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Composites have been found to be the most promising and discerning material available in this century. Fiberreinforced plastic is a composite material wherein a polymer is reinforced with fibers to enhance or add properties. These fibers are typically glass or carbon, although aramid, basalt, and even wood and paper have been used. Fiber reinforced plastics are commonly used in aerospace, automotive, marine, and construction industries because of their corrosion resistance and low weight-to-strength ratio.In this work, the effect of acidic , alkaline and neutral mediums on the PVC / PVC sandwich plates with 0.95 Wt. % glass fiber blended with different types of adhesive materials (epoxy, polyester and poly vinyl acetate) were studied deeply. Different pH values (3, 5, 7, 9 and 11) as well as three time of exposure (2 hrs., 4 hrs. and 6 hrs.) were adopted. The mechanical properties of the PVC / PVC sandwich plates with glass fiber blended with different types of adhesive materials such as tensile strength, ultimate strength, modulus of elasticity, energy to fracture, impact energy and adhesion shear at different pH values were studied.It has been found that the mechanical properties of PVC / PVC sandwich plates with 0.95 Wt. % glass fiber blended with different types of adhesives decrease with increasing the time in both strong alkaline medium, acidic medium and is constant in neutral medium.

The chemical composition of corn stalk as well as fiber morphology, fiber length and diameter were carried out. Furthermore, Kraft pulping process using different cooking conditions (temperature, 125 -170ºC, time, 15 -40 min., and % alkali 9 -12%) were done at laboratory scale. The obtained pulps were characterized with respect to %yield, %rejects, kappa number and rest alkali. Effect of chemical composition of corn stalk on yield and kappa number was discussed.The mechanical properties of hand sheet paper were explained in details, according to different cooking conditions. The high ash content and the relatively short fiber of corn stalk can attribute to positive effect with respect to bulk, opacity and the necessary strength of paper which are important properties in newspaper. Industrial trials were carried out using Pandia continuous digester (74 tons corn stalk kraft pulp was produced) and 90 tons newsprint paper (furnish: 86.5% bleached corn stalk pulp + 13.5 bleached soft wood pulp) was obtained using Furdirinier paper machine. The produced newsprint was printed and commercialized by four famous newsprint companies in Cairo -Egypt (about twenty tons for each).Comparison with the imported newsprint paper was done, the produced newsprint has better qualities with respect to opacity, and strength properties. Findings from industrial and commercialized trials in this study provide insights into new opportunities to utilize corn stalk pulp as better alternative to produce good quality of newsprint.

General strategy of this study was based on the operational parameters influencing the photo-catalytic degradation rate of oil polluted wastewater treatment. Titanium Dioxide doped nanofibers (TiO2NFs) with different parameters that affect the photo-catalytic degradation process for oily wastewater were investigated. These parameters are initial oil concentration, catalyst loading and pH . Emulsifier was used in all experiments to increase the solubility of oil in water. Maximum oil removal (81.8%) and (66.2%) decrease in COD was found when the oil initial concentration is 800 ppm, 0.5 g of TiO2NFs at 180 minutes irradiation time using solar photocatalytic oxidation technique. Small size of TiO2NFs particles and its high specific surface and surface energy result in the catalyst agglomeration during the reaction. It causes the reduction of specific surface and limits the multiple application of (TiO2NFs). It is concluded that nanofibers remarkably enhanced TiO2 (without doping) catalyst activity in the removal of oil by solar photo-catalytic oxidation. Since, nanofiber is highly adsorptive, this enhanced activity could be relieved to the adsorption of nanofiber. Suitable adsorption capacity is crucial for high photo-catalytic activity. Moreover, the process should be improved in the field of catalyst photo-activity range or the possibility of integration into photo-catalytic reactors.

The role of electromagnetic field (EMF) in enhancement of copper (II) removal from industrial wastewater effluent has been investigated. The rate of copper (II) removal from industrial wastewater by cementation on rotating iron cylinder subjected to a magnetic field was studied to demonstrate the effect of EMF on the rate of cementation. The results proved the enhancement of copper removal by utilization of EMF; however the effect of decreasing the thickness of boundary layer is more dominant than the effect of EMF. The rate of mass transfer was correlated by the equation sh=2.3 Re 0.95 Sc 0.33 .Another correlation provides the relation between mass transfer coefficient and the other operating variables namely: intensity of EMF, initial copper concentration and rotation speed of iron cylinder k=exp(1.4*10 -3 *N+1.2*10 -3 *C o +4.1*10 -4 *H -0.5). This work illustrates that the enhancement of copper recovery in presence of EMF is due to the induced motion of paramagnetic Fe +n in the solution and is limited in the range of cylinder rotation speed of 300~900 rpm. It was evident that power consumption due to utilization of magnetic field is less by 3% than that without utilization of EMF.