الفهرس 
Introduction
Forms of corrosionOnly 14 pages are availabe for public view
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Abstract
This thesis is divided into three main chapters: Introduction, experimental and results <U+2013> discussion. The first chapter: contains a literature survey on importance of corrosion, classification of corrosion, factors influencing corrosion, theories of corrosion, kinetics of corrosion, mechanism of corrosion processes, forms of corrosion,and the effect of various additives on the corrosion of Csteel in acidic media was reviewed. The second chapter: deals with the experimental part, the description of the weight loss and galvanostatic polarization measurements adopted for measuring corrosion rate, preparation of inhibitor solutions, composition of material samples, test specimens and treatment, determination of inhibition efficiency and calculation of the degree of surface coverage. The third chapter: deals with the results and discussion which contains the effect of inhibitors concentrations on the inhibition efficiency at 30oC by weight loss method. The results of this method revealed that the corrosion rate is decreased with increasing the concentration of the cinnamoylmalononitriles and the order of inhibition efficiency of these compounds is: F > E > C > B > A > D, By plotting log <U+F071> against log C, a straight line was obtained, indicating that the adsorption of inhibitors on Csteel surface obeys Freundlich adsorption isotherm.,The data reveal that the rate of acidic dissolution of Csteel increases with increasing the bulk temperature, the activation parameters for the system were calculated from Arrhenius type plot and Eyring transition state equation.,The data confirm the desorption of the inhibitor molecules from the surface of the metal at elevated temperature (physical adsorption). Thermodynamic parameters <U+F044>H* and <U+F044>S* were obtained from the dependence of the equilibrium constant on temperature. The results obtained from the galvanostatic polarization method revealed that the corrosion rate is decreased by increasing the concentration of cinnamoylmalononitriles. The additives influence both anodic and cathodic processes in HCl solution. This indicates that additives act as mixedtype inhibitors, but the cathode is more polarized when an external current is applied.