• 한국습지학회지
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• 제9권1호
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• pp.99-105
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• 2007

Nonylphenol polyetoxylates (NPnEOs) metabolites; nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), nonylphenoxyacetic acid (NPEC) (collectively referred to "NPE-c") were examined for their degradations by using of lab-scale UV/photocatalytic silicagel (ultraviolet photocatalytic degradation in the presence of silicagel coated with titanium dioxide as a catalyst) reactor. NPE-c degradations by UV/photocatalytic silicagel treatment reached approximately 85-93 % after 40 min irradiation independently of its initial concentration (between ca. 0.5 and 2.0mg/l). Any intermediates under the NPE-c degradation were not identified by GC/MS sample analysis. Degradations of NPE-c were followed pseudo first-order kinetics. Then, the effectiveness of UV/photocatalytic silicagel treatment for degradation of NPE-c was in the order of NPEC > NP > NP1EO.

• 생명과학회지
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• 제27권9호
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• pp.975-985
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• 2017

UV 조사에 의해 유도된 광노화(photoaging)에 대한 한천젤마스크(agar gel mask, AGM)의 효과를 평가하기 위해, SKH-1 hairless 마우스의 피부에 4주간의 UV조사와 AGM 및 에센스처리 한천젤마스크(agar gel mask dipped in essence, AGMdE)를 동시에 처리한 후 피부주름, 피부표현형, 피부조직구조, 항산화조건 및 독성 등을 분석하였다. AGM과 AGMdE의 부착은 주름형성의 억제, 홍반지수의 감소, 피부수분의 증진뿐만 아니라 경피 수분손실(TEWL)을 방지하였다. 또한, 표피두께는 UV+Vehicle 처리군과 비교했을 때, UV+AGM 및 UV+AGMdE 처리군에서 UV를 조사하지 않은 그룹과 유사한 수준으로 회복되었다. MMP-1과 tyrosinase의 발현수준은 UV+Vehicle 처리군에서 가장 높게 증가하였으나 UV+AGM 및 UV+AGMdE 처리군에서 유의적으로 감소하였다. 더불어, SOD 활성은 UV+Vehicle 처리군에 비하여 UV+AGM 및 UV+AGMdE 처리군에서 유의적으로 감소되었지만, 대부분의 독성화합물 처리에 의해 유도되는 혈청생화학적 지표와 조직학적 특성의 변화는 UV+AGM 및 UV+AGMdE 처리군에서 관찰되지 않았다. 따라서, 이러한 결과들은 AGM이 피부형태, 조직학적 구조, 산화적 상태를 조절함으로써 피부노화를 예방하는 마스크팩으로 활용될 수 있는 가능성을 있음을 제시한다.

• 패션비즈니스
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• 제11권6호
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• pp.52-61
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• 2007

To increase the ultraviolet radiation (UVR) protection of cotton fabric, ultraviolet protection (UVP) materials were treated onto cotton fabric using a new technique, UV-curing. A photocrosslinkablepolymer, poly(ethylene glycol) dimethacrylate was used as a UV-curable resin in the presence of a small amount of photoinitiator. Two kinds of UVP materials were used, UV-absorber, 2,2'-dihydroxy-4-methoxy benzophenone, and UV-scatterer, $TiO_2/ZnO$ Pad-dry-cure method in employing these materials onto cotton was also conducted to compare the effectiveness and the washfastness of UVP treatment between curing methods. UVP treated cotton fabric showed a moderate increase in UVP in case of 2,2'-dihydroxy-4-methoxy benzophenone treatment and a high increase in case of $TiO_2/ZnO$. UV-curing method increased the washfastness of UVP property of $TiO_2/ZnO$ treated cotton fabrics. However, in case of 2,2'-dihydroxy-4-methoxy benzophenone, similar wash fastnesses of UV-cured and pad-dry-cured cotton were observed. It can be presumed that 2,2'-dihydroxy-4-methoxy benzophenone was not significantly affected by water since its hydrophobicity. In short, UV-curing of UVP materials onto cotton was successfully done, and treated cotton fabrics showed the increased UVP properties and an increased washfastness in some extent.

• 한국유체기계학회 논문집
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• 제18권2호
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• pp.54-59
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• 2015

The performance of UV reactor which is used in water treatment is strongly affected by UV fluence rate and water flow in the UV reactor. Therefore, CFD tools are widely used in designing process of UV reactors. This paper describes the development of a computational fluid dynamics (CFD) methodology that can be used to calculate the performance of open channel type UV reactor used in wastewater treatment plant. All computations were performed using commercial CFD code, CFX, by considering three dimensional, steady, incompressible flow. The Eulerian-Eulerian multi-phase method were used to capture the water-air interface. The MSSS model, provided by UVCalc3D, was used to calculate the UV intensity field. The numerical predictions and calculated UV Dose were compared with experimental dataset to validate the CFD methodology. The reactor performance based on MS2 log reduction was well matched with measurements within 6%.

• 상하수도학회지
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• 제22권4호
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• pp.421-427
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• 2008

UV disinfection is widely used in water treatment facilities and wastewater treatment plant because of its effectiveness to removal of pathogen and Giardia which is resistant to traditional chemical disinfection. As a design and performance tool of UV disinfection system, 3 dimensional UV intensity models were composed and simulated to compare each other and to find affecting factors in this study. Reflection, refraction and absorption are important parameters in UV intensity model and MPSS and MSSS model can reflect these parameters while LSI model can not. Absorption is the most important parameters among the reflection, refraction, absorption and shadowing so, this should not be neglect. Based on this simulation, shadowing effect is negligible when the number of installed lamp is a few but, this effect can not be neglectable when the number of installed lamp is quite a few. The errors according to shadowing effect is increased as the number of lamp installed increased.

• Journal of the Korean Wood Science and Technology
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• 제32권6호
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• pp.23-35
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• 2004

The goal of study was to investigate the influence of the acrylated urethane oligomer on mechanical properties, the chemical resistance and thermal resistance of the UV curable urethane acrylate coatings for fancy veneer overlayed plywood flooring. The pencil hardness and abrasion resistance of the coated fancy veneer overlayed plywood floorings increased with increasing the acrylate functionality of the acrylated urethane oligomer. In the case of the UV cured film containing hexa-functional acrylated aliphatic urethane oligomer, high discoloration of the coated fancy veneer overlayed plywood flooring was observed near the cracks at the beginning of the chemical treatment. In this study, it was found that the degradation of the UV cured film caused by an alkaline reagent was higher than that of the UV cured film caused by an acidic treatment.

• 대한환경공학회지
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• 제28권4호
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• pp.429-437
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• 2006

화학세정폐수에 함유되어 있는 citric acid의 효율적인 처리방안을 수립하기 위해 $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton 산화방법을 이용하여 각각 citric acid의 제거효율 및 그에 따른 전력소비량을 평가하였다. 그 결과 조사된 최적 처리조건에서 $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton 산화방법을 이용한 citric acid 농도에 근거한 TOC 제거효율은 각각 95.5%, 92.3%, 91.5%로 조사되었으며, 그에 따른 전력소비량은 $11.26kWh/m^3,\;3.85kWh/m^3,\;0.799kWh/m^3$으로 조사되었다. 이 결과에 의하면 세가지 광화학적 산화방법 모두 유기물질이 90% 이상 제거되어 citric acid의 분해에 효과적인 것으로 판단되었다. 그러나 Photo-Fenton 산화방법이 다른 방법에 비해 처리에 소요되는 반응시간이 짧은 것으로 나타났다. 또한 광화학적 산화방법의 운영비를 결정짓는데 중요한 요소인 전력소모량 측면에서도 Photo-Fenton 산화방법이 다른 방법에 비해 우수한 것으로 조사되어 본 연구에서 비교하는 세가지 방법 중 citric acid 처리에는 Photo-Fenton 방법이 효율적인면과 경제성면에서 가장 적합한 처리기술로 결론지을 수 있었다.

• 한국전기전자재료학회논문지
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• 제18권12호
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• pp.1143-1147
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• 2005

In this study, we report an improved efficiency of Organic light emitting diodes(OLEDs), using $UV/O_3$ treated anode and different cathode. We investigated the efficiency of OLEDs by $UV/O_3$ treatment of ITO surface. We Performed $UV/O_3$ treatment and found that $UV/O_3$ treatment enhanced the performance of OLEDs. The fundamental structure of the OLEDs was ITO $anode/{\alpha}-NPD/Alq_3/Al$ or Li:Al cathode. The Li:Al can improve the OLEDs efficiency dramatically in cathode because it has lower work function than Al. Current-voltage, Luminance-voltage characteristics and luminance efficiency were measured at room temperature.

• 한국전기전자재료학회논문지
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• 제22권3호
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• pp.230-234
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• 2009

Hydrogen and Oxygen plasma treatments have been done on sonochemical grow ZnO nanorods by varying treatment temperature and time, The changes(position and intensity) in ultraviolet(UV) peaks and green peaks of photoluminescence(PL) spectroscopy have been measured, Experimental results showed; i) in the case of hydrogen plasma treatment, the blue shift of UV peak and the increase of PL intensity of the UV peak were observed as the increase of the process time and temperature, ii) in the case of oxygen plasma treatment, the red shift of green peak was observed and the ratio of $I_{Green}/I_{UV}$ was also increased, as the increase of the process time and the temperature.

• 보존과학회지
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• 제28권3호
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• pp.229-233
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• 2012

본 연구에서는 상아 시편에 습식 세척과 약산을 통한 색상 회복 처리를 실시하고, 이에 대한 안정성 평가를 실시하였다. 사용된 상아 시편은 블랙라이트와 능형무늬 분석을 통해 진위여부를 확인하였다. 습식 세척제로는 상아 및 골각류 유물 처리에 주로 사용되는 증류수, 에틸알코올, 아세톤으로 처리하였으며, 세척 결과 표면관찰, 중량 측정, 색도 측정에서 특별한 변화가 관찰되지 않았다. 약산을 통한 색상 회복 실험에서는 UV-A, UV-B, UV-C 세 가지 파장 하에서 1주일간 인공 열화 시킨 시편을 대상으로 약산 용액인 2%와 5%로 희석된 아세트산 용액과 레몬즙을 이용해서 처리하였다. 처리 결과, 모든 시편에서 표면에 균열과 공극이 관찰되었으며, 레몬즙을 사용한 경우 시편의 색이 붉게 변색되어 유물에 적용이 불가능하다고 판단된다.