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To evaluate the inhibition efficiency of 1‐methyl 2‐mercapto imidazole (MMI) in controlling the corrosion of carbon steel in sulphuric acid and to study its action mechanism.

The effect of concentration, immersion time and temperature on the behaviour of this inhibitor has been studied using weight loss, d.c. polarisation and a.c. polarisation techniques.

The results show that MMI is a mixed type inhibitor. Changes in impedance parameters (charge transfer resistance, R_t; and double layer capacitance, C_dl) were indicative of adsorption of MMI on the metal surface, leading to the formation of a protective film that grew with the increasing exposure time. Adsorption of MMI on the carbon steel is found to obey the Langmuir adsorption isotherm. The inhibition efficiency of MMI is temperature‐independent and its addition leads to a small increase in activation corrosion energy.

Surface analytical techniques such as X‐ray photoelectron spectroscopy and Auger spectroscopy can enlighten more on the mechanism of corrosion inhibition.

A survey of literature has shown that no work using electrochemical techniques has yet been done on MMI as corrosion inhibitor for carbon steel in sulfuric acid.

To assess the protective effect and adsorption behaviour of Azadirachta indica extract in controlling mild steel corrosion in 1 M H₂SO₄ and 2 M HCl.

The inhibitive effect of the plant extract was monitored using the gas‐volumetric technique. The inhibition mechanism was inferred by curve fitting of the experimental data to known adsorption isotherms and the trend of inhibition efficiency with temperature.

Azadirachta indica extract effectively inhibited steel corrosion in the acid media studied by virtue of adsorption. The inhibitor adsorption characteristics were approximated by Langmuir isotherm. The extract functioned as a mixed inhibitor, depending on its concentration. The prime effect at lower concentration was mitigation of the cathodic reaction by physical adsorption of protonated species in the extract and at higher concentration the anodic reaction was inhibited by chemisorption of molecular species.

This paper provides novel information on the effectiveness of Azadirachta indica extract as a green corrosion inhibitor for steel in highly acidic environments as well as possible mechanisms of the inhibitive action.

Surface pretreatment of iron and its alloys to remove stains and inorganic contaminants on the metal surface undergoes dissolution by virtue of the strong acidic media thereby increasing its susceptibility to corrosion. The purpose of this study is to explore the corrosion mitigation prospects of green corrosion inhibitors on mild steel surface.

Corrosion inhibition performance of Garcinia gummi-gutta leaf extract (GGLE) was explored against mild steel in 1 M HCl solution using the weight-loss method, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) techniques. Surface characterization was carried out to study the mechanism of inhibitor action.

The concentration of GGLE varied from 100 to 6,000 ppm and the result indicates that corrosion inhibition efficiency was amplified by raising the inhibitor concentration. The maximum inhibition efficiency was 82.2% at 6,000 ppm concentration. EIS results show the development of a protective layer of inhibitor molecule over the metal surface and PDP demonstrates that the inhibitor operates as a mixed-type inhibitor. Scanning electron microscopy and atomic force microscopy were executed to assess the surface morphology and roughness, respectively.

To the best of the authors’ knowledge, so far, no studies have been reported on the corrosion inhibition performance of GGLE which is rich in many bioactive components especially hydroxyl citric acid. This work encompasses the corrosion inhibition capability of GGLE against mild steel in an acidic medium.

This study aims to examine whether Globularia alypum (Ga) lyophilized aqueous leaves extract treatment improves cardiometabolic syndromes such as hyperglycemia, lipid profiles and oxidative damage resulting from a high-fructose diet induced in hypertriglyceridemic rats.

A total of 24 male Wistar rats weighing 80 ± 5 g were first randomly divided into 2 groups. A total of 12 control rats (C) were fed a standard-diet (St-D) and 12 high fructose (HF) rats were fed a high-fructose diet (HF-D) containing St-D in which cornstarch was substituted by fructose (61.4%). After 15 weeks of feeding, body weight (BW) was about 320 ± 20 g and hypertriglyceridemia was noted in HF vs C group (2.69 ± 0.49 mmol/L) vs (1.25 ± 0.33 mmol/L). Each group of rats was then divided into two equal groups (n = 6) and fed during four weeks either a St-D or HF-D, treated or not with 1% of Ga extract (C-Ga) and (HF-Ga). After 28 days, fasting rats were anesthetized and blood and tissues were removed to measure biochemical parameters.

The results showed no significant differences in BW and insulinemia between all groups. Ga extract supplementation reduced glycemia (−36%), glycosylated hemoglobin (−37%), Homeostasis Model of Assessment-Insulin Resistance index (−34%) and triacylglycerol’s contents in plasma (−33%), very low density lipoproteins–low density lipoproteins (VLDL-LDL) (−48%), liver (−52%) and aorta (−39%); total cholesterol concentrations in aorta was 3.7-fold lower in HF-Ga vs HF group. Ga treatment reduced lipid peroxidation in plasma, VLDL-LDL, red blood cells (RBC), liver, muscle and kidney by improving superoxide dismutase (SOD) activity and glutathione peroxidase (GPx) in RBC and catalase (CAT) activity in kidney (p < 0.05). Moreover, Ga ameliorates glutathione (GSH) production in RBC (+41%) and kidney tissues (+35%).

Ga extract ameliorated cardiometabolic syndrome by its hypotriglyceridemic effect and prevented development of insulin resistance. It reduces lipid peroxidation by enhancing non-enzymatic (GSH) and enzymatic (SOD, GPx and CAT) antioxidant defense systems in high-fructose hypertriglyceridemic rats. Therefore, supplementation of Ga leaves extract as an adjuvant could be used for the treatment of hypertriglyceridemia and the prevention and/or the management of cardio-metabolic adverse effects.

The purpose of this paper is to synthesize Cr-ZSM-5 using hydrothermal synthesis in acidic fluoride medium and the investigation of its catalytic performance in heterogeneous oxidation of 2-mercaptobenzothiazole in the presence of H₂O₂.

The framework was characterized by chemical composition, FT-IR, UV-visible spectroscopy, N₂ adsorption (BET), and diffraction x-ray (DRX). FT-IR spectroscopy shows the characteristic band of Si-O-Cr linkage around 960-990 cm⁻¹ and bands around 688-690 and 627 cm⁻¹, indicating the presence of extraframework chromium oxide. UV spectra show a shoulder around 244-257 and bands around 360-380 nm, assigning the tetrahedral coordinated environment in (O²⁻=Cr⁶⁺) − (Cr⁵⁺-O⁻¹), charge transfer transition state (CT) of isolated Cr (VI) inside the structure of Cr-ZSM-5.

The catalytic degradation of 2-mercaptobenzothiazole by H₂O₂ heterogenous oxidation using catalyst Cr-ZSM-5 showed the formation of bis (benzothiazoyl) disulfide with 95 percent yield.

The application of this process in the environment (catalysis, adsorption, and degradation of organic compounds).