Using x-ray analogs of elements to be determined in the x-ray fluorescence analysis of liquid samples

To construct calibration characteristics in x-ray fluorescence analysis, it is proposed to use calibration samples that contain compounds of chemical elements whose bright characteristic lines are close in wavelength to the analytical lines of the analytes. This approach is efficient in determining rare and expensive elements. The proposed approach is checked experimentally in the determination of W, Re, Er, and Yb in solutions.