• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.107-107
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• 2009

본 연구에서는 중성빔을 이용한 Atomic Layer Etching(ALET) system을 이용하여 $ZrO_2$의 atomic layer etching mechanism에 대하여 연구하였다. Ar neutral beam irradiation dose와 $BCl_3$ gas pressure의 변화에 따라 $ZrO_2$ etch rate와 RMS roughness를 관찰했을 때, Ar neutral beam irradiation dose이 $1.485{\times}10^{16}atoms/cm^2{\bullet}cycle$ 이상이고 $BCl_3$ gas pressure가 0.15mTorr 이상 일 때 $ZrO_2$ etch rate은 $1.07\;{\AA}/cycle$의 일정한 값에서 유지됨을 확인하였다. 그리고 ALET와 ICP Etcher을 통해 $ZnO_2$를 각각 식각하여 physically or chemically damage를 비교한 결과, ALET가 기존의 ICP Etcher system보다 $ZrO_2$ 식각공정에 대해 적은 damage를 받는 것을 ARXPS를 통해 관찰 하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.2
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• pp.234-238
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• 2001

In order to evaluate their possible subacute toxicity, groups of 40 male and female ICR mice were given to the diet with chickens irradiated up to 30 kGy for four weeks. During the experimental periods, appearance, behavior, mortality, food and water consumption of mice fed irradiated chickens were not affected compared to the control. In urine analysis, hematological as well as in serum biochemical findings, no significant differences were found between the control (non-irradiated) and the irradiated chickens. Although minor changes in biochemical parameters were observed, they were in the normal range and were not dose dependent. Spotty necrosis was found in the male liver administered with 30 kGy irradiated chicken. However, it seems not related with gamma irradiation, because it lacks either the dose dependency and the secondary changes accompanied. Our results indicate that the adverse effect of gamma irradiated chicken can be observed at more than 30 kGy level.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2000.04a
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• pp.139-141
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• 2000

Carboxylic acid group was introduced onto polyethylene (PE) film by the grafting of acrylic acid onto PE film irradiated with electron beam. The grafting Condition such as reaction temperature, additives, total irradiation dose, thickness of PE film, and monomer concentration was examined. The extent of grafting was found to increase with increasing reaction temperature and total irradiation dose. The grafting yield was much enhanced with the addition of both FeSO$_4$ 7H$_2$O and H$_2$SO$_4$.

• 대한두경부종양학회:학술대회논문집
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• 2002.11a
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• pp.254-254
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• 2002

• Journal of Plant Biotechnology
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• v.40 no.3
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• pp.111-124
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• 2013

Research on the basic interaction of radiation with biological systems has contributed to human society through various applications in pharmaceutical, medicine, agriculture and other technological developments. In the agricultural sciences and food technology sectors, the last few decades have witnessed a large number of pertinent works regarding the utilization of radiation for evolution of superior varieties of agricultural crops of economic importance. This review presents general information about the effect of radiation on plant specificity, dose response, and benefits. There has been summarized of the effects observed after exposure and influenced by several factors including plant characteristics and radiation features. We also report on the effect of ${\gamma}$-irradiations on plants, focusing on metabolic alterations, modifications of growth and development and changes in biochemical pathways.

• Journal of Veterinary Clinics
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• v.19 no.1
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• pp.1-6
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• 2002

We evaluated the wholesomeness of fish feeds treated with high-dose radiation. This study examined the safety of fish fed treated with high-dose irradiation (5 kGy) and butylated hydroxyanisole (BHA, 200 ppm). 100 flounder (Paralichthys olivaceus) were grouped into 4 and then the fishes fed the following feeds for 28 days: (1)standard feed; (2)standard feed, treated with BHA; (3)standard feed, irradiated to 5 kGy; (4)standard feed, treated with BHA and irradiated to 5 kGy. Four groups each 10 mice were fed the fish feeds same as (1)-(4) for 14 days. There were no observable differences between fishs fed the irradiated feed and those fed the standard feed with respect to growth, feed consumption, haematology and organ histopathology Parameters. There were no deviations in feed consumtion, haematology and organ histopathology parameters in the experiment of mice. We concluded that there were no irradiation-related effects.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.937-939
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• 2016

In this study, we studied the gamma-radiation effect of fiber Bragg gratings (FBGs) manufactured by array sensors. The array FBGs were fabricated in a different Bragg wavelength using the same commercial Ge-doped fiber and exposed to gamma-radiation up to a dose of about 100 kGy at the dose rate of 113 Gy/min. It was analyzed radiation effects by measuring the radiation-induced change in the temperature sensitivity coefficient and Bragg wavelength shift after irradiation.

• Imaging Science in Dentistry
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• v.33 no.3
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• pp.143-149
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• 2003

Purpose: To investigate the radiosensitivity of the normal human oral keratinocytes (NHOK), and the effect of irradiation on cell cycle and protein expression. Materials and Methods: To evaluate the radiosensitivity of NHOK, the number of colonies and cells were counted after irradiation and the SF2 (survival fraction at 2Gy) value, and the cell survival curve fitted on a linear-quadratic model were obtained. LDH analysis was carried out to evaluate the necrosis of NHOK at 1, 2, 3, and 4 days after 2, 10, and 20 Gy irradiation. Cell cycle arrest and the induction of apoptosis were analyzed using flow cytometry at 1, 2, 3, and 4 days after 2, 10, and 200y irradiation. Finally, proteins related cell cycle arrest and apoptosis were analysed by Western blot. Results: The number of survived cell was significantly decreased in a dose-dependent manner. The cell survival curve showed SF2, α, and β values to be 0.568, 0.209, and 0.020 respectively. At 200y irradiated cells showed higher optical density than the control group. After irradiation, apoptosis was not observed but G2 arrest was observed in the NHOK cells. 1 day after 10 Gy irradiation, the expression of p53 remained unchanged, the p2l/sup WAF1/Cipl/ increased and the mdm2 decreased. The expression of bax, bcl-2, cyclin B1, and cyclin D remained unchanged. Conclusion: These results indicate that NHOK responds to irradiation by G2 arrest, which is possibly mediated by the expression of p21/sup WAFl/Cipl/, and that cell necrosis occurs by high dose irradiation.

• Journal of Veterinary Clinics
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• v.18 no.2
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• pp.146-151
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• 2001

This study was carried out to find if the X-irradiation being used for clinical diagnosis during pregnancy would affect fetal development and cause fetal malformation in rats or not. To determine the dose and irradiation frequency of X-irradiation and gestation period by which fetal development would be affected when irradiated during pregnancy, seventy-two Sprague Dawley female rats (8 weeks old) were used for the experiment and grouped into three according to different gestation period of 5-8 days, and 6-12 days of gestation. Experimental rats were irradiated on the daily irradiation conditions of 40, 60, 80 kvp(kilo volt peak), 150 mA(milliampere), 0.25 sec and 4 times/day for both 5-8 days and 10-13 days of gestation, and 100 kvp, 100 mA, 2 min. and 4 times/day for 6-12 days of gestation. Rats were put in a small dark box when irradiated, which animals were sacrificed on the 20th day of gestation and mean litter size, fetal body weight, fetal crown-rump length(CRL) were investigated along with pathological findings. 1. Litter size were significantly decreased in the rats which were irradiated by both 60 and 80 kvp during 5 to 8 days of gestation and by 100 kvp during 6-12 days of gestation compared to those from the control rats(p<0.05) 2. Fetal body weight was significantly decreased in the fetus from the rats which were irradiated by both 60-80 kvp during 5-8 days of gestation and by 100 kvp during 6-12 days of gestation compared to those from the control rats(p<0.05). 3. There was no significant difference of fetal crown-rump length between all the experimental rats and the controls. 4. Fetal absorption, fetal death, and fetal malformation were not observed in the fetus form the rats irradiated by 40-80 kvp during 5-8 and 10-13 days of gestation, however, the pathological findings were found in those from the rats irradiated by 100 kvp during 6-12 days of gestation. 5. The harmful effect of x-irradiation on fetal development was estimated to occur when irradiated during 5-8 days of gestation. These results indicated that even X-irradiation for clinical diagnosis could affect fetal development in the early embryonic stage and when the fetus were exposed to frequent and prolonged x-irradiation with over dose.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.289-294
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• 2008

The influence of gamma irradiation with low doses (0.5, 1.0, and 1.5 kGy) on the meat quality of chicken breast was determined for 6 days of storage at $4^{\circ}C$. The pH of irradiated chicken was lower than that of the control at day 1 (p<0.05), while no difference was found among irradiation at different doses. Drip loss was higher in irradiated chicken with doses of 0.5 and 1.0 kGy compared to the control at day 1 and day 3 (p<0.05). Lightness (L) at day 1 and day 6 was increased due to irradiation (p<0.05). Redness (a) increased with irradiation doses of 1.0 and 1.5 kGy at day 1 and day 3 (p<0.05). However, no significant differences were found in yellowness (b). The number of aerobic plate count of irradiated chicken during storage was significantly lower than the control (p<0.05). E. coli and coliforms were not detected after irradiation at any dose. Also, irradiation doses of 1.0 and 1.5 kGy significantly reduced volatile basic nitrogen (VBN) and 2-thiobarbituric acid reactive substances (TBARS) values compared to the control during storage (p<0.05). These results suggest that low dose gamma irradiation can be useful to extend the shelf life of chicken breast during cold storage.