• Journal of the Korean Society of Food Science and Nutrition
• /
• v.42 no.11
• /
• pp.1857-1863
• /
• 2013

Bulgogi sauces containing electron beam-irradiated garlic powder (1%, 3%, and 5%) were used to compare their irradiation status before and after pasteurization ($85^{\circ}C$, 30 min), using a thermoluminescence (TL) analysis by two different laboratories. The sauces with non-irradiated ingredient only provided a background TL glow curve with a maximum peak after $300^{\circ}C$. However, the presence of irradiated ingredient (1 and 10 kGy) was evident through the typical TL glow curves in a temperature range of 150 to $250^{\circ}C$. The concentration of irradiated ingredients showed a greater impact on identification characteristics than their radiation doses. TL ratios ($TL_1/TL_2$) were not able to confirm the results showing evidence of irradiation through the TL glow curve shapes. Pasteurization showed a negligible effect on the key identification parameters and did not change the shape or temperature range of radiation-specific TL glow peak, but reduced TL glow curve intensity. TL glow curve shape with the maximum peak in a temperature range of $150{\sim}250^{\circ}C$ was the most useful characteristic providing information required for confirming the irradiation status.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.8 no.3
• /
• pp.493-497
• /
• 1998

The synthesis of $Sr_{1-x}Eu_xAl_2O_4$ (x=0.005~0.2;mol%) phosphors and its properties of both photoluminescence and long-phosphorescent were investigated as a function of $Eu_2O_3$ composition. The peak wavelengths (520 nm) of phosphorescence spectra were found not to vary with the $Eu_2O_3$ composition (x) of $Sr_{1-x}Eu_xAl_2O_4$ crystals. Single phase of $SrAl_2O_4$ which determined by XRD and PL was obtained with the compositions of x<0.05 mol%. After the removal of light excitation (360 nm), the excellent after-glow characteristics of the phosphorescence were obtained with the $Eu_2O_3$ compositions of x<0.05 mol%, although the after-glow intensities for all phosphors vary exponentially with the times.

• Korean Chemical Engineering Research
• /
• v.49 no.6
• /
• pp.704-709
• /
• 2011

Depolymerization of fucoidan induced by contact glow discharge electrolysis(CGDE) was investigated. To utilize fucoidan as a functional food material after CGDE, organic acids were used as a electrolyte in CGDE process. Experimental results showed that CGDE using organic acid reduced the molecular weight of fucoidan effectively. As electrolyte concentration increased, onset voltage of glow discharge decreased and onset current of glow discharge increased. From the variation of molecular weight of fucoidan with the reaction time, it was demonstrated that the degradation of fucoidan followed a first-order rate law. Molecular weight of fucoidan treated with CGDE using organic acid was about 77 times lower compared to initial fucoidan with little free sulfate.

• Korean Chemical Engineering Research
• /
• v.46 no.5
• /
• pp.886-891
• /
• 2008

Contact glow discharge electrolysis(CGDE) is an unconventional electrolysis where plasma is sustained by D.C. glow discharge between an electrode and the surface of electrolyte surrounding it at high voltage. In this study, the behavior of CGDE in NaCl solution and the depolymerization of fucoidan by CGDE were investigated. After onset of CGDE, increase of voltage enhanced Glow discharge which resulted in low current density and low temperature in NaCl electrolyte. From the variation of molecular weight of fucoidan with the reaction time, it was demonstrated that the degradation of fucoidan followed a first-order rate law. Molecular weight of fucoidan treated with CGDE was about 40 times lower compared to initial fucoidan without content decrease of sulfate and fucos.

• Journal of Ginseng Research
• /
• v.37 no.4
• /
• pp.483-490
• /
• 2013

Gamma-irradiation (0-7 kGy) of ginseng is permitted in Korea for the purpose of microbial decontamination; with strict labeling, traceability and monitoring requirements. An identification study was conducted to determine the photostimulated-luminescence (PSL) and thermoluminescence (TL) properties of gamma-irradiated fresh and white ginsengs cultivated in different areas. Dose- dependent PSL-based screening was possible for white ginseng samples; however, inappropriate results from non-irradiated fresh ginseng samples were obtained, showing intermediate (700 to 5,000) or positive ($T_2$ >5,000, irradiated) PSL counts due to the abundance of minerals on the surfaces of the samples. TL analysis of separated minerals from all non-irradiated samples gave TL glow curves of low intensity with a maximum peak after $300^{\circ}C$. However, well-defined irradiation-specific (high intensity with a maximum peak at about $200^{\circ}C$) glow curves were observed for all the irradiated samples, regardless of their type and origins. TL ratios (first glow curve /second glow curve) were also determined to confirm the irradiated (>0.1) and non-irradiated (<0.1) results. SEM-EDX (scanning electron microscope-energy dispersive X-ray) and XRD (X-ray diffraction) spectroscopic analyses showed that feldspar and quartz minerals were the main source for the typical radiation-specific luminescence properties.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.8
• /
• pp.2140-2156
• /
• 2023

The Wireless Sensor Network (WSN), is constructed out of teeny-tiny sensor nodes that are very low-cost, have a low impact on the environment in terms of the amount of power they consume, and are able to successfully transmit data to the base station. The primary challenges that are presented by WSN are those that are posed by the distance between nodes, the amount of energy that is consumed, and the delay in time. The sensor node's source of power supply is a battery, and this particular battery is not capable of being recharged. In this scenario, the amount of energy that is consumed rises in direct proportion to the distance that separates the nodes. Here, we present a Hybrid Firefly Glow-Worm Swarm Optimization (HF-GSO) guided routing strategy for preserving WSNs' low power footprint. An efficient fitness function based on firefly optimization is used to select the Cluster Head (CH) in this procedure. It aids in minimising power consumption and the occurrence of dead sensor nodes. After a cluster head (CH) has been chosen, the Glow-Worm Swarm Optimization (GSO) algorithm is used to figure out the best path for sending data to the sink node. Power consumption, throughput, packet delivery ratio, and network lifetime are just some of the metrics measured and compared between the proposed method and methods that are conceptually similar to those already in use. Simulation results showed that the proposed method significantly reduced energy consumption compared to the state-of-the-art methods, while simultaneously increasing the number of functioning sensor nodes by 2.4%. Proposed method produces superior outcomes compared to alternative optimization-based methods.

• Korean Journal of Food Science and Technology
• /
• v.32 no.2
• /
• pp.265-270
• /
• 2000

White ginseng powder, permitted to be irradiated in Korea for the purpose of microbial decontamination, was treated with electron beam at doses of $0{\sim}15\;kGy$ for a detection trial whether it is irradiated or not by measuring photostimulated luminescence for whole samples first and then (TL) for the mineral adhering to the samples. PSL values were less than threshold value (700, $T_{1}$) and were negative for nonirradiated samples but more than 5000 $(T_2)$ and were positive for irradiated ones. After PSL measurement mineral was separated from the whole samples using density separation. Mineral of nonirradiated samples was characterized by glow curves which have low intensity and were situated at the high temperature region (about $300^{\circ}C$) by the low level of natural radioactivity. Glow curves of minerals for all irradiated samples were observed at about $200^{\circ}C$. TL ratio by normalization was 0.01 for nonirradiated sample and more than 0.78 for irradiated samples, and it was possible to detect whether white ginseng powders were irradiated or not.

• Food Science and Biotechnology
• /
• v.18 no.2
• /
• pp.374-378
• /
• 2009

Three physical methods, photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance (ESR), have been applied to detect the irradiation treatment for the non- and steamed sesame seed samples. PSL successfully screened the irradiated samples from the non-irradiated control by comparing their photon counts (PCs) with the lower (less than 700 count/60 sec) and upper threshold values (higher than 5,000 count/60 sec). TL signals were still detected in all irradiated samples even after steaming, which was reconfirmed with TL ratios [integrated area of $TL_1$ (the first glow)/$TL_2$ (the second glow)] through re-irradiation step. ESR spectrometry showed that radiation-induced cellulose radicals were detected in all the irradiated samples irrespective of steaming treatment. Identification of the irradiated sesame seeds was possible even after steaming by analyzing PSL, TL, and ESR.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.9 no.3
• /
• pp.315-319
• /
• 1999

Properties of both photoluminescence and long-phosphorescent for Eu, Dy-codoped $SrAl_2O_4$ powder phosphor synthesized by solid reaction method were investigated by PL instrument. Two intense peaks in the emission spectrum measured at 10 K are observed near 450 nm (2.755 eV) and 520 nm (2.384 eV) wavelength, but at 300 K the main peak of 520 nm wavelength is presented. After the removal of light excitation (360 nm), the excellent after-glow characteristic of the phosphorescence were obtained as a result of low decay tiem, although the after-glow intensities of phosphor vary exponentially with the times.

• Journal of Food Hygiene and Safety
• /
• v.25 no.1
• /
• pp.73-78
• /
• 2010

This research was conducted to assess applicability of photostimulated luminescence (PSL) and Thermoluminescence (TL) methods for investigation of infant and young children products, nut, seasoned dried fish, spice, dried fruits, fruit & vegetable, grain and marine products, which are not approved for irradiation in Korea. PSL results show that the photon counts of non-irradiated samples were lower than 700, while those of irradiated samples were higher than 700. In TL measurement, TL ratio of irradiated samples were higher than 0.1 or ones can decrease below 0.1 whereas the temperature range of TL Glow curve was between $150{\sim}250^{\circ}C$. Monitoring result about 8 class of 325 not approved to irradiated foods, photon counts of samples were less than 700, and after re-irradiation TL Ratio ($TL_1/TL_2$) through re-irradiation step at 1 kGy were higher than 0.1 for the all samples. Therefore, these results suggested that PSL and TL measurements were useful detection methods for 8 class food products not approved to irradiation in Korea and all sample (325 cases) were not irradiated when we analysed by PSL and TL methods.