• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.2109-2112
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• 2011

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2805-2808
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• 2011

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.309-312
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• 2012

• Elastomers and Composites
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• v.40 no.1
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• pp.53-58
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• 2005

Carbon tetrachloride is very reactive chain transfer agent due to the resonance stability of the trichlorocarbon radicals after breaking of C-Cl bond. Effect of benzylic radical comparing to trichlorocarbon radicals in the chain tranrfer reactions was investigated. From the structural point of view, cumyl chloride is a good candidate because it has the C-Cl bond with benzylic radicals after displacement of C-Ci bond. The reactivity of free radical polymerization of styrene in the presence of cumyl chloride was compared with that of carbon tetrachloride by calculating chain transfer constants. Results show that the cumyl chloride acts as a stronger chain transfer agent than carbon tetrachloride. The calculated chain transfer constant of cumyl chloride shows higher value (0.0463) than that of carbon tetrachloride (0.0011) in the styrene polymerization. High reactivity of cumyl chloride comparing to that of carbon tetrachloride is probably due to the higher resonance stability or benzylic radical than that or trichlorocarbon radicals after breaking of C-Cl bond. Monte Carlo simulation method is applied for characterizing the validity of kinetic constants according to the ratio of chain transfer agent to monomer.

• Analytical Science and Technology
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• v.10 no.6
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• pp.453-458
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• 1997

Many polymeric poly(vinyl chloride) membrane electrodes have been developed for the determination of basic drugs. But relatively little has been roported concerning the behavior of ligand free PVC memebranes. In connection with the evaluation of various ionophores, we bave evaluated a near-Nernstian response and selectivity of these ligand-free PVC electrodes towards basic drugs such as alverine, chlorpromazine and promazine. The electrode membranes were constructed with only several plasticizer and poly (vinyl chloride) matrix. The plasticizer studied were dioctyl phenylphosphonate, 2-nitrophenyl octyl ether, isododecyl phenylphosphate and dioctyl maleate.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.787-792
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• 2001

The chloride ion penetrating into concrete is classified as the fixed chloride ion being bound in reacting to cement hydrate and the free chloride ion having a direct effect on rebar corrosion because being in solution inside porosity of concrete. Therefore, in order to study the diffusion properties of chloride ion, it is needed to evaluate binding chloride ion in concrete. In this study, we tried to give a fundamental information on diffusion of chloride ion in concrete with mineral admixtures through analysis of micro-structure transformations in concrete and effects on binding of chloride ion in cement paste when mixed with fly-ash, blast furnace slag, silica fume etc. which are used to improve durability and permeability of concrete

• Bulletin of the Korean Chemical Society
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• v.24 no.7
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• pp.1021-1022
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• 2003

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.553-557
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• 2022

The present study evaluate the chloride extracion under electrochemical chloride extraction method. Chloride was penetrated into the concrete from external reservoir using a 4M NaCl solution, and an electrochemical chloride extraction method was applied after the curing period of 1 year. The current density was constantly kept 1000 mA/m² for coulostatic application with the variation in potential difference. The duration of the ECE treatment was 2, 4, 8 weeks, respectively. The residual chloride concentration at all depths decreased, and the chloride concentration decreased as the application period increased. After the application period of 8 weeks, 62.9 to 77.6 % of chloride extracted in the total chloride profile, and 77.7 to 99.5 % of chloride extracted in the free chloride profile. In particular, the concentration of free chloride at a depth of 7 mm or more from the concrete surface was 0.01 % or less by cement. In addition, it was confirmed that the bound chloride could be extracted by the electrochemical chloride extraction.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.10a
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• pp.87-92
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• 1994

The main objective of this study is to determine the critical chloride ion concentrations in the pore solutions causing depassivation of steel reinforcement in concrete made with cements of different $C_3A$ contents. Cement pastes with water-ratio of 0.5 were prepared using four cements with $C_3A$ contents of 0.46, 5.97, 9.14, and 9.65 percent. The pastes were allowed to hydrate in sealed containers for 28days and then objected to pore solution expression. The expressed pore fluids were analyzed for chloride and hydroxyl ion concentrations. It was found that the free cholride concentration in the pore solution decreases significantly with an increase in the $C_3A$ content of the cement. With increasing level of chloride addition, although the alsolute amount of bound chloride increase, the ratio of bound to total chlorides decreases.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.3
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• pp.287-298
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• 1995

This study was undertaken to examine the effect of salting in 10% salt solution added 2% calcium chloride on the kimchi fermentation. The addition of calcium chloride extended edible periods of the Kimchi to 4~5 days and increased relatively the hardness of Chinese Cabbage. In the addition of calcium chloride, the activities of amylase and $\beta$ -galactosidase were not high during all periods fermentation. Polygalacturonase and protease activities were low 2~21%, 2~26% all periods fermentation, respectively. There were significant correlations between the delay of ripeness and decreasing enzyme activation. The amount of free amino acid by the treatment with calcium chloride was decreased of 10~16% at the late of fermentation than that of control. the treatment with calcium chloride of the Kimchi was increased hardness, but decreased cohesiveness and gumminess was during all periods fermentation. the adhesiveness was increased at the early of fermentation but decreased at the late of fermentation.