الفهرس 
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Abstract
The thesis consists of three main chapters besides Arabic and English summaries. Chapter one is a general introduction to solution chemistry, electrochemistry, cyclic Voltammetry, types of electron transfer processes, reversible Process, a quasi- reversible process, irreversible process, cyclic voltammetry instrumentation, applications of cyclic voltammetry, types of electrodes that consists of working electrode, counter electrode and reference electrode, electrode processes, mechanisms of mass transport that could be diffusion, migration or convection, the importance of used metals, literature survey of cyclic voltammetry and literature survey of Schiff bases. Chapter two is the experimental part, includes Chemicals, Schiff Base ligands (α-H2T) and (H2B) synthesis, Preparation and analysis of metal complexes, Instruments and equipment (Elemental analyses, IR, 1H-NMR, 13C NMR, UV-vis, XRD, MS spectra and TG/DTA), Geometry optimization, Electrochemistry, Biological Activity that includes Antibacterial and antifungal assay, Antioxidant ABTS assay, Erythrocyte hemolysis, DNA- binding compounds and Cytotoxicity assay. Chapter three is the result and discussion. It divides into four different parts Part one includes cyclic voltammetry studies which consist of three divisions Division one is the study of redox behavior of cobalt chloride hexahydrate in the absence and presence of (α-H2T)& (H2B) ligands by applying cyclic voltammetry in 0.1M sodium acetate (50% DMSO) by volume as a supporting electrolyte at 298.15K. The impact of several concentrations (0.662, 1.320, 1.960& 2.600) x10-3 M had been studied. The glassy carbon electrode was used as a working electrode, platinum wire as an auxiliary electrode and silver/silver as a reference electrode. The potential range performed was from (-2.0 to 1.0) V. The formed voltammograms showed one cathodic peak at -1.3V and one anodic peak at 0.6 V. The two waves were studied and compared in the presence and absence of (α-H2T) & (H2B) ligands at the same temperature.The effect of cobalt ions concentration was studied as it was found that the increase of cobalt chloride concentration was followed by the increase of redox peaks current and the solvation parameters like (Гc, Qc, Гa & Qa) which demonstrated that the presence of a large number of electroactive species. The effect of different scan rates (0.02, 0.03, 0.04, 0.05& 0.10)V/S was also studied and it was found that the increase of scan rate was followed by the increase of both cathodic and anodic peaks but the kinetic parameters like (Гc, Qc, Гa & Qa ) decreased. The linear relationship between the square root of the scan rate and the current demonstrated that the reaction was controlled by diffusion processes. The influence of different concentrations for (α-H2T), (H2B) ligands on the electrochemical behavior of CoCl2.6H2O was determined. It was observed that the increase of ligands concentration led to a decrease in redox peaks currents. The general trend of heterogeneous rate constant (ks) is to decrease by increasing hydrazine ligands concentration. The behavior of decreasing the velocity of charge transfer indicated the binding between cobalt ions and (α-H2T), (H2B) ligands. The ratio between the ligands to the cobalt concentration was also studied. It was found that the increase of (L/M) was followed by the increase of the stability constantβ)) MX and the Gibbs free energy (∆G) which confirmed the more interaction between cobalt and ceftriaxone. The influence of previous scan rates was also determined in presence of the ligands. It was observed that the increase of scan rate was followed by the increase of redox peak Currents (ipc, ipa) but the solvation parameters such as (Qa, Qc, Γa, Γc) decreased and the reaction was controlled by diffusion mechanism. Division two includes the study of the electrochemical behavior of 1ml mole copper chloride di-hydrate had been determined in 0.1M sodium acetate at 298.15K and scan rate 0.01V.S-1.The potential range was applied from - 0.6 to 0.6 V. The resulted voltammograms indicated one peak of reduction at ” ” " ~ " ” ” - 0.10, V and one peak of oxidation at ” ” " ~ " ” ” 0.11V.The effect of different scan rates on the solvation parameters was also studied. It was found that the increase of scan rate was also followed by the increase of the potential difference (ΔE) and also the redox peaks currents but E˚ value is nearly constant. The impacts of hydrazine (α-H2T) & (H2B) ligands various concentrations (0.974, 1.940, 3.820& 5.660) x10-4 M on kinetic and solvation parameters of copper ions were determined. It was observed, the increase of the ligands concentrations was followed by the decrease of redox peaks currents and the solvation parameters decreased. The heterogeneous rate constant (ks) increased but it had smallest values in case of (H2B) which indicated the lowering of charge transfer velocity and more overlapping. The scan rate effect was also determined for copper ions in presence of the ligands. The previous behavior of scan rates was also observed.The values of stability constant (Log βj) and Gibbs free energy (∆G) were evaluated. It was noticed that their values increased by increasing the j (L/M) ratio, indicating the tendency towards the formation of the complexes with each of (α-H2T), (H2B) Ligands. The scan rates effect on the Gibbs free energy was studied for the copper complexes. It was observed that the Gibbs free energy had a largest value at scan rate 0.20 V.S-1 for (Cu-(α-H2T)) complex but its highest value was at scan rate 0.01V.S-1 for (Cu-H2B) system. Division three is about cyclic voltammetry of (Cu2+. Co2+ and Cd2+) system at potential range (- 1.5 to 1.5) V with (0.02 V.S-1) scan rate at (301.15 K) temperature. At the beginning of work, The CV voltammograms of Cu+2 offered two cathodic peaks at ” ” " ~ " ” ” (0.15, - 0.60) and two anodic peaks at ” ” " ~ " ” ” (0.3, - 0.1) V . The CV of Co2+ showed one cathodic peak at ” ” " ~ " ” ” (- 1.3) V and one anodic peak at (0.7)V and also Cd2+ indicated one cathodic reduction peak at ” ” " ~ " ” ” (- 1.0) V and one anodic oxidation peak at ” ” " ~ " ” ” (- 0.80) V. It was noticed that the increase of metal ions concentrations was followed by the increase of current for both cathodic and anodic peaks which demonstrated that the presence of a large number of electroactive species. The effect of different scan rates was also studied for 9.80x10-4 M of metal ions. It was found that the potential difference (ΔE) increased but E˚ value had approximately constant value by increasing the scan rate. As well as, the currents of anodic and cathodic peaks increased. In addition to, the diffusion demeanor was proved by the linear relationship between SQRT of scan rates and the currents of peaks. The effect of varying concentrations of (α-H2T) ligand on the electrochemical behaviors of electro-active copper, cobalt, and cadmium species was evaluated in the potential range (-1.5 to 1.5) V. When the ligand is introduced to the electrochemical cell, the values of the anodic and cathodic peak currents (ipa, ipc) decrease. The value of this current drops further when ligand concentration increases indicating a collision between ligand molecules and metal ions in the solution universe, as well as other alterations in the magnitudes of other CV parameters. The previous steps were carried out to the same metals ions in presence of (H2B) ligand at the same temperature and potential range. The complexation demeanor was explained by the change in the calculated parameters. The effect of different scan for 1:1 ratio between metals ions (Cu+2, Co+2, Cd+2) and each of (α-H2T) and (H2B) ligands was investigated. It was observed that the rise of the scan rate made an increase of currents and the heterogeneous rate constant (ks), but the kinetic parameters reduced. The linear relationship between the current and square root of scan rate confirmed that the reaction was governed by diffusion processes. The stability constants (log βMX) for (M/(α-H2T)) and (M/( H2B)) systems were calculated .It is concluded that the values (Log βj) and (∆G) increased by increasing the molar ratio (j = [L]/[M]). It was found that (j = 3) had the largest stability constant and Gibbs free energy for (Cu+2 ,Co+2)) ions with (α-H2T) and also with H2B so this ratio was preferred for forming complexes of (M/(α-H2T)) and (M/( H2B)) as (M=Cu+2,Co+2).It was also observed that (j = 2) was the best ratio for producing complexes of (Cd/(α-H2T)). The scan rate behavior was determined and its effect on the stability constant of the complex (Log βj) and the Gibbs free energy was determined. Part two: characterization of (α-H2T) and (H2B) ligands and their isolated metal complexes. The elemental analysis was determined and it revealed complete compatibility between the practical and theoretical calculations and consequently, deduced the formation of (1 metal: 1 ligand) stoichiometric complexes. Also, the other physical properties were estimated.