• 보존과학연구
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• s.33
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• pp.85-97
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• 2012

In this study, reliability assessment was carried out on UV(ultraviolet) indicators for the application of the indicator method on cultural heritages. As a result, some UV indicators(L, K, and M) proved to be unsuitable due to their low reactivity to UV and high reactivity to RH(relative humidity). On the other hand, indicator S showed considerable color changes and fading due to UV-B and UV-C according to the integral amount of UV irradiation. Indicator S showed the most distinct reaction to UV and a remarkable applicability to exhibition light, which are used in museums. Therefore, UV indicator S is an easy and useful monitoring tool for light environment management in cultural- property conservation facilities.

• Journal of Sericultural and Entomological Science
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• v.20 no.1
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• pp.11-14
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• 1978

This experiment was attempted to investigate the effect of removal of suboesophageal ganglion of Bombyx mori on the changes of free amino acids and fluorescent substances by means of paper chromatography. 1. There are no differences of quantity and component of free amino acids of formed eggs in moths between treatment and control. 2. Riboflavine content of formed eggs in treated moths is less than that of formed eggs in untreated moths. 3. Fluorescent substance which appeared on Rf value 0.06 was not detected in formed eggs of treated moths but found in those of control. 4. Fluorescent substance which appeared on Rf value 0 was noted in formed eggs of treated moths but not in those of control.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.8
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• pp.872-877
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• 2006

It has been concerned about the indoor air contaminants because of the hours spend in indoor space. These contaminants are emitted from various indoor facilities. Therefore, even though there concentrations are very low, adverse effects can't be ignored. However, treatment technologies are insufficient to deal with these contaminants. For this reason, the objective of this study was to investigate the feasibility of artificial ultraviolet(UV) detoxification using $TiO_2$ system for degrading formaldehyde contaminated indoor air. The experiment was also performed to investigate the formaldehyde removal effect of fluorescence lamp as an alternative UV light source because it is used in indoor as a light source. The results presented demonstrated that as the $TiO_2$ dosage is more and the reaction area is wider, the photocatalytic degradation rate does more enhanced. Degradation of TCE was more rapid used in $UV_{254}$ lamp than in fluorescence lamp. However, if it is operated during enough time, it will be able to remove the considerable quantity of TCE in case of using fluorescence lamp.

• Applied Chemistry for Engineering
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• v.31 no.2
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• pp.220-225
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• 2020

Hair is made of proteins containing various amino acids. Ultraviolet (UV) radiation is believed to be responsible for the most damaging effects of sunlight, and also plays an important role in hair aging. The purpose of this study was to investigate the changes in morphological and chemical structures after ultraviolet B (UVB) irradiation of human hair. The UVB-irradiated hair showed characteristic morphological and structural changes, compared to those of the normal hair. The result from a scanning electron microscope (SEM) equipped with an energy dispersive X-ray diffractometer (EDX) showed that the scale of UV-irradiated hair appeared to be rough and the amount of oxygen element was higher than that of the normal hair. Fluorescence and three dimensional (3D) topographical images were obtained by a confocal laser scanning microscope (CLSM). In 3D images, the green emission intensity of normal hair was much higher than that of fluorescing UVB-irradiated hair. The intensity of green emission reflects the intrinsic fluorescence of hair protein. Also, a fluorescent imaging method using fluorescamine reagent was used to identify the free amino groups resulting from a peptide bond breakage in UVB-irradiated hair. Strong blue fluorescence of UVB-irradiated hair, which indicates a very high level of amino groups, was observed by CLSM. Therefore, the fluorescamine as an extrinsic fluorescence could provide a useful tool to identify the peptide bond breakage in UVB-irradiated hair. Infrared image mapping was also employed to assess the cross-sections of normal and UVB-irradiated specimens to examine the oxidation of disulfide bonds. The degree of peak areas with strong absorbance for the disulfide mono-oxide was spread from the outside to the inside of hair. The spectroscopic techniques used alone, or in combination, launch new possibilities in the field of hair cosmetics.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.762-766
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• 1990

The effect of storage conditions on the oxidative stability of cholesterol in butter was studied by identifing cholesterol oxides by TLC. Experimental variables for storage conditions were packaging(packaged and unpackaged), storage temperature(ambient and refrigerated), light source(dark, fluorescent and ultraviolet), and storage period(2, 4, 6, and 8 weeks). No cholesterol oxides were detected from packaged butter under all storage conditions. When unpackaged butter was stored under darkness at ambient and refrigerated temperatures, cholesterol oxides were not detected even after 6 weeks of storage, but small amounts of $7{\alpha}-and\;7{\beta}-hydroxycholesterols$ were detected after 8 weeks of storage. When unpackaged butter was stored under ultraviolet light at ambient temperature, $7{\alpha}-hydroxycholesterol,\;7{\beta}-hydroxycholesterol$ cholestane-triol, and cholesterol epoxide were detected after 2 weeks of storage, and when fluorescent light was used instead of ultraviolet light, the same species of cholesterol oxides were detected after 6 weeks of storage.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.180-180
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• 2013

희토류 이온이 치환 고용된 실리케이트계 형광체는 자외선으로 여기될 때 높은 발광 효율을 나타내기 때문에 광전 소자, 레이저, 형광램프에 응용할 수 있는 발광 재료로 상당한 관심이 집중되고 있다. 본 연구에서는 고상반응법을 사용하여 초기 물질 (99.99% 순도), (99.99%), (99.9%), (99.9%)을 화학 정량으로 준비하여 활성제 이온 Eu3+와 Sm3+의 함량비를 0, 0.01, 0.05, 0.10, 0.20 mol로 변화시켜 BaSiO3:RE3+ (RE=Eu, Sm) 형광체를 제조하여 그것의 발광과 흡광 특성을 조사하였다. Eu3+ 이온이 도핑된 BaSiO3 형광체의 경우에, 발광 스펙트럼은 모든 시료에서 전이에 의한 발광 스펙트럼을 보였으며, 특히 j=2에서 가장 강한 적색 형광이 피크 620 nm에서 관측되었다. 상대적으로 발광 세기가 약한 595 nm 에 정점을 갖는 주황색 발광과 705 nm 에 피크를 갖는 적색 발광 스펙트럼이 관측되었다. Eu3+ 이온의 함량비가 0.15 mol 일 때 세 영역의 발광 스펙트럼의 세기는 최대값을 나타내었다. 주흡광 스펙트럼은 Eu3+ 이온의 함량비에 관계없이 397 nm에서 관측되었다. Sm3+ 이온이 도핑된 BaSiO3 형광체의 경우에, 모든 시료는 Sm3+ 이온의 함량비에 관계없이 전이에 의한 발광 스펙트럼을 보여주고 있으며, 특히 j=7/2에서 가장 강한 주황색 형광이 피크 603 nm에서 관측되었다. 상대적으로 발광 세기가 약한 567 nm에 정점을 갖는 황색 발광과 651 nm에 피크를 갖는 적색 발광 스펙트럼이 관측되었다. Sm3+ 이온의 함량비가 0.05 mol 일 때 세 종류의 발광 스펙트럼의 세기는 최대값을 나타내었다. Sm3+ 이온의 함량비가 더욱 증가함에 따라 모든 발광 스펙트럼의 세기는 순차적으로 감소하였는데, 이 현상은 농도 소광 현상에 기인함을 알 수 있었다. 주 흡광 스펙트럼은 Sm3+ 이온의 함량비에 관계없이 406 nm에서 관측되었으며, 이밖에도 상대적으로 세기가 약한 흡광 스펙트럼이 237 nm, 377 nm와 476 nm에서 관측되었다.

• Journal of the Korean Ceramic Society
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• v.38 no.9
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• pp.817-821
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• 2001

A new $Mg_{2-x}MN_xSnO_4$ phosphor with an inverse spinel structure was synthesized by the solid-state reaction technique. The photoluminescence properties of the $Mg_2SnO_4$:Mn phosphors were investigated under 147nm -vacuum ultraviolet ray excitation. The Mn-doped $Mg_2SnO_4$ phosphor exhibited high emission intensity with the spectrum centered at 500nm wavelength. It was explained that the green emission in $Mg_2SnO_4$:Mn phosphor has originated from energy transfer from $^4T_1$ to $^6A_1$ of $Mn^{2+}$ ion at tetrahedral site of the spinel structure. The $Mn^{2+}$ ion concentration exhibiting the maximum emission intensity under the excitation of 147nm-vacuum ultraviolet ray was 0.25mol%. And the decay time of the phosphor was shorter than 10ms.

• Nuclear Engineering and Technology
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• v.4 no.4
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• pp.331-339
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• 1972

For the syntheses of tritium labelled polystyrene, the basic material for the preparation of tritium luminous compound, various methods of labelling such as Tesla discharge, Wilzbach exposure, gamma irradiation, and U V. irradiation were compared in view of getting high specific activity-product. The obtained polystyrene-T(G) by the method of Tesla discharge and by the method of U. V. irradiation had specific activity of 1～1.2 mCi/mg, and these two methods were the most encouraging. Mixing of 1 part of polystyrene-T(G) with 4 parts of ZnS:Cu phosphor, in weight, appeared to be the most suitable ratio in tile preparation of luminous compound in luminosity point of view. When 30 mg. of obtained luminescent mixture was applied on steel plate by using 1 ml. of the selected binder (i.e., 1g of commercial varnish in 100m1. of benzene) the luminosity maximum was ca. 20 micro Lambert. The prepared luminous compound was confirmed to be practically applicable for mine marker or dark-room light source.

• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.82-89
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• 1989

The fluorescence of $Eu^{3+},\;Tb^{3+}$ substituted for $La^{3+}$ in Lanthanum Oxychloride (LaOCl) has been studied. The fluorescence intensity of the $Eu^{3+},\;Tb^{3+}$ in LaOCl excited by Ultra-violet light were investigated on its activator concentration and discussed as the energy transfer process. The energy transfer from $Tb^{3+}\;to\;Eu^{3+}$ take place in the $Eu^{3+}\;and\;Tb^{3+}$ codoped LaOCl crystal. This process was confirmed to the change of concentration and the measurement of fluorescence decay time.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.45-50
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• 2018

The functional nanomaterials of fluorescent dye-doped silica nanoparticles(NPs) are applied to bio applications such as bio-labeling of DNA micro-array, and bio-imaging. Organic dye-doped fluorescent silica NPs exhibit excellent bio-compatibility, non-toxic, and highly hydrophilic properties. In this study, organic fluorescent dyes were dissolved in ethanol, and deionized(DI) water. Organic fluorescent dyes were physically adsorbed to silica NPs and chemically doped to silica NPs. The fluorescence characteristics(FLC) was investigated by UV lamp irradiation of 365 nm wavelength. As results, the FLC of dye-doped silica NPs exhibits better than dye-adsorbed silica NPs and the FLC was improved with the increase of concentration of doped-dyes. The fluorescent organic dyes were well dissolved in ethanol than DI water. The photostability of dye-doped silica NPs was superior than pure fluorescent organic dye. The FLC of optimized dye-doped silica NPs would be applied to agent of non-invasive fluorescence bio-imaging in live cell and in vivo.