痕量分析中的流动注射法

本文讨论了流动注射分析(FIA)技术在痕量分析中的突出优点,阐述了该技术在痕量分析领域中的应用。文中介绍的流动注射原子光谱分析、流动注射在线分离和浓集技术、流动注射催化动力学方法以及流动注射化学发光、生物发光分析等在痕量分析中具有广阔的发展前景。     

光泽精与钨（Ⅲ）的流动注射—胶束增敏化学发光反应

采用了Jones柱在线还原钨（Ⅵ）为钨（Ⅲ）,详细研究了钨（Ⅲ）与光泽精的化学发光反应,加入乳化剂OP能明显提高发光的信噪比,基于此建立了痕量钨的流动注射化学发光分析法。该法线性范围为1×10     

流动注射化学发光法测定痕量抗坏血酸

流动注射化学发光法测定痕量抗坏血酸沈爱宝徐秉洳季美娟吴锦明（南通医学院，南通，２２６００１）（南通师范专科学校，南通，２２６００７）抗坏血酸又称维生素Ｃ（Ｖｃ），是人体不可缺少的一种营养物质．本文报道用氯化血红素－鲁米诺－过氧化氢化学发光新体系测Ｖ...     

流动注射-化学发光法测定地质样品中的痕量钴（Ⅱ）

1 引言 化学发光分析具有灵敏度高、线性范围宽、仪器简单价廉等优点,已被用于免疫分析、水样分析和其它简单样品中无机组分的分析.但由于选择性较差,目前还很少见到利用该方法测定地质样品中痕量元素的报道.我们详细研究了流动注射-化学发光法测定地质样品中痕量钴的条件,实现了化学发光法测定地质样品中的痕量钴.     

流动注射化学发光法测定痕量硫

基于硫离子对鲁米诺－过氧化氢化学发光反应的增敏作用,建立了测定痕量硫的流动注射化学发光反应的增敏作用,建立了测定痕量硫的流动注射化学发光的新方法。该方法的线性范围为２．０×１０－９～８．０×１０－７ｇ／ｍＬ,检出限为５．６×１０－１０ｇ／ｍＬ,相对标准偏差小于５％（１．０×１０－７ｇ／ｍＬＳ２－,ｎ＝１１）。方法简单,快速,灵敏,已用于环境水样中痕量硫的测定。     

无机还原剂与光泽精化学发光反应的研究：Ⅱ.钼（Ⅲ）—光泽精化学发光反应

本利用流动注射技术研究了Ｊｏｎｅｓ柱产生的钼（Ⅲ）与光泽精的化学发光反应。建立了痕量相的流动注射化学发光分析法。方法的检出限是１×１０＾－＾１＾１ｇ／ｍｌ；校准曲线的线性范围是１×１０＾－＾１＾０－１×１０＾－＾６ｇ／ｍｌ；相对标准偏差为２．０％（１×１０＾－＾７ｇ／ｍｌ钼，ｎ＝１１）。此法已用于水样的分析，结果令人满意。本还进行了反应机理的探讨。     

流动注射化学发光分析研究与应用进展

评述近年来流动注射化学发光分析法的最新进展。总结了流动注射化学发光中重要的化学发光试剂及其相应的新发光体系,概述了流动注射化学发光分析与特定的检测技术、分离技术结合形成的分析体系及其应用。     

无机偶合反应流动注射化学发光分析法测定痕量汞──K_4Fe(CN)_6-Luminol体系

本文将Hg（Ⅱ）催化K4Fe（CN）6分解的反应与鲁米诺同Cu（CN）的化学发光反应相偶合，采用流动注射分析技术，实现了痕量汞的测定。方法的检出限为DL＝2．2×10-7g／L，测定汞的线性范围为8×10－7～4×10－5g／L，对8μg／L汞进行测定，相对标准偏差为3．4％。用于环境水中痕量汞的测定结果很好。     

表面活性剂增强铈(Ⅳ)-碘化学发光体系测定尿液中痕量碘

1引言 碘是人体必需的微量元素,正常人尿液中尿碘含量为100～200μg／L,目前尿碘测定方法主要采用催化光度法。本实验对铈（Ⅳ）氧化碘离子反应进行了研究,发现在酸性溶液中,在吐温40的存在下,铈（Ⅳ）氧化碘离子产生较强的化学发光,建立了铈（Ⅳ）-吐温40-碘（I^-）化学发光新体系,并探讨了其发光机理。基于该发光体系,建立了流动注射化学发光测定碘化学发光新方法,该法可用于尿液中痕量碘的测定,结果令人满意。     

流动注射—化学发光分析测定矿石中痕量铌

利用铌对鲁米诺－Ｈ２Ｏ２－Ｋ３Ｆｅ（ＣＮ）６化学发光体系的抑制作用，建立了痕量Ｎｂ（Ⅴ）的流动注射－化学发光测定法。方法的检出限是２．３ｎｇ／ｍＬＮｂ（Ｖ）．线性范围为０．０１－１μｇ／ｍｌＮｂ（Ｖ），测定的相对标准偏差为３．０％（０．０１μｇ／ｍＬＮｂ（Ｖ）（ｎ＝１１），方法已应用于矿石中Ｎｂ的测定。     

Fast simultaneous determination of niobium and tantalum by Kalman Filter analysis with flow injection chemiluminescence method.

A fast and highly efficient Kalman Filter analysis-flow injection chemiluminescence (FI-CL) method was developed to simultaneously determine trace amounts of niobium and tantalum in geological samples. The method, without the boring process of separation and dear instruments, is suitable for field scene analysis. The mixed chemiluminescence kinetic curve was analyzed by a Kalman Filter (KF) in this method to realize the simultaneous determination of niobium and tantalum. Possible interference elements in the determination were investigated. Under the selected conditions, the detection limits (3sigma, n = 11) of niobium(V) and tantalum(V) were 2.1 x 10(-3) microg g(-1) and 4.0 x 10(-3) microg g(-1), respectively, and the relative standard deviations were 4.9% and 3.3% (n = 9). The method was applied to the determination of niobium and tantalum in geological samples with satisfactory results.     

Analytical applications of infra-red spectroscopy : The behaviour of the oxinates of niobium,tantalum and associated elements

The behaviour of the oxinates of niobium, tantalum and associated metals in the infra-red region was studied and a method developed for the determination of niobium and tantalum. Vanadium caused no interference, but other heavy metals, such as molybdenum, manganese and cobalt, which interfered were removed by preliminary treatment when the method was applied to the determination of niobium and tantalum in steels.     

Colorimetric determination of niobium in titanium alloys

There is need for a method for the determination of niobium in titanium alloys, since niobium-titanium alloys are becoming increasingly important. The determination of niobium in this type of alloy is an extremely difficult matter. Many approaches were tried before the problem was solved. In the method proposed in this paper the sample is dissolved in a mixture of hydrofluoric and nitric acids, the solution evaporated to a small volume, and boric acid added. Two tannic acid separations are then made to separate the niobium from the bulk of the titanium. The niobium, is determined colorimetrically by the thiocyanate method using a water-acetone medium. A study was made of the possible interference of elements that might be present in titanium alloys. It was found that the presence of tantalum causes two opposing tendencies. Tantalum can cause high results for niobium because it forms a complex with thiocyanate which is visually colorless but shows some absorption. Tantalum can cause low results for niobium by hindering the development of the niobium color. The resultant effect of the tantalum depends upon the amount of tantalum present, the amount of niobium present and the ratio of tantalum to niobium. The presence of more than one per cent. tungsten can lead to high results for niobium. Other elements that might be present in titanium alloys do not interfere with the method. The procedure is designed for titanium alloys containing 0.05 to 10 per cent. niobium. The method is reasonably rapid. Six determinations can be finished in two days. The method should be applicable to many other materials besides titanium alloys.     

Solvent extraction separation of tantalum from niobium on macro scale using di(2-ethylhexyl) phosphoric acid as extractant

A solvent extraction procedure for the separation of niobium and tantalum has been developed. The method consists of extracting tantalum from its aqueous mixture with niobium, with the help of di(2-ethylhexyl)phosphoric acid (HDEHP) in n-heptane. The aqueous feed consists of niobium and tantalum in an aqueous medium containing hydrochloric and oxalic acids. The concentrations of niobium and tantalum were raised to 1 mg/ml in the aqueous solution. The extraction efficiency of tantalum under these conditions was found to be 85%. Effects of chloride and oxalate ions as well as those of the concentration of HDEHP on the extraction efficiency were studied and discussed in detail.     

Spectrophotometric Determination of Simultaneously Present Niobium and Tantalum

The formation of niobium(V) and tantalum(V) complexes of 2,3,4-trioxyphenylazo-5-sulfonaphthalene in the presence of cetyltrimethylammonium bromide was studied by spectrophotometry. The effect of surfactants on the chemical and analytical properties of niobium(V) and tantalum(V) complexes of this reagent was studied. Procedures were developed for the spectrophotometric determination of niobium and tantalum present simultaneously as mixed-ligand complexes. The procedures were tested on model solutions.     

Determination of niobium and tantalum in binary alloys and zirconium alloys

Recent developments in the metallurgy of niobium, tantalum and zirconium have necessitated provision of analytical procedures for determining niobium and tantalum in the presence of each other and in the presence of zirconium. For this purpose, absorptioinetric procedures based on the formation of yellow coloured complexes, between pyrogallol and niobium or tantalum, have been critically examined. Direct absorptiometric procedures are described, which are suitable for determining niobium or tantalum in the range 2 to 7%; when either of these metals exceeds 7%, differential absorptiometric procedures are recommended. Corrections must lie made for absorption due to the presence of other metals which form complexes with pyrogallol. In tlie determination of niobium or tantalum up to 5%, the precision of the method is about ±0.05%. About 12 determinations can be made in a day, by one analyst.     

Extraction Recovery of Tantalum(V) and Niobium(V) from Hydrofluoric and Hydrofluoric-Sulfuric Acid Aqueous Solutions with Octanol

Comparative study of extraction of tantalum(V) and niobium(V) with octanol and tributyl phosphate was made. The data on distribution of tantalum(V) and niobium(V) between octanol and hydrofluoric and hydrofluoric-sulfuric acid aqueous solutions were obtained. The flowsheet for preparation of pure tantalum and niobium oxides was developed.     

Substoichiometric extraction of tantalum with diantipyrylmethane

Diantipyrylmethane is used for substoichiometric extraction of tantalum from 1—4M hydrofluoric acid into 1,2-dichlorethane. The selectivity of the method is good, niobium and antimony(V) being the main inteferences. The stoichiometric composition of the tantalum/diantipyrylmethane complex is 1:1. The method was usef for the determination of trace amounts of tantalum (0.52 ± 0.05 μ g^?1) in a lake sediment (Bodensee/Lake Constance) by neutron activation/μ-spectrometry. Tantalum was determined in niobium samples by an isotope dilution procedure after separation of the matrix on a polyurethane foam column loaded with diantipyrylmethane.     

Extractive Recovery of Tantalum(V) and Niobium(V) with Octanol from Hydrofluoric Acid Solutions Containing Large Amounts of Titanium(IV)

Extractive recovery with n-octanol of tantalum(V) and niobium(V) from hydrofluoric acid solutions containing large amounts of titanium (up to 2-3 M) was studied. The conditions were found for separation of tantalum(V) and niobium(V) from titanium(IV), allowing recovery of 95.7 and 84.1% of tantalum and niobium fluoride complexes, respectively, in one extraction cycle, with 2.6% recovery of titanium.     

电感耦合等离子体原子发射光谱法测定钛合金中钨、铌、钽

采用电感耦合等离子体原子发射光谱法（ICP-AES）法测定钛合金中W,Nb,Ta元素的含量。样品采用盐酸、氢氟酸和硝酸溶解,并对仪器工作参数和试验条件进行了优化试验,确定了仪器最佳工作条件,考察了钛合金基体和共存元素对待测元素的影响,确定了各待测元素谱线为W207．911nm,Nb309．418nm,Ta240．063nm。选定的待测元素分析线不受合金基体和共存元素的干扰,通过基体匹配消除基体的影响。加标回收率在98％104％之间,测定结果的相对标准偏差为0．3％～2．4％（n=8）,方法的检出限为0．003-0．013μg／mL。进行了标准物质对照试验,试验结果与标准值相符。