• Journal of Radiation Industry
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• v.6 no.2
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• pp.159-164
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• 2012

Bacterial cellulose (BC) is generated from citrus gel by Gluconacetobacter hansenii TL-2C. BC has good properties such as high-burst pressure, high-water contact and the ultrafine highly nanofibrous structure of mimic natural extracellular matrix (ECM) for tissue engineering. In this study, acrylic acid (AAc) was grafted onto BC surfaces under aqueous conditions using gamma-ray irradiation, and then immobilized gelatin onto AAc-g-BC. The characterization of scaffolds was performed by scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), toluidine blue O (TBO) assay. Morphology of gelatin and AAc incorporation onto BC nanofibers did not changed. Our study suggests that gelatin-immobilized BC nanofibers scaffold has a potentiality to fabricate 3D nanofibrous scaffolds for tissue engineering.

• Journal of Radiation Industry
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• v.5 no.2
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• pp.145-149
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• 2011

Poly(butylenes terephthalate) have made large strides in applications of injection, extrusion, and molding material due to their excellent thermal resistance and appropriate mechanical properties. However, PBT was not hard polymer but a soft polymer which caused low absorption of external energy and the defect of being easily broken with the strong impact. Thus, the electron beam irradiation was carried out over a range of irradiation doses from 100 to 1,000 kGy for enhancing the properties. The decreases of $T_m$, $T_c$, and enthalpy were observed as increasing the absorbed dose in the results of DSC analysis. The improvement in the impact strength of PBT was clearly observed as the absorbed dose was increased. This was probably due to the 3-dimensional network structures, resulting in increasing the absorption of impact energy. In addition, the wear properties had increased at higher than 300 kGy. The negative deviation of weight loss confirmed the improvement of the wear properties of PBT, as evidenced by SEM observation on the wear surfaces.

• Journal of Energy Engineering
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• v.8 no.1
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• pp.59-66
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• 1999

원자력발전의 고유한 문제점을 해결할 수 있는 새로운 집적폐회로형 AMBIDEXTER 원자력시스템 개념을 제안하였다. 이 복합시스템은 일체형 원자로를 중심으로 열/에너지 변환회로와 방사선/물질 수송회로를 서로 독립적으로 구성하므로 최소 방사선 위험부담 아래서 원자력에너지의 잇점을 극대화하는 설계이다. 특히 방사선/물질 수송회로로부터 분리된 고준위 방사성 폐기물에서 고부가가치 동위원소나 방사선원을 선별적으로 용이하게 추출, 활용할 수 있다. 원자로 계통은 얇고 큰 Hastelloy 합금 원자로용기 내부를 노심, 침니, 열교환기, 다운캄어 및 입구플레넘 콤파트먼트로 분할하여 배관이나 벨브관이 없으므로 기기파손으로 인한 방사성물질의 대량 외부 누출은 불가능하다. Th/233U 용융염핵연료의 핵물리 및 열수력학적 특성을 살려 AMBIDEXTER 노심의 핵적 자활성 설계에 융통성을 부여하는 변성핵연료주기를 도입하면 핵연료자원의 공급 안정화나 핵확산방지의 투명성 제고에 큰 효과가 있다. AMBIDEXTER 설계연구에 관련된 핵심기술들은 일찍이 미국 ORNL에서 시작한 MSR 프로그램을 통해 개발되어 이미 대부분 상용화하고 있기 때문에 현재 추진 중인 250 MWth급 원형로 모듈의 개념개발에서는 주로 시스템 통합에 관한 문제들이 중점적으로 다루어진다.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.183-190
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• 2013

Mistletoe (Viscum album) has been widely used as a functional food material for various therapeutic purposes from ancient time. In this study, we examined anti-diabetic and cytotoxic activities of heated-treated mistletoe and the effects of gamma-irradiation on its activities. Heat-treated mistletoe extract was prepared by heating during different time (3, 6, 9 and 12 h) and gamma-irradiated with different doses of 0, 10, 30, 50, 70 and 100 kGy. Heat-treated mistletoe extracts showed a concentration-dependent cytotoxicity on rat insulinoma RINm5F cells and the effect was gradually decreased as heating time increased up to 12 h. 12 h heat-treated extract was no cytotoxic. Gamma-irradiation enhanced the reduction of heat-treated mistletoe-induced cytotoxicity and the decreasing effect was an irradiating dose-dependent. In particular, all of 70 kGy irradiated and heat-treated mistletoe extracts did not showed the cytotoxicity and the effect was comparable to 12 h heat-treated mistletoe extract. Among those extracts, 3 h heat-treated mistletoe extract gradually increased the insulin secreting activity by gamma-irradiation and the effect was the best at 70 kGy, whereas 12 heat-treated extract was no effect. On the test of ${\alpha}$-glucosidase inhibitory activity, 3 h heat-treated mistletoe extract showed the concentration dependent effects and gamma-irradiation induced more activity at 70 kGy, compared to non-irradiated 3 h and 12 h heated mistletoe extracts. These results suggest that the combination of heat treatment and gamma-irradiation might be more effective than only heat-treatment for improving the anti-diabetic activity of mistletoe extract and reducing its cytotoxicity.

• Journal of Radiation Industry
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• v.5 no.1
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• pp.75-80
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• 2011

This study was to determine the microbiological safety and tensile strength of gammairradiated porcine tendon for the development of safe xenografts. Escherichia coli and Bacillus subtilis were used as model pathogens and inoculated as $10^6{\sim}10^7log$ colonies forming unit $(CFU)g^{-1}$. As model virus from porcine, porcine parvovirus (PPV), bovine viral diarrhoea virus (BVDV) and poliovirus were inoculated as $10^5{\sim}10^6$ tissue culture infectious dose $(TCID)_{50}g^{-1}$ into porcine skin. The $D_{10}$ value of E. coli and B. subtilis was measured as $0.32{\pm}0.082kGy$ and $4.0{\pm}0.312kGy$, respectively. Additionally, the $D_{10}$ values of PPV, BVDV and poliovirus were also shown as $1.75{\pm}0.131kGy$, $3.70{\pm}0.212kGy$ and $6.26{\pm}0.332kGy$, respectively. Gamma irradiation decreased the tensile strength of porcine tendon. Results indicate that microbiological safety of porcine tendon can be improved significantly by gamma irradiation. However, further studies are needed to improve the tensile strength of gamma-irradiated porcine tendon.

• Nuclear industry
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• v.26 no.9 s.283
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• pp.70-78
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• 2006

이 보고서는 국제원자력기구(IAEA, International Atomic Energy Agency) 회원국의 요청에 의해 매2년마다 발간되는 “원자력 기술 분석(Nuclear Technology Review)을 요약한 것이며, 2005년 말을 기준으로 발간된 것이다. 원 보고서에 포함된 내용은 원자력 발전, 핵융합, 핵연료, 방사성 동위원소 및 방사선, 관련 연구 개발 등에 대한 오늘과 향후 발전상을 검토한 것이나 여기서는 원자력 발전을 중심으로 요약했다. 보다 궁금한 사항은 IAEA 연례보고서인 2006년 Annual Report에서도 볼 수 있으며 홈페이지인 WWW.iaea.org을 방문하여 영어로 된 보고서를 접할 수 있다. 이 보고서를 요약한 것은 IAEA에서 보는 각국 및 세계 원자력의 현황과 전망을 소개함으로써 국내의 많은 원자력 가족 및 원자력산업에 조금이라도 도움이 되었으면 하는 데 있다.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.231-236
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• 1997

방사성물질의 수송 및 저장용기 등에 사용되는 실리콘고무계 및 수소 첨가된 비스페놀-A형 에폭시수지계 중성자 차폐재들의 인장강도, 압축강도, 비중, 무게, 수소함량 등에 방사선이 미치는 영향을 검토하였다. 방사선 조사선량의 증가에 따라 실리콘고무계 중성자 차폐재(KNS-101 및 102)들의 인장강도, 압축강도, 비중 등이 증가하는 경향을 나타내었으며, 차폐재의 무게는 거의 변화가 없었으나, 수소함량은 약간 감소하는 경향을 나타내었다. 또한 에폭시수지계 중성자 차폐재(KNS-201 및 202)들의 인장강도 및 압축강도는 0.1 MGy까지는 방사선 조사선량의 증가에 따라 증가하다가 0.1MGy 이상에서는 감소하는 경향을 나타내었으며, 조사선량의 증가에 따른 차폐재들의 비중, 무게 및 수소함량은 크게 변하지 않는 것으로 나타났다.

• Journal of Radiation Industry
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• v.4 no.4
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• pp.365-372
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• 2010

Irradiation has been recognized as a highly suitable tool to aid in the formation of hydrogel. The radiation process has various advantage, such as easy process control and the lack of necessity for initiators and crosslinker. In this study, the hydrogel containing the citrus fermentation gel for the wound healing were successfully synthesized. The strength of hydrogel was increased as a function of a increasing the concentration of citrus and the irradiation doses. In addition, this hydrogel have been evaluated by the cytotoxicity and animal experiment.

• Journal of Radiation Protection and Research
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• v.1 no.1
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• pp.31-36
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• 1976

• Nuclear industry
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• v.26 no.6 s.280
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• pp.91-98
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• 2006

방폐장 처분 방식 평가 항복 기준 등 결정/ 한국-인도네시아 원자력협정 가서명/ KEDO 경수로 사업10년 6개월 만에 공식 종료/ 고리1호기 최근 10년 동안 6번 무고장 운전 달성/ 알제리 원자력위원장 방한/ 원전 기관 업체, 해외 공동 진출 적극 협력키로/ 원자력 통제제도 종합 개산 계획 수립 및 추진/ 국제핵융합실헙로(ITER)프로젝트 본격 착수/ 2006 방사선 및 방사성동위원소 이용진흥 연차대회 개최/ 원전 방폐장 정보 교환/ 중성자 유도관 국산화/ 중국 원전사업자단 방문/ 제5기 「원자력대학생 논문연구회」출범/ 윤맹현 한전 원자력연료(주) 신임 사장 취임/ KAIST 조남진 교수/ 서울대 김창효 교수, KAIST 장순흥 교수