LIBS quantitative analysis method based on algebraic reconstruction incident vector solution

Abstract

The invention discloses an LIBS quantitative analysis method based on algebraic reconstruction incident vector solution. The method includes the steps of: employing a high precision optical tomographyreconstruction model for modeling of a multielement LIBS quantitative solving problem, and establishing a relationship among a standard sample normalized spectrum intensity matrix W, an incidence matrix F, and a standard sample atom fraction matrix P; performing column-by-column iteration solution to the column vectors of the incidence matrix F by means of high-precision ART iterative algorithm in optical tomography with combination of matrix column vector decomposition, thereby obtaining an incidence matrix F which reflects the correlation between the W and the P; and then according to the computing of an actual measurement normalized spectrum intensity vector and the incidence matrix of an unknown sample, achieving high-precision solution and analysis to every element in the unknown sample. By means of the method, influence of competitive emitting of different elements in a chemical matrix effect is solved. Through the ART tomography iterative algorithm for solution, the incidence matrix columns with minimum absolute error are obtained, thus increasing quantitative analysis precision of the LIBS.

Description

technical field [0001] The invention relates to a laser spectrum detection method, in particular to a quantitative laser-induced breakdown spectrum analysis method, which is suitable for simultaneous quantitative analysis and analysis of multiple elements in a detection target, and belongs to the field of photoelectric detection. Background technique [0002] Laser-induced breakdown spectroscopy (LIBS for short) uses short-pulse laser to focus on the target surface, and its instantaneous high temperature causes the target to be denuded to generate plasma. The spectral lines of information can be used to detect the constituent elements of matter. LIBS technology can achieve qualitative analysis of target elements well, but there are many difficulties in quantitative analysis, including: ablation hole effect, chemical matrix effect, etc. [0003] LIBS quantitative analysis is divided into unit analysis and multivariate analysis methods. The unit analysis method calibrates a ...

AI Technical Summary

Problems solved by technology

The advantage of this method is that it is relatively simple and practical, but the disadvantage is that it will be affected by the chemical matrix effect, and the accuracy of quantitative analysis is limited; the multivariate analysis method can simultaneously calibrate multiple calibration samples for multiple spectral lines of various elements of the target to be measured , by solving the multivariable mathematical matrix equation, the content of various elements of the target to be measured can be obtained

The advantage of this method is that it can eliminate the influence of chemical matrix effects on the accuracy of quantitative analysis to a certain extent. The disadvantage is that the accuracy of the solution algorithm depends on the previous multi-element calibration mathematical model and the design of the solution algorithm.

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