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alkej-307
Study the Effect of Different Reinforcements on the Damping Properties of the Polymer Matrix Composite
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In this research, damping properties for composite materials were evaluated using logarithmic decrement method to study the effect of reinforcements on the damping ratio of the epoxy matrix. Three stages of composites were prepared in this research. The first stage included preparing binary blends of epoxy (EP) and different weight percentages of polysulfide rubber (PSR) (0%, 2.5%, 5%, 7.5% and 10%). It was found that the weight percentage 5% of polysulfide was the best percentage, which gives the best mechanical properties for the blend matrix. The advantage of this blend matrix is that; it mediates between the brittle properties of epoxy and the flexible properties of a blend matrix with the highest percentage of PSR. The second stage included reinforcing the best blend matrix of epoxy-polysulfide (the blend matrix with the best percentage of polysulfide resulted from the previous stage), by different volume percentages of short fibers (Carbon& Glass) separately and randomly. The volume percentages of fibers were (2.5%, 5%, 7.5%, and 10%). The third stage included reinforcing the blend composites with highest percentages of carbon and glass fiber, by different weight percentages of nano-particles (Red mud& Fly ash) separately. The weight percentages of particles were (0.5%, 1%, 1.5%, and 2%). The experimental results showed that blending polysulfide rubber with epoxy increased the damping ratio. As for reinforcement materials, they decreased the damping ratio, where glass fiber composites have significantly higher damping ratio than other composites.

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Publication Date
Sat Nov 12 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The effect of government investment spending on tax revenue in Iraq from( 2008 – 2020) : Applied research in The General Authority for Taxes.
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The expenditures of the general budget, in its operational and investment divisions, are a basic factor in the economic and social growth of any country, and its impact on various economic activities such as income, employees , and the standard of living of members of society. This was based on a basic premise: Does increasing or decreasing investment expenditures have an effect on increasing or decreasing the tax proceeds, What is the level of relationship between them? and to achieve the goal of the research, an inductive and analytical method was chosen to measure the impact of the investment budget expenditures on the tax outcome quantitatively using the financial data obtained from The General Authority for Taxes, Ministry of Financ

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Publication Date
Fri Mar 31 2017
Journal Name
Al-khwarizmi Engineering Journal
Design of Nonlinear PID Neural Controller for the Speed Control of a Permanent Magnet DC Motor Model based on Optimization Algorithm
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In this paper, the speed control of the real DC motor is experimentally investigated using nonlinear PID neural network controller. As a simple and fast tuning algorithm, two optimization techniques are used; trial and error method and particle swarm optimization PSO algorithm in order to tune the nonlinear PID neural controller's parameters and to find best speed response of the DC motor. To save time in the real system, a Matlab simulation package is used to carry out these algorithms to tune and find the best values of the nonlinear PID parameters. Then these parameters are used in the designed real time nonlinear PID controller system based on LabVIEW package. Simulation and experimental results are compared with each other and showe

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Publication Date
Wed Jun 14 2023
Journal Name
Al-academy
The effectiveness of the harvesting strategy in the collection of environmental art by the Institute of Fine Arts students
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 The current research aims to: (know the effectiveness of the harvesting strategy in the achievement of the students of the Institute of Fine Arts in environmental art.
- In order to know this effectiveness, the researcher put a main zero hypothesis and derived six sub-hypotheses from it. the usual way; As the research community reached (120) male and female students of the Fine Arts Institutes for the morning study in Baghdad. As for the research sample, it was chosen by the simple random method, and the number was (75) male and female students for the year 2021-2022 AD. The researcher applied a pre-knowledge test for the four groups of research to find out the level of previous experiences of students in the subject of environmen

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Publication Date
Tue Feb 15 2022
Journal Name
International Journal Of Aquatic Science
Effect of adding different levels of dried dill (Anethum gravelens) to the diet on the productive performance of broilers
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This study was conducted at the poultry research station to the office of Agricultural Research / Ministry of Agriculture / during the period 4/1/2016 to 5/5/2016 and 336 one-day-old Ross308 chicks were used, and fed on diets provided with dried dill (Anethum gravelens) at levels 0.4, 0.6 and 0.8% for treatments D2, D3 and D4, respectively, and they were compared with the control treatment D1. Each treatment included three replicates in each replicate contain 28 birds, in order to study the effect of adding different levels of dried dill plant on the productive performance and some characteristics of the carcass for broilers. The results showed a significant increase (p<0.05) in the average body weight at 5 weeks of age for the treatments (

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Publication Date
Mon Oct 06 2014
Journal Name
Journal Of Educational And Psychological Researches
The Effect of the Problem Based Learning on EFL Learners’ Achievement
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The present study discusses the problem based learning in Iraqi classroom. This method aims to involve all learners in collaborative activities and it is learner-centered method. To fulfill the aims and verify the hypothesis which reads as follow” It is hypothesized that there is no statistically significant differences between the achievements of Experimental group and control group”. Thirty learners are selected to be the sample of present study.Mann-Whitney Test for two independent samples is used to analysis the results. The analysis shows that experimental group’s members who are taught according to problem based learning gets higher scores than the control group’s members who are taught according to traditional method. This

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Publication Date
Sun Jan 04 2015
Journal Name
Journal Of Educational And Psychological Researches
The Effect of the Problem Based Learning on EFL Learners’ Achievement
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The present study discusses the problem based learning in Iraqi classroom. This method aims to involve all learners in collaborative activities and it is learner-centered method. To fulfill the aims and verify the hypothesis which reads as follow” It is hypothesized that there is no statistically significant differences between the achievements of Experimental group and control group”. Thirty learners are selected to be the sample of present study.Mann-Whitney Test for two independent samples is used to analysis the results. The analysis shows that experimental group’s members who are taught according to problem based learning gets higher scores than the control group’s members who are taught according to traditional method. This

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
The Effect of annealing temperature on the optical properties of (Cu2S)100-x( SnS2 )x thin films
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Thin films of (Cu2S)100-x( SnS2 )x at X=[ 30,40, &50)]% with thickness (0.9±0.03)µm , had been prepared by chemical spray pyrolysis method on glass substrates at 573 K. These films were then annealed under low pressure of(10-2) mbar ,373)423&473)K for one hour . This research includes , studying the the optical properties of (Cu2S)100-x-(SnS2)x at X=[ 30,40, &50)]% .Moreover studying the effect of annealing on their optical properties , in order to fabricate films with high stability and transmittance that can be used in solar cells. The transmittance and absorbance spectra had been recorded in the wavelength range (310 - 1100) nm in order to study the optical properties . It was found that these films had direct optical band

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Publication Date
Thu Jan 15 2015
Journal Name
مجلة كلية التربية-المؤتمر العلمي التخصصي لكلية التربية
Investigation the Effect of Irradiation by Gamma-Ray on the Structural and Optical Properties of (CIGS) Films
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Publication Date
Fri Jun 01 2012
Journal Name
Advances In Materials Physics And Chemistry
The Effect of Zn Concentration on the Optical Properties of Cd10–xZnxS Films for Solar Cells Applications
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ABSTRACT:In this paper, Cd10–xZnxS (x = 0.1, 0.3, 0.5) films were deposited by using chemical spray pyrolysis technique, the molar concentration precursor solution was 0.15 M/L. Depositions were done at 350°C on cleaned glass substrates. X-ray dif- fraction technique (XRD) studies for all the prepared film; all the films are crystalline with hexagonal structure .The optical properties of the prepared films were studied using measurements from VIS-UV-IR spectrophotometer at wave- length with the range 300 - 900 nm; the average transmission of the minimum doping ratio (Zn at 0.1%) was about 55% in the VIS region, it was decrease at the increasing of Zn concentration in the CdS films, The band gap of the doped CdS films was varied as 3.7, 3

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Publication Date
Wed Jun 30 2021
Journal Name
Iraqi Geological Journal
The Effect of Weighting Materials on the Rheological Properties of Iraqi and Commercial Bentonite in Direct Emulsion
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Numerous drilling additives and materials are used continuously because they are necessary to support and give the required properties of the drilling fluid so that to ensure the stability of the borehole. This paper aspires to evaluate the rheological properties of bentonite (montmorillonite) Trefawey as an alternative to using commercial bentonite. Monitoring and evaluating of the rheological and filtration properties were prepared. This exertion aims to focus on the effect of hematite, and barite on the rheological properties of the three aforementioned bentonite types. An improvement in the rheological properties of bentonite (montmorillonite). Trefawey was observed after adding the previous heavy materials. Hematite has by some

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