• 한국세라믹학회지
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• 제26권6호
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• pp.795-801
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• 1989

The polycrystalline mullite fiber was synthesized from various combination of starting materials including metal alkoxides and colloidal sol by the sol-gel process. The best spinnability was observed in the sol which showed shear thinning and hysteresis (i.e., thixotropic flow), indicating that the network structure was broken down as the shear rate increased. The mullite fiber was polycrystalline after firing and characterized by thermal analysis, XRD, FT-IR spectroscopy, rheological measurements, and SEM.

• 태양에너지
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• 제12권2호
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• pp.18-27
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• 1992

졸-겔 기술에 의해 $WO_3$ 다충박막이 유리와 ITO coated glass 위에 증착되었다. 특성은 XRD, 분광광도계, DTA/TGA, SEM/EDAX 그리고 RBS에 의해서 분석되었다. 균질한 $WO_3$막은 유리기판위에 dipping속도 5mm/s에서 증착 되었으며 이 시료는 희석된 HCI 전해액을 사용하여 착색시킨 결과 낮은 근적외선 투과율을 나타내었다. DTA 결과 $380^{\circ}C{\sim}500^{\circ}C$ 범위의 gel data는 $WO_3$의 결정화 온도 형성을 결정하였으며 이 측정치는 졸-겔 박막의 결정화 온도와 일치하였다. RBS에 의해 착색되지 않은 $WO_3$ 졸-겔 막의 화학조성은 $WO_3$였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 춘계학술발표강연 및 논문개요집
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• pp.116-116
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• 2001

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 추계총회,초청강연,특별강연,연구발표회
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• pp.103.1-103
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• 2000

• 한국재료학회지
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• 제14권10호
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• pp.749-753
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• 2004

In this study, we attempt to synthesize the $Sr_{3}SiO_{5}:Eu$ yellow phosphor by sol-gel technique. Based on the blue emitting diodes as primary light source, white light emitting diodes have been manufactured using the $Sr_{3}SiO_{5}:Eu$ yellow phosphor as the luminescent material. Luminescent efficiency of yellow phosphor as well as that of blue LED is very important factor to enhance the luminescent efficiency of white LED. In order to improve the luminescent efficiency, we have synthesized the $Sr_{3}SiO_{5}:Eu$ phosphor by sol-gel technique. To research optimum condition of gelation reaction, the ratio of $H_{2}O$ to TEOS was fixed as 60:1. When the drying temperature was at $100^{\circ}C$, emission intensity was better than at $70^{\circ}C$. The critical $Eu^{2+}$ concentration was estimated to be about 0.05 mol and sintering temperature at $1300^{\circ}C$ was indicated best emission intensity.

• 한국세라믹학회지
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• 제24권5호
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• pp.423-430
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• 1987

Characteristics of Al2O3-ZrO2 powders prepared by sol-gel process and their sintering behavior were investigated as a function of calcination temperature. The sol-gel processed powders were calcined at 800, 900, 1000, 1100, 1200$^{\circ}C$, and analyzed by X-ray diffraction technique. Pore size and distribution of green compact of the calcined powders were measured by mercury porosimeter. It is suggested that the optimal temperature of calcination for the sintering of Al2O3-ZrO2 powder prepared by sol-gel process is 1100$^{\circ}C$. In the Al2O3-17vol.% ZrO2 sintered specimen, which was sintered at 1600$^{\circ}C$ for 2hrs in air, 69vol.% tetragonal phse existed.

• 한국재료학회지
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• 제16권10호
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• pp.599-605
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• 2006

N-(3-triethoxysilylpropyl)-1,4-diaminoanthrquinone-2,3-dicarboximide (TESP-DADI), an organic blue pigment, has been prepared and incorporated into silica solid matrix reacting triethyl orthosilicate (TEOS) via sol-gel method. Morphology and microstructure of resulting hybrid pigment were studied employing SEM and TEM. The micrographs and particle size distributions showed that uniform pigment can be obtained employing TEOS-based sol-gel method forming silica core. Particle size distribution of dispersed pigment in water was examined using the technique of dynamic light scattering. The ensuing pigment dispersion ink was subjected to various physicochemical evaluation such as viscosity, surface tension, inkjet stability, storage stability, and color change as inkjet ink using spectrophotometric, and microscopic techniques.

• 한국세라믹학회지
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• 제34권7호
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• pp.774-780
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• 1997

Porous low reflective coating films of SiO2.ZrO2 system were prepared from the mixed alkoxide solutions of Zr(O-nC3H7)4 and partially prehydrolyzed TEOS by the sol-gel method using the dip-coating technique. In the case of 90SiO2.10ZrO2 porous coating films with HCl and H2O content was 0.3 mole and 4 mole, 378 m2/g of the specific surface area, 0.254 cm3/g of total pore volume, 30-50$\AA$ of average pore diameter. The transmittance of 90SiO2.10ZrO2 porous coated films was 95.38% at the wavelength of 550 nm, compared with the parent glass, the transmittance was increased with 4.38%.

• The Korean Journal of Ceramics
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• 제6권2호
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• pp.159-163
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• 2000

Alumina fibre has been synthesized successfully by sol-gel technique. Boehmite sol was prepared by hydrolyzing aluminium iso-propoxide and peptizing it with nitric acid. The stable sol thus obtained was used for fibre drawing when their viscosity reached the required value as a result of progress of the hydrolyzation and polycondensation reaction. The fibres dried at 11$0^{\circ}C$ for 12 hours were sintered at 1$600^{\circ}C$ for 5 hours. A reasonable sintered density with better microstructure and strength have been attained using 2 wt% of urea, magnesia and silica as sinter additives. Thermal analysis with sintering additives of 2 wt% and phase determination of the heat treated fibres using XRD and FT IR spectra confirms the phase transitions. The observation of surface and cross-section of the fibres were made using SEM. Fibres of uniform circular cross-section is obtained by fixing the shape in a setting solution.

• 센서학회지
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• 제7권4호
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• pp.243-253
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• 1998

전해질 센서 감지막으로 사용되어 온 PVC 감지막은 센서 표면과의 낮은 부착력으로 인하여 센서 수명을 단축시켰고, 감지막의 규격화와 양산화가 어려웠다. 이러한 문제를 해결하고자 감지막 용액은 중성 캐리어(ionophore), 고분자 지지체(TEOS:DEDMS=1:3), 용매(에탄올) 그리고 촉매(염산)들을 혼합하여 sol-gel 방법으로 제조하였다. 그리고 감광성 고분자물질(THB30)로 만들어진 마이크로풀(micropool)내에 리프트-오프(lift-off) 기법으로 감지막을 형성하였다. 제작된 전해질 센서는 MISFET(metal-insulator-semiconductor field-effect transistor)의 전형적인 전기적 특성을 보였다. K-, Ca-, Na-ISFET은 넓은 농도범위에서 각각 53, 25, 50 mV/decade의 감도를 보였다. 감응시간은 약 90초이며 드리프트는 약 0.05 mV/hour였다. Sol-gel 법과 리프트-오프 기법은 감지감 형성에 적용될 수 있었으며, 센서의 규격화와 양산화를 개선시킬 수 있을 것으로 기대된다.