الفهرس 
Literature Survey on the PreparationOnly 14 pages are availabe for public view
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Abstract
SUMMARY
This thesis consists of three main chapters.
Chapter 1, the introduction:
In which a general introduction on the importance of nano materials and their applications in different fields is presented. This chapter also includes a literature survey on the previous work performed on the structure elucidation of nano particles, biological applications and removal of different organic pollutants from water samples.
Chapter 2, the experimental:
This chapter includes complete description of the materials and methods used for the preparation of silver nano particles . This chapter also describes the instrument used in characterization of the prepared samples such as uv-visible spectro photometer, X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and Fourier Transform Infrared spectra (FTIR).
Chapter 3, results and discussion:
In which the results obtained throughout the work are presented and discussed. It is subdivided to three main parts as follows:
Part 1:
Describes the synthesis and characterization of silver nano particles prepared from AgNo3 and mango leaves extract ,the brownish color of Ag nano particles due to excitation of surface plasmon vibration and reduction of Ag+ to Ago , formation of silver nano particles and study of different parameters as temperature ,PH, time, concentration of AgNo3 and amount of mango leaf extract which affects on formation of silver nano particles. The prepared nanoparticles were characterized as follows:
1- UV–Vis spectra analysis.
The synthesis of Ag NPs confirmed by UV –Visible spectro photo meter (430-466) the increase of the absorbance intensity of the reaction with time and the solution was stable after 60 min. of incubation.
2- FTIR spectra.
Disapperance of bands after reduction of Ag+ to Ago in the spectra of the brownish solution due to polyols are mainly responsible for the reduction of Ag+ ions. Oxidation to un saturated carbonyl groups leading to abroad peak at 1660 cm -1 (for reduction of Ag).
3- The XRD pattern.
Used to characterize the phase purity, nature,crystallographic structure and estimate for the particle size of the examined materials by scherrer equ.. The XRD peaks are broadened due to the nano crystalline nature of the particles.
4- The HRTEM.
The morphology and particle shape of the as-prepared samples were studied by high resolution transmission electron microscopy (TEM) by dispersed sample in ethanol on a copper grid. the synthesized Ag nanoparticles are spherical in shape. The average size estimated was 35 nm and the particle size ranged from 6 to 50 nm.
Part 2
Includes the biological applications of the prepared Ag Nps:
1- The antimicrobial activity of Ag Nps was tested against representatives of Gram – positive bacteria (Streptococcus pyogenes and Staphylococcus epidermidis) and Gram – negative bacteria (Proteus vulgaris and Klebsiella pneumonia). Standard drug; ampicilline separately for their antibacterial activity. The antibacterial results suggest that the as prepared silver nano particles show high activity against the tested organisms.
2- The enhanced activity of silver nano particles may be attributed to the increase in penetrating process taking place through the cell walls.
Part 3
Includes the analytical applications in the field of water treatment. Silver nano particles was tested as catalyst for the removal of bromo cresol purple dye and malachite green dye from water samples. The as-prepared silver nano particles showed high efficiency in this process. The kinetics and thermodynamic parameters of the process were determined.