Powder of silver nanoparticles was prepared by Sol - Gel method successfully using silver nitrate , (AgNO3) gesture is added to sodium citrate (C6H5O7Na3) as a reducing agent and by using Magnetic Stirrer to mix the solutions and heated then using centrifuge machine to separate the silver nanoparticles from solution .It is then dried in an oven at a temperature 40oC for 24 hours. Structure characteristics was studied , the synthetic silver powder was prepared through the use of an (XRD). Results showed the composition of silver nanoparticles is a (fcc) and a constant lattice (4.086 ± 0.006 Å) by comparing it with standard tables (JCPDS) which is found perfectly matched to file with a number 04-0783, which is due to the space group Fm3 m No. 225. Particle size of nanoparticles was calculated for samples prepared using the Scherrer equation where the average grain size of (18.84 nm - 50.23 nm) was also found using the equation Williamson - Hall and ranged from (10.11 nm - 39.60 nm). As well as the mass density, density of dislocations, texture factor and the surface area of nano-particles were calculated. In addition samples prepared with an atomic force microscope (AFM) were examined and had the average diameter of the grains between (84.32 nm - 97.35 nm), and the average height ranged between (1.54 nm - 5.02 nm).
The present study stresses two of the most significant aspects of linguistic approach: Pragmatics” and the “Speech Act Theory”, revealing its importance and the stages and levels of development through Hebrew language’s speech acts analysis including (political speech, the Holy Bible, Hebrew stories).
Chronologically, Pragmatics has always been the center of linguists’ interests due to its importance in linguistic decryptions, particularly, through “Speech Act Theory” that has been initiated and developed by the most prominent philosophers and linguistics.
The prese
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The paper presents a highly accurate power flow solution, reducing the possibility of ending at local minima, by using Real-Coded Genetic Algorithm (RCGA) with system reduction and restoration. The proposed method (RCGA) is modified to reduce the total computing time by reducing the system in size to that of the generator buses, which, for any realistic system, will be smaller in number, and the load buses are eliminated. Then solving the power flow problem for the generator buses only by real-coded GA to calculate the voltage phase angles, whereas the voltage magnitudes are specified resulted in reduced computation time for the solution. Then the system is restored by calculating the voltages of the load buses in terms
... Show MoreThe problem of reconstruction of a timewise dependent coefficient and free boundary at once in a nonlocal diffusion equation under Stefan and heat Flux as nonlocal overdetermination conditions have been considered. A Crank–Nicolson finite difference method (FDM) combined with the trapezoidal rule quadrature is used for the direct problem. While the inverse problem is reformulated as a nonlinear regularized least-square optimization problem with simple bound and solved efficiently by MATLAB subroutine lsqnonlin from the optimization toolbox. Since the problem under investigation is generally ill-posed, a small error in the input data leads to a huge error in the output, then Tikhonov’s regularization technique is app
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This research deals with the design and simulation of a solar power system consisting of a KC200GT solar panel, a closed loop boost converter and a three phase inverter by using Matlab / Simulink. The mathematical equations of the solar panel design are presented. The electrical characteristics of the panel are tested at the values of 1000 for light radiation and 25 °C for temperature environment. The Proportional Integral (PI) controller is connected as feedback with the Boost converter to obtain a stable output voltage by reducing the oscillations in the voltage to charge a battery connected to the output of the converter. Two methods (Particle Swarm Optimization (PSO) and Zeigler- Nichols) are used for tuning
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An optical spectroscopic study is reported in this article to study the correlation between the supermassive black hole (SMBH) and the star formation rate (SFR) for a sample of Seyfert galaxies type (I and II). The study focused on 45 galaxy of Seyfert 1, in addition to 45 galaxy of Seyfert 2, where these samples have been selected form different survey of Salon Digital Sky Survey (SDSS). The redshift (z) of these objects were between (0.02 – 0.26). The results of Seyfert 1 galaxies shows that there good correlation between the SMBH and the SFR depending on statistical analysis parameter named Spearman’s Rank Correlation in a factor of (ρ=0.609), as well as the Seyfert 2 galaxies results show a good correlation between the SMBH and
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Mixed Kirkuk and Sharki-Baghdad crude oils were distilled into narrow fractions. The range of these narrow fractions were 10oC, starting from IBP to 350oC. The total distillates from mixed Kirkuk and Sharki-Baghdad crude oils were 58.25 vol % and 44.65 vol %, respectively.The hydrocarbons compositions (paraffin, naphthene, aromatic) in light fractions starting from IBP to 250oC were determined by using PONA analysis method. The results show that the paraffin content decreases with increasing mid percent boiling point of the fraction, while the naphthene, and aromatic increase with the increase of mid percent boiling point of mixed Kirkuk and Sharki-Baghdad crude oils. Three groups of empirical equations were developed for the prediction
... Show MoreThe aim of the current research is to identify the level of organizational culture among the headmasters and teachers of intermediate and secondary schools in Arar city. It also aims to identify the effect of job variables, qualifications, educational stage, and years of experience on the level of organizational culture and its domains. The research sample consisted of 62 participants divided into 7 headmasters and 55 teachers. The researcher used the questionnaire of the organizational culture. The researcher used also statistical methods such as mean, standard deviation, t-test, and One way ANOVA. The results revealed that the level of organizational culture and its four domains were high, and there was no effect of the variables (teac
... Show MoreBackground: Diabetic mellitus type ? is a metabolic disorder of diverse etiological factors, characterized by hyperglycemia resulting from an absolute deficiency of insulin affected childhood and adolescent. Some of these patients seek an orthodontic care .The orthodontist who is treating these medically compromised patients should have a working knowledge of the multitude of medically complex problems. This information will support and enable for delivery of high standards of dental care in general and orthodontic care in particular. The aim of this study was to analyze serum IgG levels and salivary secretory IgA (sIgA) levels in human dentine extract (HDE) before (T0) and 6 months after (T6) orthodontic treatment and to correlate anti-HDE
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