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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
Mon Mar 01 2010
Journal Name
Al-khwarizmi Engineering Journal
Synthetic Sacks as Reinforced Fibers in the Thermosetting Composites
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This study was carried out to investigate the preparation of thermosetting polymeric blend consisting of three adhesive types, namely: epoxy, polyvinyl formal (PVF) and unsaturated polyester. Both of epoxy and PVF were used as a matrix-binder at fixed weight. Whilst unsaturated polyester was used at different weights and added to the matrix so as to produce prepared epoxy-PVF-unsaturated polyester blend. Several experiments were performed at different operating conditions, mixing speed and time at room temperature to identify the most favorable operating conditions. The optimum mixing speed and mixing time for the prepared blend were 500rpm and 5 minutes respectively.

      Solid wastes-synthetic sack fib

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Publication Date
Thu Mar 31 2022
Journal Name
Journal Of The College Of Education For Women
Human Properties of Singapore’s People and their Impact on the State Might
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The research aims to study some of the human characteristics of the state of Singapore to know the impact of these characteristics on the strength of the state, its development and. The research included two aspects, theoretical and analytical, using the descriptive analytical method, force analysis method, as well as the historical method. The data was analyzed according to mathematical equations, including the size of the country's population, the extraction of the population growth rate and the concept of age structure, where some indicators related to this concept have been explained. The researcher reached a set of results, the most important of which were: that the population size of the state of Singapore in the period between (19

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Publication Date
Sat Aug 01 2020
Journal Name
Iop Conference Series: Earth And Environmental Science
Response of Celery to addition of nitrogen and spray with salicylic acid in the leaves content of nutrients
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Abstract<p>To study the response of the celery plant to nitrogen fertilization and spray with salicylic acid in the leaves content of nutrients, the research was conducted in one of the fields of the Department of Horticulture and Gardening Engineering / College of Agriculture / University of Baghdad within the 2019-2018 season. The research was carried out as a global experiment and with the design of complete randomized sectors (RCBD) and with three replicates, the first factor included the addition of nitrogen with three levels and its symbol (N) (N1 control), (N2) g / m<sup>2</sup> 18 ), (N3) 37 g / m<sup>2</sup> and the second factor spraying acid salicylic is denoted by</p> ... Show More
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Publication Date
Fri Nov 29 2019
Journal Name
Iraqi Journal Of Physics
CdSe/CdS core/shell in polyacrylamide polymer matrix for Quantumdots Luminescent solar concentrator
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Luminescent solar concentrator (LSC) are used to enhance       photoresponsivity of solar cell. The Quantumdots luminescent solar concentrator (QDLSC) consists of CdSe/CdS core/shell nanoparticles embedded in polyacrylamide polymer matrix positioned on the top surface of the silicon solar cell. This procedure improves the conversion efficiency of the bare silicon solar cell. The conversion efficiency of the solar cell has increased from 7.3% to 10.3%.  this improvement is referred to the widening of the response spectral region window  of the a- Si. Solar cell.

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Publication Date
Sun Jun 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
تحليل – الكلفة – الحجم – الربح – في ظل نظام الكلفة على أساس الأنشطة
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Recent advancement in production technologist of manufacturing processes have left an important effects upon cost structure. Moreover the problem for providing necessary and adequate information for managerial decision making.

Therefore the cost – volume – profit analysis under the new activity based costing has replace the old method for Analysing the relation between C.V.P with respect to profit planning and control.

In brief the C.V.P object is to discuss the effect of changes on profit resulting from changes in sales volume, cost of manufacturing and selling price.

This study consists of four chapters:

The first chapter dea

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Publication Date
Sat Sep 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
أثر تحليل كلف النوعية على أساس الانشطة في تحقيق الميزة التنافسية
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يتطلب تحقيق تمايز الوحدة الاقتصادية في ظل استعمال تقنيات الأعمال الحديثة وازدياد المنافسة وعالمية الأعمال ضرورة الاهتمام بمستوى نوعية المنتجات وما تتطلبه هذه النوعية من كلف والتي تسمى بكلف النوعية، إذ ان العديد من الشركات العالمية قد قامت بدراسة وتحليل هذه الكلف ووضع برامج خاصة بها بهدف تخفيضها إلى أدنى حدٍ ممكن وبما يكفل تحقيق العديد من المنافع والتوفيرات في هذه الكلف وبما يرشد عملية اتخاذ القرارات

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Publication Date
Wed Dec 01 2021
Journal Name
Journal Of Physics: Conference Series
Analytical Study of the Royal-Jelly Effect on Sperms Morphological Characteristics and some Liver Function Parameters and their Correlation with some Antioxidants in Male Albino Rats Treated with Pregabalin Drug
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Abstract<p>In recent years, the consideration of natural products as anti-inflammatory and antioxidative treatments has more interested worldwide. Moreover, natural products are easily obtained and are relatively safe the Royal jelly (RJ) is one of them. The current study was carried to evaluate the effects of pregabalin (PGB) on physiological activity of sperms, reproductive hormones assay and some biochemical analysis. Forty (40) male albino rats (10-weeks-old) were divided into four groups (10 rats each): G1 (treated with PGB drug, 150 mg/kg B.wt (Lyrica-Pfizer-Pharmaceutical Industries), G2 (treated with RJ 1g/kg), G3 (treated with PGB drug and RJ together), and G4 control treated with norma</p> ... Show More
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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Some Estimation Methods Of GM(1,1) Model With Missing Data and Practical Application
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This paper presents a grey model GM(1,1) of the first rank and a variable one and is the basis of the grey system theory , This research dealt  properties of grey model and a set of methods to estimate parameters of the grey model GM(1,1)  is the least square Method (LS) , weighted least square method (WLS), total least square method (TLS) and gradient descent method  (DS). These methods were compared based on two types of standards: Mean square error (MSE), mean absolute percentage error (MAPE), and after comparison using simulation the best method was applied to real data represented by the rate of consumption of the two types of oils a Heavy fuel (HFO) and diesel fuel (D.O) and has been applied several tests to

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Publication Date
Wed Sep 25 2019
Journal Name
Journal Of The College Of Education For Women
قال تعالى: (سنريهم ءايتنا في الافاق وفي انفسهم حتى يتبين لهم انه الحق اولم يكف بربك انه على كل شئ شهيد) -دراسة وتحليل-
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فقد تناولت في موضوعي هذه الآية الكريمة فقد جاء في هذه الآية تعليم من الله عز وجل لرسوله (ص) فلكل داع الى الله من أمته, اسلوباٌ يدعوا به الناس ومحاجة الكافرين بالقرآن, وفيها بيان من الله عز وجل بأنه سيري الناس في المستقبل بعض آياته في كونه, وهي آيات دالات على أن القران حق منزل من عند الله جل جلاله, وليس من وضع البشر, فالناس عاجز عن معرفة الآيات الباهرات التي سيريها الله عز وجل للناس في كونه , وقد أخبرهم عنها في القرآ

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Publication Date
Sat Dec 30 2023
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Strategic Cohesion on Administrative Excellence
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This research aims to test the effect of strategic cohesion with its dimensions (organizational excitement, organizational casting, organizational synergy) as an independent variable on administrative excellence as a dependent variable in the Ministry of Planning, and through surveying several employees (general managers, heads of departments,  and units managers). As a research community, and based on the importance of the research topic in the aforementioned research community. The researchers have adopted the descriptive-analytical using the questionnaire as the main data collection. 155 questionnaires were distributed, yet,114 of them were retrieved and 110 were used for final statistical analysis. The researchers used the relev

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