• Proceedings of the Korea Concrete Institute Conference
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• 1994.04a
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• pp.148-151
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• 1994

Up to now, sea sand without complete removal of salt is being used in the construction works because there is little satisfactory counterplan for the substitute aggregate. In the case that such sea sand is used in the reinforced concrete, the residual salt gives rise to deterioration phenmenon and iron corrosion, reducing durability of the ferro-concrete structures. The paper, an experimental study on the effect of corrosion protection by tighting concrete used SF and FA, is to investigate general steel bar's corrosion and to develop concrete using sea sand economically after it is analyzed and examinated ratio of the corrosion area affected by the autoclave cycle. As a test results, as for corrosion area ratio, it is very effective to use admixrutes such as SF and FA which decrease corrosion area remarkably with increasing the amounts of admixtures. Accordingly the use of admixtures is advantageous for tightening concrete and has an effect of salt damage prevention and rust protection in concrete used sea sand.

• Magazine of the Korea Concrete Institute
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• v.6 no.5
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• pp.123-130
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• 1994

In this paper, a development of composite bridge decks was proposed for design of civil and architectural structures to reuse the empty cans and plastics etc. The experimental specimens were made of rigid foamed urethane taking advantage of corrosionlessness in steel bridge decks, and simplicity in the field construction. 'Therefore, introducing the empty cans into the rigid foamed urethane, this experimentation have been carried out to demonstrate and evaluate the structural behavior by means of loading and vibration tests in composite bridge decks. Consequently, it was possible that had a good effect on the structural behavior by absorbing the strain due to the low elasticity of rigid foamed urethane, and not influence to cans in composite bridges.

• The monthly packaging world
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• s.262
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• pp.94-104
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• 2015

환경부는 '화학물질의 등록 및 평가 등에 관한 법률(화평법)'과 '화학물질관리법(화관법)' 시행규칙을 공포하고 지난 달부터 시행했다. 환경부에 따르면 두 법안은 화학물질의 체계적인 관리로 사전에 안전사고를 예방하고 국민건강과 환경을 보호하기 위해 제정됐다. 화학물질의 생산 유통 등 모든 과정의 안전관리를 강화하는 것이 골자다. 우선 화평법 시행에 따라 모든 신규 화학물질과 연간 1톤 이상 제조 수입되는 기존 화학물질에 대한 등록이 의무화되고 등록 신청 기준도 강화된다. 다만 제조 수입량이 연간 1톤 미만일 경우 등록 신청 제출 자료를 정식 등록 9개보다 적은 4개로 간소화하고 등록기간도 30일에서 3~7일로 줄였다. 또 유해물질 함유제품으로 인한 피해를 예방하기 위해 생활화학 제품 15종을 우려제품으로 지정해 안전 표시기준을 준수하도록 했다. 관리대상 품목은 세정제 합성세제 표백제 섬유유연제 코팅제 접착제 방향제 탈취제 방청제(금속부식 방지제) 김서림방지제 물체염탈색체 문신용염료 소독제 방충제 방부제 등이다. 화관법에서는 유해 화학물질 취급 때 공통 적용되는 46개 준수사항을 규정하고 물질별로 구체적인 취급기준을 고시하도록 했다. 취급시설의 설치 관리기준도 시설 종류별로 구체화했다. 새로 도입되는 장외 영향평가는 취급시설 설치자가 화학사고 발생 시 사업장 주변지역 사람이나 환경에 미치는 영향을 사전에 평가해 시설을 안전하게 설계 설치하도록 규정했다. 과징금과 행정처분 기준도 구체화했다. 행정처분은 2년 내 위반 횟수에 따라 경고 개선명령 영업정지 허가취소로 차등화하고 사고가 일어나면 사상자와 사업장 밖 피해액을 기준에 따라 산정해야 한다. 본 고에서는 두 법률의 주요 내용과 함께 주요 문의 사항을 살펴봄으로써 이해를 도우고자 했다.

• Journal of Environmental Health Sciences
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• v.29 no.3
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• pp.65-71
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• 2003

The injection concentration of corrosion inhibitor increases under the pH 7, temperature of 2$0^{\circ}C$, and alkalinity of 35 mg/l (as CaCO$_3$), the corrosion rate gradually decreased. When the corrosion inhibitor of 10 mg/l is injected, the corrosion rate for carbon steel pipe, galvanized steel pipe, and copper pipe reduces for 37, 66 and 61 % respectively that it is more efficient on galvanized steel pipe and copper pipe. As a result of examination of corrosion rate at pH 6, 7, and 8 when injecting 10 mg/l of corrosion inhibitor under the conditions of 2$0^{\circ}C$ in water temperature and 35 mg/l (as CaCO$_3$) in alkalinity, the efficiency of the corrosion inhibitor increases as the pH increases. For carbon steel pipe, it does not show much a difference with the change of the pH condition, but galvanized steel pipe and copper pipe clearly show the corrosion rate depending on the change of the pH condition. The efficiency of corrosion inhibitor is low as the concentration of residual chlorine is high, but it does not show a great influence at 0.4 mg/l or less. For each pipe type, in the case of carbon steel pipe, the range of increase of corrosion speed following the residual chloride is higher than the other pipe types. In the meantime, the effect following the residual chlorine in copper pipe is low.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.7-8
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• 2017

Corrosion of reinforced concrete embedded in concrete is a deterioration phenomenon due to intrusion of embodied or Airborne chloride ions. Corrosion of a embedded steel increases the volume of the rebar and causes damage to the structure such as cracking and peeling of the concrete. This causes penetration of various corrosive factors and accelerates the corrosion of reinforcing bars, which has a serious effect on the durability of the structure. Researches on the corrosion phenomenon of these rebars by electrochemical methods have been carried out for a long time, but it is a lack of research in Korea. Therefore, in this study, one of electrochemical experimental methods, Tafel extrapolation method, was used to evaluate the performance of reinforcing bars according to the amount of NaCl and LiNO₂ added to concrete.

• Applied Chemistry for Engineering
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• v.17 no.5
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• pp.498-503
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• 2006

i-(2',5'-Diketotetrahydrofuranyl)octadecenyl acid (OSA), an intermediate for the lubricating oil additive, was prepared by the ene-reaction of oleic acid with maleic anhydride. The reaction progress was monitored by gas chromatography by analyzing the amount of OSA. The series of succinimidyl compounds were synthesized by the reaction of alkyl amines and OSA. As a kind of lubricant additives, demulsibility, anti-wear, and anti-corrosion properties of these succinimidyl compounds were measured. The derivative of octadecylamine which has relatively long-chained alkyl group has showed good properties.

• Special Issue of the Society of Naval Architects of Korea
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• 2007.09a
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• pp.48-56
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• 2007

Wash primer was applied to cargo tank of Membrane-LNG Carrier (M-LNGC) for corrosion resistance and high bond-strength with the mastic. However, a lack of bond-strength verification at high thickness wash primer coating resulted in strict coating thickness control. Therefore wash primer was controlled below DFT(Dry Film Thickness) $30{\mu}m$. In order to develop the wash primer satisfying GTT (GAZ TRANSPORTAION TECHNIGAZ) standard even at high thickness, we evaluated coating properties such as wash primer/mastic bond-strength, corrosion resistance, as well as workability for the newly formulated wash primer materials. The newly formulated wash primer had high bonding-strength to mastic even at high thickness and had proper corrosion resistance and workability suitable to yard condition.

• Corrosion Science and Technology
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• v.17 no.1
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• pp.30-36
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• 2018

The high rate of corrosion of magnesium alloys makes it limited for industrial applications. Therefore, surface treatment is required to enhance their corrosion resistance. In our study, a chemical conversion coating for protecting the corrosion of the magnesium alloy, AZ31B, was prepared by using a phosphate-permanganate solution. The chemical conversion coating had a limited protection ability due to defects arising from cracks and pores in the coating layer. The sol-gel coating was prepared by using trimethoxymethylsilane (MTMS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) as precursors, and aluminum acetyl acetonate as a ring opening agent. The corrosion protection properties of sol-gel and conversion coatings in 0.35wt% NaCl solution were measured by the electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization test. The EIS results indicated that the resistance of the chemical conversion coating with the sol-gel coating was significantly improved through the sol-gel sealed phosphate-permanganate conversion coating. The results of the potentiodynamic polarization test revealed that the sol-gel coating decreased the corrosion current density ($I_{corr}$). The SEM image showed that the sol-gel coating sealed conversion coating and improved corrosion protection.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.134-135
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• 2013

In this study, the physical properties and antifouling were investigated to make the Marine growth antifouling coatings by blending of synthesized silicone resin and pigment with a low surface tension. To examine the film properties and foul release of the prepared coatings, film specimens were prepared with the prepared coatings and anti corrosion coatings. The test results showed that the silicone type antifouling coatings had very excellent antifouling properties rather than any other coatings because of the coating films had followed the low surface tension and elasticity, and prevention of adhesion for marine growth and mechanical adhesions.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.2
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• pp.215-223
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• 2006

The internal corrosion of water distribution systems is the main cause for the problem of the public health threat as well as water leakage in the damaged pipeline, red water, and odor and taste of the tap water. This study was examined the effect of chemicals used for pH and alkalinity control and corrosion inhibitors for producing the optimal corrosion control method. Corrosion study at different pH and alkalinity indicated that these control using alkaline chemicals was effective in corrosion rate, Fe release reduction, but examined to be increased in turbidity and corrosion-by-products(TTHMs) problems. The turbidity was slightly increased, requiring caution in controlling corrosion with $Ca(OH)_2$. At pH 9.0, TTHMs concentration is increased two times corn pared with non-control of pH. Using the pipe which had experienced 28 years of exposure, iron release was decreased with the corrosion inhibitor. Consequently, pH, Alkalinity control method using alkaline chemicals must be complemented by corrosion inhibitor application for efficient corrosion control.