• 한국재료학회지
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• 제13권3호
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• pp.195-199
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• 2003

The $p-CdIn_2$$Te_4$single crystal was grown in the three-stage vertical electric furnace by using Bridgman method. The quality of the grown crystal has been investigated by the x-ray diffraction and the photoluminescence measurements. From the photoluminescence spectra of the as-grown $CdIn_2$$Te_4$crystal and the various heat-treated crystals, the ($D^{\circ}$, X) emission was found to be the dominant intensity in the photoluminescence spectrum of the $CdIn_2$T $e_4$:Cd, while the ($A^{\circ}$, X) emission completely disappeared in the $CdIn_2$T $e_4$:Cd. However, the ($A^{\circ}$, X) emission in the photoluminescence spectrum of the $CdIn_2$T $e_4$:Te was the dominant intensity like an as-grown $CdIn_2$T $e_4$crystal. These results indicated that the ($D^{\circ}$, X) is associated with $V_{Te}$ acted as donor and that the ($A^{\circ}$, X) emission is related to $V_{cd}$ acted as acceptor, respectively. The $p-CdIn_2$T $e_4$crystal was found to be obviously converted into the n-type after annealing in the Cd atmosphere. The origin of ( $D^{\circ}$, $A^{\circ}$) emission and its TO phonon replicas is related to the interaction between donors such as $V_{Te}$ or $Cd_{int}$, and accepters such as $V_{cd}$ or T $e_{int}$. Also, the In in the $CdIn_2$X$CdIn_4$was confirmed not to form the native defects because it existed in the stable form of bonds.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.98-99
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• 2008

To obtain the single crystal thin films, $AgGaSe_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$, respectively. The temperature dependence of the energy band gap of the $AgGaSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g$(T) 1.9501 eV - ($8.79\times10^{-4}$ eV/K)$T^2$/(T + 250 K). After the as-grown $AgGaSe_2$ single crystal thin films was annealed in Ag-, Se-, and Ga-atmospheres, the origin of point defects of $AgGaSe_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10K. The native defects of $V_{Ag}$, $V_{Se}$, $Ag_{int}$, and $Se_{int}$ obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Ag-atmosphere converted $AgGaSe_2$ single crystal thin films to an optical p-type. Also, we confirmed that Ga in $AgGaSe_2$/GaAs did not form the native defects because Ga in $AgGaSe_2$ single crystal thin films existed in the form of stable bonds.

• 대한화장품학회지
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• 제29권2호
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• pp.181-191
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• 2003

This study described about method that form liquid crystal gel (LCG) by main ingredient with hydrogenated lechin (HL) in OW emulsion system. Result of stability test is as following with most suitable LCG's composition. Composition of LCG is as following. To form liquid crystal, an emulsifier used $4.0\;wt\%$ of cetostearyl alcohol (CA) by $4.0\;wt\%$ of HL as a booster, Moisturizers contained $2\;wt\%$ of glycerin and $3.0\;wt\%$ of 1.3-butylene glycol (1,3-BG). Suitable emollients used $3.0\;wt\%$ of cyclomethicone, $3.0\;wt\%$ of isononyl isononanoate (ININ), $3.0\;wt\%$ of cerpric/carprylic triglycerides (CCTG), $3.0\;wt\%$ of macademia nut oil (MNO) in liquid crystal gel formation. On optimum conditions of LCG formation, the pHs were formed all well under acidity or alkalinity conditions. Considering safety of skin, PH was the most suitable $\pm61.0$ ranges. The stable hardness of LCG formation appeared best in $32\;dyne/cm^2.$ Particle of LCG is forming size of $1{\~}20\;{\mu}m$ um range, and confirmed that the most excellent LCG is formed in $1{\~}6\;{\mu}m$ range. According to result that observe shape of LCG with optical or polarization microscope, LCG could was formed, and confirmed that is forming multi-layer lamellar type structure around the LCG. Moisturizing effect measured clinical test about 20 volunteers. As a result, moisturizing effect of LCG compares to placebo cream was increased $30.6\%$. This could predicted that polyol group is appeared the actual state because is adsorbed much to round liquid crystal droplets to multi-lamellar layer's hydrophilic group. It could predicted that polyol group is vast quantity present phase that appear mixed because is adsorbed to round liquid crystal to multi-lamellar layer's hydrophilic group. This LCG formation theory may contribute greatly in cosmetics and pharmacy industry development.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2608-2612
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• 2009

The unequivocal solid-state structure and stereochemistry of the hetaryl leuco-TAM dye, 2,2’-(2-phenyl propane- 1,3-diylidene) bis(1,3,3- trimethylindoline) derivatives were established using X-ray single crystal analysis. The X-ray crystal analysis showed that the (Z, E)-isomers only formed stereoselectively, with a so-called “threebladed propeller” conformation, from the reaction of a Fischer base and benzaldehyde derivatives. These isomers were stacked in a juxtaposition to form a dimer or a double dimer, adopting either a triclinic, with P-1, or monoclinic crystal system with a space group P21/n in the unit cell of the crystal.

• 한국결정성장학회:학술대회논문집
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• 한국결정성장학회 1999년도 PROCEEDINGS OF KACG FALL MEETING, SEOUL, 4 DECEMBER, 1999
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• pp.93-99
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• 1999

It is definite trend that the functional devices are to be integrated by miniaturizing of individual components. Bulk crystals turn into wafer form, while thin film of the functional materials is being fabricated for single and multi-layer devices. In addition, single crystals with multi-function performance would be desirable for further miniaturization. crystal growers have the responsibility for synthesis single crystals work to meet ever increasing requirement of future devices.

• 한국결정성장학회지
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• 제14권2호
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• pp.63-67
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• 2004

층상 구조의 cobalt dedecanesulfate 화합물을 합성하였다. 여러 온도 영역에서 상 전이가 일어나면서 층간 거리의 큰 변화가 생겼다. 상온에서 단일 층 구조의 cobalt dodecanesulfate 화합물이 고온에서 탈수된 화합물의 이중층의 구조로 변화되었다.

• 한국세라믹학회지
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• 제17권1호
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• pp.35-41
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• 1980

Alumina extraction from raw Hadong kaolin with sulfuric acid was studied to obtain relatively pure alumina. Factors as acid concentration, heating temperature and conditions of ammonium alum crystal formation from extracted solution are also surveyed and most of iron oxide in kaolin is eliminated in crystallization of ammonium alum. Pure crystal obtained from the extracted solution with ammonium sulfate is relatively free from iron containment in mother liquor. Alumina in ammonium alum crystal is converted to gibbsite form after complete hydrolysis in ammonia gas.

• 대한화학회지
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• 제20권3호
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• pp.198-205
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• 1976

Parr의 Integral Hellmann-Feynman이론을 비대각꼴에 까지 일반화하여 의의를 갖도록 하였으며 그 특징을 논하였다. 그리하여 이 비대각꼴을 결정장론에 미치는 배치작용의 효과를 검토하는데 적용함으로서, 모든 차의 섭동 에너지를 하나의 묶음으로서 도입하였다. 그 결과 ${\Gamma}$, S 및 m로 특징지워지는 상태들에게, 파라미터화 할 수 있는 공통적인 동경적분이 존재하지 않음을 밝혔다. 그러나 만일 각 성분에 변형이 없고 동경성분에게 동등한 변형만이 있는 여기된 배치들의 작용만을 허락한다면, 이는 고전적인 결정장론에서 결정장 파라메터 10 Dq와 Condon-Slater 적분 $F^n$의 척도를 변경시키는 결과를 초래함을 알게 되었다.

• 한국결정성장학회지
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• 제12권4호
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• pp.196-201
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• 2002

The $AgInS_{2}$ epilayers with a chalcopyrite structure grown using a hot-wall epitaxy method have been confirmed to be a high quality crystal. From the optical absorption measurements, a temperature dependence of the energy band gap on $AgInS_{2}/GaAs$ was found to be $Eg(T)=2.1365eV-(9.89{\times}10^{-3}eV)T^{2}/(2930+T)$. After the as-grown $AgInS_{2}/GaAs$ was annealed in Ag-, S-, and In-atmospheres, the origin of point defects of $AgInS_{2}/GaAs$ has been investigated by using photoluminescence measurements at 10 K. The native defects of $V_{Ag},\;V_{S},\;Ag_{int}$ and $S_{int}$ obtained from photoluminescence measurements were classified as donors or accepters. It was concluded that the heat-treatment in the S-atmosphere converted $AgInS_{2}/GaAs$ to an optical p-type. Also, it was confirmed that In in $AgInS_{2}/GaAs$ did not form the native defects because In in $AgInS_{2}$ did exist in the stable form.

• 한국전기전자재료학회논문지
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• 제19권12호
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• pp.1160-1166
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• 2006

Maxwell-displacement-current (MDC) measuring technique has been applied for the investigation of monolayers of poly(vinyl alcohol)s bearing azobenzene side-chains (6Az5PVA) mixed with p-pentyl-p'-cyano-biphenyls (5CBs) on a water surface. For mixed monolayers containing trans-form 6Az5PVA and LCs, displacement current due to photo isomerization was not generated with alternative photo-irradiation with UV and svisible light. In contrast, for mixed monolaters containing cis-form 6Az5PVA and LCs, displacement current was generated. Finally, it was found that the alignment layers deposited in cis-form could photoregualte the orientation of LCs.