In this paper thermo-hydrodynamic characteristics were investigated experimentally for a new type shell-helical coiled tube heat exchanger used as a storage tank of closed loop solar water heater system. Triple concentric helical coils were made of copper tubes of (12.5mm OD and 10mm ID) with coils diameter of (207, 152.2, 97mm) for outer, middle and inner coils respectively. The experiments were carried out during a clear sky days of (March and April 2012). The parameters studied in this work are: history of average temperature of shell side of the storage tank, collector heat gain, heat rejected from coils to shell side of the storage tank, collector efficiency, thermal effectiveness of the heat exchanger (storage tank), and pressure d

In this paper, a theoretical analysis of optimum bed thickness operates under mass transfer control for realizing a high efficiency and reaction conversion of an electrochemical reactor has been made based on flowthrough porous electrode (FTPE) configuration. Many models have been used to represent the optimum bed thickness by taking a look into previous works concerned and collecting all related information, data, and models. The parameters that affect the optimum bed thickness have been visualized and reviewed, and almost all of them have been examined by experimental data from different sources and based on the various models. It has been found that the increase in electrolyte flow rate, concentration, limiting current density, and sp

The aerodynamic characteristics of general three-dimensional rectangular wings are considered using non-linear interaction between two-dimensional viscous-inviscid panel method and vortex ring method. The potential flow of a two-dimensional airfoil by the pioneering Hess & Smith method was used with viscous laminar, transition and turbulent boundary layer to solve flow about complex configuration of airfoils including stalling effect. Viterna method was used to extend the aerodynamic characteristics of the specified airfoil to high angles of attacks. A modified vortex ring method was used to find the circulation values along span wise direction of the wing and then interacted with sectional circulation obtained by Kutta-Joukowsky the

Growing interest in the subject of corporate governance after the repercussions of financial collapses of some of the leaders of American companies and European, and the consequent crisis of confidence in global financial lists of companies due to weak accounting disclosure and transparency, was quick from many countries and international organizations to adopt the concept in an attempt to improve the situation of companies and promote transparency and prevent further financial crises in the future. Based on this background, the present study aims to shed light on the concept of exercising the powers of governance that has become invitations for adoption in Iraq of great importance, given the increasing role of corporations both restrict

Research questions  start from the fact that what the Arab origins of education  indicted . First question are :

- To what extent the subject of assets acquired a specific meaning in the Arabic books and educational subjects ? Is these selections are reflected on the classification of assets and their types ?
- What’s the nature of the content ? .Is there a consistency between the meaning and content ?

- What entrances handling and curriculum approach and tactics are in those books ?

- Is the assets subject introduced within  the grade  best suited ?

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تهدف الدراسة الحالية الى استعمال الانموذج اللوجستي ثنائي المعلم في تدريج مقياس الشخصية الافتراضية المتعدد الابعاد لطلبة الجامعة وفقا لنظرية الاستجابة للفقرة، والخروج بتعميم لنتائج البحث والوقوف على الاجراءات العلمية المناسبة وتوفير تطبيق عملي علمي صحيح لاعتمادها من قبل الباحثين. وقد اتبعث الباحثة الاسلوب العلمي من خطوات واجراءات في عملية بناء المقياس حيث حدت ابعاد الشخصية الافتراضية المتمثلة بسبع ابعا

ان دراسة الدين العام في اقتصاد ريعي شديد الارتباط بسوق خارجية شديدة التقلب يعد من الدراسات الحساسة كونها تضع امام الباحثين القيود المالية التي سيتكبل بها اقتصاد ضعيف قليل التنوع يعتمد على سوق الطاقة مما يفقد حالة الاستدامة المالية وتفقد الدولة القدرة على الوفاء بالتزاماتها المالية ، ان الحدود الامنة للدين العام يجب ان تكون بنسبة لا تتجاوز 60% من الناتج المحلي الاجمالي حسب اتفاقية ماسترخت الخاصة بمجلس الاتحا

In this study, the photodegradation of Congo red dye (CR) in aqueous solution was investigated using Au-Pd/TiO₂ as photocatalyst. The concentration of dye, dosage of photocatalyst, amount of H₂O₂, pH of the medium and temperature were examined to find the optimum values of these parameters. It has been found that 28 ppm was the best dye concentration. The optimum amount of photocatalyst was 0.09 g/75 mL of dye solution when the degradation percent was ~ 96 % after irradiation time of 12 hours, while the best amount of hydrogen peroxide was 7μl/75 mL of dye solution at degradation percent ~97 % after irradiation time of 10 hours, whereas pH 5 was the best value to carry out the reaction at the highest deg

تعد أساليب وطرائق تدريس المواد الدراسية العلمية من المجالات المهمة التي تساعد في تحويل المجرد إلى ثوابت في الذهن وترفع مستوى خبرات كل من المعلم والمتعلم على حد سواء إضافة إلى إنها جزء لا يتجزأ من العملية التربوية ومن الركائز المهمة التي تقوم عليها المناهج الدراسية لأنها تساعد الطلبة على اكتساب مهارات ومعلومات وتكوين اتجاهات وميول تخدم أهداف تدريس المادة وبما أن مادة الكيمياء الكمية هي إحدى المواد الدراسية

   يهدف هذا البحث إلى تأصيل الإستدلال بالقاعدة العقائدية، وبيان ضوابطه، وإبراز نماذج من أهم تطبيقاته المعاصرة، وقد أعتمد مناهج من أهمها المنهج الإستقرائي والمنهج المقارن ، وتناول البحث التعريف لقصص النبوة فى الأديان السماوية ، وعرض بعض الدراسات السابقة التى تناولت نفس الموضوع ، ثم تطرق البحث لذكر نماذج من قصص الأنبياء من الديانات السماوية الثلاث ، وتوصل البحث الى أن الأديان السماوية رغم بعض الإختلاف