Heat stabilizer plays a major rule in the manufacturing of plastic products to enhance thermal properties. Carbon nanostructures (include soot) is one of the famous heat stabilizers. In the present study, different ratios of soot were blended to polystyrene (PS) using magnetic-heater stirrer and the ultrasound machine. The casting method was used to prepare the thin films of the pure and blended polystyrene. The techniques such as Fourier Transform Infrared Spectroscopy (FTIR), thermogravimetric analysis (TGA) and UV-Visible spectrophotometer were successfully used to characterize as-prepared composites. TGA results show that the thermal stability of PS is increased significantly after the addition of soot to polystyrene . The initial decomposition temperature (5% weight loss) of PS (229°C) is increased to 395°C when loading 5% (wt/wt) of soot. Differential thermal analysis (DTA) curves of composites represented higher temperature peak 452.23°C, and less degradation rate than virgin polystyrene. In addition, the optical results of polystyrene composite showed decreasing in the energy gap, values of refractive index and the real part of dielectric constant when the soot was added to polystyrene.

In this work, the effect of microwave on asphalt (heating rat, resistance to deformation and retain stability) was examined. Two different asphalt samples were used. The first, standard asphalt (A) and the second one with %2 of sulfur in bitumen (B) have been exposed to microwave. The measured temperature on the surface showed an increase up to 120 ºC in 5 minutes for sample A, while it reached to 145 ºC for sample in the second cycle of exposure to microwave in the same time. The increase rate in temperature for B samples was slightly lower. The presence of sulfur in asphalt reinforced the physical properties and the asphalt became more resistant to water and rutting for sample B after exposure to microwave radiation. Theoretically, the rise of temperature was found to be (0.64 ºC/minute) for one ton of asphalt needing microwave power energy of 1000 watt, but practically, some of this energy loss can be attributed to the conductivity and the penetration of the wave out of asphalt region. This study proved that the better incident angle reducing this loss by using the equation ɵ=sin-1 (x/(1/ α)), and was found to be 28ºC and 37ºC for sample A and B respectively. The results showed the possibility of using microwave radiation in repairing the damaged roads asphalt with economic effective and green method.

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This paper aims to predict the effect of porous media permeability and perforations parameters on the pressure drop and productivity index, for the perforated vertical wellbore with six perforations and for two phase angles. The first 60ᵒ phase angle with helical distribution and the second 180ᵒ phase angle with normal distribution. In this study, a Computational Fluid Dynamics (CFD) software has been used to simulate a model of 3-D turbulent fluid flow with stander k−∈, steady-state, and single phase. The effect of the permeability of porous media, inlet mass flow rate from porous media, perforations length, and diameter of perforations are studied, for two cases of the phase angles. The results of this study show that, the pressure drop decreases with increasing permeability pf porous media, so the productivity index increasing. Also, increase of inlet mass flow rate from porous media causing an increase in the pressure drop. The perforations length has a few effects on the pressure drop and productivity index, while the diameter of perforations has a greater effect on the pressure drop.