الفهرس 
Chapter one (1. Introduction)Only 14 pages are availabe for public view
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Abstract
The present thesis comprises three main chapters in addition to
Arabic and English summaries as well as the relevant references.
The First Chapter: - Introduction
This chapter includes a scientific literature survey related to
nitrogen containing ligands and their metal complexes, regarding design,
synthesis, characterization and different biological applications as
anticancer, antibacterial and antifungal. Also, the previous studies carried
out on the effect of gamma irradiation on some different compounds
especially metal complexes.
The Second Chapter: - Experimental
This chapter includes a detailed account about the method of
synthesis of the current nitrogen containing ligand and its metal
complexes by reacting the ligand under study with different metal salts
as: manganese(II), cobalt(II) nickel(II), copper(II), thorium(IV) and
uranyl(II). Different standardized instruments as spectral (UV-Vis; IR)
methods, elemental analyses, magnetic moment, molar conductivity
measurements, thermal (TG/DTG) technique, electron paramagnetic
resonance (EPR) spectra and X-ray diffraction (XRD) patterns were used
for characterization of the structure of the synthesized ligand as well as its
corresponding metal complexes. The ligand and its metal complexes have
also been screened for their antibacterial and antifungal activities against
pathogenic bacteria and fungal strains. Some selected complexes
(2B,4B,6B) were subjected to gamma irradiation to a dose of 100 kGy
and at a dose rate of 2.2 kGy h-1. The FT-IR, UV–Visible absorption
spectra, molar conductivity, magnetic susceptibilities and thermal
analysis (TG/DTG) for the irradiated samples were obtained. X-ray
powder diffraction technique of the unirradiated and irradiated samples of
complexes were carried out. Electron paramagnetic resonance (EPR)
spectra were carried out for one of the copper(II) complexes before and
after irradiation.
The third Chapter: - Results and discussion
This chapter includes the results obtained and their discussion and
includes the following: -
(i) Synthesis and characterization of ligand (L): N,N-((Z)-ethane-1,2-
diylidine)bis(2-aminobenzohydrazide) and its Mn(II), Co(II),
Ni(II), Cu(II), Th(IV) and UO2(II) metal complexes.
(ii) characterization of the obtained compounds was achieved by
using different analytical and spectroscopic tools such as {IR;
UV/ Vis}, molar conductance, magnetic moment measurements
and thermal analysis (TG/DTG) technique. X-ray diffraction
(XRD) patterns and electron paramagnetic resonance (EPR)
spectra have also been carried out for some selected complexes to
substantiate the proposed structure. Also, selected complexes
(2B,4B,6B) indicated after irradiation as (2A,4A,6A) were
irradiated by γ-rays at a dose of 100 kGy and at a dose rate of 2.2
kGy h-1 by using Indian 60Co γ-ray cell type GE-4000 A under
room temperature. from the obtained results we have reported
the following remarks:
1. The complexes are air stable, non-hygroscopic and are slightly
soluble in alcohols, insoluble in most common organic solvents.
but, they are soluble in DMF or DMSO solvents.
2. The results of elemental analyses showed that all complexes are
formed in molar ratio (1M:1L) except for complex (4) that is
2M:1L and complex (8) that is 1M:2L.
3. The molar conductivity values for metal complexes show that all
complexes are non-electrolytes except complex (7) that is 1:1
electrolyte and complex (8) is 1:2 electrolyte.
4. IR spectral studies of ligand (L) showed that the ligand exhibits
interesting coordinating ability to the different metal ions and
behave as a neutral tetradentate or bidentate one or as dibasic
tetradentate.
5. The electronic absorption spectra and magnetic susceptibility
measurements proved that all metal complexes have distorted
octahedral geometry except complex (4) that adopt tetrahedral
geometry.
6. The EPR spectrum of Cu(II) complex (6B) in powdered form
indicated axial spectrum with dx2- y2 ground state of Cu(II) ion.
7. The thermal behavior of metal complexes shows good agreement
with the formula suggested from the analytical, spectral and
magnetic data. The decomposition temperature lies in the range
(136-235 °C) for metal complexes.
8. X-ray powder diffraction (XRD) patterns of complexes
(2B,4B,6B) showed that these complexes are amorphous.
By comparing the results of molar conductivity, FT-IR, UV-Vis.
absorption spectra, TGA, XRD and EPR studies of unirradiated and
irradiated we can outline the following remarks:
1- Molar conductivity of iradiated complexes slightly changed after
irradiation.
2- Position, shape and intensities of IR peaks of some functional
groups as (C=N), (C=O) in irradiated complexes slightly
changed after irradiation.
3- No new peaks were observed in UV–Visible spectra after
irradiation, but a slightly change in the intensity as well as
position of d-d bands were observed. Also, magnetic moments of
irradiated complexes showed slight changes after irradiation.
Thus, there was no change in the geometry complexes after
irradiation.
4- UV–Vis spectra, magnetic moments and Electron paramagnetic
resonance (EPR) spectrum of Cu(II) complex (6A) after
irradiation indicated its octahedral geometry with dx2- y2 ground
state.
5- TGA results indicated slightly change in dehydration temperature
and thermal decomposition of irradiated complexes.
6- X-ray diffraction (XRD) patterns studies indicated no change in
the XRD patterns of complexes after irradiation and that the
unirradiated and irradiated complexes are amorphous.
(iii) The ligand and its all metal complexes have been screened against
pathogenic bacteria and fungal strains for testing their
antimicrobial activity, The antimicrobial studies results showed
that these compounds exhibit a moderate antibacterial and
antifungal activity, and that:
1. Mn(II) complex was the most potent one, it showed higher
antibacterial activity than the free ligand with respect to gram
positive (Staphylococcus aureus) at both concentration (20, 10
mg/ml). Also, Ni(II) complex showed higher antibacterial activity
than the free ligand with respect to gram positive at both
concentration.
2. Although the ligand has no antifungal activity, complexes (2A,3)
exhibited moderate activity at low concentration (10 mg/ml) and
complex (7) exhibited activity at high concentration.
3. Antimicrobial activity of tested complexes is higher than that of
the free ligand, which implies an increase in the antimicrobial
activity with chelation/coordination.