• BMB Reports
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• v.35 no.6
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• pp.590-594
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• 2002

To elucidate the effect of gamma-irradiation on the molecular properties of myoglobin, the secondary and tertiary structures, as well as the molecular weight size of the protein, were examined after irradiation at various irradiation doses. Gamma-irradiation of myoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains. A SDS-PAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation, due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid protected against the degradation and aggregation of proteins by scavenging oxygen radicals that are produced by irradiation. A circular dichroism study showed that an increase of the irradiation decreased the a-helical content of myoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation increased the emission intensity that was excited at 280 nm.

• Journal of Acupuncture Research
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• v.22 no.5
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• pp.121-132
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• 2005

Objectives : The purpose of study was to compare and analyze the effect of the Intravascular Laser Irradiation Therapy and the Exterior vascular Laser Irradiation Therapy on Hypercholesterolemia. Methods : The 73 Sam-se-han-bang hospital patients who were irradiated to the Intravascular Laser and the 57 Sam-se-han-bang hospital patients who were irradiated to the Exterior vascular Laser were the study group. They had the treatment two or three times a week, and had checked total cholesterol before and after the ten times irradiation therapy. Results : Both the Intravascular Laser Irradiation Therapy and the Exterior vascular Laser Irradiation Therapy were effective on decreasing total cholesterol. The effect on decreasing total cholesterol was more definite at the abnormal group than the border line group, and the border line group than the normal group. The effect on decreasing total cholesterol was more definite at the Exterior vascular Laser Irradiation Therapy than the Intravascular Laser Irradiation Therapy, but this result was unavailable in the statistics. Conclusion : Both the Intravascular Laser Irradiation Therapy and the Exterior vascular Laser Irradiation Therapy had available effect on decreasing total cholesterol.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.220-220
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• 2009

In case of favourable irradiation conditions, the ratio of irradiation to the total irradiation went up and then the irradiation increased in the area with high angle of inclination. The study showed that on a clear day with the irradiation of more than $800[W/m^2]$, the pattern of alternating current power change in the fixed system was similar with that in the single-axis tracker. On the contrary, in case of unfavourable irradiation conditions, the ratio of diffuse irradiation to the total irradiation went up and then the horizontal irradiation increased. In the demo system, the fixed system, the single-axis tracker and the dual-axis tracker all had low generation power and similar generation pattern with each other. The study showed the generation power varied with the irradiation in the fixed system, while in the single-axis tracker and the dual-axis tracker, the amount of the generation power variation was much more than the irradiation variation. The demo system was operated from 11:00 AM to 2:00 PM for generating power, during which time, 46[%] to 56[%] of the total generation power was produced. In this study. the generation power was increased by 147[%] in the fixed system, by 136[%] in the single-axis tracker, and by 164[%] in the dual-axis tracker, and the pattern of generation power was similar with the generation power variation in the situation where the irradiation increased by 140[%] in the spring with plenty of insolation. The alternating current power was more sensitive to variation of the irradiation than to that of the surface temperature of a module. The variation of the irradiation had a more positive effect on the generation power than the type of array.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.46-48
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• 2009

This paper aims to investigate generation conditions necessary for the most efficient generation by measuring electricity power under various irradiation conditions, since the photovoltaic generation system has high costs and low efficiency. In addition, because the irradiation varies hourly, daily, monthly, and yearly, the research on the irradiation necessary for photovoltaic generation was carried out by analyzing the pattern o( Bower under various irradiation conditions. Also, after measuring the daily variations of irradiation and generation power, the monthly accumulated irradiation and monthly accumulate power which had the most generation power were investigated and the pattern of the annual generation power was analyzed. The results of this study are as follows. As for the relationship between the photovoltaic generation system and the irradiation, the generation power increased with the irradiation and when the irradiation was more than 600 $[W/m^2]$ the generation power amounted to more than 100 [Wh] as the resonable result.

• Nuclear Engineering and Technology
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• v.46 no.4
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• pp.501-512
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• 2014

HANARO is a multipurpose research reactor located at the Korea Atomic Energy Research Institute (KAERI). Since the commencement of its operation in 1995, various neutron irradiation facilities, such as rabbit irradiation facilities, fuel test loop (FTL) facilities, capsule irradiation facilities, and neutron transmutation doping (NTD) facilities, have been developed and actively utilized for various nuclear material irradiation tests requested by users from research institutes, universities, and industries. Most irradiation tests have been related to national R&D relevant to present nuclear power reactors such as the ageing management and safety evaluation of the components. Based on the accumulated experience as well as the sophisticated requirements of users, HANARO has recently supported national R&D projects relevant to new nuclear systems including the System-integrated Modular Advanced Reactor (SMART), research reactors, and future nuclear systems. This paper documents the current state and utilization of irradiation facilities in HANARO, and summarizes ongoing research efforts to deploy advanced irradiation technology.

• Preventive Nutrition and Food Science
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• v.6 no.4
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• pp.253-256
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• 2001

Irradiation of food is not only used for sanitation purposes but can be used for processing techniques to reduce or eliminate toxic or undesirable compounds on food. Irradiation wag effective to reduce the allergenicity of food by modification of the structure of proteins causing allergy reactions. Volatile N-nitrosmaine was reduced or eliminated by irradiation in the model system study and the breakdown products by irradiation did not recombine under human stomach conditions (pH 2,3, and 4,37$^{\circ}C$). The possibility of residual chlorophyll b reduction by irradiation was also found, and the model study indicated that irradiation be used to destroy chlorophyll b, resulting in protection from photooxidation in oil without acceleration of lipid oxidation during irradiation. In this paper, several on-going research projects for the application of food irradiation as a new processing technique are introduced, including reduction of food allergens, breakdown of volatile N-nitrosamine and residual chlorophyll b.

• Macromolecular Research
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• v.11 no.5
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• pp.352-356
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• 2003

The objectives of this study were to investigate the influence of gamma irradiation for sterilization on poly(D,L-lactide-co-glycolide) (PLGA) with different molecular weight and the effect of gamma irradiation on the release behavior of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU, carmustine) from PLGA wafer with various irradiation doses. The effect of gamma irradiation on PLGA was evaluated by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and electron paramagnetic resonance (EPR). The weight average molecular weight (M$_{w}$) and glass transition temperature (T$_{g}$) of PLGA decreased after gamma irradiation. The extent of M$_{w}$ reduction was dependent on irradiation dose and PLGA molecular weight. Using EPR spectroscopy, we successfully detected gamma irradiation induced free radicals in PLGA. The gamma irradiation increased the release rate of BCNU from PLGA wafer at applied irradiation doses except 2.5 Mrad of irradiation dose in this study.study.

• Proceedings of the KIEE Conference
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• 2009.04a
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• pp.43-45
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• 2009

In case of favourable irradiation conditions, the ratio of irradiation to the total irradiation went up and then the irradiation increased in the area with high angle of inclination. The study showed that on a clear day with the irradiation of more than 80$[W/m^2]$, the pattern of alternating current power change in the fixed system was similar with that in the single-axis tracker. On the contrary, in case of unfavourable irradiation conditions, the ratio of diffuse irradiation to the total irradiation went up and then the horizontal irradiation increased. In the demo system, the fixed system, the single-axis tracker and the dual-axis tracker all had low generation power and similar generation pattern with each other. The study showed the generation power varied with the irradiation in the fixed system, while in the single-axis tracker and the dual-axis tracker, the amount of the generation Power variation was much more than the irradiation variation. The demo system was operated from 11:00 AM to 2:00 PM for generating power, during which time, 46[%] to 56[%] of the total generation power was produced. In this study, the generation power was increased by 147[%] in the fixed system, by 136[%] in the single-axis tracker, and by 164[%] in the dual-axis tracker, and the pattern of generation power was similar with the generation power variation in the situation where the irradiation increased by 140[%] in the spring with plenty of insolation. The alternating current power was more sensitive to variation of the irradiation than to that of the surface temperature of a module. The variation of the irradiation had a more positive effect on the generation power than the type of array.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1994.03a
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• pp.35-49
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• 1994

Based on the safety of irradiated foods which was demonstrated from the toxicological, microbiological and nutritional points of view, irradiation has been identified as a viable technology for food preservation and processing, having a potential both of reducing storage losses by controlling spoilage organisms, sprouting and ripening, and of improving hygienic quality of raw and processed products. Research and development over decades in the field of food irradiation have led to the regulatory approval in 37 countries and of them 25 countries including Korea are commercially utilizing food irradiation process. Although progress towards acceptance of food irradiation by the industry is slow, actual market trials have shown that once consumers have understood this technology, they are willing to buy irradiated foods. Considering recent advances in food irradiation and restrictions in the use of chemical fumigants, it is expected that food irradiation is in the process of "taking off". This paper deals with up-to-date progress in food irradiation with particular reference to domestic activities in legislation, consumer perception, commercialization, and potential applications in the food industry.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.135.1-135
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• 2003

To elucidate the effect of gamma-irradiation on the molecular properties of hemoglobin, the secondary, tertiary structure, and the molecular weight size of the protein were examined after irradiation at 0.5, 1, 5, and 10 kGy. Gamma-irradiation of hemoglobin solutions caused the disruption of the ordered structure of the protein molecules, as well as degradation, cross-linking, and aggregation of the polypeptide chains. A SDS-PAGE study indicated that irradiation caused initial fragmentation of the proteins and subsequent aggregation due to cross-linking of the protein molecules. The effect of irradiation on the protein was more significant at lower protein concentrations. Ascorbic acid decreased the degradation and aggregation of proteins by scavenging oxygen radicals that were produced by irradiation. A circular dichroism study showed that irradiation decreased the helical content of hemoglobin with a concurrent increase of the aperiodic structure content. Fluorescence spectroscopy indicated that irradiation decreased the emission intensity that was excited at 280 nm.