• Elastomers and Composites
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• v.44 no.1
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• pp.34-40
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• 2009

New coupling agent or surface modified agent (9-decenoic acid) was used to enhance the compatibility between silica and polystyrene in silica/polystyrene hybrid nanocomposite, synthesized by in situ miniemulsion polymerization. Composites contain well dispersed nanosize silica particles. Related tests and analyses confirmed the success of synthesis. Functionalization of silica by 9-decenoic acid and silica on the polystyrene was confirmed by FTIR. TGA showed presence and amount of silica in final latex. The glass transition temperature of the hybrid nanocomposite was increased with the silica amount. SEM and TEM analysis showed the spherical morphology of PS and composite with an average diameter of 55 nm. The presence of silica within composite was confirmed by EDS attached to the existing TEM.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.102-109
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• 1991

Quality of three kinds of honey from acacia, chestnut and polyflower sources, was evaluated by physicochemical and GC-MS analysis in respect to some chemical composition. The average contents of moisture, ash, HMF(hydroxy methyl furfurol) and free acidity were 19.7% , 0.028% , 18.28mg/kg and 8.85meq/kg , respectively, in acacia honey, 19.1% , 0.05% , 18.47mg/kg and 10.24 meq/kg , respectively, in polyflower honey, and 18.9% , 0.050% , 20.21mg/kg, 12.28meq/kg respectively, in chestnut honey. The average contents of glucose and fructose ranged from 31.0 to 32.0% and from 35.0 to 36.0% , respectively, in all three kinds of honey. The average ratio of fructose to glucose was 1.14 in all three kinds of honey. Fatty acid composition in honey identified by GC-MS analysis was dodecanoic acid, 10-hydroxy-2-decanoic acid, 6,9-undecadienoic acid, tetradecanoic acid, 12-(acetyl oxy) -9-octadecenoic acid and 14-octadecenoic acid. The content of 10-hydroxy-2-decenoic acid was about 10% in three kinds of honey.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.3
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• pp.270-277
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• 2017

This study was carried out to investigate seasonal changes in body composition in Boleophthalmus pectinirostris in Korea. B. pectinirostris collected in Gangjin, Jeonnam, consisted of 58.7-75.8% moisture content, 16.1-17.6% protein, 0.8-3.4% crude lipids, and 1.3-3.6% crude ash. Livers consisted of 15-17% moisture content, 14.0-16.8% crude protein, 34.4-71.2% crude lipids, and 0.5-1.2% crude ash. Calcium, iron, potassium, etc., content in B. pectinirostris muscle averaged 267.5-599.8 mg/100 g, 1.98-28.3 mg, 160.7-327.9 mg, 20.6-60.2 mg, 0.4-2.2 mg, 0.23-0.46 mg, 66.5-192.9 mg, and 1.32-3.8 mg, respectively. (Please clarify: the list of measured values must correspond directly with what was measured, not just "etc.") The major amino acids in B. pectinirostris muscle, in proportional order, were glutamic acid, isoleucine, and leucine; whereas the major amino acids in the liver were glutamic acid, lysine, aspartic acid, and leucine. The major saturated fatty acids in the muscle were palmitic acid (15-19%) and stearic acid (8-11%). The major monoenes and polyenes were palmitoleic acid (C16:1) and oleic acid (C18:1), and EPA and DHA, respectively. The major saturated fatty acids and polyenes in the liver were the same as in muscle, but the monoenes were palmitoleic acid (C16:1) and cis-10-hepta-decenoic acid (C17:1). Seasonal changes in B. pectinirostris body composition may be attributable to differential accumulation of fat and nutrients in comparison to the spawning and hibernation period.