• 한국세라믹학회지
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• 제25권4호
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• pp.315-320
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• 1988

The Nb doped BaTiO3 was synthesized by coprecipitation method using H2O2 media in region from pH 8 to pH 11. The powder prepared by using this method was crystallized at about 20$0^{\circ}C$ and average particle size was controlled by heat treatment. Because of preparation having fine particle and relatively narrow particle size distribution, high performance PTC device was made of these precipitated powders.

• 한국세라믹학회지
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• 제26권5호
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• pp.677-681
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• 1989

On the preparation of silica glass by sol-gel process, we used fine powder of silica gel to prevent cracking. In this case, the best condition of silica glass preparation is the contents of 10~40wt% seed and the gelation time of solution in contract. The dried gels conversed to silica glass by heat treatment up to 125$0^{\circ}C$.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 1998년도 춘계 학술발표회 논문집
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• pp.173-176
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• 1998

FCC (Fluid Catalystic Cracking) 장치는 중질유의 원유와 잔사유로부터 가솔린과 heating oil. 디젤연료 제조 등에 사용되고 있다. 이 장치는 50년 동안 fine-powder 유동화에 중요하게 응용되고 있으며, 현재 세계적으로 약 350여 개의 장치가 조업되고 있다. FCC 장치에서 미세한 분해촉매는 촉매에 의한 중질유의 분해가 일어나는 상승관 (riser)과 촉매의 재생이 일어나는 재생반응기(regenerator) 사이에서 높은 속도로 순환되고 있다. (중략)

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.31-35
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• 2003

High-Flowability Concrete has many advanced properties and been focused on their workability. Because of the difficulty in understanding of the quality of High-Flowablity Concrete just using slump properties, many studies have been carried out rheological properties influenced on concrete fluidity. In this paper, for the purpose of expecting some level of rheological properties, the change of rheological properties of High-Flowability Concrete with dosages and types of superplasticizer, and various addition amounts addictives were investigated.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.19-24
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• 1995

Most difficulties in inducing high flowability of general strength concrete arise from the segregation of aggregates due to the shortage of cementatious binders. To solve the problem, our research team has concentrated on finding the binders to link a gap between coarse and fine aggregates, under the condition not to influence a concrete strength. As a result of using stone powder or a middle class of aggregate size mostly used for asphalt pavement(Max. dia 13mm), we found that flowability of concrete increased significantly without aggregation and decrease of compressive strength.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회 논문집(I)
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• pp.111-116
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• 1998

This studies regarding development of product system on artificial aggregate using of Paper Sludge Ah that waste production at paper-making mill, expecially this paper describes development of product system using centrifugal mixer plant. The skills of this product system on artificial aggregate using of Ash can be spread Fly-Ash, powder and fine aggregate(under 5mm) of waste concrete reuse.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.69-75
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• 1997

This studies regarding deveolpment of product system on artificial aggregate using of Paper Sludge Ash that waste production at paper-making mill. Expecially this paper discribes development of product system using centrifugal mixer plant. The skills of this product system on artificial aggregate using of Ash can be spread Fly-Ash, powder and fine aggregate (under 5mm) of waste concrete reuse.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1240-1241
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• 2008

Superconducting ceramics of YBaCuO was fabricated on SrTiO substrate by chemical fabrication method using fine powder of YBaCuO having diameter less than 1um. The pattern of the fabricated superconducting bulk was linear and the thickness of it can be controlled in the range of 50um. The structure of the surface of film by diffraction pattern and composition. The tape like YBaCuO bulk with width of 10mm was formed on substrate using similar method. Tape like film is expected to utilize as material of superconducting tape.

• 한국세라믹학회지
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• 제29권5호
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• pp.367-376
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• 1992

The powder characteristics of seeded alumina prepared from alkoxide by sol-gel method were studied. When ${\alpha}$-Al2O3 seeded powders used, these ${\alpha}$ phase transformation temperatures decreased than those of unseeded powders by 110$^{\circ}C$ and fine powders under 0.1 $\mu\textrm{m}$ could be obtained. When Fe-nitrate added powders used, fast transformation rate resulted from ionic effects of Fe3+, but hard aggregated morphology exhibited. When ${\alpha}$-Al2O3 and Fe nitrate simultaneously added, these powders represented lower transformation temperature but resulted in microstructure with aggregated particles.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.440-442
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• 1997

The properties of magnetic suppositories used in medicine has been tested with M ssbauer spectroscopy methods. The experiments were carried out on magnetic rectal suppositories containing parmadine and fine-dispersed ferrite powder BaO.nFe$_2$O$_3$as a magnetic filler. According to the data on the value of effective magnetic field on $^{57}$ Fe nuclei in ferrite magnetic sublattices, the stoichiometric n-number equals approximately 5.5; this vague corresponds to the composition range of optimal magnetic properties.