Effect of the conditions of sample preparation for x-ray fluorescence analysis on the effect of microabsorption heterogeneity

摘要

The dual effect of the microabsorption heterogeneity (MAH) of emitters on the fluorescence intensity (I-fl) is shown on the basis of the literature data. The duality is due to the covering of large fluorescent grains by small filler particles (II type effect) and its absence (I type effect). For some materials, the effect of MAH can change not only in magnitude but also in sign. It is shown experimentally that the prediction of the covering effect is difficult. It was found that, upon crushing multicomponent materials, different granulometric fractions differ in their chemical composition. This makes the theoretical account of the effect of the MAH of the emitter on the results x-ray fluorescence analysis hardly probable. It is shown that the experimental account by means of radiation scattered (I-sigma) or absorbed (I-ab) by the sample possible only in a particular case, because the dependences I-fl,I-sigma, and I-ab on the particle size differ in nature.