• Transactions of the Korean hydrogen and new energy society
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• v.25 no.6
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• pp.636-642
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• 2014

As environment problem became a worldwide issue, countries are tightening regulations regarding greenhouse gas reduction and improvement of air pollution problems. With these circumstances, one of the renewable energies produced from biomass is getting attention. Bio-ethanol, which is applicable to SI engine, showed a positive effect on the PFI (Port Fuel Injection) type. However, Ethanol has a problem in homogeneous mixture formation because it has high latent heat of vaporization characteristics and in the GDI (Gasoline Direct Injection) type, mixture formation is required quickly after fuel injection. Particularly, South Korea is one of the countries with great temperature variation among seasons. With this reason, South Korea supply fuel additive for smooth engine operation during winter. Therefore, experimental study and investigation about application possibility of blending fuel is necessary. This paper demonstrates the spray characteristics by using the CVC direct injection and setting the bio-ethanol blending fuel temperature close to the temperature during each seasons: -7, 25, $35^{\circ}C$. The diameter and the width of the CVC are 86mm and 39mm. High-pressure fuel supply system was used for target injection pressure. High-speed camera was used for spray visualization. The experiment was conducted by setting the injection pressure and ambient pressure according to each temperature of bio-ethanol blending fuel as a parameter. The result of spray visualization experiment demonstrates that as the temperature of the fuel is lower, the atomization quality is lower, and this increase spray penetration and make mixture formation difficult. Injection strategy according to fuel temperature and bio-ethanol blending rate is needed for improving characteristics.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.189-189
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• 2015

In this study, the corrosion resistance and adhesion of electrophoretic paint (E-paint) were studied on AZ31 magnesium alloy pretreated in cerium chemical conversion coating solutions with the addition of various ethanol concentrations. It was found that with increasing ethanol concentration from 0 to 90 percent can decrease the formation of $Mg(OH)_2/MgO$ and increase the formation of nano-crystalline cerium oxides on the coating. Both corrosion resistance and adhesion of E-painted AZ31 increased with increasing ethanol concentration. The best E-paint sample was observed on the sample pretreatment in cerium chemical conversion coating solution with the addition of 80 percent of ethanol. This sample showed an excellent adhesion without paint detached after water immersion test for 500 h at $40^{\circ}C$, and only a few blisters observed at the near scratched sites after 1000 h salt-spray test.

• Journal of the Korean Wood Science and Technology
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• v.50 no.6
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• pp.448-457
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• 2022

Yersinia enterocolitica, which causes yersiniosis, is a bacterium that produces biofilms effectively. The inhibition of biofilm formation provides a method for preventing infections with Y. enterocolitica. In this study, the inhibitory activity of Y. enterocolitica biofilm formation was investigated in a library of 140 edible plant methanol extracts including forest products. It was identified that the biofilm formation could be inhibited by 12 extracts of plants, Agastachis Herba, Agrimoniae Herba, Diospyros kaki leaves, Elsholtziae Herba, Ginkgonis Semen, Lycopi Herba, Melonis Pedicellus, Menthae Herba, Mori Radicis Cortex, Polygoni Multiflori Radix, Prunellae Spica, and Schizonepetae Spica. After changing the solvent to ethanol and water, the greatest inhibition of biofilm formation was produced by a 50% ethanol extract of Polygoni Multiflori Radix. A method to effectively prevent yersiniosis can be developed using the edible plant extracts identified in this study.

• Journal of the Korean Chemical Society
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• v.19 no.6
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• pp.423-427
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• 1975

Changes in the electrical conductivity of gallium doped zinc oxide during the dehydrogenative oxidation of ethanol between 250 and $350^{\circ}C$ have been studied. Both dehydrogenation and dehydration of ethanol takes place on ZnO. At $300^{\circ}C$ and above formation of $CO_2$ was observed accompanied by an increase in the electrical conductivity. This seems to be due to oxidation of CO formed by the decomposition of acetaldehyde. Addition of oxygen to ethanol increases the amount of acetaldehyde formed, while no change is observed in ethylene formation. It may be that oxygen which is present primarily as $O^-$ provides a favorable site for the adsorption of ethanol and for subsequent hydrogen substraction.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.311-314
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• 2007

Citrus sunki Hort. ex Tanaka is one of several Jeju-native citrus fruits. A number of biological properties for citrus fruits have been suggested, however little is known about those of C. sunki. The present study tested whether fermented product of C. sunki peel (FSP) might affect the activities of enzymes regulating ethanol metabolism. Effects on body weight gain as well as on fatty liver formation were also investigated. The activities of alcohol dehydrogenase and aldehyde dehydrogenase were stimulated remarkably by FSP. Excessive ethanol-induced cytotoxicity was also prevented by FSP in HepG2 cells. FSP decreased the weight gain and fatty liver formation induced by a high-fat diet in mice. From these results, FSP might be a potent source of neutraceuticals useful for preventing ethanol-induced health problems.

• Toxicological Research
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• v.11 no.2
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• pp.267-271
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• 1995

A single large dose of ethanol as well as chronic ethanol consumption produces alcoholic fatty liver in human and experimental animals. We examined the effects of YH439, a potential hepatoprotective agent, on alcoholic fatty liver generation in adult female rats. In rats treated with YH439 (250 mg/kg, po) 4 hr prior to a single dose of ethanol (6 g/kg, po), a significant decrease in hepatic triglyceride accumulation was observed. YH439 also has an inhibitory effect on hepatic triglyceride and cholesterol accumulation induced by repeated ethanol treatments for one week. Because it has been known that induction of alcoholic fatty liver is associated with lipid peroxidation and/or hepatic glutathione depression, the effect of YH439 on these parameters was determined in the livers of rats treated with ethanol. Coadministration with YH439 inhibited MDA formation and gIutathione depression induced by acute or repeated ethanol administration. In order to determine the effect of YH439 on ethanol metabolism in vivo, disappearance of ethanol from blood was measured. In rats treated with a single dose of ethanol (6 g/kg, po), the ethanol concentration in blood reached a peak approximately 120 min following the treatment which declined linearly for 18 hrs. YH439 had no effect on the decline of blood ethanol concentration regardless of the dose of ethanol given to rats. These results in this study suggest that YH439 has an inhibitory effect on fatty liver generation induced by acute or repeated ethanol consumption through a mechanism not directly related to the rate of ethanol metabolism in vivo.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.3
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• pp.371-384
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• 1995

Ethanol can affect a wide range of organ and organelle systems. Some of its effects are directly due to the action of either ethanol or its metabolites, whereas others are related to nutritional deficencies associated with ethanol intake. Some of the liver damages occurring in alcohol abusers are mainly due to generation of free radical during the metabolism of ethanol and subsequent lipid peroxidation. Acetthrough the formation of free radicals, or depletion of levels of antioxidant substances. When prevent generation of the activity. Several authors have reproted the ethanol-related variation of antioxidants such as $\alpha$-tocopherol, ascorbic acid, selenium and glutathionem which are important thereby promoting deficiencies as well as toxic interactions with vitamin A and $\beta$-carotene. It has been appeared that ethanol-induced hepatotoxicity may be partially prevented by the administration of antioxidants.

• Journal of the Korean Chemical Society
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• v.9 no.3
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• pp.148-151
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• 1965

Kinetics of reactions of chloride and bromide ions with benzyl chloride and bromide have been investigated in 90% ethanol solution. Semi-quantitative analysis of the results shows that the bond-formation is more important than the bond-breaking and furthermore in bond-formation the energy gain due to bond-formation is less than the increase in electron affinity of the nucleophile.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.657-664
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• 2004

In this study, a fundamental experiment was carried out to investigate the frost formation on a cryogenic flat plate with/without temperature distribution from 230K to 160K under the convective flow. The effects of mixing ethanol as a condensable substance were also researched. From the test results, when surface temperature at the upstream is 230K, mass flux is high. On the other hand, when surface temperature at the downstream is 160K, mass flux is low. The degree of improvement to restrain frost formation by ethanol mixing is relatively larger at the upstream than at the downstream.

• Bulletin of the Korean Chemical Society
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• v.22 no.3
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• pp.276-280
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• 2001

The self-assembled formation of octadecanethiol (CH3(CH2)17SH) on a gold substrate was studied using a quartz crystal microbalance (QCM) and a scanning tunneling microscope (STM). From the QCM measurements at vario us concentrations of octadecanethiol solutions in hexane and alcohol, the adsorption process of octadecanethiol onto Au was confirmed to consist of two steps as follows: (i) fast but disordered adsorption and (ii) a thermodynamically controlled rearrangement for uniform packing of octadecanethiol. Also, it was revealed that the adsorption rate became faster in ethanol than in hexane since less solubility of octadecanethiol in ethanol could help the formation of the monolayers. At 5 ${\times}$10-7 M solution, the monolayer formation was monitored by STM. The morphology of monolayer region was initially circular (diameter size: 7.26 $\pm$ 2.1 nm) and gradually changed to a stripe type after several minutes. At higher concentration, the self-assembled monolayer was formed immediately after the solution was introduced to a substrate.