Exploration of multichannel superposition testing technology based on atomic fluorescence spectrometer
When multi-channel atomic fluorescence spectrometer is used to measure a variety of elements,due to the differences in the required medium,the concentration of the medium and the working conditions for the generation of vapors of various elements,the working conditions that compromise with each other are often used,rather than the optimal conditions for each element,which limits the sensitivity and accuracy of the measurement results.In this study,a multi-channel superposition testing technology was proposed based on the multi-channel atomic fluorescence spectrometer.The atomic fluorescence signal intensity was enhanced without the introduction of noise,thus improving the overall technical performance of the instru-ment.On the basis of the two-channel atomic fluorescence spectrometer,the test results of As and Hg using multi-channel superposition testing technology were compared with those without multi-channel superposi-tion testing technology.The improvement effect of multi-channel superposition testing technology on the sensitivity,precision and trueness of the instrument was investigated.The results showed that the testing sensitivity of As and Hg increased by one-fold than that without this technology when two calibration curve solution series of As and Hg were determined separately.The blank solution of 5%(volume fraction)hydrochloric acid was determined in parallel for 11 times,and it was found that the detection limits of in-strument for As and Hg were reduced by half compared with those without this technology.The standard solutions of As(5.0 ng/mL)and Hg(0.50 ng/mL)were determined according to the experimental meth-od,and the relative standard deviations(RSD)of determination results were slightly lower compared with those without this technology.The contents of As and Hg in three certified reference materials of soil were deter-mined in parallel for 7 times,and the relative error(RE)of the determination results was reduced by about 1/3.