• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.5
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• pp.325-330
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• 1992

This paper deals with the antioxidative activities of some spices on the autoxidation of refined sardine oil. The various spices powders(120mesh) were added into the refined sardine oil at the level of $0.1\%$ (w/w), and then incubated at $37^{\circ}C$ Among spices tested, herb spices showed higher antioxidative activities than spicy and seed spices. Especially, the antioxidative activities of herb spices on peroxidation of refined sardine oil were most effective in rosemary and sage. Furthermore, the available antioxidative compounds of rosemary and sage were fractionated into petroleum ether-soluble and -insolubles. Petroleum ether-soluble fractions(PESF) obtained from rosemary and sage on the autoxidation of refined sardine oil had a great antioxidative activities. The yields of PESF obtained from rosemary and sage were $10.3\%\;and\;12.6\%$, respectively. The PESF of rosemary and sage showed higher antioxidative effects than butylated hydroxytoluene(BHT), and indicated predominant metal ion-scavenging effect in PESF-refined sardine oil systems.

• Magazine of the Korea Concrete Institute
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• v.9 no.3
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• pp.149-156
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• 1997

In order to improve compressive strength of cement mortar, powder admixture(FAS) was mmufactured by mixing fly ash. Il-anhydite and silica hume, and superplasticizer was used for the control of fluidity reduction with the use of this admixture. Cement was substituted by 10, 20wt% of FAS respectively. At W/S = 0.40, the fluidity of' cement paste substituted by PAS was decreased. NSF and NT-2 were very effective fbr the control of fluidity reduction. As the particle size of U -anhydrite was fine, the fluidity of cement mortar was increased. The fluidity reduction of cement mortar substituted by 10wt% of FAS was controlled. The compressive strength of cement mortar substituted by 10wt% of FAS showed higher. value than that of 20wt%, expecially specimen(C1) substituted by 10wt% of $\gamma$ had the highest compressive strength value.

• Journal of Welding and Joining
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• v.23 no.6
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• pp.99-105
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• 2005

The mixing ratio effect of the GTD-111(base metal) powder and the GNI-3 (Ni-l4Cr-9.5Co-3.5Al-2.5B) powder on TLP(Transient Liquid Phase) bonding phenomena and mechanism was investigated. At the mixing ratio of the base metal powder under $50wt\%$, the base metal powders fully melted at the initial time and a large amount of the base metal near the bonded interlayer was dissolved by liquid inter metal. Liquid insert metal was eliminated by isothermal solidification which was controlled by the diffusion of B into the base metal. The solid phases in the bonded interlayer grew epitaxially from the base metal near the bonded interlayer inward the insert metal during the isothermal solidification. The number of grain boundaries farmed at the bonded interlayer corresponded with those of base metal. At the mixing ratio above $60wt\%$, the base metal powder melted only at the surface of the powder and the amount of the base metal dissolution was also less at the initial time. Nuclear of solids firmed not only from the base metal near the bonded interlayer but also from the remained base metal powder in the bonded interlayer. Finally, the polycrystal in the bonded interlayer was formed when the isothermal solidification finished. When the isothermal solidification was finished, the contents of the elements in the boned interlayer were approximately equal to those of the base metal. Cr-W borides and Cr-W-Ta-Ti borides formed in the base metal near the bonded interlayer. And these borides decreased with the increasing of holding time.

• Korean journal of food and cookery science
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• v.29 no.1
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• pp.19-28
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• 2013

This study was carried out to investigate the quality characteristics and storage of noodle with added flowering cherry fruit powder. Wet noodles were prepared at concentration of 1, 2, and 3% (w/w) of the fruit based on flour weight. Moisture content of the noodles with or without flowering cherry fruit powder was 33.09~33.50%. Ca, K and Mg contents of flowering cherry fruit noodle were increasing at increasing concentrations of flowering cherry fruit powder. Cooked weight, volume, and water absorption decreased with increased fruit powder, whereas turbidity increased. For Hunter's color values of noodles, L (lightness) and b (yellowness) values decreased with increasing concentration of flowering cherry fruit powder, whereas a (redness) value increased. For mechanical characteristics of the noodles, adhesiveness of cooked noodle with flowering cherry fruit powder were higher than those of control. The pH of flowering cherry fruit noodle was lower than that of control during storage. Bacterial counts of wet noodle with flowering cherry fruit powders were lower than those of the control on the 10th day of storage at $5^{\circ}C$. From the sensory evaluation of 20's, texture, taste, and overall preference were not significantly different between the control and the fruit groups, but the color scores of 2% and 3% flowering cherry fruit noodle were significantly higher than that of 1% fruit noodle (p<0.05). In 40's sensory evaluation, color and overall preference scores of flowering cherry fruit noodle were significantly higher than those of control. In conclusion, the results of this study were suggested that the addition of flowering cherry fruit powder in combination with flour was tended to improve antimicrobial effects during storage when compared to control.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.169-176
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• 2023

This study aims to develop a thermally conductive backfill by applying the prepacked concrete concept, in which a coarse aggregate with relatively high thermal conductivity was first filled and then the voild filled with grout. Backfill with improved thermal conductivity can increase the heat exchange efficiency of underground heat exchangers or underground transmission facilities. The backfills was prepared by using crushed concrete as the coarse aggregate, fly ash-based grout, and a small amount of cement for solidification. The results of this study showed that the fly ash-cement-sand-based grout with a flow of at least 450 mm accor ding to ASTM D 6103 could fill the void of pr epactked coar se aggr egates with a maximum size of 25 mm. The thermal conductivity of the backfil with coarse aggregate was over 1.7 W/m·K, which was higher than that of grout-type backfills.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.112-118
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• 2001

To study effect of non-fat components present in plant seeds on lipid metabolism, defatted safflower and perilla seed powders were used in high cholesterol diets for ovariectomized (ovx) female Sprague-Dawley rats weighing 227$\pm$15g. Experimental groups were six as follows; normal group without ovariectomy and cholesterol-free diet, sham and ovx-control groups with high cholesterol and cellulose for dietary fiber, ovx-est group with the same diet as ovx-control but with eight subcutaneous injections of 50$\mu\textrm{g}$ 17$\beta$-estradiol. ovx-safflower and ovx-perilla with 29% and 16% (w/w) of each defatted powder in high cholesterol diets at the expense of cellulose. Weight gains were lower in normal and sham groups and food efficiencies were lower in normal,ovx-est and ovx-safflower groups compared with ovx-control. Uterus weights were dramatically reduced by ovariectomy but restored completely by 17$\beta$-estradiol and partially (~5%) by defatted safflower. Plasma levels of total cholesterol were not different among ovx-control, sham, vx-est and ovx-safflower groups (90.8~95.1 mg/dL) but that was lower in ovx-perilla (80.4$\pm$6.2 mg/dL). Plasma triglyceride (TG) levels were lower in sham (76.6$\pm$7.0 mg/dL) and ovx-perilla (79.2$\pm$5.8 mg/dL) groups. Liver cholesterol levels were lower in sham, ovx-est, ovx-safflower and ovx-perilla groups (26.6~29.8 mg/g) than ovx-control (36.5$\pm$3.2 mg/g). But liver TG levels were reduced only sham and ovx-est groups compared to control group. Fecal excretions of bile acid and cholesterol were highest in ovx-safflower group (30.8$\pm$5. and 32.1$\pm$5.7 mg/g) compared with other ovx groups (20.8~23.1 and 12.1~19.5 mg/g). These results suggest that both perilla and safflower seeds contain groups (20.8~23.1 and 12.1~19.5mg/g). These results suggest that both perilla and safflower seeds contain non-fat and non-fiber components having lipid lowering effects.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.856-861
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• 2002

Surface-modified powders were produced by hybridization system using core freeze-dried lactic acid bacteria (Lactobacillus acidophilus ATCC 43121) and enteric coating materials. Scanning electron microscopy showed that the surface of freeze-dried lactic acid bacteria changed to smooth round shape during surface reforming process, although no significant physical damages affecting the activity of the lactic acid bacteria were observed based on viability and salt-tolerance tests. Signigicant difference was not found in acid tolerance test probably due to the inherent acid tolerance of L. acidophilus ATCC 43121. Significantly improved heat tolerance was obtained by surface modification process. Among the tested coating materials, Sureteric showed a higher surface- reforming ability than Eudragit S100 and L100-55. Core : coating ratio agent of 9 : 1 (w/w) with rotor speed of 15,000 rpm for 3 min were determined to be optimum conditions for the process.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.257-260
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• 2007

In this study, $CuInSe_{2}$ (CISe) and $CuInZnSe_{2}$ (CIZSe) thin films were prepared on Corning 1737 glass by radio frequency (RF) magnetron sputtering from binary chalcogenide mixed powder targets. The targets were initially prepared by mixing appropriate weights of CuSe, InSe powder and various ZnSe contents. From the film bulk analysis result, it is observed that Zn concentration in the films increases proportionally with the addition of ZnSe in the sputtering targets. Under optimized conditions, CISe and CIZSe thin films grow as a chalcopyrite structure with strong (112), (220/204) and (312/116) reflections. Films are found to exhibit a high absorption coefficient of $10^{4}$ $cm^{-1}$. An increasing of optical band gap from 1.0 eV (CISe) to 1.25 eV (CIZSe) is found to be proportional with an increasing of Zn concentration as expected. All films have a p-type semiconductor characteristic with a carrier concentration in the order of 1014 $cm^{-3}$, a mobility about $10^{1}$ $cm^{2{\cdot}-1}{\cdot}s^{-1}$ and a resistivity at the range of $10^{2}-10^{6}$ W${\cdot}$m.

• Journal of Powder Materials
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• v.21 no.2
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• pp.137-141
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• 2014

In this study, we report the sintering behavior and properties of a $Ge_2Sb_2Te_5$ alloy powders for use as a sputtering target by spark plasma sintering. The effect of various sintering parameters, such as pressure, temperature and time, on the density and hardness of the target has been investigated in detail. Structural characterization was performed by scanning electron microscopy and X-ray diffraction. Hardness and thermal properties were measured by differential scanning calorimetry and micro-vickers hardness tester. The density and hardness of the sintered $Ge_2Sb_2Te_5$ materials were 5.8976~6.3687 $g/cm^3$ and 32~75 Hv, respectively.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1405-1407
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• 2001

It was studied to prepare high temperature heating elements using molybdenum disilicide($MoSi_2$). Molybdenum disilicide is widely used as material for manufacturing high temperature heating elements. $MoSi_2$ heating elements could be used at 1700-1900$^{\circ}C$. However, it is relatively expensive, and its demand depends on import. $MoSi_2$ powders was mixed with 4-5wt% of montmorillonites type bentonite as plasticizer and a small amount of $Si_3N_4$, $ThO_2$, and B as additives to prepare specimen of heating elements. Then, it was extruded, dried, sintered and machined followed by heating test. Effects of sintering conditions and amount of additives were investigated, It was sintered effectively at 1,350$^{\circ}C$ for five hours. Electrical resistivity was decreased with increasing of sintering temperature and time, and related with apparent density of the specimens. It was linealy decreased with increasing of sintered density. The heating elements thus prepared was stable at 1700$^{\circ}C$ and the physical properties such as specific electrical resistivity, hardness, apparent density, thermal expansion coefficient, and bending strength were almost identical with those of commercial heating elements.