Matrix Effect on Laser Induced Breakdown Spectroscopy of Fine Coal

The feasibility of laser—induced breakdown spectroscopy as a diagnostic tool for elementary analysis was documented widely,as well as the matrix effect of target material was proved to be remarkable impact on the spectral analysis． The influence of physical characteristics of fine coal，including particle size and area density，on the emission spectrum was surveyed，such as spectral intensity,standard deviation of characteristic spectrum and the detection threshold．An intense laser radiation with a wavelength of 1064 nm was used to ablate fine coal to form plasma plume，and the
emission spectrum emitted as the plasma cooling of was analyzed by high—resolution echelle grating spectrometer coupled to intensified CCD camera．The results suggest that moderate particle size and material density are more advantageous to quantitative analysis of coal by laser—induced breakdown spectroscopy than the smallest or biggest size，which can be interpretable by heat—transfer mechanism
in target after a shot of laser pulse．