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.
يتناول البحث مدى المسؤولية المدنية المترتبة على وزارة الداخلية عن اعمال منتسبيها
Addressed the problem of the research is marked (experimentation in caves fee) concept and its role in experimentation deviate Display Num formal charges caves. The search came in four sections: general framework for research and identified the research problem and the need for him. With an indication of the importance of his presence. Then specify the search for the goals of (revealed the nature and role of experimentation in determining the nature of Manifesting fee documented on the walls of caves), followed by the establishment of the three search limits (objectivity, the temporal and spatial) were then determine the terms related to the title. Then provide the theoretical framework and indicators that resulted from academic theorizi
... Show More
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
The Holy Koran is the highest text in the eloquence, It is one of the
important sources of the linguistic syntactic and eloquent study; it impacts
upon these sciences Avery intense impact through advancing its verses as an
argument in the confirmation of the significance of the term
The holy Koran was and still the fountain of the linguistic studies, as
they tend towards it since the second century of the hegira. So this research is
a study of the expressive terms concerning the rain in the holly Koran, a
linguistic study; it aims to study the term concerning its linguistic and
conjugate significance and its expression concerning the rain through reality
and metaphor.
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
الفلسفة السياسية وفلاسفتها دراسة في فكر الفيلسوف ليو شتراوس
God bestowed upon the Imams of the Ahl al-Bayt (peace be upon them) knowledge and wisdom, in addition to give them virtue as long as it was not given to anyone from the worlds. knowledge have been enriched from them that cause pride.
تتراوح ضريبة الارض ما بين 10%من المحصول (الشعير ) و 40 -50 من الخراج
مارس العراقيون ومنهم سكان مدينة بغداد أنواعاً متعددة من الألعاب الرياضية الفردية منها السباحة ، الفروسية ، الساس ، الطابك ، والمصارعة بطريقتها القديمة ـ الزورخانة ـ وما تحملهُ من عادات وتقاليد وطقوس شبه دينية إضافة لما في حركتها من معاني القوة والبطولة ونجد أنَّ الذين يقبلون على مزاولتها عند انتشار بيوتاتها في بغداد فيما بعد هم من علية القوم ووجهاء مدينة بغداد ومن الذين كانوا يتمتعون بالاخلاق الدينية الفا
... Show More