• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.4
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• pp.750-756
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• 1997

The purpose of the study was to investigate a transmittance rate of UVB (Ultraviolet B) through summer fabrics and a protection rate of summer fabric from UVB. The subjects were randomly selected 159 fabrics from Korean common summer fabrics. The protection rates of 159 fabrics from UVB were measured by UVB lamp and UVB sensor, and 14 fabrics among these fabrics were selected for an assay of MTT(3-(4, 5-dimethylthiazol-2-yl) -2, 5 -diphenyltetrazolium). The protection rate of fabrics from cell toxicity of UVB was measured by investigating the difference of the amount of cell toxic substance on between fabrics covered with and without HeLa cell The average protection rate of 159 fabrics from UVB was 95.08%. As result findings, three negative correlations were found between: 1) the transmittance rate of UVB and the amount of MTT on fabrics (y=0.0373+0.O0518 x, r=-0.9323, p<0.001); 2) the air permeability of fabrics and the amount of MTT (r: -0.79, p< 0.01); 3) the air permeability of fabrics and the protection rate of fabrics from UVB (r=0.89, p<0.01). However, there was no effect of thickness of fabrics on the protection rate from UVB and the amount of MTT.

• Journal of Sensor Science and Technology
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• v.30 no.6
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• pp.381-383
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• 2021

Light-activated metal oxide gas sensors have been investigated in recent decades. Light illumination enhances the sensing attributes, including the operational temperature, sensitivity, and selectivity. Unfortunately, high operating temperature is a major problem for gas sensors because of the huge energy consumption. Therefore, the importance of light-activated room-temperature sensing has increased. This paper reviews recent light-activated sensors and their sensing mechanisms with a specific focus on metal oxide gas sensors. Studies use the outstanding ZnO and SnO₂ sensors to research photoactivation when illuminated by various sources such as ultraviolet (UV), halogen lamp, or monochromatic light. Photon induction generates electron-hole pairs that increase the number of adsorption sites of gas molecules and ions improving the sensor's sensing properties.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.4
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• pp.761-768
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• 2019

In this paper, the aim is to develop plasma heater products combining the sterilization and purification functions of low-temperature plasma lamp method with the function of vertical heating system using wavelengths of vacuum magnetic (VU). Through this process, the government aims to improve the cultivation environment of crops in greenhouses or facility houses and to increase their storage capacity by increasing the freshness of stored crops such as free-temperature storage. In addition, real-time monitoring technologies will be incorporated that will enable users to identify and respond to changes within greenhouses in real time by utilizing ICT technologies.

• Korean Journal of Food Science and Technology
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• v.3 no.3
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• pp.178-184
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• 1971

Samples of refined soybean oil were irradiated with lights from a 20-watt incandescent tungsten lamp, a 20-watt fluorescent daylight type lamp, a 20-watt low-pressure mercury vapor germicidal lamp, and direct sunlight for an experimental period of 147 days. Some samples were stored in a dark room throughout the period as a control. The peroxide values of all samples were measured every week. The induction period of the samples was arbitrarily taken as the time required for the samples to reach a peroxide value of 15. The induction period of the control was estimated at 198 days. Those of the samples irradiated with the incandescent light, the fluorescent light, the ultraviolet light, and the sunlight were estimated at 196, 119, 52 and 6 days, respectively. The sunlight showed by far the strongest prooxidant activity whereas the incandescent light showed the weakest but distinct prooxidant activity. The small temperature differences observed among the various samples throughout the experimental period did not seem to affect the oxidation rates of the irradiated samples in any significant way.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.400-406
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• 2010

Etiolation of plant leaves evoke to be photosynthetically inactive because plant leaves are unable to convert photochlorophyllide to chlorophyllide in the absence of light. In addition, UV-B radiation plays an important role in photomorphogenesis and excessive UV-B radiation decreases photosynthesis and causes to damage to cellular DNA. In the present study, two electrical lights obtained with the ultraviolet lamp and moderate lamp were employed to young plants soybean (Glycine max Merr. var Seoritae). After treatment of different lights, young plants were harvested for the determination of pigment contents and chlorophyll fluorescence. The contents of carotenoids and anthocyanins were significantly enhanced with the excessive UV-B radiation. Excessive UV-B light reduced dramatically photosynthetic efficiency causing an irreversible damage on PSII in comparison to the controls treated under normal illumination. As the treatment of normal illumination after dark treatment, the contents of carotenoids and anthocyanains were not changed in the leaves and photosynthetic ability were retained. Therefore, Seoritae soybean leaves might protect themselves from excessive UV-B radiation with up-regulation of antioxidants.

• Fisheries and Aquatic Sciences
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• v.16 no.1
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• pp.35-39
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• 2013

The aim of this study was to assess visible implant fluorescent elastomer (VIE) tagging in greenling Hexagrammos otakii. The experiental fish were anesthetized individually and marked with orange, yellow, red, and green elastomer at the following five body locations, respectively: the adipose eyelid, the surface of the dorsal fin base, the inside surface of the pectoral fin base, the inside surface of the pelvic fin base, and the surface of the anal fin base. Control fish were anesthetized but not marked. During the 20-month trial, fish growth and retention, underwater visibility, and readability of the tags were determined. After 20 months, body length of marked greenling ($43.2{\pm}3.5cm$, mean ${\pm}$ standard deviation [SD]) did not differ from that of the control ($41.4{\pm}3.7cm$). Additionally, the body weight of marked greenling ($527.4{\pm}39.8g$, mean ${\pm}$ SD) did not differ from that of the controls ($505.9{\pm}31.7g$). Greenling retained >90% of the tags at the surface of the dorsal fin base. The anal fin base showed a higher tag retention rate than the inside surfaces of the pectoral fin and the pelvic fin bases (P < 0.05). Red and orange tags were identified more easily underwater than green and yellow tags. Green and yellow tags emitted fluorescence in response to a narrower range of light wavelengths. Thus, the VIE mark was easy to apply to greenling (< 1 min per fish) and was readily visible when viewed under an ultraviolet lamp.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.207-207
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• 2008

ZnO is one of the widely utilized n-type semiconducting oxide materials in the field of optoelectronic devices. For its application to the fabrication of promising ultraviolet (UV) photodetectors, ZnO with various structures has been extensively studied. However, study on the photodetectors using zero-dimensional (0-D) ZnO nanoparticle is scarce while the 0-D nanoparticle structure has many advantages compared to the other dimensional structures for absorption of light. In this study, the photocurrent characteristics of ZnO nanoparticles were investigated through a simply pasting of the nanoparticles across the pre-patterned electrodes. Then the photoluminescence (PL) characteristic, photocurrent response spectrum, photo- and dark-current and photoresponse spectrum were investigated with a He-Cd laser and an Xe lamp. An dominant PL peak of the ZnO nanoparticles was located at the wavelength of 380 nm under the illumination of 325-nm wavelength light. The ratio of photocurrent to dark current (on/off ratio) is as high as 106 which is considerable value for promising photodetectors. On the other hand, the time constants in photoresponse were relatively slow. The reasons of the high on/off ratio and relatively slow photoresponse characteristic will be discussed.

• Textile Coloration and Finishing
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• v.25 no.3
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• pp.172-180
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• 2013

Aramid fibers are being used increasingly in a wide range of application due to low density, high specific strength, high modulus, and high thermal resistance. But owing to its special physical and chemical structures, it is sensitive to absorb the ultraviolet light which will degrade the fiber's useful mechanical properties and structure. In this paper, the sol-gel technique was used to improve the photo-stability of p-aramid fibers. $TiO_2$, modified $SiO_2$/$TiO_2$ sol were used as coating solutions. The influence of the such coatings on the photo-stability of p-aramid fiber was investigated by an accelerated photo-ageing method using xenon lamp. The photo-stability of p-aramid fiber showed obvious improvement after the modified silica binding coating. But the amorphous $TiO_2$ sol coatings showed a negative effect. After 144h light exposure, the modified silane binder-coated fibers showed less degradation in mechanical properties with the retained tensile strength greater than about 70% of the original value.

• Food Engineering Progress
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• v.15 no.1
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• pp.28-33
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• 2011

UV-C and -B types of lamps, and $H_2O_2$ as a photocatalytic material were applied to optimize processing conditions for pesticides removal in Mandarine orange peel. Factors to affect the removal of pestrcides were arranged as a function of irradiation temperature, irradiation time, and $H_2O_2$ spray concentration. The optimum processing conditions for the chloropyrifos and the EPN removals in Mandarine orange peel were irradiation time of 60 min, irradiation temperature of $45^{\circ}C$ and $H_2O_2$ spray concentration of 1000 ppm. However, the optimum processing conditions for methidathion removal were 60 min of irradiation time, $40^{\circ}C$ of irradiation temperature and 1000 ppm of $H_2O_2$ spray concentration. The residual percentages of chloropyrifos, EPN and methidathion were 46, 49 and 28% after above irradiation processing, respectively.

• Nano
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• v.13 no.10
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• pp.1850118.1-1850118.17
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• 2018

Nanoparticles of the semiconductor catalyst $Cd_xZn_{1-x}S$ were embedded into the metal organic framework MIL-101(Cr) to obtain $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites. These materials not only possess high surface areas and mesopores but also show good utilization of light energy. The ultraviolet-visible diffuse reflectance patterns of $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites showed that $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) possessed good visible light response ability among the synthesized nanocomposites. The photocatalytic performance of the $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites were tested via degradation and mineralization of methylene blue in neutral water solution under light irradiation using a 300W xenon lamp. As a result, using $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) as a catalyst, 99.2% of methylene blue was mineralized within 30 min. Due to the synergistic effect of adsorption by the MIL-101(Cr) component and photocatalytic degradation provided by the $Cd_{0.8}Zn_{0.2}S$ component, the $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) catalyst displayed superior photocatalytic performance relative to $Cd_{0.8}Zn_{0.2}S$ and MIL-101(Cr). Furthermore, $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) possessed excellent stability during photodegradation and exhibited good reusability. The remarkable photocatalytic performance of $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) is likely due to the effective transfer of electrons and holes at the heterojunction interfaces.