• Title/Summary/Keyword: UV light

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Effects of Package Materials on Quality Change of Pine Bud Beverage Under Ultraviolet Light

  • An, Duek-Jun
    • Preventive Nutrition and Food Science
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    • v.14 no.4
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    • pp.349-353
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    • 2009
  • The effects of packaging materials on preserving the functional component of pine bud beverage stored under UV (ultraviolet) light exposure conditions were studied. The order of UV light blocking properties of the selected packages was: opaque can> opaque PET (polyethylene terepthalate) with green lamination=transparent PET with 10% PEN (polyethylene naphthalate) blending> transparent PET, and did not depend on film thickness in specified range. At 20${^{\circ}C}$, the order of preserving degree of original color and endobornyl acetate, which is quality index of pine bud beverage, was the same as above. Exposure to UV light can cause of deterioration of functional food components, but green color lamination and blending of PEN materials with transparent PET help to preserve the UV sensitive pine bud beverage components. However, the treated PET bottles have poorer preservation capabilities than the opaque cans. Transparent PET with PEN blending, in particular, will be very useful packaging material for colorful functional beverage preservation by helping to protect the ingredients while attracting consumer attention.

Disinfection Characteristic of Sewage Wastewater Treatment Using Solar Light/TiO2 Film System (태양광/광촉매를 이용한 오폐수 살균특성)

  • Cho Il-Hyoung;Lee Nae-Hyun;An Sang-Woo;Kim Young-Kyu;Lee Seung-Mok
    • Journal of Environmental Science International
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    • v.15 no.7
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    • pp.677-688
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    • 2006
  • Currently, the application of $TiO_2$ photocatalyst has been focused on purification and treatment of wastewater. However, the use of conventional $TiO_2$ slurry photocatalyst results in disadvantage of stirring during the reaction and of separation after the reaction. And the usage of artificial UV lamp has made the cost of photocatalyst treatment system high. Consequently, we studied that solar light/$TiO_2$ film system was designed and developed in order to examine disinfection characteristics of sewage wastewater treatment. The optimum conditions for disinfection such as solar light intensity, characteristic of sewage wastewater, amounts of $TiO_2$ and comparison of solar ligth/$TiO_2$ systems with UV light/$TiO_2$ system was examined. The results are as follows: (1) photocatalytic disinfection process with solar light in the presence of $TiO_2$ film more effectively killed total coliform (TC) than solar light or $TiO_2$ film absorption only. (2) The survival ratio of TC and residual ratio of organic material (BOD, CODcr) decreased with remain resistant material. (3) The survival ratio of TC and residual ratio of organic material (BOD, CODcr) decreased with the increase of amounts of $TiO_2$. (4) TC survival ratio decreased linearly with increasing UV light intensity. (5) The disinfection effect of solar light/$TiO_2$ slurry system decreased more than UV light/$TiO_2$ film systems. (6) The disinfection reaction followed first-order kinetics. We suggest that solar light instead of using artificial UV light was conducted to investigate the applicability of alternative energy source in the disinfection of TC and the degradation of organic material.

UV Blocking Coatings by Combination of Organic-inorganic Hybrid Materials and UV absorbers (유-무기 하이브리드 재료와 자외선 흡수제의 배합에 의한 자외선 차단 코팅)

  • Yu, Dong-Sik;Lee, Ji-Ho;Ha, Jin-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.6
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    • pp.1296-1301
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    • 2006
  • The human eye is exposed to UV and visible light. UV light exposure becomes harmful to the eye. Protection for eyes should block all ultraviolet rays. In our study, organic-inorganic hybrid materials have been applied to UV blocking coatings with UV absorbing materials on transparent plastics. The optical properties of UV blocking coatings were investigated in PMMA, CR 39 and PC substrates. In case of all UV absorbers, the transmission of UV light decreases with an increased amount of absorber. Our findings indicate that PMMA significantly reduced the transmission of UV radiation, CR 39 showed moderate decrease, while UV-uncoated PC had some UV blocking properties. Adhesion, hot water resistance and chemical resistance of the UV-coated CR 39 lenses were good. Pencil hardness were 4H. Abrasion resistance were poor.

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OBITAL ELEMENT ANALYSIS OF A SHORT PERIOD ECLIPSING BINARY UV PISCIUM (단주기 식쌍성 UV PISCIUM의 궤도요소 연구)

  • 한원용;김호일;이우백
    • Journal of Astronomy and Space Sciences
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    • v.13 no.1
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    • pp.72-78
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    • 1996
  • We evaluated the orbital elements of BV light curves of a short period RS CVn type eclipsing binary system UV Picsium that shows complication light variation, by analyzing with the Winson-Devinney's differential correction method. Because the analyzed light curves shows large light variation at outside eclipse region, we assumed spotted region of the primary component and calculated its position and size. The results show the UV Psc is a detached binary system of nearly the same radii and the primary component has high mass with high temperature. However this result is not consistant with customary stellar models, thus requires more observational data to confirm this problem.

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The characteristics of Mn-TiO2 catalyst for visible-light photocatalyst (Mn-TiO2 촉매의 가시광촉매 특성)

  • Kim, Moon-Chan
    • Analytical Science and Technology
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    • v.24 no.6
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    • pp.493-502
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    • 2011
  • The catalyst works for visible-light region was characterized. Toluene, xylene, MEK and ammonia were used as reactants. The decomposition efficiency was compared between visible-light photocatalyst and UV-light one. UV-photocatalyst can be activated with UV-light wave length of 280~360 nm. However, visible-light photocatalyst can be activated with visible wave length of 400~750 nm. This result was found by using UV-Vis absorbance. A lot of materials were doped to visible light photocatalyst in order to increase its performance. Platinum was added to visible light photocatalyst with manganese in order to increase performance of the visible light photocatalyst. MTMS (Methyl tri methoxy silane) was used as a binder. Contact angle was analyzed varying with amount of binder. Contact angle was increased with increasing the amount of MTMS. As a result, the hydrophilic property of photocatalyst with MTMS binder was decreased due to its hydrophobic one. And Mn-$TiO_2$ catalyst had an excellent anti-bacterial property.

Enhanced Anthocyanin Accumulation by UV-B and JA Treatment in Cell Suspension Culture System of Grope (Vitis vinifera L.)

  • Won yong Song;In, Jun-Gyo;Lim, Yong-Pyo;Park, Kwan-Sam
    • Journal of Plant Biotechnology
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    • v.1 no.2
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    • pp.117-121
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    • 1999
  • Effects of jasmonic acid treatment, UV-B and white light treatment on the anthocyanin biosynthesis and cell growth were investigated using the cell suspension culture system of grape (Vitis vinifera L.). Cell growth was not affected by white light irradiation, while it was remarkably suppressed by UV-B irradiation from 8 to 32 h. Anthocyanin accumulation dramatically increased after 16 h from irradiation of UV-B. Simultaneous treatment of jasmonic acid and UV-B increased anthocyanin accumulation by 10-fold. The cell division was restored when anthocyanin was abundantly accumulated after 32 h from UV-B irradiation. Optimum concentration of jasmonic acid was found to be 5 uM for maximum accumulation of anthocyanin. Application of jasmonic acid to grape suspension cells rapidly induced the expression of CHS gene after 2 h from treatment and showed maximum level at 32 h. Simultaneous treatment of jasmonic acid and light also induced CHS gene expression after 2 h, but the maximum level of CHS transcript was observed at 16 h with white light and 8 h with UV-B exposure. The synergistical effects could be explained by the defense mechanism that UV irradiation is mediated in part by alterations in JA and its signaling pathway.

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A Study on Optimal Design of UV Contactor using an Optical Radiation Model (광학모델을 이용한 자외선 접촉조 최적 설계에 관한 연구)

  • Choi, Younggyun;Kim, Dooil;Kim, Sunghong
    • Journal of Korean Society on Water Environment
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    • v.25 no.4
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    • pp.547-552
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    • 2009
  • Because of refractory property of light, the travel path of UV light becomes longer than the straight line and shorter solely in water as UV light passes sequentially through air, quartz and water. Note that water significantly absorbs UV light. Hence, UV intensity shall be estimated to be lower when refraction is neglected than it is considered. Reflection is also critical for the design of UV radiation system. While the reflection at the interface of air and quartz is low enough to ignore, it is too high to be ignored at the interface of quartz and water. Assuming constant power, smaller length to width ratio of UV reactor is beneficial and single-lamp system is preferred to multi-lamps. Under the given cross section, optimal lamp positions could be decided. For example of an elliptical reactor with dual lamps, the optimal lamp locations shall be the 1/3 and 2/3 position of the longer axis.

Involvement of Nitric Oxide and Prostanoid on Photorelaxation in Pig Renal Artery (UV-light 에 의한 혈관 이완작용에 있어서 nitric oxide와 prostanoid의 관련성)

  • Kim, Joo-Heon;Shim, Cheol-Soo;Jeon, Seok-Cheol
    • Korean Journal of Veterinary Research
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    • v.42 no.3
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    • pp.321-326
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    • 2002
  • The effect of nitric oxide synthase(NOS) inhibita, $N^G$-nitro-L-arginine-methyl ester(L-NAME) and prostanoid synthesis inhibiter, indomethacin on the photorelaxation, when was exposed to the long-wave length UV-light, was examined on the precontraction by the phenylephrine in the isolated pig renal artery. 1. UV-light relaxed both with-endothelium and without-endothelium in the pig renal arterial ring contracted by the phenylephrine. The magnitude of photorelaxation was dependent on the exposure time for UV-light. 2. UV-Iight induced relaxation was inhibited by L-NAME and indomethacin on the precontraction by the phenylephrine in the isolated pig renal artery. 3. UV-Iight induced relaxation was inhibited by methylene blue on the precontraction by the phenylephrine in the isolated pig renal artery. These results suggest that UV-light induced photorelaxation may be due to cGMP involved both nitric oxide and prostanoid on the precontraction by the phenylephrine in the isolated pig renal artery.

Studies about Visible Light Distribution in PDP Cells with 3-dimesional Optical Code

  • Eom, Chul-Whan;Kang, Jung-Won
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.582-584
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    • 2007
  • In order to improve the accuracy of simulated results, new UV source was designed. Previously the optical simulation was performed with the symmetric planar UV source. To design new UV source, UV distribution from the plasma fluid code was implanted to the 3-dimensional optical code to generate the visible light distribution. The results from planar UV source and new UV source were compared with the ICCD (Intensified CCD) image in real PDP cell and analyzed the variation of geometries and optical properties.

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Implementation of Electrical and Optical characteristics based on new packaging in UV LED (UV LED의 광효율 및 방열성능 향상을 위한 new packaging 특성 연구)

  • Kim, Byoung Chol;Park, Byeong Seon;Kim, Hyeong-Jin;Kim, Yong-Kab
    • Smart Media Journal
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    • v.11 no.9
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    • pp.21-29
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    • 2022
  • Ultra Violet(UV) is gradually being replaced with LED instead of general UV lamps. However, the light efficiency of UV LED is still lower than that of the general lamp, and the light efficiency is also low. Due to the current environment and technical problems of UV lamps, the LED replacements are gradually being made. In this study, a new package design and analysis were performed to increase the lifetime and performance of UV LEDs. A new packaging for UV LED were designed and implemented. The new packaging for UV LED was constructed to improve light efficiency. And the electrical and optical characteristics were analyzed respectively. To improve the optical efficiency in UV LED package, the Al has been used based on high reflectivity and applying the optimal lens focusing. Compared to the existing silver Ag, the light efficiency was improved by about 30% or more, and it was confirmed that the light output degradation characteristic was improved by about 10% in the newly applied optical device chip.