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Effect of Laser Shock Peening on the Fatigue Behavior and Mechanical Properties of Composite Materials
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In this study, Laser Shock Peening (LSP) effect on the polymeric composite materials has been investigated experimentally. Polymeric composite materials are widely used because they are easy to fabricate and have many attractive features. Unsaturated polyester resin as a matrix was selected and Aluminum powder with micro particles as a reinforcement material was used with different volume fraction (2.5%, 5% and 7.5%). Hand lay-up process was used for preparation the composites. Fatigue test with constant amplitude with stress ratio (R =-1) was carried out before and after LSP process with two levels of energy (1Joule and 2Joule). The result showed an increase in the endurance strength of 25.448% at 7.5% volume fraction when peened is 1J laser energy. Also, the ultimate strength and Young’s modulus were increased by 6.474% and 10.588% respectively after LSP with the same laser energy.  On the other hand, composites with (2.5% and 5%) volume fraction manifested a reduction in the mechanical and fatigue strength especially when treated by 2J laser energy.

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Publication Date
Tue Jan 17 2012
Journal Name
Journal Of Electron Devices
INVESTIGATION OF OPTICAL PROPERTIES OF THE PbS/CdS THIN FILMS BY THERMAL EVAPORATION
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In this work, we have investigated optical properties of the thermally evaporation PbS/CdS thin films. The optical constant such as (refractive index n, dielectric constant εi,r and Extinction coefficient κ) of the deposition films were obtained from the analysis of the experimental recorded transmittance spectral data. The optical band gap of PbS/CdS films is calculate from (αhυ)1/2 vs. photon energy curve.

Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
The relationship between social capital and knowledge sharing and their impact on improving the educational service quality: an analytical study of the views of a sample of academic staffs in the government universities in the Kurdistan Region of Iraq
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Abstract

This study aims to find the relationships between social capital (social network, social trust, shared goals) and knowledge sharing (knowledge Donating, knowledge collecting) as independent variables and their impact on improving the quality of educational services (academic staffs quality, Quality of teaching methods and study curriculums). This research is an important, because it attempts to identify the relationship between social capital and the knowledge sharing and their effect on improving the quality of educational service for universities. The study problem was determined in several questions related to the nature of the correlation relationship - the impact between the different independent variables (

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Publication Date
Fri Dec 01 2023
Journal Name
Baghdad Science Journal
Ni2+, Pt4+, Pd2+, and Mn2+ Metal ions Complexes with Azo Derived from Quinolin-2-ol and 3-amino-N-(5-methylisoxazol-3-yl) Benzenesulfonamide: Synthesis, Characterization, Thermal Study ,and Antioxidant Activity
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Diazotization reaction between quinolin-2-ol and (2-chloro-1-(4-(N-(5-methylisoxazol-3-yl)sulfamoyl)phenyl)-2l4-diazyn-1-ium was carried out resulting in ligand-HL, this in turn reacted with the next metal ions (Ni2+, Pt4+, Pd2+, and Mn2+)  forming stable complexes with unique geometries such as (tetrahedral for both Ni2+ and Mn2+, octahedral for Pt4+ and square planer for Pd2+ ). The creation of such complexes was detected by employing spectroscopic means involving ultraviolet-visible which proved the obtained geometries, fourier transfer proved the formation of azo group and the coordination with metal ion through it. Pyrolysis (TGA &

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Publication Date
Wed May 10 2023
Journal Name
Journal Of Engineering
Irrigation Scheduling Effect on Water Requirements
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Irrigation scheduling techniques is one of the suggested solutions for water scarcity problem. The study aims to show the possibility of using practical and applicable irrigation scheduling program which was designed by Water Resources Department at the University of Baghdad by using Spreadsheet Formulas for Microsoft Excel program, version 2007, with some modification to generalize it and made it applicable to various climatic zone and different soil types, as a salvation for the shortage of irrigation water inside the irrigation projects. Irrigation projects which incidence of Tigris River basin will be taken as an applicable example. This program was based on water budgeting and programmed depending on scientific concepts which facili

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Publication Date
Sun May 28 2023
Journal Name
Journal Of Inorganic And Organometallic Polymers And Materials
Improving the Dielectric, Thermal, and Electrical Properties of Poly (Methyl Methacrylate)/Hydroxyapatite Blends by Incorporating Graphene Nanoplatelets
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In this article, the casting method was used to prepare poly(methyl methacrylate)/hydroxyapatite (PMMA/HA) nanocomposite films incorporated with different contents (0.5, 1, and 1.5 wt%) of graphene nanoplatelets (Gnp). The chemical properties and surface morphology of the PMMA/HA blend and PMMA/HA/Gnp nanocomposite were characterized using FTIR, and SEM analysis. Besides, the thermal conductivity, dielectric and electrical properties at (1–107 Hz) of the PMMA/HA blend and PMMA/HA/Gnp composites were investigated. The structural analysis showed that the synthesized composites had a low agglomerated state, with multiple wrinkles of graphene flakes in the PMMA/HA blend. The thermal conductivity was improved by more than 35-fold its value for

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Publication Date
Sat Jun 01 2013
Journal Name
Int. J. Nanoelectronics And Materials
Comparsion of the physical properties for CdS and CdS doped PVA thin films prepared by spray pyrolysis
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Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
Compare between simex and Quassi-likelihood methods in estimation of regression function in the presence of measurement error
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       In recent years, the attention of researchers has increased of semi-parametric regression models, because it is possible to integrate the parametric and non-parametric regression models in one and then form a regression model has the potential to deal with the cruse of dimensionality in non-parametric models that occurs through the increasing of explanatory variables. Involved in the analysis and then decreasing the accuracy of the estimation. As well as the privilege of this type of model with flexibility in the application field compared to the parametric models which comply with certain conditions such as knowledge of the distribution of errors or the parametric models may

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Publication Date
Wed Mar 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
The Role of the Auditor in Confirming the Integrated Reports - An Exploratory Study on a Sample of External Auditors in Iraq-
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  The aim of the research is to identify the extent of the ability to ensure the integrated reports by the auditor in verifying the credibility of these reports, and their implications for the benefit of all parties dealing with the economic unit, as well as measuring the impact of the assurance procedures followed by the auditors and their role in confirming these reports.

  The research methodology was designed after studying the previous literature related to the research variables, and then the relationship between these variables was tested, through the use of a questionnaire list. A questionnaire targeting the community of auditors in the local environment, and the results of the study wer

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Publication Date
Wed Mar 23 2022
Journal Name
Journal Of Educational And Psychological Researches
The effectiveness of a teaching program based on the McCarthy Model (4MAT) in developing creative writing skills and reflective thinking among university students
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The aim of this study was to determine the effect on using the McCarthy Model (4MAT) for developing creative writing skills and reflective thinking among undergraduate students. The quasi-experimental approach was adopted. And, in order to achieve the study objective, the educational content of Teaching Ethics (Approach 401), for the plan for the primary grades teacher preparation program  was dealt with by using a teaching program based on the McCarthy Model (4MAT) was used.

The study which was done had been based on the academic achievement test for creative writing skills, and the reflective thinking test. The validity and reliability of the study tools were also confirmed. The study was applied to a sample consisting of

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Publication Date
Mon Feb 04 2019
Journal Name
Iraqi Journal Of Physics
Effect of pyridine and pyridine with substituent on photoluminescence of nanoparticles CdS prepared by liquid –liquid interface reaction
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Liquid – liquid interface reaction is the method for
preparation nanoparticles (NP'S) which depend on the super
saturation of ions that provide by using the system that consist from
toluene and water, the first one is above the second to obtain
nanoparticles (NP's) CdS at the interface separated between these
two immiscible liquid. The structure properties were characterized by
XRD-diffraction and transmission electron microscopy.
The crystalline size estimate from X-ray diffraction pattern
using Scherer equation to be about 7nm,and by TEM analysis give us
that ananosize is about 5 nm which give a strong comparable with
Bohr radius. Photoluminescence analysis give two emission peak,
the first one around

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