Multivariate correction in laser-enhanced ionization with laser samplingстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
Аннотация:The opportunity of normalizing laser-enhanced ionization (LEI) signals by several reference signals (RS) measured simultaneously has been examined in view of correcting variations of laser parameters and matrix interferences. Opto-acoustic, atomic emission and non-selective ionization signals and their paired combination were used as RS for Li determination in aluminum alloys (0-6% Mg, 0-5% Cu, 0-1 % Sc, 0-1% Ag). The specific normalization procedure in case of RS essential multicollinearity has been proposed. LEI and RS for each definite ablation pulse energy were plotted in Cartesian co-ordinates (x and y axes - the RS values, z axis - LEI signal). It was found that in the three-dimensional space the slope of the correlation line to the plane of RS depends on the analyte content in the solid sample. The use of this slope has therefore been proposed as a multivariate corrected analytical signal. Multivariate correlative normalization provides analytical signal free of matrix interferences for Al-Mg-Cu-Li alloys. The application of this novel approach to the determination of Li allows plotting unified calibration curves for M-alloys of different matrix composition.