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The aim of this paper was to investigate the corrosion inhibition potential of two synthesized benzothiazines, namely, 3,4-dihydro-2-methoxycarbonylmethyl-3-oxo-2H-1,4-benzothiazine (1) and ethyl 3-oxo-3,4-dihydro-2H-1,4-benzothiazine-2-carboxylate (2) on mild steel corrosion in 1M H₂SO₄.

Corrosion inhibition efficiency (IE%) was studied by weight loss measurements, potentiodyanmic polarization method, alternating current (AC) impedance spectroscopy, fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy. Quantum chemical approach was used to complement the experimental results.

The results obtained show that the IE% increased with inhibitor concentration and follow the order 2 > 1, obeying Langmuir adsorption isotherm. The calculated quantum chemical indices were consistent with experimental results.

This paper provides information on the inhibitive properties of new set of benzothiazines on mild steel corrosion in 1M H₂SO₄.

The purpose of this paper is to use Dextrofosfomysin levophenethylamine salt to prepare HEHSPN-(Na)₂ (HSPN), a new corrosion inhibitor containing sulfur.

The inhibition efficiency for Q235 steel in hydrochloric acid has been evaluated by weight-loss test, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Surface studies were performed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM).

The results show that inhibition efficiency of HSPN increases with an increase in concentration. Adsorption conforms to Flory–Huggins uniform temperature equation, which is multi-molecular layer adsorption and belongs to physical adsorption.

This paper is intended to be added to the family of papers that deal with green corrosion inhibitors which are highly efficient and can be used in the area of corrosion prevention and control.

The purpose of this paper is to investigate the inhibitive performance of Coreopsis tinctoria (C. tinctoria) plant extract for the corrosion of mild steel in 0.5 M H₂SO₄.

The inhibition efficiency was studied by weight loss, electrochemical measurements and the surface analysis was done by Raman, scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM-EDS) and atomic absorption spectroscopy (AAS) analysis.

Maximum inhibition efficiency of C. tinctoria in 0.5 M H₂SO₄ on mild steel is 80.62 per cent (500 ppm) at 303 ± 1K. The adsorption of the C. tinctoria on the mild steel surface in 0.5 M H₂SO₄ was found to obey Langmuir adsorption isotherm. Temperature studies were carried out and the significant parameters, such as change in enthalpy (ΔH^°), change in entropy (ΔS^°) and change in free energy (ΔG°_ads) and heat of adsorption (Qads), were calculated. The productive layer formed on the mild steel surface in 0.5 M H₂SO₄ were confirmed by the Raman spectral analysis.

This paper provides information on the inhibitive properties of C. tinctoria plant extract which is found to be a good corrosion inhibitor for mild steel in 0.5 M H₂SO₄.

This paper aims to study inhibitory effect of 4-aminothiophenol on the corrosion of mild steel (MS) in 0.5 M HCl.

In this study, electrochemical experiments, quantum chemical calculations, potentiodynamic measurements, linear polarization resistance and scanning electron microscopy were used.

The experimental results suggest that this compound is efficient corrosion inhibitor and the inhibition efficiencies increase with increasing their (from 0.5 to 10.0 mM.) concentrations. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. The adsorption of these inhibitors was found to obey Langmuir adsorption model. The computed quantum chemical features show good correlation with empirical inhibition efficiencies.

The 4-aminothiophenol is suitable inhibitor for application in closed-circuit systems against corrosion. The study is original and has great impact in industrial area. The obtained theoretical results have been adapted with the experimental data.

This paper aims to study the corrosion inhibition of Methyl 2-(benzamido)-2-(4-phenyl-1H-1,2,3-triazol-1-yl) acetate (MBPTA) and Methyl 2-(benzamido)-2-(4-p-tolyl-1H-1,2,3-triazol-1-yl) acetate (MBTTA) in 1 M H2SO4 solution at 25 °C.

The authors have used weight loss measurements, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, FT-IR, quantum chemical calculations and scanning electron microscopy (SEM) techniques.

The polarization measurements indicate that both compounds are mixed type inhibitors, and that MBTTA is more effective than MBPTA. The effect of temperature on the corrosion behavior using optimal concentration of MBTTA and MBPTA was studied in the temperature range 298-328 K. SEM was used to examine the morphology of the metal surface. Thermodynamic parameters were calculated and discussed. Monte Carlo simulations were applied to lookup for the most stalls configuration and adsorption energy for the interaction of inhibitors on Fe (1 1 1) interface. The difference in inhibition efficiencies between the two organic inhibitors can be clearly explained in terms of frontier molecular orbital theory.

The authors report on the comparative inhibiting effect of two new 1,4-disubstituted 1,2,3-triazoles, namely Methyl 2-(benzamido)-2-(4-phenyl-1H-1,2,3-triazol-1-yl) acetate (MBPTA) and Methyl 2-(benzamido)-2-(4-p-tolyl-1H-1, 2, 3-triazol-1-yl) acetate (MBTTA) on mild steel corrosion in 1 M H₂SO₄ solution.

The purpose of this paper is to investigate the adsorption and corrosion inhibition of two isomeric compounds (C4H5N3) as aminopyrazine (AP) and 2-amino-pyrimidine (2AP) on mild steel (MS) in 0.5 M HCl. The study was a trial to combine experimental and modelling studies and research effect of molecular geometry on inhibition effect of inhibitor molecules.

The thermodynamic, kinetic and quantum parameters were determined. The electrochemical impedance spectroscopy and anodic polarisation measurements were obtained. The scanning electron microscope was used for monitoring electrode surface. The highest occupied molecular orbital, energy of the lowest unoccupied molecular orbital, Mulliken and natural bonding orbital charges on the backbone atoms, absolute electronegativity, absolute hardness were calculated by density functional theory (DFT)/B3LYP/6-311G (++ d,p).

Results showed that AP and 2AP suppressed the corrosion rate of MS. The corrosion current values were 0.530, 0.050 and 0.016 mA cm-2 in HCl, AP and 2AP containing HCl solutions, respectively. It was illustrated with the blocked fraction of the MS surface by adsorption of inhibitors which obeyed the Langmuir isotherm. The inhibition efficiency follows the order: 2AP > AP which is in agreement with experimental and quantum results.

This paper provides lay a bridge on the molecular geometry and inhibition efficiency by electrochemical tests and modelling study. The inhibition effect of AP and 2AP has not been compared with each other, neither experimentally nor theoretically. This study put forward possible application of 2AP as corrosion inhibitor especially for closed-circuit systems.

The purpose of this paper is to investigate the surface properties, particle sizes and corrosion inhibition performance of sodium dodecyl sulfate (SDS) in the presence of imidazolium-based ionic liquid as an additive. Up to now, different properties of alone surfactants and ionic liquids have been studied. However, few studies have been devoted to mixed ionic liquid and surfactant. The significance and novelty of this research is the investigation of 1-methylimidazolium trinitrophenoxide ([MIm][TNP]) as ionic liquid effects on SDS corrosion behavior.

The inhibition effect of [MIm][TNP], SDS and their mixtures on mild steel surface in 2 M hydrochloric acid (HCl) solution was examined by electrochemical impedance spectroscopy, potentiodynamic polarization (PDP), scanning electron microscopy (SEM), atomic force microscopy and quantum chemical calculations as well as dynamic light scattering (DLS) and surface tension measurements to discuss surface properties of studied solutions.

Based on the results, ionic liquid/SDS mixtures significantly indicated better inhibition properties than pure surfactant solution. PDP curves indicated that the studied compounds act as mixed-type of inhibitors. The critical micelle concentration, surface properties and particle sizes were investigated from the surface tension measurements and DLS results.

Adsorption of the inhibitors on the steel surface obeyed the Villamil adsorption model. SEM was used for surface analysis and verified the inhibition efficiency of mixed IL/SDS system. Quantum chemical calculations were performed using density functional theory, and a good relationship between experimental and theoretical data has been obtained.

The study aims to find new anticorrosive components from a plant source, namely, Pachysandra terminalis Sieb. et Zucc. (P. terminalis), a traditional medicinal shrub predominantly used by Tujia people.

Because phenolic components from plants are known for its numerous values in several fields, the corrosion inhibitive ability of P. terminalis extract was analyzed by electrochemical studies (polarization, electrochemical impedance spectroscopy) and surface examination (by scanning electron microscopy [SEM], energy-dispersive X-ray spectroscopy [EDX] and atomic force microscopy [AFM]).

The examination of total phenolic content (TPC), total flavonoids content (TFC) and individual phenols (UHPLC) showed the presence of 85.21 mg/g (TPC), 25.38 mg/g (TFC), protocatechuic acid (62.10 µg/g), gentisic acid (60.21µg/g), rutin (50.12 µg/g), kaempferol (46.58 µg/g) and p-Coumaric acid (42.35µg/g) . The polarization study shows that the maximum shift is (16 mV), imposing a mixed mode of inhibition, dominantly anodic. The surface morphology studies by SEM, EDX and AFM confirmed the adsorption of phytochemical components on the low carbon steel surface blocking the active sites.

The study unveils the inhibitive nature of P. terminalis, preventing aggressive attack by 0.5 M HCl on low carbon steel. This also exhibits few phenols present in methanolic leaf extract which may be the role player of corrosion inhibition.