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alkej-351
Iraqi Bauxite and Porcalinite Rocks Based Refractory, Preparation and Studying Properties
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Abstract 

Locally natural occurring Iraqi rocks of Bauxite and Porcelanite (after pre calcinations at 1000oC for 1hr) were used, with the addition of different proportions of MgO and Al2O3, to prepare refractory materials. The effects of these additives on the physical and thermal properties of the prepared refractories were investigated.

Many batches of Bauxite/MgO, Bauxite/Al2O3, Bauxite/MgO/Al2O3, and   Porcelanite/ MgO/Al2O3 were prepared. The mixture is milled and classified into different size fractions; fine (less than 45μm) 40%, middle (45-75μm) 40%, and coarse (75-106μm) 20% .                         

X-ray diffraction technique was used to identify the structure of Bauxite and Porcelanite rocks. The samples were formed by semi dry pressing with the addition of few drops of water as a binder. These samples were sintered at 1100oC for 2hrs. Physical properties (linear shrinkage, density and porosity), and the thermal properties (thermal conductivity, diffusivity and specific heat) were measured for all the prepared samples.         

The results show the increasing of density is susceptible to the thermal properties, and also the addition of Al2O3 and MgO to the natural rocks have a limited effect, and the values of the parameters above  for the natural rocks, were in the levels to be used as a refractory material for lining a metal fusion furnaces and other applications.

Keywords: Bauxite, Refractory brick, Porcelanite Stone, Physical properties, Thermal properties.

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Publication Date
Sat Oct 20 2018
Journal Name
Journal Of Economics And Administrative Sciences
Evaluation of the Quality of Health Services from Patients’ Perspective: A Comparative Study between Public and Private Hospitals
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ASTRACT

The current study aimed to identify the quality of health services provided by the Omani health sector through the comparison between public and private hospitals in Dhofar Governorate, Oman. A questionnaire has been developed to collect data from 360 patients who received health services in one public Hospital (Sultan Qaboos) and three private Hospitals (Badr Al-Sama, Lifeline, and Al-Hakeeim). The data were analyzed using independent samples T-Test and One Way ANOVA. The results of the study showed that the quality levels of health services offered in private hospitals were better than public hospitals. The study results also reveled that there are significant differences between public hospitals and private hos

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Publication Date
Tue Feb 05 2019
Journal Name
Journal Of The College Of Education For Women
The difficulties in memorizing literary texts with fourth grade students from teachers’ point of view of and students
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The current research seeks to know the difficulties in memorizing literary texts with fourth grade students from teachers’ point of view of and students
The research contains a community of (10,870) students from schools affiliated to the Directorate of Karkh, second and the number of schools for boys and girls (79) School and the number of teachers (349) who are specialized in teaching Arabic language to fourth grade preparatory students and there was a section of a randomly sample of each of the students, teachers and schools .
Some actions which can be listed below:-The survey which was done by the researcher for the views of the two samples from teachers and students as the number of teachers covered in this research (20) and

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Publication Date
Mon Sep 01 2008
Journal Name
Al-khwarizmi Engineering Journal
Design and Simulation of GaussianFSK Transmitter in UHF Band Using Direct Modulation of ΣΔ Modulator Fractional-N Synthesizer
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This research involves design and simulation of GaussianFSK transmitter in UHF band using direct modulation of ΣΔ  fractional-N synthesizer with the following specifications:

Frequency range (869.9– 900.4) MHz, data rate 150kbps, channel spacing (500 kHz), Switching time 1 µs, & phase noise @10 kHz = -85dBc.

New circuit techniques have been sought to allow increased integration of radio transmitters and receivers, along with new radio architectures that take advantage of such techniques. Characteristics such as low power operation, small size, and low cost have become the dominant design criteria by which these systems are judged.

A direct modulation by ΣΔ  fractional-N synthesizer is proposed

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Publication Date
Wed Mar 30 2016
Journal Name
College Of Islamic Sciences
Ibn Al Anbari grammatical inferences On   Abu Hatim al-Sijistani through his book Clarify the stay and start
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Ibn al-Anbari, however, turned to Abu Hatim al-Sijistani in eleven places of his book ((clarify the endowment and start)). The study showed that the right and right was with the son of Anbari and that what went to Sistani saying uniqueness, and contrary to the vast majority of scientists. The study also showed that the science of grammar affects the endowment and initiation, as the study showed that the science of endowment and initiation is one of the important sciences of the Koran, which must be carefully received, researchers.

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Publication Date
Wed Dec 14 2022
Journal Name
Journal Of The College Of Languages (jcl)
Compound Sentences modification, functions and characteristics from an educational point of view: Umformungen- Funktion- Merkmale unter didaktischen Perspektiven
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This research deals with compound sentences in the German language and how to transform them and transfer them into a main sentence, touching on their functions and characteristics. Actual to nominative, which is a unique feature of the German language, with some diverse examples taken from various sources.
This case is distinguished, like other grammatical cases
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Publication Date
Wed Jan 30 2019
Journal Name
Journal Of The College Of Education For Women
The Difficulties which Face Public Basic School Principals in Jarash Governorate in Editing Formal Letters and Correspondence and Means of Dealing With These Problems as Perceived by Them
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This study aimed at identity baying the difficulties which face public basic school
principals in jar ash governorate in editing formal letters and correspondence and means of
debating with these problems to collect data the researchers developed a question air were
established the population of the study which represents its sample consisted of 129 principals
65 males and 64 females
The results of the study revealed that the principals face difficulties in office and file
management in preparing plans and reports and writing formal letters and answering them
saved recommendations were presented among which were organizing training sessions and
workshops to train the principals on how to dead with there problems.<

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Publication Date
Tue Jun 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
The Interactive Role of Organizational Elegance between Organizational Anomaly and Planned Human Resource Behavior A survey of a sample of workers in the Ministry of Construction and Housing
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This study attempts to test the interactive role played by organizational agility in enhancing the effect of organizational anomie on the behavior of planned human resources. The study of organizational anomie has increased because of the moral and legal pressures facing the organization by the external environment within its framework. To adapt to all external developments faced by these organizations, the behavior of human resources planned reflects the ability of individuals to control their behavior in different situations and situations that face them in the work.

The problem of the research indicates that there is a clear lack of understanding of what is meant by the variables studied in the sample

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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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Publication Date
Fri Jan 01 2021
Journal Name
مجلة جامعة الامام جعفر الصادق(ع ) للدراسات القانونية
حق العمل والتوظيف لذوي الاعاقة في ضوء الاتفاقيات الدولية والتشريعات العراقية
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يُعدّ الأشخاص ذوو الإعاقة أكبر أقلية في العالم وأكثرها حرمانًا، حيث تشير الإحصاءات إلى أن نحو مليار شخص، أي ما يعادل 15% من سكان العالم، يعانون من بعض أشكال الإعاقة، مع تزايد معدلاتها في البلدان النامية. وتشير الدراسات العلمية إلى أن ذوي الإعاقة قادرون على مزاولة العمل بإتقان ومثابرة، بل وقد تتفوق مهاراتهم أحيانًا على مهارات الأشخاص غير المعاقين، إذا تم اختيار العمل المناسب لقدراتهم ومواهبهم. كما أن حق العمل

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Publication Date
Fri Mar 01 2024
Journal Name
المجلة العراقية للعلوم السياسية
التغيرات المناخية واثرها على المرأة العراقية: دراسة في الاسباب وضرورات الاستجابة
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تعد التغيرات المناخية قضية بيئية عالمية وشاغلاً مشتركاً للبشرية وهي نتيجة حتمية للتطور الحضاري، لاسيما بعد قيام الثورة الصناعية، فقد كان الاستهلاك غير العقلاني لموارد الطبيعة والتوسع العمراني على حساب المساحات الخضراء آثار خطيرة على المناخ الذي يعد من اهم عناصر البيئة الطبيعية لما له من اثر واضح على كافة مجالات الحياة. على صعيد الحالة العراقية يواجه العراق تحديات عدة يفرضها تغير المناخ كارتفاع درجات الحرا

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