• 대한화학회지
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• 제52권6호
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• pp.668-675
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• 2008

• Natural Product Sciences
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• 제14권3호
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• pp.152-155
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• 2008

An HPLC-ESI-MS method has been developed to identify and quantify two main tetracyclic triterpenes, alisol B 23-acetate and alisol C 23-acetate in the Alismatis Rhizoma (Taeg-Sa). The relative distribution of the two triterpenes in the methanolic extract of commercially available Alismatis Rhizoma was established by selective ion monitoring (SIM) mode via electrospray ionization (ESI) source. Regression equations revealed good linear relationship, and the correlation coefficients were 0.999 and 0.998 for alisol B 23-acetate and alisol C 23-acetate, respectively, between the peak areas of the components and their concentration in a range of $0.06-2.0{\mu}g/mL$. It was found that there were significant differences in the amount of alisol B 23-acetate and alisol C 23-acetate between Korean and Chinese origins. The results showed that this method could be used to identify the two components in Alismatis Rhizoma with high sensitivity and selectivity.

• 기술사
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• 제20권3호
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• pp.26-29
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• 1987

The physical and chemical characteristics of bacteriostatic water filter media are compared to granular activated carbon upon which a silver impregnated. Silver ion that has been chemically impregnated the activated carbon was the bactericidal agent in water filter media. Also, silver Ion that has teen chemically impregnated onto the activated acetate resin was the bactericidal agent in ultrasonic humidifier. Silver impregnated active carbon and silver cartridge will be able to the bactericidal agents for statical water.

• 한국염색가공학회지
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• 제19권4호
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• pp.10-17
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• 2007

Chitosan(CS) and cellulose acetate(CA) composite films were prepared using formic acid as a cosolvent by casting, solvent evaporating and neutralization method. This study examines if the blending method, which uses formic acid as a cosolvent is efficient in improving the mechanical properties of CS film, especially wet strength and elongation. Formic acid is an effective cosolvent for the blend of CS and CA. Under wet condition, tensile strength and elongation of the composite films were obviously higher than those of the films made from pure CS. FTIR, DSC, and X-ray diffraction showed that the composite films exhibit a high level of compatibility and that strong interaction between the CS and CA was caused by intermolecular hydrogen bonding. The affinity series of composite film to transition metal ions are Cu(II) > Cd(II) > Cr(III). The adsorption of Cu((II) ion was shown to be highly pH sensitive.

• 한국응용과학기술학회지
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• 제32권3호
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• pp.363-371
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• 2015

n-Butanol and ethyl acetate extracts of thermal treatment yam (Dioscorea batatas $D_{ECNE.}$) belonging to the family Dioscoreaceae were measured for their radical scavenging activity and lipid peroxidation inhibition ability. In this study, ethyl acetate extract showed the most potent antioxidant activity evaluated by ferrous ion chelating activity and NO radical scavenging activity. Nevertheless, n-butanol extract was more effective in inhibiting linoleic acid peroxidation. A significant difference between n-butanol extract and ethyl acetate extract in nitrite scavenging activity ${\beta}$-carotene bleaching assays could not be found. Also, the results of this study showed that thermal treatment yam could be used as easily accessible source of natural antioxidants and as a possible food supplement.

• Bulletin of the Korean Chemical Society
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• 제23권11호
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• pp.1635-1639
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• 2002

A new solvent polymeric membrane sensor based on tetra(p-chlorophenyl)porphyrinato manganese (III) acetate is described which demonstrates excellent selectivity toward the triiodide ion. The electrode has a linear dynamic range between 1.0 ${\times}$ $10^{-2}$ M and 7.0 ${\times}$$10^{-6}$M with a Nernstian slope of $-59.6{\pm}1$ mV per decade and a detection limit of 5.0 ${\times}$$10^{-6}$M. The proposed sensor revealed good selectivities for triiodide over a wide variety of other anions and could be used in a pH range 2-9. The electrode can be used for at least two months without any considerable divergence in potential. It was applied as indicator electrode in potentiometric titration of the triiodide and As(III) ions.

• 한국세라믹학회지
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• 제33권7호
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• pp.743-754
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• 1996

In this study (Ba1-xPbx)TiO3 was synthesized by modified oxalate process in order to prevent vaporization of PbO through low temperature synthesis climinate Cl ion reproducibly substitute Pb for by and uniformly distribute ion (Ba1-xPbx)TiO3 was synthesized by coprecipitation of lead acetate barium acetate and ammonium titanyl oxalate have been used as starting materials. The substitution of Pb for Ba was reproducibly possible synthetic temperature of perovskite structure becomes lowed as the Pb concentration increases and fine partic-les (specific surface are :7.2 cm2/g) were obtained, BaTiO3 powders calcined at 90$0^{\circ}C$ for 3 hours were cubic from in XRD analysis and as Pb content was increases evident split of tetragonal peaks could be observed The optimum conditions to synthesize (Ba,Pb)TiO3 powder are the followings ; synthesis temperature (5$^{\circ}C$)

• Journal of Ginseng Research
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• 제19권2호
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• pp.134-137
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• 1995

Ginseng saponins were analyzed by thermospray (TSP) LCMS method using ODS column and with acetonitrile/ammonium acetate solution. Optimal condition for TSP Lchfs was found as follows: capillary temperature: 33$0^{\circ}C$ repelled voltage: 200 V, and concentration of ammonium acetate: 0. 05 M. Panaxadiol and panaxatriol type saponins showed characteristic fragment ions. The calibration curve of ginseng saponin showed good linearity with a correlation coefficient of 0.99. Detection limits using selected ion monitoring (SIM) technique were improved by 10~200 times compared to conventional HPLCnnr detection method.

• Bulletin of the Korean Chemical Society
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• 제16권7호
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• pp.672-674
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• 1995

• Bulletin of the Korean Chemical Society
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• 제22권6호
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• pp.611-615
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• 2001

A new polynuclear complex of manganese stearate has been prepared by substitution of acetate with stearic acid. The stearate ion with long alkyl chain was used to isolate molecular $Mn_{12}$ cluster from each other. The $Mn_{12}$-stearate compound prepared is soluble in most organic solvents and resistant against water catalyzed reduction. The $Mn_{12}$-stearate compound shows similar electrochemical, magnetic properties to the pristine $Mn_{12}$-acetate.