• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.345-345
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• 2006

It is well known that poly(glutamate)s with long n-alkyl side chains form thermotropic liquid crystalline state by melting of the side-chain crystallites and also poly(glutamate)s such as poly(${\gamma}-benzyl\;L-glutamate$ )(PBLG), poly(${\gamma}-n-alkyl\;L-glutamate$), etc. in solvent form the isotropic, biphasic and liquid crystalline phases which contains cholesteric and columnar liquid crystalline forms depending on the polypeptide concentration. Although there is no diffusion study for PBLG in liquid crystalline state, because it is difficult to observed $^{1}H$ spectrum of PBLG in liquid crystalline state for its very short $^{1}H\;T_{2}$. In this study, the diffusional behavior of rodlike PBLG in concentrated solution is successfully elucidated as studied by the field-gradient $^{1}H$ NMR methods.

• Journal of the Korean Chemical Society
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• v.49 no.3
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• pp.334-338
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• 2005

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.433-435
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• 2005

We have studied the realigning behavior of liquid crystal molecules in liquid crystalline polymer/liquid crystal(LCP/LC) system when they are exposed to external stimulation such as bending and pressing. The birefringence of the LCP/LC in a flexible display device was measured as a function of bending or pressing deformation. The microscopic dynamic behavior of main chain, side chain, and the LC were characterized by FTIR and polarization optical microscopy. When the device is deformed in scattering memory state, liquid crystal(LC) director is found to align from randomly oriented domain state(scattering state) to homeotropic state.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.279-294
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• 2004

This study described about a liquid crystalline technology that is used in cosmetics industry. Various intermediate phases may exist between solid and liquid. At high surfactant concentration, several liquid crystalline phases can be made to have formed. Although molecular arrangement with crystallization is not regular, it is known that more relative regular state is liquid crystalline or meso-phase than liquid phase. Usually, it described in detail about manufacturing method that explained about a kind of liquid crystalline technology in cosmetics, a new liquid crystalline technology, and makes liquid crystalline. Specialty, it introduced about kind of special an emulsifier to form liquid crystalline. There were hydrogenated lecithin, ceramide, dipalmitoylhydroxyproline, DEA-cetyl phosphate, Gemini-surfactant in representative raw material to form liquid crystalline. Liquid crystalline extent that used polarization microscope to observe formation, and appears best from 400times, 600times, 1,000times well appeared. Also, droplet particle size that liquid crystal is made best 1.0-10.0$\mu\textrm{m}$ be. General emulsion more than superior result that measures the skin moisturizing effect to take advantage of liquid crystalline technology of vitamin was seen. As presence at a clinical result, wave and general emulsion more than superior result (more than 20%) that measures skin moisturizing effect about liquid crystalline of vitamin B$\_$5/ were seen (ANOMA t-test, p<0.05)

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1179-1184
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• 1998

Mesogenic and azo monomers were synthesized and copolymerized to obtain two copolymers composed of methacrylate and itaconate backbone. Glass transition temperatures of the copolymers were found to be slightly higher than ambient temperature. Both the copolymers showed liquid crystalline properties. Trans-cis isomerization in film state was observed under UV-irradiation with a light of 365 nm. Regarding the photochemical phase transition behavior, the transition rate of nematic-to-isotropic state was slightly faster in the methacrylate copolymer during irradiation at 365 nm and the rate of the reverse transition was much faster in itaconate copolymer under thermal effect.

• Bulletin of the Korean Chemical Society
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• v.28 no.2
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• pp.299-302
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• 2007

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1289-1290
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• 2001

• Applied Microscopy
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• v.42 no.3
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• pp.174-178
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• 2012

In the present study, the oxidation behavior of $Cu_{50}Zr_{50}$ and $Cu_{46}Zr_{46}Al_8$ metallic glasses has been investigated using transmission electron microscopy with a particular attention on the oxidation behavior in the supercooled liquid state. Identification of the oxidation product after continuous heating treatment shows that in $Cu_{50}Zr_{50}$ metallic glass, $ZrO_2$ with the monoclinic structure forms on the supercooled liquid as well as on the crystallized matrix. On the contrary, in $Cu_{46}Zr_{46}Al_8$ metallic glass, $ZrO_2$ with the tetragonal structure forms on the supercooled liquid, but that with the monoclinic structure forms on the crystallized matrix. The result indicates that the $Cu_{50}Zr_{50}$ metallic glass exhibits far better oxidation resistance in the supercooled liquid state than the $Cu_{46}Zr_{46}Al_8$ metallic glass.

• Applied Chemistry for Engineering
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• v.28 no.6
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• pp.679-684
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• 2017

Hydrated liquid crystalline vesicles incorporating a edge activator, which confers flexibility to the vesicle membranes, were prepared and niacinamide was encapsulated in them. The formation of liquid crystalline phases and their thermal phase transitions were investigated by polarized optical microscopy and differential scanning calorimetry (DSC), respectively. Droplet sizes of the vesicles were reduced to several tens of nanometers by incorporating edge activators, such as sodium deoxycholate, lysolecithin, or polysorbate 80. The amount of niacinamide permeated into a pig skin increased greatly using the hydrated liquid crystalline vesicles compared to the case where niacinamide was applied in an aqueous solution state. The vesicles incorporating 10% sodium deoxycholate increased the amount of niacinamide permeated nearly four times. These results suggest that edge activators are effective in improving the skin permeability of vesicles.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.933-935
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• 2002

In this paper, new non-chiral molecules with semi-fluorinated alkyl chains were synthesized varying the structure of central bent core unit. Their mesomorphic properties were investigated by DSC and polarized microscopy. The compound with 1,3-dihydroxy phenylene unit could form an enantiomeric smectic phase, but the remaining compounds with bent-core mesogenic unit were not liquid crystalline. In this presentation, their x-ray measurement and electro-optical property will be also described.