The optical properties for the components CuIn(SexTe1-x)2 thin films with both values of selenium content (x) [0.4 and 0.6] are studied. The films have been prepared by the vacuum thermal evaporation method with thickness of (250±5nm) on glass substrates. From the transmittance and absorbance spectra within the range of wavelength (400-900)nm, we determined the forbidden optical energy gap (Egopt) and the constant (B). From the studyingthe relation between absorption coefficient (α) photon energy, we determined the tails width inside the energy gap.
The results showed that the optical transition is direct; we also found that the optical energy gap increases with annealing temperature and selenium content (x). However, the width of localized tails states in the gap is found to decrease with increasing both of annealing temperature and selenium content (x). According to Mott-Davis models, we discussed our results by supposing a model for density of states N(E) as a function of energy (E).
Compounds were prepared from In2O3 doped SnO2 with different doping ratio by mixing and sintering at 1000oC. Pulsed Laser Deposition PLD was used to deposit thin films of different doping ratio In2O3: SnO2 (0, 1, 3, 5, 7 and 9 % wt.) on glass and p-type wafer Si(111) substrates at ambient temperature under vacuum of 10-3 bar thickness of ~100nm. X-ray diffraction and atomic force microscopy were used to examine the structural type, grain size and morphology of the prepared thin films. The results show the structures of thin films was also polycrystalline, and the predominate peaks are identical with standard cards ITO. On the other side the prepared thin films declared a reduction of degree of crystallinity with the increase of doping ra
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The gas sensing properties of undoped Co3O4 and doped with Y2O3 nanostructures were investigated. The films were synthesized using the hydrothermal method on a seeded layer. The XRD, SEM analysis and gas sensing properties were investigated for the prepared thin films. XRD analysis showed that all films were polycrystalline, of a cubic structure with crystallite size of (12.6) nm for cobalt oxide and (12.3) nm for the Co3O4:6% Y2O3. The SEM analysis of thin films indicated that all films undoped Co3O4 and doped possessed a nanosphere-like structure.
The sensi
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Background: Poly (methylmethacrylate) is not ideal in every aspect and has disadvantages such as insufficient surface hardness, increase water sorption and poor impact resistance and the latter being the primary cause of fracture of denture base resins. The aim of this study was to evaluate the effect of addition of silanized nano- hydroxyapatite (HA) on some properties of heat cured acrylic denture base material. Materials and methods: HA nano particles were first silanized with ï§MPS (tri methacryloxypropyletrimethoxy silane coupling agent) then ultrasonicated with methylmethacrylate (monomer) to disperse agglomerated nano particles and mixed with polymer. 2% by wt of HA nano particles was selected as the best concentration that add
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Objective This study evaluated the effects of adding titanium oxide (TiO2) nanofillers on the tear strength, tensile strength, elongation percentage, and hardness of room-temperature-vulcanized (RTV) VST50F and high-temperature-vulcanized (HTV) Cosmesil M511 maxillofacial silicone elastomers. Methods Two types of maxillofacial elastomers, VST50F RTV and Cosmesil M511 HTV, were used. Nano-TiO2 powder was applied as a nanofiller. A total of 120 specimens were fabricated, 60 each of VST50F and Cosmesil M511. The specimens of each type of elastomer were divided into three equal groups on which tests were conducted for tear strength, tensile strength, and hardness i.e., 20 specimens were used for each test. Each group of 20 specimens was further
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Premature degradation is the problem of maxillofacial silicones, significantly affected by ultraviolet exposure, contributing to silicones photodegradation. Degradation necessitates frequent replacement of prostheses that increase the total cost of rehabilitation.
This study evaluated the effect of bisoctrizole on the ultraviolet absorption properties of silicone material and the stability of this absorption over time. Also, the bisoctrizole effect on the surface roughness of silicone was evaluated.
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