• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.1081-1090
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• 2003

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.281-284
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• 1999

Bridge structure is known as one of important infrafacilities for comfortable human life. Recent long-span bridges, such as Kwang-Ahn Grand bridge, S대-Hae Grand Bridge, Young-Jong Grand Bridge, etc, have been designed and constructed near the seaside without in-depth consideration of concrete durability problems, It is in particular noted that corrosion of reinforcement steel in concrete is very important for the durability enhancement of concrete structures. The objective of this experimental study is to investigate the corrosion degree of reinforcing steels in concrete specimens which are exposed to cyclic wet and dry saltwaters, and then to develop pertinent corrosion protection system such as rational cover depth, corrosion inhibitors, cathodic system for reinforced concrete bridges exposed to marine environment.

• 한국환경과학회지
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• 제18권2호
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• pp.187-195
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• 2009

This study was investigated to control the corrosion and scale at the cooling water system in steel works. Laboratory and field tests were performed for the indirect cooling water system of plate mill. Throughout the experiment, various factors such as leakage of pipes, heating rate and capacity, and the reaction between existing and substitute inhibitors were carefully monitored. The results showed that the harmful effect of high temperature could be minimized, and satisfactory corrosion/scale controls were effectively achieved using inhibitor, even at the increased temperature of $80^{\circ}C$. The batch and field tests in the gas scrubbing cooling water system of blast furnace and cooling water system of corex plant indicated that the new inhibitor was more effective for the prevention of corrosion and scale than the existing one.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.254-257
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• 2006

Five bench scale specimens were used to evaluate corrosion performance of damaged epoxy-coated bars in chloride contaminated concrete. The test specimens were subjected 48 weekly cycles of ponding with sodium chloride solution and drying. Test results using linear polarization technique show that the current density of specimen with conventional steel becomes $0.715\;{\mu}A/cm^2$ indicating that the steel bars are in moderate or high corrosion condition. However, the corrosion rates of the specimens with damaged epoxy coated bars are much below $0.1\;{\mu}A/cm^2$ and the bars appears to be in passive condition. The corrosion protection performance provided by calcium nitrite is better than that of specimens with the other two inhibitors.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.659-662
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• 2005

Electrochemical impedance spectroscopy (EIS) has been extensively used to try to evaluate the corrosion state of the steel/concrete system. This technique is attractive because, in theory, used in a wide range of frequencies, it can give detailed information about the mechanisms and kinetics of the electrochemical reactions. Impedance measurements were performed using potential control and measuring the corresponding current response. One-year-old southern exposure test. specimens were used in the current study. The effectiveness of corrosion inhibiting additives was evaluated. The corrosion current densities estimated by impedance measurements were confirmed by those determined using linear polarization techniques. The purpose of this study was to evaluate the long-term-performance potential of the corrosion inhibitors in chloride contaminated reinforce concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.827-832
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• 2000

Bridge structure is known as one of important infrafacilities for comfortable human life. Recent long-span bridges, such as Kwang-Ahn Grand bridge, Seo-hae Grand Bridge, Young-Jong Grand Bridge, etc, have been designed and constructed near the seaside without in-depth consideration of concrete durability problem. It is in particular noted tat corrosion of reinforcement steel in concrete is very important for the durability enhancement of concrete structures. The objective of this experimental study is to investigate the corrosion behavior of reinforcing steels in concrete specimens which are exposed to cyclic wet and dry saltwaters, and then to develop pertinent corrosion protection system such as rational cover depth, corrosion inhibitors, cathodic system for reinforced bridges exposed to marine environment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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• pp.265-271
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• 1997

Marine concrete structures have been exposed to salt from ocean environments. Chloride-penetration into marine concrete structures should accelerate the corrosion of reinforcement steel, which may severely affect the durability of them. Major concerns are to develop durable concrete for high corrosion resistance of reinforcing steel embedded in concrete. The objective of this experimental study is to investigate adequate usage of corrosion inhibitors by evaluating corrosion level in 80 specimen located in the labatory and in the site. 80 specimen of cube 20${\times}$20${\times}$11.5 and 63 specimen of slab 30${\times}$30${\times}$10 are made for this study.

• 한국표면공학회지
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• 제32권3호
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• pp.377-384
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• 1999

The corrosion of copper in $H_2$$SO_4$ $-H_2$$O_2$ etching solutions with amines was investigated at various flow rates (v). Amine additives give a retardation of $H_2$$O_2$ decompositions, increases in both corrosion rates and etch factor, and a protection of etched copper surfaces. However n-alkylamine additives acted as corrosion inhibitors at v < 10cm/s, those acted as corrosion accelerators at v of 10-220cm/s. The maximum corrosion rate was obtained with about 0.1 molal concentration of additives. Steric effects of substituted groups suppressed the acceleration of copper corrosion. The increases in both corrosion rates and flow rates gave the increase in etch factor. Corrosion rates with n-alkylamine increased in the order of ethylamine < n-propylamine < n-butylamine, those with butylamine isomers tert- < sec- < iso- < n-butylamine, and those with amine additives of different number of substituted groups tri- < di- < mono-n-propylamine, respectively.

• 한국표면공학회지
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• 제56권2호
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• pp.125-136
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• 2023

Recently, ammonia has emerged as an alternative energy source that can reduce carbon emissions in various industries. Ammonia is used as a fuel in internal combustion engines because it contains no carbon in its components and does not emit any carbon when burned. It is also used in various fields such as fertilizer production, refrigeration, cleaning and disinfection, and drug manufacturing due to its unique characteristics, such as high volatility and easy solubility in water. However, it is highly corrosive to metals and is a toxic gas that can pose a risk to human health, so caution must be exercised when using it. In particular, stress corrosion cracking may occur in containers or manufacturing facilities made of carbon-manganese steel or nickel steel, so special care is needed. As ammonia has emerged as an alternative fuel for reducing carbon emissions, there is a need for a rapid response. Therefore, based on a deep understanding of the causes and mechanisms of ammonia corrosion, it is important to develop new corrosion inhibitors, improve corrosion monitoring and prediction systems, and study corrosion prevention design.

• Journal of Electrochemical Science and Technology
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• 제4권2호
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• pp.81-87
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• 2013

Inhibition of corrosion of mild steel in sulphuric acid by acidic extract of Jatropha Curcas leaves has been studied using weight loss and thermometric measurements. It was found that the leaves extract act as a good corrosion inhibitor for mild steel in all concentrations of the extract. The inhibition action depends on the concentration of the Jatropha Curcas leaves extract in the acid solution. Results for weight loss and thermometric measurements indicate that inhibition efficiency increase with increasing inhibitor concentration. The adsorption of Jatropha curcas leaves extract on the surface of the mild steel specimens obeys Langmuir adsorption isotherm. Based on the results, Jatropha curcas leaves extract is recommended for use in industries as a replacement for toxic chemical inhibitors.