• Title/Summary/Keyword: Inorganic glasses

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Review of the Polycarbonate (Polycarbonate의 고찰)

  • Choi, Gei-Hun
    • Journal of Korean Ophthalmic Optics Society
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    • v.9 no.2
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    • pp.313-322
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    • 2004
  • Glasses are to be classified in organic glasses and inorganic glasses. Generally, we just call glasses instead of calling inorganic glasses and call synthetic resin or plastic instead of calling organic glasses. One of the ophthalmic plastic glasses develops into polycarbonate resin in organic glasses. Recently, polycarbonate resin is widely known because it has larger index and impact than plastic lens. Ours study analyzed about polycarbonate resin in ophthalmic substance.

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Thermal and electrical properties of $Bi_2O_3-B_2O_3-ZnO$ glasses for the application to plasma display panel

  • Kim, Byung-Sook;Lim, Eun-Sub;Lee, Joon-Hyung;Kim, Jeong-Joo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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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.

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Photochromism of Diarylethene-Doped Organic-Inorganic Hybrid Low Melting Glass (Diarylethene이 첨가된 저융점 유-무기 하이브리드 유리의 광변색 특성)

  • Kim, Ji-Kyung;Kim, Myeong-Jeong;Park, Sung-Je;Ryu, Bong-Ki
    • Journal of the Korean Ceramic Society
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    • v.43 no.1 s.284
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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.

Preparation and Electrical Conductivity of CuO-Bi2O3-V2O5 Glass for Solid State Batteries

  • Jeong, Dong-Jin;Park, Hee-Chan;Lee, Heun-Soo;Park, Chan-Young
    • The Korean Journal of Ceramics
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    • v.5 no.2
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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.

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Characterization of $BaO-B_2O_3-SiO_2$ glass for the application to PDP;Effect of BaO/$B_2O_3$ ratio

  • Lim, Eun-Sub;Kim, Byung-Sook;Lee, Joon-Hyung;Kim, Jeong-Joo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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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.

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Properties of Glass-Ceramics in the System CaO-TiO2-SiO2 with the Additives of Al2O3, ZrO2 and B2O3 for Use in the Solid Oxide Fuel Cells.

  • Lee, Jun-Suk;Park, Min-Jin;Shin, Hyun-Ick;Lee, Jae-Chun
    • The Korean Journal of Ceramics
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    • v.5 no.4
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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.

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Abnormality of P2O5-Na2O-MgO Glasses by Raman and Infrared Spectroscopy (라만과 적외선 분광기를 이용한 P2O5-Na2O-MgO 유리의 이상성에 관한 연구)

  • Lee, Byung-Chul;Kwon, Young-Jun;Ryu, Bong-Ki
    • Journal of the Korean Ceramic Society
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    • v.39 no.3
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    • pp.265-271
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    • 2002
  • Density, water resistance, Raman and infrared spectroscopy were used to investigate the change of structural characteristics with the composition of phosphate galss samples made by melting method. The structural abnormality of the density and water resistance were rapidly increased and shown near the 60mol% of $P_2O_5$. This result could be explained by the structural changes owing to the strong shrinkage of glass network by the coordination of DBO(Double-Bonded Oxygen) around $Mg^{2+}$ cations. In addition, it seems that the DBOs coordinating $Mg^{2+}$ cations lose its characteristics of double bonding and resonate with other NBOs(Non-Bonding Oxygen).

THE INTERMEDIATE GLASS STUDY IN HYDROXYAPATITE AND ALUMINA BONDING (HAp와 알루미나 결합에 있어서의 중간 유리상 연구)

  • Kim, T.N.;Kim, J.O.;Cho, S.J.
    • The Journal of Natural Sciences
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    • v.8 no.1
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    • pp.47-51
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    • 1995
  • Several intermediate glasses are investigated to bond the alumina and the hydroxyapatite (HAp). The chemical compositions of the intermediate glasses are chosen as $CaO-Al_2O_3$. The mole ratio of CaO/$Al_2O_3$ is changed from 0.5 to 3.0. The lowest melting is observed at $1355^{\circ}C$ in the specimen of CaO/$Al_2O_3$ at the mole ratio of 2. With increasing contents of $Al_2O_3$, the melting temperatures gradually increase and a number of pores are observed. The sectional microstructure shows that the good wetability is observed in higher contents of CaO specimens. This implies that the good wetability is obtained in the mole ratio range of CaO/$Al_2O_3geq2$. The phase transformations are observed after treatment but the major peaks of HAp still exist.

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Preparation of Porous Glass by the Sintering (소결법에 의한 다공질유리의 제조)

  • 박용완;이준영
    • Journal of the Korean Ceramic Society
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    • v.31 no.9
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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.

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