• Macromolecular Research
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• v.8 no.4
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• pp.147-152
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• 2000

The activity of periodic acid as an initiator for the polymerization of acrylamide in aqueous medium was investigated. The rate of polymerization was found to be proportional to the monomer concentration to the 1.5th power in the range of 1.41-5.64 mol/L. The reaction order to the periodic acid concentration was 0.49, which indicated a bimolecular mechanism for the termination reaction in the range of 0.5-4.0$\times$10$\^$-2/ mol/L. Propagation rate increased with raising the temperature according to an Arrhenius expression resulting in the exhibition of an apparent activation energy of 87.8 kJ/mol in the temperature range of 60-80$\^{C}$. The addition of hydroquinone as a radical scavenger stopped the polymerization of acrylamide initiated by periodic acid. These results support that the polymerization proceeds via a radical chain mechanism .

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.1
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• pp.171-173
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• 2006

Trichomonicidal activity of thirty methanolic herbal extracts used in traditional medicine in Korea was evaluated. Trichomonas vaginalis was used as experimental model, and anti-Trichomonas activity was determined over cultures of the parasite in TYM Diamond medium. Six methanolic extracts such as Acanthopanacis Cortex, Agrimoniae Herba, Pulsatillae Radix, Sanguisorbae Radix, Sophorae Radix, and Torilidis Fructus showed more than 50% trichomonicidal activity at the concentration of 200 g/ml. These extracts were further fractionated into n-butanol soluble and aqueous phases. Except for Acanthopanacis Cortex, all of n-butanol soluble phases showed potent trichomonicidal activity, while none of aqueous phases exhibited trichomonicidal activity.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.210-218
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• 2018

Ethylenediaminetetraacetic acid (EDTA)-functionalized KIT-6 and KCC-1 mesoporous silicas were prepared via post-synthesis grafting and examined for their ability to promote the recovery of rare earth metal ions such as $Nd^{3+}$ from an aqueous medium. The obtained adsorption isotherms were fitted to the Langmuir model, which gave a maximum adsorption of $Nd^{3+}$ ions of 109.8 and 96.5 mg/g for KIT-6-EDTA and KCC-1-EDTA, respectively, at $25^{\circ}C$ and pH 6. The adsorption kinetic profile of KIT-6 was faster than KCC-1. KIT-6 was also proved to be more stable against desorption under acidic regeneration conditions.

• KSBB Journal
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• v.11 no.6
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• pp.726-732
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• 1996

Selective adsorption of plant metabolites from a polar dilute solution onto a polycarboxyl ester sorbent (XAD-7) was investigated. Experimental results demonstrated that neutral resins could selectively concentrate specific flavonoids from dilute aqueous mixtures. Adsorption was dependent on the pH of medium, dosage of the resins and medium composition. Especially the medium composition was a key factor for the selective adsorption and it was found that the selective adsorption was dependent on specific sorbent-sorbate-medium characteristics. Under the optimum condition, selectivity increased up to 85% and the yield of recovery was approached to 98%. It was also found that XAD-7 adsorbed flavonoids in the order of hydrophobicity.

• Korean Chemical Engineering Research
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• v.58 no.3
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• pp.466-473
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• 2020

Fabric current collector can be a promising electrode material for Capacitive Deionization (CDI) system that can achieve energy-efficient desalination of water. The one of the most attractive feature of the fabric current collector is its high tensile strength, which can be an alternative to the low mechanical strength of the graphite foil electrode. Another advantage is that the textile properties can easily make shapes by simple cutting, and the porosity and inter-fiber space which can assist facile flow of the aqueous medium. The fibers used in this study were made of woven structures using a spinning yarn using conductive LM fiber and carbon fiber, with tensile strength of 319 MPa, about 60 times stronger than graphite foil. The results were analyzed by measuring the salt removal efficiency by changing the viscosity of electrode slurry, adsorption voltage, flow rate of the aqueous medium, and concentration of the aqueous medium. Under the conditions of NaCl 200 mg/L, 20ml/min and adsorption voltage 1.5 V, salt removal efficiency of 43.9% in unit cells and 59.8% in modules stacked with 100 cells were shown, respectively. In unit cells, salt removal efficiency increases as the adsorption voltage increase to 1.3, 1.4 and 1.5 V. However, increasing to 1.6 and 1.7 V reduced salt removal efficiency. However, the 100-cell-stacked module showed a moderate increase in salt removal efficiency even at voltages above 1.5 V. The salt removal rate decreased when the flow rate of the feed was increased, and the salt removal rate decreased when the concentration of the feed was increased. This work shows that fabric current collector can be an alternative of a graphite foil.

• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.443-444
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• 2007

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1370-1373
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• 2006

The Cu-Ag nanoparticles have been synthesized in aqueous medium using a hydrazine reduction method. The assisted role of polymeric dispersant on synthesis of highly concentrated Cu-Ag nanoparticles was studied. The 30wt% of Cu-Ag nanoparticles with the range of 10 nm in diameter was prepared.

• Journal of Sericultural and Entomological Science
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• v.19 no.1
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• pp.33-36
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• 1977

Graft polymerization of vinyl monomers onto silk were carried out in aqueous medium using ceric salt as an initiator, and discussed about the mechanical properties of silk. The results obtained are summarized as follows: 1. Percent grafting is greatly enhanced by the increasing of the temperature. 2. Effect of percent grafting is in the order of methyl methacrylate, and vinyl acetate. 3. Strength is decreased in the high grafted silk, and elongation is increased in the low grafted silk.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2431-2435
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• 2013

A simple and efficient method for the synthesis of spiro[4H-pyran-oxindole] derivatives by means of three-component reactions between isatins, malononitrile or ethyl cyano-acetate, and 1,3-dicarbonyl compounds in the presence of catalytic amount of magnesium perchlorate in 50% aqueous ethanol medium has been described.

• Journal of Photoscience
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• v.9 no.3
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• pp.75-79
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• 2002

Solubility of carbon tetrachloride ($CCl_4$) in water increases appreciably in presence of $\beta$-cyclodextrin ($\beta$CD). $CCl_4$ is a very good quencher of 1-naphthol (1ROH) fluorescence. By studying the quenching of fluorescence of 1ROH included in $\beta$CD cavity, it was found that there is an increase in the availability of $CCl_4$ around $\beta$CD in the aqueous medium. This could help to rationalize the enhanced solubility of $CCl_4$.