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.
Each poem has its own theme; each subject has its own specificity. The theme of sadness has an effect on the soul. Its privacy has become a condition that is affected by all those who have experienced this painful
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
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The legal text in the language of civil law, constitutional law, language of judges, and legal profession is concerned with a legal language and words that are coherently significant
يرمي الكتاب الى التعرّف على خصائص البحوث المنشورة في مجلة الأستاذ وبيان السمات والمكونات الأساسية للمجلة واعداد كشافات تراكمية متنوعة لها . وجاء الكتاب في خمسة مباحث تناول المبحث الاول الاطار العام للبحث ،وضمَّ مشكلة البحث وأهميته وأهدافه واجراءاته والدراسات السابقة ،وتناول المبحث الثاني الدراسة النظرية وضم التعريف بـكشافات الدوريات ،وبيان أهميتها والتعريف بـ كلية التربية /ابن رشد وبيان أهدافها ،ومن ثم ا
... Show MoreBohemia 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
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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 MoreGod 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.
The study aimed to identification the effect of brainstorming in linguistically grow of garten child the sample of study is composed from (48)male and female children have been distributed for two groups,one of them is experimental and another is disciplined for every per of garten and pre education,and they have been awarded in a number of variations. For measuring the subordinate variation(linguistically grow)the researcher prepared ascale for this purpose that consist of two parts:the first part the scale of linguistically grow of garten child(4-5 years)and the second part the scale of linguistically grow of pre education child (5-6 years).Consist of every one from (20)shapes of linguistically grow shapes for garten chil
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words of God the Quranic text , is genera words have many faces and connotations a ccording to references, cutures and Ages.That the Quranic text is fixed , But the connotations are moveable the scientists agreed about the miracle of the Qurantic text , But they differd of the Position of miracLe including the muatazala and Al- Ashaira who have adopted the idea of sytem and miracle of linguistic . Most of them were lingustics, grammerians and writers as: AL- Jahith, AL- Faraa Abivbeida , Ibn kutaba , AL -Rumani , AL -katabi , AL- Bakilaai , AL- Gargani and Others.
They also differed in what the words of Allaah mean . Is the Quranic text creature or updated ,it is the issue that exhausted the effort.of muslim scientists though its imbo