• Preventive Nutrition and Food Science
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• 제14권4호
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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.

• 한국환경과학회지
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• 제15권7호
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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.

• 한국산학기술학회논문지
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• 제7권6호
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• pp.1296-1301
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• 2006

눈은 자외선과 가시광선에 노출되어 있다. 눈은 자외선 노출에 해로우므로 모든 자외선으로부터 눈을 보호해야 한다. 본 연구에서는 자외선 차단을 위해 투명 플라스틱에 유-무기 하이브리드 재료와 자외선 흡수제의 배합에 의한 자외선 차단 코팅하였고, PMMA, CR 39 및 PC기재에 적용하여 자외선 차단 효과를 조사하였다. 자외선 흡수제의 양이 증가할수록 자외선의 투과도는 낮았다. PMMA의 경우 자외선 투과도를 현저히 감소시켰으며 CR 39에서도 자외선 차단 효과가 있는 것으로 나타났다. 한편, PC자체에서는 자외선 차단효과가 있는 것으로 평가되었다. CR 39 렌즈의 부착력, 내약품성, 내온수성은 우수하였고, 연필 경도의 경우 4H였으며 내마모성은 좋지 않았다.

• Journal of Astronomy and Space Sciences
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• 제13권1호
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• pp.72-78
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• 1996

복잡한 광도변화를 보이는 RS CVn형 단주기 식쌓성 UV Piscium의 BV 광도곡선을 Wilson-Devinney의 차등보정 방법으로 분석하여 궤도요소들을 산출하였다. 우리가 분석에 사용한 광도곡선은 식이 일어나지 않고 있는 부분에서도 심한 광도변화를 보이고 있는데 이는주성에 흑점 군이 있기때문인 것으로 가정하고 이 흑점군의 위치와 크기 등도 계산하였다. 그 결과 UV Psc는 분리계쌍성이며 주성이 반성에 비하여 질량도 크고 온도도 높으나 반경은 거의 같다는 것을 알았다. 이것은 일반적인 항성 모형과는 대조를 보이는 것이어서 이를 검증하기 위한 관측이 요구된다.

• 분석과학
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• 제24권6호
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• pp.493-502
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• 2011

본 연구에서는 가시광촉매의 특성을 나타낼 수 있는 촉매를 제조하여 촉매를 특성화 하였으며, toluene, xylene, MEK (methyl ethyl ketone), ammonia를 반응물로 하여 기존의 UV-광촉매와 분해능을 비교 실험하였다. UV-광촉매는 파장범위가 280~360 nm 근처에서 광촉매가 활성화된다. 그러나 가시광촉매는 가시광영역인 400~750 nm의 파장영역에서도 광촉매가 활성화 된다. 이것을 UV-Vis 흡수도로 파악하였다. 그리고 가시광촉매의 성능을 향상시키기 위하여 여러 가지 재료로 도핑하는데, 여기서는 망간에 Pt를 부가하여 성능향상을 꾀하였다. Pt를 첨가한 가시광 촉매의 경우 성능이 향상되었음을 알 수 있었다. 그리고 바인더로 MTMS (methyl tri methoxy silane)를 사용하였으며 바인더양에 따른 접촉각을 측정하였다. MTMS 함량이 증가할수록 접촉각이 커졌다. 따라서 친수성이 줄어든 것으로 나타났다. 그리고 Mn-$TiO_2$ 촉매의 항균성이 매우 우수한 것으로 나타났다.

• Journal of Plant Biotechnology
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• 제1권2호
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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.

• 한국물환경학회지
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• 제25권4호
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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.

• 대한수의학회지
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• 제42권3호
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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.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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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.

• 스마트미디어저널
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• 제11권9호
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• pp.21-29
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• 2022

센서 및 분석 경화시장에서 폭넓게 사용되고 있는 기존의 UV 광원들이 점차 LED로 교체 적용되고 있다. 그러나 UV LED의 광 성능이 기존 램프에 비하여 여전히 낮고 광 효율성도 낮아 효능성 감소 및 수명 저하 문제가 존재한다. 현재 환경과 UV램프의 기술적인 문제로 인하여 점차 LED교체가 이루어지고 있는 시점에서 UV LED의 성능 향상이 매우 중요하다. 본 연구에서는 UV LED의 수명 증가 및 성능 향상을 위한 new package 설계 및 분석을 실행하였다. 광소자에서 발생하는 열을 직접 방출하기 쉽도록 방열특성이 우수한 packaging 설계가 매우 중요한데, 본 연구에서는 열적 안전성을 기반으로 안정성이 우수한 패키지 구성 및 UV LED용 new packaging을 설계 구현하였다. 이를 통하여 광 효율 및 방열성능 향상을 위한 새로운 UV LED용 new packaging을 구성하고 전기적 광학적 특성을 각각 분석하였다. 또한 UV LED package의 방열성능 향상을 위해 높은 반사율 특성을 가지는 알루미늄(Al)를 이용, 최적의 렌즈 포커싱를 적용함으로서 광출력 효율을 증가 시킬 수 있었다. 기존 은(Ag)대비 광효율 결과가 약 ~30%이상 개선되었으며, 새로 적용된 광소자 패키지에서 광출력 저하 특성이 약 10% 이상 향상됨을 확인 할 수 있었다.