From several points of view, disposal of waste materials in an environment is respected to be a significant problem because of its very low biodegradability and existence in huge quantities. Waste of plastic and metal bottles caps, cans of juices and soft drink, and tires rubber being among the most pronounced. This study was conducted to evaluate the efficiency of reusing these waste materials in concrete production and solve the segregation problem. As segregation increases in concrete involving these waste materials due to lighter weight of them relative to nature aggregate, therefore, attention was intensive on using natural product (Gum Arabic) that is an environmentally friendly chemical material for improving concrete properties. The conducted tests include; compressive strength, flexural strength, splitting tensile strength, density, water absorption, and ultrasonic pulse velocity. The results showed that replacing the volume of coarse aggregate by 25% compacted bottles caps and pull-tab of cans, 20% the plastic bottle caps, and 25% tires rubber shreds used decreased the mechanical properties of concrete to some extent less than reference mix and they were enhanced by employing Gum Arabic. In addition, the employment of Gum Arabic as liquid in concrete mixes developed the mechanical properties of concrete, reduced segregation, however raised the water absorption percent and declined the density of concrete.

This work focuses on investigating the behavior of micro and nanoFe2O3 in concrete through the study of microscopy, compressive strength and flexural strength. Seven mixes of concrete are prepared. Three of which include micro Fe2O3 comprising 1%, 3% and 5% as partial substitutions of cement weight and the other three mixes containing 1%, 3% and 5% nanoFe2O3 as a partial substitutions of cement weight, as well as the reference mix. SEM study exhibits that the microstructure of sample produced with micro Fe2O3 show more uniformity and dense compared with reference sample. However, existence of micro cracks in the microstructure in mixes with micro Fe2O3 is clear especially with increasing micro Fe2O3 content to 3% and 5%. In mixes with nanoFe2O3, the new shapes of needle like crystals and flower like crystals can be distinguished. The presence of these types of crystals in thrives amount approve that nanoFe2O3 producing new phases of gel. Hence, the microstructure of samples is condensed, and with the increasing of nanoFe2O3 content the microstructure is completely compacted. The results of compressive strength and flexural strength showed that the mechanical properties are related to microstructure properties. When micro Fe2O3 is used, the mechanical properties drop obviously. While, the mechanical properties are improved in mixes containing nanoparticles in comparison with the control mix.

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The conversion of saltwater and brackish water into fresh water through desalination has gained significant importance as a solution to the worldwide scarcity of fresh water resources.  The Reverse Osmosis (RO) method has been effectively utilized to generate fresh water from sources of brackish water. This research aims to examine the variables that affect the performance of the reverse osmosis process. The effectiveness of the membrane was assessed through experiments that explored the impact of varying operating conditions, such as feed pressure, temperature, and concentration, on the reverse osmosis pilot plant and salt solution system (consisting of NaCl and MgCl2). The selected membrane used a polymeric membrane constructed as FilmTec TW30-1812-50 spiral-wound module. The results showed that as the feed temperature and salt concentration increased, the salt rejection decreased. On the other hand, as the transmembrane pressure was raised, the membrane's salt rejection improved. The experiments revealed that the feed temperature and salt concentration have a significant impact on the membrane's performance. Among the various variables studied, operating pressure had the largest effect on the product rate. As operating pressure increased, the permeation flux and salt rejection also increased, with a salt rejection rate of 96% achieved at 5 bars. In addition to other factors, the concentration of the feed greatly influences the solute content in the final product.