• Journal of Chest Surgery
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• v.18 no.4
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• pp.732-739
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• 1985

This study was experimentally undertaken to evaluate the effect of the coronary vasodilator-mixed cardioplegic solution on myocardial protection during prolonged aortic cross-clamping. The dogs were divided into two groups: control group A[received hypothermic cardioplegic solution without any additive coronary vasodilator], and comparing group 8[received hypothermic cardioplegic solution, mixed with various coronary vasodilators and Inderal]. Group A further was divided into two subgroups: subgroup A-1[ischemic time, 90 minutes], and subgroup A-2 [ischemic time, 240 minutes]. Group B further was divided into five subgroups: subgroup B-1 [received papaverine mixed hypothermic cardioplegic solution], subgroup B-2[received nitroglycerin mixed hypothermic cardioplegic solution], subgroup B-3 [received nitroprusside mixed hypothermic cardioplegic solution, subgroup B-4[received hydralazine mixed hypothermic cardioplegic solution], and subgroup B-5 [received inderal mixed hypothermic cardioplegic solution]. The specimens from all of the subgroups were studied by electron microscopic examination. The specimens of subgroups [B-l, B-2 8-3, and B-4], received coronary vasodilators mixed hypothermic cardioplegic solutions, were also compared by methylene blue induced staining of the myocardium and coronary vessels. The results obtained were as followings: l. On electron microscopic examination, all of the specimens, including subgroup A-2, showed no irreversible change of the myocardium. But the best result was obtained from the subgroup B-l, treated by papaverine mixed hypothermic cardioplegic solution. The subgroup B-2, treated by nitroglycerin, was next. And the subgroup B-5, treated by Inderal, was agreeable, comparing the electron microscopic finding with control group in the effect of myocardial protection. 2. The distribution in the myocardium of cardioplegic solution was demonstrated with the aid of methylene blue staining in the subgroups of B-l, B-2, B-3, and B-4, and they were the groups treated by papaverine, nitroglycerin, nitroprusside, and hydralazine in their grouping order. The best result was obtained from the subgroup B-1 [papaverine]. The subgroup B-2 [nitroglycerin] was next. The subgroup B-3 [nitroprusside] was moderate in finding of the colorization. The subgroup B-4 [hydralazine] was the poorest in the distribution of the cardioplegic solution in the myocardium. From these results, it appeared that myocardial protection during ischemic arrest for open heart surgery could be enhanced considerably when coronary dilatation was assured.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1359-1365
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• 2010

This study investigated effects of types of added sugar on alcohol fermentation of oriental melon. According to the results, pH was not significantly different according to types of added sugar and fermentation process. Total acidity increased with fermentation process in all groups by recording around 1.4% at the ninth day of fermentation. For sugar content, its initial level was $22^{\circ}Brix$, and alcohol fermented oriental melon fluids added by sucrose, fructose and glucose recorded similar levels or $6.6{\sim}6.8^{\circ}Brix$ while the fluids added by honey and fructo-oligosaccharide showed a slightly higher level or $8.1^{\circ}Brix$ at the ninth day of fermentation. Although free sugar content was different in the early phase of fermentation according to types of added sugar such as sucrose, fructose and glucose, it reduced with fermentation process to nearly non-detection at the ninth day of fermentation. As organic acids, lactic acid and acetic acid were observed in all phases of fermentation and their contents became higher gradually with fermentation process. Alcohol content showed the highest level in alcohol fermented oriental melon fluid added by sucrose by recording 12.80% and was relatively low in the fluids added by fructose and oligosaccharide. For alcohol, acetaldehyde, n-propanol and iso- amylalcohol contents were not significantly different according to types of added sugar and methanol content was the lowest in the fluid added by fructose by recording 84.99 ppm.

• Applied Chemistry for Engineering
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• v.5 no.3
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• pp.547-559
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• 1994

To effectively utilize fish skin wastes from marine manufactory, the optimal extraction conditions to prepare gelatin from fish skins of Alaska pollack, cod and yellowfin sole were investigated. In addition, the physical properties of the fish skin gelatins prepared under the optimal extraction conditions were compared with the commercial animal skin gelatin. The conditions for extraction of gelatins from fish skins were as follows ; The skins were limed with 1.0~1.5%(w/v) calcium hydroxide solution. The fish skin gelatins were extracted with 6~7 volumes of water(pH 6.0~7.0) for 5hrs at $40{\sim}50^{\circ}C$, and the yield of Alaska pollack skin gelatin extracted under the above conditions was higher than those of cod and yellowfin sole skins. The heavy metal contents, jelly strength and electric conductivities of fish skin gelatins were lower than those of a commercial gelatin(bovine skin), but the viscosity and isoelectric point were higher. The amount of amino acid in fish skin, such as gelatin, glutamic acid, serine, threonine, methionine and cysteine, were higher than those in pig and ox skin. However, the contents of hydroxyproline and proline were lower.

• Journal of Plant Biotechnology
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• v.40 no.4
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• pp.203-209
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• 2013

Genetic manipulation of pear (Pyrus pyrifolia Nakai) breeding is still difficult due to lack of reliable regeneration system. The aim of this research is to establish shoot regeneration system from leaf explants for pear (P. pyrifolia cv. Niitaka) using various concentrations of plant growth regulators and carbon source supplemented to medium. The highest regeneration rate of about 20% was found on a medium containing 4.4 g/L of Murashige and Skoog (MS) without vitamins, Linsmaier and Skoog (LS) vitamins were added separately. Leaf explants of pear were cultured on MS medium containing 7 g/L of Daishin agar supplemented with various concentrations of NAA (0.01, 0.05, 0.1, 0.5 mg/L) in combination with BA(3, 5, 10 mg/L) for shoot regeneration. In medium with 5 mg/L of BA and 0.01 mg/L of NAA, adventitious shoot regeneration rate was higher than others treated. The optimal results were observed using MS medium supplemented with 30 g/L sorbitol as carbon source on regeneration system. Sorbitol is considered better carbon source than sucrose for shoot regeneration of pear (P. pyrifolia cv. Niitaka). In order to increase of shoot regeneration in pear (P. pyrifolia cv. Niitaka), plant agar and Daishin agar used as gelling agents, Daishin agar is more efficient in shoot regeneration.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.739-748
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• 2021

This study focuses on the use of rice in the production of gluten-free rice udon (GFU) through an optimized mixing ratio, using the Box-Behnken response surface methodology (RSM). Different additional levels of rice flour (A, 40-60 g), acetylated distarch adipate (B, 10-20 g), and trehalose (C, 0-3 g) were used as variables, while water absorption level, volume, cooking loss, solid yield, lightness, texture properties, proximate compositions of GFU and turbidity of cooking water were set as responses in the RSM design model. The optimum mixing ratio for the preparation of gluten-free rice udon was obtained for 60.00 g of rice flour, 18.81 g of acetylated distarch adipate without the addition of trehalose. The response values of the optimized samples were water absorption (60.94%), volume (34.94%), turbidity of the cooking water (0.37), cooking loss (4.77%), solid yield (1.55 g), lightness value (70.04), hardness (2.53 N), springiness (0.18), gumminess (10.45 N), chewiness (1.83 N), and cohesiveness (2.89). This study has shown that rice flour can replace wheat flour to manufacture udon at an optimized mixing ratio successfully derived by statistical estimation method.

• Journal of the Korean Chemical Society
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• v.44 no.5
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• pp.453-459
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• 2000

FED has deserved an intensive attentioD as a new flat panel display. The present investigationaims at undemtanding the photoluminescence and cathodoluminescent properties of hGaO$_3$: $Eu^{3+}$ phosphor bytaking into account the possibility that this phosphor could be applied for FED. In onler to investigate on.sucha detailed behavior; 8everM experimental skil18 Je conducted to the LaGaO$_3$:$Eu^{3+}$ phosphoL The excimtion srectrum artd emission spectmn were rnezsured in the UV range and then decay curve of $^5D_0$+$^7F_j$transitions\vas examined. The decay behavior of $^5D_0$ emission was anMyzed by a newly Iuoposed cross-relaxation mech-ani8In in asswiation with inteFwnter di1ffision (or migration). The cross-mlaxation from $^5D_0$ to CTB (Cha'geTransfer Band) wuld be a quite retsonable by considering the excitation spectrum. It could be also found thatthe quenching type was changed from ditfrsion controlled process to the direct quenching process -s inJeasing $Eu^{3+}$ oncntration.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.489-495
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• 2016

In this study, the Warm-Mix Asphalt was prepared using a modified Sulfur Binder mixed with an additive of a polymer component in sulfur, which is an industrial by-product generated in the crude oil refining process. The dynamic stability and durability characteristics of the prepared Warm-Mix Asphalt was evaluated by the indirect tensile strength, the tensile strength ratio before and after water immersion and freezing-thawing, and the dynamic stability by wheel tracking test. The Warm-Mix Asphalt Mixtures using Modified Sulfur Binder has a tensile strength ratio before and after water immersion of 0.88, which is about 1.13 times that of the Warm-Mix formed modified Asphalt, and the tensile strength ration before and after freezing-thawing is also 0.82, thus, all tensile strength ratios satisfied the KS quality standard value of 0.75 or more. The indirect tensile strength was 1.6MPa which was twice the KS quality standard value of 0.8MPa, and about 1.24 times higher than that of normal heated asphalt 1.29MPa. In addition, the dynamic stability by the wheel tracking test was 14,075 times/mm, which was about 15 times higher than that of normal heated asphalt and about 3 times higher than that of the Warm-Mix formed modified Asphalt, showing excellent resistance to plastic deformation such as fatigue cracks.

• Resources Recycling
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• v.15 no.4 s.72
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• pp.44-51
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• 2006

Most electric arc furnace dust (EAFD) treatment processes to recover zinc from EAFD employ carbon as a reducing agent for the zinc oxide in the EAFD. In the present work, the reduction reaction of zinc oxide with carbon in the present of iron oxide was kinetically studied. The experiments were carried out at temperatures between 1173 K and 1373 K under nitrogen atmosphere using a weight-loss technique. From the experimental results, it was concluded that adding the proper amount of iron oxide to the reactant accelerates the reaction rate of zinc oxide with carbon. This is because iron oxide in the reduction reaction of zinc oxide with carbon promotes the carbon gasification reaction. The spherical shrinking core model for a surface chemical reaction control was found to be useful in describing kinetics of the reaction over the entire temperature range. The reaction has an activation energy of 53 kcal/mol (224 kJ/mol) for ZnO-C reaction system, an activation energy of 42 kcal/mol (175 kJ/mol) for $ZnO-Fe_{2}O_{3}-C$ reaction system, and an activation energy of 44 kcal/mol (184 kJ/mol) for ZnO-mill scale-C reaction system.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.9
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• pp.900-906
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• 2008

It was studied to utilize wasted food as a starting material to produce for activated carbon. The wasted food was chemically activated with zinc chloride. Experiments were carried out at different chemical ratios(activating agent/wasted foods), activation temperatures, and activation time. The activated products were characterized by measuring the iodine and methylene blue number, the BET surface area, the pore volume, the micropore ratio, the pore diameter, the yields and the scanning electron microscope(SEM). For the products activated by impregnation ratio of 1.0 of ZnCl$_2$ at 500$^{\circ}C$ for 60 min in a rotary kiln reactor had iodine number of 480 mg/g, methylene blue number of 95 mL/g, BET surface area of 410 m$^2$/g, pore volume of 0.248 cm$^3$/g, and average pore diameter of 2.43 nm, respectively. The activated carbon obtained had the contribution of micropore area of 70.7% to the total pore area and micropore volume of 53.2% to the total pore volume.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.556-564
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• 2018

In this study, polyethylene oxide (PEO)/polyethylene-co-vinyl acetate (EVA)/multi-walled carbon nanotube (MWCNT)-COOH composite membranes were prepared by adding 1, 2, 3, and 5 wt% of MWCNT-COOH to PEO/EVA respectively. The gas permeation properties of $N_2$, $O_2$ and $CO_2$ at $30^{\circ}C$ and 4~8 bar pressure were investigated. In each PEO/EVA/MWCNT-COOH composite membranes, the permeability of $CO_2$ increased with increasing the pressure, but the permeability of $N_2$ and $O_2$ were independent of the feeding pressure. As the MWCNT-COOH content increased, the $CO_2$ permeability increased and then decreased above 2 wt% MWCNT-COOH content. The 2 wt% MWCNT-COOH composite membrane exhibited a $CO_2/N_2$ selectivity of 77.8 and a $CO_2$ permeability of 84 barrer at 8 bar. The high $CO_2/N_2$ selectivity and $CO_2$ permeability were due to the high affinity between the quadrupolar $CO_2$, polar ether groups of PEO, and the polar ester groups of EVA. Additionally, the strong affinity between $CO_2$ and the -COOH groups on the MWCNT surface contributed to the high permeability of $CO_2$.