• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.384.1-384
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• 2001

• Bulletin of the Korean Chemical Society
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• v.16 no.8
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• pp.683-685
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• 1995

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.155-159
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• 2001

Beta radiation is measured for an environmental monitoring purpose or for an internal radiation exposure monitoring of nuclear power plant's worker. In korea, strontium 89 and strontium 90 is measured for an environmental monitoring purpose. Also tritium and carbon 14 contained in urine is measured for an internal radiation exposure monitoring of nuclear power plant's worker. Because above isotopes emits low energy beta radiations having a wide range of energy, very complicated isotope separation preprocess is needed. In this study, two mixed beta emitting isotopes are measured simultaneously using a liquid scintillation counter(LSC) and analyzed by using a developed statistical method. Banded least square method is used to analyze the mixed spectrum, and the goodness-of-fitness test is proposed. Test results show that the developed procedure can be very useful for analyzing a mixed beta emitting isotopes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4696-4703
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• 2011

Tetraazamacrocyclic ion-exchangers, 1,4,8,11-tetraazacyclotetradecane bonded Merrifield peptide resin(TDM), 1,4,8,12-tetraazacyclopentadecane bonded Merrifield peptide resin(TPM) were prepared, and the ion-exchange capacity of these TDM and TPM were characterized. The distribution coefficients in various conc. of NH4Cl for magnesium with ion exchangers were determined by using the batch method. We found the isotope separation factors on new prepared tetraazamacrocyclic ion-exchangers bonded Merrifield peptide resin(TDM, TPM). The isotope separation of magnesium was determined by using of breakthrough method of column chromatography.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.2 no.2
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• pp.84-95
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• 2016

Considerably increasing interest in using the theranostic isotopes/ isotope pairs of radiometals like $^{44/47}Sc$ and $^{64/67}Cu$ for diagnosis and/or therapeutic applications in the nuclear medicine procedures necessitates its reliable production and supply. Separation and purification of no-carrier-added (NCA) isotopes from macro quantitates of the irradiated target matrix along with other impurities is a cardinal procedure amongst several other steps involved in its production. Multitudinous methods including but not limited to liquid-liquid (solvent) extraction, extraction chromatography (EXC), ion exchange, electrodeposition and sublimation are routinely applied either solitarily or in combination for the separation and purification of radioisotopes depending on their production routes, radioisotope of interest and impurities involved. However, application of EXC though has shown promises towards the numerous separation techniques have not received much attention as far as its application prospects in the field of nuclear medicine are concerned. Advances in the recent past for application of the EXC resins in separation and purification of the several medically important radioisotopes at ultra-high purity have shown promising behavior with respect to their operation simplicity, acidic and radiolytic stability, separation efficiencies and speedy procedures with the enhanced and excellent extraction abilities. In this mini review we will be talking about the recent developments in the application and the use of EXC techniques for the separation and purification of $^{44/47}Sc$ and $^{64/67}Cu$ for medical applications. Furthermore, we will also discuss the scientific and practical aspects of EXC in the view of separation of the NCA trace amount of radionuclides.

• Analytical Science and Technology
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• v.31 no.3
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• pp.134-142
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• 2018

The uranium isotopic ratio in environmental samples around nuclear facilities is important because it reveals information regarding illegal activities or anthropogenic pollution. Determination of uranium isotopes, however, is a challenging task requiring much labor and time because of the complex separation procedures and lengthy process. In this study, a rapid determination method for uranium isotopes in environmental samples was developed using. The sample was completely decomposed using the alkali fusion method. The separation procedure using extraction chromatography (UTEVA) was simplified in a single step without any further removal process for Si and major matrix elements. The established method can be completed within 3 h from sample dissolution to ICP-MS measurement. Most matrix elements and uranium isotopes in the soil samples were well separated and purified. Five types of were used to assess the method's accuracy and precision for a rapid uranium analysis method. The analytical accuracy for all CRM samples ranged from 95.1 % to 97.8 %, and the relative standard deviation was below 3.9 %. From the analytical results, one may draw conclusions that the evaluated method for uranium isotopes using alkali-fusion, the extraction chromatography process, and ICP-MS measurements is fast and fairly reliable owing to its recovering efficiencies. Thus, it is expected that the evaluated method can contribute to the improvement of environmental monitoring ability.

• Analytical Science and Technology
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• v.18 no.6
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• pp.469-474
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• 2005

This paper presents a quantitative method of sequential separation of $^{90}Sr$, $^{241}Am$ and Pu radionuclides with an anion exchange resin and a Sr-Spec resin. The Pu isotopes were purified with an anion exchange resin. The americium and strontium fractions were separated from the matrix elements with an oxalate co-precipitation method. Americium fraction was separated from the strontium fraction with iron co-precipitation method and purified from lanthanides with anion exchange resin. Strontium-90 was purified from other hindrance elements with the Sr-Spec resin after oxalate co-precipitation. The measurement of Pu and Am isotopes was carried out by an ${\alpha}$-spectrometer. Strontium-90 was measured by a liquid scintillation counter. The radiochemical procedure of $^{90}Sr$, $^{241}Am$ and Pu radionuclides investigated in this study has been validated by application to IAEA-Reference soils.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.407-408
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• 2011

Natural boron consists of two stable isotopes 10B and 11B with natural abundance of 18.8 atom percent of 10B and 81.2 atom percent of 11B. The thermal neutron absorption cross-section for 10B and 11B are 3837 barn and 0.005 barn respectively. 10B enriched specific compounds are used for control rods and as a reactor coolant additives. In this work 2 methods for boron enrichment were analysed: 1) Gas irradiation in static conditions. Dissociation occurs due to multiphoton absorption by specific isotopes in appropriately tuned laser field. IR shifted laser pulses are usually used in combination with increasing the laser intensity also improves selectivity up to some degree. In order to prevent recombination of dissociated molecules BCl3 is mixed with H2S 2) SILARC method. Advantages of this method: a) Gas cooling is helpful to split and shrink boron isotopes absorption bands. In order to achieve better selectivity BCl3 gas has to be substantially rarefied (~0.01%-5%) in mixture with carrier gas. b) Laser intensity is lower than in the first method. Some preliminary calculations of dissociation and recombination with carrier gas molecules energetics for both methods will be demonstrated Boron separation in SILARC method can be represented as multistage process: 1) Mixture of BCl3 with carrier gas is putted in reservoir 2) Gas overcooling due to expansion through Laval nozzle 3) IR multiphoton absorption by gas irradiated by specifically tuned laser field with subsequent gradual gas condensation in outlet chamber It is planned to develop software which includes these stages. This software will rely on the following available software based on quantum molecular dynamics in external quantized field: 1) WavePacket: Each particle is treated semiclassicaly based on Wigner transform method 2) Turbomole: It is based on local density methods like density of functional methods (DFT) and its improvement- coupled clusters approach (CC) to take into account quantum correlation. These models will be used to extract information concerning kinetic coefficients, and their dependence on applied external field. Information on radiative corrections to equation of state induced by laser field which take into account possible phase transition (or crossover?) can be also revealed. This mixed phase equation of state with quantum corrections will be further used in hydrodynamical simulations. Moreover results of these hydrodynamical simulations can be compared with results of CFD calculations. The first reasonable question to ask before starting the CFD simulations is whether turbulent effects are significant or not, and how to model turbulence? The questions of laser beam parameters and outlet chamber geometry which are most optimal to make all gas volume irradiated is also discussed. Relationship between enrichment factor and stagnation pressure and temperature based on experimental data is also reported.

• Journal of the Korean Chemical Society
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• v.29 no.2
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• pp.144-150
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• 1985

For the separation of boron isotopes, aminated polystyrenedivinylbenzene ion-exchange resins were prepared by chloromethylation of styrene-divinylbenzene copolymer (DVB 10%), followed by the reaction of methylamine. During the preparation of styrene-divinylbenzene copolymer, heptane for the porous resin and toluene for the non-porous resin were used as diluent, and the pore volume of the resins was determined by mercury porosimeter. In both water and aqueous alcohol solutions, the distribution coefficient of boric acid was decreased in accordance with increasing the alcohol concentration and the number of carbon atoms in the alcohol molecules. As a result of separatioin of boron isotope with nonporous and porous resin in water solvent, the separation efficiency of porous resin is better than that of the nonporous, and the result in both water and 50% methyl alcohol solvent relevant to nonporous resin indicated that the latter was better than the former.

• Membrane Journal
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• v.34 no.2
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• pp.114-123
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• 2024

Hydrogen isotopes can be categorized into light hydrogen, heavy hydrogen, and tritium based on the number of neutrons, each of which is used in specific fields. Specifically, deuterium is of interest in the electronics industry, nuclear energy industry, analytical technology industry, pharmaceutical industry, and telecommunications industry. Conventional methods such as cold distillation, thermal cycling absorption processes, Girdler sulfide processes, and water electrolysis have their own advantages and disadvantages, leading to the need for alternative technologies with high separation and energy efficiency. In this context, membrane-based hydrogen isotope separation is one of the promising solutions to reduce energy consumption. In this review, we will present the state-of-the-art in hydrogen isotope separation using membranes and their operating principles. The technology for separating hydrogen isotopes using membranes is just beginning to be conceptualized, and many challenges remain to be overcome. However, if achieved, the economic benefits are expected to be significant. We will discuss future research directions for this purpose.