The aim of this work is to perform an experimental study for the effect of forced vertical vibrations on free convection heat transfer coefficient, from flat plate made of Aluminum with dimension (300 Length*100 Width*3 thickness mm).It's heated under a constant heat flux of (250-1500 W/m2 ) upward. The flat plate was located horizontally or inclined in multiple angles at rang of (0o , 30o , 45o 60o ، 90o ). The experimental study is carried out at a range of frequency (2-16 Hz) ، the amplitude at the range of (1.63-7.16 mm), and the Rayleigh number at the rang (138.991< Ra <487.275).
The results of this study show that, the relation between the heat transfer coefficient and the amplitude of vibration is incrementally for inclination angles from (0°-60°), and reaches a maximum ratio of (13%) in the horizontal position, except at the vertical position (θ=90o ) the heat transfer coefficient decreases as the vibration response increases and the maximum decrease ratio occurs at (7.6 %)
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من أهم مسائل الطلاق التي كثر حولها الخلاف: (الحلف بالطلاق وتعليقه بشرط )، لذا عمدت في هذه الصفحات اليسيرة ان اتناول بالبحث والدّراسة مسألة تُعَدُّ من المعضلات، وهي (ما يترتّب على الحلف بالطَّلاق إذا حنث الحالف). وقد فشا وكَثُرَ في الأزمنة المتأخرة الحلف بالطَّلاق في المجتمعات المسلمة، مما دفعني للكتابة فيه ببحث وسميته :
( أحـكام الحلف با
... Show MoreThe research aims to determine the effectiveness of auditing in light of the relationship between the governance of investment policy and the cost of debt in companies listed on the Iraqi Stock Exchange. The problem of the research is to raise the question about the effect of the governance of investment policy and the cost of debt on the effectiveness of auditing and auditors. During the research, the most important of them were: the existence of an impact relationship on the effectiveness of auditing through the relationship between the governance of investment policy and the cost of debt. The companies listed in the Iraqi Stock Exchange lack an effective proposed guide or framework dealing with the governance of investment policy desp
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فان موضوع بحثنا الموسوم ( مخالفات الإمام الغزالي للمعتزلة من خلال كتاب المنخول )، هو من موضوعات علم الأصول ، لان هذا العلم له أهمية كبيرة في حياة المسلم ليتوصل به الى استنباط الأحكام من الأدلة التشريعية ، وكتاب المنخول هو من الكتب الرئيسة والمهمة في هذا العلم ، وهو لحجة الإسلام الإمام الغزالي العالم الجهبذ ، قوي الحجة ، ناصع ا
... Show MoreColonialism as a movement was very popular in Europe more than two centuries before. It aimed at controlling and exploiting several countries in Africa and Asia in addition to imposing their power and control on uninhabited islands. It received adherence and criticism as well. There also appeared activists and nations who stood against it and its practices. English novels discussed this notion greatly by pointing out the bad practices of the colonizers and how the colonized received them. This paper explores two narrative fictions that tackle the different aspects of the term. While Defoe, in Robinson Crusoe (1719), shows a colonial European figure who expresses his superiority, Wells, in “The Country of the Blind” (1904), deconstructs
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مصطلح اهل الحديث من المصطلحات التى طرأ عليها التغيير في المعنى في فترة من الزمن ، اذ تطور من مصطلح كان يستخدم لوصف من كانوا يشتغلون بعلم الحديث ، الى مصطلح فكري ضم معنى جديدا لمعناه القديم، حيث شمل وصفا لمجموعة من العلماء و اتباعهم ممن كان لهم منظور خاص للنصوص و بالاخص النصوص المتشابهة.
وكان لعلماء الحديث ، بوصفهم حملة السنة النبوية
... Show MoreThe method of powder technology has been utilized in fabrication of machinable
ceramics by the approach of glass-ceramic principles. The crystalline ceramic phases
partially dissolved by host glass while the undissolved part remain responsible for the
machinability by the usual cutting tools. Thus avoiding the unnecessary use of special
dies to cast fully melted composition and initiate recrystallization process. Two types of
machinable ceramics have been successfully prepared, the first with high silica content
and the other with high alumina content. A comparison of their properties and discussed.
