• Toxicological Research
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• 제17권1호
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• pp.7-9
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• 2001

The quantitative assessment of the penetration of organic solvents through skin is necessary for the evaluation of health hazards in occupational environments. We investigated the rate of dermal penetration when mixed or single forms of organic solvents were placed into a diffusion cell in vitro or into an experimental animal in vivo. The diffusion rates of methanol. toluene, and styrene were 6.07, 0.129, and 0.046 mg/$cm^2$/h, respectively. When skin was exposed to the mixed solvent of methanol and toluene, the penetration rate of toluene did not change significantly (0.110 mg/$cm^2$/h). However, the rate of methanol penetration increased to 43.90 mg/$\textrm{cm}^2$/h. The penetration rate of methanol also increased significantly to 54.69 mg/$cm^2$/h by mixing it with styrene. The concentration of methanol in the blood was monitored during the epicutaneous exposure in rats. The blood concentration of methanol was increased by mixing methanol with toluene as seen in the in vitro experiments. These results showed that the penetration rate of organic solvents would be enhanced by mixing them with other solvents.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.3-8
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• 2008

Effect of external heating rate on the conversion efficiency for the steam reforming of methanol is investigated numerically considering both heat and mass transfer of the species in a packed bed microreactor. In a results from the numerical simulation, the conversion efficiency of methanol has been obtained for the external heating rate. The axial variation of mole fraction of methanol has been additionally presented for several cases of external heating rates. The results show that for the constant inlet temperature condition the conversion efficiency of methanol increases with external heating rate over the range of operating conditions.

• 미생물학회지
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• 제21권3호
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• pp.163-169
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• 1983

Effects of temperature on the gorwth characteristics and the chemical composition of pseudomonas cells grown under glucose-or methanol-utilizing continuous culture were studied. In a glucose-utilizing continuous culture, optimum dilution rate, agitation, pH, and temperature, for the higher biomass yield were $0.45hr^-$, 7000rpm, pH 7.5, and $30^{\circ}C$, respectively. But in a methanol-utilizing continuous culture, they were $0.125hr^-$, 600rpm, pH 8, and $30^{\circ}C$, respectively. In methanol-utilizing continuous culture, the maximum production rate of the cells was 1.48g, dry wt./1/hr at a dilution rate of $0.45hr^-$, and the cell yield was 0.46g. dry wt./g. glucose. In the methanol-utilizaing continuous culture, the maximum production rate of the cells was 0.33 7g. dry wt./1/hr. at a dilution rate of $0.125hr^-$ and the cell yield was 0.44g dry cell/g. methanol. The contents of protein of the cells increase with the increase ingrowing temperature (from 15 to $30^{\circ}C$), more or less, while the contents of RNA nad carbohydrate of the cells decreased. However, DNA contents of cells growth under the various temperature ranges didn't change. As the temeprature of cultivation rises at a constant dilution rate, the efficiency of RNA in protein synthesis was increased, showing the decreases in the ratio of RNA to protein.

• 한국응용과학기술학회지
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• 제26권4호
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• pp.394-399
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• 2009

The esterification of palmitic acid in Jatropha Oil using 8wt% p-TSA catalyst was done at the 1:8 molar ratio of oil to methanol and $65^{\circ}C$. The conversion of palmitic acid appeared to be 95.3% in 60min. After that, the continuous transesterification of the oil using 0.5wt% KOH, 0.8wt% TMAH mixed catalyst[40vol% KOH(0.5wt%) + 60vol% TMAH(0.8wt%)] and 1.1wt% TMAH was conducted with the flow rates and the molar ratios at $65^{\circ}C$. The overall conversion of Jatropha Oil increased with the decrease of flow rate and showed 95.6% with 9ml/min of flow rate at the 1:8 molar ratio of oil to methanol and $65^{\circ}C$. But it showed 87% with 15ml/min of flow rate at the same conditions. The recovery of methanol(%) appeared to be 86% at the 1:8 molar ratio of oil to methanol, mixed catalyst and $65^{\circ}C$.

• Korean Journal of Chemical Engineering
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• 제35권11호
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• pp.2145-2149
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• 2018

The formation of methanol directly from methane and steam was observed over Cu ion-exchanged mordenite. Furthermore, the continuous production of methanol was achieved by co-feeding methane and steam over Cumordenite. The methanol production rate was comparable to that reported in the stepwise process in which activation, methane reaction, and extraction of methanol were carried out separately.

• 대한화학회지
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• 제29권5호
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• pp.465-471
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• 1985

메탄올-아세토니트릴, 메탄올-아세톤, 에탄올-아세토니트릴 및 에탄올-아세톤의 이성분 혼합용매에서 2-염화 안트라퀴논 카르보닐의 가용매분해반응 속도상수를 전기전도도법으로 측정하였다. 메탄올-아세토니트릴 이성분 혼합용매계에서는 메탄올의 몰분율 $X_{MeOH}$ = 0.73∼0.81에서, 메탄올-아세톤 이성분 혼합용매계에서는 메탄올의 몰분율 $X_{MeOH}$ = 0.83에서 각각 최대 반응속도 현상이 나타났다. Kivinen 관계식과 Grunwald-Winstein 관계식등의 적용으로 부터 본 반응이 $S_N2$형태의 반응메카니즘으로 진행함을 알 수 있었다. Taft의 분광용매화 관계식의 적용으로 부터 메탄올-아세토니트릴 및 메탄올-아세톤 혼합용매계에서는 용매의 수소결합주게효과(${\alpha}$)와 극성-편극성 효과가 중요하게 작용함을 알 수 있었으며, 에탄올의 이성분 혼합용매계에서는 용매의 수소결합주게 효과만 이 반응에 크게 기여함을 알 수 있었다.

• 한국분무공학회지
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• 제4권3호
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• pp.24-31
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• 1999

The engine performance and combustion characteristics of methanol blended fuel of spark ignition engine were discussed on the basics of experimental investigation. The effects of methanol blending fuel on combustion in cylinder were investigated under various conditions of engine cycle and blending fuel on combustion in cylinder were investigated tinder various conditions of engine cycle and blending ratios. The results showed thai the engine performance was influenced by the methanol blending ratio and the variations of operating conditions test engine. The increase of fuel temperature brought on the improvement of combustion characteristics such as cylinder pressure. the rate of pressure rise and heat release in an engine. The burning rate of fuel-air mixture, the exhaust emissions and the other characteristics of performance were discussed also.

• 대한기계학회논문집B
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• 제20권10호
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• pp.3381-3386
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• 1996

The engine performance and combustion characteristics of methanol blended fuel in spark ignition engine were discussed on the basis of experimental investigation. The effects of methanol blending fuel on combustion in cylinder were investigated under various conditions of engine cycle and blending ratio. The results showed that the engine performance was influenced by the methanol blending ratio and the variations of operating conditions of test engine. The increase of fuel temperature brought on the improvement of combustion characteristics such as cylinder pressure, the rate of pressure rise and heat release in an engine. The burning rate of fuel-air mixture, the exhaust emissions and the other characteristics of performance were discussed also.

• Bulletin of the Korean Chemical Society
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• 제6권1호
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• pp.19-23
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• 1985

Solvolysis of 1-adamantyl chloride, -bromide and -tosylate have been studied in methanol-acetonitrile mixtures. Rate maxima were found for 1-adamantyl bromide and tosylate at 80-90 % methanol mixtures. The rate maximum observed was interpreted as a result of cooperative enhancement of cation and anion solvation. 1-Adamantyl tosylate had small cation solvation but had extensive anion solvation. It was concluded that the Y scale based on adamantyl tosylate is superior to others since it varies in a wide range especially for weakly ionizing medium.

• Bulletin of the Korean Chemical Society
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• 제18권9호
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• pp.1017-1021
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• 1997

Solvolyses of p-methoxyphenyl chloroformate in water, D2O, CH3OD, 50% D2O-CH3OD, and in aqueous binary mixtures of acetone, ethanol and methanol are investigated at 25.0 ℃. Product selectivities are reported at 25 ℃ for a wide range of ethanol-water and methanol-water solvent compositions. The Grunwald-Winstein plots of first-order rate constants for p-methoxyphenyl chloroformate with YCl (based on 1-adamantyl chloride) show marked dispersions into three separate curves for the three aqueous mixtures with a small m value and a rate maximum for aqueous alcohol solvents. Third-order rate constants, kww, kaw, kwa and kaa were calculated from the observed kww and kaa values together with kaw and kwa calculated from the intercept and slope of the plot of 1/S vs. [alcohol]/[water]. The calculated rate constants, kcalc and mol % of ester agree satisfactorily with those of the observed rate constants, kobs and mol % of ester, supporting the stoichiometric solvation effect analysis. The kinetic solvent isotope effects determined in water and methanol are consistent with the proposed mechanism of the general base catalyzed carbonyl addition-elimination.