الفهرس 
صفحة العنوانOnly 14 pages are availabe for public view
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Abstract
The present thesis deals with individual fabrication of AgNPs, AuNPs and bimetallic Ag-AuNPs via an effective, green, in-expensive, simple and reproducible pathway using superior biopolymers. The application of these nanoparticles in catalysis of organic reaction and in biocidal activities was investigated. The represented thesis focused on comparison between mono- metallic nanoparticles and bimetallic nano-alloys based Ag and Au as nano- catalyst in reduction of aromatic pollutants and in biological purposes. The current thesis represents a controllable strategy for studying the anti-pathogenic effects against selected bacterial strains and fungi for silver nanoparticles and .-gold nanoparticles versus their bimetallic nano-alloys spontaneously prepared by the same technique. Spontaneous ingraining of silver and gold based monometallic and bimetallic nano-objects was carried out by employing organic polymer of hydroxyethyl cellulose which was presumed to play the dual role of . nanogenerator and surfactant, via seed mediated growth technique. Revolution of UV-Visible spectroscopy revealed that, the characteristic surface plasmon resonance (SPR) peak for Ag-Au bimetallic nano-alloy was detected at 480-495 nm and X-ray diffraction patterns confirmed the successive role of HEC in generation of bimetallic nanostructures. Transmission electron microscope (TEM) and zetasizer data were detected for clarifying the effect of the polymer concentration, addition sequencing of metal salts in reaction liquor, and reaction temperature on the morphological features and size distribution of the as- produced bimetallic nano-alloy. Referring to zetasizer analyses and TEM micrographs, small sized (10.7 nm) Ag-Au bimetallic nano-alloy was successfully produced by employing HEC as nano-producer. All the generated bimetallic nano- objects exhibited high stability with Pdl ranged in 0.268 - 0.560. The mechani for generation of nanostructures was confirmed according to FT-I R, lHNMR a 13CNMR spectra. In addition to, the current work demonstrate a controlla technique for synthesis of silver nanoparticles and gold nanoparticles versus t bimetallic nano-alloy as homo-genic and heterogenic nanocolloids a monitoring their employment as nano-catalysts. The required nanocolloids w spontaneously in-grained by using carboxymethyl cellulose {CMC} nanogenerator and protector. Revolution of UV-Visible spectroscopic da affirmed that, surface plasmon resonance {SPR} peak characterized for Ag· bimetallic nano-alloys was ranged in 480-495 nm and X-ray diffraction patte also approved the main role of CMC in production of bimetallic nanostructur .o. Transmission electron microscope {TEM} and zetasizer analyses were detected monitoring the effect of reaction conditions on the topographical features a size distribution of the as-generated nanocolloids. Small sized Ag monometallic 9.7 nm was enlarged to 16.8 - 34.2 nm for Ag-Au bimetallic nanostructures. T catalytic potency of the produced nanocolloids was monitored for the reducti of p-nitro-aniline and the results revealed that, there was a quite stro relationship between catalytic activity and composition of nanocolloids. Halfti of the reduction was sharply decreased from 22.95 to 5.27 min. for monometallic and Ag-Au bimetallic nanocolloids, respectively. Using of t bimetallic nanostructure as nano-catalyst could be beneficial for acceleratingt reduction reaction 23 times.