• Journal of the Korean Chemical Society
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• v.15 no.2
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• pp.49-54
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• 1971

It is shown that the impurities of Cu(II), Pb(II), Zn(II) and Ag(I) in Bismuth metal and the components of Pb(II), Zn(II) and Sn(IV) in Bismuth alloy are separated into their components from each other by elutions through $3.14cm^2{\times}10cm$ cation exchange resin, $Dowex\;50w\;{\times}\;8$ (100~200 mesh), column with the mixed solutions of HAc and NaAc as the eluents. The elution curve of Fe(III) has a long tailing and is not separated quantitatively from Bi(III). The eluents used for this separation are as follows; 1M HAc + 0.1M NaAc (pH 3.36) for Fe(III) and Bi (III). 0.3M HAc + 0.3M NaAc (pH 4.70) for Cu(II), Pb(II) and Zn(II). 0.5M HAc + 0.5M NaAc (pH4.70) for Ag(I) and Sn(IV). The analysis of cations eluted are carried out by spectrophotometry and EDTA titrimetry. Their recoveries are more than 99%.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.345-349
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• 1997

고준위 방사성 액체폐기물에서 얻어지는 백금족 금속(Pd, Rh, Ru) 들의 분리 및 정제방법으로 강염기성 음이온교환수지를 사용하여본 결과 상용 수지중에서 Dowex 1 $\times$ 8 이 IRN-78 에 비하여 저 농도의 질산 농도에서 Pd(II) 의 분리 및 정제시 우수한 흡착성을 보여 주었으며 Rh(III) 의 흡착은 Pd(II) 의 것보다 훨씬 낮은 값을 보여 주었다. 이 수지들의 백금족 금속에 대한 흡착성을 문헌에 보고된 실험 결과들과 비교 검토하여 본 바 이온 그룹으로 3급 및 4급 Benzimidazole을 가지는 수지에 비하여 훨씬 낮은 값을 나타내었다. 따라서 실용성이 큰 강염기성 음이온수지로서는 Benzimidazole과 같은 혼합 아민 그룹을 지닌 수지가 가장 접합할 것으로 전망되었다.

• Journal of the Korean Chemical Society
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• v.15 no.2
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• pp.45-48
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• 1971

The various eluents have been used for the separations of alkaline earth metals by elutions through cation exchange resin column by many investigators. We find, the mixed solution of 1M HAc and 1M NaAc (pH 4.75) is the best eluent for this purpose, becouse the one step elution through 7cm Dowex 50w${\times}$8(100~200mesh) resin column with this eluent, gives the quantitative separation. When 2M NaAc is used as a eluent Sr(II) and Ba(II) is separated easily without any contamination of Mg(II) andCa(II). The Ca-Pb alloy which is composed of Cu, Ca, Sr, Ba and abundance of Pb metal is separated quantitatively into its components by the two step elution with 0.3M HAc + 0.3M NaAc(PH 4.75) and 0.5M HAc + 0.5M NaAc(PH 4.75) as eluents through 10cm resin column.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.630-634
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• 2011

Enzymatic hydrolysate of porphyran from Porphyra yezoensis was prepared by treatment with ${\beta}$-agarase. The hydrolysate was fractioned into molecular sizes of <3, 3-30, and 30-300 kDa using an ultrafiltration membrane. The membrane fractions were further separated into neutral and anionic fractions using Dowex $1{\times}8$ ion exchange chromatography. After hydrolysis of porphyran with ${\beta}$-agarase, 23.2% of the starting porphyran was recovered as a neutral fraction of low-molecular weight (<3 kDa), and 28.9% remained as an enzyme-resistant anionic fraction of high molecular weight (>300 kDa). Desulfation of porphyran and $^{13}C$-NMR analysis of the anionic fraction of low molecular weight (<3 kDa) showed that the anionic fraction has a backbone consisting of 3-linked ${\beta}$-D-galactose units alternating with either 4-linked a-L-galactose 6-sulfate or 3, 6-anhydro-a-L-galactose units. These results indicate that porphryan is a copolymer of two moieties, about 25% of which are composed of neoagarose moieties and 75% as anionic moieties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.3
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• pp.163-168
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• 1974

The present paper deals with the degradation of nucleotides in the muscle of sea mussel, Mytilus edulis, during drying. Three kinds of samples, raw, hot-air dried, and steamed-and-hot air dried were prepared and the contents of nucleotides were determined by ion exchange chromatography on columns of Dowex 1, X8. ATP and ADP were dominant in the raw muscle showed about $8{\mu}moles/g$, dry basis, respectively. The rate of degadation of ATP was very slow during drying compared with those of fish. The accumulation of ADP and AMP were observed during drying and the amount of total nucleotides (ATP+ADP+AMP) were not decreased remarkably by drying process. IMP was not detected in the all of the samples examined, however, the contents of inosine and hypoxanthine were increased during drying. In case of inosine contents, the hot-air dried sample marked an exceedingly high value equivalent to 8 times of the raw sample whereas steamed-and-hot air dried sample showed 2 times of raw samples.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.256-259
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• 2004

[ $V_2O_5$ ] 나노선의 구조 분석을 위해 STM(Scanning Tunneling Microscopy)과 TEM(Transmission Electron Microscopy)을 이용하여 단일 $V_2O_5$ 나노선의 이미지를 얻었다. $V_2O_5$ 나노선은 상온에서 ammonium metavanadate$(NH_4VO_3)$와 양이온 교환수지$(DOWEX50{\times}8-100)$를 2차 증류수에 섞어 합성하였다. STM 시료는 3-APS(3-aminopropyltriethoxysilane)를 전 처리한 실리콘 기판에 $V_2O_5$ 나노선을 올려 만들었고, TEM 시료는 200 mesh/copper 그리드에 침전시켜 준비하였다. STM과 TEM의 결과로부터 $V_2O_5$ 나노선의 기하학적 단면이 $1.5nm{\times}10nm$에 거의 근사하는 것을 확인하였으며 두 이미지의 비교를 통해 $V_2O_5$ 나노선의 표면상태에 대해 논의하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1401-1407
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• 2008

1-Deoxynojirimycin (DNJ) is a strong $\alpha$-glucosidase inhibitor which inhibits hyperglycemia in animals. To select the Bacillus strains highly producing DNJ, 4,000 strains were isolated from soil and grain samples. By the inhibitory activity against $\alpha$-glucosidase, nine Bacillus strains were selected and then identified by 16S rDNA sequencing. B. subtilis S10 was finally selected as the best strain for the production of DNJ. Various carbon sources and nitrogen sources in culture medium were evaluated for the highest production of DNJ. As the results, the optimized concentration of carbon source and nitrogen source was 1.0% galactose and 1.6% polypeptone and the concentration of DNJ produced was 0.75 g/L. The effect of culture supernatant of B. subtilis S10 on lowering blood glucose level was investigated in streptozotocin (STZ)-induced diabetic mice model. Mice were randomly assigned to control group (saline) and three test groups such as acarbose group, silkworm powder group and B. subtilis S10 group. After eight-week oral feeding, blood glucose levels of the B. subtilis S10 and silkworm powder groups were respectively $209.1{\pm}19.6\;mg/dL$ (59.1%) and $208.6{\pm}39.8\;mg/dL$ (59.0%) lower than $510{\pm}10\;mg/dL$ of the control group. These results indicated that the culture supernatant of B. subtilis S10 was able to reduce the blood glucose level in STZ-induced diabetic mice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.2
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• pp.220-228
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• 2017

Effects of extraction methods on reducing concentrations of pro-oxidants (total iron and protein) of salmon was determined. For development of the extraction process, the effectiveness of several extraction methods was determined and compared, including heat treatment (60, 80, and $100^{\circ}C$), ion exchange and carboxymethyl (CM)-cellulose column chromatography, and ultrafiltration (UF). Protein, total iron, and anserine contents of salmon extracts were 23.64 mg/mL, $16.20{\mu}g/mL$, and 5.47 mg/mL in non-heated extracts, 7.40 mg/mL, $2.32{\mu}g/mL$, and 5.20 mg/mL in heated extracts at $60^{\circ}C$, 7.64 mg/mL, $1.20{\mu}g/mL$, and 5.21 mg/mL at $80^{\circ}C$, and 7.04 mg/mL, $0.68{\mu}g/mL$, and 4.04 mg/mL at $100^{\circ}C$, respectively. Heating and UF decreased contents of protein and total iron, whereas only UF slightly decreased anserine content. Application of the primary ion exchange method increased the content of anserine up to 16%. Protein and total iron contents by the primary ion exchange method decreased by 70 and 98%, respectively. Secondary ion exchange (CM-cellulose) treatment after primary ion exchange and UF resulted in lower anserine content than the primary ion exchange method. However, the content of impurities (protein, total iron) was lower than in all other salmon extracts. Therefore, primary ion exchange, UF, and secondary ion exchange method were the best extraction processes in this study.