• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.738-742
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• 2003

In order to estimate the mass transfer characteristics of absorption into alcohol solution of aroma compounds such as cineol, myrecene and pinene which are major aroma compounds of rosemary, dimensionless Henry's constant in 70% ethyl alcohol concentration and aroma concentration with different ethyl alcohol concentration were analyzed. From the results of measurement of vapor phase concentration of aroma compounds with different ethyl alcohol concentration, headspace concentrations of all of three aroma compounds were decreased as ethyl alcohol concentration increased. But those patterns were slightly different. Dimensionless Henry's constant equation (Hi) of cineol compound with ethyl alcohol concentration (x) was as follows: $Hi=(-5.75+x)/(-7017.6+257.3{\times}x)$. Dimensionless Henry's constants of cineol, myrecene and pinene in 1 atm, $25^{\circ}C$ and 70% ethyl alcohol concentration were 0.0058, 0.0182 and 0.0365, respectively.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.233-239
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• 2013

A quartz crystal microbalance (QCM) system coated with poly (isobutylene), polystyrene, and poly (methyl methacrylate) has been prepared to measure the adsorption amounts of benzene, toluene, and p-xylene at very low pressures. The resonant frequency shift of the QCM system is proportional to the increase in pressure in all experiments. The Henry's constants for all adsorbates on the polymer films are obtained from experimental data and compared with the minimum adsorption potential energies between adsorbates and the polymer films. In general, there is an explicit correlation between adsorption amount and the minimum adsorption potential energy.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.9
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• pp.165-171
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• 1999

An oil layer fuel absorption /desorption modeling was developed. Multi-component fuel model has showed more reasonable condition than single component model. Henry's constant which is related to solubility is the most important variable in the oil layer absorption/desorption mechanism. The oil segments close to the top of the cylinder liner have more significant contribution to the fuel absorption and desorption process than other oil segments. At the warmed-up condition, the effect of the engine speed on the precent fuel absorbed/desorbed is minimal. But at low il film temperature, percent of fuel abosrbed/desorbed is decreased with increasing the engine speed because of low value of molecular diffusion coefficient of fuel. The amount of fuel trapped in the piston crevice is from 2 to 2.3 times larger than that of fuel in the oil fim. However, fuel form oil film slowly desorbs into the combustion chamber compared with fuel from the piston crevices when the engines is cold.

• Journal of the Korean Chemical Society
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• v.26 no.4
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• pp.211-217
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• 1982

Assuming krypton molecules adsorbed on the graphite surface as a two-dimensional (2D) gas, 4th virial coefficient of the virial equation is calculated by the use of cluster integrals. The Henry's law constant, and 2nd and 3rd virial coefficients are also calculated. Adsorption isotherms calculated from this virial equation agree very satisfactorily with experimental results. The interaction energy of Kr-graphite surface is calculated assuming the pairwise additivity of Lennard-Jones(12,6) potential, and parametars therein are taken as; ${\varepsilon}_{gs}$/k = 71.1 K, ${\varepsilon}_{gg}$/k = 170 K, ${\sigma}_{gs}$ = 354 pm, and ${\sigma}_{gg}$ = 368 pm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.136-152
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• 2017

The thermodynamic models, PC-SAFT (Perturbed-Chain Statistical Associated Fluid Theory) state equation and the Two-model approach liquid activity coefficient model NRTL (Non Random Two Liquid) + Henry + Peng-Robinson, for modeling the Rectisol process using methanol aqueous solution as the $CO_2$ removal solvent were compared. In addition, to determine the new binary interaction parameters of the PC-SAFT state equations and the Henry's constant of the two-model approach, absorption equilibrium experiments between carbon dioxide and methanol at 273.25K and 262.35K were carried out and regression analysis was performed. The accuracy of the newly determined parameters was verified through the regression results of the experimental data. These model equations and validated parameters were used to model the carbon dioxide removal process. In the case of using the two-model approach, the methanol solvent flow rate required to remove 99.00% of $CO_2$ was estimated to be approximately 43.72% higher, the cooling water consumption in the distillation tower was 39.22% higher, and the steam consumption was 43.09% higher than that using PC-SAFT EOS. In conclusion, the Rectisol process operating under high pressure was designed to be larger than that using the PC-SAFT state equation when modeled using the liquid activity coefficient model equation with Henry's relation. For this reason, if the quantity of low-solubility gas components dissolved in a liquid at a constant temperature is proportional to the partial pressure of the gas phase, the carbon dioxide with high solubility in methanol does not predict the absorption characteristics between methanol and carbon dioxide.

• Journal of the Korean Chemical Society
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• v.25 no.4
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• pp.246-252
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• 1981

Assuming krypton molecules adsorbed on graphite surface as 2D gas, the interaction energy of Kr-graphite and the Henry's constant are calculated analytically by the Fourier series expansion method. 2D virial cofficients, $B_{2D}$ and $C_{2D}$, are also calculated to obtain 2D equation of state, and hence adsorption isotherms. The isotherms so obtained are compared with experimental results reported by Putnam and Fort. The pairwise additivity of Lennard-Jones(12, 6) interaction energy is also assumed, and parameters therein are taken as; ${\varepsilon}_{gs}$/k = 70 K, ${\sigma}_{gs}$ = 0.35 nm, ${\varepsilon}_{gg}$/k = 170 K, and ${\sigma}_{gg}$ = 0.37 nm.

• Applied Chemistry for Engineering
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• v.10 no.1
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• pp.129-134
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• 1999

This study is related to the investigation of the direct incorporation of $CO_2$ to polymer using quaternary ammonium salt catalysts. Quaternary ammonium salts showed good catalytic activity of $CO_2$ fixation in the synthesis of poly[(1,3-dioxolane-2-oxo-4-yl)methyl methacrylate] [poly(DOMA)] by the direct incorporation of $CO_2$ to poly(glycidyl methacrylate)[poly(GMA)]. Among the salts tested, the ones with higher alkyl chain length and with more nucleophilic counter anion showed higher catalytic activity. The yield of carbon dioxide addition increased with the reaction temperature. Kinetic study was carried out by measuring the variation of $CO_2$, pressure in a high pressure batch reactor. The reaction rate was first order to the concentration of poly(GMA) and $CO_2$, respectively. The rate constant was $0.69L/mol{\cdot}h$ and Henry's constant of $CO_2$ in DMSO at $80^{\circ}C$ was $6.8{\times}10^{-4}mol/L{\cdot}KPa$.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1156-1163
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• 1996

This study is related to the investigation of the characteristics of quaternary ammonium salt catalyst on the addition reaction of carbon dioxide and glycidyl methacrylate(GMA) to form(2-oxo-1,3-dioxolane-4-yl)methacrylate(DOMA). Among the salts tested, the ones with higher alkyl chain length and with more nucleophilic counter anion showed a higher catalytic activity. Mixed catalysts of NaI and 18-crown-6 showed a good yield of DOMA, but when they are used alone, they showed no catalytic activity. The DOMA monomer was obtained in low polar solvents, while poly(DOMA) could be directly synthesized in aprotic dipolar solvents. Kinetic studies carried out by measuring $CO_2$ pressure in a high pressure batch reactor showed that the reaction rate was first order to the concentration of GMA and $CO_2$ respectively. The rate constant(k) was 0.56L/mol hr and Henry's constant(H') of $CO_2$ in diglyme at $80^{\circ}C$ was $6.5{\times}10^{-4}mol/L{\cdot}kPa$.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.21-31
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• 2000

Performance characteristics of a wet air cleaning system were investigated experimentally, and discussed in relation with physicochemical properties of the target pollutants. The system is composed of an air cleaner, a separator, and a medium filter. Removal efficiency of the system was measured for ambient particles and gaseous air pollutants: $SO_2$, NO, $NO_2$, HCHO, and $NH_3$. For particle removal test, particles were introduced into the system through a fan, and the particle size distribution was measured at three locations by using two laser particle counters. Particle removal efficiency for each system component was obtained from the particle size distribution. It was found that the separator primarily removed coarse particles greater than $5{\mu}m$ in diameter, and that the medium filter mainly removed fine particles less than $5{\mu}m$ in diameter. For gas removal test, air with gaseous air pollutant was injected into the outlet of the fan, and the concentration was measured both at the upstream of the air cleaner and at the downstream of the separator. It was found that the gaseous species with high Henry's law coefficients, such as $SO_2$, HCHO, and $NH_3$, showed high removal efficiency, but the gaseous species with low Henry's law coefficients, such as NO and $NO_2$, showed low removal efficiencies. It was also found that negative ions were generated from the air cleaner.

• Journal of the Korean Electrochemical Society
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• v.2 no.3
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• pp.163-170
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• 1999

The effects of the operating conditions in AFC single cells have not been studied in detail. In this study, by using a one-dimensional isothermal model a computational simulation was conducted to investigate the effects of the initial electrolyte concentration and the operating gas pressure. According to the result, the optimum electrolyte concentration at the base-case was found to be within $3.0\~3.5$ M. The variation of the cell performance according to the electrolyte concentration was found to be caused mainly by the charge transfer resistances of both electrodes, Henry's constant and the liquid phase diffusivity of the dissolved gases. It was also found that an increase in operating pressure increased the reaction rates and the solubilities of the gases, which led to a considerable enhancement of the cell performance.