• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.154-155
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• 2009

• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.150-151
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• 2009

• 대한방사선방어학회:학술대회논문집
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• 2010.04a
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• pp.168-169
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• 2010

• Applied Chemistry for Engineering
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• v.21 no.4
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• pp.475-478
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• 2010

Fluorinated polymeric membranes were prepared by direct surface modification of PDMS with fluorine gas ($50{\sim}2000\;{\mu}mol/mol$ in nitrogen). The formed fluorinated polymeric membranes were characterized by FT-IR spectroscopy, GC (Gas chromatography), atomic force microscopy, and scanning electron microscopy. Direct fluorination resulted in the change of permeability and selectivity of various gases (pure gases such as $CO_2$, $O_2$, $N_2$, $C_2H_4$, mixture of He, Ne, Kr, Xe) through PDMS membranes. Fluorination resulted in the maximum 50% increase of selectivity through PDMS membrane.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.301-308
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• 2018

Anthropogenic radioactive noble gases formed by nuclear fission are significant indicators used to monitor the nuclear activity of neighboring countries. In particular, radioactive xenon, owing to its abundant generation and short half-life, can be used to detect nuclear testing, and radioactive krypton has been used as a tracer to monitor the reprocessing of nuclear fuels. Released radioactive noble gases are in the atmosphere at infinitesimal amounts due to their dilution in the air and their short half-life decay. Therefore, to obtain reliable and significant data when performing measurement of noble gases in the atmosphere, the minimum detectable activity (MDA) for noble gases should be defined as low as possible. In this study, the MDA values for radioactive xenon and krypton were theoretically obtained based on the BfS-IAR system by collecting both noble gases simultaneously. In addition, various MDA methods, confidence level and analysis conditions were suggested to reduce and optimize MDA with an assessment of the factors affecting MDA. The current investigation indicated that maximizing the pretreatment efficiency and performance maintenance of the counter were the most important aspects for Xe. In the case of Kr, since sample activities are much higher than those of Xe, it is possible to change the target MDA or to simplification of the analysis system.

• 대한방사선방어학회:학술대회논문집
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• 2011.11a
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• pp.288-289
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• 2011

• 대한방사선방어학회:학술대회논문집
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• 2009.04a
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• pp.196-197
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• 2009

• The Journal of Engineering Geology
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• v.26 no.4
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• pp.551-559
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• 2016

The chemical composition and noble gas isotopes of 10 deep groundwater samples were analyzed to know the circulation of groundwaters in the Yangsan fault and the Gampo fault. The chemical types of groundwaters show the $Ca-HCO_3$ type and $Ca-SO_4(Cl)$ type, and show indistinct relationship with geology. Noble gas isotopic data of most groundwaters were plotted along the air-crust mixing line on $^3He/^4He$ vs. $4^He/^{20}Ne$ diagram, and show dominant $^3He$ of air origin except one sample that shows helium mixing of crust origin. This indicates that groundwater actively circulates along fault, and fault could not play an role of upward pathway of a deep-seated helium gas. A comparatively high $^4He$ indicates that groundwater flows in an aquifer assuring relatively enough water-rock interaction.