• Journal of the Korean Chemical Society
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• v.39 no.2
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• pp.114-117
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• 1995

• Journal of the Korean Chemical Society
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• v.26 no.6
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• pp.427-429
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• 1982

• The Journal of Engineering Research
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• v.3 no.1
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• pp.189-197
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• 1998

Hyeroxyapatite(HAp) which has good biocompatibility was made by Wet Chemical Process. The surface of Ti-6Al-4V, coated with HAp by lon Beam Assisted Deposition (IBAD), was treated with 5ppm, 10ppm, 20ppm, and 100ppm of $AgNO_3$ solution. In this Ag impregnation process, $Ca^{2+}$ of HAp was substituted with $Ag^+$ of $AgNO_3$. In this study, the antimicrobial effect and biocompatibility of Ti-6Al-4V alloy which was coated with Ag-HAp were examined. The antimicrobial test was carried out with two kinds of bacteria(P. Aeruginosa, S. Epidermidis), which are highly infectious in a transplanting operation of implant materials. As a result of the test, it was observed that Ti-6Al-4V alloy which was treated by 20ppm of $AgNO_3$ solution has good biocompatibility. In order to observe the antimicrobial mechanism of $Ag^+$, E. coli which is the most common bacterium was treated by Ag-HAp. Then cell morphology of E. coli was observed by the transmission electron microscope(TEM). The destruction of cell wall and cytoplasm of E. coil were observed. A black spot appeared in the cytoplasm was analyzed by energy dispersive analysis X-ray (EDAX) and it showed a small amount of $Ag^+$. Thus, it was proved that $Ag^+$ destroys bacteria effectively and Ti-6Al-4V alloy which was impregnate with Ag ion show antimicrobial effect on infection bacteria.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.15-20
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• 2003

During operation process of SIES(Selective ion exchange system) at Kori Unit 2, it was impossible to remove radionuclides such as ion form and Ag-110m, etc., because activated carbon and ion exchange resin of this system are fouled easily by suspended solids and oils in liquid radwaste that was flowed in this system. In this study, an experiment to improve quality of water which was flowed in SIES was performed. and design data of Scale-up pretreatment process were secured. Also, each module design for Microfiltration and Nanofiltration unit of the pretreatment process for SIES was performed.

• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1832-1838
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• 2006

The present paper is focused on sorption concentration of silver (I) on some complex-forming ion exchangers in the initial thiocyanate form and subsequent determination of Ag(I) in the phase of anion exchanger AN-25 by diffuse reflectance spectroscopy. The sorption and kinetic characteristics of the sorbents were investigated. The apparent stability constants of thiocyanate silver complexes in the ion exchanger phase were calculated. The sorption-spectroscopic method is proposed for Ag(I) determination in aqueous solutions. The calibration curve is linear in the concentration range of 10-200 mg/L (sample volume is 10.0 mL) and the detection limit is 2 $\mu$g/mL. The presence of $Na^+,\;K^+,\;Mg^{2+}$ (macrocomponents) as well as of Ni (II), Co (II), Cu (II) do not hinder the determination of silver (I).

• Analytical Science and Technology
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• v.12 no.6
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• pp.521-527
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• 1999

In this study, capillary columns for ion chromatography were developed to analyze trace amount of ions in samples. When small I.D. capillary columns are used in ion chromatography, the typical flow rate of the mobile phase is $5{\sim}15{\mu}L/min$ and the typical column length is 50~150 mm. The capillary columns were made using RSL-300 fused silica capillary(I.D.: 0.53 mm, O.D.: 0.67 mm) and AG14 column resin(support : polystyrene-divinylbenzene, functional group : alkyl quaternary ammonium). The new conductivity cell and suppressor were also developed and made for capillary column ion chromatography. When several anions (fluoride, nitrite, nitrate, chlorate) were analyzed using these capillary columns, reproducible and good chromatograms were obtained.

• Journal of the Korean Ceramic Society
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• v.46 no.1
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• pp.41-46
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• 2009

The rheological properties of highly concentrated Ag nano sol depending on particle size were studied. The Ag nano sol was prepared by reducing the Ag ion in aqueous solution. The size of Ag nano particle was controlled by two steps of nucleation and growth, and the thickness of adsorption layer was varied by molecular weight of polyelectrolytes. The polyelectrolytes acted as not only ionic complex agent in ionic state and but also dispersant after formation of Ag nano sol. The effective volume was controlled by combination of varying the molecular weight of polyelectrolytes and the size Ag nano sol. The particle size and the viscosity of nano sol were characterized by particle size analyzer, HR-TEM and cone & plate viscometer. It was found that the 10 nm and 40 nm-sized Ag nano sols were prepared by controlling the nucleation and growth steps, respectively. Finally, we could prepare highly concentrated Ag nano sol over 50 wt%.

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1105-1109
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• 2014

While single strand DNAs have been widely used for the scaffold of brightly fluorescent silver nanoclusters (Ag NCs), double strand DNAs have not been as successful. Herein, we report a novel synthetic approach for bright Ag NCs using branched double strand DNAs as the scaffolds for synthesis. X-shaped DNA (X-DNA) and Y-shaped DNA (Y-DNA) effectively stabilized Ag NCs, and both X-DNA and Y-DNA resulted in brightly fluorescent Ag NCs. The concentration and molar ratio of silver and DNA were found important for the fluorescence efficiency. The brightest Ag NC with the photoluminescence quantum efficiency of 19.8% was obtained for the reaction condition of 10 ${\mu}M$ X-DNA, 70 ${\mu}M$ silver, and the reaction time of 48 h. The fluorescence lifetime was about 2 ns for the Ag NCs and was also slightly dependent on the synthetic condition. Addition of Cu ions at the Ag NC preparations resulted in the quenching of Ag NC fluorescence, which was different to the brightening cases of single strand DNA stabilized Ag NCs.

• Journal of the Korean Chemical Society
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• v.53 no.4
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• pp.476-480
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• 2009

• Journal of Powder Materials
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• v.8 no.3
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• pp.192-196
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• 2001

Ag doped Hydroxyapatite powder in nano-scale was successfully synthesized either by co-precipitation or by ion exchange route. The fabricated powder was successfully dispersed through freeze drying due to the prevention of secondary particles. The antimicrobial effects of nano-HAp against E.coli was superior to micron ones not only in its strength but also in duration.