• Biotechnology and Bioprocess Engineering:BBE
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• v.2 no.2
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• pp.109-112
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• 1997

Morphology of carbonate crystals grown on the surface of artificial cell membranes was controlled by changing the interfacial chemistry. For octadecyltriethoxysilane (OTE) films with terminal methyl groups interacting little with an aqueous calcium carbonate solution calcite (104) crystals were formed. Polymerized pentacosadiynoic acid (PDA) films with terminal carboxylic acid groups induced deposition of calcite (012) crystals aligned along with each other within a polymer domain. On the other hand, stearyl alcohol (StOH) films with terminal hydroxyl groups induced deposition of aragonite crystals. When PDA was mixed with StOH, the 8:1 PDA:StOH (molar ratio) film produced dominating calcite (012) crystals without any crystal alignment, and the 4:1 mixture film produced minor calcite (012) crystals and major aragonite crystals. For the 2:1, 1:1, 1:2, and 1:4 mixture films, aragonite crystals were dominating. Hence, it is found that the chemical composition at the interface plays a very important role in controlling the morphology of deposited carbonate crystals.

• Journal of the Korean institute of surface engineering
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• v.31 no.1
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• pp.3-11
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• 1998

Molten Carbonate Fuel cell is a promising new type electric power generation system which can achieve high efficiency, lower matrrial cost and high operating temperature Making internal reforming possible. Although the development of the MCEC is progressing rapidly toward commercialization, two important tchological problems such as dissolution of NiO cathode and not corrosion of metallic separator plate must be resolved. Because MCFC is operated at $650^{\circ}C$ and the electrolyte is very corrosive, corrosion-resistance of separator plated against oxidation abd molten carbonate is required. Al-coating on separator material for corrosion-resistance was carried out by painting, thermal spraying. hot dipping and vacuum vapour deposition. The corrosion of Al-coated STS 316S and 316L in molten carbonate at $700^{\circ}C$was studied. Vacuum vapour deposition and thermal spraing for Al-coating on STS 310S and 316L were the most effective methods for protecting thestainless steel corrosion in molten carbonate.

• Transactions on Electrical and Electronic Materials
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• v.8 no.6
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• pp.283-285
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• 2007

The molten carbonate fuel cell has conspicuous feature and high potential in being used as an energy converter of various fuel to electricity and heat. However, the molten carbonate fuel cell which use strongly corrosive molten carbonate at $650^{\circ}C$ have many problem. Systematic investigation on corrosion behavior of stainless steels has been done 62 mole% $Li_2CO_3$ and 38 mole% $K_2CO_3$ melt at 923 K by using steady-state polarization method and electrochemical impedance spectroscopy method. It was found that SUS 310L and Al coating specimen may be the best choice among the alloys tested in this study for molten carbonate fuel cell component material.

• Corrosion Science and Technology
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• v.7 no.1
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• pp.22-26
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• 2008

Formation of protective iron carbonate films in $CO_2$ corrosion can reduce corrosion rate substantially and the effects have been incorporated in various prediction models. The $CO_2$ corrosion with the presence of free acetic acid is known to increase corrosion rate below scaling temperature. The possible interaction between the formation of iron acetate and iron carbonate films can affect the protectiveness of the film. The study is done using 3% NaCl solution under stagnant $CO_2$ -saturated condition at the scaling temperatures at various pH values and HAC concentrations. The result show that the presence of HAc does not affect the formation of protective iron carbonate film but delays the attainment of protective iron carbonate due to a possibility of solubilising of ferrous ions and thinning of the films.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.311-312
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• 2005

The precipitation of U(VI) in the presence of phosphate and carbonate was investigated in the pH range of 4 to 13 and the following was obtained as a result of this experimental condition. U(VI) precipitates as a $NaUO_{2}PO_{4}$ at pH<9 but as mixtures of phosphate, hydroxides and/or carbonate at pH>9. The portion of the phosphate in the precipitate decreases almost linearly to near zero with an increasing pH in the range of 9 to 13. The U(VI) phosphate is dissolved by the carbonate complex formation at pH<10.5. The ternary complex of a carbonate and phosphate is not found.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.105-108
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• 2011

The cycling behavior of $Li_4Ti_5O_{12}$ electrode in the ionic liquid (IL)-based electrolytes containing 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide and a small amount of additive (vinylene carbonate, ethylene carbonate, fluoroethylene carbonate) was investigated. The $Li_4Ti_5O_{12}$ electrode in the IL electrolyte with an additive exhibited reversible cycling behavior with good capacity retention. Electrochemical impedance spectroscopy and FTIR studies revealed that an electrochemically stable solid electrolyte interphase was formed on the $Li_4Ti_5O_{12}$ electrode in the presence of vinylene carbonate and ethylene carbonate during cycling.

• Journal of the Korean Ceramic Society
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• v.52 no.5
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• pp.350-355
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• 2015

To develop ceramic composite anodes of solid oxide fuel cells without metal catalysts, a small amount of barium carbonate was added to an $(La_{0.8}Sr_{0.2})(Cr_{0.5}Mn_{0.5})O_3(LSCM)$ - YSZ ceramic composite anode and its catalytic effects on the electrode performance were investigated. A barium precursor solution with citric acid was used to synthesize the barium carbonate during ignition, while a barium precursor solution without citric acid was used to create hydrated barium hydroxide. The addition of barium carbonate to the ceramic composite anode caused stable fuel cell performance at 1073 K; this performance was higher than that of a fuel cell with $CeO_2$ catalyst; however, the addition of hydrated barium hydroxide to the ceramic composite anode caused poor stability of the fuel cell performance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.11
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• pp.1000-1003
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• 2007

The molten carbonate fuel cell has conspicuous feature and high potential in being used as an energy converter of various fuel to electricity and heat. However, the molten carbonate fuel cell which use strongly corrosive molten carbonate at $650^{\circ}C$ have many problem. One of the material problems is the severe corrosion of the metallic components, such as the separator. The effect of coating and annealing treatment on the corrosion for SUS 304 and SUS 430 which are the candidate materials for molten carbonate fuel cell hardware has been investigated in molten carbonate at $650^{\circ}C$ by using steady state polarization and electrochemical impedance spectroscopy method. It was found that the corrosion current of these SUS 304 and SUS 430 decreased with coating and annealing treatment.

• Bulletin of the Korean Chemical Society
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• v.22 no.5
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• pp.481-487
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• 2001

Surface films formed prior to bulk reduction of lithium have been studied at gold, platinum, and copper electrodes in rigorously dried propylene carbonate solutions using electrochemical quartz crystal microbalance (EQCM) and secondary ion mass spectrometry experiments. The results indicate that the passive film formation takes place at a potential as positive as about 2.0 V vs. Li/Li+ , and the passive film thus formed in this potential region is thicker than a monolayer. Quantitative analysis of the EQCM results indicates that electrogenerated lithium reacts with solvent molecules to produce a passive film consisting of lithium carbonate and other compounds of larger molecular weights. The presence of lithium carbonate is verified by SIMS, whereas the lithium compounds of low molecular weights, including lithium hydroxide and oxide, are not detected. Further lithium reduction takes place underneath the passive film at potentials lower than 1.2 V with a voltammetric current peak at about 0.6 V.

• Elastomers and Composites
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• v.5 no.1
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• pp.69-74
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• 1970

The influence of various calcium carbonate on the physical properties of natural rubber have teen carries out extensive experiments on compounding. Final evaluation was made through various kinds of physical test-tensile strength, modulus, tear strength and hardnees-including particle size. The results are as follows: 1. Generally, tile tensile strength, modulus and tear strength showed the similar tendency in various calcium carbonate compounding. 2. The maximum volume of general using have been obtained with 150 phr calcium carbonate in $NR-CaCO_3$ compounding. 3. The particle size of domestic calcium carbonate showed $1.0\mu-2.6\mu$.