الفهرس 
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Abstract
Summary : The target of this work is to estimate different cyclic voltammetry, kinetic, and thermodynamic parameters for the interaction of ammonium metavanadate with Giemsa stain dye and different ligands by different techniques. The thesis consists of three main chapters: introduction, experimental, and results and discussion. Besides, the thesis contains conclusions, English summary, Arabic summary, references, and contents. Chapter one is the introduction and it includes: electroanalytic chemistry, electrochemical mechanisms, the electrochemical cell design, electrodes used in cyclic voltammetry, supporting electrolytes, solvents used, cyclic voltammogram, cyclic voltammogram analysis, studying reaction mechanism using cyclic voltammetry, free energy change of redox reaction, and types of crystalline solids, ionic crystals, and covalent crystals. The properties of compounds used were also given in this chapter like ammonium metavanadate (NH4VO3), pyrazole derivative, Giemsa stain, and some literature survey on similar works using cyclic voltammetry. Chapter two is the experimental part of the thesis. It includes firstly the reagents and solutions which are mainly: H3PO4, KCl, HCl, NH4VO3, and Giemsa stain. Also pyrazole derivative and CoCl2 were also mentioned to know their origin. Properties of three ligands were also given in this chapter. Explanation of the formation of cobalt complexes were also given here in this chapter. The methods used for analyzing the compounds and complexes obtained are given here. The computational studies were done using Gaussian 09 calculations of electronic and structural properties were obtained. Chapter three is the results and discussion. It is divided into eight parts : Part one: It contains the estimation of cyclic voltammetry data for the interaction of ammonium metavanadate (AMV) alone and in presence of Giemsa stain at 291oK in 0.1M H3PO4. from cyclic voltammetry diagram, we noticed one main reduction peak for AMV at ” " ~ " ” +0.3V is corresponding to the reduction of +5 vanadium to +4 one. The main oxidation peak of vanadium was observed at ” " ~ " ” -0.07V corresponding to the oxidation of V (IV) to V (V). Small reduction peak at ” " ~ " ”-0.4 V is the reduction of vanadium (IV) to vanadium (III). The reaction between NH4VO3 and H3PO4 forming VO2+ which reduced to VO+2 using two electrons and finally VO2+ is reduced to V+3. We noticed that redox reaction of AMV in 0.1M H3PO4 is quasireversible because of decreasing scan rate. The peak potential is shifted to negative values. Stability constants and Gibbs free energies for complexation of Giemsa stain with AMV were calculated and found to be greater than the use of ligand pyrazole derivative indicating greater interactions. Part two: It is the cyclic voltammetry of ammonium metavanadate (NH4VO3) with pyrazole derivative in 0.1 M H3PO4. The redox behavior of ammonium metavanadate (NH4VO3) was studied by the interaction with pyrazole derivative (3-(3,5-dimethyl-1H-pyrazol-1-yl)-3-oxopropanenitrile in 0.1M H3PO4 at scan rate 0.02V.S-1. It was observed that there is an increase in Ipa and Ipc for the waves obtained by increasing NH4VO3 concentration. Analysis was done for AMV+ pyrazole derivative on 1:1 complex to estimate the stability constants and Gibbs free energies of complexation. It was observed that the decrease in scan rate is followed by an increase in βj and ΔG for 1:1 stoichiometric complex formed by the interaction of AMV with pyrazole derivative. Part three: The redox behavior of NH4VO3 in 0.1M KCl media. This part contains the redox behavior of NH4VO3in absence and presence of Giemsa stain in 0.1M KCl at 287.5K. The cyclic voltammograms is different in 0.1M KCl than other electrolytic solutions. It was observed that one reduction irreversible wave was obtained corresponding to the reduction of V (V) to V (IV). Different additions of Giemsa stain (GS) to AMV in 0.1 M KCl increase in stability constants and Gibbs free energies of complexation indicating interaction between AMV and GS in 0.1M KCl forming complex. It was found that by decreasing scan rate the peak potential of complexes is shifted towards more negative potentials indicating a quasi-reversible reaction. Part four: It is studying the solvation, redox, kinetic, and thermodynamic parameters for AMV in absence and presence of Giemsa stain in 0.1M HCl. The effect of AMV concentration showed two redox peaks in the forward sweep and one peak in the reverse sweep. Two reduction waves were observed at 0.9 V& 0.3V versus Ag/AgCl electrode in 0.1M HCl. Each wave uses one electron for reduction due to the transfer of VO2+ VO+2 V+3. The oxidation process proceeds via the transfer of VO+2 to VO2+. Also the cyclic voltammetry, kinetics, and thermodynamic parameters were calculated and their values were discussed. The stability constants and Gibbs free energies of complexation for interaction of AMV with GS in 0.1 M HCl gave little values than that in 0.1M KCl. Part five: It is the redox behavior of ammonium metavanadate (AMV) in absence and presence of Giemsa stain GS in organic media ethanol using tetrabutyl ammonium bromide (TBAB). Different concentrations of AMV in ethanol medium using tetrabutyl ammonium bromide (TBAB) show one reduction peak at” " ~ " ”-0.5 V and one oxidation peak at +0.7 V. Part six: It is the study of redox behavior of ammonium metavanadate (NH4VO3) with Aniline blue in pH 4.The effect of NH4VO3 concentrations using buffer solution (pH= 4) and complexation effect with the interaction of AMV with Aniline blue. Two reduction waves were observed at ” " ~ " ”0.7 and ” " ~ " ”0.9V with one electron mechanism. The solvation electrical parameters were calculated and discussed. Good Gibbs free energies values were obtained. It also indicated the formation of complex from the interaction of AMV with Aniline blue at pH 4. Part seven: Published research on pyrazole derivatives with transition elements was reviewed as these compounds are important for their biological activity. The ligands that were prepared in this study are: H2DMP (3-(3,5-dimethyl-1H-pyrazol-1-yl) HCPA 2-Cyano-N-pyridin-yl-acetamide CMPPA 3-(mercapto-amino phenyl-1-pyridine-2-amino) penta-4-en-2-one. Methods for the preparation of H2DMP, HCPA, CMPPA and their complexes with Co(II) ion in the presence of ammonium metavanadate were described using methods of precision analysis, thermal analysis, infrared, ultraviolet, optical, proton nuclear resonance, magnetic measurements and scanning electron microscopy (SEM) in order to clarify the surface shape and measure the size of the molecules, and the study of X-ray diffraction (EDX) was carried out at room temperature. Micro analyses for (C, H, N, Cl, Co) of the studied ligands and their solid complexes have demonstrated compatibility with the proposed molecular formulas. The infrared spectra of the ligands and their complexes were compared and changes in the adsorption beams characteristic of the ligands were observed. * Ligand (H2DMP) behaves as a three-claw binegative through a dehydrogenated (C=O) group and(C=N) pyridine and an asymmetric carboxyl group. * Ligand (HCPA) acts as a mononegative bidentate through the dehydrogenated group (C=O) and(C=N) pyridine. * Finally, the ligand (CMPPA) acts as a zero charged bidentate through (C=O), and (C=N) pyridine. The thermal dissociation of solid compounds in the presence of nitrogen in the temperature range (25-1000) oC has been identified and the quantitative calculations calculated from the thermal analysis curves have been consistent with the proposed formulas for these compounds and the change of the energy rate required for each phase of thermal cracking. Molecular modeling calculations of the compounds studied were also done through the application of the DFT function, then the structure of the separated compounds was determined using the Gaussian program, and then an analysis of the orbits and the optimal shape of the compounds. The lengths of the bonds between the atoms were clarified and the energy gap was calculated between the highest electron-filled orbits and the lowest electron-filled orbits, hardness, smoothness, chemical voltage, and electrical negativity. The analysis of natural associative orbits also showed how the charge moves between the associative orbits and indicated the places of electronic density. Part eight: Biological activity assay. The antimicrobial activity, antioxidant activity, and DNA damage of the prepared ligands and their metal complexes were done experimentally.