• 한국환경농학회지
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• 제2권1호
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• pp.30-34
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• 1983

원자력시설(原子力施設)에서 방출(放出)될 수 있는 주요 핵종중(核種中)에서 $Cs^{137}$을 인위적으로 토양(土壤)에 처리(處理)하여 작물체(作物體)에 흡수(吸收), 이행(移行) 및 농축관계(濃縮關係)를 구명(究明)하고자 pot(토양(土壤)10㎏)당(當) $0.5{\sim}60{\mu}Ci$로 처리(處理)한 후 대두(大豆)를 재배(栽培)하여 다음과 같은 결과(結果)를 얻었다. 1) 공시(供試)된 $Cs^{137}$의 상기(上記) 처리농도(處理濃度)에서는 대두작물(大豆作物)의 생장저해(生長沮害) 영향을 볼 수 없었다. 2) 처리농도(處理濃度) 증가(增加)에 따라 대두작물(大豆作物)의 $Cs^{137}$흡수(吸收)는 증가(增加)하였으나 K함양(含量)은 감소(減少)하였으므로 두 이온간(間)의 길항성(拮抗性)을 보였다. 3) 생육시기별(生育時期別) 흡수량(吸收量)은 pod 형성기(形成期)까지는 증가(增加)하다 수확기(收穫期)에는 감소(減少)하는 경향을 보였고 종실(種實)에 비해 경엽부(莖葉部)에 높은 축적(蓄積)을 보였다. 4) 대두작물(大豆作物)의 $Cs^{137}$ 흡수률(吸收率)은 $0.069{\sim}0.005$의 범위로 $Cs^{137}$처리농도(處理濃度)에 따라서 감소(減少)하였고, 이행률(移行率)은 평균(平均) 38.6%였고, 종실(種實)에의 농축계수(濃縮係數) 또한 농도(濃度)의 증가(增加)에 따라 감소(減少)하였으며 $20{\mu}Ci$처리구(處理區)를 기준(基準)으로 할 경우 농축계수는 0.04 였다.

• 한국해양학회지
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• 제10권2호
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• pp.51-56
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• 1975

Continued to the previous papers, the present investigation is carried out to clarify cesium-137 activities and potassium contents among 54 samples of edible marine algae collected along the coast of Korea during September, 1973 and April, 1974. The potassium contents are variable, 1.5-29.6%, and 11.36% on an average, while most of the members contain them about 10-16% generally. Among the algal phyla, they are 13.49% in green, 10.82% in brown and 16.46% in red algae, respectively. Cesium-137 activities are variable, 0.19-8.13 pCi$\^$137/ Cs/g K, and 2.35 pCi$\^$137/Cs/g K on an average in the samples investigated. Among the algal phyla they are 4.35 in green, 2.17 in brown and 0.89 pCi $\^$137/Cs/g K in red algae, respectively. Green algae contain especially higher activities compared with the other two groups. The brown alga, Myelophycus caespitosus shows the highest activities, 8.13 pCi$\^$137/Cs/g K, among the members investigated. Considering the concentration factor, this plant would be an indicator plant of cesium-137 among the marine algae along the coast of Korea.

• Journal of Radiation Protection and Research
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• 제3권1호
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• pp.1-5
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• 1978

Cs-137과 같은 반감기가 긴 방사성 핵종을 함유한 저준위 방사성 액체 폐기물을 국산 제올라이트 일종인 Clinoptillolite를 이용해서 처리할 수 있는가를 연구했다. Column 장치를 사용하여 Break-Through Curve를 얻어서 미국의 광물전문회사인 WARD에서 분류한 천연 Clinoptillolite 원광과 비교한 결과, 국산 Clinoptillolite에는 Break-Through Curve의 모양에 'Tailing'이 일어나는 것을 나타냈다. 국산 Clinoptillolite에 500ppm의 Cesium 용액에 $2.5{\times}10^{-3}{\mu}Ci/ml$의 Cs-137을 넣어서 Cesium 이온고정능력을 실험한 결과 132meq/100g이 고정되었다. 또한 Tracer로 넣은 Cs-137이 $75{\mu}Ci/100g$이 고정됨을 보여주었다.

• Nuclear Engineering and Technology
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• 제55권2호
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• pp.516-522
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• 2023

The co-precipitation process plays a key role in the decontamination of radionuclides from low and intermediate levels of liquid waste. For that reason, the removal of Cs ions from waste solution by the co-precipitation method was carried out. A simulated liquid waste (¹³³Cs) was prepared from a 0.1 M CsCl solution, while wastewater generated by washing steel ash served as a representative of radioactive cesium solution (¹³⁷Cs). By co-precipitation, potassium ferrocyanide was applied for the adsorption of Cs ions, while nickel nitrate and iron sulfate were selected for supporting the precipitation. The amount of residual Cs ions in the CsCl solution after precipitation and filtration was determined by ICP-OES, while the radioactivity of ¹³⁷Cs was measured using a gamma-ray spectrometer. After cesium removal, the amount of cesium appearing in both XRD and SEM-EDS was analyzed. The removal efficiency of ¹³³Cs was 60.21% and 51.86% for nickel nitrate and iron sulfate, respectively. For the ash-washing solution, the removal efficiency of ¹³⁷Cs was revealed to be more than 99.91% by both chemical agents. This implied that the co-precipitation process is an excellent strategy for the effective removal of radioactive cesium in waste solution treatment.

• 상하수도학회지
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• 제28권5호
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• pp.549-554
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• 2014

This study was evaluated the applicability of the membrane filtration process (Micro Filtration (MF), nanofiltration membranes (NF), reverse osmosis (RO)) on the major radioactive substances, iodine ($I^-$) and cesium ($Cs^+$) using membranes produced in Korea and domestic raw water. Iodine ($I^-$) or cesium ($Cs^+$) in the microfiltration membrane (MF) process could not be expected removal efficiency by eliminating marginally at the combined state with colloidal and turbidity material. At the domestic raw water (lake water, turbidity 1.2 NTU, DOC 1.3 mg/L) conditions, nanofiltration membrane (NF) and reverse osmosis (RO) showed a high removal rate of about 88 ~ 99% for iodine ($I^-$) and cesium ($Cs^+$) and likely to be an alternative process for the removal of radioactive material.

• 방사성폐기물학회지
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• 제19권1호
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• pp.39-49
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• 2021

The behaviors of various desorption agents were investigated during the desorption of cesium (Cs) from samples of clay minerals and actual soil. Results showed that polymeric cation exchange agents (polyethyleneimine (PEI)) efficiently desorbed Cs from expandable montmorillonite, whereas acidic desorption solutions containing HCl or PEI removed considerable Cs from hydrobiotite. However, most desorption agents could desorb only 54% of Cs from illite because of Cs's specific adsorption to selective adsorption sites. Cs desorption from an actual soil sample containing Cs-selective clay mineral illite (< 200 ㎛) and extracted from near South Korea's Kori Nuclear Power Plant was also investigated. Considerable adsorbed 137Cs was expected to be located at Cs-selective sites when the 137Cs loading was much lower than the sample's cation exchange capacity. At this low 137Cs loading, the total Cs amount desorbed by repeated washing varied by desorption agent in the order HCl > PEI > NH4+, and the highest Cs desorption amount achieved using HCl was 83%. Unlike other desorption agents with only cation exchange capabilities, HCl can attack minerals and induce dissolution of metallic elements. HCl's ability to both alter minerals and induce H+/Cs+ ion exchange is expected to promote Cs desorption from actual soil samples.

• 대한화학회지
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• 제5권1호
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• pp.29-32
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• 1961

Two methods for the determination of Cesium-137 in various foods(ashes) were compared. The one comprises two steps, the first being the separation of alkalies as cobaltinitrites or perchlorates by the radiochemical method, and the second being the measurement of photopeak area due to the presence of Cs-137 by the use of scintillation spectrometer. The other method is the direct subjection of ash samples to the spectrometry without the radiochemical separation. The combined contribution of K-40 and Rb-87 to the spectrum was not found on account of the difference in energies of these nuclides. These two methods gave, a good agreement in the determination of Cs-137 in 50-100g ash samples of vegetables or cereals under investigation.

• Journal of Radiation Protection and Research
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• 제45권4호
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• pp.154-162
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• 2020

Background: Several studies have reported that wild mushrooms contain high amounts of radioactive cesium (137Cs). After the Fukushima Daiichi Nuclear Power Plant Accident, a significantly high concentration of 137Cs has been detected in wild mushrooms, and their consumption may be the cause of the chronic internal exposure of local consumers to radioactivity. Therefore, an accurate evaluation of the internal radioactivity resulting from mushroom ingestion is needed. Materials and Methods: The 137Cs elution rate through the cooking and digestion stages was evaluated using in vitro experiments. The edible mushroom Pleurotus djamor was taken as a sample for the experiments. The mushrooms were cultivated onto solid media containing 137Cs. We evaluated the internal dose based on the actual conditions using the elution rate data. For various cooking methods, the results were compared with those of other wild edible mushrooms. Results and Discussion: From the elution experiment through cooking, we proved that 25%-55% of the 137Cs in the mushrooms was released during soaking, boiling, or frying. The results of a simulated digestion experiment after cooking revealed that almost all the 137Cs in the ingested mushrooms eluted in the digestive juice, regardless of the cooking method. The committed effective dose was reduced by 20%-75% when considering the dissolution through the cooking process. Conclusion: We found that cooking lowers 137Cs concentration in mushrooms, therefore reducing the amount of radioactivity intake. Besides, since there were differences between mushroom types, we demonstrated that the internal exposure dose should be evaluated in detail considering the release of 137Cs during the cooking stages.

• 공업화학
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• 제29권2호
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• pp.127-137
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• 2018

후쿠시마 다이치 핵발전소의 사고 이후 방사능 오염이 중요한 환경 관심사가 되었다. 원자량 134와 137 세슘은 주요 핵분열 산물이며, 이물질들은 방사능 오염의 주된 문제들이다. 후쿠시마 다이치 핵 발전소 사고에서 다량의 세슘이 방출되었으며, 이 사고의 결과, 많은 연구자들이 방사능-독성 세슘 제거를 위한 흡착제 개발에 집중하였다. 본 총설에서는 세슘 제거를 위하여 각광을 받는 물질로서 청색 안료와 이와 유사한 화합물 제조의 최근 발전 동향을 자세하게 검토하였다. 또한, 다양한 형태의 점토와 점토 기반 흡착제 및 새로 개발된 흡착제를 이용한 세슘 흡착의 최근 연구들을 고찰하였다.

• Nuclear Engineering and Technology
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• 제36권4호
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• pp.304-315
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• 2004

The ageing effects of radionuclides in radioactive soil on remediation using the electrokinetic method were analyzed. Comparative experiments were conducted for the reactive soil around a TRIGA research? reactor contaminated with $^{137}Cs\;and\;^{60}Co$ for 15 years and the non-reactive soil that was intentionally contaminated with $Cs^+\;and\;Co^{2+}$ for 3 days. It was observed that because of an aging effect on $^{137}Cs$, the efficiency of removing it decreased. $H_{2}SO_4$ used as an additive to increase the removal efficiency showed a higher removal capability than other chemicals for both $^{137}Cs\;and\;^{60}Co$. The efficiency of removing radionuclides from the radioactive soil in the column was proportional to the capability of the added chemical to extract radionuclides. It took 10 days to achieve a $54\%$ removal of $^{137}Cs$ and a $97\%$ removal of $^{60}Co$ from the soil. The volume of the soil wastewater discharged from the soil column by the electrokinetic method was $20\%$ below that for soil washing.