EFFECT OF SULFACETAMIDE ON THE COMPOSITION OF CORROSION PRODUCTS FORMED ONTO CARBON STEEL SURFACE IN HYDROCHLORIC ACID

IUPAC name N- [(4-aminophenyl) sulfonyl] acetamide (APSA) on the corrosion of carbon steel in 1.0 M HCl solution has been investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and XPS analysis. The electrochemical measurements indicated that the presence of APSA in 1.0 M HCl solution decreases the corrosion current (i corr ) and increases the polarization rezistance (R p ). XPS surface analysis showed at this stage, in the absence of APSA, that the main product of corrosion is a non-stoichiometric Fe 3+ oxide/oxidehydroxide, consisting of a mixture of Fe 2 O 3 and FeO(OH), where FeO(OH) is the main phase. Moreover, in presence of inhibitor the surface layer consists of FeO(OH) rather than pure oxide, adsorbed molecules of sulfacetamide and inorganic compounds such as: sulfides, carbonates, sulphates, nitrates, which were obtained by electrochemical degradation of APSA. UV-Vis spectrophotometry and HPLC technique were performed to determine the medium composition before and after corrosion. The results showed a decrease of the inhibitor concentration in 1.0 M HCl solution after carbon steel corrosion, indicating an adsorption process between organic compound molecules from aqueous phase and the electrode surface and/or the electrochemical degradation of APSA

Generation of Porous Alumina Layers in a Polydimethylsiloxane/Hydrogen Peroxide Medium on Aluminum Substrate in Corona Discharges

The porous alumina (Al2O3) layer obtained at the interface between polydimethylsiloxane/hydrogen peroxide medium and aluminum substrate under charged and neutral species injection produced in negative corona discharges in air at atmospheric pressure is analyzed by different methods in this paper. The scanning electron microscopy investigations showed the uniform distribution of the pores formed in the alumina layer and their columnar structures. Both energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) measurements indicate that during the anodization process of the aluminum in the polydimethylsiloxane/hydrogen peroxide medium in corona discharge the incorporation of silicon in the structure of the alumina layer is possible

Losing silence, gaining acceptance:A qualitative exploration of the role of thoughts in adult patients with subjective tinnitus

Objective: Tinnitus is one of the most common somatic symptoms to affect humanity. Prevalence rates in adult populations range from 8.2 to 20.1%. Our aim was to understand the beliefs and interpretations of tinnitus and the experience of living with it. Design: An in depth grounded theory interview study. Grounded theory is an inductive approach to developing theory. Sample: Thirteen contrasting people with tinnitus who had sought help from clinical services in England. Results: We identified that the thinking patterns that people held around their tinnitus impacted how they experienced it. A core category emerged from the data, “sense making”. Around “sense making” eight other themes operated. Results are discussed in relation to the literature on tinnitus acceptance and beliefs. Conclusions: The aim of interventions is to foster understanding and enhance perceptions of control, which may minimise the emotional impact of tinnitus and reduce the perceived severity of consequences

Corrosion Inhibition of Carbon Steel in Hydrochloric Acid Solution Using a Sulfa Drug

The corrosion inhibition of carbon steel in 1.0 mol L–1 HCl in the presence of an antibacterial sulfa drug Sulfathiazole, IUPAC name 4-amino-N-(1,3-thiazol-2-yl) benzene sulfonamide (TBSA) was investigated using mass loss and electrochemical measurements such as: potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Surface chemistry was analyzed by X-ray photoelectron spectroscopy (XPS). For the study of the surface morphology scanning electron spectroscopy (SEM) was used. The results showed that TBSA acts as a corrosion inhibitor in 1.0 mol L–1 HCl solution by suppressing simultaneously the cathodic and anodic processes via adsorption on the carbon steel surface and that the inhibition efficiency increases with increasing concentration. XPS analysis revealed that the corrosion product consists of an oxyhydroxide/oxide mixture and that the iron oxyhydroxide proportion is higher than the iron oxide proportion