• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2003년도 춘계 학술발표회 논문집
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• pp.431-435
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• 2003

Because the Tissue Bound Tritium of food irradiates the organic tissues of a man during a longer time than the Tissue Free Water Tritium, we found the ratio of labile and bound hydrogen, which is the direct source of TBT concentration, in grain such as rice and barley. Tissue free water was extracted from rice and barley sampled, adjacent to Wolsung nuclear power plants of CANDU type, by freeze-drying. Tissue bound water was taken from some of the dried samples by high-pressure combustion. The other of the samples was washed by tritium-free water for 2-3 hours, and dried again by freeze-drying. Tissue bound water was taken again from some of the second dried samples by the combustion. The extracted tissue free and bound waters were distilled and TFWT and TBT concentrations of them were counted by a liquid scintillation counter. Through alternating washing, drying and combustion until the concentration of TBT would be constant, the tritium concentration existing as bound hydrogen was found. The ratios of labile and bound hydrogen of rice and barley were determined by TR concentration, initial TBT concentration and bound tritium concentration. The ratios of bound hydrogen of rice and barley were 0.55, 0.60 relatively.

• Journal of Radiation Protection and Research
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• 제34권2호
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• pp.55-64
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• 2009

In a pressurized heavy water reactor (PHWR), radiation workers who have access to radiation controlled areas submit their urine samples to health physicists periodically; internal radiation exposure is evaluated by the monitoring of these urine samples. Internal radiation exposure at PHWRs accounts for approximately 20 $\sim$ 40% of total radiation exposure; most internal radiation exposure is attributed to tritium. Carbon-14 is not a dominant nuclide in the radiation exposure of workers, but it is one potential nuclide to be necessarily monitored. Carbon-14 is a low energy beta emitter and passes relatively easily into the body of workers by inhalation because its dominant chemical form is radioactive carbon dioxide ($^{14}CO_2$). Most inhaled carbon-14 is rapidly exhaled from the worker's body, but a small amount of carbon-14 remains inside the body and is excreted by urine. In this study, a method for dual analysis of tritium and carbon-14 in urine samples of workers at nuclear power plants is developed and a method for internal dose assessment using its excretion rate result is established. As a result of the developed dual analysis of tritium and carbon-14 in urine samples of radiation workers who entered the high radiation field area at a PHWR, it was found that internal exposure to carbon-14 is unlikely to occur. In addition, through the urine counting results of radiation workers who participated in the open process of steam generators, it was found that the likelihood of internal exposure to either tritium or carbon-14 is extremely low at pressurized water reactors (PWRs).

• Journal of Radiation Protection and Research
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• 제8권2호
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• pp.8-14
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• 1983

삼중수소의 단일 피폭과 만성피폭에 의한 한국인의 내부피복 선량을 삼단계형모델을 이용하여 계산하였다. 이 모델은 체내수분과 조직체 사이의 삼중 수소의 축적량을 잘 나타내 주는 것이다. 그 결과 삼단계형의 축적 반감기 9, 30과 450일을 사용한 단일 피폭의 총 선량은 1mCi/kg 섭취당 17.64mrad였고 이것의 97%는 체내수분에 있는 삼중수소에 의한 선량이고 나머지 3%는 조직내 삼중수소에 의한 것이다. 그리고 1 mCi/day의 삼중 수소를 섭취하는 만성 피폭의 경우, 총 선량은 85.5mrad/day이었다. 또한 본 연구에서는 한국인에 대한 최대허용 농도값을 선질계수 1을 사용하여 계산하였다. 그 결과, ICRP의 최대허용 농도값은 약 50%가량 낮게 평가되었으므로 한국인의 최대허용 농도값은 ICRP의 결과보다 약 50%높게 책정되어야만 한다.

• Nuclear Engineering and Technology
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• 제53권6호
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• pp.1991-1999
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• 2021

The response changes of the specific growth rate of Lemna minor duckweed was modeled using the logarithms of frond numbers on tritium activity concentration and gamma radiation dose from cobalt 60. The concept of average specific growth rate depends on the general exponential growth pattern, where toxicity is estimated based on the effect on the growth rate. One of the main questions of the effect of the radiation dose on duckweed is how to correlate the effect of beta radiation with the effect of any other radiation for modeling radiation on Lemna minor. Experimental data were extrapolated by utilizing the OECD guidelines. A linear relationship of absorbed dose and activity concentration was obtained for the average dependency growth rate of Lemna minor as D = (0.1257)·A^0.585. The dose rate of gamma irradiation from ⁶⁰Co increases with tritium activity dependence, on the specific growth rate of the Lemna minor duckweed. An increase in the tritium activity causes a decrease in the specific growth rate of the Lemna minor duckweed. It indicates that as the quantity of the beta radiation dose increase in Lemna minor duckweed, a higher quantity of gamma radiation will be required to cause the same effect in the specific growth rate of Lemna minor duckweed. The relation between the inhibition of the Lemna minor seedling growth and gamma and beta radiation dosage agrees roughly with that between the decrease of survival rate or fertility and dosage.

• 한국수소및신에너지학회논문집
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• 제23권1호
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• pp.49-55
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• 2012

Hydrogen isotopes accountancy and storage are important functions in a nuclear fusion fuel cycle. The hydrogen isotopes are safely stored in metal hydride beds. The tritium inventory of the bed is determined from the decay heat of tritium. The decay heat is measured by circulating helium through the metal hydride bed and measuring the resultant temperature increase of the helium flow. We are reporting our preliminary experimental results on the hydrogen isotopes accountancy and storage performance in a metal hydride bed.

• Journal of Radiation Protection and Research
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• 제28권4호
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• pp.337-342
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• 2003

On a basis of the washout model and concentrations of anthropogenic tritium in rainwater around the Wolsong site, the washout coefficients of tritium by rainwater were calculated, and the validity of washout deposition model are estimated. As the result of that, the washout coefficients in 10 sampling stations around Wolsong site were in the range of $2.9{\times}10^{-5}\;-\;16{\times}10^{-5}\;s^{-1}$ with the mean value of $7.21{\times}10^{-5}\;s^{-1}$. The validity of the washout deposition model was confirmed by comparing the observed data with the calculated ones.

• Journal of Korean Society for Atmospheric Environment
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• 제10권E호
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• pp.299-302
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• 1994

At a nuclear power plant, environmental radioactivity monitoring is routine work for the radiation safety management For the environmental monitoring of tritium($^3$H) activity in water sampled liquid scintillation counting( LSC) method is applied to measure low- energy beta activity from tritium in the samples. The $^3$H activity is measured using the BECKMAN 5801 system at the KRISS( Korea Research Institute of Standards and Science) for evaluating the lower limits of detection( LLD) of $^3$H measurement and the measuring capability of low-level $^3$H activity at four nuclear Power Plant sites. The LSC systems used for low-level $^3$H activity measurements at the nuclear Power Plants are confirmed to satisfy throughout an intercomparison study under the experimental arrangements by the KRISS.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2564-2569
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• 2021

The neutronic analysis of Helium Cooled Ceramic Reflector (HCCR) breeding blankets has been performed using the 3D Monte Carlo code MCNPX and ENDF nuclear data library. This study aims to reduce ⁶Li percentage in the breeder zones as much as possible ensuring tritium self-sufficiency. This work is devoted to investigating the effect of ⁶Li percentage on the HCCR breeding blanket's neutronic parameters, such as neutron flux and spectrum, Tritium Breeding Ratio (TBR), nuclear power density, and energy multiplication factor. In the ceramic breeders at the saturated thickness, increasing the enrichment of ⁶Li reduces its share in the tritium production. Therefore, ceramic breeders typically use lower enriched Li from 30% to 60%. The investigation of neutronic analysis in the suggested geometry shows that using 60% ⁶Li in Li₂TiO₃ can yield acceptable TBR and energy deposition results, which would be economically feasible.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.247-247
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• 2004

가압 중수로형 원자력발전소에서는 원자로의 감속재 및 냉각재로 사용하는 중수(heavy water)로 인한 삼중수소(tritium)의 생성이 전체 방사선 준위 상승의 가장 중요한 원인이 되고 있다. 따라서 4기의 중수로가 운전 중인 우리나라에서도 월성원자력 발전소에 삼중수소 제거 설비(Tritium Removal Facility)가 건설 중에 있다. 이 시설로부터 99% 이상의 순도인 삼중수소가 회수되며, 회수된 삼중수소는 장기적인 저장을 위하여 안전하게 포장되어야 한다.(중략)

• Journal of Radiation Protection and Research
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• 제26권3호
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• pp.139-142
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• 2001

The one of important parameter involved in the calculation of internal radiation dose to the human body is the biological half-life of the radionuclide. The biological half-life is population specific and may differ from one population group to another. So the effective half-life of tritium exposure based on urinal bioassay measurement of Wolsong Nuclear Power Plants was investigated and studied.