• Nuclear Engineering and Technology
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• v.53 no.8
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• pp.2570-2575
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• 2021

The exchange behaviors of hydrogen isotopes between protonated lithium metal compounds and deuterated water or tritiated water were investigated. The various protonated lithium metal compounds were prepared by acid treatment of lithium metal compounds with different crystal structures and metal compositions. The protonated lithium metal compounds could more effectively reduce the deuterium concentration in water compared with the corresponding pristine lithium metal compounds. The H⁺ in the protonated lithium metal compounds was speculated to be more readily exchangeable with hydrons in the aqueous solution compared with Li⁺ in the pristine lithium metal compounds, and the exchanged heavier isotopes were speculated to be more stably retained in the crystal structure compared with the light protons. When the tritiated water (157.7 kBq/kg) was reacted with the protonated lithium metal compounds, the protonated lithium manganese nickel cobalt oxide was found to adsorb and retain twice as much tritium (163.9 Bq/g) as the protonated lithium manganese oxide (69.9 Bq/g) and the protonated lithium cobalt oxide (75.1 Bq/g) in the equilibrium state.

• Archives of Pharmacal Research
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• v.20 no.6
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• pp.637-642
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• 1997

Degradation of a compound with a hydroxyl group during the course of its diffusion across the skin was investigated. Based on the experimental findings of ashortened retention time of a degradant peak from post-diffusion samples and from the ability to evaporate radioactivity from such samples, it seems that during diffusion the parent compound degrades into a more hydrophilic product which is then oxidized. A tritium label at the carbon with a hydroxyl group was released as a tritiated water. When the post-diffusion samples were left open to the air allowing evaporation of water, there was a corresponding decrease in radioactivity of such samples. There was a linear relationship between the time left open and the fraction of radioactivity lost. When such samples were fractionated by HPLC, and then had their radioactivities measured by scintillation counting, two peaks wre identified. The first peak, which may be attributable to tritiated water, was eluted at the same retention time as the solvent front. The second peak eluted at the retention time of the parent compound. When the evaporation/loss of radioactivity experiment was repeated using a $^{14}C$-labeled compound there was no significant loss of radioactivity, indicating that the earlier loss with $^{3}H$-labeled compound was related to the formation and loas sof tritiated water.

• Journal of Radiation Protection and Research
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• v.22 no.2
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• pp.97-101
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• 1997

During the period of March 1995 to December 1995, tritium concentrations of tritiated water vapor (HTO) and tritiated hydrogen (HT) in the atmosphere in Taejon were measured to evaluate present background levels of tritium in the atmosphere. Air samples were collected continuously for three weeks with a sampling system for tritium in the atmosphere and were analyzed by a liquid scintillation counting system. The range of the atmospheric HTO concentrations was 3.2-36 mBq $m^{-3}$ with a mean value of 16.2 mBq $m^{-3}$. The atmospheric HTO concentrations were the highest in summer and the lowest in winter. This trend was similar to the variation of atmospheric absolute humidity. The specific activities of tritium in atmospheric water vapor in Taejon ranged from 0.62 Bq $L^{-1}$ to 3.82 Bq $L^{-1}$ with a mean value of 2.04 Bq $L^{-1}$. The atmospheric HT concentrations were in the range of 35.7 mBq $m^{-3}$ to 48.9 mBq $m^{-3}$ with a mean value of 41.1 mBq $m^{-3}$.

• Nuclear Engineering and Technology
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• v.35 no.2
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• pp.171-177
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• 2003

A dynamic compartment model was required for the prediction of radiological consequences of the tritiated vapor released from the nuclear facility after an accident. A computer code, ECOREA-T, was developed by incorporating the unit models for the evaluation of tritium behavior in the environment. Dry deposition of tritiated vapor from the atmosphere to the soil was calculated using a deposition velocity. Transport of tritium from the atmosphere to the plant was calculated using a specific activity model, and the result was compared with the Belot's analytic solution. Root uptake of tritiated water from the soil and formation of OBT from T were considered in the model. The ECOREA-T code was verified by comparing the results from the other computer codes using a scenario developed through BIOMOVS II study. The results showed good agreements.

• Journal of Radiation Protection and Research
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• v.46 no.1
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• pp.32-34
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• 2021

• Nuclear Engineering and Technology
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• v.53 no.11
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• pp.3798-3807
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• 2021

Tritium extraction from radioactively contaminated cement mortar samples was performed using heating and liquid scintillation counting methods. Tritiated water molecules (HTO) can be present in contaminated water along with water molecules (H₂O). Water is one of the primary constituents of cement mortar dough. Therefore, if tritium is present in cement mortar, the buildings and structures using this cement mortar would be contaminated by tritium. The radioactivity level of the materials in the environment exposed to tritium contamination should be determined for their disposal in accordance with the criteria of low-level radioactive waste disposal facility. For our experiments, the cement mortar samples were heated at different temperature conditions using a high-temperature combustion furnace, and the extracted tritium was collected into a 0.1 M nitric acid solution, which was then mixed with a liquid scintillator to be analyzed in a liquid scintillation counter (LSC). The tritium extraction rate from the cement mortar sample was calculated to be 90.91% and 98.54% corresponding to 9 h of heating at temperatures of 200 ℃ and 400 ℃, respectively. The tritium extraction rate was close to 100% at 400 ℃, although the bulk of cement mortar sample was contaminated by tritium.

• YAKHAK HOEJI
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• v.32 no.3
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• pp.194-197
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• 1988

We measured the rate of water transfer across the isolated small intestine of the rat in Wiseman apparatus using tritiated water ($^3H_2O$) in drinking beverages such as electrolytes solution, fruit juice, carbonated water and barley water. Initial transfer rate of water using four beverages were determined: Electrolytes solution is the fastest and followed by barley water, carbonated water and fruit juice.

• 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.8 no.2
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• pp.8-14
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• 1983

The doses to Korean adult by a single and chronic intake of tritiated water are determined using a three compartment model, which describes the retention of tritium radionuclide in body water and in bound organic form in the body. The results show that the total dose of a single intake, using retention half-time for the three-compartment of 9, 30, and 450 days, is 17.64 mrads ($176.4{\mu}Gy$) per 1mCi/kg ($3.7{\times}10^7Bq/kg$) intake, 97% of which is due to tritium in body water and 3% to bound tritium in tissue. In the chronic intake of 1mCi/day($3.7{\times}10^7Bq/day$) tritiated water, the total dose is 85.5 mrad/day(0.855mGy/day). Furthermore, in this study (MPC) a and (MPC)w values of tritium for Korean man are calculated by using the modified formula originated from ICRP Publication-2. From the results, we found that the (MPC) a, w values of ICRP underestimated approximately 50%, the (MPC)a, w values of Korean man must be elevated as high as approximately 50% than that of ICRP.

• Journal of Pharmaceutical Investigation
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• v.25 no.3
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• pp.223-226
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• 1995

A new method to study water uptake into biodegradable polymer was developed. Polymer was gently mixed with the tritiated buffer and the radioactivity level of the polymer due to water uptake was measured by liquid scintillation counting. The rate of water uptake was estimated from the plot of the amount of water in the device as a function of time. The technique used in this study is particularly useful for estimating water uptake of biodegradable polymers which were difficult to study by other techniques such as weight gain used for hydrogel.