• Macromolecular Research
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• v.16 no.8
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• pp.670-675
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• 2008

A series of pH and temperature-responsive (N,N-diethylacrylamide-co-methylacrylic acid) copolymers were synthesized by radical copolymerization and characterized by elemental analysis, Fourier-transform infrared (FT-IR), nuclear magnetic resonance (NMR) $^1H$, $^{13}C$ and LLS. The effects of salt and pH on the phase transition behaviors of the copolymers were investigated by uv. With increasing NaCl concentration, significant salt effects on their phase transition behaviors were observed. UV spectroscopic studies showed that the phase transition became faster with increasing NaCl concentration. In addition, the phase transition behaviors of copolymers were sensitive to pH. The pH and temperature sensitivity of these copolymers would make an interesting drug delivery system.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.43.4-44
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• 2016

We observed the high resolution spectra of a solar-neighborhood planetary hosting star HD 20794. The analysis of spectroscopic data was performed using URAN and SYNTHE programs. These spectra allow us to determine the effective temperatures, surface gravities, microturbulent velocities and, chemical abundances. Bond et al. (2008) found chemical abundance for 11 elements, but using the Spectrum synthesis method we have so far determine about 30 elements. We have derived iron metallicity $[FeI/H]=-0.42{\pm}0.03$, $[FeII/H]=-0.43{\pm}0.012$, and surface gravity, log g = 4.48, in good agreement with values from previous investigation.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.233-234
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• 2015

We present results of a new high-resolution spectroscopic study of the RS CVn-type binary system EI Eridani (HD26337). We used high S/N ratio LSD profiles to measure a new RV orbit of the primary component and new orbital parameters. We found evidence of strong spectral line profile variations at time intervals indicating the existence of short-lived (few days) spots on the surface of the primary component. We measured a projected rotation velocity of star of 53.2 km/s.

• Journal of the Semiconductor & Display Technology
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• v.17 no.1
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• pp.1-5
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• 2018

Wood Polymer Composites(WPC) have attracted significant attention because of ecological and environmental concerns. However, the structure of Wood Flour containing many hydroxyl groups(-OH) reduces the interface adhesion to Phenol-formaldehyde(PF) and it decreases the mechanical properties of the PF/Wood Flour Composites. The present work involves the modification of Wood Flour using silanes reinforced with Phenol-formaldehyde to enhance the mechanical properties of the composites. The spectroscopic properties of the composites were analyzed using FT-IR, XPS(X-ray Photoelectron Spectroscopy) and the mechanical properties i.e., tensile strength, flexural strength and impact strength were studied. We confirmed the modification effect of silanes by spectroscopic analysis, and the mechanical properties of the composites using wood flour modified by silanes were significantly improved.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.1-10
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• 2022

This paper reviews the principles, advantages, and disadvantages of main explosives detection technologies, as well as research areas needed in the future. Explosives detection technology can be classified into spectroscopic methods, sensor techniques, and olfactory type sensors. There have been advances in explosives detection technology, however studies on discriminatory, portability, and sensitivity for explosives detection still remained competitive.

• Journal of Life Science
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• v.5 no.4
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• pp.181-189
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• 1995

Carotenoids liberated from the red carotenoprotein from the skin of ascidian(Halocynthia roretzi)were developed on TLC, and two bands were obtained with different Rfvalues. Their chemical reactivities and spectroscopic properties were studied and elucidated as astaxanthin diester and astaxanthin monoester. After saponification of carotenoid ester, GC analysis was performed. The carotenoid ester contained oleic acid, palmitic acid and palmitoleic acids as 50% of total amount, and had higher content unsaturated fatty acid including eicosapentanoic acid than saturated fatty acid.

• Proceedings of the Korean Fiber Society Conference
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• 1989.06a
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• pp.61-61
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• 1989

• Korean Journal of Pharmacognosy
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• v.47 no.4
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• pp.307-311
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• 2016

Three tetrastilbene compounds were isolated from the aerial parts of Carex dimorpholepis Steudel (Cyperaceae) through repeated column chromatography. Their chemical structures were elucidated as kobophenol A (1), cis-miyabenol A (2), and kobophenol B (3), respectively, by spectroscopic analysis. These compounds were isolated for the first time from this plant.

• Proceedings of the Optical Society of Korea Conference
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• 1991.07a
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• pp.9-14
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• 1991

질소 기체의 코헤런트 반 스톡스 신호를 상자형 위상전합 방식으로 측정하였으며, 이 신호로부터 온도 및 밀도를 구하기 질소 기체의 코헤런트 라만 신호를 섭동이론을 이용하여 계산하였다.

• Proceedings of the Optical Society of Korea Conference
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• 1991.07a
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• pp.15-22
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• 1991

The general aspects of Laser Resonance Ionization Spectroscopy (RIS) and its application are investigated. Combination of laser selective photoionization and mass spectrometer as apromising spectroscopic as well as an analytical tool is mainly considered. The application of RIS includes mercury (Hg) atomic spectroscopy, trace analysis of lead (Pb) and resonance enhanced two photon ionization spectroscopy of Cis-hexatriene.