• Textile Coloration and Finishing
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• v.21 no.2
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• pp.14-21
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• 2009

In this article, silk fabric was treated with silver nitrate ($AgNO_3$) as oxidizing agent, with conditions such as concentration, and treating time, and subsequently treated with reducing agents such as sodium boron hydride ($NaBH_4$) and sodium sulfide ($Na_2S$) to obtain cathodic coloration. After coloration of silk fabric, dyeing properties (K/S value), colorfastnesses such as wash, rubbing and light, and antibacterial activity property were examined. $AgNO_3$ treating time and reducing time did not influence K/S value, whereas the pH value at alkaline region showed a high K/S value of silk fabric. The cathodic colorations of silk fabric with both of reducing agents at $30^{\circ}C$ have excellent color fastnesses. Also the high antibacterial activities were obtained by the treatment with silver nitrate even at 1% of lower concentration.

• Korean Journal of Veterinary Research
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• v.49 no.2
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• pp.135-139
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• 2009

Streptomyces (S.) fradiae is a microbe with broad-spectrum antimicrobial activity, isolated from soil. In the present study, antibacterial effects of S. fradiaea against Salmonella (S.) gallinarum was determined. S. fradiae inhibited growing of S. gallinarum in Luria-Bertani media agar. Moreover, ingestion of S. fradiae markedly inhibited mortality of chickens experimentally infected with S. gallinarum. There is no side effect by S. fradiaeon, in safety of chickens and antibiotic material residues in chicken meat. Taken together, S. fradiae have the antibacterial effects against S. gallinarum. Therefore, we concluded that S. fradiae might be a good microbial candidate for treatment or control of fowl typhoid in chickens.

• Carbon letters
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• v.23
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• pp.17-21
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• 2017

Polyurethane (PU) nanofibers containing graphene oxide (GO) and Ag doped functionalized reduced graphene oxide (Ag-RGO) were successfully prepared via the electrospinning technique. The uniform distribution of GO sheets along with Ag nanoparticle in the nanofibers was investigated by scanning electron microscopy and the elemental mapping technique. X-ray diffraction and thermal gravimetric analysis verified the presence of GO and Ag in the bicomposite nanofibrous mats. Antibacterial tests against Escherichia coli demonstrated that the addition of GO and Ag-RGO to the PU nanofiber greatly enhanced bactericidal efficiency. Overall, these features of the synthesized nanofibers make them a promising candidate material in the biomedical field for applications such as tissue engineering, wound healing, and drug delivery systems.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.42-47
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• 2018

This work reports a facile and effective antibacterial coating for oxide substrates. As a coating material, a random copolymer, abbreviated as poly(TMSMA-r-PEGMA), was synthesized by radical polymerization of 3-(trimethoxysilyl)propyl methacrylate (TMSMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA). Polymeric self-assembled monolayers of poly(TMSMA-r-PEGMA) were formed on various inorganic oxide substrates, including silicon oxide, titanium dioxide, aluminum oxide, and glass, via the simple dip-coating process. The polymer-coated substrates were characterized by ellipsometry, contact angle measurements, and X-ray photoelectron spectroscopy. The bacterial adhesion on the polymer-coated substrates was completely suppressed compared to that on the uncoated substrates.

• Transactions on Electrical and Electronic Materials
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• v.15 no.5
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• pp.275-278
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• 2014

We deposited TiAgN and ZrAgN nanocomposite coatings on pure Titanium specimens, by using arc ion plating (AIP) with single alloy targets. TiAg ZrAg alloy targets of 5 wt.%, 10 wt.% silver content by vacuum arc remelting (VAR), followed by homogenization for 2 hours at $1,100^{\circ}C$ in non-active Ar gas atmosphere and characterized these samples for morphology and chemical composition. We investigated the biocompatibility of TiAg and ZrAg alloys by examining the proliferation of L929 fibroblast cells by MTT test assay, after culturing the cells ($4{\times}10^4cells/cm^2$) for 24 hours; and exploring the antibacterial properties of thin films by culturing Streptococus Mutans (KCTC3065), using paper disk techniques. Our results showed no cytotoxic effects in any of the specimens, but the antibacterial effects against Streptococus Mutans appeared only in the 10 wt.% silver content specimens.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.2
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• pp.8-15
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• 2014

A novel antibacterial paper coated with chitosan-based silver (Ag) nanocomposite prepared by green synthesis has been investigated for a wide range of application in food, agricultural and medical packaging. Green synthesis of Ag nanoparticles (AgNPs) was carried out by a chemical reaction involving a mixture of chitosan-silver nitrate (AgNO3) in an autoclave at 15 psi, $121^{\circ}C$, for 15-120 sec. AgNPs and their formation in chitosan were confirmed by both UV-Vis spectroscopy and transmission electron microscope (TEM). Fourier transform infrared spectroscopy (FTIR) study showed that free amino groups in chitosan act as an effective reductant and AgNPs stabilizer. Antibacterial test of coated paper with as-prepared chitosan-AgNPs was performed qualitatively against E. coli based on the formation of halo zones around coated papers and it was shown to be effective in suppressing the growth of E. coli with increasing Ag contents in coating layer.

• Korean Journal of Materials Research
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• v.28 no.1
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• pp.24-31
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• 2018

This study reports an environment-friendly synthetic strategy to process nickel oxide nanocrystals. A mesoporous nickel oxide nanostructure was synthesized using an environmentally benign biomimetic method. We used a natural rambutan peel waste resource as a raw material to ligate nickel ions to form nickel-ellagate complexes. The direct decomposition of the obtained complexes at $700^{\circ}C$, $900^{\circ}C$ and $1100^{\circ}C$ in a static air atmosphere resulted in mesoporous nickel oxide nanostructures. The formation of columnar mesoporous NiO with a concentric stacked doughnuts architecture was purely dependent on the suitable direct decomposition temperature at $1100^{\circ}C$ when the synthesis was carried out. The prepared NiO nanocrystals were coated on cotton fabric and their antibacterial activity was also analyzed. The NiO nanoparticle-treated cotton fabric exhibited good antibacterial and wash durability performance.

• Korean Journal of Plant Resources
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• v.30 no.3
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• pp.311-317
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• 2017

This study was conducted with the aim of evaluating the antibiotic effects of leaves, stems, and roots in yacon (Smallanthus sonchifolius). Antibacterial activity of leaf extract by disk diffusion method with Bacillus subtilis and Escherichia coli respectively showed 13.3 and 13.75mm diameters of clear zone. There was no significant difference between the stems and leaves. The minimum inhibitory concentration of leaves' heating and agitation extraction showed a restrain of strain at 1mg/ml, but the stems and root extract did not appear. Yacon is a functional antibacterial material, and methanol extraction is more effective than water. This research was to investigate the growth stage of collection has the most effective antibacterial effects. It has collected yacon's leaves from June to October, which is an appropriate time for collection right before reaping. Yacon leaf has antibacterial effects on Bacillus subtilis, Escherichia coli, Enterococcus faecium, and Salmonella enteritifis. There were no significant differences by the growth stage of collection. Leaves collected in July are high in phenol which helps in sulfating activity works well considering the high scavenging capability of DPPH. Leaves collected in September are high in total flavonoid.

• Korean Journal of Materials Research
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• v.33 no.1
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• pp.1-7
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• 2023

The physical and antibacterial properties of ophthalmic lenses fabricated by copolymerization with hydrogel monomers using two types of graphene were measured, and their usability as contact lens materials was analyzed. For polymerization, silicone monomers, including SID-OH, 3-(methacryloxy)propyl tris(trimethylsiloxy)silane, and decamethylcyclopentasiloxane, were used, and N,N-dimethylacetamide, ethylene glycol dimethacrylate as a crosslinking agent, and azobisisobutyronitrile as an initiator were added. Also, graphene oxide nanoparticle (GON) and graphene nanoplate (GNP) were used as an additive, and the physical properties of the lenses fabricated after copolymerization were evaluated. The fabricated lenses satisfied the basic physical properties of general hydrogel contact lenses and showed the characteristics of lenses with high water content, and the disadvantage of very weak durability, due to low tensile strength. However, it was confirmed that the tensile strength and antibacterial properties were greatly improved by adding GON and GNP. With GON, the oxygen permeability and refractive index of the fabricated lenses were slightly improved. Therefore, it was determined that the graphene materials used in this study can be used in various ways as a contact lens material.

• Fashion & Textile Research Journal
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• v.25 no.1
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• pp.62-71
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• 2023

Recently, interest in natural fabric materials that are not harmful has increased, and hemp is being studied as a new eco-friendly product. This study produced hemp fabric with improved flexibility and increased antibacterial properties by blending it with Hanji yarn. Various weaving methods were proposed to overcome the rough physical properties of hemp, and the functions of the developed products were evaluated through antibacterial tests. The mixing ratios of hemp and Hanji yarns was 50% hemp: 50% Hanji weft, 70% hemp: 30% Hanji weft, 30% hemp: 70% Hanji weft, and 100% hemp. Overall, the higher the ratio of Hanji yarn, the higher the fastness property, and the higher the ratio of hemp yarn, the higher the flexibility of the fabric, which was evaluated to be comfortable to wear. The 99.9% antibacterial properties of hemp products were considered to contribute to maintaining the health of modern people. Owing to its high intensity and high air permeability, it is considered highly usable in the production of children's clothing with a lot of activity. It was evaluated as an advantage that the disadvantage of hemp, which was limited as a material for summer clothing, was broadened to use for all seasons due to the fusion of Hanji. Otherwise, low consumer satisfaction as an outdoor wear is a disadvantage because hemp products had low elasticity and wrinkles.