• Journal of the Mineralogical Society of Korea
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• v.5 no.2
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• pp.61-71
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• 1992

Through the low-temperature(60-150${\circ}C$) hydrothermal treatment of perlite with the alkaline solution at various NaOH concentrations, the mode of volcanic glass alteration and resultant zeolite formation were investigated in a closed system. At a temperature of 80${\circ}C$ and alkalinities of pH range 8 to 12, corresponding to the natural environments of diagenetic zeolite formation, only weak dissolution of perlitic glass occurs without zeolite formation despite the residence time of 100 days. Activities of Si and Al increase progressively, as a consequence of increasing pH, whereas activity ratios of Si/Al decrease. Zeolites were synthesized from perlite in the alkaline solution at above 0.1M NaOH concentrations. Below the temperature of 100${\circ}C$ Na-P was mainly formed, whereas analcime was the dominant zeolite at the temperature range of 100-150${\circ}C$. During Na-P synthesis chabazite and Na-X were also formed as by-products in case of lower proportion of solution/sample(<10ml/g) and higher NaOH concentraion (>3M), respectively. The alteration modes of perlite in the zeolite synthesis reflect that the formation of synthetic zeolites occurs as an incongruent dissolution likely with the diagenetic formation of natural zeolites from volcanic glass. Considering much difference in reaction kinetics between natural and synthetic systems, however, the evaluated synthetic conditions in these experiments were not directly applicable to the natural diagenetic system.

• Membrane Journal
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• v.2 no.2
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• pp.129-134
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• 1992

The solubility of methane in poly(n-butyl methacrylate)(PnBMA) was determined at pressures up to 35 atm. These measurements were made by volumetric technique in the temperature range from -10 to 30$^{\circ}$C. The solubility was found to be a nonlinear function of the applied pressure and could be satisfactorily described by dual-mode sorption model at temperatures below the glass txansition temperature($T_g$) of the polymer. The Langmuir capacity constant decreased with increasing temperature and vanished near the glass transition temperature of PnBMA. The solubility isotherm became linear at temperatures above the glass transition temperature of PnBMA. The temperature dependence of the dual-mode sorption parameters was also discussed.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.440-448
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• 2005

Physical and chemical properties of waste glass, such as bottle glass, plate glass, and LCD glass were investigated to test the feasibility of starting materials for the production of high quality foamed glass for insulating grade construction material without pre-treatments such as cleaning, and waste removals. For this purpose, chemical analysis, thermal analysis, crystalline analysis, and rheological analysis including viscosity were proceeded and the preparation of foamed glass under the qualitative conditions obtained from these various analysis was also attempted. Overall results of various analysis and investigations for these waste glass showed that waste bottle glass and plate glass have high possivility of use as feed materials for the production of foamed glass.

• Proceeding of KASS Symposium
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• 2008.05a
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• pp.31-36
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• 2008

Architectural membrane are now used in the roof of large span structures throughout the world with the merits of free shape and lightness. Some membrane have some problems of structural capacity by the wind or snow load conditions, large span structures was shown to the tearing of the membrane. This paper is the experimental test on the stress strain curve of cycling load for the glass fiber membrane. In the result of stress strain relationship curve by the cycling load, glass fiber membrane was reduced the tensile strength, the polyester membrane was shown to occur the increase of displacement without load reduction in each load step.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.188-193
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• 2009

유리벌브는 다양한 자동 소화장치 또는 시설에 신뢰성이 높은 감열체로서 각광받고 있다. 당사는 최근 작동온도가 매우 균일하고 하중강도가 우수한 유리벌브를 개발하였고 양산화에도 성공하였다. 본 논문에서는 당사가 개발한 유리벌브의 품질특성을 소개하고자 한다. 특히 본 연구에서는 화재 감지용 감열체로서 유리벌브의 주요 특성치인 반응시간지수 (RTI)에 대해 비중 있는 연구를 진행하여 유리벌브의 RTI를 결정하는 주요 변수들을 도출하고, 이를 설계에 응용하여 유리벌브의 RTI를 조절할 수 있는 툴로서 개발하였다.

• Journal of the Korean Wood Science and Technology
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• v.31 no.5
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• pp.23-34
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• 2003

This study was carried out to investigate the mechanical properties of fabric E-glass fiber reinforced laminated timber. Specimens used to Korean red pine(Pinus densiflora) and Japanese larch(Larix kaemferi). Fabric E-glass fiber was inserted in the solid wood with aqueous polymer-isocyanate resin(MPU-500). The results were as follows: 1. Aqueous polymer-isocyanate resin(MPU-500) was good resin to manufacture laminated timber. specially, it was satisfied to property standard of construction laminated timber(KS F 3021) except for two ply glass fiber. 2. Bending and shear strengths of solid wood inserted with fabric glass fibers were not different from control solid wood. But, proportional limit bending stress was increased following the number of fabric glass fibers. Therefore, it was considered that to improve the bending and shear strength of fabric glass fiber reinforced laminated timber, the glass fiber thickness and its mesh should be modified to fitness following working conditions.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.3
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• pp.41-46
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• 2008

Etching kinetics of $EAGLE^{2000TM}$ LCD glass was investigated using 2.5MHF-xMHCl$(x:0\sim8)$ acid mixtures. It was concluded that the reaction of HF-containing solutions with the glass was the rate-determining step for the dissolution process when considering following observations; the value of the activation energy $35\sim45$ kJ/mol and insensitivity of the dissolution rate to the etching time and the moving velocity of the glass into the solution. The etching rate linearly increased with increasing the HCl concentration in the etchant. It was also observed that the etched surface was as smooth as the original surface by addition of HCl and increase in etching temperature. This is due to the catalytic role of the $H_{3}O^{+]$ ions in the dissolution process.

• Proceedings of the KIPE Conference
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• 2011.11a
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• pp.155-156
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• 2011

겨울철 또는 온도가 낮은 지역에서는 선박과 건축용 등의 창유리에 결로, 결빙현상이 쉽게 발생하여 시야확보가 어렵다. 이 현상들은 창유리의 온도를 상승시킴으로써 방지가 가능하다. 하지만 창유리의 온도는 바람과 기온 및 기후 변화 등의 외란에 민감하므로 일정한 온도 유지가 어렵다. 따라서 민감한 창유리의 온도를 일정하게 유지하기 위한 제어기법이 필요하다. 본 연구에서는 산업현장에 많이 사용되고 있는 PI 제어 기법을 적용하여 4 [kW]급 발열유리 온도 제어 시스템의 제어기를 설계하고 실험을 통하여 제어기의 성능을 검증하였다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.195-195
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• 2003

PDP, FED 등의 디스플레이와 각종 IC 칩부품에 적용 가능한 저융점 유리 프릿 중에서 환경규제가 이루어지고 있는 납성분이 포함되어 있지 않은, Bi계 유리 프릿의 열적 거동 연구를 행하였다. 열처리 온도에 따른 열거동에 따라 프릿의 소성온도 및 미세구조가 결정되므로, 열처리 온도에 따른 유리 프릿의 젖음각을 측정하였고, DTA와 TMA를 통해 유리전이온도, 연화점, 열팽창계수 변화 경향성을 관찰하였다. 본 연구에서 제조된 유리는 조성에 따라 전이온도가 390-50$0^{\circ}C$, 연화점이 400-55$0^{\circ}C$, 열팽창계수가 65-120$\times$10-7/$^{\circ}C$ 범위를 나타내었으며, 고온현미경 측정 결과 Pb-계 유리와 비교시 유사한 열거동을 나타내었다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.147-147
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• 2003

탄소/탄소 복합체의 내산화 코팅을 위하여 산화티탄, 산화알루미늄, 산화이트륨 등을 포함하는 여러 가지 인산염계 유리를 제조하였다. 유리 산화물조성 몰비는 인산에 대하여 인산알루미늄을 15몰%, 30몰%, 45몰%로 하였고 산화티탄은 70몰%, 산화 이트륨은 25몰%이 되도록 코팅 액을 제조하였다. 제조 된 코팅액은 석영 도가니에서 열처리 하여 급냉 시켰으며, 급냉 시키고 다시 130$0^{\circ}C$, 1시간 동안 열처리하여 유리를 제조하였다. 제조된 유리의 열중량, 열팽창율, 열전도도를 분석하여 탄소 복합체와의 적합성을 조사하고, 내산화성 시험을 위해 탄소/탄소 복합체에 코팅액을 도포하여 산화 감량 비율을 측정하였다. 엑스선 회절분석기와 적외선 분광기를 통하여 인산염 유리의 구조분석을 실시하고 비커스 미세 경도 시험기를 이용하여 기계적 물성을 측정하였다.