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A few nitrones such as N‐benzilidene aniline‐N‐oxide, N‐(O‐hydroxy benzilidene) aniline‐N‐oxide (HN) and N‐(α‐naphthylidene) aniline‐N‐oxide (NN) have been synthesised and investigated for evaluating their efficiency as inhibitors for the corrosion of mild steel in 1M HCl at different concentrations of nitrones ranging from 0.025‐1.0mM and at different temperatures ranging from 30‐70°C. Among these compounds NN gives the best performance even at higher temperatures. Potentiodynamic polarisation studies reveal the fact that all compounds behave as mixed type inhibitors. Hydrogen permeation studies reveal the fact that all the compounds bring down the permeation current. The absorption of these compounds on the mild steel surface from 1M HCl obeys Temkin’s absorption isotherm.

The purpose of this study is to introduce mechanochemically prepared polyaniline anticorrosive additives. In primer coating technology, there is an increasing interest in the development of efficient anticorrosive additives which replace the conventional inorganic anticorrosive pigments like heavy metal chromates and phosphates normally added to primer paints for the coating on metals. Conducting polymers are found to be better alternatives.

Polyaniline phosphate is synthesized through solid-state conditions without using any solvent. The synthesized polyaniline phosphate is added in the primer formulation instead of zinc phosphate. Primers with different quantity of zinc phosphate are also formulated and studied for comparison. The comparison between their abilities to control corrosion of carbon steel were done with application of open-circuit potential monitoring, polarization and electrochemical impedance spectroscopy methods in 3.5 per cent NaCl solution.

Corrosion studies indicate that polyaniline phosphate can improve corrosion protection properties by taking part the passivation processes. The performance of polyaniline phosphate is better than zinc phosphate.

I certify that the results are from our original research and this paper is neither considered for publication elsewhere nor published previously.

Poly(styrenesulphonic acid)‐doped polyaniline has been synthesised and the influence of this polymeric compound on the inhibition of corrosion of mild steel in 1M HCl has been investigated using weight loss measurements, galvanostatic polarisation studies, electropermeation studies and a.c. impedance measurements. The polymer acts predominantly as an anodic inhibitor. Hydrogen permeation studies and a.c. impedance measurements clearly indicate a very effective performance of the compound as a corrosion inhibitor. The adsorption of the compound on the mild steel surface obeys Temkin's adsorption isotherm.

To evaluate the inhibition efficiency (IE) of polyvinyl alcohol (PVA) in controlling the corrosion of carbon steel immersed in neutral aqueous solutions containing 60 ppm of Cl⁻, in the absence and presence of Zn²⁺. To investigate the influence of sodium sulphite (Na₂SO₃), sodium dodecyl sulphate (SDS), pH and duration of immersion on the IE of PVA‐Zn²⁺ system. To analyse the protective film formed on the metal surface.

The IE has been evaluated by weight loss method. The protective film was analysed by FTIR and fluorescence spectra.

A formulation consisting of 100 ppm of PVA and 75 ppm of Zn²⁺ offered 81 per cent IE to carbon steel immersed in a solution containing 60 ppm of Cl⁻. A synergistic effect on inhibition of a combination of PVA and Zn²⁺ was observed during the tests. The protective film consisted of the Fe²⁺‐PVA complex and Zn(OH)₂. It was found to be UV‐fluorescent. When SDS was added to the PVA‐Zn²⁺ system, the mixture showed maximum IE at the critical micelle concentration (200 ppm) of SDS (an anionic surfactant). The oxygen‐scavenging effect of Na₂SO₃ increased as the concentration of Na₂SO₃ was increased. At lower concentrations of Na₂SO₃, the transport of the inhibitors played a more major role than did the removal of dissolved oxygen. As the pH value was increased, the IE of the PVA‐Zn²⁺ system decreased. As the duration of immersion was increased, the IE was observed to decrease.

Electrochemical studies such as polarization and AC impedance spectra will enlighten more on the mechanistic aspects of corrosion inhibition.

If this study is carried out at high temperature under simulated conditions, the findings may find applications in cooling water systems.

The role of transport of inhibitors towards the metal surface from the bulk of the solution, formation of micelles by surfactants, removal of dissolved oxygen by oxygen scavenger, competition between formation of insoluble iron‐inhibitor complex on metal surface and formation of soluble iron chloride in influencing the inhibitive property has been investigated. The protective film was analysed by FTIR spectra and fluorescence spectra.

The formulation consisting of 50ppm polyacrylamide (PAA), 300ppm phenyl phosphonic acid (PPA) and 50ppm Zn²⁺ has 95 per cent inhibition efficiency in controlling corrosion of mild steel in a neutral aqueous environment, containing 60ppm Cl^—, a situation commonly encountered in cooling water systems. A discussion of mechanistic aspects of corrosion inhibition is based on the results obtained from a potentiostatic polarization study, UV‐visible, FTIR and luminescence spectra. The protective film is found to be luminescent and to consist of Fe²⁺‐PAA complex, Fe²⁺‐PPA complex and Zn(OH)₂.

To demonstrate corrosion inhibition capabilities of new cyclic nitrones, containing hydrophobic substituents.

A number of new cyclic nitrones were synthesized. Corrosion inhibition efficiencies of these organic inhibitors were determined by gravimetric and electrochemical methods, using carbon steel as the substrate metal and 1 M HCl at 60°C as the corrosive environment. Concentration of inhibitor was varied between 50 and 400 ppm.

All compounds exhibited excellent corrosion efficiencies that ranged between 90.0 and 98.3 percent in 1 M HCl at 60°C. Tafel tests corroborated these results.

The inhibitors were tested in acidic medium. It is unknown how these inhibitors will function in the presence of other ions that are typically present in natural corrosive environment.

All organic compounds presented in this work are new and this is the first time their corrosion inhibition characteristics have been evaluated.

This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity.

Different nano- and bio-materials allowed for the development of a variety of biosensors – colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors – are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples.

This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples.

This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel mercury ions detection sensors and encourage them for further research/development.