一、引言 近年来,LiF,CaF_2,Mg_2SiO_4:Tb和CaSO_4:Dy/Tm等热释光元件已广泛地用于环境γ辐射测量。由于环境中天然γ辐射的照射量低,使监测工作的周期长且受环境因素影响多。 LiF:Mg,Ti 是一种组织等效材料,但相对灵敏度低,对于低照射量的测量是不理想的。天然CaF_2和Mg_2SiO_4:Tb的灵敏度高,但光敏和假荧光严重,用于小剂量测量时受 I. INTRODUCTION In recent years, the thermoluminescent elements such as LiF, CaF_2, Mg_2SiO_4: Tb and CaSO_4: Dy / Tm have been widely used in environmental gamma radiation measurement. Due to the low exposure to natural gamma radiation in the environment, monitoring work is long and subject to environmental factors. LiF: Mg, Ti is a tissue-equivalent material, but its relative sensitivity is low, which is not ideal for low exposure measurements. Natural CaF_2 and Mg_2SiO_4: Tb have high sensitivity, but are sensitive to light and false fluorescence. They are used in low dose measurement