• 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.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.814-816
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• 2005

In this paper, we describe how specially developed polymer capped, nano-particle silver inks can be used to print circuitry for applications like displays, RFID antennas and "disposable electronics". The requirements of printing on temperature sensitive flexible substrates (such as polymer films and papers) that require low temperature curing is also discussed.

• Journal of Environmental Science International
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• v.21 no.8
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• pp.901-907
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• 2012

The objective of this study was to evaluate bacteria removal ability of the metallic silver which was baked silver ion impregnated ceramic filter at heating condition. Silver leaking from baked ceramic filter was tested to sustain bacteria removal for a long time. Silver impregnated ceramic filter could remove E. coli completely at $10^{12}$ MPN/100ml to $10^{13}$ MPN/100ml of influent. However, ceramic filter without silver did not remove E. coli completely under the same condition. After baking, the silver impregnated ceramic filter almost didn't leak out the silver ion from filter. Photo of TEM (Transmission Electron Microscopy) showed that absorbed silver ions remained in ceramic filter after baking process and most of silver were less than 10 nm. According to the increase in the amount of silver in the ceramic filter, removal efficiencies of E. coli were increased but turbidity removal was decreased. It can be accounted that increased removal efficiency of E. coli was from disinfection of silver that is in the ceramic filter. Simulated concentrations of bacteria agree well with the observed experimental effluent concentration data. Moreover, first-order decay coefficients increased to 0.0034/min after silver was added in the ceramic filter. Increase of first-order decay coefficient proves that silver-added ceramic filter can remove bacteria easily.

• Advances in nano research
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• v.2 no.2
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• pp.111-119
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• 2014

The chemical synthesis of anisotropic defective polyaniline/Ag composite (PANI/Ag) is explored using silver nitrate ($AgNO_3$) as the precursor material. This study provides a simple method for the formation of PANI/Ag nanocomposites at two different aniline concentrations $5{\mu}l$ (PANC5) and $10{\mu}l$ (PANC10). The composite PANC5 exhibits UV-Visible absorption peaks at 436 nm and 670 nm whereas, PANC10 exhibits absorption peaks at 446 nm and 697 nm. This shift is caused by the strong interaction between polyaniline and silver. The characterized FTIR peaks observed at around $3410cm^{-1}$ (PANC5) and $3420cm^{-1}$ (PANC10) was due to the N-H stretching vibrations. The appearance of a broad band instead of a sharp peak can be attributed due to the presence of a high concentration of N-H groups in the nanocomposite. The TEM images show that the sample contains defective spherical, truncated triangular and rod shaped particles. The results showed that the PANI/Ag nanocomposites are composed of nano-sized particles of 43-53 nm that contain Ag domains of 33-37 nm with polymer thickness 5.7-11.2 nm at two different aniline concentrations.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.8
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• pp.531-538
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• 2015

This study examined the size and shape of the nano-silver particle through the analysis of electrical resistance when synthesizing nano-sized silver by using the chemical liquid reduction. Changes in particle behaviors formed according to the changes in electronic characteristics by electric resistance in each time period in the beginning of reduction reaction in a course of synthesizing the nano-silver particle formation were studied. In addition, analysis was conducted on particle behaviors according to the changes in concentration of $AgNO_3$ and in temperature at the time of reduction and nucleation and growth course when synthesizing the particles based on the particle behaviors were also examined. As the concentration of $AgNO_3$ increased, the same amount of resistance of approximately $5{\Omega}$ was increased in terms of initial electronic resistance. Furthermore, according to the result of formation of nuclear growth graph and estimation of slope based on estimated resistance, slops of $6.25{\times}10^{-3}$, $2.89{\times}10^{-3}$, and $1.85{\times}10^{-3}$ were derived from the concentrations of 0.01 M, 0.05 M, and 0.1 M, respectively. As the concentration of $AgNO_3$ increased, the more it was dominantly influenced by the nuclear growth areas in the initial phase of reduction leading to increase the size and cohesion of particles. At the time of reduction of nano-silver particle, the increases of initial resistance were $4{\Omega}$, $4.2{\Omega}$, $5{\Omega}$, and $5.3{\Omega}$, respectively as the temperature increased. As the temperature was increased into $23^{\circ}C$, $40^{\circ}C$, $60^{\circ}C$, and $80^{\circ}C$, slopes were formed as $4.54{\times}10^{-3}$, $4.65{\times}10^{-3}$, $5.13{\times}10^{-3}$, and $5.42{\times}10^{-3}$ respectively. As the temperature increased, the particles became minute due to the increase of nuclear growth area in the particle in initial period of reduction.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.7 s.144
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• pp.918-925
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• 2005

The following are the results from the infrared body temperature image test to verify the changes in facial temperature according to call duration with a cellular phone. As for the body temperatures, it appears to be the mean value at the upper central point of phone's battery among 7 different points that are measured, and to be the highest at srernocleido-mastoid and scapular trapezius muscle triangle zone$(34.25^{\circ}C\; and\;34.05^{\circ}C\;each)$. The changes of body temperature according to the time duration shows that the body temperature rises according to the length of phone use because of the heat emitted from the battery. As for the temperature changes according to blocking materials, the one without processing appears to be higher in the mean temperature compared to the others that are processed, NSS(Nano Silver Silk) and NSG(Nano Silver Silk Gold) appear to be the lowest in the temperature to show the best blocking property. As for the temperature changes according to measuring points, it appears to be the highest at P4, P5 with all materials, and one with NSG to be the lowest at Pl, P2, P3, and one with NSS to be the lowest at P3, P4, P5, P6, which is due to the thermal conduction of Au and Ag. And the mean temperature at each point appears to be different according to the materials. Therefore, the study conducted with human participants requires a proper particle size of it which would not penetrate cellular tissues and a proper binder and binding treatment for it, to prevent the physical fatigues and the potential diseases. However, it is highly required for back-up researches to verify various aspects in applying nano silver to textile products.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.511-511
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• 2007

Low-emissivity (low-e) coatings with visible transparency have attracted increased interest m reducing heat radiation loss through window panes from ecological and sustainable aspects. $TiO_2$-silver transparent thin films for low-e have good properties for UV and IR blocking as well as photocatalyst compared to that with commercial UV blocking films such as fluorine doped oxide (FTO), antimony doped tin oxide (ATO), etc. In this study, transparent $TiO_2$-silver thin films were prepared by successive ink-jet printing of commercial nano silver and $TiO_2$ sol. The $TiO_2$ sol, as ink for ink-jet printing, were synthesized by hydrothermal process in the autoclave externally pressurized with $N_2$ gas of 200 bar at $120^{\circ}C$ for 10 hrs. The synthesized $TiO_2$ sols were all formed with brookite phase and their particle size was several to 30 nm. At first nano sized silver sol was coated on glass substrate, after that $TiO_2$ sol was coated by ink-jet printing. With increasing coating thickness of $TiO_2$-silver multilayer by repeated ink-jet coating, the absorbance of UV region (under 400nm) and IR region (over 700nm) also increase reasonably, compared to that with commercial UV blocking films.

• Journal of the Korean Vacuum Society
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• v.21 no.1
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• pp.12-16
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• 2012

Although silver is used for T-OLED (Top emitting organic Light-Emitting Diode) as reflective anode, it is not an ideal material due to its low work function. Thus, we study the effect of annealing and atmospheric pressure plasma treatment on Ag film that increases its work function by forming the thin silver oxide layer on its surface. In this study, we deposited silver on glass substrate using RF sputtering. Then we treated the Ag samples annealing at $300^{\circ}C$ for 30 minutes in atmosphere or treating the atmospheric plasma treatment for 30, 60, 90, 120s, respectively. We measured the change of the mechanical properties and the potential value of surface with each one at a different treatment type and time. We used nano-indenter system and KPFM (Kelvin Probe Force Microscopy). KPFM method can be measured the change of surface potential. The nanoindenter results showed that the plasma treatment samples for 30s, 120s had very low elastic modulus, hardness and Weibull modulus. However, annealed sample and plasma treated samples for 60s and 90s had better mechanical properties. Therefore, plasma treatment increases the uniformity thin film and the surface potential that is very effective for the performace of T-OLED.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1510-1515
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• 2004

The effects of additive ions on the generation of metallic nanoparticles were evaluated using a corona induced supersonic nozzle. Applying the corona discharge to the nanoparticle generator, a tungsten needle and the supersonic nozzle are used as an anode electrode and a cathode electrode respectively. The corona ions act as nuclei for the silver vapor condensation. The ion density was controlled precisely as varying the applied voltage between electrode and nozzle. The mean diameter of the silver particle decreases as the ion density increases. However, the number concentration of the silver particle tended to increase with the ion density. The size distribution is more uniform as the ion density increases.