The corrosion behavior of 2024 aluminium alloy was investigated in alkaline medium (pH=13) containing 0.6 . in absence and presence of different concentrations of three amino acids separately [Methionine, Glutamice acid and Lysine] as environmentally friendly corrosion inhibitors over the temperature range (293-308)K. Electrochemical polarization method using potentiostatic technique was employed. The inhibition efficiency increased with an increase of the inhibitor concentration but decreased with increase in temperature . The maximum efficiency value was found with lysine =80.4 of 293 k and 10 . concentration of lysine. The adsorption of the amino acids was found to obey Langmuir adsorption isotherm . Some thermodynamic parameter ∆ and activation energy ∗ were calculated to demonstrate the mechanism of corrosion inhibition . The kinetic parameters were calculated using Arrhenius theory. Suitable mechanism was proposed for the corrosion of 2024 aluminium alloy in alkaline medium. The polarization measurements indicated that the inhibitor is of mixed type. The surface morphology of uninhibitied and inhibited samples were investigated using optical microscope.
Amino Acids as Environmentally-Friendly Corrosion Inhibitors for 2024 Aluminium Alloy in Akaline Medium
corrosion inhibition
2024 alloy
Amino acids
Free energy of adsorption
Adsorption mechanism.
Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
أثـر الأدوات الداخلية لحوكمة الشركة على رأس المال الـعـامـل وانعكاسهما علـى القيـمـة الاقتصـادية المضـافـة: دراســة تطبيقيـة علـى عينــة مـــن الشـركــات الصنــاعــيــة المـدرجــة في بورصــة عـمّــان لــلأوراق المـالـيـة
/ Corporate Governance Instrument- Net Working Capital- Economic Value Added- Weighted Average Cost of Capital- Capital Asset Pricing Model
أدوات حوكمة الشركات- صافي راس المال العامل- القيمة الاقتصادية المضافة- المتوسط الموزون لكلفة راس المال- نموذج تسعير الاصول الرأسمالية.
Abstract
Objective of this research focused on testing the impact of internal corporate governance instruments in the management of working capital and the reflection of each of them on the Firm performance. For this purpose, four main hypotheses was formulated, the first, pointed out its results to a significant effect for each of corporate major shareholders ownership and Board of Directors size on the net working capital and their association with a positive relation. The second, explained a significant effect of net working capital on the economic value added, and their link inverse relationship, while the third, explored a significant effect for each of the corporate major shareholders ownershi
... Show More