• Journal of Sericultural and Entomological Science
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• v.25 no.2
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• pp.44-50
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• 1984

The effects of sodium pyrophosphate, sodium tripolyphosposphate and ethylene diamine tetraacetic acid as a degumming aid reagent were investigated under the conditions of underground water and dimineralized water for the scouring water sources. The changes of water qualities by adding the condensed sodium phosphates and the physical properties of scoured silk fabric were examined, respectively. 1. The water hardness of underground water was decreased by adding the condensed sodium phosphates and it was further reduced according to the increasing temperature. The water hardness reducing power of sodium pyrophosphate was a little stronger than that of sodium tripolyphosphate. 2. The sodium silicate as an alkaline reagant for scouring decreased the water hardness, but the sodium carbonate increased it in the underground water. 3. The pH value of 0.4% soap and 0.25% sodium silicate mixed solution after boiling was. 9.80, but it was leveled upto 9.90 by adding 0.05% sodium pyrophosphate and upto 9.95 by 0.02% ehtylene diamine tetraacetic acid, respectively. 4. The masking action of Fe$\^$3+/ ions dissolved in the scouring water was more remarkable by ethylene diamine tetraacetic acid than by the condensed sodium phosphates. Of the condensations, sodium tripolyphosphate was more effective than sodium pyrophosphate in the action. 5. Genrally, the dimineralized water scouring increased the boil-off ratio with reducing the flexural rigidity of fabric which was negatively related with the favorablility of hand-touch more than the underground one did. 6. Under the underground water scouring, the addition of ethylene diamine tetraacetic acid increased the boil-of ratio and compressive elasticity of fabric with reducing the flexural rigidity more than that of the condensed sodium phosphates did. 7 The additions of sodium tripolyphosphate and ethylene diamine tetraacetic acid reduced the flexural rigidity of fabric with raising the boil-off ratio even in the dimineralized water scouring, but there was no sifnificant difference between both of them.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.2
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• pp.75-81
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• 2011

Hydroxyapatite (HAP) crystals with hexagonal structure have been successfully synthesized by using EDTA(ethylene diamine tetraacetic acid) as chelate under hydrothermal condition. The as-prepared HAp powders were characterized by XRD and SEM. The XRD result indicated that the products were preferentially oriented along c-axis. The SEM photographs showed that the morphology of the HAp crystals was well controlled by the reaction parameters such as temperature, pH value, and the molar ratio of EDTA/Ca.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1236-1241
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• 2007

The feasibility of soil washing was investigated in the laboratory to treat heavy metals-contaminated railway soil. Various organic acids including ethylene diamine tetraacetic acid (EDTA) and citric acid as well as inorganic acids such as hydrochloric acid (HCl) and phosphoric acid were tested to evaluate washing efficiency. Generally, inorganic acid showed higher removal efficiency compared to organic acids. Specially, EDTA, which are well known as most effective washing agent to remove heavy metals from soil, was not efficient to remove heavy metals in this study. Among washing agents tested in this study, HCl was most effective. The removal of Cd, Cu, and Pb was high, however, that for Zn and Ni was less than 30% with 0.5 M HCl. This difference comes from analytical methods (Korean Standard Test Method for Soil). Aqua regia was used to extract Zn and Ni, however 0.1 N HCl was used for other metals. As a result, simple washing technology is not effective, to treat railway contaminated soil with heavy metals.

• Journal of Soil and Groundwater Environment
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• v.14 no.1
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• pp.78-82
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• 2009

In this study, the feasibility of soil washing and soil flushing was investigated to treat Zn-contaminated railroad soil. Various organic acids including ethylene diamine tetraacetic acid (EDTA) and citric acid as well as inorganic acids such as hydrochloric acid (HCl) and phosphoric acid were tested to evaluate washing efficiency. Generally, inorganic acid showed higher removal efficiency compared to organic acids. Particularly, EDTA, well known as the most effective washing agent for removal of heavy metals from soil, was not efficient to remove zinc in this study. Among washing agents tested in this study, HCl was the most effective. However, it is not effective to use HCl solution over 0.1 M concentration. Sequential process using HCl was effective to enhance the removal efficiency of zinc. In column test, the removal efficiency of Zn was 27%. Accordingly, it is feasible to treat Zn-contaminated railroad soil using soil washing or flushing with HCI.

• Journal of Environmental Health Sciences
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• v.28 no.5
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• pp.53-58
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• 2002

A method for the determination of lead(II) ion using a nafion-EDTA(ethylene diamine tetraacetic acid)-glycerol modified glassy carbon electrode was proposed. Lead(II) ion is accumulated at the electrode by complexation and electrostatic attraction with nafion-EDTA-glycerol and detected at -0.560$\pm$0.015V (vs. Ag/AgCl) by differential pulse voltammetry. For the determination of lead(II) ion, a standard calibration curve if obtained from 10$^{-9}$ M lead(II) ion to 10$^{-7}$ M, and the detection limit(3s) is as low as 5.0$\times$10$^{-10}$ M.

• Journal of Environmental Science International
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• v.12 no.5
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• pp.559-564
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• 2003

The specific ion effects are observed in the alumina-metal EDTA(Ethylene Diamine Tetraacetic Acid) system. These effects seem to be associated with the fluidity of the metal ion in the complex. A consideration of the order of adsorption of the complexes on alumina indicates that a specific ion effect also affects the stability of the system. It is clear that EDTA and its heavy metal complexes have a significant effect on the dewaterability of alumina. These effects are not well represented by zeta potential measurements, especially for EDTA alone. With the nonspeciating complexes, though, the maximum permeability is predicted by the pH$\_$zpc/ from zeta potential measurements. At other pH value, the refiltration rate is better predicted by the state of coagulation as measured by log W.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.176-182
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• 2003

An alkaline fibrinolytic protease-producing bacteria was isolated front Korean traditional soy sauce and identified as Bacillus subtilis K7 from the results of analyses of its morphological and physiological properties, $API^{\circledR}$, and Biolog system. The enzyme was purified by 75% ammonium sulfate fractionation, QAE-Sephadex anion and SP-Sephadex cation exchange column chromatography and Sephadex G-100 gel filtration. The specific activity of the purified enByme was 233.9 unit/mg protein and the yield of enzyme was 3.8%. The homogeneity of the purified enzyme was confirmed by polyacrylamide gel electrophoresis. Molecular mass of the enzyme was estimated about 21,500 Da by SDS-polyacrylamide get electrophoresis and gel chromatography. The optimum temperature and pH for the enzyme activity were $40^{\circ}C$ and 9.0, respectively. The enzyme was stable in a pH range of 5.0 to 12.0, and 60% of its activity was lost on heat treatment at $50^{\circ}C$ for 20 min. The activity of the purified enzyme was inhibited by the presence of $Fe^{2+},\;Ag^{2+},\;Cu6{2+}$, iodoacetate, ethylene diamine tetraacetic acid (EDTA), and trans-1,2-diaminocycloheane-N,N,N',N'-tetraacetic acid (CDTA). The results indicates that the enzyme requires a metal ion for its enzymatic activity.

• The Korean Journal of Mycology
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• v.32 no.2
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• pp.125-129
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• 2004

A carboxymethyl cellulase (CMCase) bas been isolated and purified from Lampteromyces japonicus. The molecular weight of CMCase was estimated to be 42 kDa by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. The maximum activity of the purified CMCase was observed at pH 6.0 and $30^{\circ}C$, and stable for pH 4 to 7 to maintain 40% activity. The CMCase activity was activated by $Al_{2}(SO_{4})_{3}$, and inhibited by SDS. Also, the enzyme activity was decreased by the addition of ethylene diamine tetraacetic acid (EDTA), suggesting that the purified CMCase is metalloenzyme.

• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2034-2042
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• 2015

A one-pot process of enzymatic synthesis of deoxythymidine-5'-triphosphate (5'-dTTP) employing whole cells of recombinant Escherichia coli coexpressing thymidylate kinase (TMKase) and acetate kinase (ACKase) was developed. Genes tmk and ack from E. coli were cloned and inserted into pET28a(+), and then transduced into E. coli BL21 (DE3) to form recombinant strain pTA in which TMKase and ACKase were simultaneously overexpressed. It was found that the relative residual specific activities of TMKase and ACKase, in pTA pretreated with 20 mM ethylene diamine tetraacetic acid (EDTA) at 25℃ for 30 min, were 94% and 96%, respectively. The yield of 5'-dTTP reached above 94% from 5 mM deoxythymidine 5'-monophosphate (5'-dTMP) and 15 mM acetyl phosphate catalyzed with intact cells of pTA pretreated with EDTA. The process was so effective that only 0.125 mM adenosine-5'-triphosphate was sufficient to deliver the phosphate group from acetyl phosphate to dTMP and dTDP.

• The Korean Journal of Mycology
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• v.33 no.2
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• pp.75-80
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• 2005

A carboxymethyl cellulase (CMCase) has been purified from Loweporus roseoalbus. The molecular weight of the purified CMCase was estimated to be 28.5 kDa by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis. The maximum activity of the purified CMCase was observed at pH 4.0 and $30^{\circ}C$, and stable for pH 3 to 5 to maintain 60% activity. The CMCase activity was activated by SDS and inhibited by PMSF and 1,10-phenanthroline. The enzyme activity was also decreased by the addition of ethylene diamine tetraacetic acid (EDTA), suggesting that the purified CMCase is metalloenzyme.