In Iraq, a large quantity of basic orange and methyl violet dyes contaminated wastewater from textile industries is discharged into Tigris River. So the aim of this work is to found an efficient and fast technique that can be applied directly for removal of such dyes from the wastewater before discharging into river. Accordingly, CNTs as a new approach prepared by CCVD technique were purified, functionalized, and used as adsorption material to remove dyes from wastewater. The effect of pH, contact time, CNTs dosage, and dyes concentration on removal of pollutants was studied. The removal percentage of both dyes was proportional to the contact time, CNTs dosage, and pH and inversely proportional to the dyes concentration. The results show that the equilibrium time was 20 and 30 min for basic orange and methyl violet dyes, respectively, and the maximum removal percentage for all dyes concentrations was at pH = 8.5 and CNTs dosage of 0.25 g/L and 0.3 g/L for methyl violet and basic orange dye, respectively. The adsorption isotherm shows that the correlation coefficient of Freundlich model was higher than Langmuir model for both dyes, indicating that the Freundlich model is more appropriate to describe the adsorption characteristics of organic pollutants.

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Diglycidyl ether of bisphenol A (DGEBA) epoxy resin was cured with hardeners aliphatic amine triethylenetetramine (TETA). Differential scanning calorimetry (DSC) technique was utilized to study the kinetics of cure of (DGEBA)-(TETA) system, diverse hardener/resin ratios were studied, (5, 13and 20) phr. Isothermal as well as dynamic experiments were carried out of the above mentioned DGEBA/TETA system with three hardener/resin ratios, and cure kinetics were investigated at four temperatures (30, 45, 60 and 80) °C using (DSC) technique. The process of isothermal cure was simulated by the diffusion model (modified Kamal's model and four-parameter autocatalytic model. The obtained outcomes are in good agreement with the experimental results in the early and late cure stages. The events declare that complete cure at 80 °C attains at the stoichiometric ratio (13 phr).

Heat transfer process involved in the autoclave curing of fiber-reinforced thermosetting composites is investigated numerically. A model for the prediction of the temperature and the extent of the reaction across the laminate thickness during curing process in the autoclave of unsaturated polyester based composite has been developed. The governing equation for one dimensional heat transfer, and accounting for the heat generation due to the exothermic cure reaction in the composites had been used.  It was found that the temperature at the central of the laminate increases up to the external imposed temperature, because of the thermal conductivity of the resin and fiber. The heat generated by the exothermic reaction of the resin is not adequately removed; the increase in the temperature at the center increases the resins rate reaction, which in turn generates more heat.

The present work aims to study the degradation of mefenamic acid (MFA) in synthetic wastewater experimentally and numerically. The experiments were carried out using utilizing homemade Cu doped TiO2 in a solar irradiated falling film reactor. Two operating variables are investigated; pH of the wastewater in the range of (3-10) and synthesis wastewater flow rate (1-3 L/min). The numerical study involves the optimization of the variables. The multifactorial design method, Design of Experiments (DOE), and Response Surface Methodology (RSM) were used to evaluate the interaction effect of the two variables on the degradation of mefenamic acid. The significance of 0the results was evaluated by statistical analysis of variance (ANOVA). The results show that the removal efficiency increasing with increasing pH and decreases with wastewater flow rate. The results have shown that the interaction effects between mentioned factors were highly significant in influencing MFA degradation by analyzing statistics and ANOVA.