• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.84-85
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• 2009

• 대한방사선방어학회:학술대회논문집
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• 2010.04a
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• pp.178-179
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• 2010

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2012.05a
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• pp.391-392
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• 2012

• Analytical Science and Technology
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• v.24 no.6
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• pp.414-420
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• 2011

In this study, radiation measurement system has been investigated to set up for the radioisotopes analysis in the radioactive waste samples after selecting the radiation counters of alpha beta and gamma nuclides. The counting efficiencies for alpha, beta and gamma measurement systems were calibrated. To obtain stability of the radiation detectors, quality control program has been established. Also, minimum detectable activities (MDAs) depending on the type of samples were calculated for increasing the confidence level for analytical result.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.1
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• pp.1-7
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• 2005

Anion exchange chromatography and HDEHP extraction chromatography using DTPA-lactic acid as an eluent were applied in series for the separation of $^{241}$Am and $^{244}$Cm in radwaste samples. The separated elements were determined by electrodeposition at the sodium hydrogen sulfate-sodium sulfate buffer solution followed by alpha-spectrometry. The recovery yields of $^{241}$Am and $^{244}$Cm were 85.2$\pm$$15.3\%$, respectively, from the synthetic solution of spent nuclear fuel sample. The amounts of 241Am and 2440m determined in radwaste sample solutions of condensate bottoms were at the range of 1.5-1.9 Bq/g and -1.7 Bq/g, respectively.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2_spc
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• pp.227-235
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• 2020

In this study, we discussed the limitations of gross alpha measurements for the characterization of radioactive wastes produced in nuclear facilities through experimental tests and Monte Carlo N-particle transport simulations. The determination of gross alpha is essential for the disposal of radioactive waste produced in nuclear facilities in Korea. The measurements of gross alpha are easy to perform and yield rapid analytical results, but it cannot be used for quantitative analysis. The error of counting efficiency for gross alpha with various masses of the deposit on planchets using KCl and ²⁴¹Am was determined. The relative deviation of the counting efficiency in samples having the same mass was 20%. Uranium was extracted from the soil through acid leaching and extraction chromatography, and the concentration of U determined by inductively coupled plasma-mass spectrometry (ICP-MS) was compared with the results for gross alpha. The gross alpha was underestimated by 50% compared to the U concentration by ICP-MS. The counting efficiency depended on the energy from the alpha emitters, which differed by up to three times in determination of the counting efficiency depending on the kinds of alpha radionuclides of interest. Therefore, the gross alpha is not compatible with the sum of radioactivity for each alpha emitter and is suitable as a screening method.

• Analytical Science and Technology
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• v.12 no.5
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• pp.428-435
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• 1999

A method for measuring Rn-222 and Ra-226 in aqueous sample using liquid scintillation counting technique has been studied. The Rn-222 was extracted easily from the water sample (10 mL) by 12 mL of xylene based organic scintillant. After radioactive equilibrium between Rn-222 and its alpha emitting decay products for three hours, the alpha activity from Rn-222 and its decay products were measured in a scintillation vial using the Wallae $1220^{TM}$ Quantulus liquid scintillation counter. Ra-226 concentration in aqueous sample was determined, after isolation of Ra-226 from the sample matrix, by extraction the ingrowth of the Rn-222 and its alpha emitting decay products with xylene based organic scintillant. The optimum pulse-shape analysis (PSA) value was evaluated by the figure of merit (FM) criterion. Minimum detectable activity (MDA) is about 0.14 Bq/L (3.78 pCi) for the region of Rn-222 and its alpha emitting decay products and 0.06 Bq/L (1.63 pCi) for the region of Po-214 respectively, with 200 min, counting time at PSA level 100 in the low-diffusion polyethylene vial and xylene based cocktail solution. Experiment on the optimum sample-cocktail volume ratio, the influence of agitation and the diffusion of radon from vial were carried out.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.67-68
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• 2003

라돈은 일반적으로 가장 잘 알려진 천연 방사성핵종 중 하나로서 무향 무색의 불활성기체이며 붕괴과정에서 알파입자를 방출한다. 라돈에 의한 피폭선량은 라돈붕괴에 의해 생성된 라돈자손이 호흡기관 표면에 침착되어 방출하는 알파선에 기인한다. 따라서, 피폭선량에 주로 기인하는 것은 라돈 자신이 아니라 그의 단 반감기 라돈자손들이다. 이처럼 라돈은 잘 알려진 폐암 유발원으로서 고농도의 라돈에 장기간 노출되는 경우 폐암을 유발할 수 있다. UNSCEAR 보고서(1993)는 자연 환경중에서 인간이 받는 연간 총 피폭선량인 2.4 mSv중 약 50%에 해당하는 1.15 mSv가 라돈과 그 자손에 의한 것이며 대부분 옥내에서의 호흡에 의해 비롯된다고 평가하고 있다. (중략)

• Journal of the Korea Institute of Building Construction
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• v.17 no.1
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• pp.15-21
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• 2017

WHO reported that millions of people die every year because of diseases induced from environmental pollution. In 2012, approximately 7 million people were killed due to air pollution. Major cause of such pollution includes toxin, chemical waste, radiation and air pollution. Therefore, the significance and interest to indoor air quality has been continuously increased. Especially, the interest in radon, the ARC group 1 carcinogen, is rapidly increasing, and banning the use of construction materials that release radon, repairing aged buildings, and developing ventilators. To reduce the level of radon gas was inflowed to indoors and outdoors, this study is to research and develop a radon gas absorption board using absorbents. The absorbents utilized to absorb the radon gas were porous diatomite, natural zeolite, 4A zeolite and 13X zeolite and employed bentonite and illite, montmorillonites with the property of exchanging anions. As the main binder, magnesium oxide was used, with a content of 25% magnesium chloride.

• Journal of Radiation Protection and Research
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• v.20 no.1
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• pp.16-24
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• 1995

Assesment of dose equivalent given by inhaled $^{222}Rn$ and its progeny has been carried out based on the concentrations of $^{222}Rn$ and its daughters in indoor air, and equilibrium factor between them measured by charcoal canister method and alpha spectrometry. Assuming the occupancy factor to be 0.8, and breathing rate to be $0.75m^3\;h^{-1}$ for public and $1.2m^3\;h^{-1}$ for occupational exposure, respectively, the regional lung dose 대valent and the resulting annual effective dose equivalent due to the inhalation of $^{222}Rn$ and its daughters in indoor air were evaluated by use of three different lung models, namely, Jacobi-Eisfeld, James-Birchall and ICRP model.