CHEMICAL MODIFICATION BY ASCORBIC-ACID AND OXALIC-ACID IN GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY

被引：27

作者：

BYRNE, JP

CHAKRABARTI, CL

GILCHRIST, GFR

LAMOUREUX, MM

BERTELS, P

机构：

[1] UNIV TECHNOL SYDNEY,DEPT CHEM,POB 123,BROADWAY,NSW 2007,AUSTRALIA

[2] CARLETON UNIV,DEPT CHEM,CTR ANALYT & ENVIRONM CHEM,OTTAWA K1S 5B6,ONTARIO,CANADA

来源：

ANALYTICAL CHEMISTRY | 1993年 / 65卷 / 09期

关键词：

D O I：

10.1021/ac00057a025

中图分类号：

O65 [分析化学];

学科分类号：

070302 ; 081704 ;

摘要：

The effects of addition of ascorbic and oxalic acids on the atomic absorption signal for lead are explained by a gas-phase thermodynamic equilibrium model. The gas-phase composition of the graphite furnace was determined as samples containing ascorbic or oxalic acid were pyrolyzed. Hydrogen and carbon monoxide were identified as two of the major pyrolysis products. The amounts of these reducing gases, formed in the atomization cycle, varied with the modifier used, the charring temperature employed, and the condition of the surface of the pyrolytically coated graphite tube. The extent of the shift in the appearance temperature showed correlation with variations in concentrations of hydrogen and carbon monoxide produced by pyrolysis. Results for oxalic acid clearly showed that the appearance temperature shifts for lead in pyrolytically coated tubes cannot be explained by a surface reaction mechanism.

引用

页码：1267 / 1272

页数：6

共 17 条

[1] MECHANISMS OF LEAD VAPORIZATION FROM AN OXYGENATED GRAPHITE SURFACE USING MASS-SPECTROMETRY AND ATOMIC-ABSORPTION [J].