In this research, we studied the structural properties of SnO2 films nanostructure which prepared by chemical spray pyrolysis method at room temperature on the rules of glass heated (400oC) with rate of spraying (2.5 ml/ min). The effect of annealing temperaturs (450,500,550,600 and 650oC) for two hours on those properties has been indicated. The results of x-ray diffraction showed that all of the prepared films were polycrystalline with tetragonal type and orientation was (110) for all models before and after annealing, and the annealing led to an increase in the grain size. The full width at half maximum (FWHM) values of the (110) peaks of the films decreased from 1.492o to 1.064o with increasing annealing temperature .The surface morphology of the (SnO2) nanostructure films have been studied using atomic force microscopy (AFM) which indicated that the grown films showed good crystalline and homogeneous surface . The Root Mean Square (RMS) values and surface roughness of the films decreased with increasing the annealing temperature. The optical properties of the films were studied by (UV-VIS-NIR) spectrophotometer in the wavelength range (300-1100 nm). The optical transmission results showed high transmittance (87%) at annealing a temperature (650oC). The energy gap for direct transmission was calculated before and after annealing. From the gas sensing measurements of SnO2 films for (CO2 , NH3), showed a good sensitivity at 50oC. It was found the that best sensitivity of SnO2 films at annealing temperature 650oC were (100%) for NH3 (98.78%).
Preparation of epoxy/ TiO2 and epoxy/ Al2O3 nanocomposites is studed and investigated in this paper. The nano composites are processed by different nano fillers concentrations (0, 0.01, 0.02 ,0.03, 0.04 ,0.05 ,0.07 and 0.1 wt%). The particles sized of TiO2,Al2O3 are about 20–50 nm.Epoxy resin and nano composites containing different shape nano fillers of (TiO2:Al2O3 composites),are shear mixing with ratio 1 to 1,with different nano hybrid fillers concentrations( 0.025 ,0.0 5 ,0.15 ,0.2, and 0.25 wt%) to Preparation of epoxy/ TiO2- Al2O3 hybrid composites. The mechanical properties of nanocomposites such as bending ,wearing, and fatigue are investigated as mechanical properties.
In this paper, we study the effects of coherent and incoherent illumination on the optical imaging system. The effects were studied qualitatively in terms of Point Spread Function (PSF) and Modulation Transfer Function (MTF), and quantitatively in terms of Root Mean Square Error (RMSE). Different values of radius of aperture were investigated in the presence and absence of spherical aberration with various magnitudes of spherical aberration (M=1, 2, and 3). The experiments were performed using homogeneous media.
The results show that imaging with incoherent illumination is better than imaging with coherent illumination, especially for small aperture. Also, we found that the effects of spherical aberration
... Show MoreSlurry-infiltrated fibrous concrete (SIFCON) is a special type of concrete that has great strength, as well as high ductility. However, the unit weight is high, which exceeds the unit weight of fiber-reinforced concrete, because of the high fiber content. This research aims to verify the compressive and flexural strength, as well as the density of SIFCON when using two different fibers (steel and polyolefin). Sometimes mono type of fiber steel or polyolefin, sometimes by hybridizing two types of fiber steel + polyplefin. Volume fraction (6% for all species) was used. Hook-end steel fiber and polyolefin fiber are used. With hybridization, a total volume fraction of 6% was used, which
This study included preparation for the unsaturated polyester samples before and after reinforced by the Alumina oxide powder of different volume fraction amounting (2%,4%,6%). And this research included the study of some of mechanical properties such as (Hardness,compressive,wear). The results showed that the increase of the hardness and compressive strength after the reinforced and the increase with the volume fraction increase. As the wear test shows that the wear rate increases with applied load increase(5,10,15) from (10.6-18.6) gm/cm befor reninforced and from(5.4-15.2)gm/cm,(4.7-12.9)gm/cm,(48.1)gm/cm,after reinforced from the different volume fraction, and t
... Show MoreThis study exposed to use the liquid whey (which was produced from of soft cheese processed) partially or completely instead of milk in fatty cake, this whey residue is still not used, instead it is thrown in rivers which effect different environment and economic problems. Different concentrations was used (25% , 50% , 75% , and 100%) of whey in baked cake , Volume , height and other different properties ( panel taste ) was studied too . Sensory evaluation results showed that an improved in all the character of the baked cake was happen by the used of 25% and 50% of the whey in comparison with the control treatment, the 75% replacement showed a decrease in appearance , texture and tenderness , while the degrees of color and fla
... Show MoreIncremental sheet metal forming is a modern technique of sheet metal forming in which a uniform sheet is locally deformed during the progressive action of a forming tool. The tool movement is governed by a CNC milling machine. The tool locally deforms by this way the sheet with pure deformation stretching. In SPIF process, the research is concentrate on the development of predict models for estimate the product quality. Using simulated annealing algorithm (SAA), Surface quality in SPIF has been modeled. In the development of this predictive model, spindle speed, feed rate and step depth have been considered as model parameters. Maximum peak height (Rz) and Arithmetic mean surface roughness (Ra) are used as response parameter to assess th
... Show MoreIn the present work, it had been measured the concentration of radon gas (CRn) for (10) samples of cement used in constructions before and after painting them using enamel paint, purchased from the local markets, to see the extent of its ability to reduce emissions of Rn-222 in the air. These samples were obtained from different sources available in the local markets in Baghdad and other provinces. The measurements were done by the American-made detector (RAD7). The results showed that the highest CRn in the air emitted from cement samples after coating was in the cement sample (Iranian origin) where the concentration was (58.27 Bq/m3) while the lowest CRn was found in building material samples
... Show MoreThe specifications of lubricating oil are fundamentally the final product of materials that have been added for producing the desired properties. In this research, spherical nanoparticles copper oxide (CuO) and titanium oxides (TiO2) are added to SAE 15W40 engine oil to study the thermal conductivity, stability, viscosity of nano-lubricants, which are prepared at different concentrations of 0.1%, 0.2%, 0.5%, and 1% by weight, and also their pour point, and flash point as five quality parameters. The obtained results show that CuO nanoparticles in all cases, give the best functionality and effect on engine oil with respect to TiO2. With 0.1 wt. % concentration, the thermal conductivity of CuO/oil and TiO2/
... Show MoreThermal energy storage is an important component in energy units to decrease the gap between energy supply and demand. Free convection and the locations of the tubes carrying the heat-transfer fluid (HTF) have a significant influence on both the energy discharging potential and the buoyancy effect during the solidification mode. In the present study, the impact of the tube position was examined during the discharging process. Liquid-fraction evolution and energy removal rate with thermo-fluid contour profiles were used to examine the performance of the unit. Heat exchanger tubes are proposed with different numbers and positions in the unit for various cases including uniform and non-uniform tubes distribution. The results show that
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