• Composites Research
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• v.27 no.6
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• pp.236-241
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• 2014

This paper aims to evaluate material property variation of polymer concretes under ultra-violet exposure condition. The components and mixing ratio of the polymer composite specimens were determined by the previous research results. The equivalent UV exposure time was calculated with the consideration of the power of metal halide lamp and maximum 3 years were selected for the experiments. From the tests, it was found that the generated heat during UV exposure affected much the material properties of polymer concrete by means of post cure. As a result, the compressive strength increased and ductility factor decreased.

• Proceedings of the KAIS Fall Conference
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• 2006.11a
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• pp.313-316
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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 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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.527-536
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• 2019

This study examines the degradation of PTT BCF and fading behavior of disperse dye by heat treatment and UV irradiation. The behavior in strength degradation of PTT BCF after treat treatment was examined by measuring the tensile strength of samples. The strength retention of PTT BCF rapidly decreased with increasing exposure time at 150℃. The K/S value decreased with increasing temperature and its trend accelerated with increasing exposure time on heat. The behavior on strength degradation of PTT BCF and the fading of disperse dye on it were studied under UV irradiation at various temperatures. The tensile strength of PTT BCF and the K/S value of the sample dyed with disperse dye after UV irradiation decreased with increasing temperature and exposure time. PTT BCF exposed under UV irradiation exhibited lower strength and K/S value compared with the sample after heat treatment. Additional study on the effects of additives used to improve the resistance to fading of disperse dye and degradation of PTT BCF revealed that antioxidant and UV absorbent in PTT BCF showed a small improvement in the strength degradation of PTT BCF and the fading of dye.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.11a
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• pp.175-178
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• 2005

본 연구는 물벼룩을 환경 중 UV-B와 유사한 강도에 노출시켜 8세대 이상 적응시킨 후 Daphnia magna의 UV-B 적응이 광독성 오염물질의 독성 민감도에 미치는 영향을 관찰하였다. UV-B에 적응된 D. magna는 UV-B와 Cu 동시 노출 시 자외선에 적응되지 않은 D. magna에 비해 높은 저항성을 보였다(p<0.1). 그 이유는 D. magna가 UV-B에 적응되는 과정에서 oxidative stress에 대한 방어/회복 능력이 증가하여 동일한 ROS를 생성하는 Cu에 노출되었을때 효과적으로 저항할 수 있었기 때문으로 해석된다. Pyrene, fluoranthene, anthracene, As, Cd, Ni은 독성이 증가하거나 동일하게 나타났다.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.3
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• pp.263-273
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• 2012

Recent studies have uncovered attractive properties of para-coumaric acid (PCA) as a potential skin hywhitening agent. The purpose of the current study was to examine its UVB-shielding effects. Effects of PCA on the viability of HaCaT cells exposed to UVB were assessed in vitro in comparison with other aromatic amino acid metabolites that have similar UV absorption spectra. For in vivo test, PCA cream (1.5 %) and cream base were topically applied to the dorsal skin of SKH-1 hairless mice and the inflammatory responses due to UVB exposure were monitored by changes in skin color (erythema) and thickness (edema). The cream application-UVB exposure regimen was repeated every other day for a total of 12 sessions. When HaCaT cells were irradiated with UVB, there was a dose-dependent decline in cell viability. The cell viability decline due to UVB exposure (10 mJ $cm^{-2}$) was significantly prevented by 100 ${\mu}M$ PCA, cinnamic acid, urocanic acid, or indole acrylic acid by 39, 27, 39, or 31 %, respectively. Topical application of PCA cream onto the dorsal skin of hairless mice (10 ${\mu}g\;cm^{-2}$) attenuated the changes of color parameters, $L^*$, $a^*$, $b^*$ values, and thickness of the UVB (150 mJ $cm^{-2}$)-exposed skin by 59, 50, 58, and 53 %, respectively. The current study, together with the previous studies that demonstrated the antimelanogenic effects of PCA, suggested that PCA may prevent not only dyspigmentation but also inflammatory reactions in the UVB-exposed skin.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.2
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• pp.139-150
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• 2019

This study is investigated sunscreen formulation that enhances UV absorption efficiency by UV light. Ethylhexyl methoxycinnamate (OMC) is one of the most common UV filters. Many studies have been conducted about photostability of OMC. It is well known that under the UV exposure, trans-OMC could turn to cis-OMC, or produce various photoproducts including its dimers. Those chemical structure changes were understood as the reason of a decrease in UV absorption efficiency upon UV exposure. However, it was found that OMC and isoamyl p-methoxycinnamate (IMC) could even enhance its UV absorption efficiency when it was exposed to UV light in an environment similar to actual use. In order to develop sunscreen formulation that enhances UV absorption efficiency by UV light, emollient with high polarity and compatibility should be avoided from the formular. Those emollient seemed to prevent OMC or IMC from producing photoproducts under UV light. Finally, a sunscreen formulation (UV sensing SPF boosting formular) enhancing UV absorption efficiency by UV was developed by the UV activated SPF boosting technology, and the effect of the sunscreen was evaluated. in vitro SPF of the sunscreen was increased from 50.69 to 72.33 when it was exposed to UV light and its in vivo SPF (53.7) was 56.10% higher than that of the control sunscreen (below 34.4).

• 건강소식
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• v.32 no.5
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• pp.20-21
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• 2008

따스한 봄볕은 여성들의 마음을 설레게 한다. 이 무렵은 덥지도, 춥지도 않은 날씨로 인해 외출이 잦아지는 때이기도 하다. 당신은 이제껏 거의 완벽한 화장법을 구사하면서도 피부 나이를 속일 수 없어 괴로워해 왔다. 왜일까? 바로 피부에 가차 없이 가해지는 자외선 때문일 것이다. 만개한 꽃은 여인의 판단력을 흐리기에 충분하다. 그만큼 햇볕에 피부가 노출되는 상황은 경우에 따라 위험할 수도 있다. 과연 자외선으로부터의 안전지대는 어디인가? 당신의 피부 노화방지 프로젝트, 지금부터 시작이다.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.2
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• pp.229-234
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• 2002

The human eye and skin is exposed daily to solar energy. Expecially, the ultraviolet radiation (UVR) exposure has been damaged as an important causative factor in corneal disease. These damage of cornea was effected the retina. Therefore the eye function was effected very significant damage. As a results the protect of UVR in the eye is very important in ocular health. Therefore in living the intensive ultraviolet radiation environment by solar energy, human eye have protected the cornea and eyeball by the UV-blocking sunglass, eyeglass, goggles, and contact lens. Finally the specific UV-blocker lens devices available to the primary care for the subjects by optician. Of course, in the future these specific lenses have to development and study by fellowship.

• Proceedings of the Korean Environmental Health Society Conference
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• 2001.04a
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• pp.103-105
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• 2001