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The purpose of this research paper was to investigate the use of methanolic extract of Salvia hispanica (S. hispanica) as a green corrosion inhibitor for bronze in a simulated acid rain solution.

Extract of S. hispanica was used as a green corrosion inhibitor for bronze in simulated acid rain solution. Electrochemical techniques such as potentiodynamic polarization curves, electrochemical impedance spectroscopy and electrochemical noise were used. Parameters such as polarization, charge transfer and noise resistance (Rp, Rct and Rn, respectively) were calculated.

Results showed that the extract acts as a good, anodic type of inhibitor. The inhibitor efficiency increased with increasing its concentration up to 400 ppm, decreasing beyond this concentration. Efficiency also increased with an increase in the immersion time. The inhibition was due to the adsorption of components found in the S. hispanica extract following a Langmuir adsorption isotherm.

S. hispanica extract can be used as a corrosion inhibitor for bronze in acid rain solution.

This study provides new information on the inhibition features of S. hispanica under specific conditions. This eco-friendly inhibitor could find applications to protect bronze exposed to polluted urban atmospheres.

Plant development and use as green corrosion inhibitors are already recognized as one of the most environmentally friendly and effective protocols. In recent years, efforts have been made to find green corrosion inhibitors as an alternative to synthetic inhibitors for metals in acid medium. This paper aims to report the investigation of use of aqueous extracts of Tamarindus Indica as green inhibitors for corrosion of metals within different circumstances.

The use of Tamarindus Indica extracts (leaves, stem, fruit pulp and fruit husk) as corrosion inhibitors for mild steel and aluminum in different mediums (HCl, H2SO4, formic acid and citric acid) at different temperatures was investigated.

The inhibitory efficiency of Tamarindus Indica extracts increases with increasing concentration and decreases with increasing temperature. Langmuir is the adsorption isotherm, and the extract (inhibitor) is a mixed-type inhibitor (physisorption and chemisorption).

Tamarindus extracts (leaves, stem, fruit pulp and fruit husk) are effective inhibitors and can be used to protect metals from corrosion at different circumstances.

To the best of the authors’ knowledge, this is the first review that discusses the use of Tamarindus Indica extracts as corrosion inhibitors for metals.

The aim of this paper was to explore commonalities between HIV/AIDS-related conditions, obesity and other disabling impairments as health-related barriers that limit opportunity and advancement in society and the workplace. Taking a number of examples from original fieldwork and European Union (EU) and United Kingdom (UK) law, we posited that ‘disability discrimination’ under EU law remains an indefinite, imprecise and incomplete area that requires greater alignment with the social model of disability. The principle attributes of societal discrimination towards people living with HIV and obese people are that these conditions are perceived to be primarily or in some instances, solely caused by controllable factors related often to behaviours and lifestyle choices. Strong beliefs that these conditions are controllable are perceived as a justification and in some instances encouragement for the creation of stigma and discriminative behaviours that are unjust and uninformed. The structure of the paper is as follows. First, this paper postulated how and why stigma exists towards both individuals with disabilities and also obese individuals and people living with HIV; second, reviewed the legal framework on disability discrimination in both UK and EU courts that are directly relevant to the concepts of obesity and HIV-AIDS; third, presented critical thoughts as to the extent to which emerging decisions of the Court of Justice of the EU concerning obesity and HIV-AIDS accord with the social model of disability and fourth, offered an analysis of the implications of the UK and European framework and suggested possible interventions in this area.

This paper aims to study the corrosion protection of 410 stainless steel (410SS) cracked by fatigue tests. The purpose of this study is to show that using polymeric coatings, it is possible to reduce the corrosion rate in metallic structures in operation.

Poly(3-hexylthiophene) (P3HT)/poly(methyl-methacrylate) (PMMA) composite was used as a coating to protect the cracked 410SS in the corrosive environment 0.5 M NaCl at 25°C and 80°C. Physicochemical characterization was carried out by adhesion tests, thermogravimetric analysis, nuclear magnetic resonance and size exclusion chromatography. Surface morphology was studied before and after the electrochemical tests by scanning electron microscopy. Uncoated and coated cracked 410SS were characterized by DC electrochemical techniques: linear polarization resistance and potentiodynamic polarization curves.

P3HT/PMMA coating reduced corrosion rate and crack propagation of 410SS in the corrosive medium NaCl 0.5M. The P3HT/PMMA coating increased the polarization resistance by one order of magnitude and decreased the corrosion current density by one order of magnitude, relative to the values obtained with uncoated cracked 410SS. The coating helped to have a less damaged surface and less crack propagation on the cracked 410SS. The feasibility of increasing the useful life of cracked metal structures in a saline environment was demonstrated through polymeric composite coatings.

In the literature, no works were detected that report the use of organic coatings to protect cracked metals against corrosion. This is the first reported work on the corrosion protection of 410SS in a saline medium using coatings based on P3HT/PMMA.

The purpose of this study is to investigate the corrosion behaviour of X70 steel in the presence and absence of various concentrations of inhibitor N-(2-o-Tolyl azophenyl)-acetamide (NTAA) in a CO₂ environment.

The temperature was set at 80°C, and the flow velocity was 1.5 m/s. The inhibitor concentrations were 10, 20, 30, 60 and 80 ppm, and the CO₂ partial pressure was 0.8 MPa. Weight loss method, pitting depth measurement, scanning electron microscopy and electrochemical techniques were used to investigate the inhibitory effects of the inhibitor NTAA.

The results showed that a small peak emerged in the curve of the corrosion rate versus inhibitor concentration plot at 20-30 ppm. Polarisation studies revealed that the anodic Tafel slopes changed greatly in the presence of an inhibitor; NTAA behaved as an anode-type inhibitor. At concentrations of 20-30 ppm, the incomplete coverage of the metal surface by inhibitor molecules resulted in macroscopic galvanic corrosion.

Corrosion behaviour of X70 steel in the presence and absence of various concentrations of an anode-type inhibitor was assessed. Cathodic Tafel slopes are almost unchanged, while the anodic Tafel slopes change significantly with the increase in inhibitor concentration. The corrosion rates of 20 and 30 ppm are almost three times of that of 10 ppm, which is because of the macroscopic galvanic corrosion caused by the inadequate coverage of inhibitor on steel surface.

This paper aims to report on corrosivity of secondary-stage paper mill effluent and corrosion performance of stainless steels.

For this purpose, immersion test and electrochemical polarization tests were conducted in mill and synthetic effluent to evaluate the uniform and localized corrosion.

Corrosivity of mill effluent has been compared with synthetic and primary-stage effluent of the same mill. It is observed that anions present in them, viz. SO₄−, PO₃4−, NO₂− and NO₃−, impart inhibition, whereas Cl− and chlorophenols enhance the corrosivity of the effluent. The overall effect of various components was reduction in corrosivity of secondary mill effluent.

These observations can be useful for material selection and helpful in corrosion mitigation in paper mill effluent treatment plants.