• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.528-531
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• 2000

ZnS:Cu phosphor used on powder electroluminescent device has a green emission in low frequency and a blue emission in high frequency. In this paper, to obtain the powder electroluminescent device of the blue emission in low frequency, the emission properties with mixed the ratio between phosphor and dye was investigated. The mixed ratio of the dye was from 0 to 5 weight percent. To inquire into the blue emission, the emission spectrum, the CIE coordinate system and the brightness were measured.

• Journal of Radiation Protection and Research
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• 제41권3호
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• pp.185-190
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• 2016

Background: In order to measure neutron energy spectra, the conventional Bonner Sphere Spectrometers (BSS) are widely used. In this spectrometer, several measurements with different size Bonner spheres are required. Operators should, therefore, place these spheres in several times to a measurement point where radiation dose might be relatively high. In order to reduce this effort, novel neutron energy spectrometer using an onion-like single Bonner sphere was proposed in our group. This Bonner sphere has multiple sensitive spherical shell layers in the single sphere. In this spectrometer, a band-shaped thermal neutron detection medium, which consists of a LiF-ZnS mixed powder scintillator sheet and a wavelength-shifting (WLS) fiber readout, was looped to each sphere at equal angular intervals. Amount of LiF neutron converter is reduced near polar region, where the band-shaped detectors are concentrated, in order to uniform the directional sensitivity. The LiF-ZnS mixed powder has an advantage of extremely high light yield. However, since it is opaque, scintillation photons cannot be collect uniformly. This type of detector shows no characteristic shape in the pulse height spectrum. Subsequently, it is difficult to set the pulse height discrimination level. This issue causes sensitivity fluctuation due to gain instability of photodetectors and/or electric modules. Materials and Methods: In order to solve this problem, we propose to replace the LiF-ZnS mixed powder into a flexible and Transparent RUbber SheeT type $LiCaAlF_6$ (TRUST LiCAF) scintillator. TRUST LiCAF scintillator can show a peak shape corresponding to neutron absorption events in the pulse height spectrum. Results and Discussion: We fabricated the prototype detector with five sensitive layers using TRUST LiCAF scintillator and conducted basic experiments to evaluate the directional uniformity of the sensitivity. Conclusion: The fabricated detector shows excellent directional uniformity of the neutron sensitivity.

• Archives of Pharmacal Research
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• 제4권2호
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• pp.75-84
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• 1981

As the cetyltrimenthy ammonium bromide (CTAB) concentration increases to $2{\times}10^{-4}$/M the absorption maximum of ethyl orange (EO) makes a blue shift from 475 mm to 395 mm. At higher concentration of CTAB than $2{\times}10^{-4}$ / M the absorption maximum shifts to higher wavelength than 395 nm. A new peak at 395 nm is shown to result from the mixed micelle due to dye stacking interaction rather than from a change in dye geometry. Because Raman spectra of EO on interaction with varying amount of CTAB are similar to that of EO in water. EO retains trans azo type on interaction with CTAB. There is a change of c.m.c.s. of CTAB for the mixed micelle in the presence of salt. The effect of added salt on C. M. C. of CTAB for the mixed micelle is given that the logarithm of the c. m. c. is a linear function of the logarithm of the sum of the c. m. c. and the concentration of added salt.

• 전기학회논문지
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• 제59권12호
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• pp.2245-2249
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• 2010

The physical properties of the LB films with merocyanine dyes have been published and attract attention due to the possibility of molecular structure control. The evaluation of the thin films was focused for the purpose of molecular structure control. The molecular structure in the case of the thin films with dyes can be examine by optical absorption spectra measurements. In the result measured by optical absorption spectra, the $[DX]_{1-x}[DO]_x$ LB films shows a large in-plane anisotropy and the transition dipole moment of red-shifted band is preferentially oriented perpendicular to the dipping direction of the film, while that of the blue-shifted band prefers the dipping direction. The spectrum for $0_{\circ}$, $90_{\circ}$-polarized light coincides with the spectrum for non-polarized light and also with the spectrum was observed in the LB film deposited using a fresh solution. These results show that the aging process does not cause a structural change in chromophore but a change in the degree of molecular orientation. In the results, study of the merocyanine dyes LB films using optical absorption spectra would an interesting problem of absorbance peak shifts and mixed components.

• 한국분무공학회지
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• 제9권3호
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• pp.29-34
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• 2004

To investigate characteristics and micro-explosion of single-droplets of emulsified fuel, water is mixed with diesel oil by using ultrasonic energy fuel feeding system. The fuel characteristics is analysed through H-NMR spectrum and micro-explosion phenomena of the emulsified fuel is also investigated. The life times of droplets of conventional diesel fuel, ultrasonic energy added diesel fuel and emulsified fuel we obtained additionally. According to this study, the micro-explosion phenomena of single-droplets happen in atmospheric pressure condition, a curve form of emulsified fuel's life tim is different from diesel fuel's one and the change of chemical structures is a cause of ultrasonic-energy-added diesel fuel effect.

• 한국멀티미디어학회논문지
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• 제18권12호
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• pp.1468-1474
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• 2015

Efficient spectrum sharing is an important issue in Device-to-Device (D2D) communications underlaying cellular networks as it can mitigate the interference to cellular users and improve the performance of the systems. In this paper, we formulate the radio resource allocation in D2D communications as a mixed nonlinear integer programing. We show the formulated problem is NP-hard and thus a polynomial time algorithm to solve is not possible. Since such a problem is very hard to obtain the optimal solution within a short running time, we instead propose a fast heuristic suboptimal algorithm to mitigate the interference caused to cellular users and improve the performance of the systems. Simulation results are provided to evaluate the performance of the proposed algorithm.

• 대한수의학회지
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• 제26권2호
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• pp.225-228
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• 1986

Progesterone immunogen has been synthesized and its melting point, Rf-value, UV and IR spectrum have been measured to develope the essential step in antisera production against low molecular weight substance. Mixed anhydride reaction was used to conjugate $11{\alpha}$-hydroxy-progesterone with succinic anhydride. Melting point of one intermediate compound was $156^{\circ}C$, and Rf-value was 0.41 in benzene : acetone : methanol (5 : 5 : 2). Maximum absorbance was measured at 242nm and ${\varepsilon}$ was $1.641{\times}10^4cm^2/mole$. Loss of hydroxy group was observed at 3450nm, and carbonyl group was appeared at 1160nm, 1250nm and 2960nm. These results indicated that the intermediate compound was progesterone hemisuccinate. Maximum absorbance of progesterone bovine-serum albumin(BSA) conjugate was observed at 250nm. Molar ratio of progesterone to BSA was average 15.4 on UV spectrum.

• Journal of Astronomy and Space Sciences
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• 제14권1호
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• pp.117-125
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• 1997

파브리-페로 간섭계는 높은 해상도(∼1,000,000)를 갖고 있어 최근에 우주과학의 여러 분야에 응용되고 있다. 이 간섭계의 작동 원리를 이해하기 위해서는 수학적 모델링이 필요하고, 간섭계로부터 얻어진 간섭무늬를 해석하기 위해서는 정확한 장비 특성함수를 아는 것이 필수적이다. 간섭계로부터 나온 스펙트럼은 발광원으로부터의 순수 신호와 장비의 특성함수가 콘볼루션과정을 통하여 섞여있고, 순수 신호는 발광원의 양자 상태, 온도와 공기 덩어리의 움직임 등의 정보가 들어 있다. 따라서 이 순수 신호를 모델링하여 이론적인 장비 특성 함수와 콘볼루션하면 실제 얻어질 스펙트럼을 예측할 수 있다.

• Bulletin of the Korean Chemical Society
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• 제34권2호
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• pp.553-557
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• 2013

The stretching vibration of OH of ice Ih is studied by Car-Parrinello molecular dynamics in regarding the effect of mixed H/D contamination while the vibrational spectrum is considered by velocity-velocity autocorrelations of the sampled ensemble. When hydrogen atoms are immersed randomly into the deuterated ice, a typical vibrational frequency of OH stretching mode is observed to be similar to that from the pure $H_2O$ ice. When focusing on the correlation of isolated neighboring OH stretching, a narrower and blue shifted peak is observed at the high frequency range as a result of the screening from the complex many body correlations by $D_2O$ environment. It is also specifically related to the symmetric intermolecular correlations between neighboring OH stretching modes. More enhanced high frequency range can be explained by the expansion of such two body correlations to collective many body correlations among all possible OH stretching modes. This contribution becomes important when it involves in chemical interactions via excitation of such vibrational states.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1659-1660
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• 2006

After end of the 20th environmental problem was became issue. So about mercury free lighting sources are being studied very much. In this paper, a mercury and electrode free bulb was designed. in this bulb was injected mixed of Xe, Ne and Kr Gases. and then the bulb was discharged by 13.56MHz RF Power after spectrum, color coordinates and brightness were measured by spectrum meter CS-1000. Measured results were compared and analyzed, also analysis was able to do a characteristic of a gas defensive fight in proportion to a mixing ratio. Therefore the most of high brightness which was 4500cd/m2 was gained in 1:1 ratio of Xe:Ne at 60W input power.