A tungsten inert gas (TIG) welding is one of the most popular kinds of welding used to join metals mainly for aluminum alloys. However, many challenges may be met with this kind of joining process; these challenges arise from decay of mechanical properties of welded materials. In the present study, an attempt was made to enhancing the mechanical properties of TIG weld joint of 6061-T6 aluminum alloy by hardening the surfaces using shoot peening technique. To optimize the shoot peening process three times of exposure (5, 10, and 15) min. was used. All peened and unpeened, and welded and unwelded samples were characterized by metallographic test to indicate the phase transformation and modification in microstructure occurring during welding process. Tensile test and Vickers micro-hardness measurements were performed for all samples to investigate the effect of shoot peening on mechanical properties of welded aluminum.
The results indicated a significant improvement in properties for peened welded and unwelded samples compared with those unpeened one. Also, the results showed that the tensile and microhardness properties were increased with increasing the time of exposure to 15 min. due to generation of compressive residual stresses at surface.
The electrical properties of pure NiO and NiO:Au Films which are
deposited on glass substrate with various dopant concentrations
(1wt.%, 2wt%, 3wt.% and 4wt.%) at room temperature 450 Co
annealing temperature will be presented. The results of the hall effect
showed that all the films were p-type. The Hall mobility decreases
while both carrier concentration and conductivity increases with the
increasing of annealing temperatures and doping percentage, Thus,
indicating the behavior of semiconductor, and also the D.C
conductivity from which the activation energy decrease with the
doping concentration increase and transport mechanism of the charge
carriers can be estimated.
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Copper oxide thin films were synthesized by using spray pyrolysis deposition technique, in the temperature around 400°C in atmosphere from alcoholic solutions. Copper (II) chloride as precursor and glass as a substrate. The textural and structural properties of the films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD). The average particle size determined from the AFM images ranged from 30 to 90 nm and the roughness average was equal to 9.3 nm. The XRD patterns revealed the formation of a polycrystalline hexagonal CuO. The absorption and transmission spectrum, band gap, film thickness was investigated. The films were tested as an |
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Zinc Oxide transparent thin films (ZnO) with different thickness from (220 to 420)nm
±15nm were prepared by thermal evaporation technique onto glass substrates at 200 with
the deposition rate of (10 2) nm sec
-1
, X-ray diffraction patterns confirm the proper phase
formation of the material. The investigation of (XRD) indicates that the (ZnO) film is
polycrystalline type of Hexagonal and the preferred orientation along (002) plane. The Optical
properties of ZnO were determined through the optical transmission method using ultraviolet-visible spectrophotometer with wavelength (300 – 1100) nm. The optical band gap values of
ZnO thin films were slightly increased from (2.9 - 3.1) eV as the film thickn
This article studied some linear and nonlinear optical characteristics of different pH solutions from anthocyanin dye extract at 180 oC from red cabbage. First, the linear spectral characteristics, including absorption and transmittance in the range 400-800 nm for anthocyanin solution 5% v/v with different pHs, were achieved utilizing a UV/VIS spectrophotometer. The experimental results reveal a shift in the absorption toward the longer wavelength direction as pH values increment. Then, the nonlinear features were measured using the Z-scan technique with a CW 532 nm laser to measure the nonlinear absorption coefficient through an open aperture. A close aperture (diameter 2 mm) calculates the nonlinear refractive index. The open Z-scan sh
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In this work, pure and Ag-doped nickel oxide (NiO) thin films were deposited on glass substrates with different dopant concentrations (0.1, 0.2, 0.3 and 0.4 wt.%) by pulsed-laser deposition (PLD) technique at room temperature. These films were annealed at temperature of 450 °C. The structural and optical properties of the prepared thin films were studied. It was found that annealing process has lead to increase the transmittance of the deposited films. Also, the transmittance was found to increase with doping concentration of silver in the deposited NiO films. The optical energy gap was decreased from 3.5 to 3.2 eV as the doping concentration was increased to 0.4 %.
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In this study, an improved process was proposed for the synthesis of structure-controlled Cu2O nanoparticles, using a simplified wet chemical method at room temperature. A chemical solution route was established to synthesize Cu2O crystals with various sizes and morphologies. The structure, morphology, and optical properties of Cu2O nanoparticles were analyzed by X-ray diffraction, SEM (scanning electron microscope), and UV-Vis spectroscopy. By adjusting the aqueous mixture solutions of NaOH and NH2OH•HCl, the synthesis of Cu2O crystals with different morphology and size could be realized. Strangely, it was found that the change in the ratio of de-ionized water and NaOH aqueous solution led to the synthesis of Cu2O crystals of differen
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Abstract
Lack of safe available non-resistant treatment for visceral leishmaniasis (Kala-azar) keeps limiting the complete cure of this disease ,drugs that have toxic side effects or lack of effectiveness have led to disease relapse ,all these factors have lightened the way to the search for imperative drugs from natural resources that have been shown to have antileishmanial activity through literature survey
. In the present study, the comparative in vitro anti-leishmania activity of various fractions of Osteospermum ecklonis aerial parts fractions have been evaluated. Extracts were prepared through maceration and Soxhlet apparatus using 85% meth
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The media, especially the satellite channels in our time, are one of the most important pillars of daily life, public and private, for society and people, and are considered by sociologists and sociologists as one of the most important factors of social upbringing and the most important, as a result of the technological and technological development of the media as well as increasing their numbers and vertical and horizontal expansion locally, As well as entering into the lives of individuals and people and leading them to important sites within their interests and preferences, not to mention the long time spent exposure to those media and benefit from the programs offered or broadcast. , The problem of this research is that there is a l
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Aim: The present study aims to improve the poor water solubility of zaltoprofen which is a non-steroidal anti-inflammatory drug (NSAIDs) with a potent analgesic effect using solid dispersion then formulate it as a hollow type suppository to be more convenient for geriatric patients. Materials and Method: Zaltoprofen solid dispersions were prepared by solvent evaporation technique in different zaltoprofen: Soluplus® ratios. Results: Among the formulations tested, zaltoprofen solid dispersion preparation using 1:5 (zaltoprofen: Soluplus®) ratio showed the highest solubility and selected for further investigation. Solid dispersion characterization was evaluated by differential scanning calorimetry (DSC), X-ray diffraction study (XRD) and Fou
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