• Journal of Animal Environmental Science
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• v.13 no.3
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• pp.195-200
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• 2007

Management of odors is essential to swine industry in the Republic of Korea. This study was conducted to evaluate the odor removal efficiency of biofilter ducting systems. Rice straw and auto clave concrete(ALC) were used as filter medium. The ventilation fans(5 units, diameter: 500 mm) at the side wall of a growing pig housing were connected to a biofilter using a duct. The size of a biofilter is $2.5{\times}2{\times}1.2(W{\times}L{\times}H)$. The air velocities at the 300 mm above rice straw and ALC were 0.77 and 0.56 m/s, respectively. Ammonia concentration at the outlet of rice straw and ALC media were 2 and 3 ppm, respectively. Dust concentrations were also measured. The dust concentrations of rice straw and ALC were 93, $32\;mg/m^3$, respectively. There was no significant difference between filter mediums in terms of carbon dioxide concentrations(rice straw: 320, ALC: 270 mg/l). The concentration of hydrogen sulfide was stable over the experimentation. The actual concentrations of hydrogen sulfide were 4, 3 and 3 ppm at the days of 7, 21 and 36, respectively. These results suggest that biofilter ducting systems may remove odors from pig house effectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.2
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• pp.89-97
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• 1983

This experiment was carried out in order to study the effect of seasonal changes and location differences on the productivity of the native reed (Phragmites Communis Trinius). The samples of reed were taken at about 30-days interval from May to October, 1982, on the open field of the reclaimed land, the river bank and the tideland in Chonnam area, and measured the yield, the feed compositions and in vitro dry-matter digestibility(IVD). The results are summarized as follow: 1. Plant height was rapidly heightened in May and June, and the number of leaves rapidly increased from May to August. However, dry matter yield increased until September and gradually decreased thereafter. 2. In general, the content of crude protein and the in vitro dry matter digestibility decreased with ageing, and the content of fiber increased. 3. Considerable difference by location in the chemical composition including $SiO_2$, Ca and P was observed. 4. There was a significant negative correlation (p<0.05) between the content of crude protein and that of crude fiber. There was a significant positive correlation(p<0.05) between the in vitro dry-matter digestibility(IVD) by two-stage method and the content of crude protein, and also was a significant negative correlation(p<0.05) between the content of fiber and that of crude protein.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.536-539
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• 2002

This study was investigated for the preparation method of meju by three step fermentation. The steamed soybeans were fermented with nisin-producing Lactococcus lactis subsp. lactis IFO12007 to inhibit the growth of odor-producing Bacilli and promote of normal fermentation of meju. The lactie-fermented soybeans were further fermented with Aspergillus oryzae and Bacillus subtilis. The produced meju by this method showed 54%moisture content and pH 7.0, respectively. The three step fermented meju was soaked in 20% (w/v) brine at $25^{\circ}C$ for 90days. After 30 days, the contents of total free amino acids revealed 4,015 mg% which were higher $3{\sim}5$ times than controls. Among the detected free amino acids, the contents of glutamic acid and leucine showed 925 mg% and 380mg%, respectively. Therefore, the new method of producing meju would be an excellent alternative to improve the quality of soybean fermented food, such as doenjang and kanjang.

• Journal of Nutrition and Health
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• v.28 no.1
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• pp.33-45
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• 1995

Serum levels of antioxidant vitamins and lipids were determined along with anthropometric measurements in 174 healthy male subjects with mean age of 50.3$\pm$6.8 years from Taegu area in Korea. Body mass index (BMI) and waist/hip(W/H) ratio of the subjects were 23.18$\pm$2.46 and 0.88$\pm$0.04, respectively and their systolic and distolic blood pressures were 127.8$\pm$15.5 and 83.9$\pm$10.8mmHg. Twenty one percent of the subject had BMI over 25. Average seum levels of total cholesterol, LDL- and HDL-cholesterol and triglyceride were 187.7$\pm$34.9, 117.6$\pm$33.5, 41.1$\pm$9.0 and 140.7$\pm$83.6mg/dl, respectively. Sixteen percent of the subject had LDL-chole-sterol over 130mg/dl. Serum level of lipid peroxide measured as thiobarbituric acid reactive substances(TBARS) of the subject was 2.01$\pm$0.77 MDA nmoles/ml and those of $\alpha$-tocopherol, retinol. ascorbic acid and sum of $\alpha$- and $\beta$-carotene were 9.59$\pm$3.11$\mu\textrm{g}$/ml, 1.15$\pm$ 0.38$\mu\textrm{g}$/ml, 10.5$\pm$3.8$\mu\textrm{g}$/ml and 64.6$\pm$43.$\mu\textrm{g}$/dl, respectively. About 14% of the sujects had low vitamin E status of less than 7.0$\mu\textrm{g}$/ml,. while 6% had low vitamin C status of less than 4.0$\mu\textrm{g}$/ml, Serum vitamin E showed positive correlations with total cholesterol and LDL-cholesterol and triglyceride, but no correlation with TBARS. Fatty acids of serum total lipid were composed of 42.9% as saturnted. 19.3% as monounsaturated and 36.7% polyunsaturated fatty acids(PUFA). N-6 and n-3 PUFA were 27.7% and 8.3% of total fatty acids. N-6/n-3 PUFA ratios were negatively correlated both with serum total cholesterol and TBARS.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.607-611
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• 1999

Carrageenan are sulfated polymers containing galactose and anhydrogalctose units, and is used for its gelling, thickening, stabilizing, emulsifying, and suspending properties. However, carrageenan is limited to use beyond $0.03\%$ as food additives because of its high degree of gelling and viscosity with low solubility. The use of ultrasound significantly reduced the viscosity of $\lambda$-carrageenan solutions. The optimal parameters of ultrasound for reduction of carrageenan molecular weight were temperature, $10^{\circ}C$ ultrasound intensity, 114.7 $W/cm^2$ ; carrageenan concentration, $2\%$; treatment time, 10 min. The molecular weights of control, ultrasound peak 1, and peak 2 were approximately 250,000, 184,000, and 67,000 daltons, respectively. The lower molecular weight of $\lambda$-carrageenan showed the higher solubility, the lower alcohol precipitation ratio and the lower emulsifying capacity. Browning degree of both control and lower molecular $\lambda$-carrageenans was not significantly different.

• Journal of the Korean Institute of Gas
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• v.2 no.1
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• pp.7-13
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• 1998

In this study, for the safety performance of LNG storage tank, the fracture toughness in X-grooved weld HAZ(heat-affected zone) of $9\%$ Ni steel was evaluated qualitatively and quantitatively, and the relation with the change in microstructure was analyzed. The toughness assessment was peformed through the modified CTOD test proposed for thick weldment with X-groove. Additionally, microstructures of HAZ were evaluated by OM, SEM and XRD. From the results, HAZ toughness of SMA(shielded metal arc)-welded $9\%$ Ni steel decreased as the evaluated region approached the fusion line. The decrease in toughness was apparently caused by the increase in the fraction of coarse-grained zone within HAZ. On the other hand, toughness drop with decreasing test temperature in F.L.(fusion line) ${\~}$F.L.+3mm was larger than that in F.L.+5mm${\~}$F.L.+7mm region due to the fact that in the former regions, retained austenite had poor stability.

• Journal of the Korean Institute of Gas
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• v.2 no.4
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• pp.18-24
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• 1998

Polyurethane (PU) synthesized from 4,4'-diphenylmethane diisocyanate having high functionality (f=2.9) and polyester polyol have been investigated by differential scanning calorimeter (DSC), dynamic mechanical thermal analyzer (DMTA), and Fourier transform infrared spectroscope (FT-IR). From the DSC measurement of polyurethane, a single transition temperature ($T_g$) was observed. This result indicates that polyurethanes synthesized in this work have homogeneous network structure due to high functionality of diisocyanate. It was also found that the $T_g$ of polyurethane was increased as hard segment content was increased. The results from DMTA measurement are consistent with DSC results. In order to investigate the effect of thermal annealing on the $T_g$ of polyurethane, the samples were annealed at various annealing conditions. $T_gs$ of polyurethanes were found to increased with annealing temperature. From swelling experiment and FT-IR studies, it was found that the $T_g$ was increased as crosslinking density of polyurethane was increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.461-466
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• 1991

For the purpose of improving storability and process adaptability of potato, we carried out an experiment to investigate the effects of microwave heating on the total lipid content and fatty acid composition of the potatoes in storage. The samples were made by powdering potatoes exposed to the microwave energy in a 560W, 2,450MHz oven for 0, 60, 120 and 180 seconds respectively. From the examination of the samples stored at th temperature of $25{\pm}1^{\circ}C$ for 12 months, the following results were obtained. As an over-all tendency, the longer the samples were heated and the longer they were stored, the total lipid content decreased but the microwave-heated samples showed decreasing rates less than those of the controls for the whole storage periods. As major fatty acids of the potato flour, linoleic acid (30.92 %), palmitic acid (29.34 %), linolenic acid (8.90 %) and stearic acid (8.23 %) were detected from the samples. The longer the samples were exposed with microwave, unsaturated fatty acids like 18:2, 18:3 increased. generally with the lapse of storage time, saturated fatty acids increased while unsaturated ones decreased. But in the samples heated with microwave, we observed an apparent suppression of the increasing rate of the saturated fatty acids and the decreasing rate of the unsaturated fatty acids, and the suppressing effects turned out to be proportional to the length of microwave heating.

• The Korean Journal of Malacology
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• v.29 no.3
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• pp.171-179
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• 2013

Arginine kinase (ArK) is known to play an important role in most invertebrates the level of ATP by phosphorylation of phosphagens in cell and immuninty in living organisms. ArK has been identified in many kinds of organisms ranging from invertebrate to vertebrate. However, no ArK gene has been cloned and investigated from N. samarangae. This leads us to identify ArK cDNA (NsArK) from the expressed sequence tag (EST) sequencing of N. samarangae. Sequence analysis indicated that the coding region of 1,065 bp contains 355 amino acid residues. Molecular phylogenetic analysis shows that NsArK had very high similarities with mollusca and arthropoda. In an attempt to investigate a potential role of NsArK in the digestive gland of N. samarangae, expression patterns were analyzed. RT-PCR analsysis shows that NsArK mRNA is induced in the rane of 1.2 fold at 6 hr by laminarin when compared with the control. The immunnologial and physiological role of NsArK remains to be further investigated in N. samarangae.

• Elastomers and Composites
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• v.40 no.2
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• pp.93-103
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• 2005

In this study, surface treatment of the elastomeric matrix was investigated to develop a substituting material for steel dynamic damper of automobile. The key technology is to get ultra high density elastomeric compound in order to substitute steel dynamic damper. The optimum matrix material(chloroprene rubber) and filler(metal powder) were selected for this. The several properties of elastomeric compound were examined. According to the results, the $t_{s2}$ of filled elastomeric compound was decreased with increasing the filler loading whereas the $t_{90}$ was increased. Also, tensile strength and rebound resilience were decreased with filler loading. To solve the problem of high filler loading, the photo grafting technique was employed on elastomeric matrix. The degree of grafting was determined by FTIR-ATR. Also, the filler surface was modified by chemical etching and the surface morphology was examine by SEM. After chemical treatment of filler, the particle size analyzer was used to examined the particle size, size distribution, and morphology of the modified filler.