• 한국응용과학기술학회지
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• 제24권4호
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• pp.377-382
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• 2007

We designed capacitance sensor in order to examine characteristics of W/O type emulsified fuel, so it concluded the following conclusions. The capacitance value of emulsified fuel, using with capacitance sensor, increases as water content increases due to the coalescence. When surfactant increases, the capacitance value decreases, the condition of W/O type emulsified fuel was maintained stably. There was revealed the capacitance value difference of W/O type emulsified fuel in in according to water content. We checked the phase separation of emulsified fuel with the capacitance value difference. The surfactant(HLB=5.4) had better stable condition than surfactant(HLB=4.3). Also, we confirmed that two mixture surfactants were better than one surfactant.

• 한국응용과학기술학회지
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• 제37권5호
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• pp.1248-1256
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• 2020

In this study, the polyurethane resin was synthesized by applying PTMG and DMBA of different composition ratios for the synthesis of water-dispersible polyurethane used in wound coating resin. The varying properties of the synthesized water-dispersible polyurethane were measured through tensile strength, elongation, and abrasion resistance analysis. As for the tensile strength measurement result according to the PTMG content, the sample with the highest reaction molar ratio was measured as 1.08 kgf/mm2 and the elongation was measured as 520%. As for the tensile strength result according to the DMBA content, the sample with the highest reaction molar ratio was measured as 0.51 kgf/mm2, and the elongation was measured as 435%. The degree of surface destruction by the abrasion resistance measurement was visually confirmed through SEM.

• 한국응용과학기술학회지
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• 제20권4호
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• pp.275-282
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• 2003

Aqueous polyurethane dispersion was synthesized using phosphorus compound which received significant attention for the replacement of halogenated flame retardants. In this study, polyols which have phosphorus moity in their structural unit were synthesized by two-step polycondensation reaction using dimethyl phenylphosphonate, ethylene glycols. adipic acid, and 1,4-butanediol. In the next step, polyurethane dispersion was prepared using these polyols, isophorone diisocyanate with dimethyl propionic acid. The particle size of polyurethane latex was reduced from 347 nm to 240 nm with increasing DMPA content. It was observed that the LOI values of prepared coatings increased from 27% to 35% with increasing phosphorus content.

• 한국응용과학기술학회지
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• 제25권3호
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• pp.347-354
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• 2008

This study was done to investigate the antidiabetic effect of polygoni radix in Streptozotocin(STZ)-induced diabetic rats. Diabetes was induced by intravenous injection of STZ at a dose of 45mg/kg dissolved in citrate buffer. The ethanol extract of polygoni radix was orally administrated once a day for 7 days. The content of serum glucose, triglyceride(TG), total cholesterol were significantly decreased in polygoni radix treated STZ-sample group compared to the those of STZ-control group. The content of hepatic glycogen and activities of glucose-6-phosphate dehydrogenase(Glucose-6-PDH), glucokinase were significantly increased, but activity of glucose-6-phoshatase was decreased in polygoni radix treated STZ-sample group compared to the those of STZ-control group. These results indicated that ethanol extract of polygoni radix would have antidiabetic effect in STZ-induced diabetic rats.

• 한국응용과학기술학회지
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• 제16권1호
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• pp.45-57
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• 1999

This study was designed to examine the effect of ${\omega}-3$ fatty acid, linlenic acid, EPA, DHA on serum lipid and cytokines of male rats(Sprague-Dawley). Animals of 3 groups were administrated perilla oil, salmoon oil, and tuna oil of 0.4 $m{\ell}/day$ for 8 weeks respectively. These oils were used for a source of linolenic acid, EPA and DHA. ${\omega}-3$ polyunsaturated fatty acid decreases significantly body weight, serum $PGE_2$ content and serum cytokines content of the rat, and increases internal organs weight, specially liver weight and serum HDL-cholesterol level of the rat. In the results, authors propose to use perilla oil for source of effective ${\omega}-3$ poly-unsaturated fatty acid(linolenic acid) to Prevent cardiovascular and immune diseases.

• Food Science and Biotechnology
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• 제14권3호
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• pp.363-367
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• 2005

Although widely applied in the food industry, extrusion cooking has not been applied to the traditional red ginseng process for steaming and drying ginseng. We therefore investigated the change in the effective components in red ginseng (total saponins, ginsenosides and maltol) from extruded raw ginseng. The variables were the drying temperature of the sliced raw ginseng (80 and $90^{\circ}C$) before the extrusion process and the moisture content (15 and 22%, w.b.) during the extrusion process. Ginsenosides Rg1 and Rg2 were detected in dried ginseng at $80^{\circ}C$, but ginsenoside Rg3, which was contained in red ginseng, was not detected. On the other hand, ginsenosides Rg1, Rg2 and Rg3 were detected in extruded ginseng at moisture contents of 15 and 22%. Total ginsenosides were highest at $90^{\circ}C$ drying temperature and 22% moisture content for the extrusion process.

• 한국응용과학기술학회지
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• 제27권3호
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• pp.223-232
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• 2010

The effects of HLB value of nonionic mixed surfactants on the stability and antifoaming ability for silicon oil type emulsions were studied. To obtain a stable silicone emulsions, a higher HLB values and higher content of surfactants were preferred. To obtain a good antifoaming ability, however, a lower HLB value (more hydrophobic) and a lower content of the surfactants were preferred. It was observed, at lower HLB values(8 or 9), that the silicone oil drops were spreaded on the foam surface and effectively reduced the surface tension. And the spreading phenomena presumably acted as an antifoaming mechanism. Therefore, a higher hydrophobicity of the silicone oil emulsion resulted in a higher ability of antifoaming action.

• 한국응용과학기술학회지
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• 제40권4호
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• pp.699-709
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• 2023

This study is to establish optimizing condition of alcohol fermentation in vinegar production with aronia, to confirm whether this can be industrially used, and to compare and analyze a change in anti-oxidative activity and quality characteristic according to alcohol fermentation of aronia. The optimized conditions for alcohol fermentation were as follows: Saccharomyces cerevisiae 5645 of yeast strain, a 5% inoculum size, aronia juice with a brix value of 14, and a glucose content of 7%. As a result to conduct scale up with optimizing conditions of alcohol fermentation of aronia, 8 days (192 hrs) of total alcohol fermentation time and 7.4% of the final alcohol content. The harvest volume accounted for approximately 90.2% with a loss of about 2.8%. As a result of antioxidant test, anti-oxidative activity of alcohol fermented liquor is lower than anti-oxidative activity of aronia extract, because of the decrease of antioxidant by oxidation of the fermentation process. However, the decrease of tannin by the fermentation process reduces acerbity of aronia, so increases overall preference

• 한국약용작물학회지
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• 제21권1호
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• pp.39-44
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• 2013

This study was conducted to identify the effect of shading and pinching on growth and acanthoside-D content of Acanthopanax divaricatus var. albeofructus and A. koreanum Nakai. Different pinching heights showed no significant differences in terms of plant growth and acanthoside-D content but higher values showed that pinching A. divaricatus at 60 cm and A. koreanum at 30 cm favored good growth and higher fresh weight in the shoots. The content of acanthoside-D was not significantly affected by pinching heights. Also, no significant difference in acanthoside-D content was found between the lower and upper part of plant in the first year. However it was much higher in the lower part than the upper part in the second year, which indicated that the content of acanthoside-D was comparatively high in the lower part where lignification is much advanced. Shading showed benefits in terms of growth of A. divaricatus while only 50%-shading was favorable for A. koreanum to achieve superior growth. Overall, results indicated that shading had favorably affected the growth of the 2 Acanthopanax species while no-shading is better if we opt to achieve higher acathoside D content.

• Carbon letters
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• 제20권
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• pp.39-46
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• 2016

In this work, the effects of maleic anhydride (MA) content on mechanical properties of chopped carbon fibers (CFs)-reinforced MA-grafted-polypropylene (MAPP) matrix composites. A direct oxyfluorination on CF surfaces was applied to increase the interfacial strength between the CFs and MAPP matrix. The mechanical properties of the CFs/MAPP composites are likely to be different in terms of MA content. Surface characteristics were observed by scanning electron microscope, Fourier transform infrared spectroscopy, and single fiber contact angle method. The mechanical properties of the composites were also measured by a critical stress intensity factor (K_IC). From the K_IC test results, the K_IC values were increased to a maximum value of 3.4 MPa with the 0.1 % of MA in the PP, and then decreased with higher MA content.