METHOD FOR IDENTIFYING RADIONUCLIDES IN SAMPLES USING LIQUID SCINTILLATION COUNTER Russian patent published in 1999 - IPC

FIELD: radiation monitoring of environment including monitoring of activity of alpha radiating nuclides. SUBSTANCE: method involves taking samples and preparing them for measurement using liquid scintillation counter, measuring and recording sample spectrum and measurement parameters, convoluting hardware spectrum of sample into group, producing model spectrum of sample on the basis of library base spectrums, minimizing model spectrum deviation from sample spectrum, and determining content of radionuclides in sample. Alpha radiating nuclides are identified in samples when interference radionuclides are present in taken samples. To this end, in preparing solid sample, it is annealed before opening, then opened by means of concentrated nitrous acid and hydrogen peroxide, concentrated by evaporation to wet salt state, wet residue it transformed to hydrochloric acid solution and concentrated by evaporation. Concentrated orthophosphoric acid is added to solution obtained and concentrated by evaporation. Solution is cooled down and transferred to scintillation mixture. Sample is measured by means of liquid scintillation counter, specimen spectrum obtained is recorded and grouped. Deviation of model spectrum from sample one is minimized. Specimen obtained has adequate degree of quenching which makes it possible to discriminate and identify alpha active nuclides in the background of accompanying radionuclides with high degree of accuracy. EFFECT: improved sensitivity of spectrometric analysis which improves validity of identification of radionuclides in solid samples. 5 dwg, 4 tbl