الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
This thesis discusses the issue of absorbent surfaces used in the field of solar thermal energy and the method of manufacturing an absorbent surface from only one component instead of the traditional method that depends on the presence of a substrate and selective coating, using the wastes of cement factories, which have a harmful effect on the environment and it is backfilled in the ground at an additional cost.
A large number of researches concerned with the study of selective surfaces have been reviewed to know the best techniques used, as well as the methods of preparing glass and the characteristics of a number of types of glass. Accordingly, the materials needed to manufacture the studied glass samples, consist of residues of cement factories with adding glass forming materials like sand. In this mixture the waste of cement factories represents approximately 25% of the compounds needed to form glass.
After manufacturing the basic sample of glass, free of any additives, it turned out to be a very transparent sample, which makes it not suitable to work as an absorbent surface. Therefore, some components had to be added to make the sample completely opaque, and based on it, cobalt and basalt were added to the composition for the manufacture of glass. The samples were melted and the percentage of each addition was increased to reach full opacity and the optical properties of the resulting samples were studied. A heat treatment was also used for one sample of glass until the glass turned into ceramic, thus ensuring the required complete opacity.
After doing the necessary tests on the samples, it was found that the cobalt group will not reach the required opacity, as cobalt is a coloring element only, while the basalt group has reached the best opacity than adding basalt 30% and basalt 40%, and the results of their optical properties were very promising, as the absorbance of Basalt 40% reached to 97% and emissivity 5% emissivity on the polish surface, while 94% absorbance and 4% emissivity on the rough surface. Sample basalt 40% was also heat treated, and it was found that the quality of the absorbent surface decreased, as the absorbance reached 97% and the emissivity 7%.