• Journal of the East Asian Society of Dietary Life
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• v.12 no.6
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• pp.566-573
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• 2002

In order to obtain the basic data fer the processing adaptability of Korean figs(Ficus carica L.), physicochemical analyses were carried out with Korean common type figs in the different ripening stages. Moisture contents decreased, but the contents of protein, fat carbohydrate and soluble solids increased according to the ripening of fruits. K was detected as the most abundant one of all the minerals and Ca, Mg, Na, Fe, Mn, Zn and Cu were the next in order. The mineral contents decreased slightly with ripening. Especially, Ca, Mg, U, Fe and Zn were higher in the unripened H stage figs. The antioxidative activity was assayed with water and methanol extracts from ripened figs by the DPPH radical scavenging ability. The antioxidative activities of Korean figs were relatively high and increased in a dose dependent manner. The methanol extract showed the higher antioxidative activity than the water one. Therefore, the methanol was the better solvent than water for the antioxidative compounds. These results suggested that Korean figs are relatively the good sources of minerals, especially the Ca and the antioxidative compounds.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.500-506
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• 1996

To study antimicrobial activities of Impatiens balsamina, its leaf and stem was extracted by methanol and water. The extracts were tested their microbial inhibition activities against several microorganisms, staphylococcus aureus KCTC 1928, Escherichia coli KCTC 1116, Klebsiella pneumoniae KCTC 2690, Trichophyton mentagrophytes KCTC 6316. The methanol extract and water extract of the leaf and stem didn't show the inhibition effect on E. coli but showed the inhibition effect against the ohter 3 species of the microorganisms tested. The extract of leaf showed higher inhibition than the extract of stem. And the methanol extract showed higher inhibition than the water extract.

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1483-1486
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• 1999

The contents of pentachlorophenol (PCP) and 2,3,5,6-tetrachlorophenol (TeCP) in textile products are regulated for safety. Since an organic solvent such as 2-methoxyethanol is needed to extract chlorinated phenols from textile samples, nonaqueous capillary electrophoresis has been applied to achieve the separation of PCP and isomers of TeCP. The run buffer was 100 mM Tris/acetate in methanol whose pH was adjusted to 8.0. All of the analytes were negatively charged at pH 8.0 and their electrophoretic velocities were higher than the electroosmotic flow of the methanol buffer. A reverse voltage of -20 kV was applied along a 27-cm fused silica capillary with ID of 50 μm, and PCP and 3 TeCP isomers were separated based on the difference in $pK_a$ values in less than 4 min. The limits of detection (S/N = 3) were about 0.02 μM. By varying pH of the methanol run buffer, $pK_a$ values of the 4 chlorinated phenols were also estimated.

• Journal of Pharmaceutical Investigation
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• v.10 no.3
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• pp.14-19
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• 1980

The dissociation constant of erythrosine in the mixed solvent systems of water-alcohols and water-acetone at various pH and in concentration media were determined by spectrophotometric method. Methanol, ethanol, and acetone were employed as solvents and studied the changes of pK values of erythrosine according to the kind and change of concentration of organic solvent which is mixed into water solution. The effect of organic solvent on pK is negligible at 40% while in the case of above 40% mixing, it is not negligible.

• Journal of Photoscience
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• v.1 no.1
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• pp.15-23
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• 1994

The absorption and fluorescence spectral properties of piroxicam (PRX) in the hydrogenbonding solvents show the most sensitive dependence on the concentration ranging from 8 x 10$^{_5}$ to 2 x10$^{_5}$ M. These are attributed to both the solvent-mediated ground-state intermolecular proton transfer (GSIerPT) leading to formation of the ground state anion and the excited-state intmmolecular proton transfer (ESIraPT). The concentration dependences of the time-resolved emission kinetics at both room temperature and 77 K have also been investigated. It is shown that in the excited state, the ESIraPT of PRX is the dominant process to form a keto tautomer at the high concentration, whereas at the low concentration the excited-state conformational change of the anion is an additional process leading to formation of a zwitterion. The ESI~PT of PRX in the hydrogenbonding solvent is coupled with the ultrafast excited-state solvent reorganization.

• Archives of Pharmacal Research
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• v.18 no.6
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• pp.454-457
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• 1995

To improve the yield of genuine aglycones from glycosides, the conditions of alkaline hydrolysis were investigated, and a modified method was established. The modified method empolyed pyridine as an aprotic solvent. To complete the hydrolysis and obtain 20(S)-protopanaxadiol (1) and 20(S)-protopanaxatriol(2), which are the genuine aglycones of ginsenosides, total ginsenosides were refluxed with sodium methoxide in pyridine. Addition of methanol, a protic polar solvent to the reaction miuxture, led partial hydrolysis yielding a mixture of the genuine prosapogenols. Of the prosapogenols compound 3 and 6 characteristically possessed D-glucopyranosyl moiety attached at the sterically hindered C-20 hydroxyl group. 3 and 6 were not obtaijned by other hydrolysisw methods except by the soil bacterial hydrolysis.

• Journal of the Korean Chemical Society
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• v.21 no.2
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• pp.83-88
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• 1977

Kinetic studies on the rates of reactions of 2, 4-dinitrochlorobenzene with p-toluidine, aniline and p-chloroaniline in $CH_3CH-CH_3OH$ binary solvent mixtures have been carried out. The experimental results have been explained in terms of the specific solvation by alcoholic hydrogen. It has been shown that the bond breaking step is rate determining in the solvent system studied and the energy barrier is getting low as the solvent changes from acetonitrile to methanol.

• Journal of Environmental Impact Assessment
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• v.9 no.1
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• pp.75-86
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• 2000

The purpose of this work was to document the conditions regarding organic solvent exposure to the workers in paint industry. Air concentrations of organic solvents were measured by passive personal samplers and analyzed by a gas chromatography. Urine samples for hippuric test were also taken from 330 workers who have worked at seven domestic factories for more than two years. Amongst 25 organic elements detected in the indoor environment of working places, toluene was the most common element, and methanol showed the highest mean concentration(18.2ppm). A few elements including methylethyl ketone and toluene partially exceeded the Korean Permissible Exposure Limit. A lack of environmental facilities such as exhaust ventilation, automatic cleaning system, and personal safety devices at present work plaus brings about various occupational diseases.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.353-353
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• 2010

Alcohol is a vesatile polar solvent for molecules. As a preparation to deposit large molecules, we studied interaction of solvent molecules on metallic surface. in this work, we report on methanol adsorption on NiAl(110) with scanning tunneling microscopy (STM). These alcohol solvent molecules were deposited by a pulse injection method suitable for deposition of thermally unstable molecules. The injection of liquid alcohol onto the substrate in UHV was performed by using a high-speed solenoid valve with the back-pressure reduced down to 100 Torr. This technique allowed precise control over the amount of dosing of molecules to less than 1 L. Alcohol-induced features, attributed to methoxy, were found on bare NiAl(110) surface.

• Bulletin of the Korean Chemical Society
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• v.21 no.1
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• pp.81-86
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• 2000

In order to obtain detailed information on ground and excited states of curcumin and curcuminoids, as well as to understand the photobiological characteristics of them, their spectral and photophysical behaviors are investigated in various conditions. Various curcuminoids were obtained and their structures were determined by spectroscopic methods. In n-hexane, the absorption and fluorescence spectra of these compounds contain some structure, which disappear in more polar solvent such as methanol. The fluorescence intensities of curcumin and dimethylated curcumin decrease as the concentration of water increases. The intensities also decrease as the solvent varies from neutral to extremely acidic (lower than pH 1.5) or to basic (higher than pH 8.0) condition. These results indicate that the spectral and photophysical properties of both of curcumin and curcuminoids are strongly influenced by solvent, water, and pH.