• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.633-638
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• 1998

벼의 성장시기에 다른 대기중 삼중수소의 식물채내 흡수실험을 수행하였다. 투명한 아크릴로 만들어진 피폭상자(50x60x120cm)내의 피폭조건은 비록 같은양(18.5 MBq)의 HTO를 증발시키더라도 동일한 농도를 유지하는 것이 거의 불가능하였다. 벼꽃의 매화 직후부터 수확기까지 이삭의 생성시기별로 HTO에 피폭시킨 후 잎, 줄기 및 이삭으로 구분된 시료에서 피폭 후 시간별로 조직자유수의 삼중수소 농토를 측정하였다. 조직자유수의 삼중수소 농도는 이삭에서 가장 느리게 감소하였으나 조직결합수의 삼중수소 농도는 이삭 성장이 가장 왕성한 시기에 높게 측정되었다.

• Journal of Radiation Protection and Research
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• v.23 no.1
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• pp.25-32
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• 1998

Tritium is released into the environment as various form but HTO is most relevant to the incorporation of tritium into living organisms and to the formation of OBT. Tritiated compounds may be transported to humans via several tropic levels. Retention times of organically bound tritium in organisms are considerably longer than those of tritiated water, which has significant consequences on exposure dose estimation. It is rather difficult to predict the amount of OBT produced by the photosynthetic process of plants because it may be influenced by a multitude of environmental factors and plant parameters. Tritiated organic matters are classified as the exchangeable or nonexchangeable bound tritium according to the bound form. After short term HTO exposure in plants, the formation and uptake of OBT were evaluated.

• Journal of Radiation Protection and Research
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• v.28 no.1
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• pp.75-78
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• 2003

The organically bound tritium(OBT) concentrations of the marine organisms(seaweed and shellfish) around Wolsung nuclear power plants were measured. The OBT concentrations of seaweeds were in the range of $0.372{\sim}2.72$ Bq/kg-fresh. The OBT concentrations of shellfish were in the range of $0.239{\sim}2.02$ Bq/kg-fresh. The internal dose due to the OBT concentration of seaweed was estimated as $3.4{\times}10^{-7}$ mSv/year.

• Journal of Radiation Protection and Research
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• v.17 no.2
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• pp.25-35
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• 1992

To evaluate tritium level in some environmental samples, tissue-free water tritium (TFWT) and tissue-bound tritium (TBT) were analyzed in rices, chinese cabbages and pine needles collected at 12 locations in Korea. The TFWT was recovered by freeze-drying of the samples and the TBT was obtained in the form of water by combustion of the dried samples. Tritium was measured by liquid scintillation counter. The concentrations of TFWT were in the range of $0.96{\sim}3.96 Bq/1,\; 0.83{\sim}3.40 Bq/1\;and\;1.02{\sim}3.01 Bq/1$ in rices, chinese cabbages and pine needles, respectively. The mean specific activity ratios (TBT/TFWT) were 0.94, 1.71 and 1.39 in rices, chinese cabbages and pine needles, respectiviely. This excess TBT in the samples may be attributed to the fact that the residence time of TBT in the plant is longer than that of TFWT. The specific activity ratio depends on the plant species, the exposed time to tritiated atmosphere, atmospheric moisture, temperature and diffusion factor.

• Journal of Radiation Protection and Research
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• v.23 no.2
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• pp.75-82
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• 1998

Tritium concentration in the atmosphere during HTO exposure was different between two experiments due to different velocity of HTO evaporation. Assimilation rate of the rice plant was considered to be higher than that of Chinese cabbage The uptake of atmospheric HTO into tissue free water tritium(TFWT) was higher in rice plants than in Chinese cabbage. However, organically bound tritium(OBT) concentration is relatively higher in Chinese cabbage than in rice. The specific activity ratio(SAR) increased slowly after HTO exposure and decreased gradually with time. The behaviour of HTO in the soil was affected by the environmental conditions.