• Journal of radiological science and technology
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• v.39 no.4
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• pp.637-642
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• 2016

In this study, we prepared and characterized a acrylate based UV-curable plastic scintillator. It was used co-polymers TMPTA, DHPA and Ultima $Gold^{TM}$ LLT organic scintillator. The emission spectrum of the plastic scintillator was located in the range of 380~520 nm, peaking at 423 nm. And the scintillator is more than 50% transparent in the range of 400~800 nm. The emission spectrum is well match to the quantum efficiency of photo-multiplier tube and the fast decay time of the scintillation is 12 ns, approximately. This scintillation material provides the possibility of combining 3D printing technology, and then the applications of the plastic scintillator may be expected in human dosimetry etc.

• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.670-674
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• 2009

3-Chromonealdehyde(2,2-disubstituted)hydrazone derivatives were synthesized by dehydration condensation. They are green-emitting materials for organic light emitting device (OLED) composed of electron acceptor of 3-chromonealdehydes and electron donor of 2,2-disubstituted hydrazones by a conjugated structure. The structural properties of reaction products were analyzed FT-IR and $^1H-NMR$ spectroscopy. The thermal stabilities and reactivities were measured by melting points and yields. The UV-visibles and PL properties can be determined by excitation spectra and emission spectra, respectively.

• Applied Chemistry for Engineering
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• v.22 no.6
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• pp.594-598
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• 2011

We study on the preparation of green emitting materials for organic light emitting device. 3-chromonealdehyde derivatives possessing a conjugated structure, which were composed of electron acceptor of 3-chromonealdehydes and electron donor of diamines, were synthesized by dehydration-condensation process. The structural properties of reaction products were analyzed FT-IR and $^1H-NMR$ spectroscopy. The thermal stabilities and reactivities were measured by melting points and yields. The UV-visibles and PL properties can be determined by excitation spectra and emission spectra, respectively.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.4
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• pp.304-309
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• 2015

To evaluate the degree of contamination caused by oil spill accident in the sea, the in-situ sensors which are based on the scientific method are needed in the real site. The sensors which are based on the fluorescence detection theory can provide the useful data, such as the concentration of oil. However these kinds of sensors commonly are composed of the ultraviolet (UV) light source such as UV mercury lamp, the multiple excitation/emission filters and the optical sensor which is mainly photomultiplier tube (PMT) type. Therefore, the size of the total sensing platform is large not suitable to be handled in the oil spill field and also the total price of it is extremely expensive. To overcome these drawbacks, we designed the fluorimeter for the oil spill detection which has compact size and cost effectiveness. Before the detail design process, we conducted the experiments to measure the excitation and emission spectrum of oils using five different kinds of crude oils and three different kinds of processed oils. And the fluorescence spectrometer were used to analyze the excitation and emission spectrum of oil samples. We have compared the spectrum results and drawn the each common spectrum regions of excitation and emission. In the experiments, we can see that the average gap between maximum excitation and emission peak wavelengths is near 50 nm for the every case. In the experiment which were fixed by the excitation wavelength of 365 nm and 405 nm, we can find out that the intensity of emission was weaker than that of 280 nm and 325 nm. So, if the light sources having the wavelength of 365 nm or 405 nm are used in the design process of fluorimeter, the optical sensor needs to have the sensitivity which can cover the weak light intensity. Through the results which were derived by the experiment, we can define the important factors which can be useful to select the effective wavelengths of light source, photo detector and filters.

• Journal of the Korean Chemical Society
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• v.24 no.4
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• pp.310-314
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• 1980

Some minor carotenoid pigments, luteints, lutein monoester, torulene, $\gamma$-carotene, and 5,6-monoepoxy-$\alpha$-carotene-like have been separated and identified from the abdominal skin of Bombina Orientalis. Their structures have been established through the physical and chemical properties, VIS-UV and IR spectral characteristics, and chromatographic behaviors.

• YAKHAK HOEJI
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• v.35 no.1
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• pp.1-6
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• 1991

Fast Hartley transform(FHT) was used for the identification of derivative UV spectra of pharmaceuticals, with the advantages of relatively shorter computing time of FHT and more precise results. The arccosine value of dot product of two vectors of normalized FHT coefficients calculated from two compared derivative spectra was a reasonable parameter for the spectral identification. Using this parameter, the similar patterns of derivative spectra of 13 penicillins can be differenciated from each other. The concentration difference and the minor contamination did not interfere the results of identification procedures. All these procedures of identification were accomplished successfully by the computer program, [SPECMAN PLUS] version 1.30, which was developed for this article.

• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.45-50
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• 1969

On the basis of UV spectral changes and TBA reaction, malonaldehyde (MA) in aqueous solution receives considerable photochemical modification by UV light of short wavelengths around $260m{\mu}$. When aflatoxin is added in the solution, UV light of long wavelengths around $360m{\mu}$ induces such changes quite rapidly and although the rate of change is rather slow, it is also true even with ordinary laboratory illumination(fluorescent). The modification is irreversible in nature and the role of aflatoxin in this reaction is identified as a photosensitizer. The mechanism involved in this modification is apparently due to the parallel dimerization of MA molecules, but not by head to tail combination of the molecules.

• Journal of the Korean Chemical Society
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• v.34 no.6
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• pp.616-621
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• 1990

The spectrophotometric methods for the determination of Nd, Pr, Sm, Eu, Ho, Er were developed, using the multicomponent method of absorption spectra cointerference. The absorption spectra of individual Nd, Pr, Sm, Eu, Ho, Er, mixture of Sm, Eu, Ho, Er in hydrochloric acid solutions were investigated, and also a band register which includes the molar absorptions for all trivalent Nd, Pr, Sm, Eu, Ho and Er absorption band maxima were measured. The spectrophotometric determination of Nd, Pr, Sm, Eu, Ho and Er were investigated using the analytically significant absorption bands at 444.2, 575.1, 401.7, 394.2, 416.6, and 379.7 nm, respectively.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1977.10a
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• pp.200.1-200
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• 1977

핵산관련질의 구조식 및 핵산계 조미료로 사용되고 있는 $5'-IMPㆍNa_2$ 및 $5'-GMPㆍNa_2에$ 대한 업학적성질과 UV, IR 스펙트럼을 살펴보며 이들의 pH값을 제시한댜. 즉 5'-XMP 및 5'GMP등과 같은 nucleotide류는 모두 phosphomonoester group을 가지고 있는 제 1인산이 약 1, 제 2인산이 6정도인 2개씩의 pk값을 가지고 있으며 이외에도 pyrimidine핵에 OH기와 $NH_2가$ 있어서 용액의 pH에 따라 여러가지 형태의 이온형을 가질 수 있다.(중략)

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.308.1-308.1
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• 2013

여름철 건축물의 냉방 부하 저감 및 자동차 실내의 온도 상승을 억제하기 위하여 일반적으로 단열필름이 사용되고 있다. 실제 시중에 유통되고 있는 단열필름은 크게 유기물 기반의 제품과 무기물 기반 제품으로 나뉘고 있다. 본 연구에서는 유기물 기판의 단열 필름은 내구성이 거의 없기 때문에 무기물 기반의 제품을 위주로 연구를 진행하였다. 단열 필름의 단열 효과가 어느 정도인지를 정확히 알기 위하여 UV-Vis 스펙트럼 분석을 실시하였다. 항온 항습 장치를 이용하여 고온고습 조건에서 무기물 기반의 단열 필름의 성능 변화를 통하여 내구성 실험을 실시하였다.