الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The problem of water pollution is one of the most important problems
that we face because of its harmful effects on public health and the
environment. Studying some of these pollutants using new electrodes.The aim
of this thesis were developed to the design of a novel electrode as were
described consisting of pDAAQ/pDAN@GCE, pDAN/pDAAQ@GCE and
molybdate/ pDAN/pDAAQ@GCE composite electrodes by electropolymerization
method using CV. This developed composite electrodes were
applied for improved simultaneous determination nitrite and phosphate ions.
The thesis consists of three chapters as follows:
Chapter one : This chapter focused on general background of modified
electrodes, how to modify electrode surface electro-chemically and the
conducting polymers with special focus on poly diaminonaphthalene and what
makes polymers conductive? their synthesis by introducing highlights about
both chemical and electrochemical polymerization and its applications. Also I
paid a great attention to general description of nitrite “Identity, properties of
nitrite, uses of nitrite and adverse effect of it in food and drinking water and
different methods of detection nitrite” .
Finally of this chapter I introduced a general background about phosphate
general description of it, An important occurrence of phosphates in biological
systems, geological occurrence and electrochemical Phosphate detection methods.
Chapter two : This chapter reported the experimental part which mainly
stated with electrochemical preparation of pDAAQ/pDAN@GCE and pDAN/
pDAAQ @GCE composite electrodes via CV at GCE using a 1.5x10-3M DAN
solution in 1.0 M HClO4. Its activity was recorded in a CH3CN solution
containing 0.1 M LiClO4 for 15 cycles at a potential range of 0.0–0.8 V and a
scan rate of 0.02 V s−1 .
Summary
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Similarly, pDAAQ was synthesized via CV at GCE using a 0.1 M DAAQ
monomer solution in 1.0 M HClO4, and its activity was recorded in 0.1 M
LiClO4/CH3CN for 15 cycles in a potential range of 0.2–1.4 V at ʋ 0.5 V s−1.
To produce the pDAAQ/pDAN@GCE and pDAN/pDAAQ@GCE
composite electrodes, pDAAQ/pDAN and pDAN/pDAAQ were deposited layer
by layer using the same procedure.
Also reported about electrochemical preparation of Molybdate/
pDAN/pDAAQ@GCE composite electrode was prepared via CV method
between of -0.5 and 0.5 V vs. Ag/ AgCl in 0. 1M [(NH4)6Mo7O24.4H2O]
solution for 10 scanning cycles at a scan rate of 0.1 Vs-1 on the surface of
pDAN/pDAAQ@GCE composite electrode and supporting electrolyte 0.1 M
H2SO4,and also reported about preparation of real samples.
Chapter three: Part I: This chapter disclosed the characterization of
pDAAQ and pDAN were electrochemically deposited layer by layer on a GCE
to generate pDAAQ/pDAN@GCE and pDAN/pDAAQ@GCE composite
electrodes, respectively. The morphology and characteristics of the modified
electrodes were investigated via EIS, FT-IR, and SEM. The obtained results
reveal the outstanding performance of the pDAN/pDAAQ@GCE electrode for
electrochemical nitrite sensing where pDAAQ plays a vital role as the inner
layer. CV, LSV, and DPV measurements revealed that the oxidation peak
current of nitrite was proportional to its concentration.
Part II : The molybdate/ pDAN/pDAAQ@GCE underwent CV in a
solution of 0.1M NaOH, and repetitive scanning was used to assess the
formation of MoO4
2−, where the phosphomolybdate complex was formed under
acidic conditions. Molybdate/ pDAN/pDAAQ@GCE composite electrode can
use for electrochemical detection PO4
3- using LSV after determine the
Summary
74
optimize conditions of analytical, Some factors that affect the oxidation
behavior of phosphate ions have also been studied