• Bulletin of the Korean Chemical Society
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• 제18권7호
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• pp.740-743
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• 1997

The ionic conductivity of several simulated borosilicate glasses was measured in the temperature range 150-600℃ in air. Leaching experiments were also carried out using Soxhlet apparatus at 100 ℃ for 7 days. As Li+ ion increased in simulated borosilicate glasses, both the ionic conductivity and leaching rate increased. The activation energy in the ionic conduction of the simulated borosilicate glasses was 1.38-1.45 eV in the high temperature region and 0.93-1.1 eV in the low temperature region.

• 공업화학
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• 제2권3호
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• pp.289-299
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• 1991

후막 구리도체에 적합한 유리를 얻기 위하여 연붕규산계 및 무연 붕규산계 유리를 기반으로 하는 9종의 유리를 제조하고 후막 구리도체에의 적합성을 시험하였다. 그 결과 모든 유리들이 후막 구리도체의 쉬트 저항치, 납땜성 및 땜납 침식저항에는 양호하게 기여하는 것을 확인하였다. 그러나 후막과 알루미나 기판간의 노화후의 부착강도는 연붕규산계 유리로 만들어진 구리 도체막 만이 유용한 값을 가졌고, 그 외의 유리로 만들어진 구리 도체막의 노화후 부착강도는 사용하기에 부적합할 정도로 낮은 것이었다. 특히 $Cu_2O$ 가 첨가된 연붕규산계 유리가 후막 구리도체 제조에 가장 양호한 것으로 확인되었다.

• 한국세라믹학회지
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• 제34권8호
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• pp.886-896
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• 1997

To investigate an effect of phase separation on precipitation characteristics of CuCl nanocrystals in CuCl doped nonlinear optical glasses, borosilicate glass systems with 9 different compositions with ~2wt% of CuCl were selected and CuCl doped glasses were prepared by melting and precipitation method. Microstructural properties of the CuCl doped glasses were analyzed by optical absorption spectroscopy, acid elution test, TEM, and EDXS. While phase separation did not occur in Glass A~D, interconnected and droplet microstructures due to phase separation were found in Glass E, F and Glass G~I, respectively. In the particular composition of the matrix glasses in this study, the precipitation of the CuCl particles was observed in the phase separable glasses, not in phase non-separable glasses. The CuCl particles were precipitated in both silica-rich phase region and boronrich phase region of the glass matrix. In the case of 7.7Na2O-36.6B2O3-52.7SiO2(mole%) glass, the larger CuCl particles than those in the silica-rich phase region were observed in the boron-rich phase region.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.266-269
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• 2003

심부 처분환경조건에서 붕규산유리고화체의 장기침출거동을 규명하기 위하여 3종의 모의붕규산유리고화체에 대한 장기침출실험이 1997년에 착수되었다. 5년간의 침출결과는 붕소가 본 붕규산유리고화체의 장기침출지표물질로 사용될 수 있음을 확인시켜 주었고, 비록 고화체들의 조성은 약간씩 다르지만 초기 1년여 기간동안의 침출률을 제외한 장기침출률은 S/V에도 무관하게 $0.03g/m^2-day$에 근접함을 보여주고 있다.

• Nuclear Engineering and Technology
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• 제49권1호
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• pp.216-223
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• 2017

In this work, linear and mass attenuation coefficients, effective atomic number and electron density, mean free paths, and half value layer and $10^{th}$ value layer values of barium-bismuth-borosilicate glasses were obtained for 662 keV, 1,173 keV, and 1,332 keV gamma ray energies using MCNP-4C code and XCOM program. Then obtained data were compared with available experimental data. The MCNP-4C code and XCOM program results were in good agreement with the experimental data. Barium-bismuth-borosilicate glasses have good gamma ray shielding properties from the shielding point of view.

• 방사성폐기물학회지
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• 제1권1호
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• pp.41-46
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• 2003

심부 처분환경조건에서 붕규산유리고화체의 장기침출거동을 규명하기 위하여 3종의 모의붕규산유리고화체에 대한 장기침출실험이 1997년에 착수되었다. 5년간의 침출결과는 붕소가 본 붕규산유리고화체의 장기침출지표물질로 사용될 수 있음을 확인시켜 주었고, 비록 고화체들의 조성은 약간씩 다르지만, 초기 1년여 기간동안의 침출률을 제외한 장기침출률은 S/V에도 무관하게 0.03g/$m^2$-day 에 근접하는 경향을 보여주고 있다.

• 한국세라믹학회지
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• 제26권4호
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• pp.521-531
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• 1989

The dependence of the chemical durability of simulated waste glasses containing the simplified waste similar to the SRP waste on compositions of host glasses, amounts of waste loading, and kinds of leachants has been investigated as a basic study on the waste immobilization through vitrification. The maximum limit of the amount of waste loading for glassforming with the host sodium borosilicate glasses selected in this study was 50wt%. The chemical durability of waste glasses whose host glass belonged to the immiscible composition region was much higher than that of waste glasses whose host glass belonged to the miscible composition region. The former waste glass showed lower chemical durability in deionized and silicate waters than in brine, while the latter glass showed the lowest chemical durability in deionized and silicate waters than in brine, while the latter glass showed the lowest chemical durability in silicate water. It was also observed that the total leaching rates in brine were noticeably small in comparison with those in other solutions. The composition of the host borosilicate glass which was suitable for the treatment of the waste through vitrification was found to be 25 Na2O-5B2O3-70SiO2(wt.%).

• 한국세라믹학회지
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• 제35권12호
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• pp.1337-1342
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• 1998

To investigate an effect of phase separation on precipitation characteristics of ZnS microcrystals in ma-trix glass ZnS doped borosilicate glasses for nonlinear optical applications were prepared by melting and pre-cipitation process. ZnS dopant contributed to phase separation promotion which increased the phase separa-tion of the matrix glass within immiscibility region. It was also found that ZnS as phase separation promoter showed a similar contribution for some selected glass compositions in miscibility region. The precipitation of ZnS microcrystals occurred in thephase separable glass compoitions. The radius of ZnS microcrystals in-creased with increasing the heat treatment temperature and Na2O contents of matrix glass composition. The ZnS particle sizes estimated by effective mass approximation ranged from about 30 to 80${\AA}$ It was suf-ficiently small to show quantum confinement effect.

• 한국세라믹학회지
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• 제48권3호
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• pp.222-227
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• 2011

The hexavalent chromium ions in wastewater are highly toxic chemicals even at low concentrations. It causes serious diseases, such as cancer, skin disease, digestive trouble et. al. In this study, $Cr^{6+}$ ions were removed by using borosilicate glasses. Various glasses system with different compositions were prepared and then reacted in a solution contaning $Cr^{6+}$ ions. After the reaction, the concentration of the $Cr^{6+}$ ions remained in the solution was measured by ICP-OES. The reacted surface of the glasses was also analyzed by using a XRD, SEM, and EDS. When $Na_2O-RO-SiO_2-B_2O_3$ (RO=MgO, CaO, SrO, BaO) glasses were reacted with a solution containing $Cr^{6+}$ ions, the optimum removal efficiency of $Cr^{6+}$ ions was observed in the BaO glass. $Ba^{2+}$ ions leached out of these glasses combine with $Cr^{6+}$ ions in a solution to form $BaCrO_4$ crystals on the glass surface. In this manner, the $Cr^{6+}$ ions can be removed from the solution. It is conceivable that $Ba^{2+}$ ions are reacted with $Cr^{6+}$ ions in a solution immedeately after leaching out of the glasses. The pH of the solution for optimum removal of $Cr^{6+}$ ions were 3.0~5.0.

• The Korean Journal of Ceramics
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• 제1권2호
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• pp.96-100
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• 1995

Recently, alumina/glass composites have been applied as a substrate material for hybrid IC and LSI multi-chip packaging. In this study, the characterization of sodium borosilicate glasses containing NaF and $AlF_3$ and the preparation of the resulted glass/alumina composites have been examined and the effect of the addition of fluorides on the thermal. and dielectric properties of the sintered composites have been studied. The sintering temperature of specimens was lowered by about 100-$150^{\circ}C$ by the addition of fluorine compared with the specimens without fluorine. The specimens containing fluorine showed slightly lower dielectric constants than those of the specimens without fluorine.