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Studying the Effect of Addition Particles of Alumina (Al2O3) and Zirconia (ZrO2), on Some Mechanical Properties for Matrix Composites (Al-Si-Mg) Alloy
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This study is concerned with the effect of adding two kinds of ceramic materials on the mechanical properties of (Al-7%Si- 0.3%Mg) alloy, which are zirconia with particle size (20μm > P.S ≥ 0.1μm) and alumina with particle size (20μm > P.S ≥ 0.1μm) and adding them to the alloy with weight ratios (0.2, 0.4, 0.6, 0.8 and 1%). Stirring casting method has been used to make composite material by using vortex technique which is used to pull the particles to inside the melted metals and distributed them homogenously.

After that solution treatment was done to the samples at (520ºC) and artificial ageing at (170ºC) in different times, it has been noticed that the values of hardness is increased with the aging time of the original alloy and reached its highest value after (8hr).

Mechanical tests were done to the original alloy and the composite material at the maximum hardness value and represented by tensile, hardness, and wear tests. It was found that the hardness value is increased with increment of the amount of added particles; also the increment in the hardness of the alloy which is reinforced with alumina is more than that reinforced with zirconia.

Regarding the tensile test, results show that the strength and yield resistance of the composite material are more than that in the original alloy and these values are increased with increasing the amount of the added particles and they reached maximum values at (0.6%). Then they are decreased but these values remain at higher values than those in the original alloy. However, the ductility is decreased as compared with the original alloy and this decrement was more obvious with the increasing amount of the added particles. The increment of strength and yield resistance of the alloy reinforced by alumina was higher than that reinforced with zirconia, while the ductility of the alloy reinforced by zirconia was higher than that happened by the addition of alumina. Also zirconia and alumina addition to the original alloy decreased the wear rate, and the decrement would be more with the increased amount of adding particles. In addition the wear resistance of the alloy reinforced with alumina was larger than that reinforced with zirconia. X-rays testing proved that secondary phase (AlFeSi) appeared in both original alloy and the composite material. While heat treatment led to the appearance of phases (Mg2Al) and (Mg2Si) in original alloy. This was led to obvious improvement in the mechanical properties in addition to appearance ceramic particles in the microstructure of the composite material.

This structure somewhat homogenous has fine grains as compared with large grains in the microstructure of the original alloy. .        

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Publication Date
Thu Apr 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Towards building an educational system free of scientific corruption (Applied study in a sample of colleges of higher education in Iraq within the framework of the government program and the directions of the Supreme Council for Combating Corruption)
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Nations are developed with education and knowledge that raise the status of society in its various segments, beyond that it leads to underdevelopment and deterioration in various sectors, whether economic, health, social, etc. If we considered the general name of The ministry of Education & Scientific Studies, then the second part seems to be not functioning, since scientific research has no material allocation and remains based on the material potential of the university professor. As for the first half of the topic, the reality of the situation reveals problems related to the Holy Trinity of Education which is (Professor - Student - the scientific method) where universities suffer at the present time from this problem, and

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Publication Date
Tue Sep 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
دور الموازنة المرنة على أساس النشاط في الرقابة على التكاليف (دراسة تطبيقية في الشركة العامة للصناعات الجلدية)
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The research aims to identify the level of increase or decrease the product cost through the activity based flexible budgeting that gives us the chance to follows the cost since the product is planed to be made till it appears in the market and it also helps to fined out any problems that are expected to happen in the future and to put the costs under control, also to know much the surveying affects the perfect use for the complete resources in order to be used in the demanded way, the research is divided in to three sides ,the first is specialized for the theoretical side, the second is for the partical side, while the third side is specialized for the conclusions and recommendations.        &nbsp

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Publication Date
Thu Jun 01 2017
Journal Name
Journal Of The College Of Languages (jcl)
ההשפעה והשענוע בנאום הפוליטי של שמעון פרס עיון פרגמטי בדוגמאות נבחרות מנאומיו Effect and Persuasion in the Political Discourse of Shimon Peres A Pragmatic Study in Selected form of His Addresses
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במחקר הזה ניתחנו מספר נאומים של שמעון פרס, אנחנו התמקדנו בהשפעה והשכנוע אצל שמעון פרס ואיך הוא יכול להעביר את המסרים של נאומיו בסגנון פרגמטי כדי להגיע ללבו של הציבור.

 גם כן, התמקדנו בסגנון הפוליטי שהוא חושב כי התחום הזה צריך להיות ברור מול הציבור וגם כן מול דעת הקהל הבינלאומי מתוך השימוש במונחים בעלי השפעה ושכנוע להגיע למטרות המבוקשות.

 במלים אחרות, שמעון פרס, לעתים, מתמקד בשפה מליצית ויעמוד הרב

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Publication Date
Fri Dec 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Effect of the Quality of Accounting Information on the Efficiency of Investment Decisions
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Abstract

The entities responsible for regulating the financial market are seeking to provide high quality accounting information, to provide appropriate protection to investors, and thus encourage them and attract them to increase their investments. the research reached several conclusion, the most prominent of which comes  :-

1-The production of high quality accounting information reduces investment costs and costs of processing accounting information.

2- The production of high quality accounting information helps investors identify the best investment opportunities.

3- The results of the statistical analysis showed that there is significant

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Publication Date
Fri Mar 01 2019
Journal Name
Al-nahrain Journal Of Science
Effect of Active Galactic Nuclei (AGN) on the Photometric and Morphologic Properties of NGC 4414 and NGC 4369 Spiral Galaxies
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The purpose of this work is to clarify the effect of the Active Galactic Nucleus (AGN) on the properties of the galaxy. A photometric study of two galaxies by surface optical measurements techniques and by using'griz filters' was performed. The scientific material that used in this work was obtained from ''SLOAN DIGITAL SKY SURVEY'' (DR7), a fuzzy color, contour maps, photometric parameters, and color indices were studied by using surface photometric technique. The work was done by Ellipse task in IRAF (Image Reduction and Analysis Facility) software from the National Optical Astronomy Observatory (NOAO).

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Publication Date
Fri Jan 03 2020
Journal Name
Chalcogenide Letters
THE EFFECT OF Ag CONTENT AND HEAT TREATMENT ON STRUCTURAL AND MORPHOLOGICAL PROPERTIES OF THIN (Cu1-xAgx)2 ZnSnSe4 FILMS
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(Cu1-x,Agx)2ZnSnSe4 alloys have been fabricated with different Ag content(x=0, 0.1, and 0.2) successfully from their elements. Thin films of these alloys have been deposited on coring glass substrate at room temperature by thermal evaporation technique under vacuum of 10-5Torr with thickness of 800nm and deposition rate of 0.53 nm/sec. Later, films have been annealed in vacuum at (373, and 473)K, for one hour. The crystal structure of fabricated alloys and as deposited thin films had been examined by XRD analysis, which confirms the formation of tetragonal phase in [112] direction, and no secondary phases are founded. The shifting of main polycrystalline peak (112) to lower Bragg’s angle as compared to Cu2ZnSnSe4 angle refers to incorpora

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Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
The Effect of Physical Work Environment in The Flexibility of Industrial Operations
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he research specifies important subjects which contribute in improvement of productive performance in industrial companies through study and analysis of relationships and effect between dimensions of physical work environment and industrial operations flexibility in the leathers industries company. To reach these goals the information are collected is questionnaire prepared for this purpose as a tool to analyze the practical results and are recorded for a sample of 118 persons from employees. The research uses the statistical methods and analyzes the information by using SPSS system. The research reached to many conclusions; the important one is the weakness of the company to make in to account the physical envir

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Publication Date
Wed Sep 20 2023
Journal Name
Chalcogenide Letters
Calculation of the localized and extended energy states density for Ge60Se40-xTex alloy prepared by melting point method
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The DC electrical conductivity properties of Ge60Se40-xTex alloy with x = 0, 5, 10, 15 and 20). The samples were formed in the form of discs with the thickness of 0.25–0.30 cm and the diameter of 1.5 cm. Samples were pressed under a pressure of 6 tons per cm2 , using a ton hydraulic press. They were prepared after being pressed using a ton hydraulic press using a hydraulic press. Melting point technology use to preper the samples. Continuous electrical conductivity properties were recorded from room temperature to 475 K. Experimental data indicates that glass containing 15% Te has the highest electrical conductivity allowing maximum current through the sample compared to Lu with other samples. Therefore, it is found that the DC co

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Publication Date
Wed Jan 30 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Effect of The Tax Core Competencies in The Tax Settlement: An Empirical Study of The General Commission for Taxes
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This Study Sought to Determine The Relationship and Impact Between The Tax Core Capabilities and Tax Settlement The Study Took Place in The Tax Administration, and Based The Problem Was to Two Hypotheses As Solutions Initial Mocked Content to Explain The Relationship Between The Phenomena, and to Test The Validity of Assumptions And Due To The Fact That The General Authority for Taxes is The Body for The Advancement of The Collection Tax In Iraq Random Sample Was Selected to Represent The Population of The Study, Since The Sample Included 22 Individuals Representing 70% of The Total Community to Study, Represented by The Director General, Agents and Directors of Departments and Branch Managers Managers Working in The General Authority fo

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Publication Date
Tue Jan 01 2019
Journal Name
Biochem. Cell. Arch.
Effect of essential oil extracted from the peels of Citrus paradisi and Citrus sinensis on some fungi
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This study examined the effect of essential oils extracted from peel of Citrus paradisi and Citrus sinensis on two species of fungi: Penicillium oxalicum and Fusarium oxysporum as well as effect of two fungicides: Carbendazim and Thiophanatemethyl against above fungi. Results showed that the essential oil of Citrus paradisi inhibited the radial growth of Penicillium oxalicum and Fusarium oxysporum at concentration 4%. Nevertheless, the essential oil of Citrus sinensis inhibited the radial growth at concentration 5 and 4%, respectively. Furthermore, the two studied fungicides inhibited radial growth of these fungi too. Therefore, there are a positive relationship between the evaluating of concentration and the percentage of inhibiting of rad

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