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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 13 2019
Journal Name
Arab Science Heritage Journal
استخلاص عامل التلزن ( اللكتين ) من بكتريا لخلايا Enterococcus faecalis EM1 وتأثير العوامل البيئية المختلفة عليه ودوره في تلزن أنواع من البكتريا السالبة لملون غرام
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استخلص عامل التلزن من E. faecalis EM1 بعد تكسير الخلايا بعدة طرق واختيار الطريقة التي تعطي اعلى قيمة تلزن والترسيب بالكحول الاثيلي , واجري فحص التلزن وقياسه للمستخلص  مع انواع من البكتريا السالبة لملون غرام تضمنت     Escherichia coli  و Klebsiella  pneumoniae  و Serratia

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Publication Date
Tue Sep 28 2021
Journal Name
Journal Of The College Of Education For Women
The Degree of Knowledge and Use of Authentic Assessment Tools by Basic Elementary Teachers' According to some Variables: أمجد عزات جمعة، شريف عبد الرحمن السعودي، و سلمى علي العلوي
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Evaluation is one of the most important elements of  teaching process. The recent trends in evaluation and educational reform movements have called for using alternative evaluation, which focuses on performance evaluation. Authentic assessment is usually described as formative, in which students participate in their acquisition, in addition to the fact that students are productive and active, which is reflected in the students' achievement and skill level. The study aims to reveal the degree of knowledge and use of alternative assessment tools by primary school teachers in Gaza -Palestine. To meet the objective of the study, the researchers used the descriptive-analytical method and the questioner as a study tool. The study sample c

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Publication Date
Mon Jan 23 2023
Journal Name
Arab Science Heritage Journal
قيود الختام او حرود المتن دراسة تطبيقية بالاستناد على نماذج مختارة من المخطوطات الاسلامية من القرن(10-13هـ/ 16-19م) في المكتبة المركزية بأربيل:
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     Islamic manuscripts are considered an identity for the civilizational, cognitive and cultural development of nations and the Islamic world as a whole, and to identify this identity

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Publication Date
Mon Aug 03 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
أثر تطبيق الضريبة الانتقائية على السجائر في زيادة الحصيلة الضريبية: The effect of applying the selective tax on cigarettes on increasing the tax revenue
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The increasing rates of consumption of cigarettes harmful, to health in the world in general, and in Iraq in particular, and because of the costs borne by individuals, and the state as a result of addressing its damage, as well as Iraq's commitment, to international conventions against cigarettes, and demands of the World Health Organization, to raise prices to reduce consumption. Therefore, the tax Selectivity is one of the most important ways of regulating the consumption of this commodity on the one hand and increasing the tax revenue on the other. The research aims to shed light on the issue of selective tax on cigarettes and the impact of their application in increasing tax revenues and identify the effectiveness of the application

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Publication Date
Fri Dec 15 2023
Journal Name
Full Text Book Of Minar Congress10
مستوى الافصاح عن المعلومات المالية المتعلقة بالاستدامة على وفق معيار (IFRS-S1) وتأثير على أداء الشركة - بحث تطبيقي في عينة عن المصارف الاسلامية العراقية
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Publication Date
Wed Dec 28 2022
Journal Name
مجلة التربية الرياضية
إدارة درس التربية الرياضية لدى الطالب المطبق وفقا المهارات التدريسية من وجهة ً الهم نظر اعضاء هيأة التدريس في كلية التربية البدنية وعلوم الرياضة جامعة بغداد
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Publication Date
Thu Sep 15 2022
Journal Name
Alustath Journal For Human And Social Sciences
کاریگەری ستراتیجیەتی مێزگرد لەسەر دەستکەوتی بابەتی خوێندنەوە و ئەدەبی کوردی
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Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
دراسة حالة: Case Study
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The purpose of this research is to demonstrate the impact of deposit insurance to reduce banking risks, as banks in various countries of the world face a variety of risks that led to banking and financial crises that led to the failure and bankruptcy of many of its bank, which led to the banks to find quick and appropriate solutions to get rid of these difficulties These solutions include the use of bank deposit protection system for the many risks and sequences of crises that accompanied the Iraqi banking work of thefts, forgery, embezzlement and changing and unstable circumstances. The importance of studying the subject of research through the theoretical framework of banking risks as well as the framework of consideration In order to

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Publication Date
Mon Dec 25 2023
Journal Name
Journal Of Legal Sciences
Perjury of the constitutional oath by the President and members of the legislative authority - Comment on the decision of the Federal Supreme Court No. (9 / Federal / 2023) on 11/14/2023
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اصدرت المحكمة الاتحادية العليا قرارها بالعدد (9/اتحادية/2023) في 14/11/2023 والمتضمن الحكم بانهاء عضوية النائب ( ل.م.ح.د) وعضوية رئيس مجلس النواب (م.ر.ح) اعتباراً من تاريخ صدور الحكم في 14/11/2023 في قضية تتخلص وقائعها قيام النائب ( ل.م.ح.د) باقامة دعوى ضد رئيس مجلس النواب (اضافة لوظيفته ) حول قيام الاخير باستخدام طلب للاستقالة قدم من قبله بتاريخ 7/5/2022 اثناء الدورة النيابية الرابعه تحت الضغط والاكراه لاسباب سياسية ، ولم يتخذ رئ

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Publication Date
Thu Jul 02 2009
Journal Name
Journal Of Educational And Psychological Researches
الإدراك الحسي الحركي لدى الطلبة المتفوقين والمتأخرين دراسيا في المدارس الإعدادية (بحث مستل من رسالة ماجستير بنفس العنوان / جامعة بغداد) كلية التربية للبنات 2009 م
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مشكلة البحث   The Problem of the Research

 

          يعّد التحصيل الدراسي للطلبة عموما من أهم أركان النشاط العقلي في المجال التربوي، فلا تكاد تخلو منه أيه مدرسة، أبتداءً من المدارس الابتدائية وقد تسبقها رياض الأطفال، إلى المدرسة الإعدادية والجامعية ، وقد تمتد إلى مراحل متقدمة في العمر، فكان الطالب وما يزال هو محور العملية ال

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