Minified dose of urispas drug as better corrosion constraint for soft steel in sulphuric acid solution

Saini, Nisha,Kumar, Rajeev,Lgaz, Hssane,Salghi, Rachid,Chung, Ill-Min,Kumar, Sumit,Lata, Suman Elsevier 2018 Journal of molecular liquids Vol.269 No.-

<P>Corrosion protective performance of commercial mild steel (soft steel) by urispas drug was evaluated by gravimetric measurements, potentiostatic polarization and electrochemical impedance spectroscopy in 1 M H2SO4 solution. The results indicate that urispas acts as quite a good corrosion constraint for mild steel exhibiting 97.85% inhibition efficiency at 150 ppm of the drug at 303 K on polarizing it electrochemically which is a quite minified amount of urispas. Weight loss study also shows that inhibition efficiency gets optimized at 150 ppm of the drug molecule at lower temperature. Polarization curves depict that the drug acts as a mixed type inhibitor. The results of electrochemical impedance spectroscopy (EIS) indicate that the charge transfer phenomenon controlled the corrosion reaction. The morphological behavior of the uncorroded and corroded coupons was investigated by scanning electron microscopy and atomic force microscopy studies. The mechanism of adsorption from the variation of inhibition effectiveness with kinetic and activation parameter through Langmuir, Freundlich, Frumkin and Flory-Huggins isotherm, put forward a significant physiochemical mode of interaction of the drug on the metal surface. The outcomes obtained from all the experimental techniques and the information obtained via molecular dynamics (MD) and density functional theory (DFT) evaluation are in good correlation. (C) 2018 Elsevier B.V. All rights reserved.</P>

Synthesis and evaluation of some new hydrazones as corrosion inhibitors for mild steel in acidic media

Lgaz, Hassane,Chaouiki, Abdelkarim,Albayati, Mustafa R.,Salghi, Rachid,El Aoufir, Yasmina,Ali, Ismat H.,Khan, Mohammad I.,Mohamed, Shaaban K.,Chung, Ill-Min Springer-Verlag 2019 Research on chemical intermediates Vol.45 No.4

Improved corrosion resistance of mild steel in acidic solution by hydrazone derivatives: An experimental and computational study

Lgaz, Hassane,Chung, Ill-Min,Albayati, Mustafa R.,Chaouiki, Abdelkarim,Salghi, Rachid,Mohamed, Shaaban K. Elsevier 2020 Arabian journal of chemistry Vol.13 No.1

<P><B>Abstract</B></P> <P>Poor corrosion resistance of mild steel (MS) is a serious concern in many industrial applications. Application of corrosion inhibitors is a possible solution to combat steel corrosion. As yet, there is very little research reported focusing on hydrazone derivatives as corrosion inhibitors, here we present a combined experimental and theoretical study of the adsorption of three newly synthesized hydrazones (HDZs), namely, (E)-N′-(4-(dimethylamino)benzylidene)-2-((2,3-dimethylphenyl)amino)benzohydrazide (HDZ-1), (E)-2-((2,3-dimethylphenyl)amino)-N′-(4-methylbenzylidene)benzohydrazide, (HDZ-2) and (E)-N′-benzylidene-2-((2,3-dimethylphenyl)amino)benzohydrazide (HDZ-3) on the MS surface in 1 M HCl. The interaction of HDZs and the metal surface was investigated using electrochemical techniques, X-ray photoelectron spectroscopy (XPS), DFT and molecular dynamic (MD) simulations. XPS shows that inhibitor molecules form a stable layer on steel surface through chemical and physical interactions. HDZs adsorption onto the steel surface was found to follow Langmuir model. Furthermore, electrochemical measurement results demonstrated that our developed inhibitors act as of mixed-type (anodic and cathodic), with HDZ-1 showing the highest polarization resistance and lowest corrosion current density. Scanning electron microscope (SEM) was used to examine the surface morphology of the steel samples. The new hydrazones showed significantly improved steel corrosion resistance, which provides opportunities to explore the inhibitive activity of structurally similar compounds.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Structural and biochemical assessment of the molecular binding of hexylresorcinol to insect immune phenoloxidase: A quest for a new insecticidal activity

Aloui Sarra,Ghazouani Tesnime,Raboudi Faten,Talbi Wafa,Vanden Broeck Jozef,Salghi Rachid,Fattouch Sami 한국곤충학회 2022 Entomological Research Vol.52 No.4

The enzyme phenoloxidase (PO) plays an essential role in insect immune defense. Phenolic compounds sharing structural homology with PO substrates could act as substrate analogues, and may interfere with insect physiological process, thus, leading to their control. Herein, the bioinformatic molecular docking was used to predict the interaction of the crystal 3D structure of the insect Manduca sexta PO (PDB: 3HHS) with the antiseptic 4 hexylresorcinol (4-Hr). The method was firstly validated using phenylthiourea (PTU) as reference ligand. Data demonstrated the ability of the 4-Hr to bind to M. sexta PO with binding energy score ΔG=372,285 Kcal/mol indicative of a plausible affinity to active site of the enzyme, nevertheless, the affinity of PTU was stronger with a binding energy of ΔG=462.173 Kcal/mol. Furthermore, biochemical in vitro assays confirmed the behavior of 4-Hr as substrate-analog when binding to the active site of the insect PO leading to its competitive inhibition. This is the first report demonstrating the molecular bases of the usefulness of hexylresorcinol as a promising insecticide. Further investigations could emphasize synergistic effects of 4-Hr with other insecticides in integrated pest management (IPM) programs.

Understanding corrosion inhibition of mild steel in acid medium by new benzonitriles: Insights from experimental and computational studies

Chaouiki, A.,Lgaz, H.,Chung, Ill-Min,Ali, I.H.,Gaonkar, S.L.,Bhat, K.S.,Salghi, R.,Oudda, H.,Khan, M.I. Elsevier 2018 Journal of molecular liquids Vol.266 No.-

<P><B>Abstract</B></P> <P>Two benzonitrile derivatives, namely 4-(isopentylamino)-3-nitrobenzonitrile (PANB) and 3-amino-4-(isopentylamino)benzonitrile(APAB) have been synthesized and evaluated as corrosion inhibitors for mild steel (MS) in 1 M HCl solution at 303 K by gravimetric, potentiodynamic polarization (PDP) curves, and electrochemical impedance spectroscopy (EIS) methods, as well as Density Functional Theory (DFT) and molecular dynamics (MD) simulations. The results suggest that tested compounds are excellent corrosion inhibitors for mild steel with PANB showing superior performance. Polarization measurements revealed that PANB and APAB behaved as mixed type inhibitors. The polarization resistance, according to EIS studies, found to be dependent on the inhibitor's concentration. The adsorption of PANB and APAB on mild steel surface obeyed Langmuir's adsorption isotherm. On the one hand, DFT and MD simulations are being used to explain the effect of the molecular structure on the corrosion inhibition efficiency and on the other hand to simulate the adsorption of benzonitrile derivatives on mild steel surface. The protection of carbon steel in 1 M HCl was confirmed by using scanning electron microscope (SEM) and Atomic Force Microscopy (AFM). Electrochemical, DFT and MD simulations results are in good agreement.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Novel benzonitrile derivatives have been synthesized and characterized. </LI> <LI> Potentiodynamic polarization curves reveal that tested inhibitors act as mixed type. </LI> <LI> The adsorption of two compounds obeys Langmuir adsorption isotherm. </LI> <LI> Surface morphology was examined by SEM and AFM. </LI> <LI> The experimental results were correlated with DFT and MD stimulation results. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A new schiff base derivative as an effective corrosion inhibitor for mild steel in acidic media: Experimental and computer simulations studies

Messali, M.,Larouj, M.,Lgaz, H.,Rezki, N.,Al-Blewi, F.F.,Aouad, M.R.,Chaouiki, A.,Salghi, R.,Chung, Ill-Min Elsevier 2018 Journal of molecular structure Vol.1168 No.-

<P><B>Abstract</B></P> <P>The inhibition effect and adsorption behavior of 4-((2,3-dichlorobenzylidene) amino)-3-methyl-1H-1, 2, 4-triazole-5(4H)-thione, noted CBAT on mild steel (MS) in 1 M hydrochloric acid solution were studied by weight loss, potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). Density Functional Theory (DFT) calculations and Molecular dynamic (MD) simulations are applied to further explain the anti-corrosion mechanism. The potentiodynamic polarization measurement illustrates the mixed type behavior of CBAT. The inhibitor can be adsorbed onto surface by both physical and chemical means obeys Langmuir. SEM micrographs revealed the presence of an adsorbed protective film on the MS surface. DFT calculations are made to correlate the efficiency of inhibitor molecule with their intrinsic molecular parameters. Further insights into the inhibition mechanism of studied Schiff base were obtained by MD simulations. The theoretical results were in agreement with the experimental data reported.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A new schiff base derivative has been synthesized and characterized. </LI> <LI> Potentiodynamic polarization curves reveal that tested inhibitor acts as a mixed type. </LI> <LI> The adsorption of the compounds obeys Langmuir adsorption isotherm. </LI> <LI> Surface morphology was examined by SEM. </LI> <LI> DFT and MD stimulation studies have been done. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>