الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
1- The introduction includes a literature survey of the different theories
of corrosion and corrosion inhibition. The corrosion of cadmium in
aqueous solutions (alkaline, acidic and neutral) is given with particular
emphasis on the effect of aggressive as well as inhibitive anions.
2- The anodic and cathodic polarization curves are constructed for
cadmium in sodium carbonate solutions. This is made to elucidate the
effect of sodium carbonate concentrations on the kinetic parameters of
the dissolution of cadmium studied. Increase of sodium carbonate
concentration is accompanied by increase in the corrosion current
density.
3- Additions of different concentrations of surfactants are studied in O. I
M sodium carbonate solution. This showthat:
a- As the concentration of surfactants increases the corrosion
current density decreases and inhibition efficiency is increased.
b- The increase in inhibition efficiency is in the following order:
surfactant I < surfactant II < surfactant III < surfactant IV < surfactant V.
4- Effect of temperature on the dissolution of cadmium in 0.1 M sodium
carbonate is studied, as the temperature is raised it is found that:
a- The corrosion potential is shifted to more negative value.
b- The corrosion current density is increased.
5-· The effect of temperature on the dissolution of cadmium in 0.1 M
SOdilUDcarbonate in the presence of 1000 ppm of cationic surfactants
(1-V) respectively, is studied and reveals that:
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a- As the temperature is raised the corrosion potential is shifted
to more negative values.
b- The corrosion current density is increased.
c- The inhibition efficiency decreases.
6- Some thermodynamic parameters such as free energy of activation,
enthalpy of activation and entropy of activation are calculated using
the transition state equation,
7- The anodic and cathodic polarization curves are constructed for
cadmium in hydrochloric acid solutions. This is made to elucidate the
effect of hydrochloric acid concentrations on the kinetic parameters of
the dissolution of cadmium studied. Increase of hydrochloric acid
concentration is accompanied by increase in the corrosion current
density.
8- Additions of different concentrations of surfactants are studied in 0.1
M hydrochloric acid solution. This shows that:
a- As the concentration of surfactants increases the corrosion
current density decreases and inhibition efficiency is
increased,
b- The increase in inhibition efficiency is in the following order:
surfactant I ...s:urfactant II < surfactant III< surfactant IV < surfactant V.
9- Cyclic voltammograms are constructed for cadmium in a solution
different concentrations of sodium carbonate solution which lead to:
c- Two anodic peak (A) and (C) and passive region (B) are
observed before oxygen evolution takes place.
d- At high concentration of Na2C03 another anodic peak
appears.
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e- As the concentration of Na2C03 solution increases the
corrosion current density of peak (A) and peak (C) increases.
9- Cyclic voltammograms are constructed for cadmium in 0.1 M
Na2COJ at different scanning rates show that:
a- An increase in scan rate is accompanied by an increase in the
current density.
b- As the sweep rate increases, the anodic peak is observed to
shift towards less negative potentials.
10- Cyclic voltammograms are constructed for cadmium in 0.1 M
Na2COJ in absence and presence of increasing concentrations of
NaCl. Increasing of the concentration of NaCl leads to:
a- Increases the dissolution current density (ipeak).
b- The change in the integrated charge amount (~qa)increases
slightly in presence of low concentrations of chloride ions,
while at higher concentrations of chloride ions ~qa changes
markedly and linearly.
12- Potentiodynamic anodic polarization curves of cadmium are reported
in 0.1M Na2COJ containing increasing concentrations of cr ions. It
is found that:
a- The cr ions cause the destruction of the passivating oxide
film and initiating of pitting corrosion.
b- The pitting corrosion potential varies with the logarithm of
molarity of cr ions to give sigmoidal nature (S-shaped
curve ).
13- Trials are made to inhibit pitting corrosion using cationic surfactants
of oleyl amido derivatives. These anions shiftes the pitting
potential to more positive values. indicating the inhibition effect of
these surfactants.