| 摘要 |
FIELD: environmental protection. ^ SUBSTANCE: invention relates to radio-ecological monitoring that can be used to determine alpha-emitting radionuclides in environmental samples, in particular for alpha-spectrometric determination of isotope proportions of 240Pu and 239Pu, 238Pu and 241Am, 235U and 236U. Technical result of invention resides in possibility of simultaneously determining activities of all alpha-emitting radionuclides, increased accuracy of simultaneous determination of isotope proportions of energetically close isotopes, and separating above-indicated duplets. Identification of alpha-emitting radionuclides involves environmental and technological sampling, treating samples, preparing samples for measurements, measuring and recording spectrum of sample, minimizing deviations of model spectrum from sample spectrum, and determining content of alpha-emitting radionuclides in the sample. When sample is being prepared, summary activity of sample is preliminarily determined, after which isotope solution is introduced into sample as internal standard with known energy and specified activity of alpha-emission of the sample. Based on sample spectrum measurement results and minimizing deviations of model spectrum from sample spectrum in internal standard region, parameters of asymmetric Gauss distribution describing internal standard peak are determined. Identification of alpha-emitting radionuclides is accomplished using semiconductor spectrometer and total energy scale of spectrometer is utilized, whereas spectrum of individual radionuclide is described according to proposed proportion. Minimization of deviations of model spectrum from sample spectrum is effected in three steps. ^ EFFECT: enabled simultaneous accurate determination of activities of energetically close isotopes. ^ 9 dwg, 3 tbl, 4 ex |
