• 한국식품저장유통학회지
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• 제14권4호
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• pp.408-413
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• 2007

본 연구는 감마선 조사된 분말수정과의 저장 중 관능적 품질특성 변화 및 돌연변이원성을 평가하고자 실시되었다. 미생물 분석결과 멸균을 위한 최소선량은 약 4.5 kGy인 것으로 확인되었다. 감마선 조사된 시료들의 관능평가를 실시한 결과 조사선량이 증가할수록 모든 평가항목에 감소하는 경향이었으며, 색도의 변화를 평가한 결과 감마선 조사선량이 증가함에 따라 명도($L^*$)는 유의적으로 증가하고 적색도($a^*$) 및 황색도($b^*$)는 유의적으로 낮아지는 경향을 나타내었다. S. typhimurium TA98, TA100을 이용한 돌연변이원성 실험에서 감마선 조사군의 전 용량단계에서 음성대조군과 동일한 수준의 돌연변이 집락수를 보여 돌연변이 유발성이 없는 것으로 나타났다.

• 방사선산업학회지
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• 제5권2호
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• pp.169-173
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• 2011

This study investigated the effect of gamma irradiation on immune enhancing activity of Chaga mushroom extract (CME). CME was prepared by hot water extraction at $70^{\circ}C$ for 4 hours and lyophilized. Lyophilized CME powder was dissolved with deionized water at $10mg\;ml^{-1}$ and then irradiated at the doses of 10, 30 and 50 kGy by cobalt 60 gamma irradiator. The gamma-irradiated and non-irradiated CME were treated into the splenocyte separated from mouse. Cell proliferation and cytokine production of the immune cells were increased by gamma-irradiated CME and these increases were more prominent when CME was irradiated at higher doses. Therefore, it is considered that gamma irradiation can be an effective method for improvement of the immunomodulating activity Chaga mushroom extract.

• 방사선산업학회지
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• 제2권1호
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• pp.27-34
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• 2008

곡류 및 전분류, 채소 및 과일류, 생선, 육류 및 콩류 및 향신류 등의 시료에 대한 감마선 조사에 의한 검지 특성을 물리적 검지 방법인 photostimulated luminescence (PSL), electron spin resonance (ESR) 및 thermoluminescence (TL) 분석을 통하여 검지 가능성을 확인하였다. PSL 분석 결과 곡류 및 전분류 시료군 가운데 옥수수 전분, 소맥분과 채소 과일류 시료군의 미역 등의 시료는 비 조사군(negative, ${\leq}700$)으로 판정되었으며, 생선, 육류 및 콩류 시료군의 흰 강낭콩 추출분말 및 향신료 시료군의 칠리 파우더를 포함한 9종의 시료는 감마선 조사군(positive, ${\geq}5000$)으로 판정되었다(전체 시료의 3.2%). 이외에 39종의 시료군에서는 방사선 조사 가능성이 있는 700~5,000 범위의 photon counts (intermediate)를 나타내었다(전체 시료의 15.6%). 이들 시료에 대한 TL 분석 결과, 칠리 파우더를 비롯한 미네랄이 분리된 5종의 시료에서는 $150{\sim}250^{\circ}C$ 전후에서 TL glow curve ($TL_1$)을 나타내어 감마선 조사 여부의 확인이 가능하였다. ESR 분석 결과 2차 검증 시료군에서 방사선 유래 특이적인 signal이 관찰되지 않아서 추출물 시료에는 ESR 분석법의 적용이 불가능한 것으로 나타났다.

• 한국식품영양과학회지
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• 제37권2호
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• pp.239-244
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• 2008

본 연구에서는 고선량 감마선 조사에 의한 김치의 탈색, 이미 및 이취의 발생을 억제하고 품질을 개선하기 위해 파프리카 색소와 김치향을 첨가하였다. 첨가물의 최적 첨가량 결정을 위한 관능평가 결과, 파프리카 색소와 김치향의 최적 첨가량은 각각 0.2%로 결정되었다. 김치의 적색도와 capsanthin 함량은 25 kGy의 감마선 조사로 인해 감소하였으나 0.2%의 파프리카 색소를 첨가한 후 적색도와 capsanthin 함량은 증가하였고 $35^{\circ}C$, 30일의 저장기간 동안 적색도는 유지되었다. 또한 관능평가 결과로부터 파프리카 색소 및 김치향이 감마선 조사에 의한 김치의 관능적 품질 저하를 방지하는데 효과적임을 알 수 있었다. 따라서 파프리카색소, 김치향 첨가 및 고선량 감마선 조사의 병용처리는 멸균된 김치의 관능적 품질을 개선하기 위한 효과적인 방법으로 판단되었다.

• 한국의학물리학회지:의학물리
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• 제29권2호
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• pp.73-80
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• 2018

Accelerated partial breast irradiation (APBI) is a new treatment delivery technique that decreases overall treatment time by using higher fractional doses than conventional fractionation. Here, a quantitative analysis study of CyberKnife-based APBI was performed on 10 patients with left-sided breast cancer who had already finished conventional treatment at the Inha University Hospital. Dosimetric parameters for four kinds of treatment plans (3D-CRT, IMRT, VMAT, and CyberKnife) were analyzed and compared with constraints in the NSABP B39/RTOG 0413 protocol and a published CyberKnife-based APBI study. For the 10 patients recruited in this study, all the dosimetric parameters, including target coverage and doses to normal structures, met the NSABP B39/RTOG 0413 protocol. Compared with other treatment plans, a more conformal dose to the target and better dose sparing of critical structures were observed in CyberKnife plans. Accelerated partial breast irradiation via CyberKnife is a suitable treatment delivery technique for partial breast irradiation and offers improvements over external beam APBI techniques.

• Preventive Nutrition and Food Science
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• 제7권1호
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• pp.52-56
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• 2002

This study was conducted to evaluate the possibility of gamma radiation for reducing egg allergies through the observation of conformational and allergenic changes of egg ovomucoid (OM) in basic pH conditions. An OM solution of 2.0 mg/mL was individually prepared with different pH conditions, pH 7.0, 9.0 or 10.0, and was irradiated with the absorbed dose of 10 kGy. Irradiated OM solutions were tested by Ci-ELISA formatted with egg-hypersensitive patients'IgE. Binding abilities of IgE to OM in irradiated solution decreased with the increase of pH. Turbidity of the solution highly increased by irradiation and the increase of pH. A yellowish color was observed in the irradiated OM solution of basic condition. Coagulation of OM by irradiation decreased with the increase of pH, when observed by SDS-PAGE.

• Radiation Oncology Journal
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• 제12권2호
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• pp.143-150
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• 1994

The damage which radiation produces in tissues such as the lungs can be discussed at the molecular, biophysical, cellular, and organ levels. The cellular effects of irradiating the lungs are related to the histologic and clinical sequelae. In the present study the right lung of rabbits were exposed to single dose of 20 Gy of X-irradiation. Animals from each group were sacrificed monthly for 6 months postexposure. Sections of lung were examined by light microscopy(LM) and by transmission electron microscopy(TEM). Multiple exudative lesions were seen at 2 months after the 20Gy irradiation,and they progressed to a proliferative and then reparative fibrotic lesion by 6 months. Changes in epithelial lining of lung components, particulary the presence of type II pneumocytes were found by both LM and TEM. Capillary endothelial damages were less pronounced. The possible implication of cellular components in radiation pneumonitis and fibrosis is discussed.

• Carbon letters
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• 제16권1호
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• pp.41-44
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• 2015

We report the preparation of sulfonated reduced graphene oxide (SRGO) by the sulfonation of graphene oxide followed by radiation-induced chemical reduction. Graphene oxide prepared by the well-known modified Hummer's method was sulfonated with the aryl diazonium salt of sulfanilic acid. Sulfonated graphene oxide (SGO) dispersed in ethanol was subsequently reduced by ${\gamma}$-ray irradiation at various absorbed doses to produce SRGO. The results of optical, chemical, and thermal analyses revealed that SRGO was successfully prepared by ${\gamma}$-ray irradiation-induced chemical reduction of the SGO suspension. Moreover, the electrical conductivity of SRGO was increased up to 2.94 S/cm with an increase of the absorbed dose.

• Nuclear Engineering and Technology
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• 제45권3호
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• pp.311-322
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• 2013

High-Cr martensitic steel HT-9 is one of the candidate materials for advanced nuclear energy systems. Thanks to its excellent thermal conductivity and irradiation resistance, ferritic/martensitic steels such as HT-9 are considered for in-core applications of advanced nuclear reactors. The harsh neutron irradiation environments at the reactor core region pose a unique challenge for structural and cladding materials. Microstructural and microchemical changes resulting from displacement damage are anticipated for structural materials after prolonged neutron exposure. Consequently, various irradiation effects on the service performance of in-core materials need to be understood. In this work, the fundamentals of radiation damage and irradiation effects of the HT-9 martensitic steel are reviewed. The objective of this paper is to provide a background introduction of displacement damage, microstructural evolution, and subsequent effects on mechanical properties of the HT-9 martensitic steel under neutron irradiations. Mechanical test results of the irradiated HT-9 steel obtained from previous fast reactor and fusion programs are summarized along with the information of irradiated microstructure. This review can serve as a starting point for additional investigations on the in-core applications of ferritic/martensitic steels in advanced nuclear reactors.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2009년도 추계 학술발표
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• pp.128-129
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• 2009