• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.423-435
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• 1986

As the first part of the studies on utilization of polyunsaturated lipids in red muscled fishes like sardine (Sardinops melanosticta) and mackerel (Scomber japonicus), lipid distribution in body sections, whole body, meat, viscera, skin, and head, lipids, polar and nonpolar, and fatty acid composition of the oils obtained from these body sections, and seasonal variations in fatty acid composition, particularly in the content of polyenoic acids, EPA and DHA, were determined, The content of total lipids was ranged $22.2\%\;to\;27.2\%$ in case of sardine without broad difference between body sections, while in case of mackerel $36.7\%\;to\;38.8\%$ unevenly in skin and head. The lipids of both fish were composed of more than $80\%$ of non-polar lipid and there was not much differences in the fatty acid composition between the lipids, polar and non-polar. The major fatty acids of the lipids were $C_{14:0},\;C_{16:0},\;C_{18:0},\;C_{16:1},\;C_{18:1},\;C_{20:1},\;C_{20:4},\;C_{20:5},\;and\;C_{22:6}$, and these acids, $C_{18:1},\;C_{16:0},\;C_{22:6},\;C_{18:0},\;C_{20:5},\;C_{14:0},\;C_{16:1}$, were in high quantity in order. Seasonal variation in fatty acid composition of sardine oil did not show any great variety between sections. There was a tendency in general that saturated and monoenoic acids began to decrease in winter and showed the minimum in April; hereafter get to increase again, while polyenoic acids showed the maximum in April. Both $C_{20:5}\;and\;C_{22:6}$ acids were high in the season of April to July. Variation in fatty acid content was in a width of $8\%$ for saturated, $5\%$ for monoenoic, and $12\%$ for polyenoic acid. $C_{20:5}\;and\;C_{22:6}$ acid were varied in $9.4\%\;and\;9.8\%$, respectively. In case of mackerel oil, seasonal variation tended same as in sardine oil except the fact that the saturated and monoenoic acid decreased to the minimum in the term of April to July in which the polyenoic acid content was also higher marking $27.3\%\;to\;36.1\%$ in average. Fatty acid variation was in a range of $6.3\%$ for saturated, $8.3\%$ for monoenoic, and $13.8\%$ for polyenoic acid but variation of $C_{20:5}\;and\;C_{22:6}$ acid was 4, $3\%$ and 3, $4\%$ respectively. When fresh sardine was stored for 10 days at $5^{\circ}C$, oxidation was rapidly initialed and consequently resulted in fast loss of $C_{20:5}\;and\;C_{22:6}$ acids. It is concluded from the results that the catch of sardine and mackerel in the season of April to June would be adequate for the preparation of polyunsaturated lipid condenced oil in regard to sectional lipid distribution and its variation in seasons.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.995-1002
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• 2000

To evaluate energy efficiency and partition of nutrients, 32 piglets were weaned at 14 d of age and individually fed diets containing 15% fat from coconut oil (CO, medium chain saturated), high oleate sunflower oil (HOSO, n-9 series), soybean oil (SO, n-6 series), or linseed oil plus fish oil, (LF, n-3 series). After 4 weeks, the subjects were sacrificed to evaluate empty body composition and apparent ileal digestibility with the slaughter method. No statistical effect of dietary fat sources on growth was observed. The digestibility of fat from the coconut oil diet was higher than fats from the diets containing high levels of unsaturated fatty acids. The efficiency of use of metabolizable energy for growth averaged 63% and was not affected by the diet. Dietary fat composition was reflected strongly in backfat. Total body neutral and polar fatty acids were influenced too. For the whole body phospholipid fraction the ratio of n-6 to n-3 and the double bond index were 4.3, 5.8, 7.2, 0.78 and 69, 87, 89, 87 for CO, HOSO, SO, and LF respectively. These results show that for the coconut oil diet the degree of unsaturation of phospholipids in the body was lower and that, in the other diets, it did not differ, but double bond index was maintained with different n-6 to n-3 ratios in carcass fat. On the whole the data on body fat composition indicate that the dietary fat tended to be deposited in similar quantity in the body, whatever was the dietary fatty acid profile.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.308-313
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• 1999

Total polar lipid produced from the soybean oil and lard by heating with different surface area at $185^{\circ}C$ were measured by silica gel column chromatography. Further, the polar lipid was fractionated by high performance size exclusion chromatography-evaporative light scattering detector (HPSEC-ELSD). The HPSEC system was composed of two GPC columns $(100\;{\AA}\;and\;500\;{\AA})$ and a THF mobile phase. With this system it was possible to fractionate into the free fatty acid, diglyceride, triglyceride monomer, triglyceride dimer and triglyceride polymers. The triglyceride monomer, triglyceride dimer and triglyceride polymers significantly increased as the heating time and surface area increased. But diglyceride and free fatty acid did not increased as the heating time and surface area increased. Triglyceride polymer (r>0.93), triglyceride dimer (r>0.97), triglyceride monomer (r>0.95) showed a high correlation with polar lipid content. On the other hand, diglyceride (r<0.68) and free fatty acid (r<0.76) were not significantly correlated with the polar lipid content. These results indicated that a major oxidative components formed during thermal oxidation were triglyceride polymers and triglyceride dimer and triglyceride monomer.

• Analytical Science and Technology
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• v.25 no.4
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• pp.207-213
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• 2012

Analysis of the aroma constituents present in the rose essential oil of Chinese Kushui type (Rosa sertata ${\times}$ Rosa rugosa) by GC-FID and GC-MS was performed independently as an expert for the inter-laboratory round-robin test to verify reproducibility according to the decision of the preliminary meeting of ISO/TC-54 (Shanghai, Sep. 14-15, 2010). Total 179 peaks (using SPB-1 apolar column), 165 peaks (using DB-624 intermediate polar column), and 162 peaks (using Supelcowax-10 polar column) were separated by GC-FID, respectively. Major constituents (over 5%) by GC-FID were ${\beta}$-citronellol (41.6~46.7%), geraniol (9.7~11.0%), and nerol (3.4~4.5%). ${\beta}$-Citronellol peak was overlapped with nerol peak on SPB-1 and DB-624 columns, whereas the two peaks were separated each other on Supelcowax-10 column. Our results were generally consistent with Chinese data (ISO/DIS 25175); however, a peak of phenethyl alcohol separated by using PEG (Supelco wax) column was found at the quite different retention time. Comparative analysis was conducted using Bulgarian rose (Rosa damascena Miller) oil and perfume. Bulgarian rose oil showed rich amounts of characteristic aroma constituents than the essential oil of Chinese Kushui type.

• The Journal of the Acoustical Society of Korea
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• v.43 no.1
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• pp.49-59
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• 2024

Recently, the electric vehicle market is gradually growing due to strengthened environmental regulations and high oil prices. also, in internal combustion engine vehicles, the sensitivity of Buzz, Squeak, Rattle (BSR) noise is increasing as engine Noise, Vibration, and Harshness (NVH)-related noise is reduced and technology for shielding noise coming from outside is developed. In this study, the stick-slip noise that occurs in Panoramic Curved Display (PCD) of automobile was analyzed for the correlation between the surface energy of polymer plastic and the polar component. For polar polymer materials, Acrylonitrile Butadiene Styrene (ABS) and PolyCarbonate-Acrylonitrile Butadiene Styrene (PC-ABS), compound materials were fabricated and evaluated. As a result, when the polar component of the polymer plastic was 3.86 mN/m or higher, stick-slip motion occurred, and as the absolute transition slope increased in the friction behavior over time, the possibility of stick-slip noise increased and the value of the friction coefficient The greater the difference, the greater the strength of the stick-slip noise.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1033-1037
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• 2001

Garlic oleoresins were made by extracting with four solvents of methanol, methyl acetate hexane and acetone from chopped garlic, respectively, and the volatile compounds of each extract were separated by gas chromatography installed with polar (supelcowax-10$^{TM}$) and nonpolar (HP-5) capillary columns, respectively, and identified by matching mass data of mass selective detector and Kovat\`s retention index with references. The numbers of the volatile compounds identified the garlic oleoresin by polar and nonpolar columns from in garlic oleoresins were 41 and 32, respectively. In polar column, 13 pyrans, 11 sulfur-containing compounds 6 furans 2 alcohols and 2 heterocyclic compounds were identified. In nonpolar column, 11 sulfur-containing compounds 5 acids 3 furans and eugenol were identified. The major sulfur-containing compounds identified from the oleoresins were 3, 3'-thiobis-1-propene, methyl 2-propenyl disulfide, dimethyl trisulfide, di-2-prnpenyl-trisulfide, 2-thiophenecarboxylic acid. The amount of these sulfur-containing compounds isolated from the oleresins were more abundant in polar column than in nonpolar column. The most efficient solvent for extracting volatile compounds of garlic was methanol but the most useful solvent for extracting sulfur-containing compounds was methyl acetate of less polarity.y.

• KSTLE International Journal
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• v.4 no.1
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• pp.14-17
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• 2003

The electrical and rheological properties of a chitosan malonate suspension in silicone oil was investigated by varying the electric fields, volume fractions of particles, and shear rates, respectively, The chitosan malonate susepnsion showed a typical electrorheological (ER) response caused by the polarizability of an amide polar group and shear yield stress due to the formation of multiple chains upon application of an electric field. The shear stress fur the suspension exhibited a linear dependence on the volume fraction and an electric field power of 1.88. On the basis of the experimental results, the newly synthesized chitosan malonate suspension was found to be an anhydrous ER fluid.

• Tribology and Lubricants
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• v.25 no.3
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• pp.176-181
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• 2009

Aminated polyacrylonitrile as the new organic disperse phases of the anhydrous ER fluid has been synthesized and ER effect of the suspension composed of aminated polyacrylonitrile in silicone oil investigated. The suspension showed a typical ER response (Bingham flow behavior) upon application of an electric field. The shear stress for the suspension exhibited the dependence with a factor equals to 1.6 power on theelectric field. The current density and the conductivity of the of aminated polyacrylonitrile suspension increase with the electric field intensity and moreover the conductivity of the suspension is about 8 order of magnitude higher than that of the silicone oil. On the basis of the the results, aminated polyacrylonitrile suspension showed the ER flow behavior upon application of the electric field due to the polarizability of the branched amine polar group of the aminated polyacrylonitrile particles.

• Nutritional Sciences
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• v.3 no.1
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• pp.18-24
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• 2000

Peroxidative stimuli mediated by high polyunsaturated fatty acid administration in rats induced in vivo lipid peroxidation and resulted in increased urinary excretion of a number of lipophilic aldehydes and related carbonyl compounds. These secondary lipid peroxiation products, measured as 2, 4-dinitrophenylhydrazine deritives, were detected and identified by the newly developed HPLC method. The identified urinary lipophilic nonpolar aldehydes and related carbonyl compounds were butanal, butan-2-one, pentan-2-one, hexanal, hex-2-enal, hepta-2, 4-dienal, hept-2-enal, octanal, and oct-2-enal. Lipophilic polar aldehydes such as 4-hydroxyhex-2-enal and 4-hydroxyoct-2-enal were also identified. A polyunsaturated fatty acid diet containing n-3 fatty acids generally caused high levels of urinary excretion of lipophilic aldehydes and related carbonyl compounds in rats than a normal diet. Significantly increased secondary lipid peroxidation products were hexanal, hepta-2, 4-dienal, octanal, 4-hydroxyhex-2-exal, 4-hydroxyoct-2-enal, and a number of unidentified compunds.

• Ocean and Polar Research
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• v.28 no.2
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• pp.175-186
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• 2006

There are disputes for oil and gas development between China and Japan in the East China Sea. These involve the area where China is already carrying out activities of oil and gas development and where Japan is proclaiming its EEZ. China insists that the Chinese activities on oil and gas development area are being carried out within the Chinese jurisdictional waters even if the median line principle of Japanese proclamation is applied in delimitation. Indeed, the permit for Japanese development is causing disputes between China and Japan because its permit allows development in the waters adjacent to Chinese development area. h the event, the core of this dispute around the oil and gas field in the East China Sea relates to issues of maritime boundary delimitation and issues of resources acquisition with both states. Chinese policy on oil and gas development is to first consider development issues in accordance with a median line principle where waters toward to China from the median line should be developed by China and the area toward Japan from the median line within the Chinese continental shelf should be jointly developed. However, the Japanese position is that the East China Sea should be jointly developed, and Japan hopes to eventually convince China to accept its median line delimitation. With on-going development of such issues, Korea should establish a strategy of negotiation based on analyses of resource distributional conditions and other strategic factors in the Korean delimitation area. In particular, Korea should prepare and make the best use of joint development zone established in an agreement between the ROK and Japan concerning the development of the southern part of continental shelf adjacent to both states.