Desrosiers Marc F, Lin Min, Cooper Sarenée L, Cui Ying, Chen Kesheng
Ionizing Radiation Division, Physics Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
Radiat Prot Dosimetry. 2006;120(1-4):235-7. doi: 10.1093/rpd/nci543. Epub 2006 Apr 27.
Alanine dosimetry is now well established both as a reference and routine dosemeter for industrial irradiation processing. Accurate dosimetry under the relatively harsh conditions of industrial processing requires a characterisation of the parameters that influence the dosemeter response. The temperature of the dosemeter during irradiation is a difficult quantity to measure so that the accuracy of the temperature coefficient that governs the dosemeter response becomes a critical factor. Numerous publications have reported temperature coefficients for several types of alanine dosemeters. The observed differences in the measured values were commonly attributed to the differences in the polymer binder or the experimental design of the measurement. However, the data demonstrated a consistent difference in the temperature coefficients between l-alanine and dl-alanine. Since there were no commonalities in the dosemeter composition or the measurement methods applied, a clear conclusion is not possible. To resolve this issue, the two isomeric forms of alanine dosemeters were prepared and irradiated in an identical manner. The results indicated that the dl-alanine temperature coefficient is more than 50% higher than the l-alanine temperature coefficient.
丙氨酸剂量计现已成为工业辐照加工的一种成熟的参考和常规剂量计。在工业加工相对苛刻的条件下进行精确剂量测定，需要对影响剂量计响应的参数进行表征。辐照期间剂量计的温度是一个难以测量的量，因此控制剂量计响应的温度系数的准确性成为一个关键因素。许多出版物报道了几种类型丙氨酸剂量计的温度系数。测量值中观察到的差异通常归因于聚合物粘合剂的差异或测量的实验设计。然而，数据表明L-丙氨酸和DL-丙氨酸的温度系数存在一致的差异。由于剂量计组成或所应用的测量方法没有共性，因此无法得出明确的结论。为了解决这个问题，制备了两种异构体形式的丙氨酸剂量计，并以相同的方式进行辐照。结果表明，DL-丙氨酸温度系数比L-丙氨酸温度系数高50%以上。
