الفهرس 
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Abstract
This thesis dealt with the synthesis of Nano silica compo-sites used in self-cleaning solar mirrors and on its applica-tion on a piece of Parabolic solar mirrors and studying the effect of weather conditions (humidity, temperature, wind speed, pressure, irradiation) on solar mirrors as well as measuring the reflectance of solar mirrors.
The thesis contains three chapters, arranged as fol-lows:
Chapter I: Introduction
The introduction included some scientific heritage including the following topics:
- Solar system
- Solar mirrors
- Solar mirrors corrosion
-Anti-soiling coating
- Fabrication of Superhydrophobic Surface
-Nanotechnology
-Classification of nanomaterials based on their dimen-sions
-Properties of Nanomaterials
-Applications of nanotechnology
-Dis advantages of nanotechnology
-Synthesis of nanoparticles
-Aloe vera plant
- Types of composite materials
Chapter II: The experimental work:-
This chapter includes the effect of weather condi-tions on solar mirrors and the method of preparing the Nano silica composite substance to create a hydrophobic surface. a hydrophobic surface helps clean mirrors and reduce the amount of demi water used in the cleaning pro-cess as well as measurements and experiments that con-ducted during the work. The samples characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spec-troscopy (FTIR), contact angle(CA), atomic force micros-copy (AFM), scanning electron microscopy (SEM), Ener-gy Dispersive X-ray Analyses (EDX), Thermo gravimetric analysis (TGA& DTA) and zeta potential analyses. A dust accumulation characterized by Energy Dispersive X-ray Analyses (EDX) and scanning electron microscopy (SEM). The hydrophobic surface characterized by contact angle, atomic force microscopy (AFM), zeta potential and reflectance. The protective layers characterized by scan-ning electron microscopy (SEM) and Energy Dispersive X-ray Analyses (EDX) before and after exposure to weather conditions.
Chapter III: Results and Discussion
This chapter included the main reasons, which led to the pitting of solar mirrors through:
- Studying the morphology of solar mirrors and exam-ining the painting of solar mirrors’ margins (edges).
- Studying storage conditions of solar mirrors.
- Studying dust accumulation which is present in solar mirrors.
- Studying the weather conditions (humidity, tempera-ture, wind speed, pressure, irradiation) on solar mir-rors.
- A studying of mirror coatings before and after expo-sure to environmental conditions (the temperature, humidity, solar radiation, wind speed, and pressure) and measuring the reflectance of solar mirrors before and after exposure to environmental conditions.
- Evaluation of Nano Silica composites synthesized for self-cleaning of solar mirrors from sodium silicate and Aloe vera gel by sol-gel synthesis of silica nano-particles (Si NPs). Synthesis of hydrophobic surface on solar mirrors for self-cleaning led to decreasing washability time, and increasing the reflectance. Ex-posure to harsh environmental conditions such as temperature, humidity, wind speed, solar radiation, and pressure led to an increase in the rate of corro-sion. All of these factors combined together led to an increase in the rate of acceleration of corrosion. All of this led to a decrease in the efficiency of the mir-ror from the beginning of its storage, which de-creased in reflectivity from 92.5(as a storage mirror) placed in a warehouse characterized by poor storage to 88.4 after placing them on site in environmental conditions. The deterioration in reflectivity and dis-persion of solar radiation when it falls on the mirror, which in turn led to the failure to achieve the desired goal of solar mirrors in the production of electricity.