• 한국안광학회지
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• 제9권2호
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• pp.313-322
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• 2004

유리에는 크게 무기유리와 유기유리로 크게 나눈다. 보통 무기유리를 단순히 유리라 부르고 유기유리는 합성수지 또는 플라스틱이라 부른다. 광학용 플라스틱이라고 불리는 안경용 플라스틱 인 유기렌즈 중 polycarbonate resin이 개발되었는데 이것은 기존 플라스틱렌즈보다도 굴절률이 크고 충격에 강한 우수한 특성을 가지고 있으며 오늘날 널리 이용되고 있는 플라스틱렌즈 소재이다. 본 논문은 polycarbonate resin 안경렌즈 소재에 대해서 자세히 고찰하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1095-1098
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• 2004

In this study, $Bi_2O_3-B_2O_3-ZnO$ glass system, which was expected to have similar properties with PbO containing glass system, was selected as a PbO replaceable potential composition because the atomic weight and ionic radius of Bi is similar to those of Pb. Glasses with different modifier/former ratio were prepared by melting the raw ingredient mixtures in $Bi_2O_3-B_2O_3-ZnO$ system, and the thermal and electrical properties of the sintered samples were examined. The glass transition temperatures and the dielectric constant of the glass pellets were between 350 $^{\circ}C{\sim}$500 $^{\circ}C$ and 15-35, respectively.

• 한국세라믹학회지
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• 제43권1호
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• pp.28-32
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• 2006

Diarylethene in photochromic materials was doped in organic-inorganic hybrid low-melting glasses were synthesized through a nonaqueous acid-base reaction process, which consists of network units including a small number of bridging oxides. The organic phase is a dichlorodimethylsilane while the inorganic phase is a tin(II) chloride. Diarylethene was incorporated into the glasses without any degradation of its functionality. The open form of diarylenthene, which is converted from the opening one upon UV-irradiation, is change to the closed form visible light-irradiation. The rate constant of the photochemical reaction is $31.78\times10^{-3}s^{-1}$ with 400 W UV lamp irradiation.

• 한국세라믹학회지
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• 제39권1호
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• pp.1-11
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• 2002

A bibliographical review of inorganic lithium ion conductors is presented with a focus on those potential candidates for lithium battery application. A wide variety of inorganic lithium ion conductors, both crystalline ceramics and non-crystalline glasses, are considered.

• The Korean Journal of Ceramics
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• 제5권2호
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• pp.183-188
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• 1999

The crystallization behavior and electrical conductivity of the $CuO-Bi_2O_3-V_2O_5$ glasses with various CuO content were investigated. The glass formation regin was 0~20 mol% Bi2O3, 5~55 mol% CuO, and 30~90 mol% $V_2O_5$ with Tg=$275^{\circ}C$~$290^{\circ}C$. Among glasses with various compositions, the 31CuO-$14Bi_2O_3-55V_2O_5$ (mol%) glass heat-treated at $358^{\circ}C$ for 8 h showed the highest conductivity of ~ at room temperature. The heat-treated glasses increased in electrical conductivity by the order of 104 compared to non heat-treated glass. The linear relationship between 1n($\sigma$T)and $T^{-1}$ indicated that electrical conduction in the 31CuO-$14Bi_2O_3-55V_2O_5$ (mol%) glass occurred by a small polaron hopping.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1099-1102
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• 2004

For the development of Pb-free low temperature sintering glass frits, $BaO-B_2O_3-SiO_2$ system was examined. The content of BaO and $B_2O_3$ was changed when the content of $SiO_2$ was fixed to 10 mol%. When the content of BaO was more than 60 mol% devitrification was observed. In the sintering temperature range between 520${\sim}$620 $^{\circ}C$, the optimum sintering temperature decreased as the content of BaO increased. When BaO ${\geq}$45 mol%, the glasses were crystallized after sintering. Candidate compositions are suggested in $BaO-B_2O_3-SiO_2$ system, which can replace the PbO containing glass system.

• The Korean Journal of Ceramics
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• 제5권4호
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• pp.336-340
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• 1999

Glasses in the system $CaO-TiO_2-SiO_2-Al_2O_3-ZrO_2-B_2O_3$ were investigated to find the glass seal compositions suitable for use in the planar solid oxide fuel cell (SOFC). Glass-ceramics prepared from the glasses by one-stage heat treatment at $1,000^{\circ}C$ showed various thermal expansion coefficients (i,e., $8.6\times10^{-6^{\circ}}C^{-1}$ to $42.7\times10^{-6^{\circ}}C^{-1}$ in the range 25-$1,000^{\circ}C$) due to the viscoelastic response of glass phase. The average values of contact angles between the zirconia substrate and the glass particles heated at 1,000-$1,200^{\circ}C$ were in the range of $131^{\circ}\pm4^{\circ}$~$137^{\circ}\pm9^{\circ}$, indicating that the glass-ceramic was in partial non-wetting condition with the zirconia substrate. With increasing heat treatment time of glass samples from 0.5 to 24 h at $1,100^{\circ}C$, the DC electrical conductivity of the resultant glass-ceramics decreased from at $800^{\circ}C$. Isothermal hold of the glass sample at $1100^{\circ}C$ for 48h resulted in diffusion of Ca, Si, and Al ions from glass phase into the zirconia substrate through the glass/zirconia bonding interface. Glass phase and diffusion of the moving ion such as $Ca^{2+}$ in glass phase is responsible for the electrical conduction in the glass-ceramics.

• 한국세라믹학회지
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• 제39권3호
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• pp.265-271
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• 2002

용융법으로 제작된 인산염 유리시편의 조성변화에 따른 밀도와 물에 대한 안정성 및 각각의 구조변화를 조사하기 위해 Raman과 적외선 흡수 스펙트럼이 측정되었다. 그 결과 $P_2O_5$가 60mol% 부근에서 밀도와 물에 대한 안정성이 급격히 증가하는 구조적인 이상성을 나타내었다. 이러한 변화는 $Mg^{2+}$ 이온을 중심으로 DBO(Double-Bonded Oxygen)이 배위하면서 유리구조의 강한 수축을 유발시켜 나타난 구조변화에 기인하는 것으로, $Mg^{2+}$ 이온을 배위하고 있는 DBO은 이중결합의 성격을 잃어버리고, 다른 하나의 NBO(Non-Bonding Oxygen)과 함께 공명구조를 이룬다고 생각된다.

• 자연과학논문집
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• 제8권1호
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• pp.47-51
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• 1995

알루미나와 Hydroxyapatite(HAp)의 결합을 연구하기 위하여 9 가지의 중간 유리상을 연구하였다. 그 중간상의 화학 조성은 $CaO-Al_2O_3$에서 정하였으며 CaO/$Al_2O_3$의 몰 비율은 0.5에서 3 까지 변화 시켰다. 가장 낮은 용융은 CaO/$Al_2O_3$의 몰 비율이 2이고 $1355^{\circ}C$때 나타났다. $Al_2O_3$의 양을 증가시킴에 따라 용융점은 점점 높아 졌고 많은 기공들이 발견 되었다. 단면 조직 조사에 따르면 높은 CaO양 시편에서 양호한 흡수접착을 발견할 수 있었고, 이것은 CaO/$Al_2O_3$ 비가 2보다 큰것에서 더좋은 흡수접착을 얻을 수 있음을 의미한다. 열처리후 상변태는 발견되었으나, HAp의 중요한 피크는 그대로 남아 있음을 알 수 있다.

• 한국세라믹학회지
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• 제31권9호
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• pp.957-968
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• 1994

Manufacturing process of porous glass by the filler method was studied. Commercial soda-lime-silicate glass powder was mixed with inorganic salt as the filler such as KCl, K2SO4, Na2SO4. Sintering shrinkages of mixed powders with the variation of sintering temperature were compared, and the effects of the fillers to shrinkages of mixed powder were increased in the order of Na2SO4${\mu}{\textrm}{m}$ of pore diameter were manufactured when the filler sizes 100~200 ${\mu}{\textrm}{m}$. The open pore volume of porous glass is determined by the quantity of filler and porous glasses having open pore volume between 30 and 70 vol% are available. Available sintering temperature range for preparation of porous glass is from the softening temperature of the glass powder to eutectic melting temperature of DTA curve of mixed powder.