• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.658-665
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• 2006

The removal characteristics of silver ion from waste photographic solution have been investigated by recovering silver electrochemically. Cyclic voltammetry for synthetic and actual wastewater which containing silver ion was investigated to understand its electrochemical behavior. For both synthetic and actual wastewater, the recovery of silver according to the electrowinning time was observed to be increased as the applied potential was raised. In addition, the applicable potential for the electrowinning of silver was found to be lower for synthetic wastewater compared with actual wastewater. As the temperature was increased, more silver was recovered for both wastewater, which indicated the electrowinning reaction was endothermic. The electrowinned silver was refined electrochemically to increase its purity and the variation of the purity of silver was examined according to the electrorefining potential.

• Fashion & Textile Research Journal
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• v.7 no.3
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• pp.333-338
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• 2005

We examined the antimicrobial effects of the cotton fabrics which were laundered at different conditions and treated with a colloidal silver solution using Staphylococcus aureus. Colloidal silver solution was made from commercial colloidal silver generator by electrolysis. The fabric which was innoculated and washed with water before drying had no more Staphylococcus aureus, but which was innoculated and dried before washing with detergent solution had lower reduction rate. The fabric washed with oxygen bleach did not have an antimicrobial effect, but rinsed with 0.07% fabric softener showed antimicrobial properties. The fabric rinsed with 0.7ppm colloidal silver solution had better antimicrobial effects. As the treating concentration of silver solution increased, the antimicrobial property of the fabric was increased. The fabric treated with 5% silver solution sustained reflectance and whiteness of untreated fabric. The colloidal silver treated fabric lost antimicrobial property after washing because nano-sized silver particles were located on uneven fiber surface without chemical bonding forces.

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.175-176
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• 2012

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.173-174
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• 2012

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.171-172
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• 2012

• 한국약용작물학회:학술대회논문집
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• 2012.05a
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• pp.145-146
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• 2012

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.2 s.245
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• pp.170-176
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• 2006

A spark discharge aerosol generator using air as a carrier gas has successfully been applied to silver nanoparticle production. The spark discharge between two silver electrodes, which was periodically obtained by discharging the capacitor, produced sufficient high temperatures to evaporate a small fraction of the silver electrodes. The silver vapor was subsequently supersaturated by rapid cooling and condensed to silver nanoparticles by nucleation and condensation. The morphology of the generated particles observed by transmission electron microscope was spherical. The element composition of the nanoparticles was silver, which was determined by energy dispersive X-ray spectroscopy. The crystal phase of the particles spark-generated under air atmosphere was composed of silver and silver oxides phase, which was determined by Xray diffraction analysis. While the nanoparticles generated under nitrogen atmosphere had only silver phase. This XRD data indicates that some fraction of the evaporated silver vapor could be oxidized in air atmosphere by the reaction with oxygen. A stable operation of the spark discharge generator has been achieved. The size and concentration of the particles can be easily controlled by altering the repetition frequency, capacitance, gap distance and flow rate of the spark discharge system.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.553-558
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• 2011

Copolymeric silver nanocomposite hydrogels were synthesized by using acryloyl phenylalanine (APA), N'-isopropylacrylamide (NIPAM) and crosslinked by N,N-methylene bisacrylamide (MBA) via radical redox polymerization. Present study allows entrapping silver nanoparticles into hydrogel networks. UV-visible spectroscopy and X-ray diffraction (XRD) studies confirmed the formation of silver nanoparticles in hydrogel matrix. 11% of weight loss difference between hydrogel and silver nanocomposite hydrogel is clearly indicates the formation and silver nanoparticles by thermo-gravimetrical analysis. The order of swelling capacity values of hydrogels and silver nanocmposite hydrogels were found to be in the order of placebo copolymeric hydrogel >Ag-copolymeric silver nanocomposite hydrogels. The particle size of silver nanoparticles was analysed and are in the range of 5 - 10 nm which has been confirmed by transmission electron microscopy (TEM) as well as particle size analysis. The silver nanocomposite hydrogel has shown very good antibacterial activity on gram-positive and gram-negative bacteriocides.

• Macromolecular Research
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• v.17 no.2
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• pp.104-109
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• 2009

Solid-state facilitated, olefin transport membranes were prepared by complexation of poly(styrene-b-iso-prene-b-styrene) (SIS) block copolymer and silver salt. Facilitated olefin transport was not observed up to a silver mole fraction of 0.14, representing a threshold concentration, above which transport increased almost linearly with increasing silver salt concentration. This was because firstly the silver ions were selectively coordinated with the C=C bonds of PI blocks up to a silver mole fraction of 0.20, and secondly the coordinative interaction of the silver ions with the aliphatic C=C bond was stronger than that with the aromatic C=C bond, as confirmed by FT-Raman spectroscopy. Small angle X-ray scattering (SAXS) analysis showed that the cylindrical morphology of the neat SIS block copolymer was changed to a disordered structure at low silver concentrations ($0.01{\sim}0.02$). However, at intermediate silver concentrations ($0.15{\sim}0.20$), disordered-ordered structural changes occurred and finally returned to a disordered structure again at higher silver concentrations (>0.33). These results demonstrated that the facilitated olefin transport of SIS/silver salt complex membrancs was significantly affected by their coordinative interactions and nano-structural morphology.

• Macromolecular Research
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• v.16 no.7
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• pp.626-630
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• 2008

Poly(vinyl pyrrolidone) was used successfully to control the size and distribution of silver nanoparticles generated on inorganic silica nanofibers. The inorganic nanofibers were electro spun using sol-gel chemistry of silicates, and the diameter of the prepared nanofibers was unaffected by adding up to 7% of poly(vinyl pyrrolidone). The silver ions, in the form of silver nitrate, were introduced into the silica nanofibers and reduced to metallic silver by ultraviolet irradiation with a subsequent thermal treatment. The size of the generated silver particles was decreased dramatically by adding poly(vinyl pyrrolidone). The size of the silver nanoparticles was 73 nm when no poly(vinyl pyrrolidone) was added but 23 nm with the addition of only 1% of poly(vinyl pyrrolidone). The extent of reduction could be checked by determining the concentration of silver ions leached into water from the silica nanofibers. After thermal treatment of the silica nanofibers, more than 99% of the silver remained in the nanofibers, indicating almost complete reduction of the silver ions to silver metal.