• 한국분무공학회지
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• 제22권3호
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• pp.109-115
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• 2017

The aim of this study is to investigate the effect of physical properties of fuels on spray characteristics in the gasoline direct injection system. Injection rate, spray visualization, and spray pattern experiments were performed to analyze the spray characteristics of ethanol, gasoline, and ethanol/gasoline blends. We measured injection rate of each fuel via the Bosch method. The spray visualization experiment was also carried out at atmospheric pressure using a high-speed camera. Finally, the average of drop surface area per unit volume was measured using the optical patternator. The experimental results from Bosch method showed that peak injection rate increased when the volume fraction of ethanol increased. In addition, higher viscosity of ethanol than that of gasoline leads to longer injection delay. At the initial injection region before reaching 0.8 ms, the spray tip penetration becomes longer as increasing the volume fraction of ethanol, but reversely shorter after 0.8 ms. It was found that ethanol makes spray angle become larger. The surface area per unit volume of the drop was decreased as the distance from the injection tip or the concentration of the gasoline increased.

• 대한약리학회지
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• 제15권1_2호
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• pp.21-27
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• 1979

It is well known that picrotoxin, an amaroid substance of Anamirta cocculus, is a classic stimulant on the central nervous system accompanying convulsive activity, and it liberates catecholameine from the adrenal mdulla through its central action to increase blood sugar level. Schou reported that lithium and alcohol have the similar inhibitory property on the $Na^+,\;K^+$-ATPase activity, and recently, the therapeutic efficacies of lithium on the alcohol withdrawal syndrome and the chronic alcoholics have been studied. Many studies about the hypoglycemic effect of lithium and alcohol were reported but the interaction between those hypoglycemic action is little known. Therefore, in this paper, the hypoglycemic effect of lithium and ethanol on the hyperglycemia induced with picrotoxin, and the interaction of them in those hypoglycemic action were investigated with reference to the anticonvulsive action of them. The results were obtained as follows: 1. The convulsive dose (: $CD__{50}$) of picrotoxin in mice was slightly increased by the pretreatment of lithium or ethanol. 2. The blood sugar level was markedly increased by picrotoxin but the level was sugar level was significantly decreased by lithium, ethanol or both. 3. The hyperglycemic effect of picrotoxin was significantly potentiated by the lithium pretreatment, but the potentiation effect of lithium was markedly suppressed by the additional injection of ethanol after lithium injection and more markedly suppressed by the premedication of ethanol before lithium injection 4. The hyperglycemic effect of picrotoxin was markedly inhibited by the ethanol pretreatment, and the inhibitory effect of ethanol was significantly strenthened by the additional injection of lithium after ethanol injection, but on the contrary, the inhibitory effect was completely disappeared by the premedication of lithium before ethanol injection.

• 대한약리학회지
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• 제30권2호
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• pp.217-225
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• 1994

In an attempt to define the effects of Biphenyldimethyl dicarboxylate(DDB) on the lipid peroxidation, oxygen free radical scavenging enzymes activities and hepatic functions in ethanol-induced hepatotoxic rats, we studies malondialdehyde(MDA) level and the activities of catalse, superoxide dismutase(SOD), glutamic-oxaloacetic transaminase(GOT) and glutamic-pyruvic transaminase(GPT) in liver of the rats at 24, 48 and 72 hr after the injection of ethanol and DDB. Sprague-Dalwey albino rats weighing 250 to 280gm were injected intraperitoneally with ethanol(2.5 gm/kg ) only and ethanol plus DDB(300mg/kg ). The result obtained can be summarized as follows : 1) The group treated with ethanol showed significantly higher MDA level and lower catalase and SOD activities at 24, 48 and 72hr after the injection as compared with that of control group. 2) The group treated with ethanol showed significantly higher GOT and GPT activities at 24, 48 and 72hr after the injection as compared with that of control group. 3) The group treated with ethanol plus DDB showed significantly lower MDA level and higher catalase and SOD activities at 24, 48 and 72 hr after the injection as compared with that of ethanol group. 4) The group treated with ethanol plus DDB showed significantly lower GOT and GPT activities at 24, 48 and 72 hr after the injection as compared with that of ethanol group. These results suggest that the excessive oxygen free radicals resulting from the depression of the activities of catalase and superoxide dismutase is an important determinant in pathogenesis of ethanol-induced hepatotoxicity and DDB has antioxidant effects.

• 한국자동차공학회논문집
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• 제17권4호
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• pp.55-62
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• 2009

As an experiment investigation, the effects of ethanol blended gasoline fuel with different injection method on nano-sized particle emission characteristics were examined in a 0.5L spark-ignited single-cylinder engine with a compression ratio of 10. Because this engine nano-particles are currently attracting interest due to its adverse health effects and their impact on the environments. So a pure gasoline and an ethanol blended gasoline fuels, namely E85 fuel, used for this study. And, as a particle measuring instrument, a fast-response particle spectrometer (DMS 500) with heated sample line was used for continuous measurement of the particle size and number distribution in the size range of 5 to 1000nm (aerodynamic diameter). As this research results, we found that the effect of ethanol blending gasoline caused drastic decrease of nano-particle emissions when port fuel injection was used for making better air-fuel mixture than direct fuel injection. Also injection timing, specially direct fuel injection, could be a dominant factor in controlling the exhaust particle emissions.

• 한국분무공학회지
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• 제17권1호
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• pp.1-8
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• 2012

This study described the effect of the multiple injections and diesel-ethanol on the NVH, combustion and emission characteristics of 4 cylinder common rail diesel engine. In order to investigate the influence of diesel-ethanol blended fuel in a light-duty common rail diesel engine, the injection strategy was varied with pilot injection, double pilot injections, and one main injection at various operating conditions. The results showed that diesel-ethanol blended fuel had longer ignition delay than that of the ultra low diesel fuel(ULSD). Also, in the case of multiple injections, the combustion pressure is increased smoothly near the TDC and the NVH are decreased. In the emission characteristics, diesel-ethanol blended fuel produced lower indicated specific nitrogen oxides(IS-NOX) and indicated specific Soot(IS-soot) emissions, however, indicated specific unburned hydrocarbon(IS-HC) and indicated specific carbon monoxide(IS-CO) emissions are slightly increased.

• 한국수소및신에너지학회논문집
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• 제25권6호
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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.

• 한국자동차공학회논문집
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• 제17권5호
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• pp.61-66
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• 2009

An experimental investigation was conducted to analyze the effects of biodiesel-ethanol and biodiesel-diesel blended fuels on the characteristics of combustion and exhaust emissions, and size distributions of particulate matter in a single cylinder diesel engine. The three types of test fuel were biodiesel and two blended fuels which were added ethanol and diesel by 20 % volume based fraction into biodiesel, respectively. In this study, the injection rate, combustion pressure, exhaust emissions and size distributions of particulate matter were measured under various injection timings and injection pressures. The experimental results show that biodiesel-ethanol blended fuel has lengthened ignition delay and low combustion pressure in comparison with those of biodiesel and biodiesel-diesel blended fuel even if all fuels indicated similar trends of injection rate under equal injection pressures. In addition, the ethanol blended fuel significantly reduced nitrogen oxidies (NOx) and soot emissions. And then the size distribution of particulate matters shows that blended fuels restrain the formation of particles which were beyond the range of 150nm comparison with biodiesel fuel.

• 한국자동차공학회논문집
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• 제22권4호
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• pp.1-9
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• 2014

The vast stores of biomass available in the worldwide have the potential to displace significant amounts of petroleum fuels. Fast pyrolysis of biomass is one of several paths by which we can convert biomass to higher value products. The wood pyrolysis oil (WPO) has been regarded as an alternative fuel for petroleum fuels to be used in diesel engine. However, the use of WPO in a diesel engine requires modifications due to low energy density, high water contents, high acidity, high viscosity, and low cetane number of the WPO. One possible method by which the shortcomings may be circumvented is to co-fire WPO with other petroleum fuels. WPO has poor miscibility with light petroleum fuel oils; the most suitable candidates fuels for direct fuel mixing are methanol or ethanol. Early mixing with methanol or ethanol has the added benefit of significantly improving the storage and handling properties of the WPO. For separate injection co-firing, a WPO-ethanol blended fuel can be fired through diesel pilot injection in a dual-injection dieel engine. In this study, the performance and emission characteristics of a dual-injection diesel engine fuelled with diesel (pilot injection) and WPO-ethanol blend (main injection) were experimentally investigated. Results showed that although stable engine operation was possible with separate injection co-firing, the fuel conversion efficiency was slightly decreased due to high water contents of WPO compare to diesel combustion.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.343-344
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• 2014

Ethanol as fuel of Spark Ignition Direct Injection (SIDI) engine has become a feasible alternative due to its better anti-knock characteristics and lower nano-particle emission level. There are a number of studies on the emission characteristics from SIDI engine fuelled with various ethanol contents. In general, increase of ethanol contents leaded to decrease of nano-particle discharge, but the other researches showed reversed result at a singular range of ethanol contents. This study focused on the engine combustion performance and nano-particle emission characteristics of SIDI engine fuelled with intermediate ethanol contents.

• Tuberculosis and Respiratory Diseases
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• 제40권5호
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• pp.495-500
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• 1993

연구배경 : 수술이 불가능한 주기도의 종양성 병변에 의한 기도 폐쇄를 치료하는 방법으로서 Yag-laser 치료, 체외부 방사선치료나 기관지내 방사선치료법 등이 있다. 최근 조기 간암 환자들에서 직접 ethanol을 암조직내로 투입해서 좋은 효과가 보고되고 있어 저자들도 주기도 폐쇄를 일으킨 폐암환자 11명을 대상으로 기관지경을 통해 직접 암종괴내로 ethanol을 주입하여 기도폐쇄를 호전시킬 수 있었기에 보고하는 바이다. 방법 : 지속적인 산소 주입하에 굴곡성 기관지 내시경을 통해 경기관지 흡입침을 이용하여 종양내로 직접 ethanol을 0.5~1.0ml씩을 수회 주입한 후 생검 겸자로 종양을 제거하였으며 필요시는 3~4일후 이 조작을 되풀이하였다. 결과 : ethanol 주입 직후 점막이 창백해지고 출혈이 즉시 멎었으며 지연 효과로서 종양의 괴사가 발생하였으며, 대부분의 환자에서 2~3회 치료후 기간지가 개방되었고 증상 및 흉부 X-선 사진의 호전을 보였다. 11명 환자들에서 폐기능 검사상 FVC가 $2.1{\pm}0.84L$에서 $2.44{\pm}0.92L$로 $FEV_{1.0}$이 $1.48{\pm}0.69L$에서 $1.80{\pm}0.64L$로 증가하였고, $PaO_2$는 $68.1{\pm}9.2$ mmHg에서 $83.9{\pm}8.1$ mmHg로 (p<0.005), $SaO_2$는 $94{\pm}8.5%$에서 $96.6{\pm}1.1%$(p<0.005)로 증가하였으며, $AaDO_2$는 $26.5{\pm}8.5$mmHg에서 $10.9{\pm}9.1$mmHg(p<0.005)로 감소하였다. 결론 : 종양에 의한 주기관지 폐색환자에서 ethanol을 종양 조직내 직접 주입하는 것은 주기도 폐쇄를 치료하는데 빠른 효과를 볼 수 있으며, 저렴한 비용으로 비교적 안전하게 시행할 수 있는 방법이라 생각한다.