• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.144-145
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• 2009

• Nuclear Engineering and Technology
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• v.26 no.4
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• pp.461-470
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• 1994

Sorption experiments of $^{60}$ Co, $^{85}$ Sr. and $^{137}$ Cs onto sandstone particles in a batch were carried out to investigate the migration mobility. Sorption kinetics and reversibility as well as sorption mechanisms were examined. Sorption reaction occurred mostly within 10 hours on the outer surface of the sandstone particle but diffusion into the inner surface of the mineral has still occurred after that time. In order to distinguish sorption types of radionuclides, a sequential chemical extraction was introduced. The sorbed radionuclides were then extracted by applying different solutions of synthetic groundwater, CaCl$_2$, KCl and KOX-HA Especially KCl is adopted to extract the ion-exchanged cesium. Sorption types considered are reversible sorption under groundwater condition, ion exchange, association with ferro-manganese oxides or oxyhydroxides, and irreversible fixation. Strontium sorbs onto the sandstone surface mainly by fast and reversible ion exchange reaction. However, cobalt and cesium do not sorb by simple process. The main sorptive binding of cobalt was the association with ferro-manganese oxides and the secondary one was irreversible fixation. Diffusion into the lattice of minerals controlled the sorption rate of cobalt The main sorptin type of cesium was irreversible fixation, while ion exchange reaction was the secondary importance. Hence the oreder of migration mobility for the three radionuclides was Sr$^{2＋}$ ＞ Co$^{2＋}$ ＞ Cs$^{＋}$ in the sandstones.

• Journal of Ginseng Research
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• v.15 no.3
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• pp.183-187
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• 1991

Effect of ginseng hairy and native roots on body absorption, fecal and urinary excretion of Ingested radiostrontium were investigated in the mouse(NIH-strain, male) treated with or without pre-feeding of each ginseng soluble fraction. The test groups were fed with basic diet supplemented with 1% each ginseng soluble fraction for 7 darts before the radiostrontium were administered by intragastric intubation. In the groups of treated with soluble fraction from ginseng hairy roots, the radioactivities of fecal and urinary excretion increased about 15% over than that of control groups and the whole body retention were about 38%. In the groups of treated with soluble fraction from native ginseng roots, the radioactivities of fecal and urinary excretion increased about 25% over than that of control groups and the whole body retention were about 28%. Also, the levels of radiostrontium accumulation retained significantly the higher percent in skeletons than in other organs.

• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.123-129
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• 1993

Chitosan is known to be one of the natural chelating agents. It is derived from chitin which is a cellulose-like biopolymer distributed widely in nature, especially in shellfish, insects, fungi, and yeast. There are two forms of chitosans, water soluble and insoluble, The purpose of the present study is to investigate whether water soluble chitosan can be applied to reduce the bioabailability of radios-trontium in foods. We compared the effect of water soluble and insoluble chitosans on the absorption of ingested radiostrontium ($^{85}Sr$). Three percent water soluble and insoluble chitosan solutions were given orally, and immediately after $^{85}SrCl_2$ ($0.2{\mu}Ci$) was administered to rats using a orogastric tube. In one group water soluble chitosan solution was given for additional 4 days. And in control group no chitosan was given. Each group consisted of 6 rats. The whole-body retention of $^{85}Sr$, determined by in vivo counting method, was lower in water soluble chitosan group than that of water insoluble chitosan group and that of control. Urinary excretion of $^{85}Sr$ in chitosan-treated rats was higher than that of control. And 5 day ingested group of water soluble chitosan showed least whole body retention of $^{85}Sr$. In conclusion water soluble chitosan was more effective in reducing bioavailability of ingested radiostrontium in the gastrointestinal tract than insoluble chitosan.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.2
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• pp.164-175
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• 2022

In this work, sulfonated poly (ether ether ketone) (SPEEK) composite membranes including strontium zirconate (SrZrO₃) were fabricated by the electrospinning method. Fourier-transform infrared spectroscopic analysis and X-ray diffraction analysis were used to identify the chemical structure and the crystallinity of SrZrO₃ and electrospun composite membranes. The thermal stability of the pure SPEEK and SPEEK/SrZrO₃ electrospun composite membranes were investigated by using thermogravimetric analysis. The physicochemical properties and proton conductivity were enhanced with the addition of different weight ratio of SrZrO₃ nanofiller (2, 4 and 6 wt%) in SPEEK polymer. The optimized SPEEK/SrZrO₃-4 electrospun membrane containing 4 wt% of SrZrO₃ showed a high proton conductivity compared to other electrospun SPEEK/SrZrO₃ composite membranes. The results indicate that electrospun composite membranes incorporating these perovskite nanofillers should be explored as potential candidates for use in proton exchange membrane fuel cells.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.5 no.1
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• pp.79-84
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• 2007

Inventories of soluble elements in the gap and grain boundaries of domestic used PWR fuel pellets were measured to estimate the quantities of radionuclides that are liable to be rapidly released into the groundwater of a disposal site. The gap inventory of cesium for the pellets in the used fuel with a burn-up range of 45 to 66 GWD/MTU showed 0.85 to 1.7% of its total inventory, which was close to 1/6 to 1/3 of the fission gas release fraction (FGRF). However, the amounts of cesium released from the gaps of the pellets below 40 GWD/MTU of a burn-up and less than 1% FGRF were so erratic that the gap inventory could not be defined by ie FGRF. Strontium inventories in the gap and grain boundaries of the pellets in the same rod were not significantly varied, and the iodine inventory in the gap of the used PWR fuels was estimated to be less than or the same as the FGRF.

• Nuclear Engineering and Technology
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• v.22 no.4
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• pp.315-325
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• 1990

The analytical repository source term (REPS) computer code is developed for the safety assessment of radioactive waste geologic repository. For reliable prediction of the leach rates for various radionuclides, degradation of concrete structures, corrosion rate of waste container, degree of corrosion on the container surface, and the characteristics of radionuclides are considered in this REPS code. For the validation of the radionuclide leach rates predicted by the REPS model, the calculated leach rates of Cs-137, Sr-85, and Co-60 are compared with two reported leaching test results. Cesium and strontium leach congruently, and the leaching test results of these species can be reproduced by the congruent leaching model included in the REPS model. In case of cobalt, the solid diffusion model is in good agreement with the leaching test results.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.61-69
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• 2014

Carboxymethyl-${\beta}$-cyclodextrin (${\beta}$-CMCD), as a biodegradable surfactant with hydrophobic and hydrophilic properties, has potential advantages of being applicable to the simultaneous treatment of multiple contaminated soils. In this study, the desorption behaviors of r adionuclides such as cobalt (Co), strontium (Sr), and cesium (Cs) from the soil contaminated with them were experimentally investigated and the effectiveness of CMCD as a desorbent was evaluated. The desorption equilibrium of used radionuclides could be achieved within 1~3 hr and the desorption ratio from kaolin was higher than that from natural soil. The addition of CMCD of 2 g/L increased the desorption ratio by 5~20 % and the desorption ratio of used r adionuclides was shown in the order of Co > Cs > Sr. The experimental desorption data were fitted successfully by pseudo-second order kinetic model and the desorption rate of the r adionuclides was shown in the order of Cs > Co > Sr. Hysteresis between adsorption and desorption of the r adionuclides, as shown in the order of Sr > Co > Cs, increased as the desorption rate decreased. Consequently, it could be considered that the desorption rate was one of the significant factors of the hysteresis. The addition of CMCD as desorbent increased the amount of desorbed radionuclides and decreased the hysteresis. However, the CMCD could not completely desorb the radionuclides from soils even though the excess of CMCD was added.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.2
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• pp.73-78
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• 2009

The decay heat of Cs and Sr contained in a LiCl waste salt, generated from an electrolytic reduction process in pyroprocessing of spent nuclear fuel, has been calculated. The calculation has been carried out under some assumptions that most of the LiCl waste is purified and recycled to main process, and the residual is fabricated to make a waste form. As a result, the decay heat from daughter nuclides such as Ba and Y seems to be maximum 4.6 times higher than that from their parent nuclides such as Cs and Sr. The thermal release from Cs and Sr in the LiCl waste is the maximum around the first one month, so an cooling system operation for some time at the beginning would be suggested to control a rapid increase in the temperature of the LiCl waste salt.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.1
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• pp.83-89
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• 2014

The aim of this study is to investigate the sorption/ion exchange of radioactive nuclides such as $Cs^+$ and $Sr^{2+}$ by synthetic Na-micas. In order to prepare Na-micas, two natural micas (phlogopite and biotite) were used as precursor materials. XRD, SEM, and EDS analyses were used to examine material characterization of synthetic Na-micas. Analyses of materials revealed that Na-micas were successfully obtained from natrual micas by K removal treatment. On the other hand, single solute (Cs or Sr) and bi-solute (Cs/Sr) sorption experiments were carried out to determine sorption capacity of Na-micas for Cs and Sr under different pH and ionic strength conditions. Uptake of Cs and Sr by micas in bi-solute system was lower than in single-solute system. Additionally, Langmuir and Langmuir competitive models were applied to describe sorption isotherm of Na-micas. bi-solute system was well described by Langmuir competitive models. For the results obtained in this study, Na-micas could be promising sorbents to treat multi-radioactive species from water and groundwater.