• Journal of the Korean Chemical Society
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• v.29 no.5
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• pp.516-521
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• 1985

Ethylenediamine-triacetatocobalt (III) complexes with an ammine, an ethylene-diamine, and a trimethylenediamine as the unidentate ligand were prepared, and were isolated as only one isomer for each case by the Dowex 50W-X8, cation exchange resin in $H^+$ form. The geometrical isomer of these complexes have been assigned cis-equatorial form in the three possible geometrical isomers from the elemental analysis, pH titration, IR, NMR, and electronic absorption spectrum. It was found that $[CoN_3O_3]$ system of the meridional form with multidentate ligand have the first absorption band of the largely splitting pattern, and that the diamines (ethylenediamine, trimethylenediamine) have coordinated to the central cobalt (III) ion as a unidentate ligand.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.158-166
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• 2004

The optimal conditions are obtained for the decomposition of solid radioactive wastes, including ion exchange resin, zeolite, active charcoal, and sludge from nuclear power plant. In the process of decomposing the radioactive wastes were used the microwave acid digestion method with mixed acid. The solution after acid digestion by the following method was colorless and transparent. Each solution was analyzed with ICP-AES and AAS and the recovery yield for 5 different elements added the simulated radioactive wastes were over 94%. As an effective pre-treatment, the proposed microwave acid digestion conditions concerning the chemical trait of each radioactive waste are expected to be generally applied to above-mentioned radioactive wastes from nuclear power plant hereafter.

• KSBB Journal
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• v.25 no.4
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• pp.395-400
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• 2010

Papain hydrolysate of fibroin was found to be mainly composed of several even-numbered peptides that can be produced at a large scale and can be used as a precursor for biological fine-chemicals such as peptide detergents. Thus, the hydrolysate was further modified to synthesize a peptide mixture of glyceryl esters using the identical enzyme for the production of such chemicals. Formation of glyceryl ester of each peptide was confirmed by identifying peaks of the nominal mass shift of +74 Da in mass spectrometry. Analysis of the mass spectra indicated that glyceryl esters of di- and tetra-peptides were the major constituents of the mixture and that alanylglycine was most preferentially esterified. It also suggests that papain prefers dipeptide to tetrapeptide and alanine to serine or tyrosine at $P_2$ position as substrate for glyceryl esterification. The glyceryl esters were recovered using ion exchange resin and the yield of glyceryl esterification recorded was 17.8% by weight.

• Membrane Journal
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• v.24 no.2
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• pp.167-175
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• 2014

For selectively permeable membrane based on cellulose acetate butyrate (CAB) and polyethyleneimine (PEI) with water vapor transportability and DMMP protective performance, we intended to improve protective performance of the membrane against CEES using several additives. Results showed that CAB/PEI membranes possessed performance with good water vapor permeation (${\geq}1,800g/m^2/day$) and enhanced protective capability against CEES contamination ($7.1{\sim}11.5{\mu}g/cm^2{\cdot}day$). Of these membranes, the membrane containing $Ag^+$ ion and ionic exchange resin showed the best protective performance. And, we identified that the CAB/PEI membranes show excellent protection against aerosols with various particle sizes ($0.005{\sim}3{\mu}m$) simulating biological agents.

• Polymer(Korea)
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• v.24 no.4
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• pp.571-577
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• 2000

A new type of filler for epoxy-clay nanocomposites has been prepared by the reaction of octadecyltrimethylammonium bromide and layered sodium montmorillonite (MMT) via an ion-exchange reaction. The gallery space was further modified by grafting the aminopropyl groups via a reaction between a octadecyltrimethylammonium-MMT and 3-aminopropyltriethoxysilane (APS). The interlayer modification of MMT was confirmed by XRD, IR, and solid-state $^{29}$ Si CP/MAS NMR. Furthermore, clay-polymer nanocomposites have been synthesized by the polymerization of diglycidyl ether of bisphenol A(DGEBA) and $C_{18}$ H$_{37}$ N($CH_3$)$_3$-APS-MMT. The resulting hybrid nanocomposites were characterized by XRD, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The results proved that the organomontmorillonite could be exfoliated and uniformly dispersed in the epoxy matrix.

• Korean Journal of Microbiology
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• v.1 no.1
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• pp.48-50
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• 1963

The authors have investigated about the microbial contamination of goods which is a criterion of hygienic control. Conducting on investigation, a special attention has been paid on the rate of microbial contamination in the goods, especially in manufacturing process of the softdrink. The authors also made an experiment on total microbes which is the criterion of contamination in each step of the process and in raw materials together with materials to be used for subdividing. Results obtained were as follows : 1) The orgin of microbial contamination was found in bottle cap and in tap water, that is, there appeared 9 colony per ml in bottle cap and 31-74 colony per ml in tap water, respectively. 2) It was found that microbial contamination are 4 colony per ml in average through year. However, it appeared 1 colony per ml in winter and 8 colony per ml in summer. 3) Coliform groups are not detected in goods through a year. 4) There was no variation in number of total microbes after ion exchange resin passage in purification process of tap water. 5) The number of microbes in goods are decreased when the raw materials are treated in high temperature short time (HTST) sterilization.

• Journal of Microbiology and Biotechnology
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• v.20 no.8
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• pp.1243-1250
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• 2010

A cDNA encoding a cysteine protease inhibitor (CPI) was isolated from the cDNA library of clamworm Perinereis aibuhitensis Grube. The deduced amino acid sequence analysis showed that the protein had 51%, 48%, and 48% identity with Zgc:153129 from Danio rerio, cystatin B from Theromyzon tessulatum, and the ChainA, stefin B tetramer from Homo sapiens, respectively. The gene was cloned into the intracellular expression vector pET-15b and expressed in Escherichia coli. The recombinant CPI (PA-CPI) was purified by affinity chromatography on Ni-charged resin and ion-exchange chromatography on DEAE-Sepharose FF. The relative molecular mass of PA-CPI was 16 kDa as deduced by SDS-PAGE. Activity analysis showed that the recombinant protein could inhibit the proteolytic activity of papain. A constitutive and secretive expression vector was also constructed, and the cDNA encoding CPI was subcloned into the vector for extracellular expression. Western blotting analysis results showed that the PA-CPI was secreted into the medium. Bioassay demonstrated that E. coli DH5${\alpha}$ harboring pUC18ompAcat-CPI showed a significant difference in mortality to the Asian longhorned beetle Anoplophora glabripennis compared with untransformed E. coli DH5${\alpha}$ and control.

• Korean Journal of Pharmacognosy
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• v.1 no.3
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• pp.93-99
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• 1970

There have been reported by several workers for the isolation and determination of the amine derivatives as Metbylephedrine Hydrochloride and Ephedrine Hydrochloride adopting neutralization method, steam distillation method, non-aqous titration method, ion-exchange resin method, titration method after acetylation, colorimetric method, gravimetric method, iodine titration method and gas chromatography. Those methods mentioned in above, can be practically applied for the sample which is not mixed one mith the other amine compounds. Presently, it has not shown on the isolative determination of the mixed sample of amine derivatives. In this paper, it is discussed on the isolative determination of Methylephedrine Hydrochloride as the tertiary amine compound and Ephedrine Hydrochloride as the secondary amine compound. According to the results of the experiment, it could be summarized as follows: 1. There is no time-variation on the color reaction of Methylephedrine Hydrochloride and Ephedrine Hydrochloride with the color reagent, bromcresolgreen. And Methylephedrine Hydrochloride and Ephedrine Hydrochloride, respectively, can be determined spectrophotometrically by means oft his color reaction. 2. For the isolation of Methylephedrine Hydrochloride and Ephedrine Hydrochloride from the mixed sample, Methylephedrine Hydrochloride can be eluted by chloroform, while Ephedrine Hydrochloride by the mixed solvent of chloroform and ethylalcohol (2:1), from the celite column adsorbed at pH6.4 followed by extraction with ether undersodium hydroxide alkali re action. 3. When the sample is mixed with quinine hydrochloride, dihydrocodeine bitartate, and noscapine, these mixed compounds can be eliminated by means of stram distillation. 4. When the sample is mixed with chlorpheniramine maleate, dextromethorphan hydrobromide and diphenhydramine hydrochloride, the mixed compounds can be eliminated by means of steam distillation and celite adsorption column chromatography, In conclusion, the isolative determination method for Methylephedrine Hydrochloride and Ephedrine Hydrochloride studied in this paper, indicates with the excellent reproducibility and accuracy.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.162-170
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• 1993

Vapor-phase ETBE(ethyl tert-butyl ether) synthesis from TBA(tert-butyl alcohol) and ethanol was carried over solid acid catalysts such as heteropoly acids and proton type zeolites. Heteropoly acids were more active than proton type zeolites and $H_4SiW_{12}O_{40}$ catalyst showed about the same activity as Amberlyst-15 ion exchange resin catalyst used as an industrial catalyst in ETBE synthesis. The catalytic activity of transition metal exchanged heteropoly acids was greatly enhanced, because new acid site was generated with hydrogen reduction. This effect of hydrogen reduction was related to the reduction characteristics of catalysts and the order of reducibility was $Ag^+$>$Cu^{2+}$>$Fe^{2+}$.

• Nuclear Engineering and Technology
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• v.23 no.4
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• pp.374-386
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• 1991

Various factors affecting the teachability of Cs-137 in cement matrix have been investigated. Factors investigated include such as pressure curing, vibration curing, pressure leaching, the effect of the clay addition, ion-exchange resin(IRN-77) addition, and $CO_2$or air injection. Leaching experiments were conducted by the method recommended by IAEA. To analyze the experimental results, pore structure analysis of cement matrices was carried out by BET method. Cement matrices may not contact directly with underground water in real repository, since the surroundings of disposed drums are filled with backfill. Thus, the effect of backfill to the teachability has been investigated. The well-known diffusion theory was utilized to predict long term leach rate and cumulative fraction leached of Cs-137 or non-radioactive species.