• Journal of Korean Ophthalmic Optics Society
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• v.4 no.2
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• pp.141-146
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• 1999

We measured and analyzed thermoluminescence spectra of $LaAlO_3$, single crystal by 3 dimensional data for temperature, wavelength and luminescence intensity. $LaAlO_3$, has used as the substrates of YBCO(superconductor) or semiconductors. We could determined the energy of recombination center, that is impossible through analysis of glow curve data. We could obtained the energy through analysis of the spectrum data at peak temperature by Franck-Condon model. The total glow curve was deconvoluted to three glow curves by curve fitting method. The activation energies were 0.54eV, 0.91eV and 1.02eV respectively. The energies of recombination centers were determined with 2.04eV and 2.75eV from the analysis of luminescence intensity data for wavelength.

• Progress in Medical Physics
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• v.4 no.2
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• pp.49-58
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• 1993

The complex glow curves were split into isolated glow curves to be calculated the values of kinetic order, activation energy, escape frequency and density of initial trap from the independent glow curves using the mathematical method of thermally stimulated processes. The minimization of the intensity difference between measured and theoretical glow curve was done by the nonlinear least-square program. The results of the fitted curves were almost equal to the actual values of the parameters. Thermoluminescence from gamma ray irradiated ${\alpha}$-Al$_2$ $O_3$ over the range of 300K to 600K was split into six glow curves. The kinetic order, activation energy and escape frequency of first glow curve were obtained as 1, 1.12eV and 6.79X10$\^$12/sec$\^$-1/, respectively, which were similar to the results of other method. Also the parameters of the second and the third glow curve and so forth were calculated.

• Journal of Sensor Science and Technology
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• v.8 no.5
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• pp.388-393
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• 1999

In this study, the $CaSO_4:Eu$ TLDs are fabricated and their trap parameters are determined. The optimum concentration of Eu for fabrication of the $CaSO_4:Eu$ TLD is 0.5 mol% and optimum temperature is $600^{\circ}C$ for 2 hours sintering in air. The glow curve of $CaSO_4:Eu$ consists of two glow peaks and these peaks are isolated by thermal bleaching method. Trap parameters of two glow peaks are measured using the initial rise, the peak shape, the heating rate and the least square curve fitting methods. The activation energies of the glow peak I and II are 1.00 eV and 1.09 eV, and the frequency factors are $7.04{\times}10^{11}\;s^{-1}$ and $5.12{\times}10^{11}\;s^{-1}$ and the kinetic orders are 1.11 and 1.33, respectively.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.4
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• pp.777-782
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• 2009

In this paper, the effect of the secondary electron emission coefficient of Xe ion on glow discharge was examined by ID numerical simulation. The simulation was performed for two distinct structures, short and long gaps. The features of the glow discharges in the both structures, firing and sustain voltages, luminance, and efficiency, were analyzed at various secondary electron emission coefficient of Xe ion.

• Nuclear Engineering and Technology
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• v.6 no.1
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• pp.3-8
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• 1974

The annealing of natural beryl powder used for the thermoluminescent dosimetry was investigated in order to eliminate effect of previous exposure. Through the glow curve analysis, the optimal annealing treatment was found to be one hour annealing at 145$0^{\circ}C$, but annealing for one hour at 55$0^{\circ}C$ was sufficient for reuse of natural beryl powder. There are two distinguished glow peaks at $65^{\circ}C$ and 20$0^{\circ}C$ of heating temperature during readout process. The $65^{\circ}C$ glow peak fades away rapidly, but the 20$0^{\circ}C$ glow peak remains very stable. It is, therefore, quite feasible to use the 20$0^{\circ}C$ glow peak for thermoluminescent dosimetry.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.206-211
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• 2008

Photostimulated luminescence(PSL)-Thermoluminescence(TL) combined analysis was applied to detect whether composite seasoning products and spices were irradiated or not. Samples were irradiated with $^{60}Co$ at $0{\sim}7$ kGy. A total of 12 different samples(6 of composite seasoning products and 6 of spices) was examined. Depending on the PSL results, TL analysis was performed. In case of both PSL positive(${\geq}5,000$ counts) and intermediate($700{\sim}5000$ counts), TL analysis had to be performed to confirm the result of PSL. Using TL, the shape of the glow curve(Glow 1) made it possible to identify the irradiated samples. In addition, The TL glow ratio(Glow 1/Glow 2) obtained by normalization was less than 0.1 for the non-irradiated samples and ${\geq}0.29$ for irradiated ones, respectively.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.1
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• pp.149-153
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• 2001

Three-dimensional thermoluminescence(TL) spectra of LiF: Mg, Cu, Na, Si TL material based on temperature, wavelength and intensity were measured and analyzed. The glow curves were obtained by integration of luminescence intensity for wavelength at each temperature, and various trapping parameters related to the trap formation were determined by analyzing these curves. Computerized glow curve deconvolution(CGCD) method which based on general order kinetics(GOK) model were used for the glow curve analysis. The glow curves of LiF:Mg, Cu, Na, Si TL material were deconvoluted to six isolated glow curves which have peak temperature at 333 K, 374 K, 426 K, 466 K, 483 K and 516 K, respectively. The 466 K main glow peak had an activation energy of 2.06 eV and a kinetic order of 1.05. This TL material was also found to have three recombination centers, 1.80 eV, 2.88 eV and 3.27 eV by TL spectra analysis based on Franck-Condon model. It showed that 2.88 eV is the dominant center, followed by 3.27 eV level, and 1.80 eV center is ascertained as emission center of this material even though its very weak emission intensity.

• Journal of radiological science and technology
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• v.21 no.2
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• pp.53-56
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• 1998

Highly sensitive $CaSO_4:Tm$ TLD is fabricated and their trap parameters are determined. The glow curve of $CaSO_4:Tm$ consists of three glow peaks and these peaks are isolated by the thermal bleaching method. The isolated glow peaks are fitted by a least squares method. The activation energies are 0.68, 0.82 and 1.03 eV. The frequency factors are $8.09{\times}10^8,\;9.14{\times}10^8$ and $1.03{\times}10^9/s$, and the kinetic orders are 1.37, 1.54 and 1.68, respectively. The optimum temperature range of the main peak for radiation dosimetry is between 220 and $290^{\circ}C$.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.372-375
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• 2009

We have studied on plasma diagnosis, characteristics of the glow discharge at the several different conditions of pressure, discharge current and such. The discharge onset voltage and onset current decreased as pressure increase, the general trend was nearly in agreement with the left regions of Paschen's curve. As normal glow discharge, discharge voltage was constant according to discharge current.

• Analytical Science and Technology
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• v.8 no.4
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• pp.443-448
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• 1995

Three anode configurations of six-jet, cone-jet and cylindrical-jet are tested for their analytical performance under power mode operation. The effect of pressure, power and gas flow rate on atomic absorption signals have been studied. The increase of atomic absorption signal of sample element is observed at a fixed pressure in all configurations as the gas flow rate increase up to 300-600 seem, and as the power dissipated in the glow discharge cell increase. The lower the pressure is in the glow discharge cell at a fixed discharge power and argon flow rate, the greater the absorbance of sample element is. The optimum conditions are taken from these data and a calibration curve of Cu in low-alloy steel sample is obtained. In this calibration curve, six-jet configuration shows the best analytical results varies as the sample element.