• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.5 s.164
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• pp.659-669
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• 2007

The purpose of this study was to investigate the degradation of silk fabrics dyed with gardenia and sappanwood by Ultraviolet Light(UV). To asses the effect of uv on dyed silk fabrics, physical and chemical properties of samples were explored. K/S value rapidly decreased with increasing exposure time. Mordanting improved ultraviolet-cut ability and the sappanwood dyed samples were superior to those of gardenia dyed in ultraviolet-cut ability. Color progressively faded away as uv exposure time increased, accordingly, $L^*,\;a^*,\;b^*$, H/VC, ${\Delta}E$ were changed. Morphological change observed with SEM represented degradation of silk fabrics from the outer fibril to the inner fibril. Tensile Strength abruptly decreased as uv exposure time increased and the mordanted samples showed higher tensile strength than the unmordanted. FT-IR analysis confirmed that main peaks at 3297 and $1704cm^{-1}$ band for silk fabric were due to N-H and C=O stretching, gardenia peaks at 1654 and $668cm^{-1}$ band representing C=O(ester), C=C(alken) and O-C=O(carboxylic acids) of crocin and sappanwood peaks at $1715cm^{-1}$ band representing C=O(cyclic keton) of brazilin appeared on the samples exposed for 14 days, but these peaks indicating colorants after 28 days of uv exposure faded away due to prolonged exposure of uv.

• Food Science of Animal Resources
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• v.44 no.2
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• pp.372-389
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• 2024

This study investigated the efficacy of ultraviolet-C (UV-C) irradiation in enhancing the quality of raw bovine milk by targeting microbial populations and lipid peroxidation, both of which are key factors in milk spoilage. We categorized the raw milk samples into three groups based on initial bacterial load: low (<3 Log 10 CFU/mL), medium (3-4 Log 10 CFU/mL), and high (>4 Log 10 CFU/mL). Using a 144 W thin-film UV-C reactor, we treated the milk with a flow rate of 3 L/min. We measured the bacterial count including standard plate count, coliform count, coagulase-negative staphylococci count, and lactic acid bacteria count and lipid peroxidation (via thiobarbituric acid reactive substances assay) pre- and post-treatment. Our results show that UV-C treatment significantly reduced bacterial counts, with the most notable reductions observed in high and medium initial load samples (>4 and 3-4 Log 10 CFU/mL, respectively). The treatment was particularly effective against coliforms, showing higher reduction efficiency compared to coagulase-negative staphylococci and lactic acid bacteria. Notably, lipid peroxidation in UV-C treated milk was significantly lower than in pasteurized or untreated milk, even after 72 hours. These findings demonstrate the potential of UV-C irradiation as a pre-treatment method for raw milk, offering substantial reduction in microbial content and prevention of lipid peroxidation, thereby enhancing milk quality.

• Journal of the Society of Disaster Information
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• v.17 no.2
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• pp.195-205
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• 2021

Purpose: The ultraviolet reflectance and transmittance of coastal building materials are one of the important factors of ultraviolet radiation in and out of coastal building. In this research, the ultraviolet spectral reflectance of many kinds of building materials was measured. Also, the relationships with the lightness, roughness, and chromaticity, which are surface characteristics, were reviewed and suggested. Method: In this study, according to the CIE classification, the ultraviolet region was defined as short-wavelength region UV-C(10nm~280nm), medium-wavelength region UV-B (280-315 nm), and long-wavelength region UV-A (315-400nm), and the visible light region was defined as (400nm~780nm). Spectrophotometer was used to continuously measure the reflectance from the ultraviolet region to the visible light region. Results: From the measurement results, the ultraviolet reflectance on Wood was shown to be about Visible 55-68%, UV-A^* 7-12%, and UV-B 4-5%. Wall tiles are about Visible18-40%, UV-A^* 8-20%, and UV-B^* 7-8%. That on concrete was shown to be about Visible 37%, UV-A^* 28%, and UV-B^*19%. Conclusion: The ultraviolet reflectance can be estimated by visible reflectance. Also, it is important to select a variety of materials according to the application when blocking UV.

• Journal of Conservation Science
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• v.27 no.2
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• pp.191-199
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• 2011

A study was done to compare the properties of artificially deteriorated silk with ultraviolets for reinforcing of loss area of paintings on silk. Deteriorated surface of raw silk irradiated by long-wavelength ultraviolet(UV-A) than short-wavelength ultraviolet(UV-C) was similar to naturally aged raw silk. UV-A irradiation raw silk was slowly decreased in tensile tenacity and elongation and lowered in yellowness index than that of UV-C. Water content of UV-A irradiation raw silk than that of UV-C was higher. UV-A irradiation raw silk had no problem in dyeing and inpainting for conservation because of low yellowness index. UV-C irradiation raw silk was brittle, but UV-A irradiation raw silk was seemed to tough and similar to naturally aged raw silk. Korean painting conservator estimated that UV-A irradiation raw silk was more proper for reinforcing of loss area of paintings on silk than that of UV-C.

• Journal of Bio-Environment Control
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• v.16 no.2
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• pp.96-100
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• 2007

There was no difference in total light transmissivity of covering materials. But the light transmittance of J-2 in greenhouse was by 78.25 which was higher than any other film. The high light transmittance of J-2 was come from low water condensation and dust attached in film surface. The ultraviolet light of J-3 was completely intercepted. The ultraviolet transmittance rate of others was from 62 to 76%. In no heating oriental melon cultivation, the air temperature in tunnel was 15 to $21^{\circ}C$ higher than outer, and the soil temperature in tunnel was 20 to $25^{\circ}C$ higher than outer. Air temperature and soil temperature of J-2 were higher than any other film.

• Journal of Sensor Science and Technology
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• v.14 no.5
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• pp.362-367
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• 2005

ZnO films were deposited on MgO substrates (ZnO/MgO) by ultrasonic spray pyrolysis. Substrate temperature varied from $250^{\circ}C$ to $350^{\circ}C$. The crystallographic properties and surface morphologies of the ZnO/MgO films were studied by X-ray diffraction and scanning electron microscopy. The properties of photoluminescence (PL) for the films were investigated by dependence of PL spectra on the substrate temperature and the annealing temperature. The ZnO/MgO films prepared at $350^{\circ}C$ showed the strongest Ultraviolet light emission peak at 18 K and 300 K among the films in this study. The annealing process increases the visible light emission, which is due to the increased oxygen vacancies.

• Journal of Sensor Science and Technology
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• v.18 no.4
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• pp.316-321
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• 2009

Er-doped ZnO(ZnO:Er) films were deposited onto MgO wafers by ultrasonic spray pyrolysis at 550 $^{\circ}C$ varying the concentration of Er in the deposition source from 0.5 wt% to 3.0 wt%. Annealing of the films in a vacuum was carried out to increase the intensity of ultraviolet(UV) emission from the films. The annealing temperature was between 600$^{\circ}C$ and 800$^{\circ}C$. The crystallographic properties and surface morphology of the films were investigated by X-ray diffraction(XRD)and scanning electron microscope(SEM), respectively. The properties of photoluminescence(PL) for the films were investigated by the dependence of PL spectra on the annealing temperature. X-ray photoelectron spectroscopy(XPS) was conducted to find the composition change in the films by the annealing.

• Journal of the Korean Home Economics Association
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• v.40 no.10
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• pp.77-85
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• 2002

This study was conducted to evaluate the efficiency of various fabrics in protecting from solar radiation and ultraviolet radiation(UV). Six kinds of fabrics were selected and examined in singles or doubles. It was studied how the materials and the thickness of air layer between the fabric and the floor affected the protection efficiency of fabrics from sunlight. The results were as followes; 1) Protection from solar radiation: In the case of over 2 cm air layer, doubled fabric composed of aluminum coating-nylon and white or black polyester/cotton(T/C) was the most protective(p<0.001). In the case of 0 cm air layer, the case without fabric and white T/C were more effective(p<0.001). And the thicker the air layer the more effective the protection. 2) Protection from UV : Doubled fabric composed of aluminum coating-nylon and black T/C was the most protective(p<0.001) and the thinner the air layer the more effective the protection(p<0.001).

• Journal of the Korean Society of Food Culture
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• v.16 no.5
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• pp.463-469
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• 2001

This study was to investigate the effect of ultraviolet rays, soaking, boiling and baking to ergocalciferol ($Vit.D_2$) and riboflavin($Vit.B_2$) contents of mushrooms, Lentinus edodes, Pleurotus ostreatus and Agaricus bisporus. The results were as follow: 1. Mushrooms were exposed to ultraviolet rays Lentinus edodes : $10J/cm^2$, Pleurotus ostratus : $2J/cm^2$ and Agaricus bisporus : $2J/cm^2$. 2. Before exposing to ultraviolet rays, the ergocalciferol contents of mushrooms were all $0{\mu}g/g$ dry base, but after exposing to it , those of Lentinus edodes, Pleurotus ostreatus and Agaricus bisporus were $222.50{\pm}5.30{\mu}g/g$ dry base, $150.90{\pm}6.60{\mu}g/g$ dry base and $23.98{\pm}1.20{\mu}g/g$ dry base, respectively 3. Before and after exposing to ultraviolet rays, the riboflavin contents of Lentinus edoes, Pleurotus ostreatus and Agaricus bisporus were $18.22{\pm}0.71{\mu}g/g$ dry base and $11.72{\pm}0.50{\mu}g/g$ dry base, $4.57{\pm}0.20{\mu}g/g$ dery base and $3.26{\pm}0.15{\mu}g/g$ dry base, and $37.42{\pm}1.20{\mu}g/g$ dry base and $27.33{\pm}2.10{\mu}g/g$ dry base, respectively. 4. The ergocalciferol contents of mushrooms according to boiling time were not significantly different but the riboflavin contents of them were decreased according to the increase of boiling time. 5. The ergocalciferol and riboflavin contents of mushrooms were decreased according to the increase of NaCl concentration and baking temperature. 6. The ergocalciferol content of Lentinus edodes after a short time soaking at $80^{\circ}C$ was higher than a long time soaking at $20^{\circ}C,\;40^{\circ}C$ and $60^{\circ}C$.

• The Bulletin of The Korean Astronomical Society
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• v.34 no.2
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• pp.31.1-31.1
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• 2009