• Food Science and Preservation
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• v.7 no.1
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• pp.44-50
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• 2000

Physicochemical properties and sensory evaluation of Satsuma mandarin produced in Cheju were investigated . Fruit index(width/Length), soluble solids and acid content of Citrus unshiu marc. var. miyagawa(miyagawa) and C. unshiu marc. var.(okitsu) harvested at 1st December were 1.16 and 1.23, 12.12 and 12.01, 0.97 and 1.09, respectively. and the fruit of miyagawa was showed somewhat round in shape, compared to ikitsu. the taste of miyagawa seemed to be better than okitsu. However, compared to miyagawa, peel thickness was thinner, flesh ratio was higher, and firmness was higher as 0.502kg-force in kitsu. Nevertheless there were some differences among panelist groups in sensory evaluation , middle size of citrus fruits were favorable to most panelists, but except very small or very large size of fruits, there were not so much differences in okitsu. The panelists referred to somewhat flat-shaped fruits from that sensory evaluation score was increased to 1.3 in fruit index. nevertheless there were not so much differences in full-colored fruits, the citrus peel color of reddish yellow was more favorable than greenish or pale yellow color. the score was increased more linearly according to citrusfruit produced in optimum ciltivation area, and was prefered to thinner in peel thickness , Correlation between soluble solids, acid content , Brix/acid ratio and flesh ratio with sensory evaluation score were not showed significantly, it was different to with citrus juice. This data obtained in this experiments are supposed to be applied to the quality evaluation of Satsuma mandarin produced in Cheju .

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.108-108
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• 2007

Inkjet printing is a non-contact and direct writing associated with a computer. In the industrial field, there have been many efforts to utilize the inkjet printing as a new way of manufacturing, especially for electronic devices. The etching resist used in this process is an organic polymer which becomes solidified when exposed to ultraviolet lights and has high viscosity of 300 cPs at ambient temperature. A piezoelectric-driven ink jet printhead is used to dispense $20-40\;{\mu}m$ diameter droplets onto the copper substrate to prevent subsequent etching. In this study, factors affecting the pattern formation such as printing resolution, jetting property, adhesion strength, etching and strip mechanism, UV pinning energy have been investigated. As a result, microscale Etch resist patterning of printed circuit board with tens of ${\mu}m$ high have been fabricated.

• Journal of Korean Society of Forest Science
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• v.53 no.1
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• pp.44-55
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• 1981

Neutral sulfite precooked fir chips were refined in the Asplund Laboratory Defibrator at various temperature ($20^{\circ}C$, $120^{\circ}C$ and $180^{\circ}C$). The effects of refining temperatures on the physical property and morphological structure of the resulting pulps were discussed. Yields of precooked chips (84%, 92% and 100%) and refining temperature affected remarkably the yield of refined pulp, its beatability, sheet strength and morhphological characteristics. Pulp yield and beatability decreased with increasing refining temperature. Fiber surface of unbeaten pulp from precooked chips of 84% yield was to some extent covered by the secondary wall, while that of the pulp form precooked yield of 92% by the compound middle lamella. In the case of uncooked chips, fibers were damaged heavily, and the exposed fiber surface resulted from the equal amount of the secondary wall and the compound middle lamella. In the case of pulps prepared from precooked chips of higher yields (92% and 100%), sheet strength increased linearly as sheet density increased. But at the same sheet density, pulp from lower precooked yield (84%) had better sheet strength after open discharge refining as compared to pressurized refining, because pulp from the former had much amounts of fines fraction of higher water retention value than the latters. And there was observed a little difference in fiber length distribution but nearly similar in its morphology with increasing refining temperature.

• Journal of Powder Materials
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• v.20 no.6
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• pp.467-473
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• 2013

This research presents a preparation method of dental components by metal injection molding process (MIM process) using titanium scrap. About $20{\mu}m$ sized spherical titanium powders for MIM process were successfully prepared by a novel dehydrogenation and spheroidization method using in-situ radio frequency thermal plasma treatment. The effects of MIM process parameters on the mechanical and biological properties of dental components were investigated and the optimum condition was obtained. After sintering at $1250^{\circ}C$ for 1 hour in vacuum, the hardness and the tensile strength of MIMed titanium components were 289 Hv and 584 MPa, respectively. Prepared titanium dental components were not cytotoxic and they showed a good cell proliferation property.

• Textile Coloration and Finishing
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• v.27 no.4
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• pp.334-339
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• 2015

Polyketone fiber, a newly developed high strength fiber, has a tenacity and modulus similar to the paramid fiber, and can be used for reinforcing mechanical rubber goods(MRG), such as tires, hoses, and technical textiles. In addition, aliphatic polyketone, which has excellent strength, modulus, chemical stability and reasonable price, is being developed only in South Korea. It will be expected for replacement of super fiber such as aramids and increasing the technical textile market share. This paper surveys the mechanical properties of polyketone fiber yarn for technical textiles. For this purpose, two kinds of yarns are prepared, mechanical properties of coated and uncoated polyketone yarns such as tensile strength, elongation and modulus were examined before and after weather resistance test(temperature $60^{\circ}C$, humidity 60%, amount of power $0.67w/m^2$). The differences of mechanical properties between uncoated and coated yarns for high functional technical textiles and composite materials are estimated through this study.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.51-56
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• 1994

Development for extraction method of sea tangle was investigated with addition of sucrose, NaCl, EDTA-2Na, SHMP, and hydrolysis with commercial polysaccharide hydrolyzing enzymes. The total solids and protein yields were significantly increased by enzymatic hydrolysis or addition of NaCl and EDTA-2Na during boiling. The extract prepared by enzymatic hydrolysis followed by 2 hrs of boiling in 1.5% NaCl solution was significantly improved in solids and protein yield from 24.1% and 13.9% of 2 hrs of water boiling to 44.6% and 32.2%, respectively. The combined method increased the amino-nitrogen content but reduced the turbidity and viscosity. Extracts with a high intensity of total and seaweed-like taste as revealed by sensory evalution were obtained by combined method.

• Toxicological Research
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• v.14 no.3
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• pp.427-433
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• 1998

The acute and genetic toxicity of DK1002 was subjected in this study. DK1002 which is a morphine-like new drug candidate synthesized by Dong-Kook Pharmaceutical Co. Ltd. is now under developing as a analgesics that have better drug efficacy and least addictive property. In acute toxicity study, the 50% lethal doses ($LD_{50}$) of DK1002 were determined as>2000mg/kg (p.o.), 237.0mg/kg(i.p.), 57.5mg/kg(i.v.), and 1266.9mg/kg (s.c.). And also, to study the genotoxicity of DK1002, we performed bacterial reversion assay with Salmonella typhimurium TA98, TA100, TA1535, and TA1537, and in vitro chromosomal aberration assay with Chinese hamster lung cells in the presence and absence of S-9 metabolic activation system. In vivo micronucleus assay using mouse bone marrow cells was also performed. From these results, DK1002 was revealed nonmutagenic potential in S. typhimurium TA98, TA100, TA1535, and TA537 both in the absence and presecne of metablic activation system. No clastogenicity of DK1002 was observed in chromosomal aberration assay in vitro as well as in micronucleus assay in vivo.

• Biomolecules & Therapeutics
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• v.17 no.3
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• pp.276-281
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• 2009

Lactic acid bacteria (LAB) are considered as probiotics with immunostimulatory property. In this study, we investigated the molecular mechanism of its immunostimulating potency on macrophages using combined preparation of LAB (cpLAB). cpLAB is able to strongly stimulate nitric oxide (NO) production as well as inducible NO synthase (iNOS) expression from macrophage-like RAW264.7 cells. The cpLAB-induced NO release seemed to be mediated by extracellular signal-regulated kinase (ERK) but not p38 and C-Jun N-terminal kinase (JNK), since U0126, an ERK inhibitor, clearly suppressed NO production. cpLAB significantly diminished the binding of toll like receptor (TLR)-2 antibody up to 25%, implying that cpLAB-mediated activation of macrophages may be required for the functional activation of TLR-2, but not TLR-4. Therefore, our data suggest that cpLAB may directly allow macrophages to immunostimulating potency via activation of TLR-2 and ERK.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.1
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• pp.26-33
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• 2012

Phosphoric acid-doped poly (2,5-benzimidazole) (DABPBI) was prepared by condensation polymerization of 3,4-diaminobenzoic acid for high temperature proton electrolyte membrane fuel cells. The membranes were casted directly using a hot-press unit and characterized by fourier transform infrared spectroscopy, thermogravimetric analysis, conductivity measurement, scanning electron microscopy and tensile test. The proton conductivities of DABPBI are observed to be 0.062 and 0.018 $S{\cdot}cm^{-1}$ under 30 and 1% relative humidity, respectively at a temperature of $120^{\circ}C$ which is appreciably higher than that of Nafion 115 under similar conditions. The DABPBI membrane has demonstrated excellent thermo- mechanical properties and proton conductivity suggesting its suitability as a high temperature membrane.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.239-242
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• 1998

Ca $F_2$ films have superior gate insulator properties than conventional gate insulator such as $SiO_2$, Si $N_{x}$, $SiO_{x}$, and T $a_2$ $O_{5}$ to the side of lattice mismatch between Si substrate and interface trap charge density( $D_{it}$). Therefore, this material is enable to apply Thin Film Transistor(TFT) gate insulator. Most of gate oxide film have exhibited problems on high trap charge density, interface state in corporation with O-H bond created by mobile hydrogen and oxygen atom. This paper performed Ca $F_2$ property evaluation as MIM, MIS device fabrication. Ca $F_2$ films were deposited at the various substrate temperature using a thermal evaporation. Ca $F_2$ films was grown as polycrystalline film and showed grain size variation as a function of substrate temperature and RTA post-annealing treatment. C-V, I-V results exhibit almost low $D_{it}$(1.8$\times$10$^{11}$ $cm^{-1}$ /le $V^{-1}$ ) and higher $E_{br}$ (>0.87MV/cm) than reported that formerly. Structural analysis indicate that low $D_{it}$ and high $E_{br}$ were caused by low lattice mismatch(6%) and crystal growth direction. Ca $F_2$ as a gate insulator of TFT are presented in this paper paperaper