• Textile Coloration and Finishing
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• v.11 no.4
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• pp.50-56
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• 1999

The adhesive properties of polyester cord in rubber matrix were investigated according to the surface modification. The polyester cord was oxidized in sodium hypochlorite solution, and graft-polymerized with acrylic acid under the irradiation with ultraviolet light, and then coated with resorcinol-formaldehyde latex (RFL). The modified surface was checked with scanning electron microscope. The adhesive properties were measured by the full-Out method, and evaluated with regard to the energy of adhesion and the maximum load. The polyester was not oxidized in sodium hypochlorite solution, so the surface was not able to etch to produce the coarse topology. As the concentration of acrylic acid and the reaction time were increased, the graft yields were also increased. It was considered that the acrylic acid would swell the polyester and diffuse easily to the inner side of substrate. The adhesive properties of polyeser to rubber matrix were affected by the surface condition. Namely, the maximum load was almost same, but the energy of adhesion was rather higher In the polyester grafted with acrylic acid than in control one. We concluded that the flexible aliphatic chains of polyacrylic acid situated in the interface of cord and rubber matrix were distributed well the stress and strain all over the filler resulting the high energy of adhesion.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1155-1156
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• 2006

In this paper, we analyzed the effect of EVA Sheet Gel Content depending on curing condition for photovoltaic module. Gel Content was measured by manufacturing Glass/EVA Sheet/Back Sheet scheme at several curing temperature and curing time. And the surface analysis of EVA Sheet depending on process condition could be observed using SEM(Scanning Electron Microscope). Through this experiment, we could confirm that there are differences on Gel Content of EVA Sheet and surface configuration depending on curing temperature and curing time. To find out the optical characteristic dependency on curing condition, Class/EVA Sheet/Glass scheme was fabricated. The optical transmittance of EVA Sheet at visible wavelength was enhanced 5% when compared to Glass/Glass scheme. And the transmittance of $130^{\circ}C$/4min, $110^{\circ}C$/4min, $160^{\circ}C$/6min process condition was higher at ultraviolet wavelength range. These curing conditions could be regarded as the best process for suppression the discoloration speed of EVA Sheet under UV light.

• Elastomers and Composites
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• v.50 no.2
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• pp.126-131
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• 2015

$C_{60}$ nanowhiskers were synthesized from $C_{60}$ by liquid-liquid interfacial precipitation (LLIP) using $C_{60}$-saturated toluene and isopropyl alcohol. The $WO_3$ nanoparticles were synthesized by adding $3.8{\times}10^{-4}$ mole amount of ammonium metatungstate hydrate ($H_{26}N_6O_{40}W_{12}{\cdot}H_2O$) to 500 ml of distilled water, and the resulting solution was heated on a hot plate for 4 h. The $C_{60}$ nanowhiskers/$WO_3$ nanocomposites were prepared with $C_{60}$ nanowhiskers and $WO_3$ nanoparticles in an electric furnace at $700^{\circ}C$ in an argon gas atmosphere for 2 h. The $C_{60}$ nanowhiskers/$WO_3$ nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. UV-vis spectroscopy was used to evaluate the performance of the $C_{60}$ nanowhiskers/$WO_3$ nanocomposites as a photocatalyst in the degradation of organic dyes, such as methylene blue (MB) and brilliant green (BG) under ultraviolet light (254 nm).

• The Korean Journal of Zoology
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• v.37 no.2
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• pp.232-239
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• 1994

RecA protein plans a central role in homologous recombination and DNA repair in Escherichia cofi (E. colD. The function 8nd structure of this protein are universal in prokarvotes and also conserved in eukaryotes such as yeast. The RecA-like protein with 74 lInDa in size has already been identified and purified from a fission yeast Schizosaccharomyces pombe (5. pommel (Lee, 19911. From this study it was revealed that the RecA-like protein of 5. pombe was highly inducible to various DNA damaging agents and inhibitors of nucleotide pool svnthesizins enzymes. The cellular level of the 5. pombe RecA-like protein wi,u markedly increased, upto 5- to 10-fold, by treatment with various DNA-damains agents including ultraviolet (UV) light, methyl methanesulfonate WS),4-nitroquinoline-1-oxide (4-NQO), and mitomycin-C (MMC), similar to E. cofi RecA protein. Interestingly, the protein level was also increased by inhibitors of nucleotide pool forming enzlwnes such as methotrexate (MTX) and hvdroxvurea (HU). The most effective doses for the inducibility of 4-NQO, MMS, W, MMC, MTX, and HU were 0.2 Ug/ml, 30 mM, 200 J/ma, 0.4 $\mus/ml,$ 1 Ug/ml, and 100 mM, respectively. The range of effective duration time for the inducibilitv of RecA-like protein was from 270 to 450 mins. These results suggest that the 5. pombe RecA-like protein also platys an imortant role in cellular responses to DNA damage as in E. coli system.

• Elastomers and Composites
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• v.51 no.1
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• pp.49-55
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• 2016

Nanosized cobalt disulfide ($CoS_2$) particles were synthesized with 0.08 M cobalt chloride hexahydrate ($CoCl_2{\cdot}6H_2O$) and 0.2 M sodium thiosulfate pentahydrate ($Na_2S_2O_3{\cdot}5H_2O$) dissolved in distilled water under microwave irradiation. $[C_{60}]Fullerene-CoS_2$ nanocomposites were prepared with nanosized $CoS_2$ particles and [$C_{60}$]fullerene as heated by $700^{\circ}C$ for 2 h in an electric furnace. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) identified the heated $[C_{60}]fullerene-CoS_2$ nanocomposites. Heated $[C_{60}]fullerene-CoS_2$ nanocomposites were investigated the activity of photocatalytic degradation as a catalyst in various organic dyes like acid yellow 23, methylene blue, methyl orange, and rhodamine B with ultraviolet light at 254 nm by UV-vis spectrophotometer.

• Bulletin of the Korean Space Science Society
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• 2009.10a
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• pp.35.2-35.2
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• 2009

One possible channel for the formation of dwarf galaxies involves birth in the tidal tails of interacting galaxies. We report the detection of a bright UV tidal tail and several young tidal dwarf galaxy candidates in the post-merger galaxy NGC 4922 in the Coma cluster. Based on a two-component population model (combining young and old stellar populations), we find that its light predominantly comes from young stars (a few Myr old). The Galaxy Evolution Explorer (GALEX) ultraviolet data played a critical role in the parameter (age and mass) estimation. Our stellar mass estimates of the tidal dwarf galaxy candidates are ~10^{6-7} M_sun, typical for dwarf galaxies.

• Journal of Yeungnam Medical Science
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• v.8 no.1
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• pp.215-219
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• 1991

We report a case of piroxicam-induced photosensitive dermatitis in a 54-year-old female. She had taken oral piroxicam and was exposed to the sunlight on her way home for a few minutes. Several hours after the sun-exposure she developed well-defined, confluent, erythematous plaques and numerous vesicobullae with pruritus and prickling sensation on the sun-exposed areas. A phototest was done on her first visit. The minimal erythemogenic dose(2J/$cm^2$) of ultraviolet(UV) A was markedly decreased whereas that of UVB was within a normal limit. Visible light irradiation for 30 minutes did not cause skin lesions. Six months after the initial skin lesions, a photopatch test with 1% and 10% piroxicam solution followed by UVA(10J/$cm^2$) irradiation showed positive responses on both concentrations.

• Journal of Fashion Business
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• v.18 no.5
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• pp.69-81
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• 2014

Fabric made of 100% silk was dyed with Undaria pinnatifida extracts under different conditions such as varing colorant concentration, temperature, time and dyebath pH. The dye uptake (K/S, value), CIE L*,a*,b* and Munsell values of the dyed samples and mordanted samples were measured. Colorfastness, antibacterial property and UV protection property were also evaluated. As colorants concentration increased, the dye uptake increased progressively and maximum color strength was obtained at 100% V/V. Dye uptake also increased with increasing temperature and time, and the maximum color strength was obtained at $80^{\circ}C$ and 60min. With pre-mordanting, the color of the Al and Fe mordanted silk fabrics was yellow on the Munsell color system, while the Cu mordanted fabric was a greenish color. Al and Fe post-mordanted fabrics had a yellow tone, and the Cu post-mordanted fabric had a yellow greenish tone. The light fastness property of the Cu mordanted silk fabric was relatively good, The effect of Al and Fe mordanting on fastness was insignificant. The antibacterial activity of dyed and unmordanted silk fabric was excellent, whereas fabric dyed and mordanted with Undaria pinnatifida extract demonstrated superior ultraviolet protection.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.411-416
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• 2010

Interest in application of ultraviolet light technology for primary disinfection of potable water in drinking water treatment plants has increased significantly in recent years. The efficacy of disinfection processes in water purification systems is governed by several key factors, including reactor hydraulics, disinfectant chemistry, and microbial inactivation kinetics. The objective of this work was to develop a computational fluid dynamics(CFD) model to predict velocity fields, mass transport, chlorine decay, and microbial inactivation in a continuous flow reactor. In this paper, It describe the how to design optimal UV disinfection device for ground water, BWT and rainwater. Spring shape instrument silver coated located in inner side of disinfection chamber. It make lead the active flowing movement target water and maximize disinfection performance. To search the optimal design method, it was performed computer simulation with 3D-CFD discrete ordinates model and manufactured prototype. Using proposed design method, performed simulation and proved satisfied performance.

• Journal of Powder Materials
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• v.28 no.1
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• pp.25-30
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• 2021

The surface of silicon dummy wafers is contaminated with metallic impurities owing to the reaction with and adhesion of chemicals during the oxidation process. These metallic impurities negatively affect the device performance, reliability, and yield. To solve this problem, a wafer-cleaning process that removes metallic impurities is essential. RCA (Radio Corporation of America) cleaning is commonly used, but there are problems such as increased surface roughness and formation of metal hydroxides. Herein, we attempt to use a chelating agent (EDTA) to reduce the surface roughness, improve the stability of cleaning solutions, and prevent the re-adsorption of impurities. The bonding between the cleaning solution and metal powder is analyzed by referring to the Pourbaix diagram. The changes in the ionic conductivity, H2O2 decomposition behavior, and degree of dissolution are checked with a conductivity meter, and the changes in the absorbance and particle size before and after the reaction are confirmed by ultraviolet-visible spectroscopy (UV-vis) and dynamic light scattering (DLS) analyses. Thus, the addition of a chelating agent prevents the decomposition of H2O2 and improves the life of the silicon wafer cleaning solution, allowing it to react smoothly with metallic impurities.