• Journal of Korean Society of Environmental Engineers
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• v.27 no.5
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• pp.549-554
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• 2005

Porous ceramic beads that had skeleton structure were impregnated with Ag from silver nitrate solution. Ag-impregnated porous ceramic beads were performed to evaluate the antibacterial properties on Escherichia coli and Staphylococcus aureus, also, compared with commercial silver-activated carbon on antibacterial activity. As concentration of silver nitrate solution increased, deposited-Ag contents of outer and inner surface of beads were increased. The size of silver particles supported on porous ceramic bead were range of $0.5{\sim}2.0\;{\mu}m$. The observed effects of the prepared Ag-impregnated beads on antibacterial activity are as follows : i) Antibacterial activity should be directly proportional to silver nitrate solution and reaction time. ii) The antibacterial activity against Escherichia coli was better than that against Staphylococcus aureus.

• Restorative Dentistry and Endodontics
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• v.18 no.2
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• pp.469-481
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• 1993

The purpose of this study was to achieve the reduction of the galvanic current between the dental amalgam alloy and gold alloy. In order to measure the galvanic current between these two metals a prep in the size of $4{\times}13mm$ which was filled with amalgam and another prep of $4{\times}2mm$ was filled with gold alloy was made in the acrylic resin. These two preps were then connected to a 2mm diameter copper wire. Using an ammeter to measure the galvanic current, six different kinds of amalgam and gold alloy were immersed in saline solution with approximately 10mm distance between the two alloys. Chemical agents that are thought to reduce the galvanic current such as hydrazine. silver nitrate, potassium chromate, and bonding agents such as Scotch bond 2(3M) and All bond 2(Bisco) were applied to the alloy surface. Cathodic inhibitor such as hydrazine was applied to gold alloy where as anodic inhibitor such as silver nitrate and potassium chromate were applied to amalgam. Both bonding agents, Scotch bond 2(3M) and All bond 2 (Bisco), were applied to amalgam. The following results were obtained when the currency on the coated alloy surface was compared to the uncoated surface. 1. The galvanic currency went down as the time elapsed and after 30 minutes no change was detected. 2. Initial currency was higher in low copper amalgam compared to high copper amalgam. Intitial currency was the highest in low copper lathe-cut amalgam. 3. Group of gold coated with hydrazine had the most reduction in galvanic currency. 4. Group of amalgam coated with silver nitrate or potassium chromate also showed significant reduction in galvanic currency. 5. The bonding agents also helped reduce galvanic currency. 6. Of all the agents used to reduce galvanic currency, silver nitrate showed the best result.

• Food Science and Preservation
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• v.6 no.3
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• pp.286-291
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• 1999

This study was carried out to determine the effect of dose and timing of gamma irradiation and post-irradiation treatment with some preservatives of cut flowers on their longevity of rose and chrysanthemum. Cut roses which were soaked in 2% sugar solution persist to 0.75 kGy irradiation treatments. In post-treatments with some preservative solutions, the mixture group of 2% sucrose,2000m silver nitrate and 3.0% crysal were available in flower quality, but the 200 ppm silver nitrate solution treatment showed serious blackening of floral stems and resulted On negative effect in flower quality. Effect of gamma irradiation and all preservative solutions on the cut mum longevity were showed almost same tendency with rose cut flower longevity experiments. The 2% sugar dipping solution in mum cut flower showed the most superior preservative effect compared with the my other preservative solutions tested. Also non-irradiated treatment extended to flower up to complete wilt.

• Restorative Dentistry and Endodontics
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• v.10 no.1
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• pp.63-70
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• 1984

It was the purpose of this study to determine the galvanic current between a gold alloy inlay and four types of amalgam using the circuit through pulp chambers when the freshly extracted teeth with those restorations were brought into contact in a physiologic saline solution, and to investigate the effectiveness of cavity varnish or ammonated silver-nitrate on the surface of amalgam restoration in reducing galvanic current. The current was measured with current-to-voltage converter and recored on a physiograph 6630-257. The following results were obtained. 1. Generally, galvanic current decreased as the time elapsed. 2. Galvainc current decreased significantly in the first day and after then minimal change was observed until 30th day. 3. Initial galvanic current was 29.6 ${\mu}A$ in the cut amalgam and 24.5 ${\mu}A$ in Dispersalloy amalgam and after then the current was significantly decreased. 4. Initial galvanic current was 12.6 ${\mu}A$ in spherical amalgam (low copper amalgam) and 13.8 ${\mu}A$ in Tytin amalgam and the amount of change was lower in sperical amalgam and Tytin amalgam than that in lathe cut amalgam and Dispersalloy amalgam. 5. Painting ammoniated silver-nitrate or Copalite on the surface of amalgam resotration decreased initial galvanic current and ammoniated silver-nitrate is more effective in decreasing galvanic current than Copalite. 6. Galvanic current by contact between amalgam restoration and gold restoration increased abruptly and dropped rapidly becoming almost.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1342-1344
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• 1994

Silver-Nickel alloy has been used as a electrical contact material for low voltage, low current. Since the solubility between Ag and Ni is very low, it is difficult to produce Ag-Ni alloy by using conventional melting method and disperse Ni powder homogeneously in Ag matrix. In this study we have been produced fine Ag-Ni alloy powder by using coprecipitation method. Firstly, we have produced silver-nickel nitrate solution by dissolving the Ag and Ni ingot in nitric acid solution and then, coprecipitate (Ag, Ni)carbonate dropping Ag-Ni nitrate solution to sodium carbonate solution. (Ag, Ni) carbonate is heat-treated in $H_2$ atmosphere, $400^{\circ}C$ and it has been analysed by TGA, SEM, XRD, ICP. It is represented Silver-Nickel alloy powder in the particle range of $0.1{\sim}0.5{\mu}m$.

• Corrosion Science and Technology
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• v.6 no.6
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• pp.304-307
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• 2007

As to the reflection electrode of LCD (liquid crystal displays), silver-copper-gold alloy (hereafter, it is called as ACA (Ag98%, Cu1%, Au1%)) is an effective material of which weathering resistance can be improved more compared with pure silver. However, there is a problem that gold remains on the substrate as residues when ACA is etched in cerium ammonium nitrate solution or phosphoric acid. Gold can not be etched in these etchants as readily as the other two alloying elements. Gold residue has actually been removed physically by brushing etc. This procedure causes damage to the display elements. Another etchant of iodine/potassium iodide generally known as one of the gold etchants can not give precise etch pattern because of remarkable difference in etching rates among silver, copper and gold. The purpose of this research is to obtain a practical etchant for ACA alloy. The results are as follows. The cyanogen complex salt of gold generates when cyanide is used as the etchant, in which gold dissolves considerably. Oxygen reduction is important as the cathodic reaction in the dissolution of gold. A new etchant of sodium cyanide / potassium ferricyanide whose cathodic reduction is stronger than oxygen, can give precise etch patterns in ACA alloy swiftly at room temperature.

• Advances in nano research
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• v.10 no.4
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• pp.373-383
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• 2021

In this work, silver nitrate complexes of sulfanilamide-5-methyl-2-thiophene carboxaldehyde (SMTCA) ligand intercalated Zn/Al-layered double hydroxide [Ag-SMTCA-LDH] were synthesized for the potential application as an antimicrobial system. The SMTCA ligand was synthesized by reacting sulfanilamide and 5-methyl-2-thiophene carboxaldehyde in methanol and further complexation with silver nitrate metal ions [Ag-SMTCA]. The structural analyses of synthesized compounds confirmed an intercalation of Ag-SMTCA into Zn/Al-NO₃-LDH by flake/restacking method. SMTCA, Ag-SMTCA and Ag-SMTCA-LDH were characterized by ¹H nuclear magnetic resonance (¹H NMR) spectroscopy, Fourier-transform infrared (FTIR), ultraviolet-visible (UV-Vis) spectrophotometer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). It was found that Ag-SMTCA-LDH exhibited good antimicrobial activity against both gram-positive (Bacillus subtilis, [B. subtilis], Staphylococcus aures, [S. aureus]) and gram-negative (Escherichia coli, [E. coli], Pseudomonas aeruginosa [P. aeroginosa]) bacteria as well as excellent antioxidant activity.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2918-2922
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• 2010

We demonstrate a facile route to synthesize silver chloride nanocubes and derivative nanomaterials. For the synthesis of silver chloride nanocubes, silver nitrate and hydrochloric acid were used as precursors in ethylene glycol, and poly (vinyl pyrrolidone) as a surfactant. Molar ratio of the two precursors greatly influenced the morphology and composition of the final products. As-synthesized silver chloride nanocubes showed size-dependent optical properties in the visible region of light, which is likely due to a small amount of silver clusters formed on the surface of silver chloride nanocubes. Moreover, we show for the first time that simple reduction of silver chloride nanocubes with different reducing reagents leads to the formation of delicate nanostructures such as cube-shaped silver-nanoparticle aggregates, and silver chloride nanocubes with truncated corners and with silver-nanograin decorated corners. Additionally, we quantitatively investigated for the first time the evolution of silver chloride nanocubes to silver chloride nanocubes decorated with silver nanoparticles upon exposure to e-beam. Our novel and facile synthesis of silver chloride related nanoparticles with delicately controlled morphologies could be an important basis for fabricating efficient photocatalysts and antibacterial materials.

• Journal of the Korean Chemical Society
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• v.52 no.4
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• pp.380-386
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• 2008

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.325-328
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• 2011