• Journal of Radiation Industry
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• v.17 no.4
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• pp.533-542
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• 2023

We developed an emergency national manual for preservation of cultural heritage using irradiation disinfection technic under flood disaster. And we examined its practicality with a critical radiation dose on fungi that occur at water-logged event in order to prevent fungal damage that occurs during submersion. The X-ray irradiation for this experiment was conducted at the Production Technology Research Institute located in Yeongcheon, Gyeongsangbuk-do. A disinfection critical dose of 12 kGy was selected for two types of fungi known to spread rapidly and are resistant to radiation to submerged cultural properties, and this experiments were conducted by setting a target dose of 12kGy at 8.37mA at 5MeV. Under the above conditions, only continuity of irradiated samples were completely disinfected. This suggests that continuity of irradiation is important for fungal disinfection.

• Journal of Radiation Industry
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• v.7 no.1
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• pp.1-5
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• 2013

Photostimulated luminescence (PSL) and thermoluminescence (TL) analyses were applied to identify the cookie molds mixed with 2 mg of 10 kGy-irradiated minerals according to cookie processing methods and sonication time (0~60 min) for mineral separation. PSL analysis showed that photon counts of cookies, dried or baked, ranged intermediate levels between the lower and upper threshold (700~5,000 counts/60 s), thereby showing its unsuitablility for screening of irradiated cookie. The TL glow curve intensities, measured according to mineral separation time (5, 10, 20, 40 and 60 mins) from the cookies using a sonicator, were high enough to identify irradiation status and significantly increased with the time in dried cookies. Those of baked cookies, however, were relatively low and not linearly increased with the time, but still possible to identify them (p<0.05).

• Journal of Radiation Industry
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• v.8 no.2
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• pp.89-95
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• 2014

This study was conducted to determine the optimal dose of gamma-ray on the growth and nucleus DNA damage for mutation breeding in licorice. Gamma-rays irradiated to dry seeds with various doses (0 to 1000 Gy). Significant decreases in germination rate (%), survival rate (%) and growth characteristics (plant height, number of leaves, root length and fresh weight) were observed by dose of increased. $LD_{50}$ (lethal dose) was approximately 400 Gy to 500 Gy. Also, reduction doses ($RD_{50}$) of plant height, number of leaves, root length and flash weight were 428 Gy, 760 Gy, 363 Gy and 334 Gy, respectively. It is supplest that the optimal dose of gamma irradiation for licorice mutation induction might be about 400 Gy in this study. We also conducted comet assay to observe nucleus DNA damage due to gamma irradiation. In comet assay, a clear difference was identified over 300 Gy treatments. With increasing doses of gamma-ray in the range of 100 to 1000 Gy, the rate of head DNA was decreased significantly from 92.88% to 73.09%. Tail length(${\mu}m$) was increased as the dose of increased over 300 Gy. Growth characteristics (Germination rate, Survival rate, plant height, number of leaves, root length and fresh weight) were highly negatively ($P{\leq}0.01$) correlated with dose. While the tail length was highly positively ($P{\leq}0.01$) correlated with dose.

• Journal of Radiation Industry
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• v.18 no.3
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• pp.235-240
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• 2024

Electron beam technology has recently attracted attention as one of the powerful air pollution control methods. In this study, methyl mercaptan decomposition by electron beam in a continuous gas flow system was studied. To this, the effect of gas flowrate, which is one of important operating variables in the continuous gas flow electron beam process, on methyl mercaptan treatment efficiency was studied. In particular, the treatment efficiency and the reaction kinetics of methyl mercaptan decomposition were compared when calculated based on the absorbed dose and when calculated based on the current intensity of electron beam. When based on the electron beam absorbed dose, the treatment efficiency and 1st-order reaction constant increased as the gas flowrate was increased, contrary to the trends in general chemical reactions. However, when based on the current intensity, the treatment efficiency and 1st-order reaction constant increased as the gas flowrate was decreased, which can be theoretically explained. This is due to the fact that the current intensity increased as the gas flowrate was increased, resulting in improved the electron beam treatment efficiency. In conclusion, it is necessary to consider not only the absorbed dose but also the current intensity of electron beam in order to explain the results of reaction efficiencies and kinetics in the continuous flow electron beam gas treatment process.

• Nuclear industry
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• v.7 no.7 s.53
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• pp.72-75
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• 1987

원자력발전의 고가동율에 관해서는 기기$\cdot$부품의 재료개선이 큰 역할을 하고 있다. 또 장래의 경수로 고도화 추진에도 신소재 개발은 그중 핵심기술이 되고 있다. 동 기술의 연구개발은 어떻게 추진되고 있는가. 본고에서는 일본원자력용차세대기기개발연구소(ANERI)가 최근 종합한 자료에서 선진 각국에서의 경수로 기기$\cdot$부품에 대한 신소재 적용 현황을 소개한다.

• 전기의세계
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• v.10
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• pp.100-103
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• 1963

본고에서는 원자력발전소의 중요한것 몇가지를 소개함으로서 타 연구소의 운영상 참고자료를 제공코저 하며 당연구소의 활동개황을 소개함으로써 한국의 과학발전을 위한 원자력연구소의 효과적인 이용과 타연구기관 및 산업체와의 협조를 촉진코저 한다.

• Journal of Radiation Industry
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• v.3 no.1
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• pp.19-24
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• 2009

The citrus fruits were irradiated at different doses (25~200 kGy) to remove pesticides such as diuron, dichlorbenil, trifluralin, dimetoate, chlorothalonil, fenitrothion, bromacil, phenthoate and norflurazon, and the rates of degradation were detected by using gas chromatography electron capture detector (GC-ECD). The limit of detection (LOD) was in the range of 0.007~0.105 ppm. The limit of quantification (LOQ) was in the range of 0.024~0.352 ppm, and the recoveries of 9 pesticides were in the range of 71.5~106.5%. The results demonstrated that the ${\gamma}$-irradiation was effective method to remove pesticides such as diuron, dichlorbenil, trifluralin, dimetoate, chlorothalonil, fenitrothion, and norflurazon. However, the bromacil and phenthoate showed lower removal rates in the rate of 40.5 and 54.8%, respectively, at 200 kGy irradiation.

• Journal of Radiation Industry
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• v.5 no.1
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• pp.63-67
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• 2011

A comparative experiment was conducted to compare the effects of persulfate with gamma radiation on the disinfection efficiencies against Escherichia coli K12. The microorganism used for the disinfection experiments were prepared by transferring a bacterial stock culture into a 50 ml nutrient broth an incubating for 24 hrs at $37^{\circ}C$. The initial concentration of the harvested culture was approximately $10^7$ to $10^9CFU\;ml^{-1}$. The culture solution was irradiated at different absorbed doses of 0.1, 0.2, 0.3, 0.4, 0.5, 0.7, and 1 kGy, respectively. The disinfection efficiency of persulfate with gamma radiation of 0.3 kGy against Escherichia coli K12 was 97.2% and while the gamma radiation only was 90.01% at 0.3 kGy. Therefore, it could be thought that addition of persulfate in the disinfection of Escherichia coli K12 can enhance the disinfection efficiency when it is used together with gamma radiation.

• Journal of Radiation Industry
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• v.5 no.3
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• pp.273-277
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• 2011

This study evaluated the cytotoxicity and anti-inflammatory activities of natural herbal extracts including Houttuynia cordata and Eucommia ulmoides against human mast cell (HMC-1). Houttuynia cordata (HC) and Eucommia ulmoides(EU) were extracted with distilled water (at $75^{\circ}C$) and then freeze-dried for 5 days. Finally, the mixture of HC and EU were sterilized by ${\gamma}$-rays irradiation. Cytotoxicity of the mixture against HMC-1 cell was measured using cell counting kit-8 (CCK-8) assay. In addition, inflammatory mediator cytokines such as TNF-${\alpha}$, IL-6 and IL-8 were evaluated by ELISA kit on the HMC-1 cells with calcimycin A23187 and phorbol 12-myristate 13-acetate (PMA). The results showed that mixture of HC and EU had no cytoxicity and reduced TNF-${\alpha}$, IL-6, IL-8 response on HMC-1 cells.

• Journal of Radiation Industry
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• v.9 no.3
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• pp.119-126
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• 2015

In Shinjeong-dong of Jeongeup, there are three government-supported research institutes and an RFT industrial complex which is currently being established. Increased human activities can affect flora and fauna as a man-made pressure onto the region. As a baseline study, status of exotic plants was investigated prior to a full operation of the RFT industrial complex. A total of 54 species and 1 variety of naturalized or introduced plants were found in the study area. Among them, three species (Ambrosia artemisifolia var. elatior, Rumex acetocella and Aster pilosus) belong to 'nuisance species', and four species(Phytolacca americana, Iopomoea hederacea, Ereechtites hieracifolia and Rudbeckia laciniata) to 'monitor species' designated by the ministry of Environment. Some of naturalized trees and plants were intentionally introduced in this area, while others naturally immigrated. Physalis angulata seemes to immigrate in the study area in the form of mixture with animal feeds as its distribution coincided with the transportation route of the animal feeds. Liquidambar styraciflua is amenable to the ecological investigation on the possible expansion of the species to the nearby Naejang National Park as its leave shape and autumn color are very similar to those of maple trees. The number of naturalized plants around the RFT industrial complex will increase with an increase in floating population, in human activities in association with constructions of factories and operations of the complex. The result of this study provides baseline data for assessing the ecological change of the region according to the operation of the RFT industrial complex.