الفهرس 
Chapter One IntroductionOnly 14 pages are availabe for public view
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Abstract
Artemisia Judaica herb extract (AJH) was tested as an eco-friendly corrosion protection of carbon steel (CS) in 1.0 M hydrochloric acid as attacking medium utilizing non electrochemical methods (mass reduction (MR)), and electrochemical methods such as (EIS) AC electrochemical impedance spectroscopy, and (PP) Tafel polarization tests. The obtained data revealed that the protective efficiency increased with increasing extract dose and also increased with increasing temperature. Surface examination was performed by (AFM) atomic force microscope (in order to determine the degree of roughness of the CS surface), (SEM) scanning electron microscope (in order to determine the film formed on CS surface) and (FT-IR) Fourier transforms infrared spectroscopy (in order to determine the adsorbed groups on CS surface). These tests revealed that the extract molecules form a film on CS surface. The AJH extract was adsorbed physically and spontaneously on CS surface and follows Langmuir’s isotherm. The adsorption (Kads, ΔH0ads , ΔG0ads) factors were calculated using adsorption isotherm, and activation (E*a, ΔH*, ΔS*) parameters were determined from Arrhenius and transition state theories and debated. Polarization data revealed that this extract is mixed type one, i.e. affects both anodic metal dissolution and cathodic hydrogen evolution. EIS data revealed that the charge transfer resistance (Rct) increased, on the other hand the capacitance double layer (Cdl) decreased in the presence of AJH extract. Toxicity of the extract was determined by Microtox Model 500 analyzer. Different components in the extract were dedicated by HPLC apparatus. Quantum chemical calculations were performed using Materials Studio 7.0 software and discussed for five main components in the extract.