• Proceedings of the Korean Nuclear Society Conference
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• 1996.11b
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• pp.583-589
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• 1996

원자력발전소에서 발생되는 방사성폐기물들은 폐기물형태 및 방사능 농도가 다양하며 영구처분장으로 이송전까지는 발전소내의 임시 저장고에 안전하게 보관, 관리하고 있다. 생성된 폐기물드럼내에는 감마방출핵종을 비롯하여 알파 및 베타방출 핵종들이 균질 또는 비균질하게 존재하고 있으며 방사능의 세기나 폐기물의 특성에 따라 안정화시키거나 압축처리하여 드럼에 담겨져 있기 때문에 일반적인 파괴분석에 의한 화학분석법으로는 작업자의 피폭, 시료의 대표성 선정 및 장시간의 화학처리 시간소요 등으로 핵종분석이 곤란하다. 따라서 본 논문은 일반적으로 감마핵종분석시 흔히 사용하고 있는 고순도게르마늄(HPGe) 검출기를 이용하여 드럼의 감마핵종농도를 분석하는 방법과 장치의 개발에 대해 언급하였으며 알파나 베타핵종과 같이 직접 분석이 곤란한 핵종들은 각 폐기물드럼내에 존재하는 Co-60이나 Cs-137과의 상관관계를 미리 예측한 척도인자 (scaling factor)를 이용하여 간접적으로 구하는 방법을 사용하고 있으나 본 논문에서는 드럼으로부터 감마핵종만을 분석하는 방법에 대해서만 언급하였다. 또한 핵종분석시스템의 최적 운전조건을 도출하기 위해 드럼회전테이블의 속도결정 및 모의드럼을 이용한 방사능측정 등을 통해 핵종 농도 분석시의 오차를 30% 이내로 유지할 수 있었다.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.75-81
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• 1996

최근 포괄적 핵확산금지조약(CTBT)의 협정은 핵활동 감시의 목적으로 핵실험으로 인하여 발생되는 지진, 대기 방사성 핵종, 수중음향 그리고 초저음파 등을 종합운영하는 감시 시스템의 구축에 초점을 두고 있다. 1995년에 개최된 제네바군축회담/핵실험금지 특별위원회(CD/NTB/WP.224)에서 방사능 감시 전문가들은 대기중의 방사성 핵종의 검출, 핵실험 여부의 식별 그리고 핵실험 장소의 위치를 확인하기 위하여 국제 방사핵종 측정시스템(IRMS)을 설치할 것에 동의하였으며, 방사성 핵종의 검출은 핵실험 감시에 필수적인 수단으로 결정하였다. 본 연구에서는 대기중의 입자 방사능을 검출 시스템을 대기중의 공기를 흡입하기 위한 High Volume Air Sampler(HVAS)와 대기중의 방사능을 채집한 Filter Paper을 압축하는 Filter Paper 압축기 그리고 HpGe 검출시스템의 3 부분으로 구성하였다. HVAS와 Filter Paper 압축기는 본 연구의 수행을 위하여 자체 설계·제작하였으면, HpGe 검출시스템은 ORTEC사의 모델 CFG-PH-2를 사용하였다. HVAS에 의하여 Filter Paper애 채집된 시료를 측정하여 Raw Data를 분석하였다. 추후 본 시스템은 CTBT 원거리 대기 입자방사능 감시시스템의 네트워크에 연결하여 핵실험 감시를 위한 역할을 궁극적으로 검토중에 있다.

• Journal of Radiation Protection and Research
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• v.33 no.3
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• pp.121-126
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• 2008

Radioactivities of the stack air effluents from the Advance Fuel Science Building (AFSB) at KAERI have been investigated and evaluated. In this AFSB, nuclear fuels for the HANARO research reactor have been fabricated and the advanced nuclear fuels have been studied. A stack air monitoring system has been continuously operating to monitor the stack air effluents from the facility to protect the environment. As the results of the periodical radioactivity measurement and both the gamma and alpha spectrometry for the millipore filters taken from the stack air monitor from January until March 2008, a trace amount of primordial $^{40}K$ and the short-lived decay products of natural borne $^{222}Rn$ and $^{220}Rn$ have been detected. However, the radioactivities have rapidly decayed to the level below the Minimum Detectable Activity (MDA) of the counting system. Therefore, it was evaluated that no uranium isotopes have been released to the atmosphere from the stack of the AFSB at KAERI.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.3
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• pp.281-299
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• 2017

The inventory management of radionuclides is essential for the safe management of disposal facilities. In this study, we compared the activity of dry active waste predicted using the generated waste data and that measured for the accepted waste in the disposal facility. For very low level waste, the measured activity was higher than the predicted activity for $^{137}CS$, $^{90}Sr$, $^{99}Tc$ and $^{129}I$. In low level waste, the predicted activity was higher than the measured activity for all radionuclides. We also evaluated the variation in the predicted quantity and total activity of each level of dry active waste through a sensitivity analysis on a scaling factor. This result will contribute to the construction of a Safety Case and safe operation of disposal facilities.

• Membrane Journal
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• v.9 no.2
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• pp.132-139
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• 1999

Solid scintillation proximity membranes were prepared for measuring the amount of radioactivity in laboratories contaminated by the radionuclide of $^3H$-cortisol. The membranes, consisting of polysulfone as a polymer matrix and cerium activated yttrium silicate as a fluor, were used to monitor the amount of radioactivity without the aid of a scintillation cocktail required for the conventional wipe test. The test results of the cocktail-free wipe test showed that the prepared membranes were efficient to monitor radionuclide-contaminated areas with the good counting ability as well as with the decrease of overall production of radioactive waste. On the other hand, solvent treatment of the prepared membranes could induce a significant variation of membrane morphology, but the counting efficiency of the solvent-treated membranes was not improved than that of the untreated one.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.142-146
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• 2004

지하수중에 존재하는 극미량의 환경방사성 동위원소를 측정하기 위한 방법을 개발하였다. 각 핵종들중 234U, 238U, 222Rn, 226Ra은 섬광액을 포함한 용매추출법을 사용하여 개별분리한 후 액체섬광계수기를 사용하여 각 핵종에서 방출되는 알파선을 검출하였다. 환경방사성 원소인 U과 Th 딸핵종의 비평형에 의한 지하수 특성 연구를 위해서 국내 지하수 중의 234U와 238U의 방사능비 측정을 대전 화강암 지역에서 채취한 지하수 시료를 ICP/MS를 사용하여 U 함량을 결정하고, 지하수에서 U을 용매추출한 후 알파전용 액체섬광계수기를 사용하여 234U와 238U의 방사능을 측정하였다.

• 대한방사선방어학회:학술대회논문집
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• 2009.04a
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• pp.268-269
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• 2009

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.1
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• pp.11-15
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• 2008

In order to transport spent resin in a high integrated container made of high density polyethylene, a method for determining transportation grade by radioactivity analysis was developed. Ratios of radioisotopes in spent resin were derived from radioactivity analysis on spent resin. Associated curie-to-dose factors were determined to estimate radioisotope inventory from surface dose rates of spent resin. From the results, Activity limit of type A package was derived to be 1.19 TBq for HIC, and the corresponding surface dose rate was found to be 124.2 mSv/h.

• 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 Journal of the Petrological Society of Korea
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• v.17 no.3
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• pp.179-190
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• 2008

The distribution characteristics of some major environmental radionuclides ($^{40}K$, $^{228}Ac$, $^{226}Ra$, $^{222}Rn$) and U in rocks, soils and soil gas were studied at Geumjeong-Gu, Busan, Korea. The activities of radionuclides in granitic rocks are decreased in the odor of $^{40}K$>thorium decay series>uranium decay series. This reveals that Th was relatively more enriched in granitic rocks than U. The U content and activity of $^{226}Ra$ and $^{228}Ac$, however, don't reflect the fractionation sequence of granitic rocks in the study area. The activities of all these radionuclides and U content in soils are generally higher than in rocks, and their distribution in rocks, soils and soil gas show very low co-relationship. These facts indicate that the activities of radionuclides in soil and soil gas were greatly affected by leaching and adsorption properties of the radionuclides and their parents during weathering and pedogenetic process rather than their concentrations in parent rocks.