• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.5
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• pp.548-557
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• 2015

This paper is results on Chemisorption of organic compound for the sea water fire fighting line of naval vessels. The quantitative analysis of Chemisorption has been investigated in seawater after immersion in 0.1 % of NaDDTC solutions for 43 hours. The morphology and topography were investigated by FE-SEM and AFM. The chemical elements were analyzed by SEM-EDS, XPS and the depth of chemical elements was measured by depth profiles. The effect of NaDDTC comes from Chemisorption between Copper and Sulfur of NaDDTC. As a result, test results showed that sulfur is helpful to protect a corrosion of seawater line.

• Journal of Radiation Protection and Research
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• v.31 no.2
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• pp.105-113
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• 2006

The oxidizing species are generated from the radiolysis of groundwater in the pore of buffer material around the canister used for the disposal of spent fuels. A mathematical model was introduced to calculate the cathodic current density induced by the oxidant around the canister, which determined the corrosion of carbon steel. An analytical solution was derived to get the cathodic current density in the cylindrical coordinate. The cathodic current densities from both the rectangular coordinate and cylindrical coordinate were compared with each other. The source terms and absorbed dose rate for the calculation of the radiolysis were calculated using the ORIGEN2 and MCNP computer code, respectively. The radius of the canister was determined with the new model in order to prevent the local corrosion. The results showed that the new solution made the cathodic current density around 25 % lower than the Marsh model.

• Journal of Conservation Science
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• v.30 no.2
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• pp.157-168
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• 2014

This study, by selecting 3 kinds(Polish T, H, C) of metal polish being frequently used for silver archival objects treatment at present, a polish having excellent conservative property that minimizes damage of silver surface while effectively removing its yellow discolored layer by each using tool was intended to be discovered by comparing performance of tarnish inhibitor, corrosion inhibitor contained in each polish. As a result of analysis, it was confirmed that specimen that was cleaned with cotton swab and lint-free wipe by using Polish C provides not only uniformed surface expression and minimum damage but also removal function of corrosion layer. In addition, even though tarnish inhibition film should be formed after polish treatment, discolored phenomenon is unable to be prevented but among those polishes, Polish C was represented to be most stable against UV and yellowing and it showed relatively better features than that of Polish H and T in terms of hydrophobic, dispersive property. Through this, it is confirmed that Polish C would show the most excellent performance among polishes being used for conserving silver archival objects.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.42-43
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• 2005

본 연구에서는 Cu 슬러리에 부식방지제인 BTA를 첨가하여 슬러리내의 과수의 농도, pH 의 변화, 연마입자의 종류에 따라 연마거동에 미치는 영향과 각 chemical 변화에 따른 Cu surface의 변화를 살펴보았다. BTA (Benzotriazole, $C_6H_4C_3H$)를 첨가함으로써 본 연구에서 시행된 pH 와 과수의 변화에 상관없이 Cu-BTA film을 형성하여 Cu의 dissolution을 최대한 억제하는 것을 확인할 수 있었다. 또 그로인해 BTA를 첨가하지 않았을 때보다 얇은 passivation layer를 형성함을 알 수 있었고 contact angle도 더 높았다. 연마율의 경우에도 BTA가 첨가됨으로써 감소됨을 확인할 수 있었고 연마입자로 alumina particle을 사용한 경우에는 pH6, 과수 10vol%이상에서는 오히려 연마율이 증가하였다. fumed silica의 경우에는 hardness가 작아 mechanical적인 제거력이 낮아 BTA가 첨가되어도 연마율에는 큰 영향이 없었다.

• Korean Journal of Materials Research
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• v.10 no.5
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• pp.369-374
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• 2000

In order to investigate the effects of addition of 1M sulfuric acid to the etching solution or 1M hydrochloric acid on the etching behavior of aluminum foil for electrolytic capacitors, the changes in the density of etch pit, the length and diameter of etch tunnels and the capacitance were analyzed using SEM, TEM, LCR meter etc. Sulfate ion as a corrosion inhibitor was contributed to the increase of the surface area comparing with chloride ion. By adding sul-furic acid the density of etch pit and the length of etched tunnel increased and the diameter of the tunnel decreased, resulting in the increase of capacitance. It was also shown that the capacitance decreased when the current density was below $0.9A/\textrm{cm}^2$, while remarkably increased in the other case.

• Corrosion Science and Technology
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• v.15 no.6
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• pp.303-310
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• 2016

The tap water used in Seoul was found to be corrosive. Its corrosivity was effectively reduced by that the additions of alkali agent such as NaOH, $Ca(OH)_2$ and corrosion inhibitor such as $H_3PO_4$. For the corrosion test, carbon steel pipe 50 m long was exposed to the drinking water produced by a pilot plant at $36.5^{\circ}C$, similar to the existing process where it takes about 20 minutes to reduce the initial chlorine content of 0.5 mg/L to 0.05 mg/L. $CO_2$ and $Ca(OH)_2$ was added not only to control the Langelier index (LI) above -1.0 and but also, to increase the duration time of residual chlorine by about 6 times. The persistence effect of residual chlorine was in the order of $H_3PO_4$ > $Ca(OH)_2$ > NaOH. Measurements of weight loss showed that corrosion inhibition was effective in order of $Ca(OH)_2$ > $H_3PO_4$ > NaOH > no addition, where the concentrations of $Ca(OH)_2$ and phosphate were 5 ~ 10 mg/L (as $Ca^{2+}$) and 1 mg/L (as $PO{_4}^{3-}$), respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.3
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• pp.195-202
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• 2006

Deterioration of sewer concrete is representative that biochemical corrosion according to the $H_2S$ has growth by inhabit sulfur-oxidzing bacteria because of special environment in sewer. But in case of domestic, fundamentally, sulfur-oxidzing bacteria could moderate development of repair material method is need because of corrosion prevent method is inconsideration with carry out to improve project. In this paper, after development of spread type antibiotic with antibio-metal, antibacterial performance about sulfur-oxidzing bacteria of antibiotic and tested to estimate fundamental properties of bonding strength, abrasion contents, contents of water absorption, contents of air permeability, carbonation depth, chloride ion penetration depth and chemical resistance of spread with antibiotic restorative mortar.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.112-113
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• 2021

Phosphate based inhibitor is playing a decisive role in inhibiting the corrosion of steel rebar in chloride condition. We have used different amount of ammonium phosphate monobasic (APMB) as corrosion inhibitor in mortar with different amount of chloride ions. The compressive strength, flexural strength, open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization resistance (PPR), scanning electron microscopy (SEM) and Raman spectroscopy were performed to access the effect of inhibitor on corrosion resistance. As the amount of inhibitor is increased, the compressive strength increased. The electrochemical results show that as the amount of inhibitor and chloride ions are increased, the total impedance and corrosion resistance of steel rebar increased attributed to the formation of the stable oxide films onto the steel rebar surface. It is suggested that APMB can work in high concentration of chloride ions present in concrete where phosphate ion helps in formation of stable and protective phosphate based oxide film.

• Conservation Science in Museum
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• v.11
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• pp.9-16
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• 2010

The National Chuncheon Museum has carried out a conservation process in order to prevent corrosion of the seated iron Śākyamuni Buddha statue from Goreyo Dysnasty for its exhibition. Before the conservation process, the surface of the artifact showed exfoliation and the artifact was damaged from rear to legs so exhibition was impossible. Therefore a process to get rid of pollution and to reinforce and protect the artifact was carried out. Before the reinforcing process, a basic test was carried out using micro crystalline wax type with reference to foreign and domestic experiment results. As a result, as wax(in xylene) 5wt% of Dongnam petrochemical Ltd. showed no efflorescence and little change in surface color and was convenient to use, it was chosen as a reinforcing agent and used to suppress corrosion. For the restoration of damaged parts, an internal support was made and used with an epoxy resin, allowing removable restoration, thus increasing effectiveness for exhibition.

• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.43-48
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• 2018

An etchant capable of forming a circuit in an FTO film that can replace ITO, which depends on full imports, was prepared. The etching solution is composed of 1 to 30% by weight of fluoride, 1 to 20% by weight of acid, 0.5 to 5% by weight of surfactant, 5 to 20% by weight of solvent, 0.5 to 10% by weight of corrosion inhibitor and the balance of water. This etchant can be etched using a dry film, thereby reducing the cost, and is free from bubbles and residue of the etchant. The characteristics of the etchant were etched in a time of 2 minute with a 100 nm thick FTO, and the etchant temperature was maintained at $50^{\circ}C$. An undercut of -0.00364% was obtained when put into a 2 minute etching solution. No harmful substances such as Cd, Pb, Hg and Cr components were measured. The use of FTO in Korea where rare earths do not exist can achieve localization and import substitution effect.