• Journal of the Korean Magnetics Society
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• v.4 no.1
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• pp.62-68
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• 1994

Water-based magnetic fluids containing synthesized ultrafine magnetite were successfully prepared with $C_{18}$ fatty acid such as oleic acid, linoleic acid and stearic acid. Oleic acid was needed the amount of $3.0{\times}10^{-2}$ mol per 20 g magnetite to stabilize the magnetite $d\;=\;113\;\AA$ particles. From pH 8.0 to pH 11.0, stable aqueous-based fluids could be obtained. The aggregated powder after drying the water-based magnetic fluid was also successfully re-dispersed in dilute $NH_{4}OH$ solution and in kerosene. The pH levels of the magnetic fluid using oleic acid system could be predicted by the pH values obtained by calculation of therrrodynamic data.

• Journal of Powder Materials
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• v.18 no.6
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• pp.546-551
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• 2011

Ag spot-coated Cu nanopowders were synthesized by a hydrothermal-attachment method (HA) using oleic acid capped Ag hydrosol. Cu nano powders were synthesized by pulsed wire exploding method using 0.4 mm in diameter of Cu wire (purity 99.9%). Synthesized Cu nano powders are seen with comparatively spherical shape having range in 50 nm to 150 nm in diameter. The oleic acid capped Ag hydrosol was synthesized by the precipitation-redispersion method. Oleic acid capped Ag nano particles showed the narrow size distribution and their particle size were less than 20 nm in diameter. In the case of nano Ag-spot coated Cu powders, nanosized Ag particles were adhered in the copper surface by HAA method. The components of C, O and Ag were distributed on the surface of copper powder.

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.930-934
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• 2005

A chloroform membrane system containing a given mixture of benzylaza-12-crown-4 and oleic acid is introduced for the selective and efficient transport of $Pb^{2+}$ ion. The transport was capable of moving metal ions ‘up-hill’. In the presence of ${S_2O_3}^{2-}$ion as a suitable metal ion acceptor in the receiving phase, the amount of lead ion transport across the liquid membrane after 150 minutes is (95.0 ${\pm}$ 1.7)%. The selectivity and efficiency of lead transport from aqueous solution containing $Tl^+,\;Ag^+,\;Mg^{2+},\;Ca^{2+},\;Co^{2+},$ $Ni^{2+},\;Cu^{2+},\;Zn^{2+},\;Hg^{2+}$ and $Cd^{2+}$were investigated. In the presence of thiosulfate as a suitable masking agent in the source phase, the interfering effects of $Ag^+\;and\;Cu^{2+}$ were diminished drastically.

• Journal of Ginseng Research
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• v.8 no.1
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• pp.38-44
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• 1984

In order to investigate the influence of gamma-irradiation on fatty acids in ginseng, ginseng were irradiated with various radiation doses(0-50 Mrads). The results are as follows. 1. With increasing dose, standard fatty acids were decreased in the order of linolenic acid, linoleic acid and oleic acid, and their contents in the presence of oxygen were decreased more t than that in the absence of oxygen. 2. Changes of lipid content in white ginseng by gamma irradiation were varied with the samples, but the changes of crude lipid and purified lipid in a sample were showed same fashion. 3. The fatty acid contents in white ginseng were decreased by gamma irradiation in the order of linolenic acid, linoleic acid, oleic acid, stearic acid and palmitic acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.238-243
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• 1994

Changes of lipid components in modified oleoresin during cooking at high temperature were investigated. In preparation of the modified oleoresin, dried red pepper was milled to 100 mesh of size particle and extracted oily compounds by reduced pressure steam distillation . The rest part was reextracted and concentrated and concentrated. The extracts were combined. The same volume of water and 4% of polyglycerol condensed ricinoleate (PGDR) were added to the combined extract, and emulsified to make oleresin red pepper. Non-polar lipid components were quantified 3 times higher in the oleoresin than polar lipid components . The components of non-polar lipd was mainly triglyceride comprising 75.8%. The level of phosphatidyl choline and phosphatidyl ethanolamine were 38.6and 26.1%, respectively. linoleic acid was distinctively abundant (63.1%) and followed by palmitic acid, oleic acid, linolenic acid and stearic acid in the oleoresin. Oxidation of lipid at high temperature was principally affected by temperature rather than oxygen existence . With the result of oxidation , palmitic acid and myristic acid increased, however, oleic acid, linoleic acid, and linolenic acid decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1806-1812
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• 2015

This study was conducted to compare moisture, crude protein, ether extracts, fatty acid composition, and melting point of beef with different origins. Eighty (80) samples of domestic Hanwoo beef with different marbling scores (BMS) of 3, 5, 7, and 9, respectively (20 samples for each BMS) and 30 samples of imported beef (15 samples each of American and Australian beef) were used. Relationship of fatty acid composition with melting point of lipids was also analyzed. Percentages of ether extract of Hanwoo beef with BMS of 3, 5, 7, and 9 as well as American and Australian beef were 11.91, 13.23, 17.03, 23.92, 8.36, and 4.47%, respectively, with the highest value in Hanwoo with BMS of 9 and lowest value in Australian beef. Percentages of oleic acid (C18:1n9), the most abundant monounsaturated fatty acid (MUFA) in beef, were 44.92, 47.19, 46.23, 47.70, 43.70, and 38.28%. MUFA/saturated fatty acid (SFA) (M/S) ratios were 1.15, 1.25, 1.22, 1.27, 1.10, and 0.86, respectively. The melting point of lipids extracted from beef samples was the lowest ($27.42^{\circ}C$) in Hanwoo with BMS of 9, whereas it was highest ($41.15^{\circ}C$) in Australian beef. SFAs such as myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), and total SFA in beef samples showed positive (+) correlations (r=0.203, 0.279, 0.807, and 0.880, respectively) with melting points, whereas MUFAs, palmitoleic acid (C16:1), oleic acid (C18:1n9), and total MUFA, showed negative (-) correlations (r=-0.541, -0.857, and -0.906, respectively). In conclusion, as the lipid contents of beef increased, composition of oleic acid (C18:1n9) increased. Furthermore, as BMS increased in Hanwoo beef, M/S was increased.

• Applied Biological Chemistry
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• v.28 no.4
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• pp.226-232
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• 1985

Changes in lipid and fatty acid composition in Korean native Meju were investigated at one week interval over 6 weeks of fermentation. For the systematically, salicic acid column chromatography and gas liquid chromatography were used. Following results were obtained. 1. The lipid fraction obtained from the soared soybean and the cooked soybean were mainly composed of $72.47%{\sim}92.35%$ of neutral lipid, phospholipid and glycolipid were 4.64% and 4.88%, respectively. During fermentation period, lipid content decreased to 80.59%, but glycolipid and phospholipid contents increased. 2. The triglyceride contents of nonpolar lipids prepared from the cooked soybean and the soaked sobean was 89.66% and 87.83% respectively. Free fatty acid, diglyceride and sterol contents increased during fermentation, whereas triglyceride content decreased. 3. Lipids extracted from the soaked soybean and the cooked soybean were composed of 54.58% linoleic acid, $22{\sim}20%$ oleic acid, $10{\sim}12%$ palmitic acid and $3{\sim}5%$ stearic acid. 4. During the Korean native Meju fermentation in palmitic acid decreased from the second week and stearic acid through $3rd{\sim}4th$ week. Oleic acid and linoleic acid content decreased gradually, but linolenic acid content increased. 5. During the fermentation, myristic acid content of glycolipid fraction increased. Lipase activity reached to the maximum at the 3rd week.

• Korean journal of food and cookery science
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• v.25 no.5
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• pp.600-605
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• 2009

This study was conducted to investigate the fat content, fatty acid composition, trans fatty acid content, and acid value of twenty types of fried chickens purchased in local markets in Korea. The fat was extracted from the fried chickens and analyzed by the folch method, which revealed that the content ranged from 4.94% to 18.06%. The major fatty acids in the fried chickens were oleic acid ($29.78{\sim}67.85%$), linoleic acid ($8.42{\sim}39.54%$), and palmitic acid ($10.67{\sim}25.43%$). Twenty types of fried chickens contained less than 0.1 g of trans fatty acid per 100 g of chicken, while the fatty acid value ranged from $0.86{\sim}2.65$, which is lower than the KFDA criteria.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.75-84
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• 1987

Lipids in Bush Clover (Lespedza bicolor) seed were extracted with the mix ture of chloro-form-methanol (2 : 1, v/v) and then fractionated into neutral lipids, glycolipids and phospholipids by silicic acid column chromatography. Components and fatty acid composition of each fraction were determined by thin layer and gas chromatographies. The results were summarized as follows. In Bush Clover seed, the contents of neutral lipids, glycolipids and phospholipids were 71.75%, 23.26% and 4.99% respectively. Triglycerides(61.90%) and free fatty acids(22.04%) were the major components among the neutral lipids. Esterified sterols, free sterols, diglycerides and monoglycerides were the minor components. The major components of glycolipids were monogalactosyl diglycerides(38.19%) the others were esterified steryl glycosides, cerebrosides and digalactosyl diglycerides. The major components of the phospholipids were phosphatidyl cholines(36.46%), phosphatidyl inositols(21.52%) and phosphatidyl ethanolamines(17.29%). The major fatty acid of total lipid, neutral lipids and glycolipids were linoleic acid, linolenic acid, oleic acid and palmitic acid. On the other hand, predominate fatty acid of phospholipids were linoleic acid, palmitic acid, linolenic acid and stearic acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.162-166
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• 1991

Twenty brands of five different types of deep-fat fried foods including doughnuts, vegetables, fried chicken and french fries were purchased from food stores and fast food restaurants in Daegu city. These sample were analyzed for their total lipid content and fatty acid composition. The total lipid contents of each type of foods were over 20% by weight on an average. One brand of the doughnuts had the highest lipid content of 55.2%. The average polar lipid content of the five different types of samples was approximately 40% of the total lipid content. The fatty acid compositions of the total lipid in the deep-fat fried foods were similar to one another. HTe major fattyacids were oleic acid, stearic acid, linoleic acid in order of content. Minor fatty caids ere myristic acid, palmitic acid, palmitoleic acid, linolenic acid, behenic acid and erucic acid.