Kinetic analysis of MgB 4 O 7 :Dy,Na thermoluminescence under large heating-rate-dependent glow-peak shifts

Temperature lag between a thermoluminescent sample and the heating system can distort glow curves and the kinetic parameters derived from them. The main MgB 4 O 7 :Dy,Na glow peak was recorded at heating rates of 1–8 K s -1 and analyzed using the Chen, Hoogenstraaten, initial-rise, and computerized glow-curve deconvolution methods. An increase in peak temperature from 439.6 to 569.6 K was observed. Following a common model-based temperature transformation, effective activation-energy estimates of 0.762–0.966, 0.443, 0.555–0.820, and 0.691–0.878 eV were obtained using the four methods, respectively. The transformation increased the Hoogenstraaten estimate from 0.255 to 0.443 eV but did not eliminate the disagreement between methods. The results quantify the sensitivity of kinetic estimates to temperature treatment and data processing.