• 한국세라믹학회지
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• 제36권2호
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• pp.220-224
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• 1999

질화규소 겔케스팅 공정제어를 위하여, MeOH의 첨가가 겔화유도시간과 성형체의 건조속도 및 기계적 특성에 미치는 영향에 대하여 조사하였다. 그 결과, 10~20 vol%의 MeOH 첨가에서 겉보기 겔화유도시간은 가장 크게 나타났으며, 이때의 건조속도는 약 25~40%의 증진효과를 나타내었다. 분산매에 대하여 40% MeOH 첨가 범위에서 성형체의 기계적 가공은 가능하였으나, 겔캐스팅 성형체의 상대밀도 및 강도는 다소 낮아졌다.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2002년도 춘계학술대회 논문집
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• pp.237-238
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• 2002

Particle - bound water changes the physical and chemical properties of aerosol particles, such as size and light scattering properties. Consequently, it is necessary to remove water vapor from ambient aerosols before aerosol particles are sized and counted. Silicon gel diffusion dryer is commonly employed for this purpose. However, it can not be operated continuously While in operation, silicon gel becomes progressively more loaded with water and must periodically be regenerated by drying off the water. (omitted)

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제33회 KOSCO SYMPOSIUM 논문집
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• pp.235-241
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• 2006

Catalytic combustion is one of the suitable methods for micro power source due to high energy density and no flame quenching. Catalyst loading in the micro structured combustion chamber is one of the most important issues in the development of micro catalytic combustors. In this research, to coat catalyst on the chamber wall, two methods were investigated. First, $Al_2O_3$ was selected as a support of Pt and $Pt/Al_2O_3$ was synthesized through the alumina sol-gel procedure. To improve the coating thickness and adhesion between catalyst and substrate, heat resistant and water solvable organic-inorganic hybrid binder was used. Porous silicon was also investigated as a catalyst support for platinum. Through the parametric studies of current density and etching time, fabrication process of $1{\sim}2{\mu}m$ of diameter and about $25{\mu}m$ depth pores was confirmed. Coated substrates were test in the micro channel combustor which was fabricated by the wet etching and machining of SUS 304. Using $Pt/Al_2O_3$ coated substrate and Pt coated porous silicon substrate, conversion rate of fuel was over 95% for $H_2$/Air premixed gas.

• 한국연소학회지
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• 제11권2호
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• pp.7-14
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• 2006

Catalytic combustion is one of the suitable methods for micro power source due to high energy density and it can be applied to micro structured chamber without consideration of quenching since it is flameless combustion. Catalyst loading in the micro structured combustion chamber is one of the most important issues in the development of micro catalytic combustors. In this research, to coat catalyst on the chamber wall, two methods were investigated. First, $Al_2O_3$ was selected as a support of Pt and $Pt/Al_2O_3$ was synthesized through the alumina sol-gel procedure. To improve the coating thickness and adhesion between catalyst and substrate, heat resistant and water solvable organic-inorganic hybrid binder was used. Porous silicon was also investigated as a catalyst support for platinum. Through the parametric studies of current density and etching time, fabrication process of $1{\sim}2{\mu}m$ of diameter and about $25{\mu}m$ depth pores was confirmed. Coated substrates were test in the micro channel combustor which was fabricated by the wet etching and machining of SUS 304. Using $Pt/Al_2O_3$ coated substrate and Pt coated porous silicon substrate, conversion rate of fuel was over 95 % for $H_2/Air$ premixed gas.

• Bulletin of the Korean Chemical Society
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• 제17권8호
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• pp.696-699
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• 1996

Silicate and borosilicate gels were prepared by the sol-gel process and thermally treated in the 150-850 ℃ temperature range. Solid-state 1H MAS and 29Si CP/MAS NMR spectroscopy were used to investigate the effects of heat treatments on the silicate gel to glass conversion process. The 1H NMR isotropic chemical shifts and the relative intensities of hydrogen bonded and isolated silanol groups have been used to access the information concerning the dehydration process on the silicate gel surface. The 29Si NMR isotropic chemical shifts affected by the local silicon environment have been used to determine the degree of crosslinking, i.e. the number of siloxane bonds. These NMR results suggest that the silicate gel to glass conversion process is occurred by two stages which are dependent on the temperature; (1) the formation of particles up to 450 ℃ and (2) the formation of large particles by aggregation of each separated single particle above 450 ℃. In addition, the effects of B atom on the formation of borosiloxane bonds in borosilicates have been discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.1030-1035
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• 2001

Strontium barium niobate, (Sr$\sub$0.5/Ba$\sub$0.5/Nb$_2$O$\sub$6/), thin films of various composition were prepared by the sol-gel method. Solution derived from acetate powders and niobium ethoxide in a mixture of acetic acid, ethylene glycol and 2-methoxyehanol was spin-coated onto bare silicon, Pt-coated silicon and fused silica substrates. Processing parameters were optimized to develop stable solutions which yielded films with relatively low crystallization temperatures. It was determined that ethylene glycol was a necessary component of the solution to increase stability against precipitation and to decrease the crystallization temperature of the films as confirmed by XRD and FT-IR analyses.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2005년도 추계학술발표회 및 workshop
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• pp.160-163
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• 2005

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1538-1541
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• 2009

Amphiphobic thin films for touched panel application was prepared by $SiO_2$ nanoparticles self-assembled nanostructure. Silicon dioxide nano spheres were prepared by sol-gel method and well dispersed in a solution with surfacants of low surface energy. Nanostrcture thin films were obtained by spin coating technologies.

• The Korean Journal of Ceramics
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• 제6권4호
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• pp.390-395
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• 2000

Silicon, titanium, zirconium phosphates were synthesized by starting with appropriate chemical precursors in a solution. The synthetic procedure, chemical and physical structures were examined by FT-IR, liquid and solid state NMR, TGA, SEM, XRD, etc. The phosphates were examined for thermal and electrical properties. Advantages of the synthesis technique and the data on unique structures and thermal properties are reported.

• Bulletin of the Korean Chemical Society
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• 제9권1호
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• pp.15-17
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• 1988

Titanium tetrachloride is purified using adsorption column packed with activated silica gel. When 120 ml of titanium tetrachloride was passed through an adsorption column filled with 7 g silica gel, iron content in titanium tetrachloride has been reduced from 7 ppm to less than 1 ppm, and aluminum from 46 ppm to 11 ppm, while silicon content being unchanged at about 60 ppm.