• Korean Journal of Metals and Materials
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• v.49 no.7
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• pp.583-588
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• 2011

$Cd_xZn_{1-x}O$ thin films were grown on quartz substrates by using the sol-gel spin-coating method. The mole fraction, x, of the $Cd_xZn_{1-x}O$ thin films was controlled from 0 to 1 by changes in the content ratio of the cadmium acetate dehydrate [$Cd{(CH_3COO)}_2{\cdot}2H_2O$] and zinc acetate dehydrate [$Zn{(CH_3COO)}_2{\cdot}2H_2O$]. The effects of the mole fraction on the morphological, structural, and optical properties of the $Cd_xZn_{1-x}O$ thin films were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-visible spectroscopy. The $Cd_xZn_{1-x}O$ thin films exhibited the polygonal surface morphology and their grain size was increased ranging from 42.1 to 63.9 nm with the increase in the mole fraction. It was observed that the absorption bandgap of the $Cd_xZn_{1-x}O$ thin films decreased from 3.25 to 2.16 eV as the mole fraction increased and the Urbach energy ($E_U$) values changed inversely to the optical bandgap of the $Cd_xZn_{1-x}O$ thin films.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.1-4
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• 1985

For the systematic investigation of biochemical characteristics of Korean ginseng protein by years, protein fractions were analyzed by the techniques of polyacrylamide gel electrophoresis, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration, while the amino acid composition was studied by amino acid autoanalyzer. Results of polyacrylamide gel electrophoresis and SDS-PAGE showed a few difference in pattern and number of bands depending on the age of the root. However, the number of bands obtained from polyacrylamide gel electrophoresis and SDS-PAGE was 8 and 7 to 11, respectively. When water extracted proteins were fractionated by Sephadex G-200, the main peak among 2 peaks was collected and lyophillized. Its mol. wt. was extimated to be 43,000 by the SDS-PAGE method. In amino acid composition of water extracted protein and main fraction of gel filtration, arginine content was the highest, 47.17% in water extracted protein and 57.36% in main fraction followed by glutamic acid and asparatic acid. On the contrary, cystine and methionine contents were very low in both cases.

• Food Science of Animal Resources
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• v.23 no.2
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• pp.155-160
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• 2003

The purpose of this study was to purify epidermal growth factor(EGF) as growth factor from human colostrum. The effects of purified EGF fraction were directly related to the growth of cells. Results were as follows; After eliminated fat from colostrum, skim milk was obtained. We obtained the EGF fraction by performing ultrafiltration and gel filtration, and then were convicted by SDS-PAGE. The result of analysis of purified EGF fraction by high performance liquid chromatography(HPLC) was shown a peak at 31.185 min period. And it was similar with standard EGF that was shown a peak at 31.545 min. 10 ng of EGF was contained in 10 mg/mL through immunoassay to measure EGF content from isolated fraction. After SDS-PAGE, isolation degree of purified fraction was convicted through western blotting. BALB/3T3 cell was the most effectively stimulated and proliferated at 1 mg/mL concentration of the purified EGF fraction and percentage of cell proliferation was about 95%. In the case of IEC-6 cell, that was about 71%.

• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.25-28
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• 2000

The experiments were carried out to investigate the antimicrobial activity and the content of isoflavonoids each fraction of the methanol extract from Korean arrowroots. The strongest antimicrobical fraction of the methanol extract was the etylacetate fraction and the other fraction was not detected antimicrobial activity. The yield of the ethylacetate fractation was 7~9% of the methanol extract of Korean arrowroot TLC was carried out using silical gel plate and CH$_2$C1$_2$- $CH_3$OH(7 : 3) and puerarin, daizin were detected by spraying 10% H$_2$SO$_4$ and Rf was 0.60 and 0.69, respectively. Puerarin, daidzin and daidzein contents were determined of the ethylacetate fraction of the sample Puerarin and daidzin contents were abundant in the samples of November, while daidzein content was abundant in the sample of Februery.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.413-417
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• 2003

The last few decades have seen drastic growth in the use of brominated flame retardants(BFRs). There is the problems of polybrominated dibenzo-p-dioxins(PBDDS) and polybrominated dibenzofurans(PBDFs) generation as by-products in combustion process of BFRs. PBDDs/PBDFs are highlighted the new pollutants of environmental contamination, recently. In this study, the 10 kinds of PBDDs/PBDFs standards were used to perform the experiments of recoveries. The analysis of PBDDs/PBDFs in soil environmental samples. was carried out. In silica gel column cleanup, PBDDs/PBDFs eluted until 80mL of n-hexane, and the recovery was obtained 73∼105%. In multi-layer silica gel column cleanup, the recovery was obtained 56∼125% with various elution solvents. In alumina clean process, the standard mixture(PBDES, PBDDs/PBDFs) eluted the first fraction of 2% dichloromethane with n-hexane in the range of 0∼100mL, PBDEs compounds eluted in the second fraction of 50% dichloromethane with n-hexane. In activated carbon column cleanup, the PBBEs eluted to the first fraction(n-hexane) and second fraction(toluene), but PBDDs/PBDFs only eluted to the second fraction. The analytical methods of PBDDs/PBDFs for soil was established based on the experimental results of the environmental samples.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.2
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• pp.93-98
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• 2022

To assess the feasibility of silk sericin for non-textile application, the storage stability and biological safety of sericin were examined. It was extracted at 37℃, 70℃, 100℃, and 121℃ for 1, 3, and 5 h to elucidate the effect of extraction condition on the stability and safety of silk sericin. The solubility was increased till approximately 26% with extraction temperature of 121℃ for 1 h. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the molecular weight distribution depended on the extraction conditions. Extracted sericin displayed typical UV absorption bands upon spectrometric analysis. To examine the reproducibility of its obtained conformation, sericin was extracted thrice and its circular dichroism (CD) spectra was measured each time. Most CD spectra showed reproducibility regardless of temperature and time except under 100℃ extraction condition. The diversity of CD spectrum showed gradual reduction and was finally coincident with extraction time from 1 to 5 h. Notably, sericin has a negative peak of approximately 200 nm attributed to random coil conformation, regardless of extraction condition. However, at the 100℃ extraction condition, sericin showed both bands to be negative bands of approximately 200 and 220 nm, respectively. Sericin was centrifuged to determine the stability of storage conditions. The sericin extracted at 100℃ and 121℃ for 1 h was found to form gel rapidly within 1 h, but at 121℃ condition, the gel fraction was approximately 20% within 1 h which retained its phase regardless of storage time. The gel fraction of sericin extracted at 100℃ for 5 h increased with time, however at the 121℃ for 5 h condition, the gel fraction was measured to be less than 10% regardless of increase in storage time. Petriflim^TM AC plates test showed that sericin was safe from aerobic bacteria activity by extraction under high temperature.

• Korean Journal of Animal Reproduction
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• v.12 no.1
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• pp.24-30
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• 1988

These experiments were carried out to develop new techniques for In Vitro separatin of X-and Y-bearing spermatozoa. The bull semen was applied to the various Gel-Columns filled with swellen Sephadex G-50 Fine and then elutriated wtih Locke solution (elutriation rate; 1ml/3-4min., 1ml/1-2min.). Elutriated solution was fractionated into 1ml by automatic Fraction Collector and spermatozoa included in each fraction were subjected to the estimation of viability and recovery rate, and to B-body test. The results obtained in these experiments were summarized as follows: 1. When the column size and the elutriation rate were adjusted to 15$\times$1.6cm and 1ml/3-4min., respectively, the highest sperm concentration was obtained from the 8th to the 12th fraction. 2. As a trend, the viability of spermatozoa was improved by chromatography, and the degree of improvement ranged 5 to 10 percentage. 3. The average recovery rate of spermatozoa applied to column was 73.2 percentage and ranged 52.6 to 81.3 percentage. 4. The lowest rate of B-body bearing spermatozoa following chromatography was obtained when the column size and the elutriation rate were adjusted to 15$\times$0.8cm and 1ml/1-2min., respectively.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.04a
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• pp.28-30
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• 2008

Poly(ethylene oxide)(PEO) of molecular weight of 300,000 was crosslinked by exposure to UV irradiation. Photochemical crosslinking of PEO occurred by UV irradiation and the presence of benzophenone in the film which acts as a hydrogen-abstracting agent. Percent conversion of the polymer into gel as well as water absorbency were investigated gravimetrically. Gel fraction and water absorbency of PEO films increased with increasing UV energy. In case of photocrosslinked PEO films with benzophenone, gel fraction increased up to about 90%. The thermal behavior of crosslinked PEO films was studied by thermogravimetric analysis. The maximum decomposition temperature increased with increasing UV energy and benzophenone concentration.

• YAKHAK HOEJI
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• v.25 no.4
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• pp.137-143
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• 1981

In order to confirm the exact antipyretic component in the earthworm, etherial extract of American earthworm(Red Worm) was fractionated into five fractions by using silica gel column chromatography and thin layer chromatography. The fraction including free fatty acids was found to possess artipyretic response and standard arachidonic acid showed marked antipyretic response on typhoid vaccinated rabbits. Arachidonic acid was identified from the free fatty acid fraction of the earthworm by using gas liquid chromatography. Thus it was considered that the antipyretic activity of the free fatty acid may be due to the presence of arachidonic acid. Lipid-free earthworm powder was extracted with phosphate buffer (pH, 8.0, 0.1M) and all the proteins was salted out by ammonium sulfate. The crude precipitate was dialyzed and the impure proteins were eliminated at pH 5.4 and 4.6. The remaining protein solution was fractionated with various concentrations of acetone. The acetone fractions were identified by using S.D.S. polyacrylamide gel electrophoresis and disc gel electrophoresis. The precipitate at 85% acetone concentration and the remaining proteins in the supernatant did not exhibit the antipyretic activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.1059-1065
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• 2003

Antimicrobial activity of Mokdan bark (Paeonia suffruticosa $A_{NDR}$) was investigated. Methanol extract of dried Mokdan was fractionated to hexane, chloroform, ethylacetate, butanol and aqueous fraction. Ethylacetate fraction among these fractions showed the highest inhibitory effect on the microorganisms such as L. monocytogenes, and E. coli at 500 $\mu\textrm{g}$/disc. Ethylacetate fraction was further fractionated into 3 fractions by silica gel column and thin layer chromatography (TLC). The results showed that ethylacetate fractions No. 1 and 2 had the highest antimicrobial activity. They were mixed again, reseparated, and 3 fractions were obtained. Among them, No. 1 had the highest inhibitory effect on the microorganisms, No. 1 fraction was identified as isobutyl isopentanoate by HPLC, and GC-MS.