• Applied Chemistry for Engineering
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• v.9 no.6
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• pp.924-929
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• 1998

In this work, high pressure binary phase equilibria data of carbon dioxide with acetonitrile and acrylonitrile were obtained experimentally. A new static type experimental apparatus was built to measure temperature, pressure and phase equilibria composition. The accuracy of the experimental apparatus was tested by comparing the measured phase equilibria data of the carbon dioxide-acetonitrile system at $75^{\circ}C$ with those of McHugh and coworkers. The binary phase behavior data of carbon dioxide-acetonitirle system were measured from 2.4 to 14.5 MPa at $55^{\circ}C$, $75^{\circ}C$ and $100^{\circ}C$. Also, the phase equilibria of the system carbon dioxide-acrylonitrile were measured from 1.6 MPa up to 13.9 MPa at $45^{\circ}C$, $65^{\circ}C$, $85^{\circ}C$ and $105^{\circ}C$. The solubility of acetonitrile and acrylonitrile increases as the temperatures increases at constant pressure. Also, these two carbon dioxide-polar solute system have continuous critical-mixture curves that exhibit maximums in pressure at temperatures between the critical temperatures of carbon dioxide and acetonitrile or acrylonitrile. The experimental data obtained in this study were modeled using the Peng-Robinson equation of state. Good agreement between calculated and experimental results was observed.

• Analytical Science and Technology
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• v.6 no.4
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• pp.383-390
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• 1993

Retention behaviors of aliphatic and aromatic compounds were investigated with Van der Waals volume which represented the molecular size. The organic solvents, methanol, acetonitrile and tetrahydrofuran, were mixed with water at various ratio, respectively. The selectivity of organic solvents were tested by change of column temperature. The capacity factor was increased linearly according to the enlargement of molecular size. Therefore, Van der Waals volume was useful to predict the elution of organic molecules in reversed-phase column. The order of elution capacity of solvents was methanol

• Journal of the Korean Chemical Society
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• v.32 no.1
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• pp.15-21
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• 1988

The Polarographic behavior of 1-(2-thiazolylazo)-2-naphthol (TAN) in acetonitrile solution was studied. From the DC polarograms of TAN in acetonitrile solution, the type of reduction current and the effect of proton donor such as water have been investigated. In order to explain the reduction mechanism, the number of the electrons for each reduction step was measured by controlled potential coulometric technique and the electrolysis products were identified by UV-Vis spectroscopy and IR spectroscopy. The results were shown that the reduction of TAN in acetonitrile solution occurred with four-one electron steps. In addition, each reduction step was considerably reversible and the reduction current was diffusion controlled.

• Korean Journal of Agricultural Science
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• v.11 no.2
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• pp.315-321
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• 1984

The electrochemical reduction of 0,0-dimethyl-0-(3-methyl-4 -nitrophenyl)-phosphorothioate ($Sumithion^{(R)}$) in acetonitrile solution has been studied by direct current (DC), differential pulse (DP) polarography and cyclic voltammetry methods. The irreversible electron-transfer chemical reaction (EC) mechanism of Sumithion proceeds by six electron-transfer to form radical and reduction of three-step which undergoes single bond of the phosphorus atom & phenoxy group by electron-transfer and protonation cleaved to give p-hydroxyamino-m-cresol and dimethylthiophosphonate as major product.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1465-1469
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• 2001

A sensitive high-performance liquid chromatographic method was developed to determine the content of cholesterol in milk and dairy products. To optimize separation of cholesterol, mobile phases including acetonitrile:2-propanol (8:1, v/v), acetonitrile:methanol (3:1, v/v), and acetonitrile:methanoI:2-propanol (7:3: I, v/v/v) were compared. Acetonitrile/methanol/2-propanol was superior to the other mobile phase systems for separating cholesterol. Liquid-liquid extraction (LLE) of cholesterol was simplified using a non-polar solvent, hexane, to remove interfering compounds, and had an excellent recovery $(100{\pm}1.0%)$ of cholesterol. A solid phase extraction (SPE) method using Sep-pak $C_{18}$ was developed and compared with LLE. The SPE method was rapid and highly reproducible. Both extraction methods were useful when used in combination with saponification of esterified cholesterol to facilitate total cholesterol determination. The detection limit of cholesterol was $0.01{\mu}g$. The newly developed HPLC method was rapid, simple, and accurate, and has advantages over the many methods commonly used.

• Analytical Science and Technology
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• v.8 no.4
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• pp.511-517
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• 1995

A cationic water soluble porphyrin (5,10,15,20-tetrakis (l-methyl-pyridinium-4-yl)porphyrin, $H_2tmpyp^{4+}$) and its metalloporphyrins (MP) were easily extracted into acetonitrile separated by addition of sodium chloride ($4mol\;dm^{-3}$) in the presence of sodium perchlorate, where M denotes $Zn^{2+}$, $Cu^{2+}$, $Co^{3+}$, $Fe^{3+}$, and $Mn^{3+}$ and $P^{2-}$ is porphyrinate ion. The extracted ion-pair complexes were completely dissociated to $[MP(ClO_4)_3]^+$, and $[MP(ClO_4)_2]^{2+}$. The extraction and the dissociation constants were determined by taking into account of the partition constant of sodium perchlorate ($K_D=1.82{\pm}0.01$). The chemical properties of the separated acetonitrile phase as $E_{T(30)}$ and $D_{II,I}$ were determined and compared with other water miscible solvents (acetone, actonitrile, 1,4-dioxane, tetrahydrofuran, 1-propanol and 2-propanol). Furthermore, a sensitive and selective method was proposed for the determination of a subnanogram amount of copper(II) in natural water samples by using the present salting-out method and the porphyrins.

• Journal of the Korean Chemical Society
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• v.38 no.3
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• pp.179-185
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• 1994

The Raman stretching frequency of nitrile group was affected by change of solvents and its in concentration in same solvent. In the case of acetonitrile, nitrile group stretching frequencies were observed in the region of 2247.3∼2254.9 cm-1 with various solvents. While in benzonitrile, they were found in the region of 2226.1∼2230.3$ cm^{-1}. With the addition of water in acetonitrile,νC≡N was shifted to high frequency from 2250.1 cm^{-1} in pure acetonitrile to 2257.7 cm^{-1} in 90% water forwhich had with higher volume % of water caused higher hydrogen-bonded equilibrium between methyl protons and water. The νC≡N frequency for nitrile group was shifted to high frequency by solvent inductive effect with the increasing mixed solvent (CHCl_3/CCl_4)$mole% ratio.

• Journal of the Korean Chemical Society
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• v.37 no.10
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• pp.888-894
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• 1993

The electrochemical behaviors of copper-1-(2-pyridylazo)-2-naphthol(Cu-PAN) complex in acetonitrile (AN) solution have been investigated by the use of cyclic voltammetry, DC-polarography, controlled potential coulometry and UV-Vis spectroscopy. Cu-PAN complex in acetonitrile exhibit three reduction waves at -1.27 V, -1.64 V and -2.08 V vs. Ag/AgNO$_3$(AN). The numbers of electron involved in each reduction step was calculated with controlled potential coulometry, and reduction product was identified with UV-Vis spectrum. As the result, we proposed the reduction mechanism of the Cu-PAN complex in acetonitrile.

• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.249-259
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• 1988

The solvent effects of MeOH-solvent dimers were studied via AM1 Hamiltonian and supermolecule methods. Methanol, ethanol, acetone, dimethylsulfoxide, N,N-dimethylformamide, tetrahydrofuran, dioxane, and acetonitrile were considered as solvent molecules. Optimized geometries, electron densities, molecular energies, and hydrogen-bonding energies of monomers and dimers were calculated. We found that the stabilization energies contributed to the hydrogen-bonding were decreased in the order of dimethylsulfoxide > ethanol > N,N-dimethylformamide > acetone > methanol > tatrahydrofuran > dioxane > acetonitrile, and this order was explained by using the change of electron density and energy partition functions.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.436-439
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• 2022

𝛽-Hydroxynitrile and 𝛽-ketonitrile were synthesized by the electrochemical oxidation of benzyl alcohol in an acetonitrile solvent. 𝛽-Hydroxynitrile was prepared by the reaction between benzaldehyde from the oxidation of benzyl alcohol and acetonitrile anion which was produced from the electrochemical reduction of acetonitrile. 𝛽-Hydroxynitrile was finally electrochemically converted into 𝛽-ketonitrile by applying 20 mA of current for 3 h. We demonstrated that 𝛽-hydroxynitrile or 𝛽-ketonitrile syntheses were prepared by electrochemical oxidation of benzyl alcohol with a commonly used Pt electrode at room temperature.