• Journal of the East Asian Society of Dietary Life
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• v.5 no.1
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• pp.87-93
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• 1995

The oxidized mixture of lipid(methyl linoleate) and phenolics(phloroglucinol) at 37$^{\circ}C$, 82$m\ell$ O/min., for 9 days were separated each by C cartridge and silica cartridge making use of different eluting solvent. And the oxidation products were analyzed by HPLC. In conclusion, the oxidized mixture were separated into methyl linoleate and phloroglucinol by cartridge on HPLC. and also in this experiment, separated methyl linoleate and phloroglucinol could be analyzed in the common eluant, water and acetonitrile on HPLC. SEP-PAK cartridges were used almost sample purification until now, but under the various eluting solvents and conditions, cartridge will be expected to mini columns which can separate different polarity materials.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.620-621
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• 2006

• Journal of Photoscience
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• v.6 no.4
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• pp.159-163
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• 1999

The fluorescence quenching of 2-phenyl-5-(4-biphenylyl)-1,3,4-oxadiazole (PBD) and 1,4-di-[2-(5-phenyloxazolyl)]-benzene (POPOP) by aniline has been carried out in different solvent mixtures of dioxane and acetonitrile at room temperature. The quenching is found to be appreciable and a positive deviation from linearity was observed in the Stern-Volmer plot in all the solvent mixtures. Various rate constants for the quenching processes have been determined using a modified Stern-Volmer equation. From the positive deviations of linear Stern-Volmer plots and the dependence of rate constants on the polarity of the solvents, it has been concluded that both static and dynamic quenching processes are responsible for the observed positive deviation in the Stern-Volmer plot.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.558-565
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• 2015

Katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc) leaves were collected, air-dried and extracted with 70% aqueous acetone, then concentrated and sequentially fractionated using n-hexane, methylene chloride ($CH_2Cl_2$), ethylacetate (EtOAc), and $H_2O$. The EtOAc fraction was chromatographed on a Sephadex LH-20 column with various aqueous MeOH eluting solvents and finally treated with acetone-$H_2O$ (7:3, v/v) to isolate a gallotannin. According to the NMR analysis, including HSQC and HMBC, and with the comparison of authentic literature data, the isolate was elucidated as 6-m-digalloyl-1,2,3,4-tetra-O-galloyl ${\beta}$-D-(+)-glucose, one of hydrolyzable tannins and one of gallotannins. The compound was only gallotannin which was firstly isolated from the extracts of Katsura tree leaves, and has not been reported before in domestic tree sources.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.5
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• pp.450-455
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• 2007

LCD color filters have been manufactured in a process called photolithography to date, but various printing methods have been studied currently in response to the trend of low-end LCD panels. Direct Printing Process is a suitable fabrication technique to develope pigment components whose dimensions are in nano. The success of this process depends on the systematic preparation of pigment millbase. Conventional millbase dispersions are constituted of the organic pigments, monomer, dispersant and solvents. An experimental study on the rheology of millbase dispersions is presented. Subsequently, this thesis attempts to find out the dispersive characteristics as well as the selection of pigments, monomers and dispersants in the part of millbase among the stages of manufacturing LCD color filters using the direct printing methods. The dispersive characteristics were shown through analytic devices such as PSA, Rheometer, etc.

• Transactions on Electrical and Electronic Materials
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• v.18 no.6
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• pp.341-344
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• 2017

Infrared (IR) filters were developed to implement integrated three-dimensional (3D) image sensors that are capable of obtaining both color image and depth information at the same time. The combination of light filters applicable to the 3D image sensor is composed of a modified IR cut filter mounted on the objective lens module and on-chip filters such as IR pass filters and color filters. The IR cut filters were fabricated by inorganic $SiO_2/TiO_2$ multilayered thin-film deposition using RF magnetron sputtering. On-chip IR pass filters were synthetized by dissolving various pigments and dyes in organic solvents and by subsequent patterning with photolithography. The fabrication process of the filters is fairly compatible with the complementary metal oxide semiconductor (CMOS) process. Thus, the IR cut filter and IR pass filter combined with conventional color filters are considered successfully applicable to 3D image sensors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.411-416
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• 1997

To examine the free radical scavenging activities from buckwheat, Suwon No. 5 was extracted with various solvents. The seed of Suwon No. 5 had a high contents of carbohydrate, but the vegetable of that had a 31.4% of protein, 28.6% of ash and 25.7% carbohydrate as moisture free basis. Phenols contents of vegetable extracts had higher than those of seed extracts. Acetone extract of vegetable showed the greatest electron donating ability. Butanol and acetone extracts of vegetable showed high inhibitory effect on lipid peroxidation. Acetone extract of vegetable has also excellent activity in the superoxide radical scavenging activity by xanthine/xanthine oxidase-cytochrome c reduction system. The inhibitory effects of extracts on xanthine oxidase were measured. Acetone extract had the strongest inhibitory effect on xanthine oxidase and $IC_{50}$ was 2.2$\mu\textrm{g}$.

• Journal of the Korean Chemical Society
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• v.14 no.2
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• pp.147-153
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• 1970

Band assignments in the infrared absorption spectra of the four substituted Urea compounds, Fenuron (3-phenyl-1,1-dimethyl urea), OMU (3-cyclooctyl-1,1-dimethyl urea), Herban (3-(hexahydro-4,7-methanoidan-5-yl)-l,1-dimethyl urea), and Monuron (3-(p-chlorophenyl)-1,1-dimethyl urea), are made by analyzing the spectra obtained with various solvents. The results suggest that Fenuron and Monuron, each of which contain an unsaturated benzene ring, have a strong tendency to bond through both the amino group and the carbonyl oxygen. Herban and OMU, however, exhibit a much greater change in strength of the carbonyl bond than of the amino bond. It means that a strong hydrogen bonding occurs only at the carbonyl oxygen in the compounds.

• Preventive Nutrition and Food Science
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• v.6 no.2
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• pp.133-135
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• 2001

The edible part of cucurbita moschata Duch, which is commonly used as a Korean traditional medicine as well as a popular food source, was studied to isolate anti-complementary substance. Extracts of Cucurbita moschata Duch showed significant anti-complementary activities on the classical pathway of the complement system. Especially, the ripe Cucurbita moschata Duch had more activity than that of the complement system. Especially, the ripe Cucurbita moschata Duch had more activity than that of the green one in terms of the overall anti-complementary activity. Among the extracts of various organic solvents of the ripe Cucurbita moschata Duch, chloroform and ethyl-acetate extracts, which are non-polar solvent extracts, showed the strongest activities. These results suggest that the major difference in the solvent extraction for the anti-complementary substances depends on the change in the chemical composition such as the fatty acid with the degree of ripening.

• Journal of Biomedical Engineering Research
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• v.8 no.1
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• pp.13-28
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• 1987

Crosslinked poly(2-hydroxyethylmethacrylate) has been prepared by polymerizing 2-hydroxyethyl methacrylate(HEMA) with crosslinkers such as ehyleng glycol dime- thacrylate(EGDMA), tetraethylene glycol dimethacrylate(TEGDMA), tetraethylene glycol diacrylate(TEGDA), divinyl benzene(DVB), and N, N-methylenebisacry- lamide(MAB) in the presence of initiator $\alpha$ , $\alpha$ -azobisisobutyronitrile at 60。C, The synthesized copolymers were identified by FT-lR spectrophotomether. The swelling properties of the crosslinked copolymers in various solvents such as water, methanol, ethanol, n-propanol, and n-butanol were investigated at different temperatures. The thermal properties of the crosslinked coplymers were also measured by differential scanning calorimetry(DSC) and thermogravimetry(TG)