• Resources Recycling
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• v.30 no.5
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• pp.32-37
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• 2021

Thorium extraction and possible separation from monazite leaching solution was studied. Primary amine Primene JM-T was select ed for t horium ext ract ion processing. Various experiment s were t est ed and est ablished for t he t horium liquid -liquid extraction process. The screening of extractant, lower pH conditions, extractant variation and extraction isotherms construction, and finally, stripping studies were established.

• Macromolecular Research
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• v.13 no.2
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• pp.141-146
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• 2005

Calix[4]crown-6-2,4-bis(4-aminobutyl ether), which has a crown-6 moiety at the 1,3-position and amino function at the 2,4-position, was prepared as an intermediate for the subsequent synthesis of calix[4]crown-6-containing polyamide and polyimide using adipoyl chloride and 1,2,4,5-benzenetetracarboxylic dianhydride. The chemical structures were characterized by IR, $^{1}H NMR$ spectroscopy and elemental analysis, and some of their physical properties, including their thermal behavior, were examined. The ion binding characteristics of the monomer and polymers for alkali metal and alkali earth metal ions were measured by liquid-liquid extraction from the aqueous phase into the organic phase. It has been observed that polyamide has a high binding ability towards various metal cations as compared to polyimide, which showed cesium ion selectivity.

• Journal of the Korean Vacuum Society
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• v.8 no.4B
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• pp.548-555
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• 1999

The NBI (Neutral BGeam Injection) System for the Korea Superconducting Tokamak Advanced Research (KSTAR) is composed of ion sources, neutralizers, bending magnets, ion dumps, and calorimeter. The vacuum chamber, in which all of the beam line components are enclosed, is composed of differential pumping system for the effective transfer of the neutral beams. The needed pumping speeds of each of the divided vacuum chamber and the optimized gas flow rate ot the neutralizer were calculated with the help of the particle balance equations. The minimum gas flow rate to the ion sources for producing needed beam current (120kV, 65A, 78MW), the pressure distributions in the vacuum chamber for minimizing re-ionization loss, and the beam loss rate on the beam line components were used as the input in the calculation. Also the scenario for short pulse operation was determined by analysing the time dependent equations. It showed that beam extraction during less than 0.5 sec could be made only with TMP.

• Carbon letters
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• v.5 no.3
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• pp.118-126
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• 2004

MCMB (Mesocarbon microbeads) is a kind of anode material for lithium-ion secondary battery. MCMB charge/discharge cycle stability is one of the important criterion at lithium-ion battery operation. In this study, the cycling stability of a lithium-ion secondary battery has been examined. MCMB was made by the direct solvent extraction method. After the MCMB was carbonized and graphitized, the measurement of charge/discharge capacity and efficiency were carried out. In the result, discharge capacity of MCMB in the initial cycle was above 290.0 mAh/g. After the second cycle, efficiency of charge/discharge MCMB was about 98%. These results were similar to the commercial MCMB product.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1999.11a
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• pp.29-39
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• 1999

Both conventional and PI3 implanters require dense sources for high productivity rate, and small sheath expansion in PI3 besides. The problem of the creation of large volume uniform plasma in PI3 facilities replaces that of beam forming in accelerators. Some aspects of ion extraction in both cases and Langmuir probe plasma diagnostics with be discussed. Plasma parameters of large volume multicusp dc hot cathode and inductively coupled RF plasma sources obtained with Langmuir probe and ion mass analyzer with be presented. Design features and performances of high current Freeman and ECR ion sources will be described.

• Proceedings of the Korean Vacuum Society Conference
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• 2005.08a
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• pp.161-161
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• 2005

• Resources Recycling
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• v.32 no.6
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• pp.90-90
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• 2023

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.58-61
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• 2012

The solvent extraction of platinum (IV) metal from hydrochloric acid media using 4-(4-ethoxybenzylideneamino)-5-methyl-4H-1,2,4-triazole-3-thiol (EBIMTT) in chloroform was studied as a function of several variables, such as reagent, acid and metal ion concentration, effect of various diluents, and diverse ions. The proposed method was further applied for the separation of platinum (IV) from binary mixtures, synthetic mixtures, alloys and commercially available samples.

• KSBB Journal
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• v.15 no.3
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• pp.293-298
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• 2000

${\beta}$-Glucan a kind of polysaccharide which is particularly abundant in Agaricus blazei is known as the bioactive materials especially anticancer agents. The process development of the isolation and the purification process of water soluble ${\beta}$-glucans from A. blazei was achieved. and the process operation variables were optimized. Crude polysaccharides (CR.PS) were obtained from A. blazei by hot water extraction filtration solvent precipitation dialysis and freeze drying. Neutral and acidic fraction of polysaccharides were separated from crude polysaccharides by ion chromatography and then high molecular weight and low molecular weight fraction were separated from neutral fraction by gel chromatography. Quantitative and qualitative analysis of each compounds were performed with FT-IR NMR spectroscopy. Based on these analysis the optimal conditions of temperatures operating time organic solvent volume for precipitation and dialysis time were determined.

• Analytical Science and Technology
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• v.11 no.6
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• pp.499-504
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• 1998

An analytical method for the simultaneous measurement of trace Cu, Sn, and Bi in sea water has been investigated by Inductively Coupled Plasma-Mass Spectrometry. Amberlite IRC-718 resin was used as a solid phase in solid-liquid extraction technique for the removal of matrix interferences such as Na, S, P, and other polyatomic ion species. Recoveries of 99.8% for Cu, 99.6% for Sn, and 97.9% for Bi were obtained for the standard spiked sample. The developed method was applied to analysis of trace metals in sea water.