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First principles calculations of Al AsxP1-x ternary nanocrystal alloying composition
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III-V zinc-blende AlP, AlAs semiconductors and their alloy Aluminum Arsenide phosphide Al AsxP1-x ternary nanocrystals have been investigated using Ab- initio density functional theory (Ab-initio-DFT) at the generalized-gradient approximation (GGA) level with STO-3G basis set coupled with large unit cell method (LUC). The dimension of crystal is found around (1.56 – 2.24) nm at a function of increasing the sizes (8, 16, 54, 64) with different concentration of arsenide (x=0, 0.25, 0.5, 0.75 and 1) respectively. Gaussian 03 code program has been used throughout this study to calculate some of the physical properties such as the electronic properties energy gap, lattice constant, valence and conduction band as well as density of state. Results show that the lattice constant increases with the increasing in the arsenide concentration in the alloy. The total energy, cohesive energy, electron affinity and ionization potential as well as ionicity for these concentrations have been reported.

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Publication Date
Sun Jul 03 2016
Journal Name
Journal Of Educational And Psychological Researches
School Refusal Behavior of Primary First Class Pupils in Baghdad
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Objectives: The study aims to assess the school refusal behavior of first class pupils at primary schools and identifying the relationship between the school refusal behavior and some of socio-demographic characteristics for the pupils.

Methodology:  A descriptive-analytic study was initiated from November 1st, 2012 to April 1st, 2013. A random sample of 411 students is selected from a probability stratified sample of 17 primary schools for both sexes in 4 sectors in Baghdad Al-Rasafa and Al-Karkh districts which are selected randomly from first class of primary school. A Self administrative questionnaire (Parents' Version) which constructed by the rese

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Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Engineering
Optimized Zero and First Order Design of Micro Geodetic Networks
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Precision is one of the main elements that control the quality of a geodetic network, which defines as the measure of the network efficiency in propagation of random errors. This research aims to solve ZOD and FOD problems for a geodetic network using Rosenbrock Method to optimize the geodetic networks by using MATLAB programming language, to find the optimal design of geodetic network with high precision. ZOD problem was applied to a case study network consists of 19 points and 58 designed distances with a priori deviation equal to 5mm, to determine the best points in the network to consider as control points. The results showed that P55 and P73 having the minimum ellipse of error and considered as control points. FOD problem was applie

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Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
Superconducting Properties of the (Bi0.8Pb0.2)2(Sr0.9Ba0.1)2 Ca2Cu3-x Nix O10+? System.
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The effect of substitution of Ni on Cu in (Bi0.8Pb0.2)2(Sr0.9Ba0.1)2 Ca2Cu3-x Nix O10+? for (x=0,0.1….1,2,3) superconductor system and sintering time has been investigated .The samples were prepared by solid-state reaction methods. The results show that the optimum sintering temperature is equal to 850 ºC, and the sintering time is equal to 140 h. The highest transition temperature (Tc) obtained for (Bi0.8Pb0.2)2(Sr0.9Ba0.1)2 Ca2Cu3-x NixO10+? composition was 113 with x=0.8 Phase analyses of the samples by X-ray diffraction (XRD) analysis showed an orthorhombic structure with a high Tc phases (2223) as a dominant phase and low Tc phase (2212) in addition to some impurity phases.

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Publication Date
Mon Oct 30 2017
Journal Name
International Journal Of Science And Research
Measurements of X-Ray Dose Delivered at Different Depths Applied on Water Phantom
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Background: Radiotherapy, is therapy using ionizing radiation in order to deliver an optimal dose of either particulate or electromagnetic radiation to a particular area of the body with minimal damage to normal tissues. The source of radiation may be outside the body of the patient (external beam irradiation) or it may be an isotope that has been implanted or instilled into abnormal tissue or a body cavity. Called also radiotherapy. The aim of work studies the relationship between the depth dose and the high photon xray energies (6MeV and 10MeV). Patients and methods: in our work, we studied the dose distribution in water phantom given at different depths (zero-18) cm deep at1cm intervals treated with different field size (5×5-,10×1

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Publication Date
Fri Oct 22 2021
Journal Name
Iraqi Journal Of Physics
Absorption properties of novolac-alumina-graphite mixture microwave absorbers in x-band frequencies
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Absorption properties (Attenuation coefficient, the percentage of the reflection, and the percentage of absorption) in x-band have been investigated in this paper for novolac – alumina- graphite mixture. Using novolac as the host material, the samples are prepared with alumina concentrations (5%,10%,15%,20%) and graphite concentrations (5%,10%) with thickness equal to 2.2mm .Network analyzer produced by HP-8510 was used in this work to measure the attenuation coefficient. The samples (3, 5) have good attenuation of wave with bandwidth of frequencies. The maximum of attenuation is -25dB at frequency 10.28GHZ in sample (3) which has concentrations (80%novolac,10%alumina,and 5% graphite) and -24 dB at frequency 10.56GHZ in sample (5) whic

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Publication Date
Sun Feb 03 2019
Journal Name
Iraqi Journal Of Physics
Microwave losses of nanostructure Li-Ni ferrites in X-band and Ku-band
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The molar ratio(x) of Li-Ni ferrites in the formula Li0.5-0.5xNixFe2.5-
0.5xO4 was varied in range 0.1-1.0 by hydrothermal process. The
XRD, SEM, and TEM tests were conducted to examine the samples
crystalline phase and to characterize the particles shapes and sizes.
The high purity spinel structure was obtained at med and high x
values. SEM and TEM images showed the existence of different
ferrite particles shapes like nanospheres and nanorods. The
maximum particle size is around (20nm). These size encourage
occurrence of super paramagnetic state. The reflection loss and
insertion loss as microwave losses of Li-Ni ferrite-epoxy composite
of 1mm thickness and mixing ratio 39.4 wt was investigated. The
mini

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Publication Date
Mon Jun 01 2020
Journal Name
Iraqi Journal Of Physics
Synthesis and Characterization of (CdO)_1-x Mg_x films by pulsed laser deposition
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In this study, the effect of grafting with magnesium (Mg) ratios (0.1, 0.3, 0.5) on the structural and optical properties of cadmium oxide films (CdO) was studied, as these films were prepared on glass bases using the method of pulse laser deposition (PLD). The crystallization nature of the prepared membranes was examined by X-ray diffraction technique (XRD), which showed that the synthesis of the prepared membranes is polycrystalline, and (AFM) images also showed that the increased deformation with magnesium led to an increase in the grain size ratio and a decrease in surface roughness, as well as the absorption coefficient was calculated. And the optical energy gap for the prepared membranes, where it was found that the absorption coef

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Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Physics
A study of the structural and electrical properties of Ni1-x Cox Fe2O4 ferrites
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Ferrite with general formula Ni1-x Cox Fe2O4(where x=0.0.1,0.3,0.5,0.7, and 0.9), were prepared by standard ceramic technique. The main cubic spinel structure phase for all samples was confirmed by x-ray diffraction patterns. The lattice parameter results were (8.256-8.299 °A). Generally, x -ray density increased with the addition of Cobalt and showed value between (5.452-5.538gm/cm3). Atomic Force Microscopy (AFM) showed that the average grain size and surface roughness was decreasing with the increasing cobalt concentration. Scanning Electron Microscopy images show that grains had an irregular distribution and irregular shape. The A.C conductivity was found to increase with the frequency and the addition of Cobal

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Publication Date
Thu Sep 01 2022
Journal Name
Iraqi Journal Of Physics
X-Ray Emission Spectroscopy Analysis for Near-Asteroid Belt of Atmospheric of the Comets
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         According to Chandra Survey Observatory Near-Asteroid Belt Comets, the solar wind's contact with the comet produces a variety of spectral characteristics. The study of X-ray spectra produced by charge exchange is presented here. The spectrum of a comet can reveal a lot about its composition. This study has concentrated on the elemental abundance in six different comets, including 17P/Holmes, C/1999T1, C/2013A1, 9p/Temple1, and 103p/Hartley2 (NEAT). Numerous aspects of the comet's dynamics allow it to behave in a unique manner as it gets closer to the Near-Asteroid Belt. These characteristics are being examined, and some studies are still ongoing. The computations allow us to observe, for instance, how the composition of

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Publication Date
Mon Apr 01 2024
Journal Name
Journal Of Environmental Chemical Engineering
A critical review describes wastewater photocatalytic detoxification over Bi5O7I-based heterojunction photocatalysts: Characterizations, mechanism insight, and DFT calculations
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