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.
The Arab woman expressed the life of oppression that she suffers from in her masculine environment, as she expressed her linguistic abilities with eloquence and intelligence, as she did not neglect philosophy, wisdom,
سوسيولوجية "ثوارت" "الربيع العربي (دراسة تحليلية لفعل الثورات العربية)
اشتهرت بغداد بمساجدها ومأذنها ذات الطراز المتميز في التصميم والشكل والحجم والبناء والزخرفة. ونتيجة للاحتلال المتكرر والغزو الاجبي والكوارث الطبيعية الاخرى فان معظم ابنيتها تعرضت للتدمير والاندثار ولم يبق الا القليل منها شاهدا
هدف الدراسة معرفة التأثير السمي التراكمي للأعلاف الملوثة بالحنطة المتفحمة على أفراخ فروج اللحم .اجري هذا البحث في مختبرات الصحة الحيوانية التابعة لوزارة العلوم والتكنولوجيا استعمل 78 فرخاً لهذه التجربة قسمت إلى ستة مجاميع ربيت في أقفاص خاصة أعدت لهذا الغرض. تم تغذيتها يوميا على أعلاف ملوثة حسب برامج التغذية المتبعة , تمثلت المجموعة الأولى بمجموعة السيطرة والتي غذيت على عليقه تحوي الحنطة
The phenomenon of substitution is one of the morphological phenomena mentioned in the Qur'an, where the researcher defined this phenomenon from the morphological and linguistic points of view and mentioned examples of it by citing references and sources
اتضح لنا ما تقدم ان ما يسمى بالتنمية البشرية المستدامة لا تعدو تكون غير سياسة لتحشيد واستقطاب القوى المضادة للتقدم وتحويلها الى جيش موغل في منافعه بعد تشريكه بجرائم الامبريالية وتوظيفه ضد شعبه بإسم التنمية، وبإسم قلب لسلم الاولاويات، وتحريف تاريخ التقدم والتطور الذي لم يبني عرشه لا بتقديم الرعاية الانتاجية، الاقتصادية على الرعاية الاجتماعية، طيلة حقبة زمنية تجاوزت الاربعة قرون. ولما كان عصياً قلب ال
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The concept of poetics has different dimensions, part of which is related to the creative achievement, and part is related to the critical perspective. The task of this research
Bohemia AL-Kharab for Salah Salah Which contain 477Paper deal With History of Nathion This Novel Has a different styl from another IraQis Novels, this Novel has no conversation this is the basic reason Which hav this research .
The novel have 3 versions , the first one deal with explain the text in different ways , the second contains the realation ship between the text and the reader .
Which appear very clear in novel from up to down , whil the third one and the last explaine
The hermonologiq
The time bylose the relation in the novel.
The last thing is the conclusion which has the simple things conclude by the researcher from several readings to the novel
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... Show MoreThe oil sector in Iraq suffered from several difficulties led to the decline and reduction of oil production and the deterioration of refineries and transport pipeline status in addition to the weakness of the technology side and the prevalence of financial and administrative corruption besides the high costs of rehabilitation of the oil sector and also administrative and institutional problems still ongoing.
In spite of Iraq's possession of vast oil wealth allows him to play an important role in the international energy market، he is still under the level. The production of oil doesn'<
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This research attempts to study Monetary system status and financing in the CIB through 4 sections, starting with the methodology and ending with conclusions and recommendations.
These two topics of Monetary and financing, that falls within the mandate of the CBI, are researched / studied relying on the resources and relevant literature. This research is a simple contribution, but meantime it is an honest attempt to elevate the effective role of the CBI which is considered one of the most pioneering central banks in the region.