• Applied Biological Chemistry
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• v.32 no.2
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• pp.143-147
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• 1989

The volatile compounds of McIntosh apples were separated and identified at the stage of climacteric maximum. 21 compounds were identified from head space method and classes of that were 13 kinds of esters, 6 of alcohols, an aldehyde and a ketone. From simultaneous steam distillation-extraction method, 37 compounds were identified and classes of that were 20 kinds of esters, 14 of alcohols, 2 of aldehydes and a ketone. Esters were the most abundant flavor component in the both methods and next was alcohols.

• Membrane Journal
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• v.13 no.1
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• pp.47-53
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• 2003

Poly(ether ether ketone)(PEEK) was sulfonated using sulfuric acid and blended with polysulfone with various ratios. The blended polymer electrolyte membranes were characterized in terms of methanol permeability, proton conductivity and ion exchange capacity. As the amount of sulfonated PEEK increased, both methanol permeability and proton conductivity increased. This was due to the increase of ion exchange capacity. The experimental results indicated that the blend membrane with 20% polysulfone was the best choice In terms of the ratio of proton conductivity to methanol permeability.

• Bulletin of the Korean Chemical Society
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• v.26 no.1
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• pp.97-102
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• 2005

The addition reactions of $\alpha$,$\alpha$-difluoroiodomethyl n-butyl ketone, α,α-difluoroiodomethyl cyclohexyl ketone, or $\alpha$,$\alpha$-difluoroiodomethyl phenyl ketone to alkenes were successfully accomplished in good yields in the presence of copper powder. The reaction was also applicable to alkenes containing a variety of functional groups such as ester, trimethylsilyl, or ether group. Acetonitrile was determined to be the best solvent in the present study and the reaction was performed at 55 ${^{\circ}C}$ for 15-22 h. This reaction provides a new, efficient and general method for the synthesis of $\alpha$,$\alpha$-difluoro functionalized ketones.

• Journal of the Korean Society of Tobacco Science
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• v.26 no.2 s.52
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• pp.109-116
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• 2004

This study was conducted to investigate the composition of flavor components of Elsholtzia ciliata and Eisholtzia splendens in order to obtain basic informations for the application of tobacco and food industry. Flavor components extracted were divided into three fractions ; essential oil, absolute and oleoresin from E. ciliata and E. splendens. Essential oil was extracted by simultaneous steam distillation(SDE), absolute and oleoresin were extracted by $100\%$ n-hexane and $50\%$ ethanol, respectively. Yields of the essential oil, absolute and oleoresin fractions from E. ciliata were $0.34\%,\;11.34\%\;and\;15.24\%,$ and those from E. splendends were $0.28\%,\;12.45\%\;and\;9.95\%$, respectively. The major components of essential oil of E. ciliata were naginata ketone$(29.37\%)$, elsholtzia ketone$(14.37\%)$ and rosefuran$(11.76\%)$. The major components of essential oil of E. splendens were 2-cyclohexen-1-one$(26.81\%)$, elsholtzia ketone$(13.46\%)$ and naginata ketone$(5.26\%).$ The composition of flavor components showed a slight difference between essential oils of E. ciliata and E. splendens. The major components of absolute fraction from E. ciliata were linoleic acid$(12.07\%),$ palmitic acid$(10.46\%)$ and 2-cyclohexene-1-one$(5.39\%).$ And those from E. splendens were linoleic acid$(12.38\%),$ palmitic acid$(9.47\%)$ and naginata ketone$(8.86\%).$ Ethyl linoleolate was a major component in oleoresin of E. ciliata and E. splendens.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.708-715
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• 2016

The modelling and optimization of Methyl Ethyl Ketone (MEK)-Cyclohexane (CH) separation process were performed using pressure-swing distillation with a low-high pressure column and a high-low pressure column configuration. The optimization was performed for the number of theoretical stages, and the location of the feed tray of low column and high column to obtain high-purity MEK at the top. The total reboiler heat duty at the low-high pressure column configuration and high-low pressure column configuration were at 11.7667 Mkcal/h and at 10.3484 Mkcal/h, respectively. The results showed that total reboiler heat duty could be reduced to 12.05% using a high-low pressure column configuration.

• Membrane Journal
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• v.26 no.1
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• pp.62-69
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• 2016

In this study, sulfonated poly(ether ether ketone) (SPEEK) as cation exchange membrane and blended and crosslinked poly(vinyl amine) (PVAm) with poly(vinyl alcohol) (PVA) membrane as anion exchange membrane were used and then the performance experiments of the membrane capacitive deionization (MCDI) installed with both membranes were carried out. The newly prepared anion exchange membrane were characterized through water content, ion exchange capacity and FT-IR. The crosslinking time of 3 h to 5 h indicated that the salt removal was reduced from 81.3, 65.7% to 53.8%. The effect of PVAm contents from 40, 60, to 80% on the salt removal was shown 81.3, 75.2 and 37.7%, respectively. As a result, it was concluded that the crosslinking time and the content of PVAm had an influence on the salt removal efficiency.

• Applied Chemistry for Engineering
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• v.24 no.3
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• pp.247-252
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• 2013

Sulfonated poly(ether ether ketone) (SPEEK) with a certain degree of sulfonation were synthesized by reacting PEEK and sulfuric acid at different reaction time. Then ion-selective composite carbon electrodes (ISCCE) were fabricated by coating the prepared SPEEK on the surface of carbon electrodes. The specific capacitance and resistance of the ISCCE were analyzed by electrical impedance spectroscopy. The ion exchange capacities (IEC) of the SPEEKs were measured in the range of 1.60~2.57 meq/g depending on the sulfonation time. The SPEEK more than 2.5 meq/g of IEC was considered unsuitable for fabricating the ISCCE because it was dissolved in water. The specific capacitance of the prepared ISCCE increased with increasing the IEC of coated SPEEKs and the capacitance was improved up to about 20% compared to that of uncoated carbon electrode. In addition, the electrical resistance of coating layer decreased significantly with increasing the IEC of coated SPEEKs. It is expected that the desalination efficiency of conventional capacitive deionization process can be improved by using the prepared ISCCE coated with SPEEK.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.339-343
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• 2012

Poly(olefin ketone) terpolymer having excellent mechanical properties was synthesized and composite materials of poly(olefin ketone) containing polyurethane/amino silane functionalized glass fibers were prepared. The compatibilities between the functionalized glass fiber and the polymer were characterized by observing the fracture surfaces of the composites using scanning electron microscopy (SEM). Mechanical properties of composites with different contents, diameters, lengths, and binders of glass fibers were also studied using universal testing machine (UTM). The introduction of suitably functionalized glass fiber into the poly(olefin ketone) produces composite materials having excellent mechanical properties and they are very promising alternative materials for the engineering plastic applications.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1177-1179
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• 1996

A static headspace gas chromatographic (HSGC) technique was used to quantify toluene and other solvents (methanol, isopropyl alcohol, methyl ethyl ketone and ethyl acetate) in food packaging films. Comparison of retention times and coefficient variations for standard solvents showed consistent retention time and good reproducibility. Therefore, this method using static HSGC proved to be superior in rapidity and reproducibility, and is thought to be adaptable to analysis of a large number of samples. The methanol content was $N.D.\;(not\;detected){\sim}0.939\;mg/m^2$, toluene $N.D.{\sim}1.403\;mg/m^2$, melthyl ethyl ketone $N.D.{\sim}0.932\;mg/m^2$, total solvent content was $N.D.{\sim}2.433\;mg/m^2$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3764-3773
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• 2012

In this study, modeling and optimization works were completed for the separation of 99.9 mol% of methyl ethyl ketone from water through a pressure-swing distillation process since the azeotropic composition varies very sensitively with the change of system pressure. PRO/II with PROVISION release 9.1 was used for the computer simulation and Wilson activity coefficient model was chosen as a modeling equation. A pressure-swing distillation process can be classified into a low-high pressure columns configuration and a high-low pressure columns configuration. In this work, each configurations were optimized for the minimization of steam consumptions, respectively and were compared.