• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2006년도 학술논문요약집
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• pp.86-86
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• 2006

• Journal of Plant Biology
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• 제8권1_2호
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• pp.5-10
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• 1965

The effect of radioactive sulfur-35 on the growth and tissue respiration in rye, Secale cereale L., seedlings were studied in this investigation. The growth and respiration rate of the materials treated with the different intensities of radioactivity, represented by the different concentration(${\mu}c$) of radioactive sulfur were shown similar effects in treated groups as those of Gamma-ray or X-ray irradiation on plant materials. However, in the groups of ($0.1{\mu}c$ and ($0.4{\mu}c$ S35-solution, the growth and respiration rate were stimulated somewhat more clearly than in case of control. And the higher concentration groups, $1.6{\mu}c$, $6.4{\mu}c$, and $25.6{\mu}c$ were depressed of the growth and tissue respiration rate. The present data could be explained on the basis that the higher concentration treatments with the radioactive isotope did produce injury to the plant metabolism generally, but the moderate treatment would stimulate to the plant growth and tissue respiration.

• 한국수소및신에너지학회논문집
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• 제26권6호
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• pp.541-546
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• 2015

Global energy shortage problem is expected to increase driven by strong energy demand growth from developing countries. Nuclear fusion power offers the prospect of an almost infinite source of energy for future generations. Hydrogen isotope storage and delivery system is a important subsystem of a nuclear fusion fuel cycle. Metal hydride is a method of the high-density storage of hydrogen isotope. For the safety storage of hydrogen isotope, depleted uranium (DU) has been widely proposed. But DU needs a safe test because It is a radioactive substance. The authors studied a small-scale DU bed and a medium-scale DU bed for the safety test. And then we made a large-scale DU bed and stored hydrogen isotopes in the bed. Before the hydriding/dehydriding, we tested it's heating and cooling properties and carried out an activation procedure. As a result, Reaction rate of DU-$H_2$ is more rapid than the other metal hydride ZrCo. Through the successful storage result of our large bed, the development possibility of the hydrogen isotope storage technology seems promising.

• 자원환경지질
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• 제56권5호
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• pp.547-555
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• 2023

분석 기기의 발달과 더불어 자연 우라늄 동위원소 비(²³⁸U/²³⁵U)와 분별작용에 대한 연구가 점차 증가하고 있다. MC-ICP-MS을 이용한 우라늄 동위원소의 정밀한 분석이 가능해지면서 137.88의 고정된 값으로 여겨졌던 자연 물질의 ²³⁸U/²³⁵U 비가 우라늄 동위원소 분별작용에 의해 최대 수 퍼밀까지 변화할 수 있다는 것이 밝혀졌다. 본 고찰에서는 우라늄 동위원소의 분석과 표기에 대해 간략하게 설명한 후, 지구 상 주요 물질들의 우라늄 동위원소 값(δ²³⁸U)의 변화와 지구화학적 특징을 살펴본다. 특히, 우라늄 광상의 유형과 특징에 따른 우라늄 동위원소 조성 연구 사례를 소개하고, 상대적으로 큰 δ²³⁸U 범위를 야기하는 우라늄 동위원소 분별작용에 대해 논의한다. 이를 바탕으로 고준위 방사성 폐기물 처분장의 모의 실험을 위한 자연 유사 모델로서 우라늄 광상이 갖는 연구 의의에 대해 고찰한다.

• Nuclear Engineering and Technology
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• 제56권1호
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• pp.335-339
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• 2024

Employees of nuclear medicine facilities performing medical procedures with the use of open radioactive sources require continuous detailed control of exposure to ionizing radiation. Thermoluminescent (TL) detectors placed in dosimeters: for the whole body, for lenses, ring and wrist dosimeters were used to assess exposure. The highest whole-body exposure of (1.70 ± 1.09) µSv/GBq was recorded in nurses administering radiopharmaceutical to patients. The highest exposure to lenses and fingers was recorded for employees of the quality control zone and it was (8.08 ± 2.84) µSv/GBq and a maximum of (1261.46 ± 338.93) µSv/GBq, respectively. Workers in the production zone received the highest doses on their hands, i.e. (175.67 ± 13.25) µSv/GBq. The measurements performed showed that the analyzed workers may be classified as exposure category A. Wrist dosimeters are not recommended for use in isotope laboratories due to underestimation of ionizing radiation doses. Appropriately selected shields, which significantly reduce the dose received by employees, must be used in isotope laboratories. Periodic measurements confirmed that the appropriate optimization of exposure reduces the radiation doses received by employees.

• 방사성폐기물학회지
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• 제14권3호
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• pp.279-287
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• 2016

경주 중 저준위 방사성폐기물 처분시설의 운영에 따라, 한국원자력연구원(대전)에 임시보관 중인 방사성동위원소폐기물을 처분시설로 육상운반하였다. 본 연구에서는 방사성동위원소폐기물의 국내육상운반에 따른 작업자 및 일반인에 대한 방사선 피폭선량을 평가하고 그 결과를 국내 방사선피폭 법적제한치와 비교하였다. 또한 방사성폐기물의 상하차 작업 시 작업자와 드럼 간 거리 및 방사성핵종 누출율의 변화에 따른 예상피폭선량의 민감도를 분석하였다. 정상 및 사고조건에서의 예상피폭선량은 국내 법적제한치를 충분히 만족하였음을 확인하였다.

• 방사선산업학회지
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• 제10권1호
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• pp.37-41
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• 2016

The recent prevalence of PET examinations in Korea has led to an increase in the number of cyclotrons. The medical isotope $^{18}F$ produced in most cyclotron facilities currently operating in Korea is emitted into the environment during the production of [$^{18}F$]FDG, a cancerdiagnosis reagent. The amount of [$^{18}F$]FDG synthesized determines the radioactive concentration of $^{18}F$ in the exhaust. At some facilities, this amount temporarily exceeds the emission limit. In this study, we evaluated the $^{18}F$ radioactivity concentration in the exhaust from the cyclotron facility at Chosun University. The $^{18}F$ radioactivity concentration was measured using an air sampler and a HPGe semiconductor detector. The measurements showed that the radioactive concentration of $^{18}F$ in the exhaust at the cyclotron facility at Chosun University was the highest during [$^{18}F$]FDG synthesis but remained under the legal limit of $2,000Bq\;m^{-3}$.

• 자원리싸이클링
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• 제31권5호
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• pp.20-25
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• 2022

본 연구에서는 방사성 폐액내 포함된 방사성 핵종인 세슘-137(Cs-137) 및 스트론튬-90(Sr-90)의 친환경적인 제염을 위해 미세조류의 적용 가능성을 평가하였다. Cs-137 및 Sr-90이 각각 함유된 일원계 표준 방사성 용액과 3차 증류수를 희석하여 1.5 Bq/mL Cs-137, 1.0 Bq/mL Sr-90 농도로 제조한 뒤 실험에 사용하였다. 미세조류는 2종을 사용했으며, Sr-90 제염에는 Chlorella Vulgaris를 사용하였고, Cs-137 제염에는 Hematococcus pluvialis를 사용하여 실험을 수행하였다. 실험 방법은 2주 간 배양된 미세조류를 반투과막이 부착된 병에 투입한 뒤, 미세조류가 투입된 병을 제조된 방사성 용액에 투입하여, 반투과막을 통해 미세조류와 방사성 용액이 48 시간 동안 반응하도록 하였다. 각 시료에 대한 방사능 농도 분석은 γ선 동위원소인 Cs-137은 감마선 핵종 분석기를 사용하였고, β선 동위원소인 Sr-90은 액체섬광계수기(LSC: Liquid Scintillation Count)를 사용하였다. 실험 결과, Cs-137은 약 88.0 %, Sr-90은 약 89.7 % 제염이 가능함을 확인하였으며, Sr-90은 2단 제염 방법에 의해 최종적으로 약 98.6 % 제염이 가능하였다.

• Journal of Radiation Protection and Research
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• 제35권4호
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• pp.167-171
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• 2010

Fixed radiation portal monitors (RPMs) deployed at border, seaport, airport and key traffic checkpoints have played an important role in preventing the illicit trafficking and transport of nuclear and radioactive materials. However, the RPM is usually large and heavy and can't easily be moved to different locations. These reasons motivate us to develop a mobile radiation detection system. The objective of this paper is to report our experience on developing the mobile radiation detection system for search and detection of nuclear and radioactive materials during road transport. Field tests to characterize the developed detection system were performed at various speeds and distances between the radioactive isotope (RI) transporting car and the measurement car. Results of measurements and detection limits of our system are described in this paper. The mobile radiation detection system developed should contribute to defending public's health and safety and the environment against nuclear and radiological terrorism by detecting nuclear or radioactive material hidden illegally in a vehicle.

• Nuclear Engineering and Technology
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• 제55권1호
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• pp.378-390
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• 2023

The SPES (Selective Production of Exotic Species) facility, currently under development at Legnaro National Laboratories of INFN, aims at the production of intense RIB (Radioactive Ion Beams) employing the Isotope Separation On-Line (ISOL) technique for interdisciplinary research. The radioactive isotopes of interest are produced by the interaction of a multi-foil uranium carbide target with a 40 MeV 200 μA proton beam generated by a cyclotron proton driver. The Target Ion Source (TIS) is the core of the SPES project, here the radioactive nuclei, mainly neutron-rich isotopes, are stopped, extracted, ionized, separated, accelerated and delivered to specific experimental areas. Due to efficiency reasons, the TIS unit needs to be replaced periodically during operation. In this highly radioactive environment, the employment of autonomous systems allows the manipulation, transport, and storage of the TIS unit without the need for human intervention. A dedicated remote handling infrastructure is therefore under development to fulfill the functional and safety requirement of the project. This contribution describes the layout of the SPES target area, where all the remote handling systems operate to grant the smooth operation of the facility avoiding personnel exposure to a high dose rate or contamination issues.