• Analytical Science and Technology
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• v.11 no.4
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• pp.235-242
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• 1998

Membrane electrode based on chitin(po1y-[$1{\rightarrow}4$]-${\beta}$-N-acetyl-D-glucosamine) was prepared by mixing uniformly grounded of chitin (100 mesh) with PVC and DOS. We investigated the potential response of chitin membrane electrode to metal ions. It was observed that the response slopes for $Cd^{2+}$(34.9 mV/decade) and $Cu^{2+}$(34.0 mV/decade) were larger than those for other ions in pH 4 acetate buffer. The potentiometric response of chitin electrode to varying pH was nearly constant in the pH range of 2~12.

• Korean Journal of Materials Research
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• v.5 no.8
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• pp.905-912
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• 1995

Influences of the starting salts on the phase and morphology of the Pb(Zr, T)O$_3$powders prepared by ultrasonic spray pyrolysis were studied. The Phases of the Powders Prepared from the combination of metal nitrate(or oxynitrate), acetate(or oxyacetate), and alkoxide were the Pb(Zr, Ti)O$_3$with or without minor PbTiO$_3$. The pores on the surface of the spherical particles increased with the nitrate content in the starting solution and their formation was thought to result from the decomposition characteristics of metal nitrate. Pb acetate, Zr oxyacetate, Ti oxynitrate, and Ti (isopropoxide+acetylacetonate) was suitable as the starting salts for the preparation of Pb(Zr, Ti)O$_3$powders by ultrasonic spray pyrolysis in the viewpoint of the phase and morphology of the powders.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.83-84
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• 2014

This study evaluated the effectiveness of biostimulating agent in contaminated coastal sediment. The study was conducted via column tests in coastal sea wherein two separate columns were employed for two different polymers used and another column for a blank. The biostimulating agent was made by mixing sea sediment with biostimulants viz acetate, nitrate, sulfate. The biostimulating agent was then rolled into balls, dried and coated with either Cellulose Acetate (CA) or Polysulfone (PS) to control the release of the biostimulants. The pH was around 7.6~8 for 4 months while COD, TP and TN were significantly lower in the column containing biostimulating agents. Heavy metal(Fe, Zn, Cd, Cr, Pb, Cu) was converted to stable forms and PS coated biostimulating agent had a high efficiency of heavy metals distribution.

• Journal of the Korean Chemical Society
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• v.43 no.5
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• pp.511-516
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• 1999

Shiff Base ligand such as [NOIPH] have been synthesized from 2-hydroxy-1-naphthaldehyde and arometic amine. Co(II), Ni(II), and Cu(II) complexes from the reaction metal salts with Tridentate Schiff Base [NOIPH] were sythesized. The ligand and metal(II) complexes were characterized by the elementary analysis, IR, UV-Vis, NMR spectra, and thermogravimetric analysis. Metal(II) complexes in solid state have been shown that the mole raio of Schiff base [NOIPH] as $N_2O$ type to Metal(II) is 2:1 and the metal(II) complexes of $N_2O$ ligand type were four-coordinated configuration.

• Journal of the Korean Applied Science and Technology
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• v.7 no.1
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• pp.71-76
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• 1990

Transesterification reactions (methyl methacrylate with monoethanolamine, methyl methacrylate with n-butyl alcohol, dimethylphthalate with ethylene glycol, dimethyl phthalate with monoethanolamine) were kinetically investigated in the presense of various metal acetate catalysts at $110^{\circ}C$. The amount of reactants was measured by gas and liquid chromatography, and the reaction rates also measured from the amount of reaction products and reactants upon each catalyst. The transesterification reactions were carried out under the first order conditions respect to the concentration of reactants, respectively. The overall reaction order was 2nd, Maximum reaction rates were appeared at the range of 1.4 to 1.6 in electronegativity of metal ions and maximum catalytic activities were obserbed at the range of 1.5 to 1,8 in instability constant of metal acetates.

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.67-71
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• 1987

The transesterification reaction between diethanolamine and methyl methacrylate was kinetically investigated in the presence of various metal acetate catalysts at $120^{\circ}C$. The amount of reacted methyl methacrylate was measured by gas chromatography and liquid chromatography, and the reaction rate also measured from the amount of reaction products and reactants under each catalyst. The transesterification reaction was carried out in the first order with respect to the concentration of diethanolamine and methyl methacrylate, respectively. The over-all order is 2nd. The apparent rate constant was found to obey first-order kinetics with respect to the concentration of catalyst. The maximum reaction rate was appeared at the range of 1.4 to 1.6 of electronegativity of metal ions and instability constant of metal acetates.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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• pp.130-131
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• 2016

Although many metals contaminated sediment from coastal area contain both anionic and cationic heavy metals, the current remediation technologies are not effective for stabilize heavy metals of both anionic and cationic elements from contaminated coastal region. the present work investigated the efficiency and mechanism of immobilization of Fe, Zn, Cr, Cu, Pb and Cd metal solutions in modified zeolite based biostimulant ball. Biostimulant ball containing acetate, nitrate and sulphate which are enhance the activity of marine microorganisms and it can act as electron donors and electron acceptors. Modified zeolite and chelating agent is greatly enhance the metal stabilization due to increased immobility of the analysed metals. The XRD, FT-IR and SEM of modified zeolite which cheating agents containing heavy metals were investigated. The results indicated that heavy metals could be effectively immobilized in modified zeolite and chelating agents in BSB added sediment. The immobilization of heavy metals in modified zeolite and chelating agents along with BSB could be due to stabilize of heavy metal cations. Immobilization of heavy metals using BSB with modified zeolite and chelating agent has lower cost effect and enhance the sediment quality.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.815-820
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• 2011

Three kinds of organometallic compounds (chromium acetylacetonate, magnesium acetate and vanadyl acetylacetonate) were used as transition metal precursor, titanium n-butoxide and multi-walled carbon nanotube as titanium and carbon precursor to prepare metal oxide-CNT/$TiO^2$ composites. The surface properties and morphology of metal oxide-CNT/$TiO^2$ composites were by Brauer-Emett-Teller (BET) surface area measurement, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) analysis. The photocatalytic activity of prepared metal oxide-CNT/$TiO^2$ composites was determined by the degradation effect of methylene blue in an aqueous solution under irradiation of visible light.

• Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.18-25
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• 2010

Interest in plant-derived food additives has increased recently, with efforts to identify natural antioxidant sources to replace synthetic antioxidants. This study evaluated the antioxidant effects of organic solvent fractions of 80% methanol extracts from Pediastrum duplex and Dactylococcopsis fascicularis microalgae. Among the solvent fractions tested, the ethyl acetate and n-hexane fractions from P duplex effectively scavenged 79.8% and 74.5% of DPPH free radicals, respectively. The chloroform fraction from D. fascicularis showed the strongest $H_2O_2$ scavenging ability (49.7%). The greatest scavenging of hydroxyl radicals (73.1%) was exhibited by the 80% methanol extract from P duplex. Aqueous residue and ethyl acetate fraction from P duplex provided the strongest nitric oxide scavenging (57.7%) and metal chelating effect (82.1%), respectively. Chloroform and ethyl acetate fractions from P duplex and n-hexane fraction from D. fascicularis exhibited significantly greater inhibition of lipid peroxidation than the commercial antioxidants. These results suggested that P duplex and D. fascicularis microalgae having potential anti oxidative compounds with various properties could be utilized in the food and pharmaceutical industries.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.253-253
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• 2009

Electrospinning is one of the simple, cost- efficient methods to produce long continuous semiconducting oxide nanofibers. Polyvinyl Alcohol (PVA) and zinc acetate were used. PVA/Zinc acetate aqueous solutions were electrospun into nonwoven webs. CCD camera, with a lens of long working distance and digital video board were used in capturing the drop and web deposition. The diameter and morphology of nanofibers were analyzed with a Field-emission scanning electron microscopy (FE-SEM). In this study, the average diameter and morphology of nanofibers have been explorered.