开叉毛细管HG-FAAS测定地质样品中的锑、铋

氢化物发生原子吸收法(HG-FAAS)广泛应用于冶金、地质、环境、医药和食品分析等领域中。研究表明,氢化物发生法的检出限、测定精度以及干扰等情况与原子化器和氢化物发生器的结构以及传输过程有关[1]。郭小伟等[2-4]研制了用于火焰原子吸收光谱分析的双毛细管喷雾器,并利用其测     

Hydride generation – in-atomizer collection of Pb in a quartz trap-and-atomizer device for atomic absorption spectrometry – an interference study

Interferences of selected hydride forming elements (As, Sb, Bi, Se and Sn) on lead determination by hydride generation atomic absorption spectrometry were extensively studied in both on-line atomization and preconcentration (collection) modes. The commonly used on-line atomization mode was found free of significant interferences, whereas strong interference from Bi was observed when employing the preconcentration mode with plumbane collection in a quartz trap-and-atomizer device. Interference of Bi seems to take place in the preconcentration step. Interference of Bi in the collection mode cannot be reduced by increased hydrogen radical amount in the trap and/or the atomizer.     

Determination of As,Sb and Bi in high-purity copper by electrothermal atomic absorption spectrometry

As, Sb and Bi were determined in copper electric cables by atomic absorption spectrometry with electrothermal atomization in a graphite furnace. The interferences in the determination of As, Sb and Bi caused by eleven cationic species and six types of acid were studied. The different volatilization of the copper matrix in comparison to the analyte was studied, as a means of increasing the analyte signal/non-specific absorption signal ratio.     

Multiple microflame quartz tube atomizer: Study and minimization of interferences in quartz tube atomizers in hydride generation atomic absorption spectrometry

A systematic study was performed to evaluate the performance of a multiple microflame (MM) quartz tube atomizer (QTA) for minimizing interferences and to improve the extent of the calibration range using a batch system for hydride generation atomic absorption spectrometry (HG AAS). A comparison of the results with conventional QTA on the determination of antimony, arsenic, bismuth and selenium was performed. The interference of As, Bi, Se, Pb, Sn and Sb was investigated using QTA and MMQTA atomizers. Better performance was found for MMQTA, and no loss of linearity was observed up to 160 ng for Se and Sb and 80 ng for As, corresponding to an enhancement of two times for both analytes when compared to QTA (analyte mass refers to a volume of 200 μl). For Bi, the linear range was the same for QTA and MMQTA (140 ng). With the exception of Bi, the tolerance limits for hydride-forming elements were improved more than 50% in comparison to the conventional QTA system, especially for the interferences of As, Sb and Se. However, for Sn as an interferent, no difference was observed in the determination of Se and Sb using the MMQTA system. The use of MMQTA-HG AAS complied with the relatively high sensitivity of conventional QTA and also provided better performance for interferences and the linear range of calibration.     

Polagraphic determination of some metal diethyldithiocarbamates

The polarographic behaviour of Cu, Pb, Zn, Mn, Cd, Ni and Bi diethyldithiocarbamates in benzene-methanol media was examined. A separation method was developed which allowed polarographic determination of all of these complexes without mutual interferences. Good precision and accuracy were obtained in the analysis of artificial mixtures and standard samples.     

Determination of Bismuth in Geological Materials by Flow Injection Hydride Generation Atomic Absorption Spectrometry

Abstract

Flow injection analysis (FIA) has been applied to sample introduction in conjunction with automated hydride generation and AAS techniques for the determination of Bi in rock samples. The powdered rock sample is digested with a mixture of hydrofluoric, perchloric, and nitric acids. The evolved hydride is carried through to a heated quartz tube by a stream of argon, and the atomic absorption of Bi is measured at 223.2 nm.

Thiosemicarbazide and 1,10 - phenanthroline are used as masking agents to control interferences from Cu and Ni. The method permits the accurate determination of Bi in geological materials at levels as low as 10 ppb with an analysis rate of more than 50 digested samples per hour. Bi values on 13 international geological reference samples are reported.     

Study of the effects of elements that form volatile hydrides on the determination of selenium by hydride generation atomic absorption spectrometry

Summary A study has been made of possible interferences upon the determination of selenium by hydride generation atomic absorption spectrometry (HGAAS), due to the presence of other hydride forming elements such as As, Ge, Bi, Te, Sn and Sb, and to a volatile element such as Hg. The interfering effects of these cations were determined at several concentration levels using sodium borohydride as the reductant and a commercially available semi-automatic system for the generation and the flameless combustion of the hydrides. It has been demonstrated that the determination of selenium by HGAAS is relatively free from interferences with regard to other elements that form volatile hydrides, except for tin and bismuth that strongly interfere.

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Einfluß von flüchtige Hydride bildenden Elementen auf die Selenbestimmung als Hydrid durch AAS

Zusammenfassung Bei der AAS-Bestimmung von Selen als Hydrid wurde der Einfluß der hydridbildenden Elemente As, Ge, Bi, Te, Sn, Sb sowie auch des flüchtigen Elements Hg untersucht. Die Untersuchungen wurden bei verschiedenen Konzentrationen mit Natriumborhydrid als Reduktionsmittel durchgeführt. Dabei wurde ein handelsübliches halbautomatisches System zur Erzeugung und flammenlosen Verbrennung der Hydride benutzt. Es zeigte sich, daß die Selenbestimmung bis auf die stark störenden Elemente Sn und Bi relativ frei von Beeinflussungen ist.

     

Investigations of trace analysis of A(III)B(V) semiconductor microsamples by atomic spectroscopy-VII Investigation of trace and thin-layer analysis of doping elements (Ag, Au, Bi, Cd, Sn, Tl) in InAs by atomic-absorption with electrothermal evaporation

Etching procedures for separation of thin layers of InAs (up to 1.4 mum thick) have been developed and optimized. A solid-state microtome has been used for cutting layers thicker than 1mum. AAS/ETA methods for determination of traces of Ag, Au, Bi, Cd, Sn, and Tl have been developed. The matrix interferences of nitric add, hydrobromic acid, and As(3+) or In(3+) in nitric or hydrobromic acid have been studied. The main causes of the matrix interference are the formation of diatomic molecules between the trace and matrix components, and the effect of the evaporation processes. By use of the platform technique with special platforms some matrix interferences could be minimized. For the determination of traces of Sn, matrix modification with Ni(NO(3))(2) as additive gave the best analytical values. For the trace determination of Au, separation of In from Au by evaporation of InBr(3) from 0.6M HBR medium in the AAS ashing phase was developed. The detection limits are in the 10(16) atoms/cm(3) region for layers of 1 mum thickness and surface area 1 cm(2).     

Optimization of the simultaneous batch determinations of Bi(III), Hg(II) and Cu(II) at an epoxy-graphite electrode bulk modified with 2-mercaptobenzothiazole

An epoxy-graphite tube composite electrode bulk modified with 2-mercaptobenzothiazole was investigated for the simultaneous, batch determinations of Bi(III), Hg(II) and Cu(II) by differential-pulse anodic stripping voltammetry after open circuit preconcentration of the three metal ions. Systematic optimization was studied with respect to resolution and sensitivities of the differential-pulse peaks. The resolution between peaks was quantified and employed in a window diagram approach to choose the best conditions. The developed method gave detection limits of 4.2 x 10(-9), 3.6 x 10(-9) and 9.5 x 10(-8) M for Hg(II), Bi(III) and Cu(II), respectively (S/N = 3; 3 min preconcentration). The conditions whereby simultaneous determinations could be performed in the absence of cross-interferences of the analytes were also examined. Additional selected substances in the sample background were also studied for possible interferences. The developed method was applied to the simultaneous, batch determinations of Bi(III), Hg(II) and Cu(II) in a standard sample and a human hair sample.     

Square-wave voltammetric determination of thallium using surface modified thick-film graphite electrode with Bi nanopowder

Trace analysis of thallium at surface modified thick-film graphite electrode with Bi nanopowder has been carried out using square-wave anodic stripping voltammetry (SWASV) technique. The Bi nanopowder electrode exhibited a well-defined response relating to the oxidation of Tl. From the linear relationship between Tl concentration and peak current, the sensitivity of the Bi nanopowder electrode was quantitatively estimated. The detection limit of Tl was determined to be 0.03 μg/L for 1.0 μg/L Tl solution under 10 min accumulation, which is lower than the reported values for a Bi film electrode. Furthermore, it is confirmed that EDTA addition effectively eliminates the Pb and Cd interferences in the course of Tl determination by forming complexes with Pb²⁺ and Cd²⁺.