• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.453.1-453
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• 2001

• The Korea Swine Journal
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• v.19 no.11 s.219
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• pp.96-99
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• 1997

• Nuclear industry
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• v.28 no.12
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• pp.99-113
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• 2008

• 프린팅코리아
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• s.25
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• pp.96-99
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• 2004

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.179-185
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• 2000

In this study, we examined the movement of chlorophenol as a precursor of the dioxin in the after-combustion to minimize the creation and emission of dioxin in a municipal waste incinerator. The CPs was injected to the electric incinerator in temperature $300{\sim}500^{\circ}C$, using $N_2$ gas to control the reaction time, The oxygen quantity supplied into the $CP_s's$ isomer combustion was added with the value of experience formula. When the space velocity in reactor was 60~80/sec, the removal efficiency of CP was obtained in the presence of Mo-V catalyst and non catalyst. The efficiency in non-catalyst was 74% to 80% mono-CP, di-CP 55~66%, tri-CP 50~58%, while mono-CP 90~99.9%, di-CP 96~97%, tri-CP 76~99% in a catalyst. Consequently, it was shown that these were 20~30% more efficienct than those.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.403-409
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• 2018

Inconel 713C which of a commercial Ni super alloy have the composition of 70 % Ni, 12 % Cr, 6 % Al and 4 % Mo. Mo is very expensive and have some economic value to recover in the alloy. In this study, liquid-liquid exraction(solvent extraction and stripping) has been performed to separate Mo from the synthetic leaching solution of spent Inconel 713C alloy and prepare to Mo powder by dying, evaporation and heat treatment. The experiments were conducted by using synthetic leaching solution which was prepared $NaMoO_4$ $2H_2O$ by dissolved in distilled water. Alamine336 and Cyanex272 dissolved in kerosene were used as extractants. The extraction percentage of Mo by Alamine336 is 99 % in the condition of the range of pH 1 to 4 and 1 % of concentration of Alamine336. The stripping solutions are used by HCl, $H_2SO_4$ and $HNO_3$ solutions and the concentrations were controlled by distilled water. The concentrations of HCl, $H_2SO_4$ and $HNO_3$ as stripping solutions are increased, the stripping percentages of Mo are increased and the stripping percentage of Mo by $HNO_3$ is higher than other stripping solutions. After liquid-liquid extraction and heat treatment, $MoO_3$ powder which of the purity of 97.5 % was prepared.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3235-3241
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• 2022

The Korea Atomic Energy Research Institute (KAERI) is planning the construction of the KIJANG Research Reactor (KJRR) for stable supply of ⁹⁹Mo. The Fission ⁹⁹Mo Production Process (FMPP) of KJRR produces solid waste such as spent uranium cake and alumina cake, and liquid waste in the form of intermediate level liquid waste (ILLW) and low level liquid waste (LLLW). This study thus established the operating range and optimum operating conditions for the cementation of ILLW from FMPP. It also evaluated whether cement waste form samples produced under optimum operational conditions satisfy the waste acceptance criteria (WAC) of a disposal facility in Korea (Korea radioactive waste agency, KORAD). Considering economic feasibility and safety, optimum operational conditions were achieved at a w/c ratio of 0.55, and the corresponding salt content was 5.71 wt%. The cement waste form samples prepared under optimum operational conditions were found to satisfy KORAD's WAC when tested for structural stability and leachability. The results indicate that the proposed cementation conditions for the disposal of ILLW from FMMP can be effectively applied to KJRR's disposal facility.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.1
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• pp.25-31
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• 2009

An analytical method of $^{99}Tc$ concentration in soil was set up and discussed considering the $^{99}Tc$ concentration in Korean soil measured with its analytical method. A selective TEVA resin was used to separate and purify the $^{99}Tc$ in the soil sample. $^{99m}Tc$ from a commercial $^{99}Mo/^{99m}Tc$ generator was used as a yield tracer for the chemical separation of $^{99}Tc$ and its problem when using $^{99m}Tc$ as a tracer was discussed. The chemical recovery yield of $^{99}Tc$ was above 70%. The optimum conditions of inductively coupled plasma mass spectrometry system(ICP-MS) were set up to determine the $^{99}Tc$ after the separation process. The minimum detectable activity(MDA) was 15 mBq/kg-dry in this analytical procedure. The $^{99}Tc$ concentration in soils of Jeju and Kori were measured in the rage of 33.73-89.16 mBq/kg-dry. Those values were less than those reported in other countries and seemed to be originated from atmospheric fallout.

• Resources Recycling
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• v.20 no.5
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• pp.40-45
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• 2011

We carried out to investigate the refining effect of molybdenum by Ar-H$_2$ vacuum arc melting(VAM) process for recycling Mo scrap. The purity of the Mo metals refined by VAM was evaluated using glow discharge mass spectromety(GDMS). From the result of GDMS, most impurities in the Mo metals except for W were removed by Ar-H$_2$ VAM down to a few mass ppm levels. The purity of the refined molybdenum scrap was improved up to 4N5(99.995%) from 3N(99.95%) of the initial Mo scrap. The amount of gaseous impurities such as C, N, and O in Mo scrap were decreased from 1290 ppm to 132 ppm. As a result, it is considered that a possibility of refining and cost-effective method for recycling Mo scrap by Ar-H$_2$ vacuum arc melting process was confirmed in this study.

• Analytical Science and Technology
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• v.6 no.3
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• pp.289-296
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• 1993

The formation of Mo(VI)-alizarin red S chelate ion and its extraction into an organic solvent by ion-pairing were studied for the separative determination of trace Mo(VI) in natural water samples. Natural water 100mL was sampled in 250mL separatory funnel. After Mo(VI)-ARS chelate ion was formed by adding 0.01M alizarin red S solution 0.5mL to the water sample of pH 4.0, 0.2% aliquat-336 chloroform solution 10mL was added and the solution was vigorously shaked for about 30 seconds to from the ion-pair between Mo(VI)-ARS and aliquat-336, completely. The solution was stood for about 90 minutes. And the organic phase was taken for the absorbance measurement of the ion-pair at 520 nm. The content of Mo(VI) in sample was obtained from the standard calibration curve. Several extraction conditions such as pH, adding amounts of alizarin red S and aliquat-336, and shaking and standing times were optimized. This procedure was applied to the analysis of river and tap waters. It could be confirmed from the recoveries of over 99% in samples spiked with a given amount of Mo(VI) that this method was quantitiative in the determination of trace Mo(VI) in a natural water.