• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.43-49
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• 2008

Purpose: The current study was conducted to evaluate the compatibility of UV-A blocking contact lens on eye protection with regular contact lens. Methods: The protective activity of regular contact lens (UV-A blocking: 20%) and UV-A blocking contact lens (UV-A blocking: 85%) on the denaturation of RNase A, catalase, and superoxide dismutase (SOD) induced UV-A irradiation were compared by acrylamide gel electrophoresis. The enzyme solutions were irradiated with UV-A for 1, 3, 6, 24 and 96 hours at the wavelength of 365 nm. Covering area with contact lenses were varied as 50%, 70% and 100% according to the calculation of blocking areas of anterior eye that could be covered with RGP lens, soft contact lens, and eye glasses, respectively. Results: Denaturations of RNase, catalase and SOD were exaggerated when they were exposed to UV-A for a longer period. The denaturation was effectively prevented by UV-A blocking contact lens compared to regular contact lens. The capability of UV-A blocking contact lens was considerably reduced when the covering area with contact lens decreased and exposure time to UV-A extended. Conclusion: Therefore, it would be suggested that wearing contact lens for a long time under sunlight is carefully considered since the activity of UV-A blocking contact lens against UV-A irradiation may not be enough to protect enzymes presented in eyes when exposure time to UV-A increased.

• Journal of Photoscience
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• v.9 no.2
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• pp.329-331
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• 2002

There is a difference in the inhibitory effects to supplemental UVB (wavelengths 280 to 320 nm) among Japanese rice (Oryza sativa L.), the cultivar Norin I is less resistant while the cultivar Sasanishiki is resistant. UVB induces photodamage in DNA. Cyclobutane pyrimidine dimer (CPD) is a major UV-induced DNA lesion. Photorepair, which is mediated by photolyase, is the major pathway in plants for repairing CPD. We have analyzed CPD induction and repair in Sasanishiki and its close relative Norin I using alkaline agarose gel electrophoresis. Norin I is deficient in CPD photoreactivation and excision, thus UV sensitivity correlates with deficient dimer repair [I]. The photorepair deficiency in Norin I results from a functionally altered photolyase with a photoflash analysis [2]. In this paper, we examined the UVB-sensitivity of several other UV-sensitive and -resistant cultivars and found that the CPD photolyase activity was deficient in UV-sensitive ones. It was also evident that there was a variation in the deduced amino acid sequences of CPD photolyases of the UV-sensitive and -resistant cultivars, whereas each deduced amino acid sequence of the UV-sensitive cultivars and of the UV-resistant ones was the same. These results suggest that the difference in the CPD photolyases of UV-sensitive and -resistant rice might be due to the structural alteration of CPD photolyase.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.566-569
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• 2005

The extracellular polysaccharide...(EPS) has been used in a wide variety of industrial applications because of gel formation, emulsion stability, control of the surface tension, water absorption and film formation etc. In this study, inhibitory activity on tyrosinase and inhibitory activity on angiotensin converting enzyme...(ACE) are determined. UV adsorption wavelength, beads formation of EPS were investigated. In the result, in 1%(w/v) EPS concentration, EPS had inhibitory activity of 71.8% on tyrosinase and inhibitory activity of 61.5% on angiotensin converting enzyme in 1.5% EPS concentration. Adsorption wavelength of EPS was UV-B,C . Beads based on EPS were prepared by w/o emulsion method and the shape of EPS beads observed by SEM was spherical and uniform.

• Analytical Science and Technology
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• v.7 no.1
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• pp.17-23
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• 1994

Through sol-gel process, inorganic/organic composite as a dye host was made. It was observed that this composite has about 90% of trnasmittance by UV/VIS spectrophotometer. The transmittance is the most important requirement to decide whether the composite could apply or not as the dye host. The transmittance was increased with decreasing HCl as a catalyst, aging time, and amount of PDMS. Also, fluorescent and transmittant charateristics of Rhodamine 6G Perchlorate that was doped into ORMOSIL were measured. The fluorescent intensity was increased and the trnasmittance was decreased with rising gelling temperature.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.27 no.1
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• pp.73-81
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• 2001

For an attempt to develop safe materials protecting UV-induced skin damage, plant extracts were evaluated for their antioxidative and free radical scavenging activities. From the results of these screening procedures, the ethanol extract of the flowers of Prunus persica was selected for further study. It was found that Prunus persica (50-200 $\mu\textrm{g}$/㎖) inhibited UVB-induced DNA damage measured by tail moment in the Single Cell Gel Electrophoresis(COMET assay) and inhibited UV-induced lipid peroxidation, expecially against UVB-induced peroxidation at higher than 10 $\mu\textrm{g}$/㎖. Also P.persica(100∼1,000 $\mu\textrm{g}$/㎖) inhibited the amount of $\^$14/C-arachidonic acid metabolites release from UVB-irradiated keratinocytes and it possessed the protective activity against UV-induced cytotoxicity of keratinocytes. All these results indicate that the flowers of P. persica extract may be beneficial for protection UV-induced skin damage when topically applied.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.2
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• pp.93-98
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• 2020

We investigated the effect of a post-annealing process using ultraviolet (UV) light on the electrical properties of solution-processed InZnO (IZO) thin-film transistors (TFTs). UV light was irradiated on IZO TFTs for different time periods of 0s, 30s, and 90s. We measured transfer and retention stability curves to evaluate the performance of the fabricated TFTs. In addition, we measured height, amplitude, and phase AFM images to analyze changes in the surface and morphology of the devices. AFM measurements were performed by setting the drive amplitude of the cantilever tip to 47.9 mV in tapping mode, then dividing the device surface into 500 nm × 500 nm. In the case of IZO TFT irradiated with UV for 30s, the electron mobility and I_on/I_off ratio were improved, the threshold voltage was reduced by approximately 2 V, and the subthreshold swing also decreased form 1.34 V/dec to 1.11 V/dec.

• Journal of the Korean Ceramic Society
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• v.44 no.3 s.298
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• pp.137-141
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• 2007

$La_{2}O_{3}-TiO_{2}-SiO_{2}$ glass, a type that could not obtained so far by the conventional melting method, was prepared successfully using a sol gel process. Glass derived with the sol-gel process has compositions of $5La_{2}O_{3}-5TiO_{2}-90SiO_{2},\;5La_{2}O_{3}-10TiO_{2}-85SiO_{2}$, and $5La_{2}O_{3}-20TiO_{2}75SiO_{2}$. The UV-visible absorption edge of all glass compositions was below 400 nm. The measured density is in the range of 2.55-2.89, and was nearly identical to the calculated density and the refractive index of the glasses derived from the sol-gel ranges from 1.545 to 1.645. The molar additive coefficient of $TiO_{2}$ measured in this ternary system is lower than the calculated value, while the value of $La_{2}O_{3}$ is higher.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1809-1816
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• 2014

This study demonstrates gel-to-fluid transition temperatures of polydiacetylene bilayer vesicles could play important roles in their colorimetric transition temperatures. We prepared five types of polydiaceylene vesicles with 10,12-pentacosadiynoic acid (PCDA) and cholesterol (0-40 mol % of total content). From temperature-dependent observations of the optical signals (colors and UV-vis spectra), the blue-to-red colorimetric transition temperatures of polydiacetylene vesicles were decreased with the cholesterol contents. A further study with microcalorimetry and dynamic light scattering revealed that the polydiacetylene vesicles first underwent gel-to-fluid transitions, which were followed by event(s) responsible for the colorimetric transitions. Energies required for each event were quantified from analysis of the peaks in the microcalorimetry thermograms. The inclusion of cholesterol in the vesicles decreased both the gel-to-fluid and the colorimetric transition temperatures, suggesting that the colorimetric transition of the polydiacetylene vesicles was mediated by the former event although the event was not the direct reason for the color change.

• Korean Journal of Materials Research
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• v.15 no.6
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• pp.419-425
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• 2005

In this paper, we describe the luminescent properties of the phosphors synthesized via sol-gel technique. When the phosphor prepared by sol-gel technique, reaction factors, such as pH condition, $R_w$ and drying temperature affected the luminescent intensity, particle size and morphology of final product. Therefore, we attempt to control these reaction factors in order to improve the luminescent efficiency of phosphors. As a result of our study, when the acid catalyst (HCl) was used, emission intensity was higher than the case of base catalyst $(NH_4OH)$. The product prepared at $R_w=60$ indicated the maximum intensity. As the increase of the $R_w$ value, the particle was agglomerated and emission intensity was decreased. Finally, optimum drying temperature of gel was found to be$ 180^{\circ}C$.

• 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.