• Korean Journal of Materials Research
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• v.20 no.8
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• pp.418-422
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• 2010

As a starting material, BCP (biphasic calcium phosphate) nano powder was synthesized by a hydrothermal microwave-assisted process. A highly porous BCP scaffold was fabricated by the sponge replica method using 60 ppi (pore per inch) of polyurethane sponge. The BCP scaffold had interconnected pores ranging from $100\;{\mu}m$ to $1000\;{\mu}m$, which were similar to natural cancellous bone. To realize the antibacterial property, a microwave-assisted nano Ag spot coating process was used. The morphology and distribution of nano Ag particles were different depending on the coating conditions, such as concentration of the $AgNO_3$ solution, microwave irradiation times, etc. With an increased microwave irradiation time, the amount of coated nano Ag particles increased. The surface of the BCP scaffold was totally covered with nano Ag particles homogeneously at 20 seconds of microwave irradiation time when 0.6 g of $AgNO_3$ was used. With an increased amount of $AgNO_3$ and irradiation time, the size of the coated particles increased. Antibacterial activities of the solution extracted from the Ag-coated BCP scaffold were examined against gram-negative (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus). When 0.6 g of $AgNO_3$ was used for coating the Ag-coated scaffold, it showed higher antibacterial activities than that of the Ag-coated scaffold using 0.8 g of $AgNO_3$.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.3
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• pp.26-32
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• 2004

Objective: The aim of this work is to investigate the antibacterial activity of the essential oil obtained from Artemisia lavandulaefolia (A. lavandulaefolia), as the development of microbial resistance to antibiotics make it essential to constantly look for new and active compounds effective against pathogenic bacteria. Method: The aerial parts of A. lavandulaefolia (1 kg) were subjected to steam distillation for 3 h, using a modified Clevenger type apparatus in order to obtain essential oil. Diethyl ether was the extracting solvent kept at 25?. The essential oil were analyzed by gas chromatography (GC) and gas chromatography／mass spectrometry (GC／MS). The essential oil and the composition were tested for antimicrobial activities against 15 different genera of oral bacteria. Ninety-nine compounds accounting for 94.74$\%$<／TEX> of the oil were identified. The main compounds in the oil were 1,8-cineole (5.63$\%$), yomogi alcohol (4.49$\%$), camphor (4.92$\%$), a-caryophyllene (16.10$\%$), trans-a-famesene (5.09$\%$), a-terpineol (3.91$\%$), borneol (5.27$\%$), cis-chrysanthenol (6.98$\%$), and a-humulene oxide (3.33$\%$). The essential oil and its compounds were tested for antimicrobial activity against 10 different genera of oral bacteria. Conclusion: The essential oil of A. lavandulaefolia exhibited considerable inhibitory effects against all obligate anaerobic bacteria (MICs, 0.025 - 0.05 ㎎／ml) tested, while their major compounds demonstrated various degrees of growth inhibition

• Journal of the Korean Applied Science and Technology
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• v.39 no.4
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• pp.488-498
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• 2022

The effects of 1,3-Butanediol, 1,2-Pentanediol, and 1,2-Hexanediol in surfactant solutions on cmc, surface tension, foaming and emulsifying properties were determined. The addition of diols in aqueous surfactant solution decreased cmc and surface tension, and enhanced the foaming and emulsifying power. This trend is more significant by the longer hydrocarbon chain length of the diols. This property was confirmed because the diol's alkyl chain and the hydrophobic interaction with the surfactant reduce the cohesive force of water and increase the interaction between the head groups of the surfactant at interface. In addition, MIC test was conducted to determine the preservative power of each diol, and as a result, the antibacterial activity was effective in the order of 1,2-HDO > 1,2-PDO > 1,3-BDO. The results of this study show that diol can be applied to cosmetics as an auxiliary surfactant and antibacterial agent.

• Journal of Powder Materials
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• v.21 no.1
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• pp.16-20
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• 2014

In order to fabricate the porous $Al_2O_3$ with dispersion of nano-sized Cu particles, freeze-drying of camphene/$Al_2O_3$ slurry and solution chemistry process using Cu-nitrate are introduced. Camphene slurries with 10 vol% $Al_2O_3$ was frozen at $-25^{\circ}C$. Pores were generated by sublimation of the camphene during drying in air. The sintered samples at 1400 and $1500^{\circ}C$ showed the same size of large pores which were aligned parallel to the sublimable vehicles growth direction. However, the size of fine pores in the internal walls of large pores decreased with increase in sintering temperature. It was shown that Cu particles with the size of 100 nm were homogeneously dispersed on the surfaces of the large pores. Antibacterial test using fungus revealed that the porous $Al_2O_3$/1 vol% Cu composite showed antifungal property due to the dispersion of Cu particles. The results are suggested that the porous composites with required pore characteristics and functional property can be fabricated by freeze-drying process and addition of functional nano particles by chemical method.

• Journal of Fashion Business
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• v.23 no.3
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• pp.23-34
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• 2019

The aim of this study is to explore the possibility utilizing Rhododedron brachycarpum as a new natural dye resource. It was dyed in silk fabric according to different dyeing conditions such as dye concentration, dye bath temperature, dyeing time and dye bath pH. The effect of the mordanting conditions were estimated as dyeability and color changes. Additionally, the colorfastness, antibacterial property, ultraviolet protection properties of the dyed and mordanted silk fabrics were examined. The water-soluble dye of Rhododedron brachycarpum extracted with distilled water was expressed as Yellow Red color. The dye-abilities of silk generally increased depending on the increasing values of dye concentration, dye bath temperature and dyeing duration. The highest K/S values were obtained at a dye concentration of 100% (v/v), a dye bath temperature of $90^{\circ}C$, a dyeing duration 120 minutes and a dyeing of pH 2. The light fastness of dyed and Cu mordanted silk fabrics were found to be 4 grade while Al, Fe mordanted silk fabrics were found to be 2~3 grade. The dry cleaning and rubbing fastness were excellent or good. The fade of washing fastness was not good, however, the stain of washing fastness was excellent. The dyed and Al, Cu mordanted silk fabrics indicated 99.9% reduction rate. The dyed and the mordanted fabrics showed very good ultraviolet protection factors.

• Journal of the Korean Chemical Society
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• v.61 no.4
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• pp.179-184
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• 2017

In this paper, a $ZnO/SiO_2$ nano-composite was prepared by a simple chemical method at room temperature. For the synthesis of ZnO nanoparticles (NPs), a sonochemical method was used, and $SiO_2$ NPs were prepared by precipitation method. The formation of $ZnO/SiO_2$ NCs was characterized by X-ray diffractometer (XRD) and confirmed by field-emission scanning electron microscopy (FE-SEM) and Fourier transform infra-red spectroscopy(FT-IR). The photocatalytic properties of $ZnO/SiO_2$ NCs formed at different concentrations of $SiO_2$ were evaluated by rhodamine-B dye. It was confirmed that increasing $SiO_2$ concentration resulted in an increase in the photocatalytic property. In addition, the antibacterial activity of $ZnO/SiO_2$ NCs was conducted against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). As a result, the antibacterial activities of E.coli and S. aureus were increased in the presence of thick SiO NPs layer.

• Textile Coloration and Finishing
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• v.13 no.5
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• pp.48-48
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• 2001

The effects of silane coupling agent on the performance properties of cotton fabrics treated with loess and its washing durability were investigated. Mean average diameter of loess was 17.88㎛ and main components were SiO₂, Al₂O₃ and Fe₂O₃. By using the cationic agent, the dyeability of cotton fabrics was improved. The washing durability, antibacterial property and deodorization rate were improved and very good emissivities of far infra-red rays were obtained by using the silane coupling agent. And also the mechanical properties of cotton fabrics, such as primary hand values, were improved.

• Textile Coloration and Finishing
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• v.13 no.5
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• pp.336-345
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• 2001

The effects of silane coupling agent on the performance properties of cotton fabrics treated with loess and its washing durability were investigated. Mean average diameter of loess was $17.88\mu{m}$ and main components were $SiO_2,\;Al_2O_3\;and\;Fe_2O_3$. By using the cationic agent, the dyeability of cotton fabrics was improved. The washing durability, antibacterial property and deodorization rate were improved and very good emissivities of far infra-red rays were obtained by using the silane coupling agent. And also the mechanical properties of cotton fabrics, such as primary hand values, were improved.

• Textile Coloration and Finishing
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• v.16 no.6
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• pp.35-43
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• 2004

This study surveys the physical properties of ATY produced with FDY and POY. ATY is made with 70d Nylon FDY and 80d Nylon POY using AIKI air jet texturing machines, respectively. The processing parameters such as air pressure and yam speed are varied, and air pressure is varied ranging with 8.5bar, l0.5bar and 1l.5bar, and yarn speed is varied ranging with 400m/mim, 450m/mim, and 500m/min. The various physical properties of ATY made by POY and FDY denier, wet shrinkage, dry shrinkage, tensile properties, thermal stress and instability are measured and discussed with air pressure and yam speed. The shrinkage simulation of ATY is performed for analysing the process shrinkage on the dyeing and finishing processes.

• Fashion & Textile Research Journal
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• v.6 no.6
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• pp.803-809
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• 2004

In order to activate the characteristics of charcoal in fiber systems, this was carried out to experiment with the particle size from two micrometers to ten micrometers of charcoal powders on cotton fabrics. The results obtained were as follows; The fabrics were dyed with gray colors by charcoal. The K/S values, that were indicative of the dye affinity, became higher as the increase of dyeing temperature, dyeing time, and dyeing concentration. Also it was confirmed the morphology of the fiber surfaces adsorbed with the particle size from two micrometers to four micrometers of charcoal powder by scanning electronmicronscope. The cotton fabrics dyed by charcoals generally recorded 3-4 degree of wash fastness, 4-5 degree of dry-cleaning fastness, 4-5 degree acidic and alkaline perspirations and water fastness. In connection with the functional properties, cotton fabrics dyed with charcoal appeared that antibacterial, deodorization, far infrared emissivity were improved. Especially the deodorization was improved greatly by using charcoal.