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    The inhibiting effect of N - cyclohexyl - N?- phcnyl thiourea (CPTU) and N-naphthyl-N?- phenyl thiourea (NPTU) on the corrosion of mild steel in aqueous solution of 0.1 N H2SO4 have been demonstrated using potentiodynamic polarization technique. The polarization data have shown that these compounds act as efficient anodic inhibitors for mild steel. Adsorption of these compounds on the mild steel surface was found to obey Temkin's adsorption isotherm. Good inhibition efficiency (IE) was evidenced in both the compounds and it was found to vary with concentration of the inhibitors. The kinetic parameters of adsorption obtained reveal spontaneous adsorption and a strong interaction of the compounds on the mild steel surface. © 2006 SAEST.
    (Inhibition of mild steel corrosion in sulphuric acid solution) Divakara Shetty, S.; Shetty, P.; Sudhaker Nayak, H.V.
    2006
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    Corrosion inhibition of mild steel in acid media by quinolinyl thiopropano hydrazone
    (2009) Saliyan, R.V.; Vasudeva Adhikari, A.V.
    3-([8-(trifluoromethyl)quinolin-4-yl]thio)-A''-(2)3,4- trihydroxybenzylidene)propano hydrazide (TQTHBH) was synthesized, characterized and tested as a corrosion inhibitor for mild steel in HC1 and H2SO4 solutions using weight loss method, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization methods. The corrosion inhibition efficiency results obtained by all the above three techniques were in good agreement with each other. Scanning electron microscopy (SEM) technique is used to confirm the effectiveness of inhibition of mild steel corrosion in acid media. The results showed that TQTHBH is a good inhibitor for mild steel in acid media. The inhibition efficiency of TQTHBH in different media was in the following order: 2 M HC1 < 1 M H2SO4 < 1 M HC1 < 0.5 M H2S04. The inhibition was assumed to occur via adsorption of the inhibitor molecule on the metal surface. The adsorption follows Langmuir isotherm. TQTHBH acts as an anodic inhibitor. The protection efficiency increased with increasing inhibitor concentration in the range 0.222 x 10"4 - 11.086 x 10^ M, also slightly increased with increasing temperature. Chemisorption mechanism is proposed. The apparent activation energies and enthalpies for the adsorption process were determined. The fundamental thermodynamic functions were used to gain information about TQTHBH inhibitory behaviour.
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    3-Methyl-4-amino-5-mercapto-1,2,4-triazole as corrosion inhibitor for 6061 Al alloy in 0.5 M sodium hydroxide solution
    (Springer New York LLC barbara.b.bertram@gsk.com, 2011) Kumari, P.D.R.; Nayak, J.; Nityananda Shetty, A.N.
    3-Methyl-4-amino-5-mercapto-1,2,4-triazole (MAMT) was synthesized, and its inhibition action on the corrosion of 6061 Al alloy in 0.5 M sodium hydroxide was investigated by means of potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The effect of inhibitor concentration, temperature, and concentration of the corrosion medium on the inhibitor action was investigated. The surface morphology of the metal surface was investigated by scanning electron microscopy (SEM). The inhibition efficiency increased with the increase in the concentration of the inhibitor, but decreased with the increase in temperature. Both thermodynamic and kinetic parameters were calculated and discussed. The adsorption of MAMT on the base alloy was found to be through physisorption, obeying Langmuir's adsorption isotherm. The results obtained from both the techniques were in good agreement with each other. © 2011 ACA and OCCA.
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    Corrosion inhibition of 6061 Al-15 vol. pct. SiC(p) composite and its base alloy in a mixture of sulphuric acid and hydrochloric acid by 4-(N,N-dimethyl amino) benzaldehyde thiosemicarbazone
    (2011) Geetha, G.M.; Nayak, J.; Nityananda Shetty, A.N.
    The corrosion inhibition characteristics of 4-(N,N-dimethylamino) benzaldehyde thiosemicarbazone (DMABT) on the corrosion behavior of 6061 Al-15 vol. pct. SiC(p) composite and its base alloy were studied at different temperatures in acid mixture medium containing varying concentrations of hydrochloric acid and sulphuric acid using Tafel extrapolation technique and ac impedance spectroscopy (EIS). The effect of inhibitor concentration, temperature and concentration of the acid mixture media on the inhibitor action was investigated. It was found that inhibition efficiencies increase with the increase in inhibitor concentration, but decrease with the increase in temperature and with the increase in concentration of the acid media. Thermodynamic parameters for dissolution process were determined. The adsorption of DMABT on both the composite and base alloy was found to be through physisorption obeying Freundlich adsorption isotherm. © 2010 Elsevier B.V. All rights reserved.
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    3,4-Dimethoxybenzaldehydethiosemicarbazone as corrosion inhibitor for aged 18 Ni 250 grade maraging steel in 0.5 M sulfuric acid
    (2011) Poornima, T.; Nayak, J.; Nityananda Shetty, A.N.
    The corrosion inhibition of the aged 18 Ni 250 grade maraging steel in 0.5 M sulfuric acid by 3,4-dimethoxybenzaldehydethiosemicarbazone(DMBTSC) has been investigated by potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) techniques. The inhibition efficiency increased with the increase in inhibitor concentration and decreased with the increase in temperature. Polarization curves indicated mixed type inhibition behavior affecting both cathodic and anodic corrosion currents. The thermodynamic parameters of corrosion and adsorption processes were evaluated. The adsorption of DMBTSC on the aged maraging steel surface was found to obey the Langmuir adsorption isotherm model, and the calculated Gibb's free energy values confirm the spontaneous adsorption. The results obtained by the two techniques were in good agreement. © 2010 Springer Science+Business Media B.V.
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    Effect of 4-(N,N-diethylamino)benzaldehyde thiosemicarbazone on the corrosion of aged 18 Ni 250 grade maraging steel in phosphoric acid solution
    (2011) Poornima, T.; Nayak, J.; Nityananda Shetty, A.N.
    4-(N,N-diethylamino)benzaldehyde thiosemicarbazone (DEABT) was studied for its corrosion inhibition property on the corrosion of aged 18 Ni 250 grade maraging steel in 0.67M phosphoric acid at 30-50°C by potentiodynamic polarization, EIS and weight loss techniques. Inhibition efficiency of DEABT was found to increase with the increase in DEABT concentration and decrease with the increase in temperature. The activation energy Ea and other thermodynamic parameters (?Gads0, ?Hads0, ?Sads0) have been evaluated and discussed. The adsorption of DEABT on aged maraging steel surface obeys the Langmuir adsorption isotherm model and the inhibitor showed mixed type inhibition behavior. © 2011 Elsevier Ltd.
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    Corrosion inhibition of 6061 aluminium alloy/SiCp composite in hydrochloric acid medium using 3-chloro-1-benzothiophene-2-carbohydrazide
    (2011) Kini U, U.; Shetty, P.; Divakara Shetty, S.; Arun Isloor, M.
    The inhibitive action of 3-chloro-1-benzothiophene-2-carbohydrazide (CBTC) on the corrosion behavior of 6061 Al alloy/SiCp composite has been studied at four different temperatures (30°, 40°, 50° and 60°C) in hydrochloric acid medium (0.5 and 1 M) using Tafel extrapolation technique and weight loss method. Polarization curves indicate that CBTC acts as cathodic inhibitor. Inhibition efficiency is found to increase with increasing inhibitor concentration upto a critical value and with decreasing temperature. The inhibition efficiencies obtained by Tafel extrapolation technique and weight loss method are in good agreement. The adsorption of the inhibitor on the composite surface is found to obey Temkins' and Langmuir adsorption isotherms. The inhibition is governed by physisorption mechanism.
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    3-Methyl-4-amino-5-mercapto-1,2,4-triazole as corrosion inhibitor for 6061/Al-15 (vol-%) sic(p) composite in 0.5M sodium hydroxide solution
    (2011) Kumari, P.D.R.; Nayak, J.; Nityananda Shetty, A.N.
    3-Methyl-4-amino-5-mercapto-1,2,4-triazole (MAMT) was investigated for its inhibition action on the corrosion of 6061/Al - 15 (vol-%) SiC(p) composite in 0.5M sodium hydroxide solution at different temperatures by potentiodynamic polarization and electrochemical impedance spectroscopic techniques. The effect of inhibitor concentration, temperature and concentration of the corrosion medium on the inhibitor action was investigated. The inhibition efficiency increased with the increase in the concentration of inhibitor but decreased with the increase in temperature. Both thermodynamic and activation parameters were calculated and discussed. The adsorption of MAMT on the composite was found to be through physisorption obeying Langmuir's adsorption isotherm.
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    The corrosion inhibition of maraging steel under weld aged condition by 1(2E)-1-(4-Aminophenyl)-3-(2-Thienyl)prop-2-en-1-one in 1.5 M hydrochloric acid medium
    (Springer New York LLC barbara.b.bertram@gsk.com, 2012) Sanatkumar, B.S.; Nayak, J.; Nityananda Shetty, A.N.
    The influence of 1(2E)-1-(4-Aminophenyl)- 3-(2-Thienyl)prop-2-en-1-one (ATPI) on the corrosion behavior of weld aged maraging steel in 1.5 M hydrochloric acid was studied by potentiodynamic polarization method and AC impedance (EIS) technique at different temperatures. The results showed that the inhibition efficiency of ATPI increased with the increase in the concentration of inhibitor and decreased with the increase in temperature. ATPI acts as a mixed type inhibitor without affecting the mechanism of the hydrogen evolution reaction or iron dissolution. The adsorption of ATPI on a weld aged maraging steel surface obeys the Langmuir adsorption isotherm equation. Both activation and thermodynamic parameters were calculated and discussed. ATPI inhibits the corrosion through both physisorption and chemisorption on the alloy surface. The surface morphology of the weld aged maraging steel specimens in the presence and the absence of the inhibitors was studied by the respective SEM images. © ACA and OCCA 2011.
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    Influence of 2-(4-chlorophenyl)-2-oxoethyl benzoate on the hydrogen evolution and corrosion inhibition of 18 Ni 250 grade weld aged maraging steel in 1.0 M sulfuric acid medium
    (2012) Sanatkumar, B.S.; Nayak, J.; Nityananda Shetty, A.N.
    Electrochemical corrosion behavior and hydrogen evolution reaction of weld aged maraging steel have been investigated, in 1.0 M sulfuric acid solution containing different concentrations of 2-(4-chlorophenyl)-2-oxoethyl benzoate (CPOB). The data obtained from polarization technique showed that the corrosion current density (i corr) and the hydrogen evolution rate decrease, indicating a decrease in the corrosion rate of weld aged maraging steel as well as an increase in the inhibition efficiency (?%) with the increase in inhibitor concentration. Changes in impedance parameters were indicative of adsorption of CPOB on the metal surface, leading to the formation of protective film. Both activation (E a) and thermodynamic parameters (?G ads 0, ?H ads 0 and ?S ads 0) were calculated and discussed. The adsorption of CPOB on the weld aged maraging steel surface obeyed the Langmuir adsorption isotherm model. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) study confirmed the formation of an adsorbed protective film on the metal surface. © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.