• 제목/요약/키워드: Electrochemical studies

검색결과 458건 처리시간 0.025초

양쪽성 이온 및 인산염 기반 하이브리드 방청제의 전기화학적 특성에 관한 실험적 연구 (Experimental study on the electrochemical properties of zwitterion and phosphate-based hybrid inhibitors in reinforced concrete)

  • 트란 득 탄;정민구;이한승;양현민;싱 지텐드라 쿠마
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2022년도 가을 학술논문 발표대회
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    • pp.37-38
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    • 2022
  • During the past decades, the corrosion of the steel rebar embedded in concrete structure surrounding marine environment is actually problematic and required the suitable preventive method. An eco-friendly corrosion inhibitor mix is investigated to stifle the active corrosion in comparison with other commercial corrosion inhibitors. The hybrid inhibitor enhances the corrosion resistance and the workability of concrete. However, it reduces the compressive strength slightly after 28-day-age. The electrochemical studies and mechanical studies are pointed out the corrosion resistance property, corrosion kinetics, and the mechanical properties of all concrete samples. H-3 is the optimum dose of hybrid inhbitor that meets the demand of both electrochemical property and mechanical property. It performs the noble features due to the formation of optimum amount of P-Zwitterions-(Cl)-Fe complex onto the steel rebar surface.

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알칼리 축전지의 활물질에 관한 연구(II)-니켈양극의 전기화학적 거동- (Studies on the Active Materials of Alkaline Storage Battery(II) Electrochemical Behavior of. Nickel Anode)

  • 주충렬;이주성
    • 한국표면공학회지
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    • 제15권3호
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    • pp.146-151
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    • 1982
  • The electrochemical reaction behavior of nickel electrode of the nickel-cadium battery system in potassium hydroxide solution has been studied by cyclic voltammetry, controlled potential electrolysis and X-ray diffraction method. It has been found that the reaction mechanism of positive nickel electrode for charging was assumed to be proten transfer step with a rate controlling diffusion process and char-ging state of positive electrode was amorphous $\beta$-NiOOH.

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Surface Characteristics and Biocompatibility of Hydroxyapatite Deposited Ti alloys by Electrochemical Deposition

  • Lee, Kang;Choe, Han Cheol
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2015년도 추계학술대회 논문집
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    • pp.141-141
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    • 2015
  • In this study, a series of hydroxyaptite (HAp) are produced on Ti dental implant using electrochemical deposition. Based on the preliminary analysis of the coating structure, composition and morphology. In vitro studies were performed with MC3T3-E1 cell to investigate the effect of biological change on different surface conditions.

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A.C. 임피던스 측정에 의한 아연의 전착기구에 관한 고찰 (Studies on Electrodeposition Mechanism of Zinc By A.C. Impedance Measurement)

  • 안덕수;예길촌
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2007년도 추계학술대회 논문집
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    • pp.26-26
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    • 2007
  • To attest zinc electrodeposition mechanism, electric circuit models for zinc electro reaction on Pt electrode are analyzed from the a.c. impedance data. Electrochemical reactions of zinc deposition are composed of the three electrochemical reactions on the cathode layer and of the induced electrode layers.

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Spectral, Electrochemical, Fluorescence, Kinetic and Anti-microbial Studies of Acyclic Schiff-base Gadolinium(III) Complexes

  • Vijayaraj, A.;Prabu, R.;Suresh, R.;Kumari, R. Sangeetha;Kaviyarasan, V.;Narayanan, V.
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3581-3588
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    • 2012
  • A new series of acyclic mononuclear gadolinium(III) complexes have been prepared by Schiff-base condensation derived from 5-methylsalicylaldehyde, diethylenetriamine, tris(2-aminoethyl) amine, triethylenetetramine, N,N-bis(3-aminopropyl)ethylene diamine, N,N-bis(aminopropyl) piperazine, and gadolinium nitrate. All the complexes were characterized by elemental and spectral analyses. Electronic spectra of the complexes show azomethine (CH=N) within the range of 410-420 nm. The fluorescence efficiency of Gd(III) ion in the cavity was completely quenched by the higher chain length ligands. Electrochemical studies of the complexes show irreversible one electron reduction process around -2.15 to -1.60 V The reduction potential of gadolinium(III) complexes shifts towards anodic directions respectively upon increasing the chain length. The catalytic activity of the gadolinium(III) complexes on the hydrolysis of 4-nitrophenylphosphate was determined. All gadolinium(III) complexes were screened for antibacterial activity.

Corrosion Inhibition Studies on Low Carbon Steel in Hydrochloric Acid Medium Using o-Vanillin-Glutamine Schiff Base

  • Thusnavis, G. Rexin;Archana, T.V.;Palanisamy, P.
    • Corrosion Science and Technology
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    • 제21권1호
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    • pp.32-40
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    • 2022
  • The o-Vanillin - Glutamine Schiff base [2-Hydroxy-3-Methoxy BenzylidineCarbomyl) -2-Butanoic Acid] was examined for low carbon steel corrosion inhibition in acid media. Weight loss studies were carried out at three different temperatures to determine the inhibition efficiency (IE). Electrochemical impedance spectroscopy revealed that the charge transfer resistance controlled the corrosion reaction and Tafel polarization indicated that the Schiff base acts as mixed mode of inhibitor. SEM images were recorded for the surface morphology of the low carbon steel surface. DFT studies revealed corrosion control mechanisms using quantum chemical parameters such as EHOMO, ELUMO, energy gap (∆E), chemical Hardness (η), chemical Softness (σ), Electronegativity (χ), and the fraction of electron transferred (∆N), which is calculated using Gaussian software 09. The gas-phase geometry was fully optimized in the Density Functional Theory (DFT/B3LYP-6-31G (d)).The DFT results are in good agreement with the experimental results. All the results proved that the Schiff Base (2-Hydroxy-3-Metoxy BenzylidineCarbomyl) -2-Butanoic is a suitable alternative for corrosion inhibition of low carbon steel in acid media.

Electrochemical Response of Polymer Actuators using Finite Element Formulation and ANSYS/Emag

  • Kang, Sung-Soo
    • Journal of Advanced Marine Engineering and Technology
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    • 제34권3호
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    • pp.369-375
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    • 2010
  • The two-dimensional finite element formulation for the basic field equations governing electrochemical responses of ionic conducting polymer-metal composite(IPMC) actuators is proposed in the present study. Biaxial deformation of a platinum plated Nafion actuator having 4 electrodes is dominated by electro-osmosis of hydrated ions and self-diffusion of free water molecules. Some numerical studies for IPMC actuators with electric field are carried out in order to show the validity of the proposed formulation and electric field analysis for the initial condition of total charge distribution are conducted using commercial code ANSYS/Emag.

Strong Electric Field in Ultra High Vaccum

  • Shin, Sunghwan;Kim, Youngsoon;Kang, Hani;Kang, Heon
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.262-262
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    • 2013
  • In surface chemistry area, many scientists studied the electrochemical reaction by changing work-function of metal; however, these methods had the weakness that it did not create the electric field. Unlike earlier studies, our capacitor-method makes a strong electric field in ice film. This electric field was induced by soft landing $Cs^+$ ions on ice film, and the strength was measured by the vibrational Stark shift of acetonitrile. In our system, the electric field strength is $10^9$ V/m and it is almost same in the electrochemical cell. This capacitor model provides new method to investigate the electrochemical reaction in vacuum system.

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