الفهرس 
Chapter1: IntroductionOnly 14 pages are availabe for public view
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Abstract
The thesis consists of four chapters as follows: Chapter 1: presents history of nanoparticles. we also show the Effect of particle size on Physical Phenomena, the Applications of nanoparticle, Uses of nanoparticles in catalysis, Synthesis of nanoparticle, nanocomposites, synthesis methods of nanocomposite and nanorods. Chapter 2: includes Literature survey about PVA/Ag Nanocomposites and Gold Nanorod Using Seed-Growth method. Chapter 3: shows two parts:- Part I: synthesis and characterization of PVA/Ag nanocomposites using gamma irradiation, firstly Preparation of the PVA/Ag nanocomposites secondly determination of Gel content% thirdly catalytic reduction of 4-nitrophenol Part II: Synthesis and characterization of Gold Nanorod Using Seed-Growth method; starting with synthesis of Au NPs then synthesis of the growth solution Chapter 4: include two parts :- Part I: synthesis and characterization of PVA/Ag nanocomposites using gamma irradiation:- we prepare PVA/Ag nanocomposite film from an acidified solution of PVA and AgNO3 which is casted and left to dry. At this stage, the silver ions were not reduced within PVA matrix Part II: Synthesis and characterization of Gold Nanorod Using Seed-Growth method;- Our visual observations during the preparation of gold nanoparticles also indicated that [AuCl4]– interacts with CTAB before the reduction process is induced. Upon addition of CTAB to the pale-yellow solution of HAuCl4, orange color precipitate forms. As the concentration of CTAB increases, the precipitation disappears and the color of the solution becomes orange. It is well known that by mixing HAuCl4 solution with different surfactant, the peak position is shifted depending on the interaction between the surfactant and [AuCl4]–. Therefore the complex can be characterized by the peak shift. The visual inspection for the preparation process of the seed solution indicated that there is an instant color change from yellowish orange of (HAuCl4/CTAB) to reddish brown upon NaBH4 addition. In the seed-mediated method, ascorbic acid (AA) is used as a mild reducing agent. When the stoichiometric ratio of AA was added without seed solution, there was no color change for 24 hrs. But when the solution was kept for over a week, pale purple color developed. But UV-Vis spectrum shows no significant nanoparticles formation. Only when AA was added to seed solution, Au nanoparticles were produced as a main product. In order to obtain non-agglomerated metal particles with a well defined shape: nucleation and growth must be two completely separated steps.