• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1594-1597
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• 2008

Carbon nanotube (CNT) cathodes were fabricated using nano-sized silver powders as a bonding material. The effects of powder size on the field emission properties for the CNT cathode were investigated The better emission properties of CNT cathodes using smaller particles are due to a low sintering temperature of the bonding materials.

• Korean Journal of Materials Research
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• v.29 no.1
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• pp.37-42
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• 2019

This study investigates Ag coated $Cu_2O$ nanoparticles that are produced with a changing molar ratio of Ag and $Cu_2O$. The results of XRD analysis reveal that each nanoparticle has a diffraction pattern peculiar to Ag and $Cu_2O$ determination, and SEM image analysis confirms that Ag is partially coated on the surface of $Cu_2O$ nanoparticles. The conductive paste with Ag coated $Cu_2O$ nanoparticles approaches the specific resistance of $6.4{\Omega}{\cdot}cm$ for silver paste(SP) as $(Ag)/(Cu_2O)$ the molar ratio increases. The paste(containing 70 % content and average a 100 nm particle size for the silver nanoparticles) for commercial use for mounting with a fine line width of $100{\mu}m$ or less has a surface resistance of 5 to $20{\mu}{\Omega}{\cdot}cm$, while in this research an Ag coated $Cu_2O$ paste has a larger surface resistance, which is disadvantageous. Its performance deteriorates as a material required for application of a fine line width electrode for a touch panel. A touch panel module that utilizes a nano imprinting technique of $10{\mu}m$ or less is expected to be used as an electrode material for electric and electronic parts where large precision(mounting with fine line width) is not required.

• Proceedings of the SAREK Conference
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• 2003.07a
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• pp.132-132
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• 2003

• Journal of Korean Society of Environmental Engineers
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• v.32 no.10
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• pp.936-941
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• 2010

This study was conducted to investigate formaldehyde removals by silver nano-particles attached on the surface of granular activated carbon (Ag-AC) and to compare the results to those obtained with ordinary activated carbon (AC). The BET analysis showed that the overall surface area and the fraction of micropores (less than $20{\AA}$ diameter) of the Ag-AC were significantly decreased because the silver particles blocked the small pores on the surface of the Ag-AC. The formaldehyde removal capacity of the Ag-AC determined using the Freundlich isotherm was higher than that of AC. Despite the decreased BET surface area and micropore volume, the Ag-AC had the increased removal capacity for formaldehyde, presumably due to catalytic oxidation by silver nano-particles. In contrast, the adsorption intensity of the Ag-AC, estimated by 1/n in the Freundlich isotherm equation, was similar to that of the ordinary AC, indicating that the surface modification using silver nano-particles did not affect the adsorption characteristics of AC. In a column experiment, the Ag-AC also showed a longer breakthrough time than that of the AC. Simulation results using the homogeneous surface diffusion model (HSDM) were well fitted to the breakthrough curve of formaldehyde for the ordinary AC, but the predictions showed substantial deviations from the experimental data for the Ag-AC. The discrepancy was due to the catalytic oxidation of silver nano-particles that was not incorporated in the HSDM. Consequently, a new numerical model that takes the catalytic oxidation into accounts needs to be developed to predict the combined oxidation and adsorption process more accurately.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.550-550
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• 2007

Inkjet printed silver films were fabricated using nano particles with the size of ~ 20 nm. We can obtain very good conducting silver films with the resistivity of $7.3\;{\mu}{\Omega}{\cdot}cm$ even though they were sintered at the very low temperature of $200^{\circ}C$. The electrical and mechanical properties of inkjet printed silver lines were measured with the sintering time and analyzed with the micro-structural development. The measured resistivity of inkjet printed Ag films were $57.4\;{\sim}\;7.3\;{\mu}{\Omega}{\cdot}cm$. And their hardness and Young's modulus were 0.98 ~ 1.72 GPa and 32 ~ 71 GPa, respectively.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.385-390
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• 2005

In this study, nano sized colloidal Ag was made by using a seed sol method. Colloidal Ag solution was spouted on the surface of the inorganic pigment using the hybridizer system and spray nozzle. Then, the surface of the inorganic pigment was modified by $TiO_2$ to obtain the antibacterial ability. In the manufacturing process of nano sized colloidal Ag, it was confirmed that the size of particles increased by addition of $AgNO_3$ and increased the reaction time. The antibacterial measurement of the inorganic pigment showed that the growth of fungus decreased as the reaction time was increased. After the antibacterial ability appeared, in 5~7 h of the antibacterial inoculation experiment, it was measured that the antibacterial activity was excellent at a fixed time frame. The photodecomposition of benzene using $TiO_2$ as the photocatalyst showed 60~70% efficiency in about 80 min. reaction time. It was shown that more than 90% of this efficiency was achieved in the reaction time of about 30 min.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.11a
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• pp.97-99
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• 2002

유리내부에 수십나노크기의 Ag 금속입자를 생성시키기 위한 연구를 진행하였다. 본 연구에서는 규산염계 유리에 Ag와 Ce을 첨가하여 환원분위기에서 유리를 제조함으로서 Ce$^{3+}$ 를 유리내에 생성시킬 수 있었으며, 또한 레이저조사(irradiation)를 통하여 Ag+이온의 금속입자 환원을 도울 수 있었다. 또한 레이저 조사시간에 따른 금속입자의 변화를 관찰하고자 하였으며, 이와 같은 과정으로 생성된 금속입자함유 유리를 열처리함으로서 나타나는 열적특성을 평가하여 금속입자가 결정화과정에 미치는 영향을 평가하고자 하였다. 유리내에 존재하는 나노금속입자를 투과전자현미경 (TEM)을 통하여 확인하였으며, 시차주사열량분석법(DSC)을 통해 유리의 결정화거동을 평가하였다. 또한 Photo Luminescence 측정을 통한 유리내부의 Ce이온의 전자상태를 관찰하였다.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.417-421
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• 2006

In this study, colloidal Ag solution was spouted on the surface of the inorganic pigment using the hybridizer system and the spray nozzle. Then, the surface of the inorganic pigment was modified by titanium dioxide in order to possess antibacterial ability. Nano-sized colloidal Ag was made by using a seed sol method in this study. It was confirmed that the size of particle per unit weight becomes enlarged, as the addition of $AgNO_{3}$ increased, and as the time of reaction increased, in the manufacturing process of nano-sized colloidal Ag. The antibacterial measurement of the inorganic pigment showed that the growth of fungus was reduced as the reaction time increased. It was measured that the antibacterial activity was excellent at fixed time frame, after the antibacterial ability appeared in $5{\sim}7$ hours of the antibacterial inoculation experiment. The experiment of titanium dioxide's Photocatalyst effect showed $60{\sim}70%$ efficiency in about 80 minute reaction time of the dissolution results regarding measurements of benzene. It was shown that more than 90% of the dissolution efficiency was achieved in the reaction time of about 30 minute.

• Applied Chemistry for Engineering
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• v.18 no.4
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• pp.396-399
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• 2007

In present work, the anti-bacterial effect of silver/activated carbon (Ag/C) composites prepared by the ${\gamma}$-irradiation of $AgNO_3$ solution on Escherichia coli (E. coli) has been studied. Characteristics of the Ag/C composites were identified by scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic absorption spectroscopy (AAS). The inhibitory concentration of E. coli was found to be 0.387 ppm and the sterilizing concentration for the tested organism was 1.017 ppm. These results support the evidence that Ag/C composites have strong antibacterial activity to E. coli.

• Advances in nano research
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• v.11 no.6
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• pp.657-665
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• 2021

The present work aimed to explore green approach via aqueous leaves extract of Murraya koenigii (ALEMk) for the synthesis of silver nanoparticles (AgNPsMk) in single step. The synthesis process was visualized with a color change and monitored by employing UV/Visible spectroscopy and a clear peak attained at 420 nm confirming the synthesis of AgNPsMk. The possible functional groups present in the extract which participated in the synthesis of AgNPsMk were identified with the help of FTIR spectroscopy. Further characterization using TEM images revealed the spherical shape of AgNPsMk with average particle size of 20 nm displaying well dispersion throughout the solution. Pronounced antioxidant activities of AgNPsMk at increased concentrations observed which evidencing strong radical scavenging ability. Moreover, AgNPsMk exhibited strong antibacterial behavior when tested against bacterial strains of Escherichia coli and Bacillus subtilis. Moving ahead, in vitro cytotoxicity work revealed potent cell viability loss appearing in AU565 and HeLa cancer cell lines on exposure to AgNPsMk at increased concentration. Finally, in vivo assessment carried out inside male Wistar rats indicated non toxic effect on examined liver tissues besides biochemical analysis including bilirubin, alkaline phosphtase (ALP) and serum glutamate pyruvate transaminase (SGPT) which found within the normal range when compared with control. The prior research work profoundly apprises the potential of green synthesized AgNPsMk to play a significant role in biomedical applications and formulations.