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Determination of the energy and kick velocity of Crab Nebula pulsar from the distribution morphology of the remnant
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The Plerion nebula is characterized by its pulsar that fills the center of the supernova remnant with radio and X-ray frequencies. In our galaxy there are nine naked plerionic systems known, of which the Crab Nebula is the best-known example. It has been studied this instance in order to investigate how the pulsar energy affect on the distribution and evolution of the remnant as well as study the pulsar kick velocity and its influence on the remnant. From the obtained results it's found that, the pulsar of the Crab Nebula injects about (2−3)𝑥 1047 erg of energy to the remnant, although this energy is small compared to the supernova explosion energy which is about 1051 erg but still plays a significant role in the distribution and the morphology as well as the dynamical expansion of the remnant. However, most of this energy is concentrate in the direction of the pulsar rotational dipole axis which makes the remnant expanding in this direction further than other regions and consequently has more density. Moreover, it's found that the pulsar kick velocity which is in order ≈110 km.s-1 also adds an expansion energy to the remnant in the direction of the kick (North West direction) added to its initial energy and due to this kick the pulsar will be shifts to the opposite direction of the kick the South East direction, which cause the pulsar to leave its birth position and finally leave the remnant itself.

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Publication Date
Thu Mar 31 2022
Journal Name
Journal Of The College Of Education For Women
The Reality of Evaluating Teacher Performance in the Sultanate of Oman in Light of Global Models
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The aim of the research is to reveal the reality of teacher performance evaluation in the Sultanate of Oman in light of some global models. The study followed a qualitative descriptive research design. Seven forms of teacher formative and summative assessments were analyzed. Besides, an analytical template was developed, consisting of six areas related to the teaching performance of teachers. These included: lesson planning and preparation, learning environment, education, professional development, student academic, and community and parental partnership. The study reached a number of results; the most notable is the lack of change of forms for more than a decade despite the rapid development of the educational system in the sultanate in

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Publication Date
Wed Mar 01 2023
Journal Name
Al-khwarizmi Engineering Journal
Study of the Effect of Magnetic Abrasive Finishing on the Material Removal of AA1100 Aluminum Alloy
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This study evaluates the performance of magnetic abrasive finishing (MAF) of aluminum alloy in terms of achieving materials removal (MR). A vertical milling machine is used to perform the finishing process using a developed MAF unit that consists of an inductor made out of a 150 mm long and 20 mm diameter iron core wound with 1500 turns and 0.5 mm copper wire. The commutator and magnetic pole are attached at the top and bottom of the inductor, respectively. The required current is supplied using a DC power supply. The South Pole workpiece is a 100×50×3 mm3 plate of AA 1100 aluminum alloy, whereas the magnetic pole represented the North Pole. Pole rotational speed, applied current, and abrasive finishing time was selected as

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Publication Date
Sat Jun 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
A field study of the problems of queues at some checkpoints in the city of Baghdad
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Abstract

Due to the momentum of winning in the streets of the city of Baghdad as a result of the large number of checkpoints so felt researcher to conduct a field visit to find out the main reasons that led to this congestion and to find practical solutions to mitigate wastage winning the arrival time citizen to where you want the least possible time.

This research aims to overcome the difficulties experienced by citizens to reach their places of work and reduce waste at the time of service and waiting time as well as reduce the cost of waiting.

Has emerged study a set of conclusions, including the use of model queue (G / G / C) and the mome

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Publication Date
Fri Nov 01 2013
Journal Name
International Journal Of Advanced Research
The effects of alkaloid extracted of Solanum nigrum leaves on the biological performance of Dialerodus citri
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Publication Date
Mon May 01 2023
Journal Name
Materials Today: Proceedings
An experimental study of the effects of matrix acidising on the petrophysical characteristics of carbonate formation
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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
The role of some types of erythrocytes on the growth of Entamoeba histolytica trophozoite in vitro
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The parasite E.histolytica was first isolated from a stool sample, and then cultivated and maintained in vitro using Locke-egg medium (LEM) and Liver infusion agar medium (LIAM) . Then, the effect of some types of erythrocytes (human and sheep), on the growth and activity of the parasite in the two culture media was investigated. The parasite was able to ingest and lysis erythrocytes of human and sheep that were supplemented to the culture media and such manipulation was able to augment the reproduction rate of the cultivated E. histolytica, however, such consequence was media- and concentration-dependent. The reproduction rate was significantly increased (66.0, 57.5 and 58.6%, respectively) in LEM medium containing human erythrocytes ty

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Publication Date
Tue Mar 30 2010
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
The Effect of Operating Conditions of Urea Dewaxing on the Pour Point of Light Lubricating Oil
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An investigation was conducted for dewaxing of lubricating oil fraction by urea to reduce the pour point.In this study mixture of 45 % methyl ethyl ketone (MEK) and 55 % toluene was used as a solvent. The studied variables are mixing time (10-70 min), solvent to oil volume ratio (0.5:1- 2:1), urea to wax weight ratio (2- 6) and constant mixing speed 1500 rpm. By analysis of the experimental results, the best operating conditions achieved are mixing time 40 min, solvent/oil 2:1 volume ratio, and urea/wax 4:1 weight ratio. At these conditions the pour point of the lubricating oil decreases from 24 ° C to -13 °C.

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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
The Influence of Alkaline Treatment of Recycled Natural Materials on the Properties of Epoxy Resin Composites
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Natural fibers and particles reinforced composites are being broadly used due to their bio and specific properties such as low density and easy to machine and production with low cost. In this work, water absorption and mechanical properties such as tensile strength, flexural strength and impact strength of recycled jute fibers reinforced epoxy resin were enhanced by treating these fibers with alkaline solution. The recycled jute fibers were treated with different concentration of (NaOH) solution at (25 0C) for a period of (24) hours. From the obtained results, it was found that all these properties are improved when fibers treated with (7.5wt% NaOH) related to untreated fibers. Conversely, the mentioned properties of composit

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Publication Date
Wed Sep 29 2021
Journal Name
College Of Islamic Sciences
The position of Al-Jassas (D. 370 AH) of the verses of "As-Sifat Al-Khbriya"
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This research aims at know the position of Al-Jassas Al- Hanafi (D. 370 AH) of  "As-Sifat Al- Khbriya", through his interpretation: (the provisions of Qur'an), by studying his interpretation of the verses related to this issue.

The most significant results of this study that Al-Jassas did not consider the words that called: "As-Sifat Al- Khbriya" as adjectives to Allah almighty, but he consider them contained an inappropriate meaning to Allah almighty, thus it must be referred to the perfect arbitrator, so he was believe in opinion of interpretation. and interpretations of Al-Jassas for the related of the Qur'an verses relat

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Publication Date
Thu Sep 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
360 degree reverse feedback / comparative analytical study for a sample of managers and heads of departments in the Central Electricity DepartmentAnd the General Directorate of Water and Sewage
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يسعى البحث إلى الاهتمام بإحدى الوظائف المهمة في إدارة الموارد البشرية وهي تقويم الأداء التي تواجه مجموعة من الانتقادات والآراء السلبية، اذ ظهر في الأّونة الأخيرة أنموذج جديد يمكن إن يتجاوز تلك السلبيات وهو أنموذج التغذية العكسية المتعدد المصادر درجة .وقد حاول الباحثان توظيف هذا المفهوم في اثنتين من المنظمات العامة العراقية هما (دائرة كهرباء الوسط) التابعة لوزارة الكهرباء
و (دائرة الماء والمجاري) ال

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