• Journal of the Korean Crystal Growth and Crystal Technology
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• v.2 no.1
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• pp.76-85
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• 1992

${\beta}-$Ag_2S$(high temperature phase) was grown by solid/vapour reaction growth based on solid -state electrochemisty. In S/V growth, one of the reactants, silver ion, is supplied to the growth surface through the solid $Ag_2S$ from one side and the other reactants, surfur, is transported in the phase of vapour from the other side. With the sufficient supply of S vapour, the growth rate increased as increasing $T_d$(decomposition temperature of $Ag_2S$) and ${\Delta}T$ between $T_d$ and $T_g$(temperature of growth surface). At low S vapour pressure, growth rate decreased with decreased vapour pressure and ${\beta}-$Ag_2S$ was grown in the form of whisker, when Ag+ion is sufficiently supplied. The measured values of electronic conductivity of ${\beta}-$Ag_2S$ showed that electronic conductivity of the poly crystal was larger than that of single crystal.

• Korean Journal Plant Pathology
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• v.1 no.1
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• pp.72-78
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• 1985

The effects of temperature. pH, carbon and nitrogen sources on the growth of Rhizoctonia solani were studied by using five hyphal anastomosis groups(four cultural types, 7 isolates) of the fungus. The ranges of optimum temperature were $20^{\circ}C$ in the AG 2-1, AG 2-2 and AG 4, and $25^{\circ}C$ in the AG 1-IA, AG 1-IB, AG 3, AG 5. The optimum pH for the mycelial growth was 6-7 in the fungus. Glucose in the AG 1-lA, AG 1-IB, AG 2-2, AG 3 and AG 5, sucrose in the AG 2-1 and fructose in the AG 4 were the most effective for the mycelial growth, but glycerine, cellulose and lactose were not effectively utilized as nutrients. $Ca(NO_3)_2$ in the AG 1-IA, AG 1-IB and AG 4, asparagine in the AG 2-1, $KNO_3$ in the AG 2-2 and $NaNO_3$ in the AG 5 were the best nitrogen sources for the mycelial growth, but $NH_4NO_3$ was not easily utilized by the fungus. Nitrate and organic nitrogens for the fungal growth were utilized better than ammonium nitrogen.

• ETRI Journal
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• v.19 no.2
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• pp.71-81
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• 1997

We report on the room-temperature-growth of highly uniform and ultrathin Ag films on Sb-terminated Si(111) surfaces, as evidenced from a scanning tunneling microscopy (STM) study in an UHV system. With predeposition of one monolayer (ML) of Sb, uniform growth of Ag islands was observed at room temperature. The Sb layer suppresses the surface diffusion of Ag atoms on Si surface and increases the Ag island density, and then the increased island density is believed to cause coalescence of Ag islands before the beginning of multilayer growth in higher coverages, resulting in the growth of atomically flat and uniform islands on the Sb surfactant layer.

• Biomedical Science Letters
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• v.24 no.1
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• pp.30-34
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• 2018

Silver (Ag) has been widely used in commercial products and medical fields since ancient times because of its antibacterial effect. It is harmless and non-toxic to the human body. For this reason, recent research has actively evaluated antimicrobial activity using silver (Ag). In this study, we investigated the inhibitory effect of a silver-based compound, silver phosphate ($Ag_3PO_4$) on the growth of Staphylococcus aureus and the activation of human immunity. First, the inhibitory effect of $Ag_3PO_4$ on the growth of Staphylococcus aureus was confirmed by a growth curve and a colonyounting method. As a result, the growth inhibitory effect increased as the concentration of $Ag_3PO_4$ increased. Specifically, treatment with $5{\mu}g/mL$ of $Ag_3PO_4$ resulted in no bacteria growth, and the colony-counting method showed a remarkable inhibition. In addition, the expression of cytokine IL-8 by $Ag_3PO_4$ was examined to investigate the cellular immune system activation by $Ag_3PO_4$. After pretreatment of Staphylococcus aureus for 1 hour with $50{\mu}g/mL$ $Ag_3PO_4$, an increased IL-8 mRNA expression resulted. In cells treated with $Ag_3PO_4$, we found that the expression of IL-8 was enhanced in a time-dependent fashion compared to non-treated cells. These results indicate that $Ag_3PO_4$ induces antimicrobial activity against Staphylococcus aureus and activates human immunity. These results are expected to contribute to the future study of the mechanism of silver (Ag) and silver-based compounds in relation to antibacterial activity.

• Korean Journal of Materials Research
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• v.16 no.4
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• pp.257-263
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• 2006

We have investigated the effect of silver added to Cu films on the microstructure evolution, resistivity, surface morphology, stress relaxation temperature, and adhesion properties of Cu(Ag) alloy thin films deposited on Mo glue layer upon annealing. In addition, pure Cu films deposited on Mo has been annealed and compared. The results show that the silver in Cu(Ag) thin films control the grain growth through the coarsening of its precipitates upon annealing at $300^{\circ}C{\sim}600^{\circ}C$ and the grain growth of Cu reveals the activation energy of 0.22 eV, approximately one third of activation energy for diffusion of Ag dopant along the grain boundaries in Cu matrix (0.75 eV). This indicates that the grain growth can be controlled by Ag diffusion along the grain boundaries. In addition, the grain growth can be a major contributor to the decreased resistivity of Cu(Ag) alloy thin films at the temperature of $300^{\circ}C{\sim}500^{\circ}C$, and decreases the resistivity of Cu(Ag) thin films to $1.96{\mu}{\Omega}-cm$ after annealing at $600^{\circ}C$. Furthermore, the addition of Ag increases the stress relaxation temperature of Cu(Ag) thin films, and thus leading to the enhanced resistance to the void formation, which starts at $300^{\circ}C$ in the pure Cu thin films. Moreover, Cu(Ag) thin films shows the increased adhesion properties, possibly resulting from the Ag segregating to the interface. Consequently, the Cu(Ag) thin films can be used as a metallization of advanced TFT-LCDs.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.204.2-204.2
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• 2014

Among various metal oxides, ZrO2 is of particular interests and has received widespread attention thanks to its ideal mechanical and chemical stability. As a cheap metal, Ag nanoparticles are also widely used as catalysts in ethylene epoxidation and methanol oxidation. However, the nature of Ag-ZrO2 interfaces is still unknown. In this work, the growth, interfacial interaction and thermal stability of Ag nanoparticles on ZrO2(111) film surfaces were studied by low-energy electron diffraction (LEED), synchrotron radiation photoemission spectroscopy (SRPES), and X-ray photoelectron spectroscopy (XPS). The ZrO2(111) films were epitaxially grown on Pt(111). Three-dimensional (3D) growth model of Ag on the ZrO2(111) surface at 300 K was observed with a density of ${\sim}2.0{\times}1012particles/cm2$. The binding energy of Ag 3d shifts to low BE from very low to high Ag coverages by 0.5 eV. The Auger parameters shows the primary contribution to the Ag core level BE shift is final state effect, indicating a very weak interaction between Ag clusters and ZrO2(111) film. Thermal stability experiments demonstrate that Ag particles underwent serious sintering before they desorb from the zirconia film surface. In addition, large Ag particles have stronger ability of inhibiting sintering.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2003.11a
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• pp.133-137
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• 2003

The effect of Bi additions to the eutectic Sn-3.5Ag solder alloy on the growth kinetics of the intermetallic compound (IMC) layers during solid-state aging of Sn-Ag-Bi/Cu solder joints has been Investigated. The Bi additions enhanced the growth rate of the total IMC layer comprising of $Cu_6Sn_5$ and $Cu_3Sn$ sublayers. This enhanced IMC growth rate was primarily due to the rapid increase In the growth rate of $Cu_6Sn_5$ sublayer. The growth rate of $Cu_3Sn$ sublayers was little influenced and appeared to be retarded by the Bi additions. The observed growth behavior of $Cu_6Sn_5$ and $Cu_3Sn$ sublayers could be understood if the interfacial reaction barrier at the $Cu_6Sn_5/solder$ interface were reduced by the segregation of Bi at the interface.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.1
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• pp.63-70
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• 1994

Single crystals of the superionic conductor ${\beta}-Ag_3SI$ were prepared by thermal treatmentr from the reactant mixture of AgI and $Ag_2S$. The growing single crystals were made to spherical shape of $200{mu}m$ in diameter. The detailed structures analyses revealed that $Ag^+$ in ${\beta}-Ag_3SI$ distribute on 12h site of 4-coordination inpreference to 3c site of 6-coordination. The effective one-particle potential (o.p.p.). of $Ag^+$ along [110] direction was evaluated from the probability density function(p.d.f.) Activation energy calculated from the o.p.p. curve has been found to be 0.012 eV for the diffusion of $Ag^+$ on (001) plane in the ${\beta}-Ag_3SI$ structure.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.10a
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• pp.99-103
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• 1997

활성탄의 특성을 이용하여 상업적으로 문제시되고 있는 수질 및 공기 정화용 항균성 Ag-활성탄을 제조하여 흡착특성, 표면구조 및 박테리아 저항성에 대하여 조사하였다. 높은 비표면적을 가진 활성탄에 대하여 AgNO$_3$를 사용하여 Ag-활성탄을 제조하였다. 0.1에서 1.0까지의 AgNO$_3$ 몰농도에 침적된 Ag-활성탄의 비표면적 값은 874-1475 $m^2$/g의 범위에 분포하고 있었으며, AgNO$_3$몰농도가 증가함에 따라 비표면적이 작아지는 경향을 나타내어 흡착된 Ag가 원료 활성탄의 표면구조에 영향을 주었다. Ag는 활성탄 표면의 기공 주위에 고르게 분포되었으며 활성탄의 표면에 물리적 흡착에 의해 존재하는 것으로 나타났다. 항균실험을 위하여 박테리아로서 대장균의 일종인 Escherichia coli를 사용하였으며, 흡착된 Ag의 양이 증가됨에 따라 활성의 범위가 증가되었고, Ag가 흡착되지 않은 활성탄의 경우에 있어서는 활성을 전혀 나타내지 않았다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.1026-1029
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• 2001

Zinc films have been deposited onto various buffer layers, Al, Al-Cu, Ag and Ag-Al, by vacuum evaporation method in order to investigate the film microstructure and its consequence on the film growth. Zn films were grown onto Al buffer layers with faster rates than on Ag buffer layers, because of the presence of preferred growth orientation. Especially, in the Zn film formation on the Ag layers, intermetallic compounds AgZn was formed to cause the different growth orientation from Zn film obtained on the Al layers.