Blends of Polymethyl methacrylate (PMMA)/polyvinyl alcohol (PVA) doped with 2% weight percentage of Sn were prepared with different blend ratios using casting technique. The measurements of A.C conductivity σa.c within the frequency range (25kHz – 5MHz) of undoped and Sn doped PMMA/PVA blends obeyed the relationship σ= Aws were the value of s within the range 0 > s > 1. The results showed that σa.c increases with the increase of frequency. The exponent s showed preceding increase with the increase of PVA content for PMMA/PVA blends doped with Sn. The dielectric constant, dielectric loss, A.C electrical conductivity are varied with the concentration of PVA in the blend and frequency of applied electrical field.
In this research thin films of (CdTe) have been prepared as pure and doped by Zn
with different ratios (1,2,3,4,5)% at thickness (400+25)nm with deposition rate (2±0.1)nm,
deposited on glass substrate at R.T. by using thermal evaporation in vacuum . All samples
were annealed at temperature (523,573,623,673)K at 1h.
The structural prop erties of all prepared thin films, doped and undoped have been
studied by using XRD. The analysis reveals that the structures of the films were
polycrystalline and typed cubic with a preferred orientation along (111) plane for the
undoped films with (2,3)% of zinc , and shifting (2ÆŸ) for doped films . The annealing films
at temperature 573 K and Zn:3% show decreasing in
Zinc Oxide (ZnO) thin films of different thickness were prepared
on ultrasonically cleaned corning glass substrate, by pulsed laser
deposition technique (PLD) at room temperature. Since most
application of ZnO thin film are certainly related to its optical
properties, so the optical properties of ZnO thin film in the
wavelength range (300-1100) nm were studied, it was observed that
all ZnO films have high transmittance (˃ 80 %) in the wavelength
region (400-1100) nm and it increase as the film thickness increase,
using the optical transmittance to calculate optical energy gap (Eg
opt)
show that (Eg
opt) of a direct allowed transition and its value nearly
constant (~ 3.2 eV) for all film thickness (150
In this paper the effect of nonthermal atmospheric argon plasma on the optical properties of the cadmium oxide CdO thin films prepared by chemical spray pyrolysis was studied. The prepared films were exposed to different time intervals (0, 5, 10, 15, 20) min. For every sample, the transmittance, Absorbance, absorption coefficient, energy gap, extinction coefficient and dielectric constant were studied. It is found that the transmittance and the energy gap increased with exposure time, and absorption. Absorption coefficient, extinction coefficient, dielectric constant decreased with time of exposure to the argon plasma
Glass Ionomer Cement (GIC) is one of the important dental temporary filing materials. The aim of this study is to evaluate the effect of adding 3, 5 and 7 wt. % of TiO2 microparticles to conventional GIC powder (Riva Self Cure) on mechanical properties and its effect on absorption and solubility processes. TiO2 particles additives improved compressive strength and biaxial flexural strength, where the compressive strength increased with increasing in the added ratio, while the highest value of the biaxial flexural strength was at 3 wt.%. The addition of TiO2 particles improved the surface Vickers microhardness values, with highest value at 5 wt. %. On other hand TiO2 addition im
... Show MoreIn this work, lead oxide (PbO) thin films were deposited using D.C. sputtering method on a surface of glass substrates and then thermally annealed at a temperature of 473K with annealing times of (1,2 and 3) hours. The structural, morphological, and optical properties of films were determined using X-ray diffraction (XRD), atomic force microscopy (AFM), FT-IR, and UV-Visible spectroscopy. The structure studies confirmed that PbO films are polycrystalline structures in an orthorhombic phase with average grain size (24.51, 29.64, 46.49, 16) nm with increasing annealing time. From AFM, the roughness of the film surface (3.26, 1.76, 1.61, 1.79) nm as the film annealing time increases. The optical band gap values of the PbO thin fi
... Show MoreThe physical and elastic characteristics of rocks determine rock strengths in general. Rock strength is frequently assessed using porosity well logs such as neutron and sonic logs. The essential criteria for estimating rock mechanic parameters in petroleum engineering research are uniaxial compressive strength and elastic modulus. Indirect estimation using well-log data is necessary to measure these variables. This study attempts to create a single regression model that can accurately forecast rock mechanic characteristics for the Harth Carbonate Formation in the Fauqi oil field. According to the findings of this study, petrophysical parameters are reliable indexes for determining rock mechanical properties having good performance p
... Show MoreIn this paper, Zinc oxide were deposited on a glass substrate at room temperature (RT) and two annealing temperatures 350ºC and 500ºC using laser induced plasma technique. ZnO nanofilms of 200nm thickness have been deposited on glass substrate. X-RAY diffraction (XRD), atomic force microscopy and UV-visible spectrophotometer were used to analyze the results. XRD forms of ZnO nanostructure display hexagonal structure with three recognized peaks (100), (002), and (101) orientations at 500ºC annealing temperature. The optical properties of ZnO nanostructure were determined spectra. The energy gap was 3.1 eV at 300 oC and 3.25eV at 500ºC annealing temperature.
Changes in mechanical properties of material as a result of service in different conditions can be provided by mechanical testing to assist the estimation of current internal situation of these materials, or the degree of deterioration may exist in furnaces serviced at high temperature and exceed their design life. Because of the rarity works on austenitic stainless steel material type AISI 321H, in this work, ultimate tensile strength, yield strength, elongation, hardness, and absorbed energy by impact are evaluated based on experimental data obtained from mechanical testing. Samples of tubes are extracted from furnace belong to hydrotreaterunit, also samples from un-used tube material are used to make comparisons between these properti
... Show MoreBackground: Polymethyl methacrylate (PMMA) is the most commonly used material in denture fabrication. The material is far from ideal in fulfilling the mechanical requirement. The purpose of this study was to evaluate the effect of addition of 3% wt of treated (silanized) Titanium oxide Nano filler on some physical and mechanical properties of heat cured acrylic denture base material. Materials and methods: 100 specimens were constructed, 50 specimens were prepared from heat cure PMMA without additives (control) and 50 specimens were prepared from heat cure PMMA with the addition of TiO2 Nano fillers. Each group was divided into 5 sub groups according to the test performed which was mixed by probe ultra-sonication machine. Results: A highly
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