指甲电子顺磁共振谱图基线修正方法与精度分析

目的 在指甲电子顺磁共振剂量重建实验测量中风速、温度及湿度发生大范围变化时波谱则会出现较大程度的基线漂移,进而使得读出的数值不能反映真实的自由基浓度,最终会降低实验结果的可信度.本研究将提出一种基线修正的方法以解决这个问题.方法 找寻发生漂移后的基线,然后选定波谱修正范围和相应的修正函数或将原始波谱还原成能量吸收谱,选择点修正的方法对波谱进行修正.结果 在同一样品测量中,对发生基线漂移的波谱未加以修正得到的数值与未发生基线漂移时得到的数值在误差允许范围内相等的概率仅为31％;而利用此方法修正后概率则达到91％,提高了近3倍.结论 在对波谱进行读数之前,应使用此种修正方法对波谱进行基线修正,以此来提高剂量估算的准确度.

Reference line correcting method and accuracy analysis of fingernail electron paramagnetic resonance

Objective The spectrum has a greater baseline drift when wind speed,temperature and humidity change in the experiment of fingernail electron paramagnetic resonance dose reconstruction,and thus the read-out value does not reflect the true radical concentration,which ultimately reduces the credibility of the test results.This study aims to propose a reference line correcting method to solve the problem.Methods The drifted baseline was found out first,and then spectral correction range and the corresponding correction function were selected or the original spectrum was reduced to energy absorption spectrum.Finally,the point correction method was applied to modify the spectrum.Results The probability of the value obtained without reference line correcting for the spectrum of baseline drift equal to the value of spectrum without baseline drift was only 31％,while the probability was increased to 91％,improving nearly 3 times after using the reference line correcting method in the range of acceptable error.Conclusions This reference line correcting method for spectrum should be applied before reading the spectrum in order to increase the accuracy of dose estimation.