• Resources Recycling
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• v.20 no.3
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• pp.48-54
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• 2011

Sulphuric acid leaching was conducted to extract the metal values from spent refinery catalyst. More than 95% of Ni and V and 30% of Mo could be leached out in 1 M sulphuric acid and 1 hr of leaching time. The decrease in Mo leaching was due to typical characteristic of Mo matrix. The activation energies of the leaching reactions showed the dissolution process follows a diffusion control mechanism. In order to leach out all Mo, further the leaching experiments were conducted with sulfur free spent refinery catalyst. For sulfur free spent refinery catalyst, a two step process of leaching with 1 M sulphuric acid followed by sodium carbonate washing showed better leaching than a two step leaching process with sodium carbonate followed by sulphuric acid washing, with almost 99% leaching of Ni, Mo and V. Solvent extraction using LIX 841 were conducted for a leach liquor containing Ni, 2 g/L; V, 9 g/L, Mo, 0.6 g/L. More than 98% of Mo was extracted from the leach liquor at A:O ratio of 5:2 in a 2 stage process. Similarly V was extracted at A:O ratio of 5:3 in a 2 stage process with 82% of total V extraction.

• Resources Recycling
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• v.27 no.4
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• pp.16-22
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• 2018

Inconel713C which of a commercial Ni super alloy have the compositions of 70 wt.% Ni, 12 wt.% Cr, 6 wt.% Al and 4 wt.% Mo. In this study, solvent extraction has been performed to separate Mo from the synthetic leaching solution, formation of Inconel713C alloy similarly and is found the optimum conditions of recovery of Mo from the leaching solution. The effects of some variables, such as the nature and concentration of the extractants, $H_2SO_4$ concentrations, and the presence of impurities were investigated. The extraction percentage of Mo by Cyanex272 is 96% in the condition of pH 1 and 4% of concentration of Cyanex272 but Alamine336 is 99% in the condition of the range of pH 1 to 4 and 1 wt.% of concentration of Alamine336. In the case of Alamine336, the extraction percentage of Mo is increased by increasing of the concentration of Alamine336. The optimum condition of this experiment is pH 1 in aqueous phase, 1% concentration of Alamine336 and activation ratio of $H_2SO_4$ 1:0.5.

• 기계와재료
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• v.6 no.1 s.19
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• pp.99-111
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• 1994

• Korean Medical Education Review
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• v.3 no.2
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• pp.93-99
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• 2001

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.60-60
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• 2002

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.06a
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• pp.407-408
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• 2009

• 연구논문집
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• s.29
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• pp.91-99
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• 1999

Fatigue crack growth behaviors of Cr-Mo steels developed recently for thick-wall pressure vessel were investigated. Experiments in accordance with ASTM E647 standard were performed for 1/2 inch CT specimens of $2^(1/4)$Cr-1Mo and 3Cr-IMo steels in gaseous environments, hydrogen gas of 10 atm, 1 atm and argon gas of 1 atm. Fatigue crack growth rates were observed and effects of gaseous hydrogen and argon on the crack growth behavior were discussed.

• Nuclear Engineering and Technology
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• v.34 no.6
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• pp.533-544
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• 2002

The neutron induced nuclear data for Mo-95, Tc-99, Ru-101 and Rh-103 was calculated and evaluated in the fast energy region. The energy dependent optical model potential parameters were extracted based on the recent experimental data and applied up to 20 MeV. The s-wave strength function was calculated from the parameters. Spherical optical model, statistical model in equilibrium energy, multistep direct and multistep compound model in pre-equilibrium energy and direct capture model were used in the calculation. The theoretically calculated cross sections were compared with the experimental data and the evaluated files The model- calculated total and capture cross sections were in good agreement with the reference experimental data. The direct capture contribution improved the capture cross sections in pre- equilibrium region. The evaluated cross section results were compiled to ENDF-6 format and will improve the ENDF/B-Vl.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.193-198
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• 1998

Fission Moly 생산을 위한 조사시설로 HANARO가 사용점에 있어서 충분한 타당성을 갖는지에 대해 원자로 운전중 표적장전에 따른 노심반응도의 영향, 표적의 최대 표면 열출력밀도, Mo-99 생산능력 측면에서 평가하였다. 그 결과 운전중 표적 장전으로 인한 반응도가(reactivity worth)가 약 0.2 %Δ$\rho$정도로 제한치인 1.25 %Δ$\rho$보다 현저히 작고, 최대 표면 열출력밀도 또한 2.76 Mw/$m^2$보다 현저히 작음을 볼 수 있었다. 또한 OR공 한 개만을 사용한다. 할지라도 Mo-99의 상업생산 목표를 충분히 만족시킬 수 있음을 알 수 있었다 따라서 HANARO를 Fission Moly 생산을 위한 조사시설로 사용하는 것은 타당하다 할 수 있다.

• Carbon letters
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• v.13 no.2
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• pp.99-108
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• 2012

The sol-gel technique has been studied to fabricate a homogeneous Fe-Mo/MgO catalyst. Ambient effects (air, Ar, and $H_2$) on thermal decomposition of the citrate precursor have been systematically investigated to fabricate an Fe-Mo/MgO catalyst. Severe agglomeration of metal catalyst was observed under thermal decomposition of citrate precursor in air atmosphere. Ar/$H_2$ atmosphere effectively restricted agglomeration of bimetallic catalyst and formation of highly-dispersed Fe-Mo/MgO catalyst with high specific surface-area due to the formation of Fe-Mo nanoclusters within MgO support. High-quality thin-multiwalled carbon nanotubes (t-MWCNTs) with uniform diameters were achieved on a large scale by catalytic decomposition of methane over Fe-Mo/MgO catalyst prepared under Ar-atmosphere. The produced t-MWCNTs had outer diameters in the range of 4-8 nm (average diameter ~6.6 nm) and wall numbers in the range of 4-7 graphenes. The as-synthesized t-MWCNTs showed product yields over 450% relative to the utilized Fe-Mo/MgO catalyst, and indicated a purity of about 85%.