• 한국해양공학회지
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• 제25권2호
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• pp.85-91
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• 2011

Many protection methods such as surface coating, electric protection, or other methods have been applied to the numerous steel structures widely used in continental and marine areas to control their corrosion, which is done from an economic point of view. Most of these steel structures are primarily protected by coating methods. However, some steel piles under seawater are protected by the electric protection method, that is, either using an impressed current or a sacrificial anode method. Furthermore, environmental contamination may cause a severely corrosive environment, which, in turn, causes the accelerated corrosion of steel structures. Subsequently, coated steel structures could deteriorate more rapidly than the designed lifetime because of the acid rain caused by air pollution, etc. Therefore, a coating of marine paint exposed to seawater, that is, underwater hardening painting, is increasingly required to be fast drying as well as highly corrosion resistant. In this study, five types of underwater hardening paints were prepared with different resin series and additives. Their corrosion and water resistances were investigated using electrochemical methods such as corrosion potential, polarization curves, impedance and cyclic voltammogram measurements, etc. Even though it is generally accepted that the corrosion resistance of bare steel tends to increase with a shift of the corrosion potential in the noble direction, the corrosion resistance of a sample with a coating exhibited a relatively better tendency when it had a lower corrosion potential in this study. The corrosion current density was also decreased with a decrease in the diffusion limiting current density, which may mean that there is some relationship between corrosion and water resistance. The S sample of the ceramic resin series showed the relatively best corrosion and water resistance among those of samples, while the worst corrosion and water resistance were observed for the R sample of the epoxy resin series. The corrosion and water resistance of those samples tended to deteriorate with an increase in the immersion days, and their corrosion and water resistances were considered to be apparently improved by the types of resin and additives.

• 공업화학
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• 제5권4호
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• pp.698-705
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• 1994

Linseed oil fatty acid(LOFA), phthalic anhydride(PAA) 및 maleic anhydride(MA), trimethylol propane(TMP)을 사용하여 기본적인 유장(oil length) 50%의 중유성 기본 알키드를 합성하고 trimethylol propane triacrylate(TMPTA)를 그라프트 공중합시켜 MA/TMPTA 변성 알키드 수지를 제조하였다. 수지의 산가는 MA 첨가량으로 제어하였으며, 수용화에는 N,N-dimethylethanol amine(DMEA)를 사용하였다. TMPTA의 첨가량 변화에 의한 분자량, 유리 전이온도, 수용화 후의 점성도 및 그라프트율을 측정하였으며, 가교도막의 경화온도별 겔분율 변화를 조사하였다. 또한 멜라민 수지 경화 도막의 내열성, 내자외선성, 내수성 및 저장 안정성을 측정하고, TMA/TMPTA 변성 알키드 수지의 물성과 비교하였다. TMPTA의 첨가량이 증가할수록 수용화 후의 점성도, 겔분율, 그라프트율 및 분자량이 증가하였으며, 유리 전이온도(Tg)는 감소하였다. 고형분 함량에 따른 점성도 변화는 고형분 30%일 때보다 40%일 때가 더 낮게 나타났으며, 중화도에 따른 점성도 변화는 중화도가 높을수록 낮은 점성도를 나타내썼다. 내열성, 내자외선성, 내수성은 MA/TMPTA 변성 알키드 수지가 TMA/TMPTA 변성 알키드 수지보다 우수하였으나, 저장 안정성은 TMA/TMPTA 변성 알키드 수지가 우수함을 알 수 있었다.

• 한국해양공학회지
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• 제27권2호
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• pp.114-120
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• 2013

A superhydrophobic surface means that the contact angle between the solid surface and a water droplet is more than $150^{\circ}$. Materials with a superhydrophobic surface have a self-cleaning function because of the Lotus effect, in which water is not absorbed by the material but rolls off of it. If such a Lotus effect can be applied to the surface of underwater vessels, submarines, torpedos, and so on, enhanced vessels can be made based on this lubricant effect reducing the friction coefficient for the liquid. Because polymer composites can be easily applied in various nanotechniques, they are more advantageous than conventional materials like iron in terms of a superhydrophobic surface. Furthermore, a superhydrophobic surface bring enhanced anticorrosion and ecotechnology because no paint is needed on underwater vessels.

• 한국지반환경공학회 논문집
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• 제19권3호
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• pp.15-24
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• 2018

전자기파는 주변 매질의 전기전도도와 유전율에 민감한 영향을 받기 때문에 지반의 특성을 평가하는데 널리 이용되고 있다. 본 연구에서는 염수환경에서도 다양한 농도의 중금속을 검측하기 위하여 시간영역반사법을 이용한 전자기파 측정 프로브를 제작하였다. 중금속으로는 구리를 사용하였으며, 실내 실험을 통해 구리 농도에 따라 적용 가능한 프로브를 선정하였다. 실내 실험에서는 염도 3%의 염수에 용해된 구리의 농도가 0, 0.01, 0.05, 0.1, 0.5, 1, 5, 그리고 10mg/L가 되도록 8단계로 용액을 조성하였다. 프로브는 염수에서도 전자기파를 측정할 수 있도록 5가지의 각기 다른 절연재로 코팅하여 비교하였다. 코팅재로는 에폭시, 탑코트, 바니쉬, 아크릴페인트, 히팅튜브를 사용하였으며 코팅재에 따른 전자기파의 신호 특성을 분석하였다. 실험 결과, 아크릴페인트와 히팅튜브로 코팅된 프로브는 구리 농도에 따른 신호 변화가 관측되지 않았으며, 에폭시, 탑코트, 바니쉬의 경우 구리 농도가 증가함에 따라 반사된 전자기파의 전압의 크기가 감소하는 것으로 나타났다. 에폭시로 1회 코팅한 프로브와 탑코트로 코팅한 프로브는 구리의 농도가 5mg/L 이하일 때 민감한 반응을 보였으나 에폭시로 2회 코팅한 경우, 구리의 농도가 5mg/L보다 클 때 더 민감하게 반응하였다. 본 연구의 결과는 절연재로 코팅된 시간영역반사법을 이용한 전자기파 측정 프로브가 염수에 녹아있는 중금속의 농도를 평가하는데 활용될 수 있음을 보여준다.

• Advances in nano research
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• 제15권5호
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• pp.441-449
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• 2023

Heavy metals, widely present in the environment, have become significant pollutants due to their excessive use in industries and technology. Their non-degradable nature poses a persistent environmental problem, leading to potential acute or chronic poisoning from prolonged exposure. Recent research has focused on separating heavy metals, particularly from industrial and mining sources. Industries such as metal plating, mining operations, tanning, wood and chipboard production, industrial paint and textile manufacturing, as well as oil refining, are major contributors of heavy metals in water sources. Therefore, removing heavy metals from water is crucial, especially for safe water supply in swimming and water sports. Iron oxide nanoparticles have proven to be highly effective adsorbents for water contaminants, and efforts have been made to enhance their efficiency and absorption capabilities through surface modifications. Nanoparticles synthesized using plant extracts can effectively bind with heavy metal ions by modifying the nanoparticle surface with plant components, thereby increasing the efficiency of heavy metal removal. This study focuses on removing lead from industrial wastewater using environmentally friendly, cost-effective iron nanoparticles synthesized with Genovese basil extract. The synthesis of nanoparticles is confirmed through analysis using Transmission Electron Microscope (TEM) and X-ray diffraction, validating their spherical shape and nanometer-scale dimensions. The method used in this study has a low detection limit of 0.031 ppm for measuring lead concentration, making it suitable for ensuring water safety in swimming and water sports.

• 수산해양교육연구
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• 제12권2호
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• pp.164-175
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• 2000

Port facilities and marine structures used in marine environment were encountered to corrosion damages because of the influence of Cl-. Generally, to protect these accidents, anti-corrosion paint and epoxy coating have been used. But they were still remained erosion-corrosion damage like impingement erosion, cavitation erosion and deposit attack. It is necessary to develope the new composite lining material in order to protective those corrosion damages. In this paper, polyester glass flake, vinylester glass flake lining and epoxy coating for SS400 were investigated by the electrochemical polarization test and the impingement-cavitation erosion test for corrosion behaviour under the sea water. The main results obtained are as follows ; 1) Epoxy coating appear potentiodynamic polarization behaviour, but polyester glass flake and vinylester glass flake lining do not appear potentiodynamic polarization behaviour. 2) Open circuit potential of polyester glass flake lining is more noble than that of epoxy coating and corrosion current density of polyester glass flake lining is less drained than that of epoxy coating in sea water. 3) Open circuit potential of vinylester glass flake lining is more noble than that of polyester glass flake lining and corrosion current density of vinylester glass flake lining is less drained than that of polyester glass flake lining in the sea water.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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• pp.359-365
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• 2000

Port facilities and marine structures used in marine environment were encountered to corrosion damages because of the influence of $Cl^-$. Generally, to protect these accidents, mainly applied anti-corrosion paint and epoxy coating. But it was still remained erosion-corrosion damage such as impingement erosion, cavitation erosion, deposit attack. There was needs to develope the new coating materials to protective those corrosion damages. This paper, polyester glass flake, vinylester glass flake lining and epoxy coating for SS were investigated electrochemical tests and cavitation erosion test for corrosion behaviour under sea water. The main results obtained are as follows, 1) Surface of epoxy coating appear erosion pin hole but surface of polyester glass flake and vinylester glass flake lining do not appear erosion pin hole after impingement-cavitation erosion test in sea water. 2) Weight loss of polyester glass flake and vinylester glass flake lining do not occur after impingement-cavitation erosion test in sea water. 3) Corrosion current density of polyester glass flake lining less drained than epoxy coating and substrate under corrosion potential.. 4) Corrosion current density of vinylester glass flake lining with three coating less drained than that of polyester glass flake lining with two coating.

• Corrosion Science and Technology
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• 제6권5호
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• pp.219-226
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• 2007

Pre-construction primer (PCP), or shopprimer, have been applied to steel plates to control temporary corrosion during ship fabrication. For surface preparation at ship block stage, in common shipyard practices, welding beads, burnt and rusted areas shall be blasted or power tool cleaned and the contamination such as zinc salt shall be removed with blasting or power tool. Whereas, the sound film of PCP needs not to be removed or roughened as the paint having good compatibility with PCP is used for the first coat. In many cases, however, full blasting or sweep blasting on the sound PCP treated block assemblies was requested. There still has been argument about the legitimacy of this practice, thus, it is critical to evaluate the quality of the coating system applied on the sound PCP retained condition, comparing with the one applied on the full blasted or sweep blasted condition. In this study, two different epoxy systems for water ballast tank were applied on the surfaces with sound PCP condition, full blasted condition, and sweep blasted condition. Coating performances such as durability, anti-corrosion, cathodic disbondment resistance were evaluated. The test results clearly indicated that the sound film of PCP needed not to be removed or roughened as the paint having good compatibility with PCP based on inorganic zinc silicate.

• 한국건축시공학회지
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• 제21권6호
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• pp.573-581
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• 2021

본 연구에서는 메카노크로믹 센서의 건설 구조물 건전도 모니터링 활용 가능성을 검토하기 위한 기초 단계의 실험적 연구를 진행하였다. 콘크리트 재료의 마감 유형에 따른 메카노크로믹 센서의 변형 및 변색 특성을 파악하였다. 그결과, 콘크리트 시험체의 인장변형률이 증가할수록 메카노크로믹 센서의 변형 및 변색 반응도가 증가하는 것을 확인하였다. 또한, 콘크리트, 우레탄, 에폭시, 수성페인트 및 유성페인트의 마감 환경의 차이는 메카노크로믹 센서의 변형 및 변색 특성에 영향을 미치지 않았다.

• 한국구조물진단유지관리공학회 논문집
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• 제17권2호
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• pp.110-116
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• 2013

최근 건설 기술의 발달과 건설 환경 변화로 인하여 콘크리트 구조물이 대형화, 고층화되고 있으며 그에 따른 구조물 유지관리와 성능향상을 위한 보수 보강 및 주변환경과의 조화 등 외관을 중시하는 경향이 늘어가고 있다. 본 연구는 토목, 건축분야에서 사용되고 있는 콘크리트 구조물에 적용 가능한 친환경 내구성 도장에 관한 것으로, 기존 유 무기질계 도장재의 온도변화에 따른 신축성, 외벽과의 접착성, 균열과 박리로 인한 내구성 문제를 보완하고 외적 미관 향상에 목적이 있다. 그 방법으로 전처리 혼합물에 고농축 방수액과 접착증강재를 균일하게 혼합한 친환경 전처리 페인트를 조성하여 콘크리트 중성화방지, 내마모성, 은폐력, 접착력, 온도저항성, 내화학성등의 내구성 시험을 하였다. 그 결과, 친환경 전처리 페인트의 도장에 따른 은폐율은 시험기준인 0.96 이상으로 나타났으며, 내마모성시험에서도 일반 수성페인트값 75mg 보다 우수한 1mg의 값을 얻었으며, 인장강도는 방수시방서 기준보다 6.5배 크게 나타났다.