• Journal of Photoscience
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• 제9권2호
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• pp.442-444
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• 2002

Seedlings of spinach (Spinacia oleracea L. "King of Denmark" and "Minsterland") were grown with or without supplemental UV-B under field conditions for five or nine days when their fifth or sixth leaves were expanding. Except two leaves which were just expanded and expanding, all other leaves of each seedling were removed before tested. One of these two leaves was exposed to UV-B irradiation and the other leaf was covered with lumiror film (no transmission below 320 nm) to prevent it from UV-B exposure. l,l-diphenyl-2-picrylhydrazyl scavenging activities (antioxidative activity) in leaves without covers were increased according to UV-B doses they were exposed to. And removal of UV-B exposure with lumiror decreased foliage antioxidative activities. This increase or decrease of activities in leaves did not dependent on the UV-B doses their paired leaves were exposed to in both two cultivars. The results demonstrated that spinach foliage antioxidants induced by UV-B exposure were not transported into another leaf.

• 한국가구학회지
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• 제26권4호
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• pp.428-434
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• 2015

In this study, we received each wood plastic composites (WPC) from three manufacturers. These WPCs were evaluated regarding their physical and mechanical properties of both before and after accelerated weathering by ultraviolet (UV) irradiation. The total time of exposure of the WPCs to UV irradiation was 1800 h. The water absorption, volumetric swelling and shrinkage of WPCs did not affected by UV irradiation. Among the mechanical properties, there was no significant differences in bending strength and screw withdrawal resistance of UV treated WPCs compared with those of reference WPCs. However, surface hardness of WPCs showed decrease under UV irradiation. Stereoscopic microscopy observation revealed deterioration of the surface layer polymer in all weathered WPCs by UV. Exposure of the WPCs to UV irradiation caused decomposition and disappearance of the polymer layer. From this result, we can estimate that damage of polymer by UV led to a decrease in the surface hardness of the WPCs. The wood flours retained original shape after accelerated weathering by UV irradiation.

• 한국응용과학기술학회지
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• 제12권2호
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• pp.157-163
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• 1995

The ultraviolet blocking agents used to skincare are largely classified ultraviolet scattering agent and ultraviolet absorbent agents. There are UVC, UVB, and UBA in ultraviolet ray(UV) showing shorter wavelength than visible light. Both visible light and UVA give rise to 1st dark-skinned phenomena. On exposure of the skin to UV, phenomena of skin variation are termed sunburn or suntan. There are chronic and acute adverse reactions in skin response to UV. The latter is caused by UVB, which has mainly effects on the skin. But lately due to destruction of ozone layer, UVA has more serious irritation on the skin than UVB. In this paper spectrometric properties of UV absorbent agents such as PABA, octyl-PABA, Urocanic acid, and 2-hydroxy-4-methoxy benzophenone in vitro have been investigate. As results, it was found that the three fomer were more suitable than the last. UV scattering measurements on the sample used inorganic pigments showed that pigments containing titanium dioxide had a better scattering effects than the inorganic pigments such as $Fe_2O_3$, $Al_2O_3$, etc.

• Korea Journal of Cosmetic Science
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• 제2권1호
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• pp.1-10
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• 2020

Protection mechanisms for skin damage of ultraviolet (UV) absorbers in personal care products for protection against UV are well studied, but not for hair protection. The purpose of this study is to describe and compare the changes of physical property produced in human hair by doses of the UV-B exposure causing protein degradation. To observe the change of physical properties in hair, the experimental intensity of UV-B exposure has been established on the basis of statistical data from official meterological administration as daily one hour sunlight exposure for two weeks. Polysilicone-15, ethylhexyl methoxycinnamate (OMC), and octocrylene were employed for UV-B absorber, and those were treated to hair swatch by rubbing wash through shampoo and conditioner. Bending rigidity displayed kinetically successive reduction at high doses of UV exposure up to the 8,000 s, and exhibited different level at each sample of UV-B absorber. However, the values of Bossa Nova Technologies (BNT) for shinning factor were already saturable at the 2,000 s exposure except that treated with polysilicone-15. The differential scanning calorimetry (DSC) to measure a strength of inner protein produces a successive reduction of enthalpy as like a reduction of bending rigidity upon UV exposure. Surface roughness from lateral force microscope (LFM) acquired immediately after UV exposure show a saturable frictional voltage which has been also found in a saturable BNT data as the time of UV exposure increases. Through researching the DSC and the LFM, shinning of hair was much correlated to the protein damage at the surface, and bending rigidity could be regulated by the protein structural damage inside hair. Therefore, the optimization of efficient strategy for simultaneous prevention of hair protein on the surface and internal hair was required to maintain physical properties against UV.

• 대한가정학회지
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• 제46권10호
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• pp.1-9
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• 2008

The purpose of this study was to increase uv-cut ability of cotton, ramie, and rayon fabrics dyed with safflower red colorants. For this purpose, samples treated with uv-cut agent and tannic acid were compared with the untreated samples after ultraviolet(uv)-light exposure in terms of K/S value, color changes(${\Delta}E$), SEM, and tensile strength retention. K/S value rapidly decreased with increasing exposure time, but K/S value of the samples treated with both uv-cut agent and tannic acid decreased less than that of untreated samples. As increasing exposure time, $L^*$ and $b^*$ increased, $a^*$ decreased, and so ${\Delta}E$ increased, indicating less red character and more yellow character in color. This leads to change hue, value and chroma value. But color change of samples treated with both uv-cut agent and tannic acid was less than that of untreated samples. SEM pictures showed a severe degradation by uv exposure in all samples. Tensile strength slowly decreased for 21 days. And after this point, the decreased proceeded more rapidly. Tensile strength retention of the samples treated with uv-cut agent and tannic acid was higher than that of untreated samples.

• 농업생명과학연구
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• 제45권6호
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• pp.115-124
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• 2011

본 연구는 누에의 식엽성 곤충을 대체할 실험곤충으로서의 유용성과 자외선이 한국산 곤충병원성선충 (Heterorhabditis sp. 202 strain, Heterorhabditis sp. Gyeongsan strain, Steinernema sp. 223 strain, S. carpocapsae Pocheon strain, S. glaseri Dongrae strain, S. longicaudum Nonsan strain)의 병원성과 생존에 미치는 영향을 알아보기 위하여 수행하였다. 누에에 대한 곤충병원성선충의 병원성을 조사한 결과 누에의 령기나 곤충병원성선충의 계통이나 종에 따라 상이한 병원성을 나타내었는데 5령충에 대해서는 Steinernematidae선충의 병원성이 높았고, 1령충에 대해서는 Heterorhabditidae선충의 병원성이 높았다. UV-C는 곤충병원성선충에 유해하여 노출 60분후에는 모든 선충이 치사되었다. UV-C 조사는 곤충병원성선충의 병원성에도 영향을 미쳐 노출 10분 후에도 누에나방 3령충에 대하여 6.7% 이하의 보정사충율을 나타내었다. 야외 뽕나무밭(UV량: $2.3mW/cm^2$)에서 곤충병원성선충, S. carpocapsae Pocheon strain을 엽면 살포 4시간 후 채취한 뽕나무 잎을 급상한 누에는 치사되지 않았다. 뽕잎에서 $4.0mW/cm^2$의 UV 1시간 노출은 곤충병원성선충, S. carpocapsae Pocheon strain의 누에에 대한 병원성에 차이를 보이지 않았다.

• 대한기계학회논문집A
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• 제40권8호
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• pp.731-736
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• 2016

본 연구에서는 의용생체공학에 널리 사용되는 미소바늘과 같은 3차원 고종횡비 미소구조물을 용이하게 제작할 수 있는 하이브리드 자외선 노광법에 대해 기술한다. 하이브리드 자외선 노광법은 기존에 사용되고 있는 경사노광, 회전노광 및 역노광을 혼합한 방법으로, 경사 및 회전노광은 경사진 축대칭 형상을 가지는 3차원 미소구조물의 제작이 가능하도록 하고 역노광은 자외선 노광공정 중 필연적으로 발생하는 하부기판에서의 자외선 반사를 최소화 시킨다. 자체 개발한 자외선 노광시스템과 SU-8 음성감광제를 이용하여 하이브리드 자외선 노광법의 다양한 공정조건이 최종 제작된 3차원 고종횡비 미소구조물 형상(종횡비, 선단의 곡률반경 등)에 미치는 효과를 확인한다. 또한 SU-8의 소프트 베이킹(soft baking) 조건과 미소구조물 선단 형상 사이의 관계에 대해서도 논의한다.

• 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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.214-217
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• 1999

Polymeric composite insulators have been in use for outdoor insulation. However, our knowledge about their long-term performance in a outdoor environment is still very limited. Especially, these insulator are subjected to the environmental stress such as ultraviolet radiation. Hence, in this paper. the influence of UV radiation on the aging of the shed materials was evaluated. For the aging evaluation, these insulators studied by experiment methods such as contact angle measurement. oxidation induced time. SEM/EDX, FTRI-ATR, tracking test for the different insulator samples. With the increased UV exposure time, samples are shown to exhibit degradation comparable to those of new ones

• 한국전자통신학회논문지
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• 제17권3호
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• pp.499-506
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• 2022

2021년 동해북부선 착공으로 비무장지대(Demilitarized Zone:DMZ)의 평화적 활용의 기대치가 높아지고있다. 이에 따라 비무장지대를 안보생태관광으로 활용한 인근 해변에서의 레저관광 활동에 대비해야 한다. 그러나 오존층의 파괴로 인한 지표면 자외선(Ultravilolet:UV) 양의 증가에도 불구하고 아직까지 자외선 노출 위험가이드라인이 없다. 본 논문에서는 원격탐사를 이용한 비무장지대 인접 해안에서의 자외선 반사량 측정하고 분석하였다. 제시된 결과가 인근지역 레저관광 활동에서의 자외선 가이드라인 마련에 기초자료로 활용되기를 기대한다.