• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.642-652
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• 2014

The synthesis of octenyl succinyl ${\beta}$-gucan (OSA-${\beta}$-glucan) was carried out and its interfacial properties at the oil-water interface and in emulsion systems were investigated. An aqueous ethanol system as a reaction media was used to facilitate the synthesis process; 10% (w/w) ethanol found to be the best as it showed a maximum degree of substitution (DS: 0.0132). FT-IR showed a characteristic absorption spectrum at $1736cm^{-1}$, indicating the esterification of octenyl succinyl groups to ${\beta}$-glucan backbone. As for interfacial tension measurements, it was decreased with increasing concentration of OSA-${\beta}$-glucan in the aqueous phase and when NaCl was added to aqueous OSA-${\beta}$-glucan solution in the range of 0.01 M to 0.1 M and also when pH was raised (pH 3 ~ pH 9). In systems of emulsion stabilized with OSA-${\beta}$-glucan, fat globule size found to decrease with increasing concentration of OSA-${\beta}$-glucan, showing a critical value of about $0.32{\mu}m$ at 0.5 wt%. When the OSA-${\beta}$-glucan emulsions were stored, it was found that fat globule size was increased with storage time and particularly pronounced increase was observed in emulsion with 1% OSA-${\beta}$-glucan, possibly due to depletion flocculation. Results of creaming stability evaluated by light scattering technique showed that it was more stable in emulsions containing smaller fat globule size. Surface load of OSA-${\beta}$-glucan in emulsions increased with increasing concentration of OSA-${\beta}$-glucan, suggesting a multilayer adsorption.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.3
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• pp.261-268
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• 2006

Fish-frames are processing byproducts, which are left after obtaining fillets or muscle during fish processing. The fish-frame generally consists of muscle, collagen, calcium, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). We used fish-frame powder (FFP) of chum salmon and skipjack tuna to prepare and characterize snacks for human consumption with different proportions of FFP. The crude protein and lipid contents of fish-frames were 16.3 and 9.4% for chum salmon and 18.6 and 8.3% for skipjack tuna, respectively. The volatile basic nitrogen (30.6 mg/100 g) and browning index (0.393) of FFP from chum salmon were lower than those of FFP from skipjack tuna. Thus, the FFP of chum salmon was better for making snacks than that of skipjack tuna. Five snacks were prepared with 0, 10, 20, 30, and 40% (w/w) substitution ratios of FFP from chum salmon. The moisture content of the snacks decreased (33.6 to 11.5%) with increasing FFP substitution ratio, whereas crude ash (2.9 to 7.5%), protein (11.4 to 18.4%) and lipid (13.7 to 35.1%) increased. Sensory scores for the texture and taste of the snack with 30% FFP were significantly higher (p<0.05) than those for other snacks; the color and flavor scores of all snacks did not differ significantly. The major fatty acids in the snacks were 16:0 and 18:0 as saturates, 18:1n-9 as monoenes, and 18:2n-6 and 18:3n-3 as polyenes. Snacks with FFP contained small amounts of EPA (0.5 to 0.8%) and DHA (1.3 to 1.8%) in the total lipid composition. The total amino acid content (16.08 g/100 g) of the snack with 30% FFP was higher than that of the snack without FFP (11.18 g/100 g), and the major amino acids were aspartic acid, glutamic acid, glycine, leucine, and lysine. The calcium and phosphorus contents of the snack with 30% FFP were 1,272 mg/100 g and 854 mg/100 g, respectively, and their ratio was the optimal range (2:1 to 1:2) for body absorption efficiency.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.250-250
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• 2012

Recently, multiferroic materials have attracted much attention due to their fascinating fundamental physical properties and potential technological applications in magnetic/ferroelectric data storage systems, quantum electromagnets, spintronics, and sensor devices. Among single-phase multiferroic materials, $BiFeO_3$, in particular, has received considerable attention because of its very interesting magnetoelectric properties for application to spintronics. Enhanced ferromagnetism was found by Fe-site ion substitution with magnetic ions. In this study, $BiFe_{1-x}Ni_xO_3$ (x=0 and 0.05) bulk ceramic compounds were prepared by solid-state reaction and rapid sintering. High-purity $Bi_2O_3$, $Fe_3O_4$ and NiO powders were mixed with the stoichiometric proportions, and calcined at $450^{\circ}C$ for 24 h to produce $BiFe_{1-x}Ni_xO_3$. Then, the samples were directly put into the oven, which was heated up to $800^{\circ}C$ and sintered in air for 20 min. The crystalline structure of samples was investigated at room temperature by using a Rigaku Miniflex powder diffractometer. The Raman measurements were carried out with a Raman spectrometer with 514.5-nm-excitation Ar+-laser source under air ambient condition on a focused area of $1-{\mu}m$ diameter. The field-dependent magnetization and the temperature-dependent magnetization measurements were performed with a vibrating-sample magnetometer. The x-ray diffraction study demonstrates the compressive stress due to Ni substitution at the Fe site. $BiFe_{0.95}Ni_{0.05}O_3$ exhibits the rhombohedral perovskite structure R3c, similar to $BiFeO_3$. The lattice constant of $BiFe_{0.95}Ni_{0.05}O_3$ is smaller than of $BiFeO_3$ because of the smaller ionic radius of Ni3+ than that of Fe3+. The field-dependent magnetization of $BiFe_{0.95}Ni_{0.05}O_3$ exhibits a clear hysteresis loop at 300 K. The magnetic properties of $BiFe_{0.95}Ni_{0.05}O_3$ were improved at room temperature because of the existence of structurally compressive stress.

• Journal of Life Science
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• v.24 no.2
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• pp.181-185
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• 2014

We identified SNPs (single nucleotide polymorphisms) for endothelial nitric oxide synthase (eNOS) genes in the Korean genome. eNOS is present in the vascular endothelium, platelets, and several other cell types that continuously produce modest amounts of NO. Endothelium-derived NO plays a key role in the regulation of vascular tone, and the impaired effects of NO on the cardiovascular system appear to be responsible for coronary atherosclerosis and thrombosis. In recent studies, a missense variant within exon 7 of the eNOS gene in patients with coronary spastic angina-GAG to GAT substitution, which results in the replacement of glutamic acid by aspartic acid (Glu298Asp [G894T])-has been identified and is known to be significantly associated with coronary spasm. We prepared PCR primers based on sequences in Genbank. Primers were prepared for normal and SNPs separately, as reported for other Asian countries, such as G894T. Their sequences were different only at the 3' ends so that primer extension could only by possible when base pairs between templates and primers matched. We also employed ARMS (Amplification Refractory Mutation System) technology to improve the specificity of the PCR reaction. In conclusion, we were able to demonstrate the eNOS G894A polymorphism in Korean gemone. This study should facilitate research on the cause of myocardial infarction and development on further therapy at the genetic level.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.302-309
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• 2013

The highly porous cellulosic aerogels were prepared by freeze-drying method using sodium hydroxide-urea aqueous solution in the process of dissolution, gelation, regeneration and organic solvent substitution. The structural characteristics of porous aerogel were analyzed using scanning electron microscopy and nitrogen adsorption apparatus. As a result, the dissolving pulp was completely dissolved, but filter papers and holocellulose were divided into two layers (dissolved and undissolved parts) in the process of centrifugation. The structure of aerogel from dissolved pulp showed porous pores in the surface and net-shaped network in the inner part. Aerogels from filter paper and holocellulose had the condensed porous network surface and the open-pore nano-fibril network inner structure. Undissolved form of fibers was observed in the aqueous solution of aerogel from holocellulose. The BET value ($S_{BET}$) of aerogel from dissolved pulp was ranged in 260~326 $m^2/g$, and it was decreased with the increase of concentration. Whereas, the $S_{BET}$ value of aerogel from filter paper (198~418 $m^2/g$) was increased with the increase of concentration. The $S_{BET}$ value of aerogel from holocellulose were 137 $m^2/g$ at 2% (w/w) of cellulose, and it was increased to maximum 401 $m^2/g$ at 4% (w/w) of cellulose. Then, it was decreased at 5% (w/w) of cellulose.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.1
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• pp.1-5
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• 2003

The multi-layered OELDs(organic electroluminescent devices) were prepared on the patterened ITO (indium tin oxide)/glass substrates by the vacuum thermal evaporation method. The $Alq_3$ (tris-(8-hydroxyquinoline)aluminum) low molecule compound was used as the light emission layer. TPD(triphenyl-diamine) and $\alpha-NPD$ were used as the hole transport layer. CuPc (Copper phthalocyanine) was also used as the hole injection layers. In addition, QD2 (quinacridone2) organic material with $10\AA$ thickness was deposited in the $Alq_3$ emission layer to improve the luminance efficiency. The threshold voltage was about 7V for all devices. The luminance and efficiency of devices was improved by substitution the $\alpha-NPD$ for TPD as the hole as the hole transport layer. The luminance efficiency of the OELD sample with QD2 thin film in the $Alq_3$ emission layer was found to be 1.55 lm/W, which is about 8 times larger value compared to the sample without QD2 thin layer.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.8
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• pp.1061-1068
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• 2012

These days, world wide interest about global warming and environmental pollution and exhausting fossil fuel which have been main energy source in all around the world. So many country have tried to find out the solution by investing new & renewable and clean energy. Therefore LNG have been widely used as a substitution of fossil fuel and clean energy that emits less pollutant like SOx, NOx. Therefore LNG consumption has been quickly raised and LNG carriers have been getting larger for decades. In this study, high power fiber laser was used for welding of stainless steel for LNG carrier to increase its productivity. Used material was STS316L which has low carbon less than 0.03% and its thickness was 8 mm. We carried out bead, lap and butt welding by using the fiber laser which has maximum power up to 5kW. As a result, we could find out that lap and butt joint was possible at welding speed of 2.0m/min and 3.0m/min respectively.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.584-587
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• 2007

The effect of molar substitution (MS, 0.030-0.118) on the dynamic rheological properties of hydroxypropylated rice starch pastes (5%, w/w) was investigated by small-deformation oscillatory measurements during aging. The magnitudes of storage (G#) and loss (G") moduli measured at $4^{\circ}C$ before aging increased with an increase in MS in the range of 0.030-0.118, while those of tan ${\delta}$ (the ratio of G"/G#) decreased. The G# values of hydroxypropylated rice starches, as a function of aging time (10 hr) at $4^{\circ}C$, increased rapidly at the initial stage, and then reached a plateau region at shorter aging times. However, for the native starch, the plateau values were not observed for G# after a long aging time. Increasing the MS resulted in a decrease in plateau values. The rate constant (K) for structure development during aging was described by first-order kinetics. The K values of hydroxypropylated rice starches at 0.086 and 0.118 MS were much lower than the K value at 0.030 MS.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.66-70
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• 2009

The effect of baking on the consumer perception and sensory characteristics was investigated using a model system of cookies incorporated with strawberry powder as a value-added food ingredient. Strawberry powder was incorporated into cookie dough at 4 levels (0%, 2%, 4%, and 6%, w/w) by replacing equivalent amount of wheat flour of the cookie dough. After aging and sheeting, cookies were baked at $170^{\circ}C$ for 15 min in an oven. The baked cookies were cooled to room temperature for 1 h and packed in airtight bags prior to all measurements. In terms of color, control received the most favorable mean score, which is significantly higher than others (p<0.05) followed by the 4% sample. The consumer preference on taste and aftertaste was not significantly affected by the amount of strawberry powder incorporated in the formulation (p>0.05). Samples with 4% strawberry powder received the highest mean flavor score of 6.28 which is significantly higher than that of 6% sample (p<0.05). In overall, substitution of 4% strawberry powder in the formulation would result in the most favorable strawberry cookies by the consumers with taking advantages of health benefits of strawberry. Correlation analysis indicated that strawberry powder concentration was significantly correlated positively with sensory color and hardness and negatively correlated with consumers' overall acceptability (p<0.05). Consumers' aftertaste was significantly correlated with overall acceptability which was negatively correlated with sensory hardness (p<0.05). Sensory hardness was highly correlated with sensory color attribute (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.632-637
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• 2006

Oviduct-specific glycoprotein 1 (OVGP1) is implicated in playing a role in fertilization and early embryo development. In this study, we have obtained the sequence of intron 9 of OVGP1 gene in swine. Comparative sequencing of Meishan (a native Chinese breed) and Large White pig breeds revealed an A/T substitution at position 943. A PCR-EcoRI-RFLP assay was developed to detect this mutation. Polymorphism analysis in Qingping animals showed that pigs with BB genotype had lower number of piglets born alive (NBA) in multiple parities than pigs with AA (p<0.05) and AB genotype (p<0.01). In Large $White{\times}Meishan$ ($LW{\times}M$) $F_2$ offspring, the weight of both ovaries (OW) of the BB genotype was significantly lighter than that of AB (p = 0.05) and AA (p<0.01) genotypes. Analysis of the data also revealed that the mutation locus affected these two traits mostly by additive effects. These studies indicated that the polymorphism was associated with NBA and OW in two distinct populations and further investigations in more purebreds or crossbreds are needed to confirm these results.