• Title/Summary/Keyword: 유리조성

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Mineral compositions of the heated coal fly ash (석탄회의 가열에 따른 광물조성 변화)

  • 한경섭;송종택;윤성대;안민선
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.5 no.2
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    • pp.175-180
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    • 1995
  • In order to clarify the part of thermal properties of coal fly ash, the change of mineral compositions of the heated coal fly ash was investigated by XRD, TG - DTA and SEM. It was found that the mineral composition of coal fly ash was quartz, mullite and glassy phase ( a b. 20 ~ 25 wt % ), and had no difference in the range of 105 to $1000^{\circ}C $. Only in the case of Ansan coal fly ash, calcite was detected besides the crystalline of quartz and mullite. And anorthite was produced by the reaction between thermal- decomposed calcite, quartz and $Al_2O_3$component in the glassy phase at $1200^{\circ}C $.

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CHANGES IN FREE AMINO SCIDS OF YELLOW SEA BREAM BRANCHIOSTEGUS JAPONICUS JAPONICUS DURING DEHYDRATION (옥돔건조중의 유리아미노산의 변화)

  • HA Jin-Hwan;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.13 no.1
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    • pp.27-31
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    • 1980
  • Yellow sea bream, Branchiostegus japonicus, has been one of the widely consumed food fish in Jeju-Do, Korea. This study was attempted to establish the basic data for evaluating changes of taste compounds of the yellow sea bream during dehydration. The free amino acids were analysed by amino acid autoanalyser. The free amino acid composition of the raw yellow sea bream, abundant amino acids were lysine, alanine, threonine and arginine and then taurine, serine, proline, glycine, glutamic acid, leucine in order. Such amino acids as valine, methionine, tyrosine, isoleucine, phenylalanine were poor in content. The changes of free anino acid composition in the extract of the yellow sea bream during dehydration was not found. In the extract of dried product, lysine, alanine, glutamic acid and arginine were dominant holding $18.4\%,\;14.7\%\;8.0\%\;and\;7.3\%$ and $7.3\%$ of total amino acids respectively. The amount of total free amino acids of the yellow sea bream increased to more than 1.4 times during dehydration process, that of raw sample especially aspartic and glutamic acids increased to more than 2.9 times and 2. 1 times whereas taurine and histidine decreased ranging $40-50\%$ of the original content. It is presumed that the characteristic flavor of dried yellow sea bream was attributed to such amino acids like lysine and alanine known as sweet compounds, glutamic acid as meaty taste and TMAO known as plain sweet taste.

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Chemical Compositions of Glass Beads from Tombs of Bupwha-ri Site, Yeongdong (영동 법화리유적 출토 유리구슬의 화학적 특성: 토광묘 6호 및 8호)

  • Chung, Kwang-Yong;Kang, Hyung-Tae;Koh, Min-Jeong;Kim, Hwa-Jung
    • Journal of Conservation Science
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    • v.27 no.3
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    • pp.243-250
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    • 2011
  • Seven glass beads from Bupwha-ri site, Yeongdong dated Joseon dynasty were analyzed with SEM/EDS and X-ray diffraction methods. Six samples were classified to potash glass system($K_2O-CaO-SiO_2$) with HCA(High CaO and $Al_2O_3$) and high concentration of MgO suggested raw materials to plant ashes. Especially one sample from tomb no. 8 was highly different concentration of $K_2O$ and MgO with others. It was shown that they were different sources of raw materials. Mostly coloring agents of potash glasses were owing to Fe and Cu. One sample was found to lead glass system(PbO-$SiO_2$) with 12% PbO. The content of PbO was differentiated with other lead glasses since we analyzed so far. It needs more study for compositions of lead glasses with regions and ages.