الفهرس 
Nanotechnology challenges for the future.Only 14 pages are availabe for public view
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Abstract
This thesis presents details about synthesis, characterization and some physical properities of gold, silver and copper nanoparticles as well as their composites with SiO2 and TiO2.That will be in details through three chapters. The first chapter represents the introduction involving the nanotechnology challenges for the future and the preparation techniques of metal NPs. It also contains the physical and the chemical methods used for the preparation of metal nanoparticles. The theoretical background of the optical properties of the noble metals including the surface plasmon phenomenon of gold and silver are illustrated. The properties of the capping agent used in this work and the literature survey are also included. The second chapter is devoted to the experimental details involving the materials used in this work and the variable procedure of preparation of gold, silver and copper nanoparticles. Represents synthesis of Au/TiO2 -nanocomposite, preparation of nanosilver using gold seeds, synthesis of Ag-NPs as colorless transparent solution, synthesis of silver/silica nanocomposites, synthesis Cu-NPs by using sodium formaldehyde sulfoxylate (SFS) as a reducing agent. Preparation of nano-Cu at low temperature by using ascorbic acid as reducing agent and CTAB as surfactant & capping agent and preparation of Cu nano-fluids. This section shows the characterization techniques used for the physical and biological studies. The third chapter gives over the results and discussion showing the characterization of the produced materials using different characterization techniques such as XRD, TEM and UV-Visible. It also includes a discussion of some physical properties for the prepared materials involving the optical properties. This chapter discusses the antimicrobial activity of nano-silver samples against seven bacterial strains threewere grame +ve bacteria and four were grame –ve bacteria. The result involves the discussion of the photocatalytic degradation of Methyl orange on nanoAu/TiO2 composite as a catalyst using UV-Visible absorption. It was observed that there are variable parameter affecting the efficiency of the degradation such as pH, concentration of Au/TiO2 and the dye concentration. The presence of Au in the TiO2 structure caused a significant shift in the light absorption of TiO2 towards the visible region. The optimum conditions for MO degradation were found to be 20 ppm of initial dye concentration, 2 g/L of catalyst dose and a solution pH of 7. It was shown that the degradation process kinetics follows a first order relationship. The degradation process is believed to occur through the formation of a dye-catalyst intermediate before getting converted to the colorless end product. The results discussed the various particle sizes and the morphology of the prepared samples using XRD and TEM techniques.