RESUMO
210Po and 210Pb exist widely in nature, and they have strong toxicity and strong ionization ability, which can cause continuous harm to human health. Therefore, it is of great significance to determine the activity concentrations of 210Po and 210Pb in environmental samples and to evaluate their harmful effects on human health. This article reviews the research progress in analytical methods and measurement techniques of 210Po and 210Pb in environmental samples.
RESUMO
Objective To investigate effect of high dose irradiation on the performances of thermolumines-cence detectors (LiF:Mg, Cu, P). Methods The high-dose irradiated thermoluminescence detector was annealed by a thermoluminescence annealing furnace until the annealing was completed, and then the annealed thermoluminescent detector was irradiated 0.5Gy by 137Cs irradiator to verify the accuracy of the thermoluminescentdetector. Results The thermoluminescence detector after high-dose irradiation could not be completely annealed under the temperature condition of 240 ℃, and it could be completely annealed at a high temperature as 400℃. After 0.5 Gy irradiation by 137Cs irradiator, the measurement results of the annealed thermoluminescence detector were significantly smaller, and the dose response and dispersion of the detector were also changed significantly. Conclusions After a more than 5 Gy irradiation, the crystal structure of the thermoluminescence detector has changed, and a high temperature peak above 240 ℃ has appeared, which leads to the failure to completely anneal at normal temperature. Therefore, the thermoluminescence detector can no longer be used for dosimetry after high-dose irradiation.