• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.133-134
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• 1998

• Journal of the Korean institute of surface engineering
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• v.26 no.3
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• pp.135-142
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• 1993

탄소강 및 Nickel 음극에서 아연의 전착특성에 대하여 조사하였다. 황산아연 및 염화아연용액속에서 회전전극을 사용하여 실험한 결과 아연의 평형전위 이전에서 전착이 일어나는 소위 Underpotential Deposition 현상이 관찰되었다. 또한 이렇게 전착이 일어난 아연층은 평형상태에서 일정한 두께로 제한되는데 전착전압에 따른 전착층의 전하량을 계산한 결과 다층흡착구조과 유사한 경향을 나타내었다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.773-776
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• 2008

The corrosion of steel in concrete is significant in marine environment. Marine bridges are readily deteriorated due to the exposure to marine environment. Salt damage is one of the most detrimental causes to concrete bridges and port structures. Especially, the splash and tidal zones around water line are comparatively important in terms of safety and life-time point of view. During the last several decades, cathodic protection (cp) has been commonly accepted as an effective technique for corrosion control in concrete structures. Zn-mesh sacrificial anode has been recently developed and started to apply to the bridge column cp in marine condition. The detailed parameters regarding Zn-mesh cp technique, however, have not well understood. This study is to investigate how much Zn-mesh cp influences along the concrete column at elevated temperature. About 100cm column specimens with eight of 10cm segment rebars have been used to measure the variation of cp potential with the distance from Zn-mesh anode at both 10$^{\circ}$C and 40$^{\circ}$C in natural seawater. The cp potential change and current diminishment along the column specimens have been discussed for the optimum design of cp by Zn-mesh sacrificial anode

• Journal of the Microelectronics and Packaging Society
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• v.15 no.1
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• pp.45-50
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• 2008

The effects of electrolytes and additives on the electropolishing of 50 and $20{\mu}m$ diameter copper via were investigated to flatten 3D SiP through via. The termination time was determined with analysis of applied potential on anode and cathode to avoid excess electropolishing. Acetic acid played a role of accelerator and glycerol played a role of inhibitor in phosphoric acid electrolytes. The overplated copper on the through via was effectively electropolished in the phosphoric electrolytes with acetic acid and glycerol addition. The electropolishing was terminated at the point of abrupt change of applied potential to remove only overplated copper on the through via.

• Journal of the Korean Chemical Society
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• v.21 no.4
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• pp.276-283
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• 1977

Reduction of dichromate at a platinum cathode in acid solution was studied by cyclic voltammetry and controlled potential electrolysis. Cathodic polarization curve consisted of three waves in unbuffered solution of potassium dichromate having initial pH ranges 1.5∼4.0, with sodium sulfate as the supporting electrolyte. Relative heights of the first and the second waves were, respectively, a function of chromium (Ⅵ) concentration and activity of hydrogen ion, but that of the third wave was not proportional to both of them. The current of the first two peaks were proportional to the sweep rate of potential (${\nu}$), while that of the last peak vs. ${\nu}^{1/2}$ was linear at the sweep rate of less than 50mV/sec. By the controlled potential electrolysis, the reduction of chromium (Ⅵ) was almost completely suppressed at potentials more negative than the last peak and at initial pH's above ca. 2.3 of unbuffered solution. Therefore, these peaks represented, respectively, $Cr_2O_7^{2-}{\to}Cr^{3+},\;2H^+{\to}H_2$ and the formation of a cathodic film.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.363-368
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• 2024

Steel structures used in marine environments, such as ships, offshore structures or sub-structures in wind power generation facilities are prone to corrosion. In this study, the corrosion fatigue crack propagation characteristics due to the environmental load are examined by experiment at -1050 mV vs. SCE, which is equivalent to the anti-corrosion potential of zinc anodes that are widely used as sacrificial anodes. In this study, for this purpose, an experimental study is conducted on the effect of cathodic protection on the propagation of fatigue cracks in the seawater environment under the condition of -1050 mV vs. SCE, considering the wave period in synthetic seawater. Cathodic protection prevents corrosion; however, excessive protection generates hydrogen through chemical reactions as well as calcareous deposits. The fatigue crack propagation rate appeared to be faster than the rate in a seawater corrosion environment at the early stages of the experiment. As the crack length and stress intensity factor K increased, the crack propagation rate became slower than the fatigue crack propagation rate in seawater. However, the crack growth rate was faster than that in the atmosphere.

• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.74-79
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• 2016

The effects of scale formation of hardness material caused by electrode reactions on the desalination performance of the membrane capacitive deionization (MCDI) were investigated. During the repeated adsorption and desorption process for the influent containing $Ca^{2+}$ ion, changes in effluent concentration and cell potential with respect to the number of adsorption were analyzed. It was found that $OH^-$ generation at the cathode was initiated at about 0.8 V or more of cell potential. In addition, the scale of $Ca(OH)_2$ was formed on the surface of cathode carbon electrode by combining adsorbed $Ca^{2+}$ ions and $OH^-$ ions generated from electrode reaction. As the scale was forming, the electrical resistance of carbon electrode was increasing, which resulted in the decrease of the adsorption amount. In the case of the operation at 1.5 V cell potential, the adsorption was reduced to 58% of the initial adsorption amount due to the scale formation.

• Analytical Science and Technology
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• v.5 no.4
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• pp.417-423
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• 1992

The effects of metal ions on the arsenic(III) stripping peak were examined by the cathodic stripping voltammetry. The reduction stripping peak potential and current of arsenic(III) value were -0.79V(vs. Ag/AgCl). $0.86{\mu}A$ by using 0.1N-hydrochloric acid solution. When 10 times of Cu(II) was added to the solution, the reduction stripping peak potential of arsenic(III) was the value of -0.84V(vs. Ag/Cl), which showed a good agreement with theoretical value -0.84V(vs. Ag/Cl) by using 0.1N hydrochloric acid solution. Lead(II) and copper(II) increased the stripping peak heigh of arsenic(III), Among them, the copper(II) extremely enhanced it.

• Journal of the Korean Institute of Gas
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• v.2 no.1
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• pp.40-46
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• 1998

Mathematical modeling on the corrosion of the steel casing and main pipe due to the protection current resulting from a cathodic protection system was carried out using boundary element method. The model is consisted of Laplace's equation with non-linear boundary conditions(Tafel equations) and the iterative technique to determine the miexed potential of the steel casing. The model is applied to the normal steel casing section as well as abnormal one with defects such as metal touch and insulation defects. From the modeling procedure, we can calculate the potential distributions and current density distributions of the system. The theoretical results of the qualitatiive corrosion aspect along the steel casing and main pipe agree well with the experimental results within the experimental conditions studied.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.607-612
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• 2021

Silicon (Si) is one of the promising active materials to replace the widely used graphite because of its low electrochemical potential and high theoretical capacity. However, Si anodes still face in problems with the huge volume expansion and continuous decomposition of the electrolyte during repeated charge and discharge processes. To address these issues, a cross-linkable waterborne polyurethane (CWPU) based on a bio-oil, castor oil, was prepared and reacted with Tris(2,3-epoxypropyl) isocyanurate (TGIC) linkers, resulting in the formation of a mechanically robust 3D network structure. Si anodes fabricated with the CWPU-TGIC exhibited stable cycling performances and excellent discharge capacities. The results revealed that the CWPU-TGIC binder efficiently accommodates the large volume change for Si anode during charge and discharge cycles. Overall, the eco-friendly binder shows great promise in improving the electrochemical performances of Si anodes.