L-Glutamic acid (L-GA) pellets (3.8 mm × 4 mm) and powder dosimeters were studied in the dose range of 0.1-150 kGy using the electron paramagnetic resonance (EPR) technique. The EPR spectra of irradiated L-GA pellets showed an EPR signal with eight lines, and the intensity of the signal increased with an increase of absorbed dose. The results obtained in terms of the energy-absorption coefficients suggest a similar performance of the L-GA pellets as compared to alanine pellets. The value of the temperature coefficient for the L-GA pellets during irradiation was around - 0.08%/°C which is lower than that reported for alanine dosimeter, 0.14%/°C. The influence of humidity on the pellet response was found to be negligible; i.e., the increase in response was only about 2% for a relative humidity of up to 94%. The response of L-GA powder reached stability 4 h after irradiation and continued to be stable until 47 days after irradiation. In contrast, the response of the L-GA pellet dosimeter reached stability 22 h after irradiation and continued to be stable until 8 days after irradiation. For routine applications, the L-GA pellet dosimeter should be analyzed during the stable period after irradiation, to minimize the uncertainties in dose assessment. The overall two-sigma uncertainties in absorbed dose estimation were 5.1% and 3.9% for the dose ranges of 0.1-15 kGy and 15-150 kGy, respectively. It is concluded that L-GA pellets represent a promising dosimeter material for quantification of radiation doses in food irradiation, medical sterilization and polymer modification.

中文翻译：

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一种新的基于谷氨酸的EPR剂量计，用于辐射处理应用。

使用电子顺磁共振（EPR）技术研究了0.1-150 kGy剂量范围内的L-谷氨酸（L-GA）颗粒（3.8 mm×4 mm）和粉末剂量计。辐照的L-GA药丸的EPR谱显示8条线的EPR信号，并且信号强度随吸收剂量的增加而增加。根据能量吸收系数获得的结果表明，与丙氨酸颗粒相比，L-GA颗粒的性能相似。辐照期间L-GA颗粒的温度系数值约为-0.08％/°C，低于报道的丙氨酸剂量计的0.14％/°C。发现湿度对沉淀反应的影响可以忽略不计；也就是说，相对湿度高达94％时，响应的增加仅约2％。L-GA粉末的响应在照射后4小时达到稳定，并持续稳定直到照射后47天。相反，L-GA沉淀物剂量计的响应在照射后22 h达到稳定，并持续稳定直到照射后8天。对于常规应用，应在辐照后的稳定期内对L-GA颗粒剂量计进行分析，以最大程度地减少剂量评估中的不确定性。在0.1-15 kGy和15-150 kGy的剂量范围内，吸收剂量估算中的总体两个西格玛不确定性分别为5.1％和3.9％。结论是，L-GA颗粒代表了一种有前途的剂量计材料，可用于量化食品辐照，医疗灭菌和聚合物改性中的辐射剂量。