• Transactions of the Korean hydrogen and new energy society
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• v.27 no.6
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• pp.721-726
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• 2016

Alcohols are particularly attractive as alternative fuels because they are a renewable resource. This paper describes the performance and emission characteristics of ethanol and diesel blended fuels in a compression ignition engine. This experimental results showed that ethanol diesel blended fuels decreased the torque and brake mean effective pressure. And experimental results indicated that using ethanol-diesel blended fuel, smoke, CO and HC emissions decreased as a result of the ethanol addition.

• Journal of ILASS-Korea
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• v.22 no.3
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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.

• Food Science of Animal Resources
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• v.18 no.4
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• pp.348-357
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• 1998

This study was conducted to investigate the effects of mugwort extracts on the blood ethanol concentration and liver function in rats. Sprague-Dawley rats were used, the rats administered with 25% ethanol (5g/kg$.$B.W.) were devided into three groups (CON-E ; 25% ethanol administered to the CON-E) according to the administered ethanol concentration and the levels of administered mugwonts. Mugwont roots extracts were administered via the caudal vein. Ethanol concentration was measured at the time of 0, 1, 2 and 3hr by gas chromatography. GOT(Glutamic Oxaloacetic Transaminase) and GPT(Glutamic Pyruvic Transaminase) were measured at the time of 0 and 5hr. Components of each extracts were analyzed by using high performance liquid chromatography. Cell number, GOT and GPT were investigated by using rat hepatocyte culture. Megwort extracts were added at the levels of 1% or 2%. Hepatocyte culture were into five groups according to the addition levels. The results were summarized as follows ; 1. Catechin contents of 8∼10mg/100g and the contents of (-)-epigallocatechin was high in the water extracts. 2. Ethanol degradation efficiency declines in the following order : MDW-E＞MOH-E＞CON-E. 3. The numbers of rat hepatocytes declines in the following order : 2% MDW-L＞1%MDW-L＞1%MOH-L＞CON-L＞2%MOH-L. These results suggest that crude catechin of mugwort extracts may play important roles to degrade ethanol and recover liver function in rats.

• YAKHAK HOEJI
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• v.40 no.1
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• pp.78-83
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• 1996

An ethanol administration causes hepatic triglyceride accumulation in rats. To assess whether the herbal extract containing Phaseoli radiati semen(herbal extract) inhibit s the triglyceride accumulation in the liver, we determined the hepatic triglyceiide levels in rats fed ethanol and the herbal extract. In addition, the blood ethanol concentrations and the activities of hepatic alcohol dehydrogenase(ADH) and aldehyde dehydrogenase(ALDH) were measured to determine the effects of the herbal extract on alcohol metabolism in rats. The administration of the herbal extract markedly reduced the triglyceride levels elevated by ethanol in the liver as well as in the serum. The herbal extract remarkably lowered blood ethanol concentrations in a dose-dependent manner. The ADH activities decreased by ethanol were recovered to the normal level by the herbal extract treatment. Moreover, the ALDH activities slightly decreased by ethanol increased beyond the normal level by the herbal extract treatment. We conclude that the herbal extract inhibits the hepatic triglyceride accumulation and stimulates alcohol metabolism by preventing ADH and ALDH from inhbition by the ethanol administration in the rat liver.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.1-8
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• 1996

A one-stage, continuous-flow bioreactor with both immobilized and suspended cells was used to investigate the roles of lipid supplements in ethanol production by Saccharomyces cerevisiae. The reactor performance and the level of alcohol dehydrogenase(ADH) activities of the suspended cells, grown under various conditions, were measured. When ergosterol and/or oleic acid were added with surfactants to the yeast culture grown under non-aerated conditions, remarkable increases in ethanol production and cell growth was achieved, but specific ADH activities were not affected. Especially, no difference of specific ADH activities of the suspended cells grown under aerated and non-aerated condition was observed. The addition of the surfactant as a supplement also resulted in significant increases in ethanol production, cell growth, and specific ADH activity. When ergosterol and oleic acid were added to the yeast culture exposed to higher ethanol concentration($>40\;g/{\ell}$) level, ethanol production, cell growth, and specific ADH activity were increased, but the addition of surfactant was as effective as at lower ethanol concentration level. The results indicated that lipid supplements were more effective at higher ethanol concentration level than at lower ethanol concentration level during ethanol production. ADH isozyme patterns of the yeast cultures grown under various conditions on starch gel electrophoresis showed only one major band, probably ADH I. The migrating distance of the major isozyme, however, varied slightly according to the culture conditions of the cells. No apparent correlation was found between specific ADH activity and amount of ethanol produced. Cell mass was more important factor for ethanol production than specific ADH activity of the cells.

• Food Science of Animal Resources
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• v.35 no.2
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• pp.265-271
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• 2015

In a previous study, hydrolysates of porcine placenta were obtained and the extraction efficiency for proteins and amino acids was compared between sub- and super-critical water extraction systems; optimum efficiency was found to be achieved using subcritical water ($170^{\circ}C$, 10 bar). In this study, the effects of adding ethanol to the subcritical water system were investigated. The lowest-molecular-weight extraction product detected weighed 434 Da, and the efficiency of extraction for low-molecular-weight products was increased when either the concentration of ethanol was decreased, or the extraction time was lengthened from 10 min to 30 min. The highest concentration of free amino acids (approximately 8 mM) was observed following 30 min extraction using pure distilled water. The concentration of free amino acids was significantly lower when ethanol was added or a shorter extraction time was used (p<0.05). Color change of the solution following extraction was measured. There were no significant differences in color between lysates produced with different extraction times when using distilled water (p>0.05); however, using different extraction times produced significant differences in color when using 20% or 50% ethanol solution for subcritical extraction (p<0.05). The range of pH for the hydrolysate solutions was 6.4-7.5. In conclusion, the investigated extraction system was successful in the extraction of $\leq$ 500 Da hydrolysates from porcine placenta, but addition of ethanol did not yield higher production of low-molecular-weight hydrolysates than that achieved by DW alone.

• KSBB Journal
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• v.4 no.2
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• pp.172-176
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• 1989

The alcohol fermentation was carried out to study the effect of aeration and unsaturated fatty acids added on the ethanol tolerance of Saccharomyces cerevisiae STV89 and Kluyveromyces fragilis CBS397. The cell growth rate and ethanol production rate was stimulated by aeration and the cell mass production and ethanol production were also substantially improved. With respect to strains, the maximum specific growth rate and overall ethanol productivity of K. fragilis under aerated condition were 6.4 fold and 4.4 fold higher than those of strictly anaerobic condition, although those of S. cerevisiae were increased 1.7 times and 2.3 times by aeration. The addition of ergosterol, linoleic acid and oleic acid also improved the cell growth and ethanol production of S. cerevisiae and K. fragilis. Thus it was found that oxygen and unsaturated fatty acids added played a decisive role on the increase of ethanol tolerance of yeast strains.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.264-264
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• 2012

As an environment-friendly alternative energy resource, ethanol may be used to obtain hydrogen, a clean energy source. Thus, studies on catalytic reactions involving ethanol have been studied to understand the underlying principles in the reaction mechanism using various oxide-supported catalysts. Among them, Au-based catalysts have shown a superior activity in producing hydrogen gas. In the present study, Au/$TiO_2$ catalysts were prepared by deposition-precipitation method to understand their catalytic activities toward ethanol and acetaldehyde with increasing gold loading, especially at the very low Au loading regime. A commercially available $TiO_2$ (Degussa P-25) was employed and the Au loading was varied to 0, 0.1, 0.5, and 1.0 wt% respectively. The catalysts showed characteristic x-ray diffraction (XRD) features at $2{\theta}=78.5^{\circ}$ that could be assigned to the presence of gold nanoparticles. Its reactivity measurements were performed under a constant flow of ethanol and acetaldehyde at a flow rate of ${\sim}0.6{\mu}mol/sec$ and the substrate temperature was slowly raised at a rate of 0.2 K/sec. We observed that the overall reactivity of the catalysts increased with increasing Au loading along with selectivity favoring dehydrogenation to product hydrogen gas. In addition, we disclosed various reaction channels involving competitive reaction paths such as dehydrogenation, dehydration, and condensation. In addition, subsequent reactions of acetaldehyde obtained from dehydrogenation of ethanol, were found to occur and produce butene, crotonaldehyde, furan, and benzene. Based on the results, we proposed overall reaction pathways of such reaction channels.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1158-1163
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• 2001

This study was carried out to investigate the effect of ethanol extract of Pinus densiflora (PD) on the growth of lactic acid bacteria (LAB), A-1, B-9, K-7, M-7 isolated from kimchi. The growth of isolated LAB was inhibited significantly in the modified MRS broth containing 40 mg/mL PD ethanol extract. Ethyl acetate fraction showed the strongest antimicrobial activities against LAB strains compared to other fractions. The addition of PD ethanol extract to kimchi did not change the pH of kimchi greatly compare with the control during the fermentation for 25 days. Change of titratable acidity in control was more higher than in the PD ethanol extract added kimchi during fermentation. The growth of total bacteria and LAB was inhibited about 1 to 2 log cycle by the addition of PD ethanol extract during the kimchi fermentation for 25 days at 1$0^{\circ}C$. Sensory quality of PD ethanol extract added kimchi was lower than that of control.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.237-242
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• 2022

In this study, a drying method that can effectively remove residual solvent from (+)-dihydromyricetin was developed. Residual acetone concentration was efficiently removed below ICH-specified value (5,000 ppm) by simple rotary evaporation with ethanol pretreatment. In addition, the residual ethanol met the ICH-specified value (5,000 ppm) by simple rotary evaporation through the addition of water, and the residual moisture also met the specified value (<4%) for active pharmaceutical ingredients. At all the drying temperature (35, 45, and 55 ℃), a large amount of the residual solvent was initially removed during the drying, and the drying efficiency increased when increasing the drying temperature. Removal of residual solvent by ethanol pretreatment was shown to be related to high vapor pressure of acetone-ethanol mixture and hydrogen bonding between acetone and ethanol.