Inhibiting effects of 2-mercapto-1-methylimidazole on copper corrosion in 0.5M sulfuric acid

AbstractThe inhibiting efficiency of 2-mercapto-1-methylimidazole (MMI) on copper corrosion in sulfuric acid was investigated at 30°C. Its effectiveness was assessed through electrochemical impedance spectroscopy, potentiodynamic polarization and gravimetric measurements. The results of study reveal that the inhibition efficiency of MMI depends on its concentration and attains approximately 81% at 10−4M. The inhibitor was adsorbed on the copper surface according the Langmuir adsorption isotherm model. The value of standard free energy of adsorption was calculated from this isotherm

Antidiabetic treatment, obesity, and cancer risk in Algerian patients with type 2 diabetes mellitus

OBJECTIVE: Several studies have shown that antidiabetic drugs and obesity can modulate the risk of developing cancer. The objective of this study was to assess the impact of the use of antidiabetic drugs and obesity on the risk of developing cancers in type 2 diabetics. MATERIALS AND METHODS: Data for 1220 patients were collected from the processing of files and a pre-established questionnaire. The anthropobiological parameters and the associated treatment type have been unspecified. RESULTS: Women (OR=17.26; 95% CI=2.88-103.45, p<0.01), overweight individuals (OR=4.81; 95% CI=1.63-14.14, p<0.01) and hypertensive diabetic subjects (OR=3.82; 95% CI=1.39-10.49, p< 0.01) are more exposed to cancers. It is interesting to note that diabetic subjects treated with insulin have a reduced risk of developing cancer (OR=0.22; 95% CI=0.07-0.67, p<0.01). Diabetic subjects treated with metformin have a four and a half times higher risk of developing cancer (OR=4.61; 95% CI=1.48-14.37, p<0.01). CONCLUSIONS: In type 2 diabetic subjects, cancer is significantly linked to overweight, to the presence of essential hypertension in individuals under hypotensive as well as in patients treated with metformin

Synthesis, structural study and electrochemical properties of copper(II) complexes derived from benzene- and p-toluenesulphonylhydrazones

The synthesis and characterization of benzene- and p-toluenesulphonylhydrazones derived from salicylaldehyde and 2-hydroxy-1-naphthaldehyde and their Cu(II) complexes are reported. The compounds were characterized on the basis of elemental analyses, electronic and IR spectra, magnetic moments, and conductance measurements. The electrochemical behavior of the Cu(II) complexes was investigated in DMSO by cyclic voltammetry (CV), rotating disc electrode (RDE) and coulometry. The oxidative polymerization of the copper complexes on a glassy carbon electrode was carried out in DMSO

Electrochemical, theoretical and XPS studies of 2-mercapto-1-methylimidazole adsorption on carbon steel in 1M HClO4.

International audienceThe inhibition of the corrosion of carbon steel in 1 M HClO4 by 2-mercapto-1-methylimidazole (MMI) has been investigated in relation to the concn. of the inhibitor as well as the temp. using wt. loss and electrochem. measurements. The effect of the temp. on the corrosion behavior with addn. of different concns. of MMI was studied in the temp. range 30-60°C. Polarization curves reveal that MMI is a mixed type inhibitor. The inhibition efficiency of MMI is temp. independent but increases with the inhibitor concn. Changes in impedance parameters (charge transfer resistance, Rt, and double-layer capacitance, Cdl) were indicative of adsorption of MMI on the metal surface, leading to the formation of a protective film. Adsorption of MMI on the carbon steel surface is found to obey the Langmuir adsorption isotherm. Some thermodn. functions of dissoln. and adsorption processes were also detd. The XPS of the carbon steel indicated that MMI is chem. adsorbed on the steel surface. Moreover, the electronic properties such as HOMO (HOMO), LUMO (LUMO) energy levels and MO densities were calculated