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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
Sun Jan 03 2010
Journal Name
Journal Of Educational And Psychological Researches
اثر برنامج إرشادي في تنمية بعض المفاهيم التربوية المستنبطة من بعض المواقف اليومية التي يعيشها طفل الروضة
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It has became necessary helping the children to developing same of educational values which can be drawn from daily situations which the live. Especially the childhood stage is the basic building of value individual content since its establishment the societies take care of learning children and take care of them. Through their institutes which depended on, in this function. Therefore the importance of this, research is coming from the importance of this age stage and from importance and necessity of children aguirement the educational values and its development to them, and  the importance this research  coming from depending on guidance program with  new content and it is (al bum of pictures) fro

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Publication Date
Tue Dec 01 2009
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
تقويم وقياس العائد على الاستثمار في تدريب الموارد البشرية: بحث ميداني لعينة مختارة من الشركات العراقية الخاصة
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The great challenge that will face the management in the developed and developing countries at the same time as core issue is represented in the question of the labor productivity in the field of in the Training Of human which is believed that it will prevail upon the jobs of their organization for many coming decades in in next years. Farther more, it will limit the construction of the communities and the quality of this life. Therefore, the priority of the economics of those countries will be headed toward increasing this productivity and giving it tried finally to control economically and managerially. In the light of information era, every organization should become knowledgeable enterprise. And for this reason, the achievement of su

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Publication Date
Sat Mar 01 2008
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
اعتماد منهج ال Six Sigma كالية لتحسين جودة اداء السلطة الضريبية: دراسة حالة في الهيئة العامة للضرائب
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This research aims to improve the process Tax accounting by using the scientific method to such as Six Sigma DMAIC steps called in General. Authority for Tax accounting . this approach has been described Tax accounting process Fully and identify problems experienced by the measurement and analysis and identify the critical success factors to satisfy customers and adoption process redesign Tax accounting process with the possibility of obtaining a high-quality revenue to be used by the body to improve its performance . Collected data and information from interviews with officials, staff and see the details & the conduct & operations in the body, and used well as a questionnair to measure the quality & services present action b

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Publication Date
Tue Jan 01 2008
Journal Name
Alustath Journal For Human And Social Science
أثر شكل سبعة المعرفي في اكتساب المفاهيم الفيزيائية و فهم طبيعة العلم لدى طالبات الصف الرابع العام
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Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
أشهر العلماء العرب المسلمين وإسهاماتهم في علم الفلك من خلال كتاب سير أعلام النبلاء للذهبي (ت748هـ / 1348م)
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The Arabs muslim , throughout the historical ages, had many and varied contributions in various fields of science and knowledge, and in all scientific disciplines. They were preceded by scholars of other sects, so their books were translated into Arabic and they added to it many of their scientific research and writings that affected Arab and Islamic libraries, as these scientific research turned into basic references for the benefit of students of science in this field, and they did not stop at that, but built observatories, and invented They developed many astronomical devices in their time and observed the planets and stars, drew maps for them and determined their locations

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Publication Date
Mon Oct 15 2018
Journal Name
Arab Science Heritage Journal
رؤساء رؤساء النصارى في كتاب أخبار بطاركة كرسي المشرق (132- 542هـ/ 749- 1147م) دراسة تاريخية (القسم الثاني)
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The research deals with the Presidents of the Christians who called themselves (Ghaltka) in the book titled (orient chirsy patriarchs) that talked about their scientific practical biography adding to) that their completeness on the position of Ghaltka with its decrees and caliphs who were contemporaries to them ,as well as their places, deaths, cemeteries and their accomplishments In accordance with the powers granted to them and also it mentions the situation of The Abbasid caliphate with them and with the sons of their sect .

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Publication Date
Wed Dec 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
التنبؤ بالأحتياجات من أدوية الأمراض المزمنة والمحافظة على المال العام* دراسة تطبيقية في دائرة العيادات الطبية الشعبية
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Abstract                                                                                

The health section is considered to be one of the most important section in the  field of service economical and social unit because of its concern in the life of human begin and society and the  process of determining t

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Publication Date
Wed Jun 22 2022
Journal Name
Arab Science Heritage Journal
منهج القزويني "ت682هـ ـ 1283م " في دراسة النبات بكتابهِ "عجائب المخلوقات وغرائب الموجودات " أ.د. الاء نافع جاسم
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    he is one of the most prominent Arab personalities who contributed in the Arab Muslim world, scholars and historians who appeared in the seventh century AH - the thirteenth century AD, contributed to enrich the Arab scientific heritage in his distinguished book “The Wonders of Creatures and the Strangeness of Existences” because it contained what God Almighty created and the oddities on dry land and water

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Publication Date
Sun Nov 25 2018
Journal Name
Journal Of Planner And Development
أثر تباين الإمكانات السياحية في قوة الجذب المكاني للإقليم الحالة الدراسية: محافظة السليمانية ضمن إقليم كوردستان العراق
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Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
Different garlic forms: (lobster, mashed, crushed) and their effect on quality qualities And the molecular life of the fermented cucumber and flavor
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This study aimed to isolate and identifye the growth of microorganisms and
their effect on pickled cucumber and cabbage, the study also investigated the effect of
garlic (in the form of segments, chopped or crushed) on the mentioned pickled –food
features . Furthermore, a sense based comparison is made between vinegar-preserved
samples and vinegar-garlic preserved ones.
The following results have been obtained:
1- The isolation of staph. aureus alone from the samples and the study of its physical
and biochemical features.
2- The fresh garlic (segments, chopped and crushed) with concentration of 5%, 7.5%,
and 10% showed a damaging percentage of 100% to bacterial growth of staph. Aureus
after 24 hours of inc

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