• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.120-121
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• 2021

The organic insulation material has excellent thermal insulation property, but it is difficult to expect fire stability, and semi inorganic insulation only delays combustible hour but it is difficult to expect fire stability. In this study, thermal insulation property of cement-based non-combustible inorganic insulation using cement and non combustible materials and redispersible polymer powder was studied. As a result of the experiment, the thermal insulation property decreased as the use of redispersible polymer powder increased, but the heat insulation property improved when using the appropriate amount.

• Journal of the Korean Ceramic Society
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• v.43 no.1 s.284
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• pp.1-3
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• 2006

Well-shaped NaA zeolite cubic crystals of a large size of $5-7{\mu}m$ were synthesized by a hydrothermal method in a mother solution having a $3.55Na_2O:Al_2O_3:1.6SiO_2:593\~2000H_2O$ composition. Thermal treatment of NaA zeolite crystals resulted in the formation of a crystalline phase of $NaAlSiO_4-Camegeite$ between 800 and $900^{\circ}C$. Even at $1000^{\circ}C,\;NaAlSiO_4$ phase was found as a major product. Environmental Scanning Electron Microscopy (ESEM), High Resolution Transmission Electron Microscopy (HRTEM), X-Ray powder Diffraction (XRD), Fourier Transform Infrared (FT-IR) spectroscopy, and DTA/TGA and BET analyses were used to characterize the initial materials and the obtained products after various heat treatments.

• The Korean Journal of Ceramics
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• v.7 no.1
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• pp.1-5
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• 2001

Inorganic-organic hybrid Li$^+$ ion conductors were prepared by the sol-gel process. Tetramethyl orthosilicate (TMOS), polyethylene glycol 200 (PEG$_200$) and lithium bis (trifluoro-methylsulfony) imide were used as raw materials and $H_2O$ was used as a solvent. Hybrid Li$^+$ ion conductor prepared by the sol-gel process showed very high ion conductivities of log${\sigma}_R.T$(S/cm)=-3.73, log${\sigma}_60$(S/cm)=-3.00 at room temperature and $60^{\circ}C$, respectivery. Decomposition voltage was 3.1 V.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1323-1326
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• 1994

the application of epoxy composite materials for outdoor insulating systems has some significant advantages compared with conventional inorganic materials, that is low weight in combination with high mechanical strength, small dimensions and design versatility. The experimental results for the basis composition and interlace characteristics of the matrix resin/inorganic fillers($SiO_2$) which are the composite materials have been studied. The electrical characteristics(electrical breakdown, dielectric, insulating resistivity, tracking) and mechanical characteristics( tensile strength, elongation, flexible strength) in the epoxy composite materials have been studied. The life of the epoxy composite material was evaluated by accelerated Weather-Ometer test and the degradation process due to outdoor exposure condition is discussed with respect to the mechanical and electrical properties.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.94.4-94
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• 1998

• Korean Chemical Engineering Research
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• v.44 no.3
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• pp.254-258
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• 2006

Zeolites with excellent adsorption capacity of volatile organic compounds were attached onto inorganic fibers which were the raw materials of honeycomb-type adsorbers. The amounts of zeolite particles attached onto the fibers considerably increased by treating them with hydrochloric acid, sulfuric acid, or hydrofluoric acid. Various functional groups such as chloropropyl, aminopropyl and epoxy groups of silane compounds, and amine groups of polyethylenimine were employed as covalent linkage materials between the fibers and zeolite particles. The state of the fibers coated with zeolite particles was examined by scanning electron microscopy, and the amounts of zeolite particles bound to the fibers were estimated from their BET surface areas. The largest amount was obtained when polyethylenimine was employed as a linkage material. Polyethylenimine was the most effective for attaching zeolite particles onto the inorganic fibers among various linkers employed.

• Journal of the Korean Ceramic Society
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• v.28 no.9
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• pp.667-674
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• 1991

In this study, Kaolin was carbonized at 1300~175$0^{\circ}C$ and its constituent mineral change was investigated. Carbonized kaolin at 1$650^{\circ}C$ was mixed with metallic silicon, formed and nitrified at 135$0^{\circ}C$ in N2-NH3 atmosphere. Properties of this product such as porosity, bulk density, MOR, nitrization rate and oxidation resistence were measured, and its mineralogical changes were investigated by XRD. The results were as follows; 1) $\beta$-SiC was initially synthesized at 150$0^{\circ}C$, and its amount was continuously increased with reaction temperature to 1$700^{\circ}C$. 2) At 1$600^{\circ}C$, mullite was rapidly decomposed and the amounts of $\beta$-SiC and $\alpha$-Al2O3 were increased simultaneously. 3) By adding alkali to kaolin, the decomposition temperature of mullite was dropped approximately 10$0^{\circ}C$, but the amount of $\alpha$-SiC was increased. 4) The highest values of their nitrization rate and MOR were obtained at the specimen of 35 wt% metallic silicon in nitrization reaction. 5) It seems that increment of $\alpha$-Si3N4 and $\alpha$-Al2O3 phase during nitrization was due to the decomposition of Al4SiC4 existed in carbonized kaolin. 6) Si3N4 bonded SiC-Al2O3 composite were fabricated from kaolin at relatively low temperature (135$0^{\circ}C$).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.5
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• pp.222-226
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• 2006

Effects of a carboxylated styrene-butadiene-based liquid additive on the microstructure, mechanical strength and decolorization resistance of inorganic pigment layer in the color block have been examined. More dense inorganic pigment layer characterized by lower apparent porosity, lower water absorption and uniform pigment distribution has been achieved by incorporation of a liquid additive. Also significant enhancements in the mechanical strength and decolorization resistance have been observed.

• 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.

• Journal of the Korean Ceramic Society
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• v.42 no.2 s.273
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• pp.110-116
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• 2005

Suitable compositions which are sinterable at low temperature in the $BaO-B_{2}O_{3}-ZnO$ glass system were investigated as a function of the ratio between BaO and ZnO. The effect of $Al_{2}O_3$ filler on densification and physical characteristics of the glass was also examined. When the amount of $Al_{2}O_3$ filler increased, the densification rate and the values of dielectric constant, thermal expansion coefficient and hardness in the glass-filler composites decreased gradually. The decreasing rate of the physical properties accelerated when fine $Al_{2}O_3$ filler was used. However, the fracture toughness of the composite rather increased due to the existence of filler particles and pores which effectively suppressed crack propagation with addition of fine $Al_{2}O_3$ filler.