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In the current research, silver nanoparticles (AgNPs) were mixed with a polymer blend to enhance their optical and electrical properties and antibacterial efficiency. A novel approach via introducing AgNPs into the polymer blend could improve the physical and antibacterial characteristics of the nanocomposites (NCs). In the loading process, two different amounts of AgNPs were respectively encapsulated with polyvinyl alcohol (PVA), polyacrylamide (PAAm) and polyethylene oxide (PEO) polymeric blend via casting method. The prepared films were characterized by X-ray, optical microscope (OM), scanning electron microscopy (SEM), Fourier transformation infrared (FTIR) and UV/Visible. The OM and SEM images showed that the AgNPs were well diffused inside the polymer blend with some weak aggregations. The optical properties were enhanced after doping. The NCs films absorbed UV-ray at (λ=220 nm). The indirect energy gap decreased after loading from 3.80 to 3.10 eV but the direct energy gap decreased from 4.25 to 3.75 eV. The AC electrical properties were studied in the frequency range between 100 Hz to 5 MHz. The dielectric constant and loss of NC films were decreased with the increase of AgNPs, while the electrical conductivity increased. The inhibition zone diameters of Escherichia coli bacteria increased with the increasing of AgNPs contents.

In this research, investigated characterization of pure and Cobalt doped Tin dioxide SnO2: Co with 3, 5 and 7wt% fabricated using radio frequency magnetron sputtering method deposited on glass surfaces. The results showed that prepared SnO2: Co were nano films and poly crystalline in form with favored reflection permanently (110) plan, and the crystallite size decreases as the Co concentration increased 9-14 nm. The optical properties represented by the transmittance of perspicuous and cobalt transplantation SnO2 layers were studied and results showed that highest transmittance obtained was 91% in the pure films and decreased to 78% as the Co concentration increased; the wavelength range was 300-900 nm due to be the increasing of the Co amount during the deposition, leading to a linear increase in mobility and carrier concentration, until a threshold of Co content was overcome and from that point onward the mobility began to decrease. Optical energy gaps of perspicuous and Co transplantation SnO2 nano layers were determined and the energy gap was reduced from 3.50 eV of perspicuous nano layers to 3.29 eV for the highest transplantation concentration.

The importance of this research is to study the effect of changing the temperature at the same time on each of the prepared samples and during the gas sensing processes, the effects of substrate temperature Ts were investigated after precipitation by the microstructural and optical characteristics of cadmium sulfide using thermal spraying method with different temperatures of (300, 400, and 500) ℃. The structural investigations of these films were studied, showing that the increases in substrate temperature were shown cubic and hexagonal phases according to ICDD card no. (21-0929) and (43-0989). The dramatic change occurred at 500 ℃ in changing the phase from hexagonal to a cubic structure. XRD exhibits a dominant plane at (200) for different substrate temperatures. Optical transmittance, absorption coefficient, and energy gap values were calculated by UV/VIS spectrophotometer. These results showed that the band gap values decreased with increasing substrate temperature. The gas sensitivity was tested for NO2 gas at several working temperatures from 175 ℃ to 250 ℃, and various gas concentrations from 150 ppm to 200 ppm and found that the sensitivity increase with increasing both the operating temperature and gas concentration for a Ts at 500 ℃ which offer also the best crystallization the best sensitivity at an operating temperature of 175 ℃ is 75% at a gas concentration of 150 ppm.

The effect of manganese doped cobalt oxide (Co3O4:Mn) was investigated by two different ratios (1% and 3%), which were precipitated by spray pyrolysis technique (SPT), and was adopted using a laboratory designed glass atomizer. Glass substrates were used to deposit films on them, heated at a temperature of 420 ℃. The structural properties were studied through X-ray diffraction. The results showed that all deposit nanostructured films were polycrystalline and there was a decrease in the preferred reflection intensity along (311) plane resulting in a decrease in the crystallite size. Surface properties were analyzed through atomic force microscopy (AFM), which showed a decrease in the roughness and the particle size growth was a vertical columnar rod. The optical characterization displayed that the transmittance of pure Co3O4 nanostructured films was 48% and decreased to 35% for 1% of the Mn concentration, and continued to decrease to 33% with the increase of manganese concentration up to 3%. Optical energy bandgap of pure Co3O4 nanostructured films was 1.435 eV and decreased to 1.419 eV for 1% of Mn concentration, and continued to decrease to 1.367 eV with the increase of Mn concentration up to 3%. The highest percentage sensitivity was for the sample doped with 3% Mn, which was about 65%, for NO2 gas concentration of 600 ppm, at an operating temperature of 200 ℃.

Tin oxide was prepared by chemical methods and then doped with different weight ratios of vanadium 2wt% and 4wt%. The structural, morphological, and optical properties were studied. It was found that all the recorded films had a polycrystalline diffraction pattern and that the predominant reflection was (111) plane. The doping processes resulted in the improvement of crystalline structure and the disappearance of a number of secondary reflections and the direction of the film in a single crystalline pattern, thus reducing the values of energy gap and percentage transmittance. The morphological properties were studied by converting the three-dimensional images into graphic drawings to enable us to easily calculate surface parameters.

We found a new value of supermassive black hole (SMBH) mass in the middle of type 1 Seyfert, NGC 4151 galaxy. In this Study, the image of NGC 4151 galaxy was deprojected to face-on, using spiral galaxy of face-on, and applied IRAF to calculate the ellipticity and position angle of major-axis. A two-dimensional (2D) Fast Fourier Transform (FFT) applied to the deprojected image to calculate the spiral arm of NGC 4151 galaxy, and, in that way, find a central mass AGN 4151 galaxy. We compared our results of the mass of SMBH in in the center of NGC 4151 galaxy with the mass of SMBH calculated using different methods ((direct method: stellar dynamics, gas dynamics, reverberation mapping), and indirect method: MBH-σ*, MBH-Vrot, MBH-n, MBH-Lbulge, and MBH-P correlations). We concluded that the results of mass for these methods are in agreement with the estimated ones, i.e. using direct methods.