In this research, the structural and optical measurements were made on the Zinc oxide (ZnO) films prepared by two methods once by using chemical spray pyrolysis technique, and another by using thermal evaporation technique before and after irradiation by Gamma –Ray (γ – rays) from source type (Cs 137) with an energy (0.611)MeV as a function of gamma dose (0.15,0.3 and 0.45) Gy. The thickness of all films prepared by two method was about (300 ± 50) nm. XRD is used to characterize the structural properties, the results demonstrated that all samples prepared by two method before and after irradiation have polycrystalline structure with a preferred orientation (002).Also it showed that the structural properties are weakly dependent on the gamma dose. The optical measurement shows that all ZnO films prepared by two method have a direct energy gap, and they in general decrease with the increase of Gamma dose while the optical constant such as absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of the dielectric constant and optical conductivity showed an opposite trend, these values increase with the increase of irradiation dose. As well as all optical properties for the samples prepared by thermal evaporation technique is higher than the samples prepared by chemical spray pyrolysis technique.
In this study, generation of elliptical gears with different teeth profiles of crowned involute, double circular arc (DCA), and combined (crowned involute with DCA) has been developed. The resulting mathematical equations have been computerized and feed to CNC end mill machine to manufacture elliptical gear models with different profiles. These models are investigated in plane polariscope to show the resulting stresses under certain load. Comparison of photo-elastic stress results shows that combined elliptical gears with DCA side as a loaded side have a minimum resulting contact stress with a reduction percentage of 40% compare with contact stresses in counterpart elliptical gear of involute profile (which is commonly u
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In this study, epoxy was used as a matrix for composite materials, with E-glass fiber, jute and PVC fiber which was woven roving fiber, as reinforcement with volume fraction (Vf= 30%). There are two of prepared types of epoxy non reinforced, epoxy reinforced with E-glass, jute and PVC fibers including study of mechanical tests (Impact test, Bending test) different temperature and thermal conductivity and calculating the temperatures coefficient at different temperature. Results show that elastic modulus at rate values decrease to the increase of temperature and the impact strength, impact energy and thermal conductivity increase with increase temperature.
The media: ((Providing people with the right news, audio information, and constant facts that help them form a correct opinion in an incident or a problem, this opinion gives an objective expression of the mentality of the audience, their trends and tendencies). The German scientist Autogroot defines it as "the objective expression of the mentality of the audience, their spirit, their tendencies, and their trends at the same time." Whereas for "Aristotle", (Language) is a specific verbal system created as a result of an agreement between the members of the human group somewhere )). It is a symbol of thought, and a difference between humans and animals. Pronunciation and thought for “Aristotle” are intertwined: without pro
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Laboratory experience in Iraq with cold asphalt concrete mixtures is very limited. The design and use of cold mixed asphalt concrete had no technical requirements. In this study, two asphalt concrete mixtures used for the base course were prepared in the laboratory using conventional cold-mixing techniques to test cold asphalt mixture (CAM) against aging and moisture susceptibility. Cold asphalt mixtures specimens have been prepared in the lab with cutback and emulsion binders, different fillers, and curing times. Based on the Marshal test result, the cutback proportion was selected with the filler, also based on the Marshal test emulsion. The first mixture was medium setting cationic emulsion (MSCE) as a binder, hydrate
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Background: Humeral diaphyseal fracture usually
heals with closed methods but when nonunion
develops then it needs surgical intervention in the
form of plating and bone grafting, intramedulary
nailing (open or closed simple or interlocking nails)
and external fixators (circular or one plane fixator).
In our unit we treated non union humeral
diaphyseal fracture with plating and bone grafting
shortening of fracture ends up to 4 to 5cm when
needed. Methods: This study was conducted at
Orthopaedic Department of AL-Sadar General
Hospital from January 2004 till December2005 .
We included 20 cases with atrophic non-union in
12(60%) and hypertrophic non-union in 8 (40%)
patients. All atrophic non-union w
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The regressor-based adaptive control is useful for controlling robotic systems with uncertain parameters but with known structure of robot dynamics. Unmodeled dynamics could lead to instability problems unless modification of control law is used. In addition, exact calculation of regressor for robots with more than 6 degrees of freedom is hard to be calculated, and the task could be more complex for robots. Whereas the adaptive approximation control is a powerful tool for controlling robotic systems with unmodeled dynamics. The local (partitioned) approximation-based adaptive control includes representation of the uncertain matrices and vectors in the robot model as finite combinations of basis functions. Update laws for the weighting matri
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The methods of the Principal Components and Partial Least Squares can be regard very important methods in the regression analysis, whe
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The qualified subjects for this study included 33 patients with benign and malignant oral tumors aged 15-75 years and 31 matched age and gender healthy subjects used as control. Proteins measurements included total protein, albumin, globulines in sera and saliva samples, and immunoglobulins (IgG, IgM, IgA) in sera samples of control and patients. Meanwhile, polyacrylamide gel electrophoresis (PAGE) was used to differentiate between protein patterns in both serum and saliva samples among the studied groups. The gel was also stained for glycoprotein to evaluate as well the changes in glycoprotein contents. For total protein, the results revealed a signifigant increase (P?0.01) in both samples (serum and saliva) of patient group. Albumin conce
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