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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
Tue Dec 22 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
قياس مخاطر الائتمان المصرفي ودورها في تحقيق الافصاح المحاسبي بالمصارف العراقية: أطار مقترح
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Bank credit  function plays an important role in realizing the targets of commercial banks , so that the credit dominate the most of assets for these banks , also the credit contribute by bigger share of operational income for these banks .Bank credit faces

high challenge that it is bank credit risks which hinder realizing goals of bank credit . the researcher discover that in spite of the international accounting standards assured that it  is necessary to disclose about risks related assets, which include bank credit, and also disclosure about fund which specified to face probable loss for this credit , but the recent disclosure about bank credit risks and its provision indicate that it faces sever defect which hinder

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Publication Date
Mon Sep 15 2025
Journal Name
مجلة الانبار للقانون والعلوم السياسية
الصراعات الدولية وانعكاساتها على الامن الانساني في منطقة الشرق الاوسط بعد عام 2003
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تعد ظاهرة الصراعات ظاهرة قديمة كقدم الوجود البشري وهذا يطبق على المستوى الدولي مما يجعل الدول الصغرى هي ساحة تصفيات كما هو الحال في سوريا مما يجعل الامن الانساني فيها معدوم

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Publication Date
Fri Nov 11 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The initiative of the Central Bank of Iraq and its impact on some banking activities provided by specialized banks
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Specialized banks provide their banking activities to their customers at interest rates that are determined according to the approved bank policy, which is almost similar to most or most banks. To satisfy the financial desires of customers and at the same time it is a source of the bank's profits, However, these banks have been introduced to new services that they provide with the funds of the Central Bank initiative launched at the beginning of (2016) to address the economic stagnation that befell the country due to the (financial security) crisis that the country faced in 2014. To put forward initiatives amounting to nearly (15) trillion dinars, which were put forward through private commercial and Islamic banks and specialized

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Publication Date
Mon Jun 04 2012
Journal Name
المؤتمر العلمي الدولي الاول
اهمية بعض القياسات الجسمية والبدنية بمستوى الانجاز الرقمي في فعاليه التجديف (الكاياك) 200م
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Publication Date
Sun Jan 03 2016
Journal Name
Journal Of Educational And Psychological Researches
إنتاج المعرفة واكتسابها لدى طلبة كليات العلوم التربوية في بعض الجامعات الأردنية الرسمية
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This research attempts to propose production and acquisition of scientific knowledge among the students of educational science faculties in some universities Governmental Jordanian (Yarmouk, Jordan, Muta). In addition to sources of educational gained in some of the Governmental Jordanian universities (Yarmouk, Jordan, Muta), and to propose the necessary socio-cultural dimensions of knowledge acquisition and production, using developmental screening method, which is represented in the study design tool (questionnaire), which consisted of 4 scales, scale: The reality of the acquisition of knowledge / reality of the production of knowledge / social dimensions of knowledge acquisition and production / cultural dimensions of knowl

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
اثر استخدام دورة التعلم في تحصیل طالبات مرحلة الرابع العام للمعلومات الفیزیائیة واستبقائھا
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This research aims to reveal the impact of applying a teaching course in
gaining and preserving information by female students comparing with the
traditional method, through testing the two following hypotheses:
1. There is no difference with statistical significance at the level of
significance (0.05) between the average grades achieved by the
experimental group of female students taught using a teaching course,
and the control group of female students taught using the traditional
method.
2. There is no difference with statistical significance at the level of
significance (0.05) between the average grades achieved by the
experimental group of female students taught using a teaching course,
and the contro

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Publication Date
Sun Mar 15 2020
Journal Name
Journal Of The College Of Education For Women
Rhetoric Effect of Ibn Al Faridh’s Poetry Counterparts: اسماء خليل ابراهيم, فرج منسي محمد
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 The Sufi poetry of Ibn Al-Faridh represents a true image of the spiritual  experience, in which he presented the bright aspects of  his experience, and his suffering in it, by formulating it in a poetic form, because the Sufi poetry is the result of an experience in which the Sufi seeks to achieve his goal of reaching the truth, and this is why Ibn Al-Faridh made his poetry a tool for expression on his own experience, the poet reflected his Sufi life in which he moved rhymes and weights.

   The poet Ibn Al-Faridh stands as a witness to his making of  Sufi poetry in the service of the purpose of who said, it is the embodiment of the Sufi journey in the stages, and the fluctuation in the places and si

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Publication Date
Sat Jun 01 2024
Journal Name
مجلة الدراسات المستدامة
المسؤولية المدنية الناشئة عن الاخلال بالالتزام بضمان سلامة الاشخاص في عقد التحاليل الطبية
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Publication Date
Mon Sep 26 2022
Journal Name
جامعة بغداد/ كلية التربية للعلوم الصرفة - ابن الهيثم
مهارات التفكير المعرفي وعلاقته باليقظة العقلية لدى طلبة أقسام الرياضيات في كليات التربية
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Publication Date
Sat Dec 29 2018
Journal Name
Journal Of Planner And Development
اثر العامل الديني في تخطيط المدينة العربية والعمارة الاسلامية مدينة النجف الاشرف أنموذجاً
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