• Journal of the Korean Ceramic Society
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• v.41 no.12 s.271
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• pp.939-945
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• 2004

Glasses of $SiO_2-B_{2}O_3-Al_{2}O_3-CaO-La_{2}O_3$ with various amounts of $La_{2}O_3$ were infiltrated into a porous alumina to make an alumina-glass composite. The infiltration characterization and bending strength of the composite were examined in terms of glass composition. $La_{2}O_3$ in the glass decreased the high temperature viscosity and this enhanced the wetting behaviour of this glass to alumina, and made glass infiltration easier. The infiltrated glass dissolved the alumina skeleton, and $Al_{2}O_3$ component in the glass melt reprecipitated on the alumina. The grain growth occurred to a specific crystal direction. The glass containing $20mole\%$ of $La_{2}O_3$ was crystallized after infiltration, and this enhanced the bending strength of the composite.

• Journal of the Mineralogical Society of Korea
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• v.28 no.2
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• pp.147-163
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• 2015

Chemical and mineralogical properties of coal ash samples from the nine thermal power plants of Korea were investigated to acquire basic data for estimating the potential of rare metal recovery. Chemical compositions of coal ash were consistent with those of average shale and foreign coal ashes. However, there were small differences between the metal contents of domestic anthracitic and imported bituminous coal ashes. Unburned coal particles were much abundant in the ash of domestic anthracitic coal. Chalcophile elements were relatively enriched in the fly ash compared to bottom ash. Silicate glass was the major component of coal ash with minor minerals such as quartz, illite (muscovite), mullite, magnetite, lime, and anhydrite. Al and Si were the major components of the glass with varying contents of Ca, Fe, K, and Mg. Glass occurred in a form of porous sphere and irregular pumace-like grain often fused with iron oxide spheres or other glass grains. Iron oxide spheres were fine intergrowth of fast-grown iron oxide crystals in the matrix of silicate glass. Chemical, microstructural, and mineralogical properties would guide successful rare metal recovery from coal ash.

• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.29-34
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• 2002

An experiment was conducted to evaluate shattered industrial polyurethane (PUR) and cellular glass foam (CGF) as growth medium components. Pot chrysanthemum 'Pink Pixie Time 'was cuttured in media containing various volume ratios of PUR, CGF, peatmoss, coir, and perlite. Before plant culture, pH and EC of media were determined. Container capacity (%) was low in perlite and CGF-containing media, but it increased when incorporation ratio of peatmoss or coir was increased. pH was stable between 5.0 and 6.3, but was high in coir-contaning media as compared to other media tested. EC was very high in coir-containing media. Hight at 34 days after planting was the greatest in media containing CGF, and number. of leaves was similar among treatments. Growth in PUR-containinly media was poorer than that in the other media, with some leaf edge burning. Trends in growth measured at 97 days after planting was similar to that measured at 34 days after planting.