• 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.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.954-961
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• 2002

Extracts of raw bloody clams, broughton's ribbed ark (Scaphrca broughtonii), subcrenated ark (S. subcrenata), and granulated ark (Tegillarca granosa), were analyzed and compared foe extractive nitrogen, free amino acids, combined amino acids, ATP and related compounds, quaternary ammonium bases, and guanidino compounds. The contents of extractive nitrogen in broughton's ribbed ark, subcrenated ark, and granulated ark were 479, 506, and 432 mg/100 g, respectively. Twenty-eight or twenty-nine types of free amino acids were detected in all three extracts, among which taurine, ${\beta}-alanine$, glutamic acid, and alanine were the major ones. The composition of the major extractive components such as free amino acids, combined amino acids, ATP and related compounds, TMAO, TMA, and creatine in the extracts were similar among the extracts, but their contents were different.

• Journal of the Microelectronics and Packaging Society
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• v.7 no.1
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• pp.7-12
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• 2000

As an essential technology for the FED, VFD and PDP packaging having merits of no glass frit and no glass tube usage, two sodalime glass substrates were electrostatically-bonded in a vacuum environment, and the bond properties were compared with the case of bonding in atmosphere. The glass wafer pairs bonded in vacuum using a-Si interlayer had a relatively lower bond strength than the ones bonded in atmosphere under same bonding conditions (temperature and voltage). And the bond strength was increased in the case of oxygen ambient. Through the XPS and SIMS analyses fur the surface region of a-silicon and bulk glass, it might be concluded that the lower bonding strength was originated from the inactive silicon oxide growth occurred during the electrostatic bonding process due to oxygen deficiency in vacuum.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.239-247
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• 1982

Free and bound lipids of both inner and outer part in the edible portion of 3 varieties of chestnuts(Castanea crenata) were extracted and fractionated into neutral lipid, glycolipid and phospholipid, by silicic acid column chromatography. Fatty acid composition of each fraction was examined with gas chromatography. Lipid contents in chestnut on dry weight basis were 1.84% in inner part(1.26%-free lipid and 0. 58% bound lipid) and 1.95% in outer part (1.63%-free lipid and 0.32%-bound lipid). Free lipid content was $2{\sim}5$ times higher than bound lipid content and was more abundant in the outer part. Neutral lipid content of the free lipid in the inner part was 39.5%, approximately 10 times as much as that of the bound lipid, but in the outer part, the former was 56.6%. Glycolipid content was 22. 0% in the free lipid and 17.0% in the bound lipid. Phospholipid content was 6.9% in the free lipid and 10.5% in the bound lipid. The predominant fatty acids were linoleic acid, palmitic acid and linolenic acid in the free lipid, and palmitic acid, linoleic arid and linolenic acid in the bound lipid, Therefore, saturated fatty acid content in the bound lipid was 2 times higher than in the free lipid.

• Korean Journal of Food Science and Technology
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• v.8 no.4
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• pp.225-229
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• 1976

Gulbi, salted and dried yellow corvenia, is one of widely consuming fish foods in this country. This study was attempted to establish the basic data for evaluating the taste compounds of Gulbi. The free amino acids were analysed by amino acid autoanalyser. In the free amino acid composition of raw yellow corvenia, abundant amino acids were glutamic acid, alanine and lysine and then leucine, glycine, serine and threonine in order. Such amino acids like proline, valine, methionine, tyrosine and phenylalanine were poor in content. The changes of free amino acid composition in the extract of yellow corvenia during Gulbi processing was not observed. In the extract of Gulbi product, glutamic acid, lysine, leucine, alanine and valine were dominant holding 20.0%, 12.9%, 11.1%, 10.1% and 8.5% of total amino acids respectively. The amounts of total free amino acids of yellow corvenia increased more than 3.6 times as compared with that of raw sample during Gulbi processing. It is convinced that the characteristic flavor of Gulbi was attributed to such amino acids like lysine and alanine known as kweet compounds, as glutamic acid with meaty taste, and as leucine known as bitter taste.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.101-104
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• 1981

Changes in free amino acid composition in cotyledon and axis was investigated during growth of soybean sprout. Free amino acid increased with sprout-growth, especially in axis. Arginine, proline and methionine did not appear in axis throughout. Free amino acids in total amino acids was 0.11% for soybean and 8.8% for 8 day-sprout. Free amino acid change in the course of culture was in order of Asp>His>Val>Ile>Thr>Ser>Lys>Tyr>Phe>Leu>Ala>Gly>Pro>Arg>Glu>Met. The content of free amino acid in 4 day-sprout was in order of Asp>Ser>Val>His>Ala>Ile>Lys>Thr>Arg>Leu>Glu>Phe>Tyr>Gly>Cys>Met>Pro.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.148-152
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• 2004

This study was carried out to investigate the callus formation and to determine the composition and contents of the Hee amino acids in seedlings and callus of Rhodiola sachalinensis. The callus formation from the part of seedling-roots was the most effective on MS (Murashige and Skoog) media supplemented with 2.0 mg $L^{-1}$2,, 4-D included in 1.0 mg $L^{-1}$ kinetin than the other experimental plots which prepared with the different concentration of the various growth regulators. Free amino acids extracted from the explants and the callus were a total of 25∼26 kinds. Especially, the basic amino acids such as arginine, lysine and histidine released in callus were found relatively in a large quantity. These results suggest that the cultured callus of Rhodiola sachatinensis could induce for the mass production of the other useful ingredients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.1
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• pp.87-93
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• 1990

The compositions of lipid class and fatty acid of free lipids as non-starch lipid and bound lipids(extraction either at low or high temperature) as starch-lipid extracted from starch in mung bean(phaseolus radiatus L) was investigated. The contents of neutral lipids glycolipids and phospholipids in free lipids were 98.2% 1.7% and 0.1%, whereas those found in bound lipids were 84.3-85.7% 10.5-11.0%, and 5.2-3.3% respectively The major components of neutral lipid fraction in the bound lipids were triglyceride and esterified sterol and those were composed of 0% of total neutral lipids. Monogalactosyl idiglyceride and esteryl steryl glycoside were observed as main glycolipids components in both free and bound lipids. Among the phospholipids in the bound lipids phosphatidylinositol phosphatidyl serine and phosphati-dyl ethanolamine were identified an major constituents. The free lipids contained palmitic(50.2%) stearic(20.6%) oleic(8.5%) and behenic(7.4%) acids and bound lipids had more palmi-tic and linoleic acids but less stearic acid compared to thosed in the free lipids.

• Korean journal of food and cookery science
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• v.14 no.3
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• pp.255-260
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• 1998

The changes in fatty acids and free amino acids of raw and salted-dried flatheads were determined during steaming, boiling and baking process. 1. Raw flathead was composed of 74.9% of moisture, 1.9% of ash, 0.9% of crude lipid, and 21.6% of crude protein. 2. The main fatty acids of raw and salted-dried flathead were palmitic acid (21.5%) and lignoceric acid (52.4%) which covered 73.9% of total fatty acid. The fatty acid contents of raw and salted-dried flathead were higher in the steaming than in the boiling and baking. 3. The main free amino acids of .aw and salted-dried flathead were aspartic acid (12.2%), glutamic acid(14.8%), leuicine (8.4%), Iysine (9.8%) and arginine (6.8%), which covered 52% of total free amino acids. There were significant differences (p<0.05) in the contents of free amino acids between raw and salted-dried flatheads as well as among steaming, boiling and baking processes.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.3 no.2
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• pp.176-184
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• 1993

The glasses, which the $\beta$-spodumene as the principal crystalline phase could be precipitated, were melted by adding >, $P_2O_5, TiO_2, ZrO_2 in the Li_2O-Al_2O_3-SiO_2$ system. In order to achieve the glass-ceramic body of near-theoritical density by sintering method, the optimum condition of heat treatment, the effect of glass powder size and the properties were investigated by DTA, XRD, bulk density, thermal expansion and SEM. Addition of $P_20_5$ imProved the tendency of sintering and the sample with 9wt% $P_20_5$ content was the most dense OOdy by sintering method. The optimum condition of heat treatmemt was sintered for densitification at $740^{\circ}C$ and crystallized at $950^{\circ}C$. In the optimum condition, the relative density was above 90% and the thermal expansion was negative about $-1{\times}10^{-7}/^{\circ}C$.