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The present analysis investigates non-Darcy forced convective heat transfer in a cylindrical pipe filled with spherical beads saturated with non-Newtonian drag reducing fluid. The cylindrical pipe is subjected to either a uniform heat flux (UHF) or a constant wall temperature (CWT). In modeling the flow, both the energy equation and a modified momentum (Darcy-Forschheimer-Brinkman) equation are used , in which the variable porosity, flow inertia, Brinkman viscous friction (non-Darcian effects) besides the elongational viscosity of drag reducing fluids are taken into consideration and the finite difference technique is used. The results are obtained for a non-Newtonian drag parameter range of 0≤up≤5000, and nondimensional pressure gradient B up to 108. The results show that the non-Newtonian character of drag reducing fluids have a significant influence on the entrance length, beat transfer characteristics and the temperature profiles. Important results documenting and analyzing the behavior of the entrance length and the heat characteristics and its dependence on the non-Newtonian drag parameter are also reported. To examine the adequacy of the present heat transfer model. The governing equations were solved under conditions corresponding to those in Poulikakos and Renken [20]. The comparison of the calculated Nuf with that of Poulikakos and Renken[20]for d=3 and 5mm,up=0.0.05≤D≤0.15 and 104≤B≤106 shows good agreement and validates the presented heat transfer model.

In this work, the impact of the substrate annealing temperature on the thickness and roughness of La2Ti2O7 thin films was verified. A group of LTO Thin films was grown on Si (100) substrates successfully via pulsed laser deposition technique (PLD) at various annealing temperatures with a constant numbers of pulses and energy per pulse. Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) were used to investigate the thickness and roughness of the deposited La2Ti2O7 thin films. The average thickness of the thin films was decreased due to the increasing in the annealing temperature linearly; the maximum thickness was found (231 nm) when LTO thin film deposited at 500°C. The root mean square roughness was increased linearly with increasing the substrate Temperatures. The minimum roughness was found (0.254 nm) when LTO deposited at (500°C). From the obtained results, its clear evidence that the annealing temperature has an influence on the thickness and roughness of the LTO thin films.

In this work the photodegradation of Rhodamine 6G was studied by adding different amounts of semiconductor (TiO2), as a photocatalyst, to fixed concentration of Rhodamine 6G in water and the mixture was irradiated by UV light in the range from 270 to 280 nm. The UV light has energy of 750 mJ and spot size of 4 cm 2 and the irradiation was done in different exposure times.The absorption spectra of Rhodamine 6G with different amounts of catalyst, before and after irradiation, were recorded and compared. The results showed that the efficiency of the photodegradation process was increased with increasing the amount of semiconductor (TiO2) and irradiation time. The percentage of Rhodamine 6G degradation was 16% when 100 mg of TiO2 was added and irradiated for 10 min, while 82% of Rhodamine 6G was removed when 600mg of TiO2 was added and irradiated for 30 min.This study concluded that the degradation of Rhodamine 6G is increased with increasing the amount of semiconductor (TiO2) and with increasing the irradiation time.

Lanthanum titanium oxide thin films are sometimes used in high-temperature environments. Therefore, it is worth paying attention to the thermal stability of the La2Ti2O7 films. La2Ti2O7 target was made through traditional solid-state reaction way to study the effect of substrate temperature on the characteristics of LTO thin films; A Set of lanthanum titanium oxide thin films has been deposited on to Si (100) substrate through Pulsed laser deposition at different annealing temperatures. The results of X-ray diffraction indicated that the prepared LTO thin films at temperatures up to 700°C are amorphous, while the profilometer Dektak-XT conducted to determine the thickness and roughness of La2Ti2O7 films. The obtained result pointed that the thin film thickness decreased by increasing annealing temperature linearly, and the roughness was inversely proportioning to the increasing of substrate temperature. The value of the lowest roughness equal to 12.28 nm for the thinner film with a thickness of 253.46 nm, while the highest roughness was found to be 14.74 nm for the thicker film at 323.05 nm, which were deposited at 700°C and 500°C respectively, therefore it has been remarked that the annealing temperature influenced the morphology, thickness, and roughness of the LTO thin film.