• Korean Journal of Soil Science and Fertilizer
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• v.4 no.1
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• pp.55-66
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• 1971

A method for the identification of and measurement of beta activity due to $^{40}K$ have been developed in this institute. The method is based on the principle of : $$G(t)=\frac{A}{A_{\infty}}=1-e^{-{\eta}t}$$ where: G(t)=fraction of maximum activity A = counting rate of thickness $A_{\infty}$= saturation activity ${\eta}$= mass absorption coefficient of $^{40}K$ By this technique, total beta activity in 92 Korean paddy soil samples collected from various part of the country, have been determined and the results of this analysis reported in this paper. Most of the beta activity in soils have been accounted for to be due to $^{40}K$.

• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.59-67
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• 1998

토양중 침투성 살충제 carbofuran과 제초제 petilachlor의 용탈행적을 구명하기 위하여 물리화학적 성질이 상이한 2종의 논토양으로 충전된 토양 column (내경 5cm ${\times}$ 길이 30cm)에 $^{14}C$-표지 화합물을 각각 처리한 후 벼 (Oryza sativa L.)를 생육시키면서 벼를 심지 않은 경우를 대조구로 하여 8주 동안 주당 95.2 ml씩 용탈시켰다. Carbofuran의 경우 토양 column에서 용탈된 $^{14}C$ 방사능의 양은 벼를 재배하지 않은 토양 A와 B에서 각각 총처리 방사능의 74.8와 92.3%였으며, 벼를 재배한 토양에서는 각각 45.1%와 69.7%였다. 반면에 petilachlor의 경우 벼를 재배한 토양 column에서는 각각 총처리 방사능의 2.4%와 5.0%가 용탈되었으며, 벼를 재배한 경우는 각각 3.1%와 8.2%가 용탈되었다. 토양에 처리한 [$^{14}C$]화합물 모두 벼의 생육유무에 관계없이 양이온치환용량, 유기물 및 점토의 함량이 적은 토양 B에서 $^{14}C$ 방사능의 용탈이 증가되었다. 토양 column중 carbofuran의 이동성은 매우 높은 반면에 petilachlor는 매우 낮았으며, 이는 그들의 토양흡착과 수용성에 기인된 것으로 판단된다.

• Applied Biological Chemistry
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• v.41 no.3
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• pp.253-257
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• 1998

Behaviour of a fungicide $^{14}C-propiconazole$ was investigated in a field lysimeter of sandy loam soil. At 15 days after rice-seedling transplanting, $^{14}C-propiconazole$ was treated on the soil surface at the rate of 0.12 kg/10a. The cummulative $^{14}C-radioactivity$ in the leachate from the lysimeter soil was 4.4% of the applied $^{14}C$ for 16 weeks. Most radioactivity detected in leachate was in the form of parent compound. At the end of lysimeter experiment. $^{14}C$ radioactivity in lysimeter soil was 76.5% of the applied $^{14}C$ and more than 97% of $^{14}C$ in soil remained in the top 20 cm. The percent of $^{14}CO_2$ evolved from lysimeter soil was 7.8% of the applied $^{14}C$. The radioactivity remained in the rice straw after harvest was 7.2% of the applied $^{14}C$, while less than 0.1% of the applied $^{14}C$ was detected in flag leaf, ear, chaff and hulled rice, respectively.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.4
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• pp.245-251
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• 2004

Soil washing equipment was developed for decontamination of radioactively contaminated soil generated during normal operation or decommissioning and verification experiments were performed. Decontamination effciency above $80{\%}$ was achieved. In case of low radiation level and large particle size, decontamination efficiency was higher. According to the ratio of volume of water to soil quantity, decontamination efficiency was higher in case of high radiation level. Re-decontamination using decontaminated soil was effective in case of small particles. Using soil washing equipment, radioactivity of contaminated soil generated in nuclear power plant can be decreased and volume of soil for disposal can be decreased. And this equipment can be used in decommissioning.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.77-78
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• 2002

원자력시설이나 원자력발전소에서 사고가 발생하여 대기로 방출된 방사능물질은 두 가지 주요경로를 통해 인체노출이 일어난다 첫째는 지역내 대기중에 존재하는 방사성물질이 인체의 호흡이나 피부 등을 통해 체내로 흡입되는 직접적인 노출 (Direct Exposures)이고 다른 하나는 방사능물질이 대기로부터 주변의 토양에 침적하고 이러한 토양에서 재배된 오염된 농작물들 (쌀, 보리, 밀, 또는 과일, 채소)을 인간이 섭취하거나, 방사능물질에 오염된 목초로 키운 축산물(소, 돼지, 닭 등)과 이들로 생산하는 제품들(우유, 고기, 달걀 등)을 인간이 섭취함으로써 이루어지는 보다 간접적인 인체노출(Indirect Exposures)이 있을 수 있다. (중략)

• Korean Journal of Environmental Agriculture
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• v.18 no.3
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• pp.215-220
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• 1999

Behaviour of a fungicide $^{14}C-propiconazole$ was investigated in a rice plant grown-lysimeter soil. The lysimeter was composed of soil cores of silty clay. $Propiconazole(Tilt\;250^R\;EC)$ plus $^{14}C-labeled$ propiconazole was applied on the surface of lysimeter soil at a rate of 0.12kg/10a after rice transplanting. The application was done consecutively for two years. The behaviours of propiconazole in the lysimeter soil were investigated by measuring the amounts of $^{14}C-leachate$, $^{14}CO_2$, the residues distributed in each soil segment and taken up by rice plants. The relative amounts of $^{14}C$ leached from the lysimeter were the background level of the applied $^{14}C$ throughout expeiment. The amounts of $^{14}CO_2$ evolved from the lysimeter were 5.7 and 7.8% of the original $^{14}C$ in the 1st and 2nd treatment, respectively. The amounts of volatile substances soil were the background level throughout experiment, which indicated that propiconazole was stable chemically in the experimental condition. The $^{14}C-activities$ absorbed and translocated into rice plants were 3.7 and 7.6% in 1st and 2nd treatment, respectively. The $^{14}C-activities$ in the soil layer of the lysimeter was distributed mainly in the depth of 0 to 20cm, which suggested propiconazole did not have the risk of groundwater contamination.

• Analytical Science and Technology
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• v.17 no.6
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• pp.514-519
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• 2004

Soil samples collected from around the BOMARC Missile Site were measured for their activity concentrations and isotopic ratios of Pu and Am isotopes with particle sizes. The activity concentrations of Pu and Am in the BOMARC soil were remarkably higher than the fallout levels, and the activities decreased nearly exponentially with an increasing particle size of the soil due to a decreasing surface area. The activity ratios of Pu-238 / Pu-239, 240, Pu-241 / Pu-239, 240 and Am-241 / Pu-239, 240 observed in the BOMARC soil were much lower than those attributed to the nuclear reprocess plants and the Chernobyl fallout. Also, the atomic ratio of Pu-240 / Pu-239 in the BOMARC soil was remarkably lower than the fallout value influenced by the nuclear weapons testing and the Chernobyl accident. The atomic ratio of Pu-240 / Pu-239 was so close to the value of the weapons grade Pu released from the crash of a B52 plane in the Thule of the Greenland, such that the Pu isotopes detected in the BOMARC soil could have originated from the weapons grade plutonium.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.191-192
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• 2003

원자력시설의 사고시 대기중으로 누출된 방사성물질에 의해 오염된 토양으로부터 재배된 농작물로 인한 인체노출은 각종 환경오염물질에 의한 인체영향 연구결과에 보듯이 직접적인 방사능에 의한 인체노출 못지 않게 상당히 중요하다. 이러한 섭식경로를 통한 노출은 각 나라마다 서로 다른 토양조건 및 작물체종류의 다양성등 다른 양상을 보이고 있어, 연구가 수행된 미국이나 유럽등지의 평가방법을 그대로 사용하면 국내의 토양에서 재배되는 농작물이나 이를 이용한 축산물에 따른 한국인의 독특한 섭취양상을 충분히 고려하여 평가하기 어려울 수 있다. (중략)

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.151-157
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• 2005

For the treatment of regulatory clearance of the soils, a procedure for the radionuclides and radioactivity concentration analysis is under development. A strategy for soil sampling including random sampling after homogenization and standardization was set up. Statistical representativeness is considered for not only sampling strategy but also sample size. In this study, designed sample size was designed with confidence interval and error bound of soil using the pilot samples which were taken following the sampling strategy.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.405.1-405
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• 2002