• Macromolecular Research
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• v.16 no.5
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• pp.424-428
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• 2008

We prepared an ionic gel polymer electrolyte for dye-sensitized solar cells (DSSCs) without leakage problem. Triiodide compound (BTDI) was synthesized by the reaction of benzene tricarbonyl trichloride with diethylene glycol monotosylate and subsequent substitution of tosylate by iodide using NaI. Bisimidazole was prepared by the reaction of imidazole with the triethylene glycol ditosylate under strongly basic condition provided by NaH. BTDI and bisimidazole dissolved in an ionic liquid were injected into the cells and permeated into the $TiO_2$ nanopores. In situ crosslinking was then carried out by heating to form a network structure of poly(imidazolium iodide), thereby converting the ionic liquid electrolytes to a gel or a quasi-solid state. A monomer (BTDI and bisimidazole) concentration in the electrolytes of as low as 30 wt% was sufficient to form a stable gel type electrolyte. The DSSCs based on the gel polymer electrolytes showed a power conversion efficiency of as high as 1.15% with a short circuit current density of $5.69\;mAcm^{-2}$, an open circuit voltage of 0.525 V, and a fill factor of 0.43.

• Journal of the Korean Ceramic Society
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• v.35 no.3
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• pp.264-272
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• 1998

The effect of catalytic condition on the properties of SiO2 aerogels has been investigated and then the dri-ed aerogels were partially densified to induce mechanical strength by heat treatment in order to prepare Type-VI silica by Sol-Gel method. Aerogel made by 1-step base process had the highest skeletal density lowest shrinkage and the smallest particle size. But in case of using acid catalyst in both 1st and 2nd step had the lowest skeletal density highest shrinkage and the largest particle size The aerogel synthesized by 1-step base process was most transparent because of its homogeneous microstructure. During heat treatments cracks occurred below 200$^{\circ}C$ for aerogel with the skeletal density lower than 1.9 g/cm3 but the with the higher skeletal density did not cracked up to 800$^{\circ}C$ shrinkage and skeletal density increased as heating temperature increased due to condensation and viscous sintering mechanism.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.191-191
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• 2003

가시광선영역에서 높은 광학적 투명도를 갖는 n-type 반도체인 ZnO 박막은 넓은 범위에서 응용되고 있다. 현재 ZnO 박막의 특성 향상을 위하여 여러 원소(Al, Ga)의 도핑을 시도하고 있다. 특히 Al-doped ZnO 박막은 sol-gel dip coating에 의해서도 높은 전기전도도와 투과율로 활발히 연구되고 있다 본 논문에서는 여러 도핑농도를 갖는 Al-doped ZnO 박막이 sol-gel dip coating법에 의해 준비되었다. Al-doped ZnO 박막은 zinc acetate [Zn($CH_3$COO$_2$)ㆍ2$H_2O$] powder 와 여러 도핑농도를 갖는 aluminum nitrate (Al(NO$_3$)$_3$ㆍ9$H_2O$) powder를 알코올에 용해하여 $H_2O$, Ethylene glycol, Ethylene diamine 등을 첨가하여 제조하였다 XRD와 SEM (Scanning electron microscope)이 막의 상형성 분석을 위해 이용되었으며, 가시광선 영역 투과율(UV/VIS spectrophotometer)과 표면전기저항(four point probe)이 주요 특성으로 분석되었다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.4
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• pp.332-342
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• 1995

The important factors of reaction conditions in sol-gel transition of silicon alkoxide solution have been reviewed and discussed on the basis of Raman study. Various factors such as type of catalyst, alkoxide, solvent, drying control chemical additive and water content affect the conversion mechanism in sol-gel process.

• Journal of Veterinary Clinics
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• v.11 no.1
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• pp.389-392
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• 1994

To purify transforming growth factor type beta(TGF-$\beta$) in canine platelets, Sephadex G-75 gel filtration and semipreparative HPLC were carried out. The column of $2.0 {\times}120cm$ was used for gel filtration and one inch semipreparative column filled with SP-Toyopeal for HPLC. Electrophoresis and bioassay using African green monkey kidney cell were used for identification of TGF-$\beta$ Crude TGF-$\beta$ of 2.75mg was extracted from 5.2g of the platelets by the treatment of acid/ethanol. In gel filtration of crude TGF-$\beta$, 4 peaks were observed at the detection of spectrophotometer at 280nm. Electrophoresis and bioassay identified the 3rd peak TGF-$\beta$. Linear gradient elution from 0 to 3M NaCl in sornipreparative HPLC showed TGF-$\beta$ at 1.5M NaCl. Gel filtration was less expensive and useful method for the purification of TGF-$\beta$.

• Journal of the Korean Ceramic Society
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• v.33 no.10
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• pp.1079-1088
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• 1996

Discontinuous ${\gamma}$-LiAlO2 fibers for fiber-reinforcing MCFC matrixes have been produced by the sol-gel process using the centrifugal spinning apparatus of the Rotary type. Gel fibers could be obtained through spinning of stable LiAlO2 complex polymetric sols under the optimum spinning conditions (hollow-disc rotating velocity 9000 rpm sol feeding rate of 4ml/min flowing N2 temperature of 4$0^{\circ}C$ and flowing N2 pressure of 4 bar). It was found that defect free and densified ${\gamma}$-LiAlO2 fibers with the relative density of 98% and the mean diameter of 4.7${\mu}{\textrm}{m}$ were prepared when the spinned fibers were heat-treated to 100$0^{\circ}C$ on the specified heating schedule. in particular the mean diameter and length of fibers could be controlled by the pressure of flowing N2 and the chopping-sieving method respectively.

• Journal of Pharmaceutical Investigation
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• v.25 no.4
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• pp.339-345
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• 1995

For the effective treatment of aphthous stomatitis, the matrix type mucoadhesive patches containing triamcinolone acetonide have been formulated. The drug layer was obtained by drying the polymer gel which was prepared with carbomer 934P, ammoniomethacrylate copolymer, titanium dioxide and polyethylene glycol 400. The effects of the content of additives on physical characteristics of the polymer gel and the drug layer were evaluated. The addition of carbomer increased the yield point and the zero-shear viscosity of polymer gel as well as the thickness, the water absorption ratio, the adhesive time and $T_{50%}$ of drug layer. The adhesive time and the water absorption ratio of drug layer were also improved by the addition of ammoniomethacrylate copolymer, but the addition of titanium dioxide had decreased the zero-shear viscosity of polymer gel and the adhesive time of drug layer.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.396-399
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• 2009

Thin-film transistors (TFTs) with an aluminum indium oxide (AIO) channel layer were fabricated via a simple and low-cost sol-gel process. Effects of annealing temperature and time were investigated for better TFT performance. The sol-gel AIO TFTs were annealed as low as $350^{\circ}C$. They exhibit n-type semiconductor behavior, a mobility higher than 19 $cm^2/V{\cdot}s$ and an onto-off current ratio greater than $10^8$.

• KSBB Journal
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• v.17 no.1
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• pp.106-109
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• 2002

Gel electrophoresis of DNA is a well known technique in molecular biology. This technique is simple, rapid to perform, and capable of adequately separating fragments of DNA. A number of mixtures of DNA fragments ("DNA size markers") are frequently employed in a purpose of extrapolating the sizes or the amount of DNA molecules during gel electrophoresis. DNA size markers are constructed by digesting plasmid DNA, bacteriophage DNA, or recombinant DNA molecules with one or more restriction enzymes. However, liquid suspension containing DNA size marker needs to be kept at a low temperature during storage and shipping. In an attempt to maintain the DNA samples at room temperature for extended period of time, lyophilization of DNA with addition of nuclease inhibitor was studied. Gel loading buffer was also added to the lyophilized DNA to provide additional convenience such that DNA size marker was the "ready-to-use" followed by simply reconstituting with distilled water.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.9
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• pp.527-531
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• 2016

In this study, p-type thin film transistors consisting of CuO channels were fabricated by sol-gel process, with copper (II) acetate monohydrate precursors. At $500^{\circ}C$, the deposited films were fully converted into monoclinic phase CuO. The fabricated CuO thin film transistors deliver field effect mobility in saturation regime of $0.015cm^2/Vs$, and $I_{on}/I_{off}$ of ${\sim}10^3$. The degradation of the performance of the fabricated CuO thin film transistor caused by the exposure to air has been studied.