الفهرس 
INTRODUCTION and LITERATURE SURVEYOnly 14 pages are availabe for public view
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Abstract
SUMMARY
The thesis consists of three chapters besides Arabic and English
summary. Chapter one is about general introduction to nano materials, their
properties, methods of preparation, properties of used materials in the thesis,
solvation, ion solvation, solubility, factors affecting solubility, applications of
conductivity, densities and volumes. Also this chapter contains some
literature survey of published paper in the area of the thesis.
Chapter two is the experimental part, explains the chemical used and
their properties, instruments used for measurements like X-ray diffraction,
transmittion electron microscopy, infra-red spectra photometer (FTIR),
conductivity bridge and preparation of nano-barium carbonate, nano-copper
carbonate and nano-zinc carbonate. Also the preparation of solutions and
conductivity measurements are also given in this chapter.
Chapter three is the results and discussion. It divides into three parts.
Part one is about, solubility, density and conductivity measurements for
nano-barium carbonate in mixed DMF – H2O solvents ( 50, 60, 70, 80, 90
and 100 % ) by volume at four temperatures ( 292.15, 303.15, 308.15 and
313.15K ).
The solubility parameters, molar solubility, activity coefficient,
solubility product and dissolution free energy for nano-BaCO3 were evaluated
from solubility measurements and it was found that all increased by the
increase in both the mole fraction of DMF in the mixtures and temperature
due to more salt – solvent interactions.
All types of volumes calculated from densities measurements for
nano BaCO3 in mixed DMF – H2O solvents were evaluated from density
measurements which are, molar volumes (VM), Van der Waals volume (VW),
and electrostriction volume (Ve). All volumes for nano-BaCO3 are increased
by the increase in both temperature and proportion of DMF favouring more
solvation.
from conductivity measurements and from the relation between
molar conductance and (C1/2), the association thermodynamic parameters for
nano-BaCO3 alone were evaluated and include the association constant,
degree of dissociation, association free energy, enthalpy of association and
entropy of association at different temperatures and in mixed DMF – H2O
solvents. The association parameters obtained for nano-BaCO3 alone are
increased by the increase of both mole fraction of DMF and temperature.
This solvation association process is enthalpic and not entropic (depend only
on enthalpy).
The association parameters obtained for nano-BaCO3 with ligands
bromophenol blue and cresol red were evaluated and found to be greater in
case of interaction of nano-BaCO3 with bromophenol blue than those with
cresol red at all DMF percentages and all temperatures.
The complex formation parameters for forming 1:2 and 1:1
stoichiometry complexes, found in the relation between molar conductance
and the ratio of metal to ligand concentration, are estimated from
conductance titration measurements between the nano salt and the ligand.
The formation of 1:2 and 1:1 stoichiometry complexes are detected from the
relation of molar conductance with [M]/[L].
The formation constants and Gibbs free energies of formation for the
interaction of nano-BaCO3 with both bromophenol blue and cresol red have
greater values in forming 1:1 [M/L] stoichiometry complexes than 1:2 ones
indicating more possibility to happen. It was found that the complex
formation parameters for interacting nano-BaCO3 with cresol red forming 1:2
and 1:1 complexes have greater values than those in case of bromophenol
blue at all temperatures and mixed DMF – H2O solvents.
The enthalpies calculated from the relation between log Kf and 1/T
support the above trend together with entropies evaluated from Gibbs –
Helmholz equation.
Part two is about , solubility , density and conductivity measurements
for nano copper carbonate nano-CuCO3 in mixed DMF – H2O solvents ( 50,
60, 70, 80, 90 and 100 % ) by volume and at four temperatures ( 292.15,
303.15, 308.15 and 313.15K ).
The solubility parameters, molar solubility, activity coefficient,
solubility product and dissolution free energy for nano-CuCO3 are increased
by increase of the mole fraction of DMF in the mixtures and increase of
temperature indicating more solvation.
All volumes evaluated from densities measurements for nano-CuCO3
solutions increased by increasing percentage of DMF favouring more
interaction between the salt and mixed DMF – H2O solvents used.
from conductance measurements and from the relation between
molar conductance versus (C1/2) for nano-CuCO3 solutions alone, the
association constants and Gibbs free energies of association are increased by
increasing temperatures and volume percentage of DMF in the solutions.
In absence of ligands and from the slopes of relation between log KA
and reciprocal of temperature , the enthalpies of association were estimated
and found to decrease with increase in temperature which means more
solvation also. The entropies calculated from Gibbs – Helmholz equation
support this behavior.
The complex formation constants and energies for forming 1:2 and
1:1 [M/L] complexes evaluated from conductance titration and molar
conductance versus concentrations [M/L] gave greater values for the
interaction of nano-CuCO3 with cresol red than those of nano-CuCO3 with
bromophenol blue, indicating greater ability to use nano-CuCO3 with cresol
red in all the used mixed solvents and at all temperatures.
The solvation of nano-CuCO3 with the ligands bromophenol blue and
cresol red are exothermic (negative enthalpy) from the slopes of the relation
log KA and 1/T and small positive entropy data (calculated from Gibbs -
Helmholz equation).
Part three is about , solubility , density and conductivity
measurements for nano-zinc carbonate in mixed DMF – H2O solvents ( 50,
60, 70, 80, 90 and 100 % ) by volume and at four temperatures ( 292.15,
303.15, 308.15 and 313.15K ).
The solubility parameters for nano-ZnCO3 are increased by increase
of both temperature and mole fraction of DMF.
All volumes for nano-ZnCO3 in the used solutions were calculated
from density measurements and found to increase with the increase in both
temperature and percentage of DMF due to more salt – solvent interaction.
All enthalpies (positive values) and entropies (positive values) of
dissolution for saturated nano-ZnCO3 solutions are decreased by increasing
DMF mole fraction indicating easier solvation.
The association thermodynamic parameters for nano-ZnCO3 alone
evaluated from conductance measurements are decreased with the increase in
both temperatures and DMF percentage favouring less solvation. The
estimated thermodynamic association parameters for nano-ZnCO3 with both
ligands ,bromophenol blue and cresol red, are increased by increase in
temperature and percentages of DMF favouring more aggregation .Cresol red
gave bigger association parameters with nano-ZnCO3 than those with
bromophenol blue in all mixed DMF – H2O mixtures and at all temperatures.
The complexes formed are proved to be 1:2 and 1:1 stoichiometry
complexes for the interaction of nano-ZnCO3 with both bromophenol blue
and cresol red in all solutions. All the complex formation parameters for
interaction of nano-ZnCO3 with ligands are greater for 1:1 complexes
thanthose for 1:2 complexes.
The complex formation parameters are greater in using cresol red
with nano ZnCO3 than those of bromophenol blue with nano-ZnCO3 in the
different solutions. All complexation in case of using nano-ZnCO3 are
enthalpic and entropic solvation process.
All solubility data, volumes, conductance association thermodynamic
parameters without and with both bromophenol blue and cresol red for the
three nano salts show the following order:
Nano-BaCO3 > nano-CuCO3 > nano-ZnCO3
The complex formation parameters forming 1:2 and 1:1 complexes
with the interaction of the three nano salts with ligands (bromophenol blue
and cresol red) have the following order:
Nano-ZnCO3 > nano-CuCO3 > nano-BaCO3
The thesis gives a lot of data which help in evaluation of different
salts (nano-BaCO3, nano-CuCO3 and nano-ZnCO3) in presence of two
ligands (bromophenol blue and cresol red