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Thin films of Fluorine (F) doped Titanium dioxide (F: TiO2) are deposited at (0, 2 and 4%) Fluorine content by the spray pyrolysis technique (SPT). Structural properties were analyzed by XRD, the results revealed anatase phase for all samples with special orientation along (101) plane. The crystallite size was increased from 9. 75 for pure TiO2 to 10. 67 for (TiO2: 4% F) film, whereas the dislocation density (δ) parameter increased from 109. 18 to 88. 16, but the strain(%) parameter decreases from 36. 21 to 32. 53. Transmittance displays excellent transparent films, in the visible area 83% and 75 %, for TiO2 and 4% F content. The absorption coefficient increased with increasing of F content, AFM images shows that the Undoped TiO2 and TiO2:F films a smooth surface topography with a decrement in The average particle size is noticed to be 77. 16 nm to 55. 36 nm, and average roughness (Ra) of surface was about (5. 45 – 2. 53) nm, and root-mean square (rms) roughness values from 6. 60 nm to 4. 10 nm for the deposited films. However, the optical band gap was slightly decreased from 3. 50 eV to 3. 46 eV with the F content increases. [ABSTRACT FROM AUTHOR]

Thin films of Undoped SnS and SnS: 1% and 3% Ni were fabricated via chemical spray pyrolysis CSP on glass substrates. The as-deposited films were examined by X-ray diffraction, AFM and UV-visible Spectrophotometer. The structural parameters; crystallite size (D), strain and dislocation density were calculated from x-ray diffraction pattern. The prepared films revealed only the SnS phase with a predominant (111) preferred direction. Studies showed that the (D) increased from 11. 23 nm to 12. 41 nm with increase of Ni content, while the strain decreases from 30. 85 to 27. 92. AFM images show that the particle size of the prepared films was in the domain of 74. 79 to 53. 36 nm with increase doping from 1% and 3% Ni, the average surface roughness values were decreases from 7. 70 to 2. 53 nm. and RMS values show decreases from 6. 82 to 3. 26 nm with Ni doping, the transmittance of all films increased as the wavelength increase, and a general decrease in the transmittance is observed as the doping from 0%. 1% and 3% Ni increase. The energy gap Eg was decreased from 1. 38 to 1. 24 eV when Ni doping increase. The effects of Ni doping on absorption coefficient, refractive index and extinction coefficient. It was found that all these parameters increase as the Ni doping increased to 3%. [ABSTRACT FROM AUTHOR]

NiO and NiO: Al films were fabricated employing chemical spray pyrolysis (CSP) technique. XRD indicate a polycrystalline structure and dominant direction at (012), the grain size raised from 11. 55 nm to 13. 14 nm as (Al) content increment, whereas the dislocation density (δ) parameter decreases from 74. 96 to 57. 25, while the strain (%) decreases from 30. 01 to 26. 37. The AFM images show that the particle size (Tp) of the deposited films was in the domain of (70. 03 to 42. 54 nm) with increase doping from 1% Vol to 3% Vol. Al, average surface roughness Ra values was decreases from 6. 88-2. 22 nm. and RMS values show decreases from (7. 74 to 3. 22) nm with Aluminum doping. The transmittance spectra were recorded to calculate the optical properties using computer program. Transmittance more than 80 % was observed for all films in visible region. The energy gap Eg was decreased from (3. 39 to 3. 29) eV when Al doping increase. The Aluminum doping was enhanced the optical parameters by increasing these values. [ABSTRACT FROM AUTHOR]

Bismuth ferrite (BiFeO3) was synthesized by the sol-gel method and the structural properties have been examined via the use of XRD technique. Crystallite size estimated through the use of Scherrer equation for samples calcined at a temperature of 300°C and 400°C for two hours respectively, which clarify the increase in crystallite size as the temperature increases and also XRD indicated the fact that in addition to the formation regarding single phase BiFeO3 an impurity phase has been identified. Diagnosing the samples, showed that BiFeO3 has rhombohedral structure. AFM test for samples calcined at (300 and 400°C) proved that the particle size is in nanoscale and the grain size of bismuth ferrite increases with the increase in temperature. [ABSTRACT FROM AUTHOR]

Films of Undoped SnS and SnS:Cr have been prepared by using CSP method. From XRD patterns it is found that the prepared films are hexagonal wurtzite with a predominant peak (101) and the crystallite size is about (13. 28-15. 23) nm with Cr doping, whereas the strain decrease from 2. 58 to 2. 27 with Cr doping. AFM images show the Undoped SnS and SnS:Cr surface morphology. The average diameter was in the area of (82. 64), (67. 8) and (49. 75) nm for the (SnS, SnS:2% Cr and SnS:4% Cr) respectively. The surface roughness and rms values of the deposited films were (4. 78, 4. 18 and 1. 25) nm and (5. 83, 4. 06 and 2. 20) nm for SnS, SnS:2% Cr and SnS:4% Cr respectively. The transmittance of the film was observed to decrease for Cr doping, The decreasing in the optical energy gap which was found according to Tauc model were (1,48-1,37) eV, Results illustrate that both absorption coefficient and extinction coefficient of the films are increasing with increasing with Cr content in SnS thin films. The refractive index was found to decreased from 3,5-3,3 as the doping percentage increase. [ABSTRACT FROM AUTHOR]

Chemical spray pyrolysis (CSP) was used to prepare pure Titanium dioxide and TiO2:Zn thin films. The base temperature of the prepared films was held at 450°C during deposition. The as-deposited thin films had a polycrystalline structure with a strong peak along the (121) plane, according to XRD data. Furthermore, Using an Atomic Force Microscope, the surface topography of thin films was examined (AFM). The AFM images depicted the average particle size nanostructures. In the visible field, the transmittance of pure TiO2 was found to be about 70%. The band gap for pure TiO2:Zn is reduced with the increase of doping. [ABSTRACT FROM AUTHOR]

Cobalt ferrite Co1.2Fe1.8O4 nanoparticles were synthesized using the sol-gel auto combustion process. The impact of calcination temperature on structural, Magnetic and electrical properties has been investigated. The cubic spinel phase formation of ferrite structure was confirmed using Fourier Transform-Infrared Spectroscopy (FT-IR) and X-ray Diffraction Patterns (XRD). The size of the formed crystallite of ferrite samples ranges from 26.909 to 39.712 nm and was discovered to be dependent on the calcination temperature. According to the images obtained with a Field Emission-Scanning Electron Microscopy (FE-SEM), the particle size increases as the calcination temperature rises. The existence of Co, Fe, and O in all samples was also verified using Energy Dispersive Spectrum (EDS). Magnetic parameters for the as-burnt and calcined samples such as coercivity, saturation magnetization, and remanence field were investigated using a Vibrating Sample Magnetometer (VSM). All of the samples exhibited ferrimagnetic behavior. Saturation magnetization (Ms),remanance magnetization (Mr), and squareness ratio (Mr / Ms) increase as the calcination temperature increase. This behavior is linked to spin canting and disturbance in the surface spin. Using an LCR meter, dielectric loss factor (ε''), dielectric loss angle (tanδ), the dielectric constant (ε'), and σac conductivity of all samples were investigated at room temperature as a function of frequency. Based on Koop's theory, Maxwell-Wagner polarization process, and hopping of electrons, the differences have been described in dielectric properties at frequencies ranging from 50Hz to 2MHz. With increasing frequency, all-dielectric properties exhibited natural behavior. [ABSTRACT FROM AUTHOR]

Pure ZnS and Co-doped ZnS thin films were grown using Chemical Spray Pyrolysis (CSP)Technique, and the concentration of the Co doping level (1% and 3%). The hexagonal crystal structure was present in all of the films as shown by X-ray diffraction (XRD) structure of all films. Atomic Force Microscopy (AFM) revealed that film surface was homogeneous. Optical properties of undoped ZnS and the optical bandgap energy (Eg) of Co doped indicated a reduction with Co doping level (1% and 3%). The root of ferromagnetic order at low temperatures (5 K and 100 K) could be traced back to point defects like, zinc interstitials, sulfide vacancies, and zinc vacancies as well as the grain-boundary impact. [ABSTRACT FROM AUTHOR]

This revision aims is to examine the electrical possessions of AC composite materials Polyvinyl alcohol-Polyacrylamide-Silver (PVA-PAAm-Ag) and Polyvinyl alcohol-Polyacrylamide-Polymethyl methacrylate-Silver (PVA-PAAm-PMMA-Ag) at different frequencies between 100 Hz – 6 MHz and the Ag additives. PVA-PAAm-Ag and PVA-PAAm-PMMA-Ag were prepared using the solution casting method. The film thickness was measured using an electrical micrometer to be 80 µm. The LC meter is used for the AC electrical properties. The results show that the dielectric constant (ɛ) and dielectric loss (δ) decrease with the increasing frequency, and δ increased with the increasing content of Ag. Electrical conductivity (σ) augmented with the rising frequency and Ag content in PVA-PAAM-Ag and PVA-PAAM-PMMA-Ag composite. [ABSTRACT FROM AUTHOR]

Undoped and Antimony (Sb)-doped CdO at (1 and 3) wt. % were sprayed on glass substrate at 450°. X-ray diffraction analysis disclosed a rhombohedral crystalline phase for prepared CdO films. The crystallite size was varied from (12. 74 – 14. 47) nm with Sb accompanied with a decrease of strain parameter from 27. 20 to 23. 94, Morphological properties were evaluated via AFM which assure the increase in crystallite size with Sb content. Furthermore, the spectral transmission decrease from 90-85% and the optical energy band gap decrease from 2. 72-2. 62 eV, also this study extended to evaluate the optical constants via photon energy and wavelength. [ABSTRACT FROM AUTHOR]

In this paper, Minkowski fractal split ring resonator is proposed. Left handed behavior is obtained of Minkowski model for two iterations above classical model (square). Left handed, also called metamaterial has new applications in the field of electrodynamics. Permeability, permittivity, and refractive index are calculated to prove its behavior. Negative value of refractive index at resonant frequencies confirms left handed behavior of this model. Fractal shape of the unit cell gave it the advantage of size reduction. Reducing size of this model reach to 48% of its physical area. Promising results can get by inserting this kind of materials in communication systems. [ABSTRACT FROM AUTHOR]

Thin films of ZnO and (ZnO: Mn) are grown via chemical spray pyrolysis (CSP) technique Structure analysis of ZnO and ZnO: Mn films were studied via XRD. The results offer that films were cubic with a prevailing peak along (002). The grain size is (10. 45-12. 41) nm, whilst the strain decrease from 31. 68 to 27. 91 with Mn. AFM images assure the creation of nanostructured. It was found that the Average Particle size, average roughness (Ra) and root mean square rough (Rrms) decreased with an increase of Mn content in ZnO films, Films are transparent in visible area with cut-off wavelength at 370 nm. High transparency is seen at (>85%) in the visible area. Optical bandgap energy decreases from 3. 05 to 2. 95 eV with increase of Mn doping content. [ABSTRACT FROM AUTHOR]

Spherical gold nanoparticles (AuNPs) chemically synthesized by Turkevich method, it coated with sodium silicate stock solution (Na2SiO3). Study different rate effect (SiO2 and ethanol) on position of surface plasmon resonance (SPR) of gold nanoparticles (AuNPs) after coated by using UV–Vis absorption spectroscopy. UV–vis spectrum showed that rate (SiO2 and ethanol) had effect in the coated gold nanoparticles (AuNPs), that Peak band gold nanoparticles (AuNPs) uncoated at (515nm) and this peak was shifted to longer wavelength (518nm) after coating. Coated after get a little shift in position of surface plasmon resonance (SPR) this means that coated method has an important role in maintain on gold nanoparticles (AuNPs) stability. [ABSTRACT FROM AUTHOR]