The increasing demand for sustainable construction materials has prompted the recycling of construction and demolition waste in concrete manufacturing. This study investigates the feasibility of utilizing porcelain and brick waste as partial substitutes for natural sand in concrete with the objective of improving sustainability and preserving mechanical and durability characteristics. The experimental program was conducted in three consecutive phases. During the initial phase, natural sand was partially substituted with porcelain waste powder (PWP) and brick waste powder (BWP) in proportions of 25%, 50%, and 75% of the weight of the fine aggregate. During the second phase, polypropylene fibers were mixed at a dosage of 0.5% by volume fraction to enhance tensile and flexural properties. During the third phase, zinc oxide nanoparticles (ZnO-NPs) were utilized as a partial substitute for cement at concentrations of 0.5% and 1% to improve microstructure and strength progression. Concrete samples were tested at curing durations of 7, 28, and 91 days. The assessed qualities encompassed workability, density, water absorption, porosity, compressive strength, flexural strength, and splitting tensile strength. Microstructural characterization was conducted utilizing X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The findings indicated that porcelain waste powder markedly surpassed brick waste powder in all mechanical and durability-related characteristics, particularly at 25% and 50% sand replacement ratios. The integration of polypropylene fibers enhanced fracture resistance and ductility. Moreover, the incorporation of zinc oxide nanoparticles improved hydration, optimized the pore structure, and resulted in significant enhancements in compressive and tensile strength throughout prolonged curing durations. The best results were obtained with a mix of 50% porcelain sand aggregate, 1% zinc oxide nanoparticles as cement replacement, and 0.5% polypropylene fibers, for which the improvements in compressive strength, flexural strength, and splitting tensile strength were 39.5%, 46.2%, and 60%, respectively, at 28 days. The results confirm the feasibility of using porcelain and brick waste as sand replacements in concrete, as well as polypropylene fiber-reinforced concrete and polypropylene fiber-reinforced concrete mixed with zinc oxide nanoparticles as a sustainable option for construction purposes.

The feasibility of waste collection strikethrough in the traditional evaporation deposition system after preparing thin films was investigated. In this paper, first, the Selenium thin films of 0.5 μ m thickness were prepared by a thermal vacuum evaporation system and an evaporation assisted laser Neodymium - Yag pulsed Nd:YAG laser system. Then, the waste materials that remain in the systems were collected and examined. The inspections include the particle size and other structural properties, taken before and after annealing at 300 °C for 30 min. Results show that the prepared thin film and particles are crystalline and the particle size of collected particles are in the range of about <50 nm, which makes this method very useful in the production of recycled nanoparticles of metals and materials that are costly or harmful, but can be an advantage and beneficial.

Copper oxide CuO and Magnesium oxide MgO are considered among the most promising oxides in the current development. Nanocomposite particles NCPs of MgO-CuO were synthesized by using the sol-gel method. The copper (II) nitrate trihydrate 0.1M and Magnesium nitrate hexahydrate 0.1M solvents were mixed at a 1:1 ratio and the gel was formed at a temperature of 80 °C, then dried calcined at 500 °C for different time (3, 5, and 7 hours). The CuO/MgO particles were characterized by particle size analyzer (PZA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and apparent density. The result of x-ray diffraction proved the phases purity of the composite particles. On the other hand, FESEM images proved nanoparticles embedded in the MgO-CuO matrix with a particle size of 33.5 –63.27 nm. Moreover, the density for the above samples was 0.699, 0.721, and 0.755 g/cm3 respectively. It increases with increasing the calcined time. This stimulates the growth of crystals CuO/MgO which exhibits excellent catalytic activity for the advanced application.