• Electric Engineers Magazine
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• v.233 no.2
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• pp.11-16
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• 2002

많은 사람들이 썬탠을 즐기며 건강해 보일것이라고 생각한다. 하지만 태양 광선을 많이 쬐면 건강에 해롭다는 것에 관심이 모아지고 있다. 태양 광선은 자외선 영역 안에서 어느정도 약간 포함되어 있는 파장을 가진 빛을 많이 포함하며 자외선을 과도하게 흡수하면 화상을 가져올 수 있기 때문에 주의를 요해야 한다.

• Applied Chemistry for Engineering
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• v.33 no.3
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• pp.279-283
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• 2022

UV-vis spectroscopy is one of the powerful tools for measuring the concentrations of reactant and products during a chemical reaction. However, there is an limitation of using the technique when the reaction undergoes in high concentration and high temperature. Color analysis using camera images can provide the identical results with UV-vis analysis with regardless of the sample concentration and temperature. The catalytic reduction reaction of resazurin to resorufin was investigated using the color analysis with the color spaces such as CIE L^*a^*b^*. Moreover, the color analysis enabled the independent analysis of two different material's concentrations without the deconvolution of overlapped wavelengths unlike the case of using UV-vis spectroscopy.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.649-655
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• 2010

This study investigated the degradation of phenol using sonication and/or UV-C. The effects of frequency, temperature, pH in solution, argon purging, with UV intensity were estimated in sonication-only, UV-only, and the combined reaction of sonication with UV. The optimum condition for degrading phenol in the sonication-only reaction was 35 kHz, $5^{\circ}C$, and pH 4. As this condition approximately 30% degradation of phenol was achieved within 360 min. However, phenol in the UV-only at $19.3\;mw/cm^2$ under the same condition was completely degraded within 60 min. In the combined system of sonication with UV, the degradation of phenol was well fitted to first-order rate model, and phenol was completely degraded within 360 min and 45 min at UV intensity of $7.6\;mW/cm^2$($17.3{\times}10^{-3}\;min^{-1}$) and $19.3\;mW/cm^2$($138.1{\times}10^{-3}\;min^{-1}$), respectively. Adding methanol, as a radical scavenger, in the phenol degradation in the sonication reaction indicates that OH radical is a major factor in the degradation of phenol. The order of degradation efficiencies of phenol was in the order of as follows; combined reaction of sonication with UV > UV-only > sonication-only.

• Korean Journal of Environmental Biology
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• v.20 no.3
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• pp.205-215
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• 2002

Effects of artificial and solar W-B radiation on five rhodophytes (Curdiea racovitzae, Gigaytina skottsbergii, Mazzaella obovata, Myriogramme manginii, Palmaria decipiens) from Antarctica have been investigated using PAM fluorescence in laboratory and in the field. Laboratory studies showed that there were significant differences in the UV sensitivity between different species, and that the differences appeared to be correlated with the depth of collection of the specimens. It was apparent from the observations that the samples such as M. manginii and P. decipiens collected from 20-30 m depths were move sensitive to W-B radiation compared with those collected from shallower depths, The present study confirmed that an acclimation to the surrounding light regime could be an important factor to determine the UV-sensitivity of a species or individuals and that PAM measurements are rapid and non-destructive methods to evaluate UV influences. From field studies on M. manginii and P. decipiens it was observed that both plants exhibited changes in the effective quantum yield, with the minimum values nt noon followed by n recovery in the evening. Photoinhibition occurred in these species could therefore be accounted for by so- called dynamic photoinhibition. It seems likely that this protective mechanism may contribute to survival of the species in shallow water where they may encounter intense solar radiation. The presence or absence of the W- B component under solar radiation differently affected the photosynthetic recovery process, and the rate of recovery was much stoney in UV- present than in W- absent conditions. Functional role of W- B appears to delay the recovery of photosynthesis in the studied macroalgae. Differential sensitivity to UV-B recognised between M. manginii and P. decipiens seemed to correspond well with the amount of UV-absorbing substances (UVAS) contained in the respective species. Higher tolerance to solar radiation by the latter species may be due to the higher amount of UVAS. There were variations of UVAS concentrations in algal thalli depending on the season and depth of collection.

• Journal of the Korean Chemical Society
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• v.55 no.1
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• pp.98-103
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• 2011

This study was done for the preparation of macromolecular material with UV-blocking features by adding the benzophenone group that is commonly used as a UV-absorbent and $TiO_2$ which is known to be a very stable material in chemical and physical aspects. Also, we compared the level of UV absorbency of the polymer produced from polymerization with previous materials and measured basic properties such as water content, refractive index and optical transmittance of produced contact lenses. The results of the measurement showed that the refractive index and water content of the contact lens with added UV-absorbent was 1.430~1.440 and 35.0~45.0% respectively, which was similar to that of previous contact lenses. Also, for optical transmittances of each wave length, contact lenses without the UV-absorbent was 89%, 88% and 89% respectively for UV-A, UV-B and visible light, indicating that the UV transmittance is very high though contrary with cases of contact lenses with added 2-hydroxy-4-methoxy-benzophenone and 2,4-dihydroxy-benzophenone which showed transmittances of 0% and 6% respectively for UV-A and UV-B showing a UV-blocking effect. Meanwhile, contact lenses with added $TiO_2$ showed transmittance of 6% and 51% respectively for UV-A and UV-B also showing a UV-blocking effect. The visible transmittance was 77~89% showing that it satisfies the visible transmittance required for ophthalmological materials.

• 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.

• Applied Chemistry for Engineering
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• v.29 no.3
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• pp.298-302
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• 2018

Photocatalytic properties of nitrogen doped titanium dioxide were investigated. Photocatalytic degradation of methylene blue under UV and visible light was carried out to characterize N-doped $TiO_2$. The result of XPS indicated that nitrogen atoms substitute for oxygen sites within the crystal structure of $TiO_2$. In the UV-Vis DRS spectra, N-doped amorphous $TiO_2$ absorbed UV light with little absorption of visible light, while the absorption of visible light of amorphous/anatase $TiO_2$ remarkably increased. Methylene blue photocatalytic degradation appeared by the irradiation of UV or visible light onto the N-doped anatase phase of $TiO_2$. However, the degradation rate of visible light was lower than that of UV light. The photocatalytic degradation rate of the amorphous/anatase $TiO_2$ sample was higher than that of the anatase $TiO_2$. These results indicate that the high surface area of amorphous/anatase $TiO_2$ sample, which was about three times larger than those of the anatase $TiO_2$ sample, may be related to small particles of N-doped anatase $TiO_2$.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.2
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• pp.37-45
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• 2007

We have measured the spectral transmittances of UV blocking soft contact lenses, regular soft contact lenses and regular RGP lenses using the method suggested in ANSI Z80.20 standard. In order to evaluate visible light transmitting and UV blocking characteristics, we have calculated transmittances by integrating over the specific spectral ranges, i.e., visible light, UVA, UVB and UVC. We found that mean transmittances of visible light for all three categories were over 90.0 % which could be considered as within acceptable range for a contact lens. The transmittance of the UVA and UVB radiation for the UV blocking soft lenses except some cases was within UVR (Ultraviolet radiation) transmittance standard. The UV blocking ability of regular soft and RGP lenses was poor as rather expected. These results will be expected to assist clinical opticians and practitioners in utilizing the transmittance characteristics about the contact lens.

• The Science & Technology
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• v.11 no.10 s.113
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• pp.57-58
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• 1978

태양광선이 강하게 내려 쬐이는 열대지방에 살고 있는 사람의 피부색이 검은 까닭은? ……이것이 인류가 오랜동안 진화하면서 자연환경에 적응한 것일까? 이에 대한 해결은 종래 여러 설이 있었다. 이에 대해 광에 약한 비타민류가 태양광선속의 자외선에 의해 광분해되는것을 막아주기 위함이란 견지에서 엽산염을 써서 시험관으로 실험하고 또 광선치료를 받은 백인이나. 열대주민의 비타민부족에 의한 산과영역의 이상들의 관찰로 이 설을 실증하는 연구가 미ㆍ미네소타대학 의학부의 브란트ㆍ잇튼 두 의학자에 의해 발표되었다.

• 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.