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alkej-389
Transient Behavior Analysis for Solar Energy Storage in PCM-CFM Material Using Equivalent Heat Capacity Method as Storage Model
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A paraffin wax and copper foam matrix were used as a thermal energy storage material in the double passes air solar chimney (SC) collector to get ventilation effect through daytime and after sunset. Air SC collector was installed in the south wall of an insulated test room and tested with different working angles (30o, 45o and 60o). Different SC types were used; single pass, double passes flat plate collector and double pass thermal energy storage box collector (TESB). A computational model based on the finite volume method for transient tw dimensional domains was carried out to describe the heat transfer and storage in the thermal energy storage material of collector. Also, equivalent specific heat method was employed to describe the heat storage and release in the mushy zone. Experimental results referred to an increase in thermal conductivity of paraffin wax that supported by copper foam matrix more than ten times. While the ventilation effect was still active for hours after the sun set, depending on the heat storage amount. Maximum ventilation mass flow rate with TESB collector was recorded with value equals to 36.651 kg/hr., when the overall discharge coefficient that was calculated for the system equals to 0.371. Experimental results showed that the best working angle range was 45~60o, and the highest air to the collector approaching temperature appeared to the double passes flat plate collector. Results gave greater heat storage efficiency of (47)% when the maximum solar radiation was 780 W/m2 at 12.00pm, while the energy summation through duration charge time was 18460 kJ. Computational results, depending on the equivalent heat capacity method for heat storage or release from phase change material that supported by copper foam matrix, showed the behavior of paraffin wax melting and solidification situation through periodic for charge and released heat from the solar collector. Also, these results gave agreement approaching the experimental results for the heat storage in the combined heat storage material, with standard error of 16.8%.

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Publication Date
Thu Jun 01 2006
Journal Name
Journal Of The College Of Languages (jcl)
PABLO NERUDA "Premio Nobel" Y SUS ETAPAS LITERARIAS 1904_1973
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Si Alfonso x el sabio y la Escuela de Traductores de Toledo habia hecho del castellana una lengua apta para la expresión cientifica, fue Pablo Neruda quien aplicó su sentido artistico para crear una poesia amorosa de caracter lileraria. Por lo tanto, pocos poetas han llegado ton populares come. Pablo Neruda, en el mismg tiempo: se comsidera esccitor de una abundante producción literaria ne sólo en su ciudad natal de (Chile), Sino ha sida uno de los padres de la poesia hispanoamericana contemporónea. Ademas la influencia que ejerció en el grupo de poetas de la Generación del 27, con los que empezó a relacionarse durante su estancia en Madrid, fue decisiva también para la poesia espańola. Esa era la razon principal que me hizo pe

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Publication Date
Sun Jan 01 2012
Journal Name
Political Sciences Journal
دور الحكومات في بناء الدولة ضمن اطار الدستور
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دور الحكومات في بناء الدولة ضمن اطار الدستور

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Publication Date
Sun Nov 04 2018
Journal Name
Arab Science Heritage Journal
المحاريب المحاريب العراقية ، تاريخها ، انواعها في العصر العباسي
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The mihrab is an architectural element created by the Muslims for the necessities of which the direction of Qibla is set in the mosques, and the front stands in it during the prayer so as to provide a complete description of the Muslims inside the chapel. The mihrab has a third benefit in amplifying the voice during the time of prayer, Peace be upon him) and the Mosque of Damascus, the Mosque of Kairouan, and the Mosque of Amr Balfstat?.

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Publication Date
Sun Jan 02 2005
Journal Name
Political Sciences Journal
واقع ومستقبل الصراعات الدولية والاقليمية في البحر الاحمر
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واقع ومستقبل الصراعات الدولية والاقليمية في البحر الاحمر

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Publication Date
Wed Jan 02 2008
Journal Name
Political Sciences Journal
اثر المحددات الخارجية والداخلية في بناء االدولة لعراقية
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اثر المحددات الخارجية والداخلية في بناء الدولة العراقية

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Publication Date
Fri Jun 01 2012
Journal Name
Journal Of The College Of Languages (jcl)
L’ Histoire dans Les séquestrés d’Altona de Jean-Paul Sartre
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Jean-Paul Sartre est la figure principale de l’existentialisme au XXe siècle et spécialement à partir des années cinquante. En partant du travail dans les lycées dans les années trente comme professeur de philosophie, passant par la guerre qui l’obligeait à rester comme témoin passif jusqu’à de l’après guerre avec la naissance de l’existentialisme, Sartre déploie tous ses efforts pour une référence intellectuelle majeure sur tous les fronts: littéraire, philosophique et politique. Dans tous ses livres Sartre aborde le statut de la littérature des idées et de l’écrivain dans la société. Il apparait comme un réactionnaire qui cherche à « régler ses comptes avec le milieu bourgeois dans leq

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Publication Date
Tue Jan 02 2018
Journal Name
Journal Of Educational And Psychological Researches
The effect of recent technology on university students’ skills
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The study aims to identify the students’ attitudes toward recent techniques’ use in teaching; using power point software and data show to facilitate teaching approaches as well as following the approach of lecture in giving subjects, do these techniques facilitate, increase, and tackle the difficulties of subjects, do these attitudes positive or negative?, and to what extent these techniques raise up students’ motivation.   

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Publication Date
Tue May 16 2023
Journal Name
Political Sciences Journal
The Impact of the Internationalization of the Libyan Crisis on the Future of the Political Settlement
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The internationalization of the Libyan crisis and its accompanying militarization of the conflict have played a vital role in hindering to reach a comprehensive political settlement solution in Libya. The increasing international greediness in the Libyan energy resources and the geopolitical importance of the Libyan State led to the involvement of many international and regional powers in this crisis and transformed the Libyan crisis into “proxy war”.  Moreover, the Turkish direct military intervention in the Libyan crisis is considered as one of the main constraints facing the international and regional efforts to settle the Libyan crisis as a result of the Turkish insistence on its military existence in Libya to preserve i

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Publication Date
Tue Oct 05 2021
Journal Name
Arab Science Heritage Journal
العلاقةُ بينَ النّفيِ والتّوكيدِ في الصّناعةِ النّحويّةِ والمعنى
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    If the syntactic structure is a reflection of what is in the mind of the creator of synergies

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Publication Date
Thu Dec 27 2018
Journal Name
Arab Science Heritage Journal
جهود علماء مملكة غرناطة الاندلسية في الشعر التعليمي
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  نالت الحياة الادبية في مملكة غرناطة الاندلسية حظاً كبيراً 

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