Aşlar Engin, Şahiner Eren, Polymeris George S, Meriç Niyazi
Institute of Nuclear Sciences, Ankara University, 06100 Beşevler, Ankara, Turkey.
Institute of Nuclear Sciences, Ankara University, 06100 Beşevler, Ankara, Turkey.
Appl Radiat Isot. 2017 Nov;129:142-151. doi: 10.1016/j.apradiso.2017.08.026. Epub 2017 Aug 24.
The trapping parameters of BeO thermoluminescence peaks 2 and 3 (with delocalization temperatures of 192 and 308°C respectively, obtained with heating rate of 1K/s) have been calculated using various analysis techniques, including the peak shape methods, isothermal decay, variable heating rates, the fractional glow technique and de-convolution. However, as BeO has been reported to undergo thermal quenching, both intensity as well as trapping parameters are affected, because the glow curve is distorted. Therefore, trapping parameters were calculated for both quenched and unquenched data of the aforementioned thermoluminescence peaks. The unquenched glow curves were determined by reconstructing the corresponding quenched; the following thermal quenching parameters were adopted: W = 0.60eV and C = 1.3 × 10 for peak 2 and W = 0.80eV and C = 1.2 × 10 for peak 3. The obtained activation energies and frequency factors before and after reconstruction were compared both for every method and also to previous studies. This study emphasizes the importance of reconstruction process on trapping parameters for peak 3, as this peak lies within a special temperature range where the efficiency gets values < 0.54. The main dosimetric peak is mildly affected by thermal quenching; thus before and after reconstruction the corresponding values do not yield significant variations. The average values for the activation energy and frequency factor after reconstruction were calculated as 1.14 ± 0.07eV and 9.9 × 10 ± 0.4 × 10 s for peak 2; the corresponding values for peak 3 are 1.34 ± 0.08eV, 6.9 × 10 ± 0.6 × 10 s respectively. Both peaks are described by first order of kinetics even after reconstruction has occurred. Individual peculiarities of each analysis technique has been both presented and discussed.
已使用多种分析技术计算了BeO热释光峰2和峰3的俘获参数(分别在1K/s加热速率下获得的离域温度为192和308°C),这些技术包括峰形法、等温衰减、可变加热速率、分数发光技术和解卷积。然而,由于据报道BeO会发生热猝灭,强度和俘获参数都会受到影响,因为发光曲线会失真。因此,针对上述热释光峰的猝灭和未猝灭数据都计算了俘获参数。未猝灭的发光曲线通过重建相应的猝灭曲线来确定;采用了以下热猝灭参数:峰2的W = 0.60eV和C = 1.3×10,峰3的W = 0.80eV和C = 1.2×10。对于每种方法以及与先前的研究,都比较了重建前后获得的活化能和频率因子。本研究强调了重建过程对峰3俘获参数的重要性,因为该峰位于一个特殊温度范围内,在此温度范围内效率值<0.54。主要剂量峰受热猝灭的影响较小;因此,重建前后相应的值没有显著变化。重建后峰2的活化能和频率因子的平均值计算为1.14±0.07eV和9.9×10±0.4×10 s;峰3的相应值分别为1.34±0.08eV、6.9×10±0.6×10 s。即使在重建之后,两个峰均由一级动力学描述。已介绍并讨论了每种分析技术的个别特点。