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Ab–Initio large unit cell calculations of the electronic structure of Si and Ge nanocrystals
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Ab – initio restricted Hartree - Fock method within the framework of large unit cell (LUC) formalism is used to investigate the electronic structure of Si and Ge nanocrystals. The surface and core properties are investigated. A large unit cell of 8 atoms is used in the present analysis. Cohesive energy, energy gap, conduction and valence band widths are obtained from the electronic structure calculations. The results are compared with available experimental data and theoretical results of other investigators. The calculated lattice constant is found to be slightly larger than the corresponding experimental value because we use only 8 atoms and we compared the results with that of the bulk crystals, nanoclusters are expected to have stronger directional bonds that in their bulk structure. The surface states are found to be mostly non-degenerated because of the effect of surface discontinuity and the existence of oxygen atoms. Valence and conduction bands are found to be wider on the surface due to the splitting of energy levels due to the existence of oxygen atoms. The present method can be used to investigate the electronic structure of bulk, surface and nanocrystals.

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Publication Date
Fri Mar 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Stability testing of time series data for CT Large industrial establishments in Iraq
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Abstract: -
The concept of joint integration of important concepts in macroeconomic application, the idea of ​​cointegration is due to the Granger (1981), and he explained it in detail in Granger and Engle in Econometrica (1987). The introduction of the joint analysis of integration in econometrics in the mid-eighties of the last century, is one of the most important developments in the experimental method for modeling, and the advantage is simply the account and use it only needs to familiarize them selves with ordinary least squares.

Cointegration seen relations equilibrium time series in the long run, even if it contained all the sequences on t

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Publication Date
Sun Jun 06 2021
Journal Name
Materials
Strengthening of Continuous Reinforced Concrete Deep Beams with Large Openings Using CFRP Strips
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To accommodate utilities in buildings, different sizes of openings are provided in the web of reinforced concrete deep beams, which cause reductions in the beam strength and stiffness. This paper aims to investigate experimentally and numerically the effectiveness of using carbon fiber reinforced polymer (CFRP) strips, as a strengthening technique, to externally strengthen reinforced concrete continuous deep beams (RCCDBs) with large openings. The experimental work included testing three RCCDBs under five-point bending. A reference specimen was prepared without openings to explore the reductions in strength and stiffness after providing large openings. Openings were created symmetrically at the center of spans of the other specimens

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Publication Date
Thu Dec 01 2011
Journal Name
Iraqi Journal Of Physics
Particle-Hole State Density Calculations with Non-Equidistant Spacing Model: II. Pairing and Exact Treatment
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In an earlier paper, the basic analytical formula for particle-hole nuclear state densities was derived for non-Equidistant Spacing Model (non-ESM) approach. In this paper, an extension of the former equation was made to include pairing. Also a suggestion was made to derive the exact formula for the particle-hole state densities that depends exactly on Fermi energy and nuclear binding energies. The results indicated that the effects of pairing reduce the state density values, with similar dependence in the ESM system but with less strength. The results of the suggested exact formula indicated some modification from earlier non-ESM approximate treatment, on the cost of more calculation time

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Publication Date
Tue Dec 30 2014
Journal Name
International Journal Of Medicine And Pharmaceutical Sciences (ijmps)
YIELDS CALCULATIONS FOR POSITRON EMISSION TOMOGRAPHY (PET) FOR NON-STANDARD RADIONUCLIDE
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The PET scans provide images that pinpoint the anatomic location of abnormal metabolic activity within the body. A radionuclide suitable for labeling a wide range of radiopharmaceuticals for positron emission tomography imaging is used also for local therapy of tumors. Among the possible methods for cyclotron production of radionuclide used in PET. We investigate the proton irradiation to produce the standard radionuclide (15O, 11C,1 3N, 18F) and some non-standard Radionuclide (76Br,124I,60Cu,66Ga,86Y and 89Zr). The total integral yield based on the main published and approved experimental results of excitation functions were calculated.

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Publication Date
Mon Jan 01 2018
Journal Name
Aip Conference Proceedings
Fabricated and investigated the structure and super conductivity properties of Bi2Sr2Can-1CunO2n+4+δ compound
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Publication Date
Mon Oct 01 2018
Journal Name
Al–bahith Al–a'alami
Axiology of Electronic programs in updating the methodology of information and communication sciences Tropes 8.4 Case Study
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The study aims to display the scientific benefit offered by modern electronic programs for various scientific research methods, while determining the positive scientific role played by these programs in modernizing the methodologies and logic of scientific thinking, especially with the rapid development of the sciences and their curricula.
These programs link accurately with scientific results. The importance of the study is to provide practical mechanisms to highlight the scientific projection of the electronic programs in various steps of scientific research.
A case study was used for Tropes version 8.4, which analyzes written, audio and visual semantic texts and presents a set of statistical results that facilitate the difficult

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Publication Date
Sat Nov 30 2019
Journal Name
Journal Of Engineering And Applied Sciences
The use of Resource Consumption Accounting and Balanced Scorecard Methods as an Integrated Framework in Correcting the Economic Unit Performance: Applied Study
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Publication Date
Fri Dec 30 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Well Performance Following Matrix Acidizing Treatment: Case Study of the Mi4 Unit in Ahdeb Oil Field
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The productivity of oil wells may be improved by determining the value of enhancing well productivity and the likely reasons or sources of formation damage after the well has been recognized as underperforming. Oil well productivity may be improved, but the economics of this gradual improvement may be compromised. It is important to analyze the influence of the skin effect on the recovery of the reserve.    The acid treatment evaluated for the well AD-12, primarily for the zone Mi4;  using a license of Stimpro Stimulation Software to validate the experimental work to the field scale, this software is considered the most comprehensive instrument for planning and monitoring matrix acid treatments and utilizing actual data to provide a far

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Publication Date
Fri Dec 30 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Well Performance Following Matrix Acidizing Treatment: Case Study of the Mi4 Unit in Ahdeb Oil Field
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The productivity of oil wells may be improved by determining the value of enhancing well productivity and the likely reasons or sources of formation damage after the well has been recognized as underperforming. Oil well productivity may be improved, but the economics of this gradual improvement may be compromised. It is important to analyze the influence of the skin effect on the recovery of the reserve.

   The acid treatment evaluated for the well AD-12, primarily for the zone Mi4;  using a license of Stimpro Stimulation Software to validate the experimental work to the field scale, this software is considered the most comprehensive instrument for planning and monitoring matrix acid treatments and utilizing actual data to prov

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Publication Date
Fri Sep 01 2023
Journal Name
Iraqi Journal Of Physics
Study the Electronic and Spectroscopic Characteristics of p-n Heterojunction Hybrid (Sn10O16/C24O6) via Density Functional Theory (DFT)
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The electronic characteristics, including the density of state and bond length, in addition to the spectroscopic properties such as IR spectrum and Raman scattering, as a function of the frequency of Sn10O16, C24O6, and hybrid junction (Sn10O16/C24O6) were studied. The methodology uses DFT for all electron levels with the hybrid function B3-LYP (Becke level, 3-parameters, Lee–Yang-Parr), with 6-311G (p,d)  basis set, and Stuttgart/Dresden (SDD) basis set, using Gaussian 09 theoretical calculations. The geometrical structures were calculated by Gaussian view 05 as a supplementary program. The band gap was calculated and compared to the measured valu

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