,N′-diphenylbenzamidine(DPBA) in presence of a non-ionic surfactant triton X-100 (TX-100) in chloroform. The complex shows maximum absorbance at 435 nm with amolar absorptivity value of 4.24 × 104 L mol?1 cm?1 at an acidity range 3.5-6.5 M H2SO4. The method followed Beer's Law for the system Re(IV)-SCN?(TX-100)-DPBA upto 4.0 μg Re(IV) mL?1. The detection limit of the method is 5 ppb. None of the tested foreign ions, except molybdenum(VI), interfere with the determination of rhenium. The interference due to molybdenum could effectively be removed by prior precipitation with oxine. The effect of various analytical parameters on the extraction of the metal are discussed.  相似文献   

7.
研究了显色剂2-(5-羧基-1,3,4-三氮唑偶氮)-5-二乙氨基苯甲酸(CTZDBA)与钯(Ⅱ)的显色反应。结果表明,Pd(Ⅱ)与CTZDBA生成稳定的1∶2的紫红色配合物,其最大吸收波长为548 nm,配合物的表观摩尔吸光系数为9.32×104L.mol-1.cm-1,Pd(Ⅱ)质量浓度在0.08~0.8 mg/L范围内符合比耳定律。该方法可不经分离直接测定钯碳催化剂和钯纳米碳催化剂中的微量钯,测定结果与原子吸收法(AAS)基本相符。  相似文献   

8.
马同森  张顺利 《分析化学》1999,27(7):825-827
以十二烷基硫酸钠-溴代十六烷基三甲胺(SDS-CIMAB)复合微乳液为介质,对Co(Ⅱ)-1-(2-吡啶偶氮)-2-萘酚的显色反应条件进行了研究.结果表明该体系的λ_(max)=580nm,ε_(580)=3.4×10~4L·mol·cm~(-1),Co(Ⅱ)测定的线性范围为0~2.40mg/L.回收率在96%~103%之间,该法选择性好,用于蔬菜中Co(Ⅱ)含量的测定,得到了满意的结果.  相似文献   

9.
《Analytical letters》2012,45(9):1681-1688
Abstract

Palladium (II) reacts with DPPH in slightly acid medium to form a red colored complex stable in presence of EDTA and extractable into chloroform.

These properties of the Pd(II)-DPPH complex were used for the selective extractive spectrophotometric determination of palladium(II) in presence of several tested cations.  相似文献   

10.
11.
A cloud-point extraction (CPE) process using the nonionic surfactant Triton X-114 to simultaneous extraction and spectrophotometric determination of Zn(II), Co(II) and Ni(II) from aqueous solution using partial least squares (PLS) regression is investigated. The method is based on the color reaction of these cations with 1-(2-pyridylazo)2-naphthol and subsequent micelle-mediated extraction of products. The optimum extraction and reaction conditions such as pH, reagents concentration and effect of time have been studied. Linearity was obeyed in the range 2–150, 5–250 and 2–150 ng mL−1 of Zn(II), Co(II) and Ni(II) respectively. The relative standard error (RSE) for the simultaneous determination of 15 test samples of different concentrations of Zn(II), Co(II) and Ni(II) was 4.38%;, 1.18% and 2.42%, respectively. The total relative standard error (RSEt) for applying the PLS method to 15 synthetic samples in the linear ranges of these metals was 2.36%. The interference effect of some anions and cations was also tested. The method was applied to the simultaneous determination of Zn(II), Co(II) and Ni(II) in water and human urine samples.  相似文献   

12.
本文研究了5-Br-PADAP在酸性介质中质子化,与BrO_3~-和SCN~-形成三元离子缔合物的最佳条件,其表观摩尔吸光系数ε_(540)=4.3×10~4L·mol~(-1)·cm~(-1),缔合物组成比为:5-Br-PADAP:BrO_(3-)SCN~-=1:1·1。提供了测定微量BrO_(3-)的新方法,可应用于化学试剂中微量BrO~(3-)的测定。此外,本文还探讨了反应机理。  相似文献   

13.
用3,5—diBr—PAMB光度法测定微量铑的研究   总被引:4,自引:0,他引:4  
  相似文献   

14.
以α-甲基丙烯酸为功能单体,在氯仿溶剂中,利用传统的分子印迹聚合物制备技术,成功合成了偶氮类分子1-(2-吡啶偶氮)-2-萘酚的印迹聚合物。用红外光谱、紫外光谱等技术对聚合物进行了表征测定,并用平衡结合实验研究了聚合物的吸附特性。  相似文献   

15.
16.
合成了新试剂2 (2 苯并噻唑偶氮) 5 氨基苯甲酸(BTABA),研究了该试剂与钯(Ⅱ)的显色反应。于pH4.5的乙酸盐缓冲溶液中,形成了配位比为Pd∶BTA BA=1∶2的红褐色配合物,其最大吸收波长为603nm,表观摩尔吸光系数ε为6.56×104L·mol-1·cm-1。钯元素含量在0~25.0μg/25mL范围内服从比耳定律。方法应用于Pd C催化剂样品中钯元素含量的测定,结果令人满意。  相似文献   

17.
The complexation reactions between Ni(2+), Co(2+) and Zn(2+) metal ions with PAN in methanol (MeOH), acetonitrile (AN) and dimethyl sulfoxide (DMSO) were studied using a spectrophotometric method. The stability constants of the resulting complexes were determined from computer fitting absorbance mole-ratio data. The results revealed that the stability constants of complexes are varying in order of Ni(2+)相似文献   

18.
近年来,杂环偶氮苯甲酸类显色剂取得了较快的发展。由于氨基取代结构对试剂性能有较大的影响[1],因此本文合成了新显色剂2-(2-噻唑偶氮)-5-二乙氨基苯甲酸,(TAEB)并研究了它与钴的显色反应。  相似文献   

19.
The present work has focused on the modification of multiwalled carbon nanotube with a ligand,l-(2-pyridylazo)-2-naphthol, and its potential application for the development of a new,simple and selective modified glassy carbon electrode for stripping voltammetric determination of Cd(Ⅱ).The analytical curve for Cd(Ⅱ) ions covered the linear range varying from 0.8 up to 220.4μgL-1.The limit of detection was found to be 0.1μgL-1,while the relative standard deviation(RSD) at 50.0μgL-1 was 1.8%(n=5).This modified electrode was successfully applied for determination of Cd(Ⅱ) in some water samples.  相似文献   

20.
The formation of the Tm(III) complex with 1-(2-pyridylazo)-2-naphthol (PAN or HL) in aqueous-methanol mixtures (50 and 75%v/v) was studied by a spectrophotometric method. The equilibrium constant for the complexing reaction and the stability constant of the complex TmL 2+ were calculated. The solvent extraction of Tm(III) byPAN in carbon tetrachloride from aqueous and aqueous-methanol phase was investigated. The extraction equilibrium constants and two-phase stability constants for the TmL 3 and the TmL 3(MeOH)3 complexes were evaluated. It was confirmed that the addition of methanol to the aqueous phase (above 25%v/v) causes a synergistic effect.
Extraktion von Ionen der Seltenerdmetalle mit 1-(2-Pyridylazo)-2-naphthol (PAN), 5. Mitt.: Komplexbildung und Gleichgewichtsverteilung von Thulium (III) mitPAN
Zusammenfassung Die Bildung des Komplexes von Tm(III) mit 1-(2-Pyridylazo)-2-naphthol (PAN oder HL) in Wasser-Methanol Mischungen (50 und 75%v/v) wurde mit einer spektrophotometrischen Methode untersucht. Die Gleichgewichtskonstante für die Reaktion der Komplexbildung und die Stabilitätskonstante des Komplexes TmL 2+ wurden berechnet. Die Extraktion von Tm(III) mittelsPAN in Kohlenstofftetrachlorid aus Wasser oder Wasser-Methanol wurde untersucht. Die Werte der Extraktionsgleichgewichtskonstante sowie der zweiphasigen Beständigkeitskonstante für die Komplexe TmL 3 und TmL 3(MeOH)3 wurden berechnet. Es wurde festgestellt, daß die Zugabe von Methanol zur wäßrigen Phase (25%v/v) einen synergistischen Effekt hat.
  相似文献   

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