• Journal of the Korean Ceramic Society
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• v.26 no.2
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• pp.221-227
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• 1989

To investigate the development and densification YBa2Cu3O7-x(1-2-3) superconducting phase, the 1-2-3 phase powders have been prepared by citrate and nitrate processes with changing calcination temperature. Nearly pure 1-2-3 phase peaks have been obtained by calcining the precursor in air at 90$0^{\circ}C$ for 2.5h in citrate process but at 95$0^{\circ}C$ for 2.5h in nitrate process. The sintering density of citrate derived sample calcined at 80$0^{\circ}C$ has been about 4% higher than that calcined at 90$0^{\circ}C$, although the compacting density has been lower at 80$0^{\circ}C$ calcination. This can be explained that the 1-2-3 phase particles formed at 80$0^{\circ}C$ have reactive sub-micron size which has good sinterbililty.

• Korean journal of food and cookery science
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• v.23 no.2 s.98
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• pp.245-251
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• 2007

The purpose of this study was to examine how potato glycoalkaloid(PGA) contents changed as storing temperatures and periods changed for potatoes(Superior) cultivated in Korea. Some potatoes were stored at $5^{\circ}$C for 80 days, and others were stored at $20^{\circ}$C for 40 days. PGA contents were measured every 20 days for the potatoes stored at $5^{\circ}$C and 10 days for those stored at $20^{\circ}$C. The results can be summarized as follows. The amounts of a-chaconine and a-solanine measured on the first day of storage were 54.22 mg/100 g and 26.57 mg/100 g, respectively. Thus, the a-chaconine content was almost twice as much as the a-solanine content. The sprouts of potatoes stored at $5^{\circ}$C grew by 0.4 cm in 20 days, 1 cm in 40 days, 1.8 cm in 60 days, and 5.2 cm in 80 days. Furthermore, the PGA content increased by 3.5% in 20 days, 11.6% in 40 days, 23.4% in 60 days, and 41.4% in 80 days, compared to the PGA content on the first day. The sprouts of potatoes stored at 20 grew by 0.5 cm in 10 days, 2.3 cm in 20 days, and 7.4 cm in 40 days. Furthermore, PGA content increased by 12.5% in 10 days, 36.6% in 20 days, 44.8% in 30 days and 48.4% in 40 days, compared to the PGA content on the first day. Thus, we determined that potatoes stored at $20^{\circ}$C showed faster sprout growths and faster increases in PGA content than those stored at $5^{\circ}$C.

• 발명특허
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• v.18 no.2 s.204
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• pp.80-80
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• 1993

• Textile Coloration and Finishing
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• v.6 no.1
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• pp.8-18
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• 1994

In one bath dyeing system of silk/cellulose acetate fiber blend fabric with acid /disperse dyes, adsorption behavior of acid dyes and disperse dyes on silk and cellulose acetate fabrics were examined. In the dyeing of cellulose acetate with C. I. Disperse Red 19(Red 19) and C. I. Disperse Red 60(Red 60) at 8$0^{\circ}C$ and 10$0^{\circ}C$, dye uptake with Red 19 was higher than that with Red 60. When the silk/cellulose acetate dyed with Red 19 and Red 60 at 10$0^{\circ}C$, dye uptake on cellulose acetate was influenced by affinity of the dye to the silk fabric dyed together. When the silk/cellulose acetate dyed with Blue 80/Red 19 and Blue 80/Red 60 at 10$0^{\circ}C$, color of cellulose acetate dyed with Red 19 and Red 60 was not influenced by Blue 80 but silk dyed with Blue 80 was influenced by Red 19 and Red 60. Interrelation of K/S value and Munsell value was scarcely any but showed the change tendency of K/S value.

• Korean Journal of Food Science and Technology
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• v.13 no.3
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• pp.202-208
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• 1981

Contents of moisture, sugar and saponin, and color intensity of red ginseng tea (RGT) prepared at various drying conditions were investigated for quality evaluation. 1. The sorption isotherm of RGT showed step-wise isotherm. 2. The moisture content of RGT dried at $80,\;90\;and\;105^{\circ}C$ reached at nearly constant values below 1.5% after 3 hours. 3. The HPLC patterns of sugar and saponin at various drying temperatures were quality same but different in quantity. 4. The color intensity of RGT was changed little below $80^{\circ}C$, but significantly above $90^{\circ}C$. 5. A significant relationship was found between decrease of sugar content and increase of color intensity above $80^{\circ}C$.

• Journal of Ocean Engineering and Technology
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• v.22 no.1
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• pp.58-63
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• 2008

The effect of alkaline environmental condition on durability of GFRP composites according to additives was investigated. Additives used were polyvinyl alcohol(PVA), kaolin and alumina powder. Weight gains increased with immersion time in all GFRP composites at $80^{\circ}C$. But weight gain of specimen added PVA did not differ through the wlwle immersion time in both tap water and alkaline solution at 20 and $80^{\circ}C$. Tensile strength decreased with immersion time in all environment conditions. Tensile strength of GFRP composites regardless of additives decreased rapidly up to 5 days of immersion and then decreased slowly up to 30 days in alkaline solution environment at $80^{\circ}C$. Weight gains had not. much difference in both tap water and alkaline solution at $20^{\circ}C$. And weight gain of GFRP composites added polyvinyl alcohol had smaller than the others through the whole immersion time in both tap water and alkaline solution at $20^{\circ}C$ and $80^{\circ}C$. Tensile strength of GFRP composites added polyvinyl alcohol had higher than the others through the whole immersion time in both tap water and alkaline solution at $20^{\circ}C$ and $80^{\circ}C$.

• Polymer(Korea)
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• v.36 no.1
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• pp.93-97
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• 2012

Heat treatment effect of polyethylene (PE) separators was investigated after storage at 80, 100 and $120^{\circ}C$ for 1 h. All the samples showed enhanced tensile strength and modulus after heat treatment, but thermal shrinkage up to 15% was observed in PE films having newly formed dimple structure on the surface of fiber after annealed at 100 and $120^{\circ}C$. Although there was 5% of thermal shrinkage after annealing at $80^{\circ}C$, no such serious changes in PE fiber was observed. Furthermore, the separator was found to have enhanced cell performance with 1.3 and 2.3 times higher tensile strength and modulus after heat treatment at $80^{\circ}C$ for 1 h.

• IMMUNE NETWORK
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• v.12 no.6
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• pp.277-283
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• 2012

Vitamin C is an essential water-soluble nutrient which primarily exerts its effect on host defense mechanisms and immune homeostasis, but the mechanism related to immune-potentiation is poorly understood. Since dendritic cells (DCs) are known as a potent antigen presenting cell (APC) that could enhance the antigen specific immune responses, we investigate the effects of vitamin C on activation of DCs and its related mechanism by using dendritic cell lines, DC-1. First, we found that there was no damage on DC-1 by 2.5 mM of vitamin C. In the presence of vitamin C, the expression of CD80, CD86, and MHC molecules was increased, but it was decreased by the pre-treatment of SB203580, p38 MAPK-specific inhibitor. We confirmed the phosphorylation of p38 MAPK was increased by the treatment of vitamin C. Taken together, these results suggest that vitamin C could enhance the activity of dendritic cells via the up-regulation of the expression of CD80, CD86, and MHC molecules and the activation of p38 MAPK is related to this process.

• Korean Journal of Pharmacognosy
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• v.50 no.3
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• pp.175-184
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• 2019

Mast cells are crucial as effector cells in the immediate-type allergic reaction. Lentinus edodes has been the popular edible mushroom in oriental countries and reported to have immunomodulatory, anti-tumor, anti-atherogenic, anti-viral, and anti-allergic activities. However, the roles of L. edodes in mast cell-mediated anaphylactic reaction have not been fully elucidated. In this research, we have demonstrated the effects of the methanol extract of L. edodes (MELE) on mast cell-mediated anaphylaxis-like and anaphylactic reactions. MELE suppressed systemic anaphylaxis-like reaction, plasma histamine levels, and ear swelling response in mice treated with compound 48/80. MELE also suppressed passive systemic and cutaneous anaphylaxis mediated by anti-dinitrophenyl IgE. In accordance with these findings, MELE dose-dependently decreased histamine release from RPMC evoked by compound 48/80 or the antigen-antibody reaction. To clarify the mechanism of degranulation system, intracellular cAMP levels as well as calcium influx in RPMC was evaluated. In compound 48/80-treated RPMC, MELE blocked calcium uptake into the cells. In addition, MELE elevated the intracellular cAMP content and significantly attenuated compound 48/80-induced cAMP reduction in RPMC. Taken together, we propose the clinical use of MELE in mast cell-mediated immediate-type allergic diseases.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.5
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• pp.578-585
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• 1996

Cryo-grinding process comprising hammer mill-shattering and colloid mill-grinding without refrigerant was applied to sardine, pollack and squid muscle frozen at $-20^{\circ}C,\;-40^{\circ}C\;and\;-80^{\circ}C$, respectively and its characteristics were investigated. Particle size distribution of shattered product was shown larger in the order of squid, sardine and pollack and particle size of shattered product frozen at $-80^{\circ}C$ was shown smaller than those at $-40^{\circ}C$. Image of shattered product depended on freezing temperatures and fish species, suggesting particle size distribution of rheological properties can be dependent on fish species or freezing temperature. Yield of cryo- grinded product was in the range of $52.5\~62.5\%$ and Ca content of sardine or pollack product was $6\~8$ times higher than its fillet. Emulsion capacity of cryogrinded product was not decreased during processing. Therefore, this method is thought to be applicable to fish precessing, and preparation of fish paste or powaer.