• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1163-1168
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• 1998

Fish tissues were spiked with organophosphorus pesticides (OPPs), mixed with a celite as a drying agent, and dynamically extracted with pure $CO_2$ or modified $CO_2$ for 10 min at different extraction temperatures, pressures and $CO_2$ flow rates. Recoveries of OPPs spiked in jacopever increased with the decrease of extraction temperature and pressure, and decreased with the increase of $CO_2$ flow rates. Modified $CO_2$ extractions with 10% methylene chloride showed a slight increase in the recoveries over pure $CO_2$ extraction. Quantity of fish tissues had great effect on their extraction efficiencies. Recoveries of OPPs were $66.7{\sim}86.3%$ for jacopever, $56.2{\sim}79.2%$ for yellow tail, $57.6{\sim}77.8%$ for blanquillo, $84.2{\sim}96.3%$ for sardine, $74.6{\sim}83.6%$ for mackerel. Application of supercritical carbon dioxide extraction offers an attractive alternative to the use of organic solvents for extraction of pesticide residues from fish tissues.

• International Journal of Highway Engineering
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• v.8 no.4 s.30
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• pp.135-143
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• 2006

This study evaluated the fatigue resistance characteristics of hot-mix recycled asphalt mixtures which were prepared by a new blending method. Since the binder of RAP shows higher viscosity without being rejuvenated in the ordinary recycled mixture, this new(modified) blending method was developed for obtaining more uniform level of binder viscosity in the recycled mixture. Cold-planned RAP was collected and mix design was performed using 15% RAP content for two virgin aggregate, gneiss and granite. Penetration grade of 60-80 asphalt was used in mixing recycled mixture together with a polymer modifier, LDPE. Indirect tensile fatigue tests were carried out to evaluate characteristics of fatigue resistance of performance of recycled asphalt mixtures. The recycled mixtures with LDPE 6% showed higher repeated loading fatigue life. Fatigue life ratio of new(N) mixing method mixtures was approximately 0.6-0.7 before aging and 0.8-1.0 after aging treatment of ordinary(O) mixing method mixture. This means the N mixture becomes stronger with aging process increase. If further aging is treated, N mixture may be showing stronger resistance than O mixture.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.41-46
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• 2012

Arabinoxylan (Ara) rice bran has been shown to be a potent biological response modifier as manifested by stimulation of different arms of the immune system. We examined the effects of Ara rice bran and exercise on the immune function and cytokines in lipopolysaccharide (LPS)-stimulated rats. As the results, tumor necrosis factor-${\alpha}$ as representative inflammatory cytokines showed a significantly lower in Ara supplement group, thus the Ara rice bran had a higher inhibitory activity than the both exercise and control group. However, 4 weeks of exercise training significantly increased inflammatory reactions rather than treatment with Ara in LPS-treated rats. The Ara rice bran acted to decrease the inflammatory reaction. These results suggest that the supplement of Ara rice bran is likely contribute to inflammation response and the Ara rice bran can be used as a possible safe alternative to the immunotherapeutic modalities.

• Analytical Science and Technology
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• v.10 no.6
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• pp.427-432
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• 1997

A selective method for the determination of iron(III) ion with a sodium dodecyl sulfate(SDS) modified glassy carbon electrode was proposed. It was based on the electrostatic attraction and complexation of the SDS modifier, $(DS^-)_n-Fe^{3+}$. The determination of iron(III) ion was performed by a differential pulse voltammetry(DPV), and the reduction peak potential of $(DS^-)_n-Fe^{3+}$ was +0.466(${\pm}0.002$)V vs. Ag/AgCl. For the determination of iron(III) ion, a linear calibration curve was obtained within the iron(III) ion concentration range of $0.50{\times}10^{-5}{\sim}10{\times}10^{-5}mol/L$, and the detection limit was $0.14{\times}10^{-5}mol/L$. $Cu^{2+}$, $Ni^{2+}$, $Co^{2+}$, $Pb^{2+}$, $Zn^{2+}$, and $Mn^{2+}$ showed little or no effect on the determination of iron(III) ion, respectively. But, ion such as each $CN^- $ and $SCN^-$ interfered seriously.

• Analytical Science and Technology
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• v.6 no.1
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• pp.1-8
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• 1993

The purpose of this study is to investigate the elution behavior of monosubstituted phenols and benzenes in micellar liquid chromatographic system, $C_{18}$ column-anionic surfactant, sodium dodecyl sulfate(SDS). The partition coefficients between the micellar pseudophase-water and modified stationary phase-water are calculated by the relationship between solute retention and micellar mobile phase(SDS) composition. The free energy of transfer of solute from water to micelle is also calculated from these values. There is a direct correlation between the hydrophobicity parameters in MLC and corresponding partition data for 1-octanol-water, which indicates that the hydrophobicity of molecules plays an important role in the partition for both systems and that quantitative structure activity relationships(QSAR) are available from studies on micellar partition. The other purpose of this study is to investigate methylene selectivity of alkyl homologous series through correlation between retention and the number of carbons. The correlation between hydrophobicity parameters in MLC and 1-octanol-water partition data was also observed when n-propanol was as a modifier in the mobile phase.

• Sijohaknonchong
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• v.30
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• pp.219-240
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• 2009

Jasan An Whak did research on the essence of Sijo to show that Sijo has some features as a literature. I tried to show the formation process of Sijo theory in 1930s through Jasan's Sijo theory. As a preparatory step for it, I introduced Jasan's Sijo theory released in early 1930s and examined the characteristic aspects of it. Jasan recognized a literature as a directing post that reveals the history of our national spirit. He thought a literature as a foundation for satisfying new age. Also, he recognized the essence of a literature as a emotional expression. He emphasized that a new literature in Joseon age should have not only particularity of Joseon literature but also universality of modern literature. Jasan studied style of Sijo. Because he was at the time of modernization, he used the term, 'style', instead of 'poongkyeok', which had used before modern time. He tried to show linguistic artistry of Sijo through the series of his works about the style of Sijo. Jasan tried to find formal beauty of Sijo in the aspect of rhythm instead of rhyme. And he claimed that poetic words can be lengthened or shortened to be harmonious with the melody of Sijo. In other words, it is possible to change the words of Sijo for harmonizing with a tune. Jasan recognized that the words of Sijo have a musical function as well as a semantic function.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.73-81
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• 1999

This paper was intended to evaluate the effect of the blending condition of pigments on the packing structure of coating color and the interaction between pigments and latices on the optical and interior properties of coated paper. It has been studied many ways to modify the coating structure to induce the interaction among coating components as followings ; 1) to use dispersant for pigment, 2) to control the charge density and the type of surface charge of latex, 3) to support the water retention by adding water retention agent or flow modifier. This paper was performed through the introduction of interaction between pigments which were two kinds of clays and one precipitated calcium carbonate(PCC) and ionic latices of which anionic and amphoteric respectively under the certain blending condition of pigments where their blending ratio of clays to calcium carbonate was 70pph to 30pph. The reason is that packing volume of pigments was highest in that region and thixotropical behavior appears in measuring rheology of coating color. We measured the properties of coating color, interaction with pigments and latex, and properties of coated paper and its printability. As a results, we could find out that amphoteric latex had a great influence on the interaction with pigments, especially clays, no matter what grade and also affected the coating structure significantly in case that this blending condition was 70(clays) to 30(PCC). It produced a powerful effect on the forming of bulky and smooth coating structure and in turn improved the printability of coated paper.

• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.879-888
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• 1992

Separation of the optical isomers of free amino acids by a reversed phase high performance liquid chromatography has been studied by adding a copper(II) complex of L-proline or L-proline derivatives (hydroxy-L-proline, N-benzyl-L-proline, p-xylenyl-L-proline, p-xylenyl-hydroxy-L-proline) in the mobile phase. An OPA postcolumn detection system was used for the detection of amino acids. The chromatographic properties for the free amino acids were discussed in terms of the pH, the kinds and concentration of chelate or organic modifier. The retention behaviors of the free amino acids were considerably different from, those of DNS-amino acids or DABS-amino acids. The enantioselectivity of the free amino acids was better than that of derivatized amino acids. The enantioselectivity between the optical isomers observed by use of the Cu(II)-p-xylenyl-L-proline chiral cheleate was the best among the several copper(II) chelate. A separation mechanism could be illustrated not only by the hydrophobic interaction of the diastereomer with stationary phase but also by the steric effect of the ligand exchange reaction between the free-amino acids and copper chelate.

• Journal of the Korean Solar Energy Society
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• v.28 no.2
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• pp.58-63
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• 2008

This study has analysed power output characteristics of transparent thin-film PV module depending on incidence angle and azimuth. The experiment results showed power outputs of transparent thin-film PV module applied to full-scale mock up model on slope of $90^{\circ},\;30^{\circ},\;0^{\circ}$ to the south. The simulation results was evaluated power outputs of transparent thin-film PV module depending on incidence angle and azimuth after calibrating the experimental and computed data. As a result. the best power output performance of transparent thin-film PV module was obtained at slope of $30^{\circ}$ to the south, producing the annual power output of 977kWh/kWp. The annual power output data demonstrated that the PV module with a slope of $30^{\circ}$ could produce a 68 % higher power output than that with a slope of $90^{\circ}$ with respect to the inclined slope of the module, Furthermore, the PV module facing south showed a 22 % higher power output than that facing to the east in terms of the angle of the azimuth, Specipically. the varying power output with incidence angle of PV module can be resulted from the influence of incidence angle modifier of glass on PV module. That is, the solar energy transmission can be reduced as an increase of incidence angle of PV module. Therefore, when the inclined slope of the PV module was over $70^{\circ}$ there was a significant reduction of power output, and this was caused by the decrease of solar energy transmission in the transparent thin-film PV module.

• KSBB Journal
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• v.19 no.6 s.89
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• pp.427-432
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• 2004

The purpose of this study is to investigate the feasibility of a cosolvent-modified supercritical $CO_2\;(scCO_2)$ extraction technique for the production of licorice extracts with high levels of glabridin. The effects of various parameters such as the type and amount of modifiers, extraction temperature ($40{\sim}80^{\circ}C$) and pressure ($10{\sim}50.0\;MPa$) on the extraction efficiency were examined at a fixed flow rate of 1 mL/min. The organic solvent extraction with pure methanol was also conducted for a quantitative comparison with the $scCO_2$ extraction. The recovery of glabridin from licorice was found to be extremely small for pure $scCO_2$. However, the addition of modifiers such as ethanol and acetone to $scCO_2$ resulted in a significant improvement in the recovery of glabridin. The recovery of glabridin was observed to increase with pressure at a constant temperature. Furthermore, the purity of the glabridin obtained from the $scCO_2$ extraction was higher compared with the organic solvent extraction.