Kinetic spectrophotometric determination of nanogram levels of manganese by use of the salicylaldehyde guanylhydrazone-hydrogen peroxide system

A kinetic method is described for determining trace amounts of manganese(II), based on its catalytic effect on the oxidation of salicylaldehyde guanylhydrazone by hydrogen peroxide. The reaction is followed spectrophotometrically by measuring the rate of change of absorbance at 505 nm. The calibration graph is linear in the range 8-80 mug/l. with a relative error of +/- 1%. The method has been applied to the determination of manganese in various samples.     

Kinetic Spectrophotometric Determination of Manganese by Use of the Salicylaldehyde-Hydrogen Peroxide System

Abstract

A kinetic method is described for determining trace amounts of manganese(II), based on its catalytic effect on the oxidation of salicylaldehyde by hydrogen peroxide. The reaction is followed spectrophotometrically by measuring the rate of change of absorbance at 500 nm. The calibration graph is linear in the range 5–100 ng/ml with a relative error of ± 1.2%. The method has been applied to the determination of manganese in natural water.     

Neutron-activation analysis of manganese in polysulphide materials

A fast non-destructive neutron-activation analysis method has been developed for manganese in polysulphide adhesives. Samples are irradiated for 20 min at a thermal flux of 2 x 10(10) n cm(-2) sec(-1). The net activity in the 0.845-MeV gamma peak of (56)Mn produced by the (n, gamma) reaction in the sample is compared with the activity obtained from a weighed amount of pure manganese irradiated at the same time. Samples containing 2-3% of manganese have been analysed with a relative standard deviation of 2.9%.     

Determination of Trace Manganese by Square‐Wave Stripping Voltammetry

A novel method of determining trace manganese by square‐wave stripping voltammetry with simultaneous plating mercury electrode is described in this paper. Well‐defined stripping peaks of manganese are obtained in H₃BO₄‐NaOH buffer (pH 8.0) and peak currents are in good linear relationship with manganese concentrations in two ranges: from 0.36 nM to 36 nM and from 73 nM to 909 nM. The obtained detection limit is 0.18 nM and relative standard deviation is 2.3% (n=7) under a predeposition time of 90 s. This proposed method has been used for the determination of trace manganese in real plasma samples with satisfiable results and good matching with the results of graphite furnace atomic absorption spectrometry.     

Flow-injection photometric determination of manganese(II) based on its catalysis of the periodate oxidation of N,N'-bis(2-hydroxy-3-sulfopropyl)tolidine

A novel flow-injection spectrophotometric method has been developed for the determination of manganese(II) at sub-nanogram/ml levels. The method is based on its catalytic effect on the oxidation of N,N′-bis(2-hydroxy-3-sulfopropyl)tolidine (HSPT) by periodate. The catalytic effect of manganese(II) was enhanced by the presence of 2,2′-bipyridine as an activator. By monitoring the change in absorbance of the oxidation product of HSPT at 670 nm, manganese(II) ranging 0.02-3.0 ng ml⁻¹ could be determined with the relative standard deviations of less than 2%. The interfering ions were effectively suppressed by the addition of 2,2′-iminodiethanol and citric acid. The proposed method is directly applicable to the determination of manganese in lake and river water samples.     

PLS—分光光度法同时测定铜锌锰

偏最小二乘法(PLS)是用于多组份混合体系同时测定的十分有效的统计学方法。本文将PLS法与光度分析相结合,以5Br-PADAP为显色体系同时计算测定了铜、锌、锰,并应用于铸铝样品的分析,都获得了较满意的结果。还用不相容因子(DF)自检分析结果的可靠性。     

鲁米诺-锰(Ⅱ)-高碘酸钾化学发光体系测定痕量锰的研究

本文提出1种以三乙醇胺作活化剂,基于鲁米诺-锰(Ⅱ)-高碘酸钾化学发光体系高灵敏度、高选择性测定痕量锰的分析方法。检测限达8×10^-6μg/mLMn(Ⅱ)。Mn(Ⅱ)浓度在10^-5～0.1μg/mL范围内呈良好的线性关系。测定1.0×10^-3μg/mLMn(Ⅱ)的相对标准偏差小于±3％。应用于井水及人发样品中锰的测定,结果令人满意。     

Photometric and fluorimetric kinetic determination of manganese by means of the oxidation of sodium 4,8-diamino-1,5-dihydroxyanthraquinone-2,6-disulphonate

Three kinetic methods for the determination of manganese, two of them by photometric monitoring and another by fluorimetric monitoring, based on the oxidation of sodium 4,8-diamino-1,5-dihydroxyanthraquinone-2,6-disulphonate are described. A critical comparative evaluation of both monitoring techniques and their effect on the analytical figures of merit of the methods has been made. Manganese contents between 6.5 and 21.7 ng ml can be determined with relative standard deviation of +/- 3.7%. Under appropriate working conditions, the fluorimetric method can be satisfactorily applied to the determination of manganese in environmental samples of tap water and workroom metallic fumes.     

The determination of manganese by the peroxidisulphate method

The colorimetric determination of manganese according to the periodate method requires a rather long period of heating for the full development of colour, especially in extremely dilute solutions. This fact led the author to investigate the possibilities of the faster peroxidi-sulphate method which for several reasons has been considered as rather unreliable.The extinctions found were compared to those of standard permanganate solutions.The optimum conditions of acidity were fixed. ALTEN AND WEILAND'S statement, that the presence of phosphoric acid prevents the precipitation of manganese dioxide, was verified.The oxidation could be carried out in the presence of chlorides and minute amounts of bromides and iodides if these ions were complexly compounded with mercuric ions. The concentration of the catalysing silver ions can conveniently be kept as low as 10-5 M which will eliminate troubles from silver chloride precipitates.Variation of the concentration of the peroxidisulphate, within wide limits, has no influence on the results.The oxidation may be carried out in the presence of certain amounts of organic matter.The permanganate is stable as long as there is an excess of peroxidisulphate and no reducing compounds are present; the decomposition rate of the peroxidisulphate under the prevailing conditions has been investigated.Amounts of manganese ranging from 100 to 0.1 μmoles (5.5-0.0055 mg) were determined in l00 ml of solution. At the higher manganese concentrations the relative error was about 1 % ; at the lowest concentrations the relative error was larger but the absolute error in no case exceeded 0.01 mmmol.From this investigation it can be concluded that the peroxidisulphate method is at least as accurate as the periodate method. It is more rapid and the fact it can be used in the presence of chlorides and organic matter makes it preferable for several purposes, e.g., for natural waters and soil extracts.     

Simultaneous determination of silicon and aluminium in ferrosilicon by instrumental neutron activation analysis with the aid of an Ac-Be isotopic neutron source

A method has been developed for the accurate determination of silicon and aluminium by instrumental neutron activation analysis with the aid of an²²⁷Ac-Be isotopic neutron source. The samples are pellets made of 4.6 g of ferrosilicon and 0.9 g of a pelletizing agent. Each pellet is irradiated twice at two different fast-to-thermal neutron flux ratios. Each irradiation is followed by two integral mode countings. This allows correction for manganese activities and calculation of the fraction of the aluminium activity induced in silicon and aluminium. The method has been tested with laboratory-prepared synthetic samples as well as commercially certified ferrosilicon. For ferrosilicon containing 75% Si, a relative precision of 0.7% for the results of the silicon concentration has been obtained. For aluminium the relative precision varied from 2 to 7% for concentrations of 3.5 to 1.5%.     

Column preconcentration of trace manganese with the ion pair of 2-nitroso-1-naphthol-4-sulfonic acid tetradecyldimethylbenzyl-ammonium chloride supported on naphthalene and determination by derivative spectrophotometry

A column preconcentration method has been developed for the determination of trace amounts of manganese by preconcentration on 2-nitroso-1-naphthol-4-sulfonic acid (nitroso-S)-tetradecyldimethylbenzylammonium (TDBA) naphthalene as an adsorbent using a simple funnel tipped glass tube. Manganese reacts with nitroso-S to form a water soluble brown colored chelate anion. The chelate anion forms a water insoluble Mn-Nitroso-S-TDBA ion pair on naphthalene packed in a column in the pH range 9.6-10.5 at a flow rate of 1-2 ml/min. The solid mass consisting of manganese complex and naphthalene is dissolved in 5 ml of dimethylformamide (DMF) and the metal determined by second derivative spectrophotometry. The calibration curve is linear in the concentration range 0.25-35.0 micrograms of Mn in 5 ml of the final DMF solution. Eight replicate determinations of 25 micrograms of standard manganese solution give a mean peak height of 4.0 with a correlation coefficient of 0.9995 and relative standard deviation of +/- 1.1%. The sensitivity was calculated to be 0.502(d2 A/d lambda 2)/microgram ml-1 from the slope of the calibration curve. The detection limit was 0.020 microgram ml-1 for manganese at the minimum instrumental settings (signal to noise ratio = 2). Various parameters effecting the method such as the effect of pH, volume of aqueous phase and interference of a number of metal ions on the determination of manganese have been evaluated to optimize the conditions for its determination in standard alloys and biological samples.     

A new chemiluminescence system: MnO(-)(4)-Na(2)CO(3)-KOH and its application in the determination of manganese

A new, fast and simple inorganic chemiluminescence method for the determination of trace amounts of manganese is described. When MnO(-)(4) is injected into 0.40M Na(2)CO(3)-0.70M KOH mixed solution in a reaction cell, the strong chemiluminescence occurs and is recorded. The detection limit is 0.1 ppb Mn and the linear range extends from 0.1 to 10 ppb Mn. A 5-ppb Mn concentration can be determined with a relative standard deviation of 5.6% (15 replicates). The commonly encountered cations do not interfere with the determinations. This method has been successfully applied to the direct determination of manganese in bauxite. The reaction mechanism is also briefly discussed.     

Substoichiometric determination of manganese by neutron-activation analysis

A simple and rapid method for the substoichiometric determination of traces of manganese in various materials by neutron-activation analysis has been developed. After dissolution of the irradiated test sample, manganese(II) carrier is added and subsequently oxidised by peroxodisulphate to the heptavalent state. The permanganate thus formed is finally extracted into chloroform as tetraphenylarsonium permanganate using a substoichiometric amount of tetraphenylarsonium chloride. This single separation step isolates radiochemically pure manganese-56 in the analysis of a relatively simple material in which interfering elements (gold, rhenium, etc.) are absent. When this is not true, a preliminary separation of manganese from the irradiated sample, based on the extraction of manganese diethyldithio-carbamate into chloroform and followed by stripping of the manganese with dilute sulphuric acid, must be used. A simultaneously irradiated standard containing manganese must be treated in exactly the same way as a test sample. In the materials analysed by the new method 10(-5) to 10(-3)% of manganese has been determined.     

Flame atomic absorption spectrometric determination of trace amounts of manganese in alloys and biological samples after preconcentration with the ion pair of 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol and ammonium tetraphenylborate on microcrystalline naphthalene or by column method.

Manganese is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-ammonium tetraphenylborate with microcrystalline naphthalene or by a column method in the pH range 7.5-10.5 from large volumes of aqueous solutions of various samples. After filtration, each solid mass consisting of the manganese complex and naphthalene was dissolved with 5 ml of dimethylformamide and the metal was determined by flame atomic absorption spectrometry. Manganese complex can alternatively be quantitatively adsorbed on ammonium tetraphenylborate-naphthalene adsorbent packed in a column and determined similarly. About 0.1 microgram of manganese can be concentrated in a column from 500 ml of aqueous sample, where its concentration is as low as 0.2 ppb. Eight replicate determinations of 1.0 ppm of manganese gave a mean absorbance of 0.224 with a relative standard deviation of 1.8%. The sensitivity for 1% absorption was 19 ppb. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the trace determination of manganese in various standard samples.     

直读光谱法测定合金工具钢中铬、锰和钼

建立了ARL-4460直读光谱仪对Cr12、Cr12MoV中铬、锰、钼元素的快速检测方法。使用基体铁作为内标元素,测定标准样品中铬、锰、钼元素的相对强度,减少了外界电压不稳对绝对强度稳定性的影响;由于标准样品中基体铁含量不同,为减少内标元素含量的变化对工作曲线相关系数和估计标准差的影响,使用相对含量校正工作曲线。在优化的实验条件下,试样中三种元素的相对标准偏差分别为0.68%、0.79%和1.7%(n=11)。测定结果与化学分析方法测定结果一致,可实现合金工具钢中铬、锰和钼的快速检测。     

Promoting effect of iodide on the hexacyanomanganate(IV)-arsenic(III) redox reaction, for kinetic determination of iodide

The rate of the reaction between hexacyanomanganate(IV) and arsenic(III) in an acid medium is strongly accelerated by iodide. The reaction kinetics indicates that the iodide activity decreases throughout the reaction, probably because manganese(IV) oxidizes iodide to iodate (an inactive form). This behaviour is defined as promotion, rather than catalysis, and this rate-modifying effect has been used to determine iodide by a kinetic method. A linear calibration plot was obtained by a two-point fixed-time procedure. A detection limit of 0.2 ng/ml, a quantification limit of 0.6 ng/ml and relative standard deviations of 5.5 and 13% for the 6.7 and 0.6 ng/ml levels respectively have been found. Positive kinetic interferences from osmium(VIII) and iodate have been observed, and copper(II), silver(I) and mercury(II) inhibit the iodide activity by precipitaton. The method has been applied to determination of iodide in sodium arsenite (reagent grade) and table salt. The method has been validated by recovery experiments.     

Flow-injection spectrophotometry of manganese by catalysis of the periodate oxidation of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)

A sensitive flow-injection spectrophotometric procedure is proposed for the determination of manganese(II), based on its catalytic effect on the oxidation of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) with periodate. By monitoring the change in absorbance of the oxidation product of ABTS at 415 nm, manganese(II) in the range 0.05–1.0 ng ml⁻¹ can be determined with a sampling frequency of 30 h⁻¹. A relative standard deviation (R.S.D.) (n=10) is 1.6% at the 0.5 ng ml⁻¹ level. The proposed method suffers from few interferences and has been successfully applied to the determination of manganese in river, lake and seashore water samples.     

双波长K系数—标准加入吸光光度法同时测定锰和锌

研究应用双波长K系数—标准加入吸光光度法同时测定锰和锌二组分混合物.试验确定了锰和锌测定中K_(Mn)与K_(Zn)的回归方程.对合成试样、人发试样测定,结果满意.     

测定电解锰中微量铁的 FAAS法——采用 EDTA作释放剂

用盐酸溶解试样,加入EDTA等螯合剂作释放剂,通过改变燃烧器高度调整原子蒸气的温度以消除99．8％以上基体锰的干扰,然后用原子吸收光谱法直接测定电解锰中微量的铁,获得了满意的结果。其标准曲线法、标准加入法的结果相吻合,样品加标回收率99．8％,相对标准偏差为3．1％。方法简便快速,适于工厂的快速分析。     

Use of thenoyltrifluoroacetone for the determination of manganese by activation analysis

A new procedure for the substoichiometric extraction of bivalent manganese by thenoyltrifluoroacetone into ethyl acetate has been developed and used in activation analysis. The value of the extraction constant has been found to be 3.1 x 10(-6); the pH range in which the extraction can be performed is 7.8-9.2. The influence of oxalate, citrate, tartrate, fluoride and cyanide ions has been studied. A selective substoichiometric extraction of manganese in the presence of Zr, Hf, Nb, Th, Fe and Sc is possible at pH 8-8.5, tartrate and fluoride being used as masking agents. Copper and cobalt can be screened by ammonia and cyanide respectively. The method has been used for the determination of manganese in biological materials, potassium fluoride and zirconium.