The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 59o, consequently. A significant difference between the instantaneous thermal efficiency of 3.86× CPC (θc=20o) and 2.32× CPC (θc=26o), and between that for 3.61× CPC (θc=26o) and 2.32× CPC (θc=26o). It's noticed that the difference between the instantaneous thermal efficiency of 2.32× CPC (θc=59o) and 2.32× CPC (θc=26o) is small compared with the difference of the first and second cases, the instantaneous thermal efficiency of 2.32× CPC (26o) was higher than those for other three CPCs. The experimental results show that the maximum thermal efficiency of the full 2.32×CPC (26o) is 0.708, the maximum thermal efficiency of the 3.93×CPC (15o), when it's truncated to 3.84× CPC (20o), 3.61× CPC (26o) and 2.32× CPC (59o) are 0.51, 0.52 and 0.66, respectively. As the concentration ratio decreases from (3.93× to 1×), the thermal efficiency, energy losses and optical efficiency increase from (0.47 to 63), (1.58 to 7.2 K.m2/W) and (0.494 to 0.797), respectively.
It was a women's importance in ancient societies، especially Mesopotamia as they worship mother goddess first entrance religious belief، which is undoubtedly a reflection of the vision of the community it represents the natural fertility cycle and Ishtar but realistic image of women dual and contradictory and nature of the code it by a thin love compassionate and another treachery and betrayal side and hatred. As we have seen in the Epic of Gilgamesh
The research is to use the specifications and detection of the main and secondary causes of the problems that lead to the weakness and low quality of local production in Iraqi companies and develop appropriate solutions to them, as Iraqi companies suffer from the low quality of production, And the adoption of the requirements of ISO 9001: 2008, which contributes to the development of production processes within the company, and through the field co-operation and survey conducted for public companies affiliated to the Ministry of Industry and Minerals, The importance of the research through the statement of the most important problems facing the General Company for vegetable oil industry in terms of low and weak in production qual
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عرف العرب ، منذ القدم ، الأحجار الكريمة وعنوا بإقتناء أنواعا عديدة منها ، حيث كانت من أهم واردات سكان بلاد وادي الرافدين من السومريين والبابليين ثم الآشوريين ، كما عرفها المصريون القدماء وغيرهم من الشعوب القديمة ، فوجدت في قبورهم ومدافنهم وخزائن كنوزهم، مثل الياقوت الأحمر واللازورد واللؤلؤ . بالإضافة إلى ذلك فقد كان معدني الذهب والفضة من المعادن الوفيرة في هذه البلاد ، ولها الأولوية في صناعة الحلي.
The research seeks to determine the nature of audit services, their characteristics and the basic concepts of services marketing audit and definition of the rules and basic dimensions of the marketing audit services through the knowledge of the elements of the marketing mix and test the preferences of customers and auditors of the factors affecting the marketing audit services by selecting a sample of the owners of some of the projects and companies and a sample of auditors has been use the resolution to achieve the objectives of the research where a good question to the owners about the most important factors in your choice of the Audit Office and asked the organization to answer according to the standard trio (very important, a few imp
... Show Moreالغلط في القانون الانجليزي على انواع ثلاثة (غلط مشترك Common mistake ) يقع فيه الطرفان مع علم كل منهما بنية الآخر ويقبلها دون ان يشوب الاتفاق نقص او يعتريه تحفظ ، و(غلط من الجانبين Mutual mistake) يكون كل متعاقد واقعا في غلط فيما يتعلق بما قصده الآخر، فيقدم كل منهما عرضاً مخالفاً للآخر و(غلط من جانب واحدUnliteral mistake ) يقع فيه احد المتعاقدين فقط ويكون المتعاقد الآخر اما عالماً بالغلط او يفترض انه عالم به . فإذا دفع احد المتعاقدين
... Show MoreThe calamities, calamities, problems and constant dilemmas that society is experiencing have made it the responsibility of professors and researchers to find appropriate and effective solutions to these issues, and among those calamities that our societies faced was the problem of the epidemic represented by (Corona-Covid-19)
أظهرت نتائج تقدير التركيب الكيميائي لمعزول بروتين بقول العدس المنبت التي تم الحصول عليها من الأسواق المحلية في محافظة بغداد وذلك باستخدام الاستخلاص القلوي عند الرقم الهيدروجيني 9.5 PH ثم الترسيب عند نقطة التعادل الكهربائي 4.5 PH،كانت نسبة البروتين، الرطوبة، الرماد، الألياف، الدهن والكربوهيدرات (71.58، 6.44، 2.58، 1.09، 0.25، 8.66) % على التوالي، وبينت نتائج تقدير المعادن في المعزول البروتيني لكل من الكالسيوم والفسفور والحد
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