In this study,an online detector system based on plastic scintillators is designed to monitor the activity of tritiated water in the liquid effluents of nuclear power plants.The feasibility of the detector is verified...In this study,an online detector system based on plastic scintillators is designed to monitor the activity of tritiated water in the liquid effluents of nuclear power plants.The feasibility of the detector is verified via simulation on Geant4,and the optimal detector structure size is determined.A back-end electronics system is designed and an experimental measurement platform forβ-rays based on a ^(40)KCl solution is constructed.Thirteen ^(40)KC solutions with different activities ranging from 10 to4500 Bq/L are measured,and 1300 V is determined as the optimal operating high voltage of the photomultiplier tubes.A linear fit is performed in 10-min counts,and the maximum linear goodness of fit(R^(2))achieved is 0.9992.Long-term stability measurements are performed for two detectors,one filled with air and the other with a ^(40)KCl solution exhibiting an activity of 2000 Bq/L.The relative deviation of the counts of the detector system every 10 min is 0.998%when the ^(40)KCl solution is used,and the maximum Gaussian R^(2) of the counts is 0.9849.展开更多
Currently,the liquid scintillation method is widely used to measure the activity of tritiated water in the primary circuit of nuclear power plants,which leads to the continuous production of radioactive waste during m...Currently,the liquid scintillation method is widely used to measure the activity of tritiated water in the primary circuit of nuclear power plants,which leads to the continuous production of radioactive waste during measurement.In addition,the real-time activity information of tritiated water cannot be obtained.To solve this problem,herein we present an online tritiated water measurement method based on plastic scintillators that used the optical transport process in the Geant 4 software toolkit to build a model of plastic scintillation detection for tritiated water.Through simulation,the basic geometric dimensions of the detector were determined.In this dimension,using one detector to measure for 3 h,when the tritiated water activity was 100 Bq/L,its resolution was 16%(16 Bq/L).In addition,calculations were performed for the presence of other background signals to obtain the minimum detectable concentration.展开更多
本文介绍用不同浓度的氚水(HTO)一次腹腔注入怀孕12和15 d 的 C57 BL/6J 雌鼠,观察出生后3.5 d 第一代(F_1)仔鼠背部皮肤毛囊黑色素细胞异常率。结果表明,当15 d 龄胎鼠接受氚累积吸收剂量为0.11—0.67 Gy 时,毛囊异常率为1.0%—5.1%;12...本文介绍用不同浓度的氚水(HTO)一次腹腔注入怀孕12和15 d 的 C57 BL/6J 雌鼠,观察出生后3.5 d 第一代(F_1)仔鼠背部皮肤毛囊黑色素细胞异常率。结果表明,当15 d 龄胎鼠接受氚累积吸收剂量为0.11—0.67 Gy 时,毛囊异常率为1.0%—5.1%;12 d 龄胎鼠接受氚累积吸收剂量为0.12—0.46 Gy 时,毛囊异常率为3.4%—6.0%。说明随着氚累积吸收剂量的增加,毛囊异常率也增加;胚胎早期接受氚照射的 F_1代仔鼠皮肤毛囊异常率较高,12 d 龄胎鼠接受氚水照射引起的毛囊异常率比15 d 龄胎鼠的明显增高。展开更多
基金supported by the National Natural Science Foundation of China (No. 12105029)。
文摘In this study,an online detector system based on plastic scintillators is designed to monitor the activity of tritiated water in the liquid effluents of nuclear power plants.The feasibility of the detector is verified via simulation on Geant4,and the optimal detector structure size is determined.A back-end electronics system is designed and an experimental measurement platform forβ-rays based on a ^(40)KCl solution is constructed.Thirteen ^(40)KC solutions with different activities ranging from 10 to4500 Bq/L are measured,and 1300 V is determined as the optimal operating high voltage of the photomultiplier tubes.A linear fit is performed in 10-min counts,and the maximum linear goodness of fit(R^(2))achieved is 0.9992.Long-term stability measurements are performed for two detectors,one filled with air and the other with a ^(40)KCl solution exhibiting an activity of 2000 Bq/L.The relative deviation of the counts of the detector system every 10 min is 0.998%when the ^(40)KCl solution is used,and the maximum Gaussian R^(2) of the counts is 0.9849.
基金supported by the National Natural Science Foundation of China(No.12105029)。
文摘Currently,the liquid scintillation method is widely used to measure the activity of tritiated water in the primary circuit of nuclear power plants,which leads to the continuous production of radioactive waste during measurement.In addition,the real-time activity information of tritiated water cannot be obtained.To solve this problem,herein we present an online tritiated water measurement method based on plastic scintillators that used the optical transport process in the Geant 4 software toolkit to build a model of plastic scintillation detection for tritiated water.Through simulation,the basic geometric dimensions of the detector were determined.In this dimension,using one detector to measure for 3 h,when the tritiated water activity was 100 Bq/L,its resolution was 16%(16 Bq/L).In addition,calculations were performed for the presence of other background signals to obtain the minimum detectable concentration.
文摘本文介绍用不同浓度的氚水(HTO)一次腹腔注入怀孕12和15 d 的 C57 BL/6J 雌鼠,观察出生后3.5 d 第一代(F_1)仔鼠背部皮肤毛囊黑色素细胞异常率。结果表明,当15 d 龄胎鼠接受氚累积吸收剂量为0.11—0.67 Gy 时,毛囊异常率为1.0%—5.1%;12 d 龄胎鼠接受氚累积吸收剂量为0.12—0.46 Gy 时,毛囊异常率为3.4%—6.0%。说明随着氚累积吸收剂量的增加,毛囊异常率也增加;胚胎早期接受氚照射的 F_1代仔鼠皮肤毛囊异常率较高,12 d 龄胎鼠接受氚水照射引起的毛囊异常率比15 d 龄胎鼠的明显增高。
