Abstract Background: The daily usage of maxillofacial prostheses causes them to mechanically deteriorate with time. This study was aimed to evaluate the reinforcement of VST50F maxillofacial silicone by using yttrium oxide (Y2O3) nanoparticles (NPs) to resist aging and mechanical deterioration. Materials and Method: Y2O3 NPs (30–45nm) were loaded into VST50F maxillofacial silicone in two weight percentages (1 and 1.5 wt%), which were predetermined in a pilot study as the best rates for improving tear strength with minimum increase in hardness values. A total of 120 specimens were prepared and divided into the control and experimental groups (with 1 and 1.5 wt% Y2O3 addition). Each group included 40 specimens, 10 specimens for each paramet

The turning process has various factors, which affecting machinability and should be investigated. These are surface roughness, tool life, power consumption, cutting temperature, machining force components, tool wear, and chip thickness ratio. These factors made the process nonlinear and complicated. This work aims to build neural network models to correlate the cutting parameters, namely cutting speed, depth of cut and feed rate, to the machining force and chip thickness ratio. The turning process was performed on high strength aluminum alloy 7075-T6. Three radial basis neural networks are constructed for cutting force, passive force, and feed force. In addition, a radial basis network is constructed to model the chip thickness ratio. T

In this research the effect of cooling rate and mold type on mechanical properties of the eutectic
and hypoeutectic (Al-Si) alloys has been studied. The alloys used in this research work were (Al- 12.6%Si
alloy) and (Al- 7%Si alloy).The two alloys have been melted and poured in two types of molds with
different cooling rates. One of them was a sand mold and the other was metal mold. Mechanical tests
(hardness, tensile test and impact test) were carried out on the specimens. Also the metallographic
examination was performed.
It has been found that the values of hardness for the alloys(Al-12.6%Si and Al-7%Si) which poured in
metal mold is greater than the values of hardness for the same alloy when it poured in a heated

In this work, pure and copper mixed oxide PAni nanofiber thin films are successfully synthesized on silicon substrates by hydrothermal method and spin coating technique at room temperature with thickness of about 325 nm. The structural, surface morphological, optical and photoconductivity properties have been investigated. The XRD results showed that PAni films have crystalline nature, CuO and PAni/CuO nanostructure composites are monoclinic polycrystalline structure. The FESEM images of PAni clearly indicate that it has nanofiber-like structure, whereas the CuO film has spongelike shape. The surface morphology analysis of PAni/CuO composite shows that nanofiber caped with inorganic material which is CuO is a core-shell structure. Op

This research studies the effect of adding five different percentages of polymer (2, 4, 6, 8, and 10% of cement weight) on cement mortar's fresh and hardened properties, which was cured at laboratory temperature for 7, 14, and 28 days. Workability increases with increasing polymer. The workability value was lowest (25.6 and 29.4) % in mixtures containing 2% and 4% of (SBR). Increasing polymer ratios significantly decreased mechanical properties (compressive and flexural strength). Therefore, the best results were at 2% SBR and 4% SBR at 28 days of age. An inverse relationship was recorded between the increase in SBR ratios and polymer-modified cement mortar's compressive and flexural strength values. In general, the high

The photonconductor detectors CdSe:Cu was fabricated as a thin film of (1 μm) in thickness using vacuum evaporation technique. doping with copper was made using vacuum annealing at 350oC under argon atmosphere . The spectral responsivity and spectral detectivity of the detector were determined as a function of incident wavelength on the sample. A remarkable improvement in performance was absorbed for the specimen, which doping with (1-5 wt%) Cu.
The spectral response increases with increasing of wavelength for incident radiation to maximum value, after that , it reduced sharply . There is a shifting for peak responsivity indirect of higher wavelength. The detectivity was increased with doping but its decreased as the concentration in